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Sample records for lobster homarus gammarus

  1. Genotype Reconstruction of Paternity in European Lobsters (Homarus gammarus).

    Science.gov (United States)

    Ellis, Charlie D; Hodgson, David J; André, Carl; Sørdalen, Tonje K; Knutsen, Halvor; Griffiths, Amber G F

    2015-01-01

    Decapod crustaceans exhibit considerable variation in fertilisation strategies, ranging from pervasive single paternity to the near-ubiquitous presence of multiple paternity, and such knowledge of mating systems and behaviour are required for the informed management of commercially-exploited marine fisheries. We used genetic markers to assess the paternity of individual broods in the European lobster, Homarus gammarus, a species for which paternity structure is unknown. Using 13 multiplexed microsatellite loci, three of which are newly described in this study, we genotyped 10 eggs from each of 34 females collected from an Atlantic peninsula in the south-western United Kingdom. Single reconstructed paternal genotypes explained all observed progeny genotypes in each of the 34 egg clutches, and each clutch was fertilised by a different male. Simulations indicated that the probability of detecting multiple paternity was in excess of 95% if secondary sires account for at least a quarter of the brood, and in excess of 99% where additional sire success was approximately equal. Our results show that multiple paternal fertilisations are either absent, unusual, or highly skewed in favour of a single male among H. gammarus in this area. Potential mechanisms upholding single paternal fertilisation are discussed, along with the prospective utility of parentage assignments in evaluations of hatchery stocking and other fishery conservation approaches in light of this finding.

  2. Genotype Reconstruction of Paternity in European Lobsters (Homarus gammarus.

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    Charlie D Ellis

    Full Text Available Decapod crustaceans exhibit considerable variation in fertilisation strategies, ranging from pervasive single paternity to the near-ubiquitous presence of multiple paternity, and such knowledge of mating systems and behaviour are required for the informed management of commercially-exploited marine fisheries. We used genetic markers to assess the paternity of individual broods in the European lobster, Homarus gammarus, a species for which paternity structure is unknown. Using 13 multiplexed microsatellite loci, three of which are newly described in this study, we genotyped 10 eggs from each of 34 females collected from an Atlantic peninsula in the south-western United Kingdom. Single reconstructed paternal genotypes explained all observed progeny genotypes in each of the 34 egg clutches, and each clutch was fertilised by a different male. Simulations indicated that the probability of detecting multiple paternity was in excess of 95% if secondary sires account for at least a quarter of the brood, and in excess of 99% where additional sire success was approximately equal. Our results show that multiple paternal fertilisations are either absent, unusual, or highly skewed in favour of a single male among H. gammarus in this area. Potential mechanisms upholding single paternal fertilisation are discussed, along with the prospective utility of parentage assignments in evaluations of hatchery stocking and other fishery conservation approaches in light of this finding.

  3. Aspartic cathepsin D endopeptidase contributes to extracellular digestion in clawed lobsters Homarus americanus and Homarus gammarus.

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    Rojo, Liliana; Muhlia-Almazan, Adriana; Saborowski, Reinhard; García-Carreño, Fernando

    2010-11-01

    Acid digestive proteinases were studied in the gastric fluids of two species of clawed lobster (Homarus americanus and Homarus gammarus). An active protein was identified in both species as aspartic proteinase by specific inhibition with pepstatin A. It was confirmed as cathepsin D by mass mapping, N-terminal, and full-length cDNA sequencing. Both lobster species transcribed two cathepsin D mRNAs: cathepsin D1 and cathepsin D2. Cathepsin D1 mRNA was detected only in the midgut gland, suggesting its function as a digestive enzyme. Cathepsin D2 mRNA was found in the midgut gland, gonads, and muscle. The deduced amino acid sequence of cathepsin D1 and cathepsin D2 possesses two catalytic DTG active-site motifs, the hallmark of aspartic proteinases. The putatively active cathepsin D1 has a molecular mass of 36.4 kDa and a calculated pI of 4.14 and possesses three potential glycosylation sites. The sequences showed highest similarities with cathepsin D from insects but also with another crustacean cathepsin D. Cathepsin D1 transcripts were quantified during a starvation period using real-time qPCR. In H. americanus, 15 days of starvation did not cause significant changes, but subsequent feeding caused a 2.5-fold increase. In H. gammarus, starvation caused a 40% reduction in cathepsin D1 mRNA, and no effect was observed with subsequent feeding.

  4. Are European lobsters (Homarus gammarus) susceptible to infection by a temperate Hematodinium sp.?

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    Davies, Charlotte E; Rowley, Andrew F

    2015-05-01

    Hematodinium spp. infect over 40 species of crustaceans worldwide, but have not been reported to infect the European lobster, Homarus gammarus. In this study, Hematodinium parasites (a mixture of uni- and multinucleate trophont-like stages) were taken from donor crabs (Cancer pagurus) and injected into juvenile H. gammarus. Juvenile C. pagurus were also injected with the same inoculum. Haemolymph was taken at regular intervals and examined for the presence of Hematodinium using light microscopy and PCR, in two separate experiments of duration 4 and 8months. All lobsters were negative for Hematodinium whilst the C. pagurus challenged became infected. It is concluded that European lobsters are not susceptible to infection with a clade of Hematodinium that infects C. pagurus. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Cold-adapted digestive aspartic protease of the clawed lobsters Homarus americanus and Homarus gammarus: biochemical characterization.

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    Rojo, Liliana; García-Carreño, Fernando; de Los Angeles Navarrete del Toro, Maria

    2013-02-01

    Aspartic proteinases in the gastric fluid of clawed lobsters Homarus americanus and Homarus gammarus were isolated to homogeneity by single-step pepstatin-A affinity chromatography; such enzymes have been previously identified as cathepsin D-like enzymes based on their deduced amino acid sequence. Here, we describe their biochemical characteristics; the properties of the lobster enzymes were compared with those of its homolog, bovine cathepsin D, and found to be unique in a number of ways. The lobster enzymes demonstrated hydrolytic activity against synthetic and natural substrates at a wider range of pH; they were more temperature-sensitive, showed no changes in the K(M) value at 4°C, 10°C, and 25°C, and had 20-fold higher k(cat)/K(M) values than bovine enzyme. The bovine enzyme was temperature-dependent. We propose that both properties arose from an increase in molecular flexibility required to compensate for the reduction of reaction rates at low habitat temperatures. This is supported by the fast denaturation rates induced by temperature.

  6. Male but not female olfaction is crucial for intermolt mating in European lobsters (Homarus gammarus L.).

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    Skog, Malin

    2009-02-01

    Chemical signals are common in most crustacean social interactions and are often perceived via chemosensory (olfactory) organs on the first antenna. Intermolt courtship behaviors and mating were investigated in size-matched pairs of intermolt European lobsters (Homarus gammarus) where the olfactory receptors of either the male or the female were lesioned with distilled water (olfactory ablation) or seawater (control). Matings or advanced male courtship behaviors (mounting and turning) were common in seawater controls and olfactory-ablated females. In contrast, when male olfaction was ablated with distilled water, there was not a single mating, and the only male courtship behaviors seen were a few very brief and unsuccessful mounting attempts. Individual females mated up to 5 times with different males, showing that previously inseminated females were still attractive to males. Thus, male but not female olfaction is crucial for intermolt mating in H. gammarus, indicating the presence of a female sex pheromone during the entire female molt cycle, not only at the time of molting. Female sex discrimination may be based on other cues from the male in combination with typical male behaviors.

  7. A model for the bioaccumulation of {sup 99}Tc in lobsters (Homarus gammarus) from the West Cumbrian coast

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    Olsen, Y.S.; Vives i Batlle, J. E-mail: jordi.vives@westlakes.ac.uk

    2003-07-01

    A biokinetic model is presented that simulates the uptake and release of {sup 99}Tc by the European lobster (Homarus gammarus). This organism is of significant radioecological interest since lobsters, in contrast to most other organisms, have a high affinity for {sup 99}Tc. The model is designed to represent annually averaged {sup 99}Tc concentrations in lobsters from the Cumbrian coast, where significant levels of {sup 99}Tc have been released under authorisation by the nuclear fuel reprocessing plant at BNFL Sellafield. This paper describes the construction of the model, how it was calibrated using data from published literature, and preliminary results indicating that model output agrees well with the available monitoring data. Given that this model successfully combines laboratory and field data, this research could potentially make a significant contribution to the field, as, to date, it has been difficult to predict and explain concentrations of {sup 99}Tc in lobsters.

  8. A model for the bioaccumulation of 99Tc in lobsters (Homarus gammarus) from the West Cumbrian coast

    International Nuclear Information System (INIS)

    Olsen, Y.S.; Vives i Batlle, J.

    2003-01-01

    A biokinetic model is presented that simulates the uptake and release of 99 Tc by the European lobster (Homarus gammarus). This organism is of significant radioecological interest since lobsters, in contrast to most other organisms, have a high affinity for 99 Tc. The model is designed to represent annually averaged 99 Tc concentrations in lobsters from the Cumbrian coast, where significant levels of 99 Tc have been released under authorisation by the nuclear fuel reprocessing plant at BNFL Sellafield. This paper describes the construction of the model, how it was calibrated using data from published literature, and preliminary results indicating that model output agrees well with the available monitoring data. Given that this model successfully combines laboratory and field data, this research could potentially make a significant contribution to the field, as, to date, it has been difficult to predict and explain concentrations of 99 Tc in lobsters

  9. Directional preference of European lobster (Homarus gammarus movements on the Yorkshire Coast

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    James Michael Wood

    2016-08-01

    Full Text Available Recaptures of 838 tagged Homarus gammarus individuals identified a directional preference, with bearings from release to recapture concentrated along a North-West to South-East axis, aligning with the predominant current direction for the study site.

  10. Detailed surface morphology of the 'lobster louse' copepod, Nicothoë astaci, a haematophagous gill parasite of the European lobster, Homarus gammarus.

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    Davies, Charlotte E; Thomas, Gethin R; Maffeis, Thierry G G; Wootton, Emma C; Penny, Mark W; Rowley, Andrew F

    2014-10-01

    The ectoparasitic copepod, Nicothoë astaci (the 'lobster louse'), infests the gills of the European lobster, Homarus gammarus. There have been limited studies on this haematophagous species; therefore knowledge of this parasite is rudimentary. The current study examines the surface morphology of this parasitic copepod, detached from the host, concentrating on adaptations of the suctorial mouthpart, the oral disc. Cryo-scanning electron microscopy revealed structural adaptations that facilitate attachment of these parasites to the gill filaments of their lobster host. The aperture of the feeding channel, through which host haemolymph is drawn, is only ca. 5μm in diameter. The edge of the oral disc is lined with numerous setae, whilst the surface of the disc is covered with large numbers of small (copepod host. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Effect of CO2-related acidification on aspects of the larval development of the European lobster, Homarus gammarus (L.

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    D. Boothroyd

    2009-08-01

    Full Text Available Oceanic uptake of anthropogenic CO2 results in a reduction in pH termed "Ocean Acidification" (OA. Comparatively little attention has been given to the effect of OA on the early life history stages of marine animals. Consequently, we investigated the effect of culture in CO2-acidified sea water (approx. 1200 ppm, i.e. average values predicted using IPCC 2007 A1F1 emissions scenarios for year 2100 on early larval stages of an economically important crustacean, the European lobster Homarus gammarus. Culture in CO2-acidified sea water did not significantly affect carapace length of H. gammarus. However, there was a reduction in carapace mass during the final stage of larval development in CO2-acidified sea water. This co-occurred with a reduction in exoskeletal mineral (calcium and magnesium content of the carapace. As the control and high CO2 treatments were not undersaturated with respect to any of the calcium carbonate polymorphs measured, the physiological alterations we record are most likely the result of acidosis or hypercapnia interfering with normal homeostatic function, and not a direct impact on the carbonate supply-side of calcification per se. Thus despite there being no observed effect on survival, carapace length, or zoeal progression, OA related (indirect disruption of calcification and carapace mass might still adversely affect the competitive fitness and recruitment success of larval lobsters with serious consequences for population dynamics and marine ecosystem function.

  12. Limited prevalence of gaffkaemia (Aerococcus viridans var. homari) isolated from wild-caught European lobsters Homarus gammarus in England and Wales.

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    Stebbing, P D; Pond, M J; Peeler, E; Small, H J; Greenwood, S J; Verner-Jeffreys, D

    2012-08-27

    Gaffkaemia, caused by Aerococcus viridans var. homari, causes fatal infections in Homarus spp. (clawed lobsters). Despite its high economic significance to the lobster fisheries in the USA and northern Europe, data on its prevalence in captured and wild populations, particularly in Europe, is scarce. Following an outbreak of gaffkaemia in a European lobster holding facility in South Wales (UK), a base-line survey was conducted for gaffkaemia in wild populations of European lobster Homarus gammarus around the coast of England and Wales. In addition, isolates recovered from the original outbreak and the survey were typed using pulsed-field gel electrophoresis (PFGE) and compared with previously characterised isolates from the USA, UK and Canada. Locally caught H. gammarus were sampled at 30 sites from around the coast of England and Wales between March 2006 and October 2008. Results confirmed that the prevalence of gaffkaemia in populations of H. gammarus was low, with only 9 positive isolates recovered from 952 samples examined. PFGE analysis showed that the isolates from the outbreak investigation shared the same pulsotype as A. viridans var. homari isolates from the USA, Norway and Canada, as well as an isolate (NCIMB 1119) reportedly recovered from an outbreak of European lobsters in England in the 1960s. This confirms earlier studies that suggest virulent strains of A. viridans var. homari show very limited geographical or temporal genetic variation and were introduced into the UK with American lobsters H. americanus.

  13. Effect of an insect juvenile hormone analogue, Fenoxycarb on development and oxygen uptake by larval lobsters Homarus gammarus (L.).

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    Arnold, Katie E; Wells, Colin; Spicer, John I

    2009-04-01

    Little attention has been focused on the effect of anthropogenic compounds that disrupt the endocrine systems in crustaceans. Consequently, this study investigated the effects of the juvenile hormone analogue (JHA), Fenoxycarb on selected physiological and developmental processes of the zoeal stages in the European lobster, Homarus gammarus. Chronic exposure to Fenoxycarb (50microg L(-1)) resulted in a significant (p < 0.05) reduction in moult frequency and size at moult. Fenoxycarb exposure extended zoeal duration between zoea I to II (p<0.05) and resulted in total inhibition of the moult from zoea II to III. Significantly greater rates of O2 uptake were observed in Fenoxycarb-exposed larvae in comparison with controls (p<0.05). All rates of O2 uptake decreased significantly between 7 and 12d of exposure (p<0.05). At 12d, exposure to the solvent control no longer influenced rates of O2 uptake, but it was not possible to attribute increased O2 uptake to Fenoxycarb exposure directly, as treated individuals did not moult beyond zoea III. The low exposure concentrations of Fenoxycarb, comparable to those used in plant protection, resulted in endocrine disrupted responses in H. gammarus (albeit with little clear, demonstrable effect on metabolism) a finding that could have important ecological and commercial implications.

  14. Transfer across the human gut of environmental technetium in lobsters (Homarus gammarus L.) from the Irish Sea

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    Hunt, G.J. [The Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk NR33 0HT (United Kingdom)]. E-mail: g.j.hunt@cefas.co.uk; Young, A.K.; Bonfield, R.A. [The Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk NR33 0HT (United Kingdom)

    2001-03-01

    Few data are available on the uptake by the human gut of the element technetium. Of current radiological interest in connection with discharges of technetium-99 in liquid discharges from BNFL, Sellafield, is uptake from European lobsters (Homarus gammarus), whose edible parts are known to concentrate technetium. In this study, a group of eight adult volunteers (six males and two females) ate samples of edible flesh from lobsters caught off the west Cumbrian coast and provided 24 h samples of urine and faeces for analysis. Detection of uptake from the gut by difference between intake and faecal measurements proved insensitive, suggesting a low value of the gut transfer factor (f{sub 1} value) of up to 0.1 with a maximum (two standard deviations) level of about 0.3. In urine, technetium was detectable at a relatively low level compared with the intakes, consistent with a low absorption across the gut. Values for f{sub 1} were derived with the aid of literature data for excretion following intravenous administration of technetium-95m as pertechnetate, and gave averaged data for f{sub 1} in the range 0.046 to 0.23. These results are in broad conformity with those derived from the faecal measurements, and suggest a lower value than the 0.5 used by ICRP. (author)

  15. An Enriched Environment Promotes Shelter-Seeking Behaviour and Survival of Hatchery-Produced Juvenile European Lobster (Homarus gammarus)

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    Aspaas, Stian; Grefsrud, Ellen Sofie; Fernö, Anders; Jensen, Knut Helge; Trengereid, Henrik; Agnalt, Ann-Lisbeth

    2016-01-01

    The high loss of newly released hatchery-reared European lobster (Homarus gammarus) juveniles for stock enhancement is believed to be the result of maladaptive anti-predator behaviour connected to deprived stimuli in the hatchery environment. Our objective was to learn if an enriched hatchery environment enhances shelter-seeking behaviour and survival. In the “naïve” treatment, the juveniles were raised in single compartments without substrate and shelter whereas juveniles in the “exposed” treatment experienced substrate, shelter and interactions with conspecifics. Three experiments with increasing complexity were conducted. Few differences in shelter-seeking behaviour were found between treatments when one naïve or one exposed juvenile were observed alone. When observing interactions between one naïve and one exposed juvenile competing for shelter, naïve juveniles more often initiated the first aggressive encounter. The third experiment was set up to simulate a release for stock enhancement. Naïve and exposed juveniles were introduced to a semi-natural environment including substrate, a limited number of shelters and interactions with conspecifics. Shelter occupancy was recorded three times during a period of 35 days. Exposed juveniles occupied more shelters, grew larger and had higher survival compared with naïve juveniles. Our results demonstrate that experience of environmental complexity and social interactions increase shelter-seeking ability and survival in hatchery reared lobster juveniles. PMID:27560932

  16. An Enriched Environment Promotes Shelter-Seeking Behaviour and Survival of Hatchery-Produced Juvenile European Lobster (Homarus gammarus).

    Science.gov (United States)

    Aspaas, Stian; Grefsrud, Ellen Sofie; Fernö, Anders; Jensen, Knut Helge; Trengereid, Henrik; Agnalt, Ann-Lisbeth

    2016-01-01

    The high loss of newly released hatchery-reared European lobster (Homarus gammarus) juveniles for stock enhancement is believed to be the result of maladaptive anti-predator behaviour connected to deprived stimuli in the hatchery environment. Our objective was to learn if an enriched hatchery environment enhances shelter-seeking behaviour and survival. In the "naïve" treatment, the juveniles were raised in single compartments without substrate and shelter whereas juveniles in the "exposed" treatment experienced substrate, shelter and interactions with conspecifics. Three experiments with increasing complexity were conducted. Few differences in shelter-seeking behaviour were found between treatments when one naïve or one exposed juvenile were observed alone. When observing interactions between one naïve and one exposed juvenile competing for shelter, naïve juveniles more often initiated the first aggressive encounter. The third experiment was set up to simulate a release for stock enhancement. Naïve and exposed juveniles were introduced to a semi-natural environment including substrate, a limited number of shelters and interactions with conspecifics. Shelter occupancy was recorded three times during a period of 35 days. Exposed juveniles occupied more shelters, grew larger and had higher survival compared with naïve juveniles. Our results demonstrate that experience of environmental complexity and social interactions increase shelter-seeking ability and survival in hatchery reared lobster juveniles.

  17. Multi-annual fluctuations in reconstructed historical time-series of a European lobster (Homarus gammarus population disappear at increased exploitation levels.

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    Andreas Sundelöf

    Full Text Available Through the history of ecology, fluctuations of populations have been a dominating topic, and endogenous causes of fluctuations and oscillations have been recognized and studied for more than 80 years. Here we analyzed an historical dataset, covering more than 130 years, of European lobster (Homarus gammarus catches. The data shows periodic fluctuations, which are first dampened and then disappear over time. The disappearance of the periodicity coincided with a substantial increase in fishing effort and the oscillations have not reappeared in the time series. The shifting baseline syndrome has changed our perception of not only the status of the stock, but also the regulating pressures. We describe the transition of a naturally regulated lobster population into a heavily exploited fisheries controlled stock. This is shown by the incorporation of environmental and endogenous processes in generalized additive models, autocorrelation functions and periodicity analyses of time-series.

  18. The accumulation of plutonium by the European lobster (Homarus gammarus L.)

    International Nuclear Information System (INIS)

    Swift, D.J.

    1992-01-01

    For 237 Pu accumulation from seawater, the whole body concentration factors (CFs) for juvenile lobsters at 18 o C did not exceed 250 over the 49 days of the study. Most 237 Pu was accumulated by the gills and exoskeleton. Since homarid lobsters eat their exuviae after ecdysis, the whole body 237 Pu content of recently moulted lobsters was also a function of the amount of 237 Pu ingested with the exuviae. Consequently, organ/tissue content and CF values for individual lobsters reflected both the time since their last moult and their exposure time to 237 Pu. These factors precluded the calculation of mean whole body CF values or the accurate estimate of a mean steady state (C ss ) CF value. Juvenile lobsters retained significantly more 237 Pu from labelled food at 7-10 o C than at 18 o C. At 7 o C, the biological half time for assimilated 237 Pu was about 28 days, at 10 o C about 15 days and at 18 o C about 8 days. Very little 237 Pu was transported from the gut to the internal tissues (about 1%); most was retained in the hepatopancreas. (author)

  19. The accumulation of plutonium by the European lobster (Homarus gammarus L. )

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    Swift, D J [Ministry of Agriculture, Fisheries and Food, Lowestoft (United Kingdom). Directorate of Fisheries Research

    1992-01-01

    For {sup 237}Pu accumulation from seawater, the whole body concentration factors (CFs) for juvenile lobsters at 18{sup o}C did not exceed 250 over the 49 days of the study. Most {sup 237}Pu was accumulated by the gills and exoskeleton. Since homarid lobsters eat their exuviae after ecdysis, the whole body {sup 237}Pu content of recently moulted lobsters was also a function of the amount of {sup 237}Pu ingested with the exuviae. Consequently, organ/tissue content and CF values for individual lobsters reflected both the time since their last moult and their exposure time to {sup 237}Pu. These factors precluded the calculation of mean whole body CF values or the accurate estimate of a mean steady state (C{sub ss}) CF value. Juvenile lobsters retained significantly more {sup 237}Pu from labelled food at 7-10{sup o}C than at 18{sup o}C. At 7{sup o}C, the biological half time for assimilated {sup 237}Pu was about 28 days, at 10{sup o}C about 15 days and at 18{sup o}C about 8 days. Very little {sup 237}Pu was transported from the gut to the internal tissues (about 1%); most was retained in the hepatopancreas. (author).

  20. Accumulation of sup(95m)Tc from sea water by juvenile lobsters (Homarus gammarus L. )

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    Swift, D.J. (Ministry of Agriculture, Fisheries and Food, Lowestoft (UK). Directorate of Fisheries Research)

    1985-01-01

    The uptake and retention of technetium from sea water by juvenile lobsters, and the effects of moulting on these processes, has been studied using sup(95m)Tc as a tracer. Accumulation was rapid with whole body concentration factors of over 2000 being measured in some lobsters. Uptake was highest immediately before a moult; post-moult there was a fall in accumulation. No simple mathematical equation for technetium accumulation with time was found. The technetium concentration in the moulted exoskeleton increased with time of exposure of the lobsters but never exceeded 2% of the whole body value. The highest percentage of the whole body activity was found in the digestive gland; the green gland had the highest concentration factor. Technetium excretion, following 64 d of accumulation, could be expressed as an exponential rate of loss. The biological half-time was calculated as 53 d. Moulted exoskeletons from these lobsters contained approximately 0.6% of the day zero whole body activity.

  1. Susceptibility of juvenile European lobster Homarus gammarus to shrimp products infected with high and low doses of white spot syndrome virus.

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    Bateman, K S; Munro, J; Uglow, B; Small, H J; Stentiford, G D

    2012-08-27

    White spot syndrome virus (WSSV) is the most important pathogen known to affect the sustainability and growth of the global penaeid shrimp farming industry. Although most commonly associated with penaeid shrimp farmed in warm waters, WSSV is also able to infect, cause disease in and kill a wide range of other decapod crustaceans, including lobsters, from temperate regions. In 2005, the European Union imported US$500 million worth of raw frozen or cooked frozen commodity products, much of which originated in regions positive for white spot disease (WSD). The presence of WSSV within the UK food market was verified by means of nested PCR performed on samples collected from a small-scale survey of supermarket commodity shrimp. Passage trials using inoculum derived from commodity shrimp from supermarkets and delivered by injection to specific pathogen-free Pacific white shrimp Litopenaeus vannamei led to rapid mortality and pathognomonic signs of WSD in the shrimp, demonstrating that WSSV present within commodity shrimp was viable. We exposed a representative European decapod crustacean, the European lobster Homarus gammarus, to a single feeding of WSSV-positive, supermarket-derived commodity shrimp, and to positive control material (L. vannamei infected with a high dose of WSSV). These trials demonstrated that lobsters fed positive control (high dose) frozen raw products succumbed to WSD and displayed pathognomonic signs associated with the disease as determined by means of histology and transmission electron microscopy. Lobsters fed WSSV-positive, supermarket-derived commodity shrimp (low dose) did not succumb to WSD (no mortality or pathognomonic signs of WSD) but demonstrated a low level or latent infection via PCR. This study confirms susceptibility of H. gammarus to WSSV via single feedings of previously frozen raw shrimp products obtained directly from supermarkets.

  2. A Comparative Study of the Uptake, Clearance and Metabolism of Technetium in Lobster (Homarus Gammarus) and Edible Crab (Cancer Paguras)

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    Knowles, J.F.; Smith, D.L.; Winpenny, K

    1998-07-01

    Lobsters and edible crabs have been exposed to {sup 95}Tc{sup m} in their sea water or in their food, and the uptake, retention and distribution of the isotope in their bodies examined. The steady-state concentration factor C{sub ss} for uptake of {sup 95}Tc{sup m} from sea water was significantly greater for female crabs (C{sub ss}=17.9) than for males (C{sub ss}=14.4). There was no such sex difference in lobsters and they took up {sup 95}Tc{sup m} to much higher levels with a C{sub ss} of 1160. Retention of the isotope was similar for crabs and lobsters and for animals of both sexes. However the route of uptake was important with more rapid clearance after uptake from sea water (t{sub b1/2} = 51 days) than after uptake from food (t{sub b1/2} = 108 days). Technetium was found predominantly in the hepatopancreas of all crabs and most male lobsters. In a few male lobsters and all females it was mainly in muscle. Lobster ovaries consistently contained more activity than testes but this difference was not seen in crabs. At the subcellular level {sup 95}Tc{sup m} in hepatopancreas cells of both lobster and crab occurred mainly in the cytosol. Results of initial studies into the relationships between technetium and cytosol proteins are given and the possible basis for the much greater accumulation of the element by lobsters than crabs discussed. (author)

  3. The accumulation of sup(95m)Tc from sea water by juvenile lobsters (Homarus gammarus L.)

    International Nuclear Information System (INIS)

    Swift, D.J.

    1985-01-01

    The uptake and retention of technetium from sea water by juvenile lobsters, and the effects of moulting on these processes, has been studied using sup(95m)Tc as a tracer. Accumulation was rapid with whole body concentration factors of over 2000 being measured in some lobsters. Uptake was highest immediately before a moult; post-moult there was a fall in accumulation. No simple mathematical equation for technetium accumulation with time was found. The technetium concentration in the moulted exoskeleton increased with time of exposure of the lobsters but never exceeded 2% of the whole body value. The highest percentage of the whole body activity was found in the digestive gland; the green gland had the highest concentration factor. Technetium excretion, following 64 d of accumulation, could be expressed as an exponential rate of loss. The biological half-time was calculated as 53 d. Moulted exoskeletons from these lobsters contained approximately 0.6% of the day zero whole body activity. (author)

  4. Effect of temperature on the mortality and growth of the lobster (Homarus gammarus L. ) in its first year

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    Danielssen, D S; Iversen, S A [Statens Biologiske Stasjon, Floedevigen (Norway)

    1976-01-01

    Experiments were carried out with newly hatched lobster larvae at temperatures of 12/sup 0/, 14/sup 0/, 16/sup 0/, 18/sup 0/, 20/sup 0/ and 22/sup 0/C. After about two months the constant temperature of 14/sup 0/C was changed to a fluctuating temperature corresponding to that at a depth of 20m outside the station, which should simulate as closely as possible the lobsters' natural temperature environment in the sea. The initial temperature shock did not seem to cause increased mortality during the first few days. Seen over the whole experiment period, the mortality was greatest at 12/sup 0/C and at the natural temperature. A temperature difference of 2/sup 0/C between the individual batches was sufficient to give a significant time difference from hatching to the fourth stage. The frequency of moulting fell with falling temperature and increasing number of moults. Even at the same temperature there were great individual differences in rates of growth.

  5. Hatchery production of European lobster (Homarus gammarus, L.: broodstock management and effects of different holding systems on larval survival

    Directory of Open Access Journals (Sweden)

    Rodolfo Ballestrazzi

    2010-01-01

    Full Text Available The biometry of wild berried females was collected during an entire reproductive season at the South-Wexford Lobster Co-op hatchery in Nethertown, Ireland. Second degree regressions between total body weight (TW, g and carapace length (CL, mm (TW=CL2 -36.675CL+1793.2, R2=0.9022 and number of “weaned” larvae and carapace length (Larvae number=1.217CL2–21.777CL-5281.1, R2 =0.743 were observed. Afterwards, berried females were divided according to two variables: 1. holding system: recirculating system (Rs vs barrel (Bar; 2. CL size: 120 mm (C. The total weight of larvae (212.5 vs 92.4 g and their numbers (7788 vs 5679 were significantly higher for the largest females than for the smaller sizes (P<0.01. The maximum survival rate of larvae (77.86% was noted for initial stocking density <1000 individuals/hopper, but the optimal stocking density for management purposes in the hatchery is higher (2001-3000 individuals/hopper.

  6. An experimental study of americium-241 biokinetics in the Lobster Homarus Gammarus. Analysis of the accumulation/storage and detoxification processes at the subcellular level

    International Nuclear Information System (INIS)

    Paquet, F.

    1993-01-01

    An experimental study of americium-241 kinetics has been conducted in the lobster Homarus gammmarus. The investigations were conducted at all the levels from the whole body to the subcellular and molecular levels. The animals were contaminated by a single or chronic ingestion of 241 Am labelled mussels. Assessments of accumulation, elimination and distribution of the radionuclide were established on organisms kept in the laboratory; they made it possible to demonstrate the importance of the digestive gland in the radionuclide transfer pathways. The preliminary results led to structural then ultrastructural investigations of the digestive gland in association with radioautographic studies and cellular extractions methods. Four cellular types were demonstrated, only two of them being implied in the radionuclide retention, the former being responsible for americium intake and the latter for its long-term retention. By means of biochemical techniques, subcellular accumulation was studied and the organelles implied in the nuclide retention were specified. Finally, a method of cellular nuclei dissociation was developed; it made it possible to analyse the molecular nature of americium ligands and to demonstrate the function of the protein nuclear matrix in the nuclide retention

  7. Biokinetics of a transuranic (238PU) and a rare earth element (152Eu) in the lobster (Homarus gammarus): transfer mechanisms (accumulation and detoxification) in organs and at the cellular level

    International Nuclear Information System (INIS)

    Tocquet, N.

    1995-01-01

    The work presented here is an experimental investigation of the biokinetics of transfer of a transuranic and a rare earth element ( 238 Pu and 152 Eu) in the lobster Homarus gammarus. The study of 238 Pu biokinetics forms part of a wider framework of research concerning the transfer of transuranic elements in marine species, while the study of 152 Eu is carried out with a view to supporting the analogy between the behaviour of transuranics and rare earths in living organisms. Exactly the same experimental protocol, based on techniques from various disciplines (biology, biochemistry and metrology), was used to Investigate the biokinetics of transfer of these two radionuclides. The Individual lobsters were radiolabelled by means of one-shot or chronic ingestion of spiked meals. As the first approach, the kinetics and transfer mechanisms were studied In whole animal samples and in different organs distinct series of pathways through the different organs were identified in the case of both radionuclides, being mainly linked to digestive processes induced by the meal as well as the transport function of hemo-lymph in this way, the Important role of the digestive gland was picked out, with two of four cellular types displaying a successive involvement In the fixation and then the retention of the studied radionuclides. As a corroborative approach, the digestive gland was subjected to a more detailed investigation with the aim of describing the mechanisms of Incorporation and elucidating transfer processes at the cellular and molecular levels. 238 Pu is preferentially partitioned into the cytosol, where it is associated with various constituents such as ferritin (iron-storing protein). 152 Eu is more diffusely distributed in the hepato-pancreatic cells, while the lysosomes appear to play a more important role during transfer. The results obtained in this study, both on the macroscopic scale (i.e. the whole animal and different organs) as well as the cellular and molecular

  8. The accumulation, retention and distribution of 95mTc in crab (Cancer pagurus L.) and lobster (Homarus gammarus L.). A comparative study

    International Nuclear Information System (INIS)

    Smith, D.L.; Knowles, J.F.; Winpenny, K.

    1988-01-01

    The accumulation, retention and distribution of 95m Tc has been compared in lobsters and edible crabs kept under identical experimental conditions. The steady-state concentration factor (C ss ) for the uptake of 95m Tc from seawater was significantly greater for female crabs (C ss =17·9) than for males (C ss =14·4), whereas in lobsters there was no such sex difference and the C ss of 1161 was much greater than in crabs. The uptake of technetium from food (as indicated by whole body counts) was only moderately greater in lobsters than crabs. Retention of 95m Tc was similar for crabs and lobsters of both sexes but the clearance rate was greater after the nuclide had been taken up from seawater (t b1/2 =51 days) than from food (t b1/2 =108 days). In all crabs and most male lobsters 95m Tc was predominantly in the hepatopancreas while in a few male and all female lobsters it was mainly in muscle. Lobster ovaries consistently contained more activity than testes but this difference was not seen in crabs. In hepatopancreas cells of both species 95m Tc occurred mainly in the cytosol and some initial steps were taken to determine the relationship between technetium and cytosol proteins. The results for crab and lobster are compared with those from previous studies on these and other crustacean species. The possible basis for the much higher concentrations of technetium in lobsters than crabs is discussed and further research suggested. (Copyright (c) 1988 Elsevier Science B.V., Amsterdam. All rights reserved.)

  9. The accumulation, retention and distribution of {sup 95m}Tc in crab (Cancer pagurus L.) and lobster (Homarus gammarus L.). A comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Smith, D L; Knowles, J F; Winpenny, K [The Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory, Pakefield Road, Lowestoft, Suffolk (United Kingdom)

    1988-08-01

    The accumulation, retention and distribution of {sup 95m}Tc has been compared in lobsters and edible crabs kept under identical experimental conditions. The steady-state concentration factor (C{sub ss}) for the uptake of {sup 95m}Tc from seawater was significantly greater for female crabs (C{sub ss}=17{center_dot}9) than for males (C{sub ss}=14{center_dot}4), whereas in lobsters there was no such sex difference and the C{sub ss} of 1161 was much greater than in crabs. The uptake of technetium from food (as indicated by whole body counts) was only moderately greater in lobsters than crabs. Retention of {sup 95m}Tc was similar for crabs and lobsters of both sexes but the clearance rate was greater after the nuclide had been taken up from seawater (t{sub b1/2}=51 days) than from food (t{sub b1/2}=108 days). In all crabs and most male lobsters {sup 95m}Tc was predominantly in the hepatopancreas while in a few male and all female lobsters it was mainly in muscle. Lobster ovaries consistently contained more activity than testes but this difference was not seen in crabs. In hepatopancreas cells of both species {sup 95m}Tc occurred mainly in the cytosol and some initial steps were taken to determine the relationship between technetium and cytosol proteins. The results for crab and lobster are compared with those from previous studies on these and other crustacean species. The possible basis for the much higher concentrations of technetium in lobsters than crabs is discussed and further research suggested. (Copyright (c) 1988 Elsevier Science B.V., Amsterdam. All rights reserved.)

  10. Experimental study of Americium-241 biokinetics in Homarus Gammarus lobster. Analysis of the accumulation and detoxication mechanisms at the sub-cellular level

    International Nuclear Information System (INIS)

    Paquet, F.

    1991-12-01

    The Americium 241 radioelement accumulation and elimination rate and mechanisms in the lobster organism have been experimentally studied; incorporation and detoxification capacities of each organ are evaluated. The existence of various biological compartments is shown; the major role of the digestive gland in accumulation of the radioelement, its distribution towards the various organs, and its resorption is comprehensively described, with an analysis at the subcellular and molecular levels. 401 p., 65 fig., 43 tab., 428 ref

  11. Suspension feeding in adult Nephrops norvegicus (L.) and Homarus gammarus (L.) (decapoda)

    Science.gov (United States)

    Loo, Lars-Ove; Pihl Baden, Susanne; Ulmestrand, Mats

    Suspension feeding in adults of the Norway lobster Nephrops norvegicus (40-74 g) and the European lobster Homarus gammarus (280-350 g) was tested in experiments offering planktonic food items of different sizes from 200 to 600 μm and measuring the clearing capacity. Both lobster species were found to effectively clear water of food particles comprising nauplii of the brine shrimp Artemia salina of about 600 μm in size. These were reduced to 50% of the initial concentration within 5 h and to 90% within 12 h. When N. norvegicus was offered food particles averaging 200 μm, a significant reduction in average size occurred, indicating that the minimum retention size is around 200 μm. Fluorescently dyed Artemia salina were recovered in the stomach and intestine of lobsters proving that the filtered particles are passed to the digestive tract. Results from other experiments, using the blood pigment (haemocyanin) concentration as an index of nutritional state, indicated that the lobsters can get some nutritional advantage from suspension feeding. Suspension feeding in larger decapods has not been described previously, so the significance of this finding is discussed with respect to changes in behavioural and ecological role.

  12. Biokinetics of a transuranic ({sup 238}PU) and a rare earth element ({sup 152}Eu) in the lobster (Homarus gammarus): transfer mechanisms (accumulation and detoxification) in organs and at the cellular level; Biocinetiques d'un element transuranien, le {sup 238}PU, et d'une terre rare, le {sup 152}EU, chez le homard homarus gammarus (organes et niveau cellulaire) modalites des transferts (accumulation et detoxication)

    Energy Technology Data Exchange (ETDEWEB)

    Tocquet, N

    1995-07-01

    The work presented here is an experimental investigation of the biokinetics of transfer of a transuranic and a rare earth element ({sup 238}Pu and {sup 152}Eu) in the lobster Homarus gammarus. The study of {sup 238}Pu biokinetics forms part of a wider framework of research concerning the transfer of transuranic elements in marine species, while the study of {sup 152}Eu is carried out with a view to supporting the analogy between the behaviour of transuranics and rare earths in living organisms. Exactly the same experimental protocol, based on techniques from various disciplines (biology, biochemistry and metrology), was used to Investigate the biokinetics of transfer of these two radionuclides. The Individual lobsters were radiolabelled by means of one-shot or chronic ingestion of spiked meals. As the first approach, the kinetics and transfer mechanisms were studied In whole animal samples and in different organs distinct series of pathways through the different organs were identified in the case of both radionuclides, being mainly linked to digestive processes induced by the meal as well as the transport function of hemo-lymph in this way, the Important role of the digestive gland was picked out, with two of four cellular types displaying a successive involvement In the fixation and then the retention of the studied radionuclides. As a corroborative approach, the digestive gland was subjected to a more detailed investigation with the aim of describing the mechanisms of Incorporation and elucidating transfer processes at the cellular and molecular levels. {sup 238}Pu is preferentially partitioned into the cytosol, where it is associated with various constituents such as ferritin (iron-storing protein). {sup 152}Eu is more diffusely distributed in the hepato-pancreatic cells, while the lysosomes appear to play a more important role during transfer. The results obtained in this study, both on the macroscopic scale (i.e. the whole animal and different organs) as well

  13. Biokinetics of a transuranic ({sup 238}PU) and a rare earth element ({sup 152}Eu) in the lobster (Homarus gammarus): transfer mechanisms (accumulation and detoxification) in organs and at the cellular level; Biocinetiques d'un element transuranien, le {sup 238}PU, et d'une terre rare, le {sup 152}EU, chez le homard homarus gammarus (organes et niveau cellulaire) modalites des transferts (accumulation et detoxication)

    Energy Technology Data Exchange (ETDEWEB)

    Tocquet, N

    1995-07-01

    The work presented here is an experimental investigation of the biokinetics of transfer of a transuranic and a rare earth element ({sup 238}Pu and {sup 152}Eu) in the lobster Homarus gammarus. The study of {sup 238}Pu biokinetics forms part of a wider framework of research concerning the transfer of transuranic elements in marine species, while the study of {sup 152}Eu is carried out with a view to supporting the analogy between the behaviour of transuranics and rare earths in living organisms. Exactly the same experimental protocol, based on techniques from various disciplines (biology, biochemistry and metrology), was used to Investigate the biokinetics of transfer of these two radionuclides. The Individual lobsters were radiolabelled by means of one-shot or chronic ingestion of spiked meals. As the first approach, the kinetics and transfer mechanisms were studied In whole animal samples and in different organs distinct series of pathways through the different organs were identified in the case of both radionuclides, being mainly linked to digestive processes induced by the meal as well as the transport function of hemo-lymph in this way, the Important role of the digestive gland was picked out, with two of four cellular types displaying a successive involvement In the fixation and then the retention of the studied radionuclides. As a corroborative approach, the digestive gland was subjected to a more detailed investigation with the aim of describing the mechanisms of Incorporation and elucidating transfer processes at the cellular and molecular levels. {sup 238}Pu is preferentially partitioned into the cytosol, where it is associated with various constituents such as ferritin (iron-storing protein). {sup 152}Eu is more diffusely distributed in the hepato-pancreatic cells, while the lysosomes appear to play a more important role during transfer. The results obtained in this study, both on the macroscopic scale (i.e. the whole animal and different organs) as well

  14. An experimental study of americium-241 biokinetics in the Lobster Homarus Gammarus. Analysis of the accumulation/storage and detoxification processes at the subcellular level; Etude experimentale des biocinetiques de l`americium-241 chez le homard homarus gammarus. Analyse des mecanismes d`accumulation et de detoxication au niveau subcellulaire

    Energy Technology Data Exchange (ETDEWEB)

    Paquet, F

    1993-01-01

    An experimental study of americium-241 kinetics has been conducted in the lobster Homarus gammmarus. The investigations were conducted at all the levels from the whole body to the subcellular and molecular levels. The animals were contaminated by a single or chronic ingestion of {sup 241} Am labelled mussels. Assessments of accumulation, elimination and distribution of the radionuclide were established on organisms kept in the laboratory; they made it possible to demonstrate the importance of the digestive gland in the radionuclide transfer pathways. The preliminary results led to structural then ultrastructural investigations of the digestive gland in association with radioautographic studies and cellular extractions methods. Four cellular types were demonstrated, only two of them being implied in the radionuclide retention, the former being responsible for americium intake and the latter for its long-term retention. By means of biochemical techniques, subcellular accumulation was studied and the organelles implied in the nuclide retention were specified. Finally, a method of cellular nuclei dissociation was developed; it made it possible to analyse the molecular nature of americium ligands and to demonstrate the function of the protein nuclear matrix in the nuclide retention.

  15. Structural characterization of recombinant crustacyanin subunits from the lobster Homarus americanus

    International Nuclear Information System (INIS)

    Ferrari, Michele; Folli, Claudia; Pincolini, Elisa; McClintock, Timothy S.; Rössle, Manfred; Berni, Rodolfo; Cianci, Michele

    2012-01-01

    The two recombinant apo subunits H1 and H2 from H. americanus have been structurally characterized. Reconstitution studies with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits. Crustacean crustacyanin proteins are linked to the production and modification of carapace colour, with direct implications for fitness and survival. Here, the structural and functional properties of the two recombinant crustacyanin subunits H 1 and H 2 from the American lobster Homarus americanus are reported. The two subunits are structurally highly similar to the corresponding natural apo crustacyanin CRTC and CRTA subunits from the European lobster H. gammarus. Reconstitution studies of the recombinant crustacyanin proteins H 1 and H 2 with astaxanthin reproduced the bathochromic shift of 85–95 nm typical of the natural crustacyanin subunits from H. gammarus in complex with astaxanthin. Moreover, correlations between the presence of crustacyanin genes in crustacean species and the resulting carapace colours with the spectral properties of the subunits in complex with astaxanthin confirmed this genotype–phenotype linkage

  16. Experimental study of Americium-241 biokinetics in Homarus Gammarus lobster. Analysis of the accumulation and detoxication mechanisms at the sub-cellular level; Etude experimentale des biocinetiques de l`americium-241 chez le homard homarus gammarus. Analyse des mecanismes d`accumulation et de detoxication au niveau subcellulaire

    Energy Technology Data Exchange (ETDEWEB)

    Paquet, F

    1991-12-01

    The Americium 241 radioelement accumulation and elimination rate and mechanisms in the lobster organism have been experimentally studied; incorporation and detoxification capacities of each organ are evaluated. The existence of various biological compartments is shown; the major role of the digestive gland in accumulation of the radioelement, its distribution towards the various organs, and its resorption is comprehensively described, with an analysis at the subcellular and molecular levels. 401 p., 65 fig., 43 tab., 428 ref.

  17. Contributions for larval development optimization of Homarus gammarus

    Directory of Open Access Journals (Sweden)

    Pedro Tiago Fonseca Sá

    2014-06-01

    The seawater rising temperature resulted in a decrease of intermoult period in all larval development stages and at all tested temperatures, ranging from 4.77 (Z1 to 16.5 days (Z3 at 16°C, whereas at 23°C, ranged from 3:02 (Z1 and 9.75 days (Z3. The results obtained are an extremely useful guide for future optimization of protocols on larval development of H. gammarus.

  18. Epizootic shell disease in American lobsters Homarus americanus in southern New England: past, present and future.

    Science.gov (United States)

    Castro, Kathleen M; Cobb, J Stanley; Gomez-Chiarri, Marta; Tlusty, Michael

    2012-08-27

    The emergence of epizootic shell disease in American lobsters Homarus americanus in the southern New England area, USA, has presented many new challenges to understanding the interface between disease and fisheries management. This paper examines past knowledge of shell disease, supplements this with the new knowledge generated through a special New England Lobster Shell Disease Initiative completed in 2011, and suggests how epidemiological tools can be used to elucidate the interactions between fisheries management and disease.

  19. Effect of copper on the characterization of proteins in the Spiny lobster, Panulirus homarus homarus (Linnaeus,1758

    Directory of Open Access Journals (Sweden)

    Maharajan Athisuyambulingam

    2014-07-01

    Full Text Available Copper is most toxic metal in marine organisms. Characterization of protein occurring in the metabolically active tissues of muscle (MU, hepatopancreas (HP and gills (GL of the spiny lobster, Panulirus homarus homarus on exposure to two sub-lethal doses (9.55 and 19.1 µg/l of copper were studied for 28 days of exposure (DoE. The electrophoretic pattern of muscle, hepatopancreas and gill proteins revealed 12, 8 and 8 slow moving bands (control. The number of bands decreased to 8 and 7, 6 and 5, 6 and 4 after 7 days of exposure to 9.55 µg/l and 19.1 µg/l concentrations of copper, respectively. After 28 days, the protein bands decreased to 7 and 6, 5 and 4, 4 and 4 at 9.55 µg/l and 19.1 µg/l concentrations of copper, respectively. Present study to indicate that to avoid the Cupro-Nickel coil in lobster holding centers in chiller plants used for cooling of water was found to be responsible for the mortality of lobsters during live transportation.

  20. Bait and the susceptibility of American lobsters Homarus americanus to epizootic shell disease.

    Science.gov (United States)

    Bethoney, N David; Stokesbury, Kevin D E; Stevens, Bradley G; Altabet, Mark A

    2011-05-24

    Shell disease (SD) has been observed in lobster populations for almost a hundred years, but recently, rates of an epizootic form of shell disease (ESD) have increased in the southern New England (USA) area. A large proportion of fish in the diet of American lobsters Homarus americanus has been linked to increased rates of SD. Therefore, the use of fish as lobster bait may be linked to increased ESD rates in lobsters. Lobsters from the western portion of Martha's Vineyard, MA (41 degrees N, 71 degrees W), were randomly divided into 3 groups of 16 and exposed to dietary treatments (100% herring; 48% crab, 48% blue mussel and 4% plant matter; or 50% herring, 24% crab, 24% mussel, 2% plant matter) to determine if lobster tissue delta15N levels reflected diet. The results of the feeding experiment confirmed that differences in diet are observed in the delta15N levels of lobster muscle tissue. The delta15N levels of tissue samples from 175 wild lobsters with varying degrees of ESD were unrelated to ESD severity but did indicate lobsters were eating large amounts of fish (bait). This result does not support the speculation that fish used as bait is contributing to ESD outbreaks in portions of the southern New England area.

  1. Chemosensitivity of walking legs of the lobster Homarus americanus: neurophysiological response spectrum and thresholds

    Energy Technology Data Exchange (ETDEWEB)

    Derby, C D; Atema, J

    1982-01-01

    Responses of chemoreceptors in the walking legs of the lobster Homarus americanus to 35 individual compounds and 3 mixtures (prey odours and extracts) were studied using extracellular recording techniques. Compared against a standard mussel (Mytilus edulis) extract, these receptors were most sensitive to the amino acids L-glutamate, hydroxy-L-proline, L-aspartate, L-arginine, glycine, taurine, and L-alanine, as well as such other compounds as ammonium chloride, betaine, and the tripeptide glutathione. Most of these excitants are among those compounds most prevalent in the prey of lobsters.

  2. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

    Directory of Open Access Journals (Sweden)

    Luz A. Avila-Villa

    2012-01-01

    Full Text Available Necrotizing hepatopancreatitis bacterium (NHPB is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo.

  3. Experimental Infection and Detection of Necrotizing Hepatopancreatitis Bacterium in the American Lobster Homarus americanus

    Science.gov (United States)

    Avila-Villa, Luz A.; Gollas-Galván, Teresa; Martínez-Porchas, Marcel; Mendoza-Cano, Fernando; Hernández-López, Jorge

    2012-01-01

    Necrotizing hepatopancreatitis bacterium (NHPB) is an obligated intracellular bacteria causing severe hepatopancreatic damages and mass mortalities in penaeid shrimp. The worldwide distribution of penaeid shrimp as alien species threatens the life cycle of other crustacean species. The aim of the experiment was to evaluate the possibility of experimentally infecting the American lobster (Homarus americanus) with NHPB extracted from shrimp hepatopancreas. Homogenates from infected shrimp were fed by force to lobsters. Other group of lobsters was fed with homogenates of NHPB-free hepatopancreas. After the 15th day from initial inoculation, the presence of NHPB was detected by polymerase chain reaction in feces and hepatopancreas from lobsters inoculated with infected homogenates. Necrotized spots were observed in the surface of lobster hepatopancreas. In contrast, lobsters fed on NHPB-free homogenates resulted negative for NHPB. Evidence suggests the plasticity of NHPB which can infect crustacean from different species and inhabiting diverse latitudes. Considering the results, the American lobster could be a good candidate to maintain available NHPB in vivo. PMID:22645497

  4. Factors affecting post-capture survivability of lobster Homarus americanus.

    Science.gov (United States)

    Basti, David; Bricknell, Ian; Hoyt, Ken; Chang, Ernest S; Halteman, William; Bouchard, Deborah

    2010-06-11

    Technological advances in gear and fishing practices have driven the global expansion of the American lobster live seafood market. These changes have had a positive effect on the lobster industry by increasing capture efficiency. However, it is unknown what effect these improved methods will have on the post-capture fitness and survival of lobsters. This project utilized a repeated measures design to compare the physiological changes that occur in lobsters over time as the result of differences in depth, hauling rate, and storage methodology. The results indicate that lobsters destined for long distance transport or temporary storage in pounds undergo physiological disturbance as part of the capture process. These changes are significant over time for total hemocyte counts, crustacean hyperglycemic hormone, L-lactate, ammonia, and glucose. Repeated measures multivariate analysis of variance (MANOVA) for glucose indicates a significant interaction between depth and storage methodology over time for non-survivors. A Gram-negative bacterium, Photobacterium indicum, was identified in pure culture from hemolymph samples of 100% of weak lobsters. Histopathology revealed the presence of Gram-negative bacteria throughout the tissues with evidence of antemortem edema and necrosis suggestive of septicemia. On the basis of these findings, we recommend to the lobster industry that if a reduction in depth and hauling rate is not economically feasible, fishermen should take particular care in handling lobsters and provide them with a recovery period in recirculating seawater prior to land transport. The ecological role of P. indicum is not fully defined at this time. However, it may be an emerging opportunistic pathogen of stressed lobsters. Judicious preemptive antibiotic therapy may be necessary to reduce mortality in susceptible lobsters destined for high-density holding facilities.

  5. Diseases of American lobsters (Homarus americanus): a review.

    Science.gov (United States)

    Cawthorn, Richard J

    2011-01-01

    The American lobster fishery is a significant economic driver in coastal communities of North America. Increasingly, the impacts of infectious disease are recognized as important components and factors in the population ecology and subsequent management of the lobster fishery. Both environmental and anthropogenic factors impact marine diseases. The review herein highlights aspects of several important bacterial, fungal and protistan diseases, including gaffkemia, shell disease, vibriosis, disease caused by species of Lagenidium, Haliphthoros and Fusarium, paramoebiasis and Bumper Car disease. As the global environment continues to change, these diseases could more severely affect both wild caught and impounded lobsters. Copyright © 2010 Elsevier Inc. All rights reserved.

  6. RESPON IMUNITAS BENIH LOBSTER, Panulirus homarus DENGAN PENGGUNAAN PROBIOTIK PADA PAKAN MOIST

    Directory of Open Access Journals (Sweden)

    Haryanti Haryanti

    2017-05-01

    Full Text Available Pemeliharaan benih lobster P. homarus masih menghadapi beberapa permasalahan, di antaranya infeksi penyakit bakteri (red body disease dan mortalitas yang tinggi. Tujuan penelitian ini adalah untuk mengkaji respons imunitas benih lobster P. homarus yang diberi pakan pelet basah (moist diets dengan penambahan probiotik. Pemeliharaan benih lobster dilakukan secara individu (1 ekor/keranjang. Lama pemeliharaan selama tiga bulan. Bobot awal puerulus P. homarus adalah 0,37 ± 0,05 g. Perlakuan meliputi pemberian pakan moist yang ditambahkan (A ragi Saccharomyces cerevisiae, (B kombinasi probiotik, Alteromonas sp. BY-9 dan Bacillus cereus BC, dan (C tanpa probiotik. Respons imunitas dianalisis dengan RT-qPCR melalui tujuh gen target terkait ekspresi imunitas, setelah diuji tantang dengan Vibrio harveyi (penyebab red body disease. Hasil penelitian menunjukkan bahwa sintasan benih lobster sebesar (A 32,22%; (B 29,63%; dan (C 33,33%. Pertumbuhan panjang dan bobot benih lobster tidak berbeda nyata (P>0,05. Respons imunitas benih lobster P. homarus pada perlakuan A dan B menunjukkan nilai ekspresi imun yang lebih tinggi dibandingkan dengan perlakuan C (tanpa probiotik. Ekspresi gen penyandi anti lipopolisakarida (ALFHa-1 meningkat pada (A rata-rata sebesar 3,44 kali dan (B 3,25 kali dibandingkan dengan perlakuan C (2,43 kali. Kelipatan ekspresi profenoloksidase (proPO benih lobster meningkat pada perlakuan A (penambahan ragi rata-rata sebesar 5,27 kali, sedangkan pada perlakuan B (kombinasi probiotik sebesar 12,92 kali. Ekspresi Clotting sistem (transglutaminase, clotting protein dan antioxidant defense mechanism (glutathione peroxidase/GPO dan SAA juga mengalami peningkatan pada perlakuan A dan B. A number of contrains including disease infections and significant mortality have been occurring in lobster aquaculture. The aim of this research was to observe the immune response of juvenile lobster P. homarus culture fed by moist pellet supplemented with

  7. Predation on hatchery-reared lobsters released in the wild

    OpenAIRE

    van der Meeren, Gro

    2000-01-01

    Predation on hatchery-reared lobsters (Homarus gammarus) in the wild was studied in order to identify predators in southwestern Norway on rocky and sandy substrates in winter and summer. Lobsters of 12–15 mm carapace length were tagged with magnetic microtags. About 51 000 juvenile lobsters were released on 10 occasions at three locations. Predator samplings were by trammel nets, eel traps, and videorecordings during the 24 h immediately following the releases. In summer, loss to ...

  8. Gas pipelines and the American lobster, Homarus americanus

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, R.A. [Connecticut Univ., Groton, CT (United States); Clancy, M. [Boston Univ., MA (United States); Cobb, J.S. [Rhode Island Univ., Kingston, RI (United States)

    2003-07-01

    One of the main objectives of the megabenthic study of the New England continental shelf conducted during the 1970s and the 1980s was to define the migratory behavior and overall ecology of the offshore American lobster. The study involved more than 100 manned submersible divers on the outer continental shelf, upper continental slope, Georges Bank and submarine canyons. It also included an extensive lobster tagging program. The study provided valuable information on the ecology and behaviour of the lobster and several other megabenthic fauna that could be affected by the presence of a gas pipeline running parallel to the outer continental shelf, from eastern Georges Bank to northern New Jersey. The study showed that an exposed 2-4 diameter pipeline would impede the normal onshore and offshore migration of this deep water lobster species because its' migration is done by walking rather than swimming, and any overhanging structure would block its path. It was emphasized that it is extremely important to maintain spring to early summer onshore migration in the multi-million dollar lobster industry. This paper offered suggestions for modifying pipe encasements to solve the migration problem.

  9. Excretory calcinosis: a new fatal disease of wild American lobsters Homarus americanus.

    Science.gov (United States)

    Dove, Alistair D M; LoBue, Carl; Bowser, Paul; Powell, Mark

    2004-03-10

    A significant number of moribund and dead lobsters Homarus americanus were reported to New York state authorities by lobster fishers in Long Island Sound (LIS) during the summer of 2002. Morbid lobsters were characterised by an orange discolouration of the abdomen, lethargy, an excess of epibionts and poor post-capture survival. On necropsy, severe extensive multifocal or diffuse mineralised granulomatous inflammation of the gills and antennal glands was the most striking pathology. In the gills, granulomas often occluded the lumen of filaments, resulting in congestion, ischemia and coagulative necrosis of gill tissues. In the antennal glands, granulomas were concentrated along the border between the coelomosac and labyrinth. No significant pathogens were recovered from diseased individuals. In prechronic individuals, however, it was evident that granulomas were focused around calcium carbonate (aragonite) crystals. This disease may result from anomalously high sea-bottom temperatures in LIS (approximately 23 degrees C) during the summer of 2002 and associated disruptions of the calcium chemistry of lobsters in favour of deposition of minerals in soft tissues. The ultimate cause of death of affected lobsters is probably respiratory failure due to reduced effective surface area of the gills, exacerbated by hypermetabolic temperatures and an abundance of epibionts.

  10. PERBEDAAAN PADAT TEBAR TERHADAP TINGKAT PERTUMBUHAN DAN KELANGSUNGAN HIDUP POST PEURULUS LOBSTER PASIR (Panulirus homarus PADA BAK TERKONTROL

    Directory of Open Access Journals (Sweden)

    Nunik Cokrowati

    2012-10-01

    Full Text Available Prospek budidaya Panulirus homarus menjanjikan dari segi ekonomi dan keadaan alam di wilayah NTB serta merupakan spesies komoditi ekspor utama di Indonesia.Potensi akuakultur lobster pasir tentunya membutuhkan teknik budidaya yang sesuai agar mendapatkan hasil yang optimal.Tujuan penelitian ini adalah untuk mengetahui perbedaan padat tebar terhadap pertumbuhan dan nilai Survival rate (SR serta untuk mengetahui padat tebar yang dapat menghasilkan pertumbuhan dan nilai SR optimum post puerulus Panulirus homarus.Metode yang digunakan dalam penelitian ini adalah metode eksperimental dengan menggunakan Rancangan Acak Lengkap (RAL dengan faktor tunggal yaitu padat tebar dengan densitas 20 ekor/m2, 40 ekor/m2, 60 ekor/m2, dan 80 ekor/m2. Parameter yang diamati adalah pertumbuhan spesifik dan kelangsungan hidup (SR post puerulus Panulirus homarus. Hasil penelitian menunjukkan bahwa pemberian perlakuan perbedaan padat tebar berpengaruh (P<0,05 terhadap pertumbuhan spesifik dan kelangsungan hidup (SR post puerulus Panulirus homarus. Nilai SGR dan SR tertinggi terdapat pada kepadatan 20 ekor/m2 sebesar 2,15425% dengan nilai SR 75%, dengan kualitas air sebagai faktor pembatas dengan nilai rata-rata pH 7,2, suhu 26,930 C, salinitas 34,4 ppt dan DO 5,86 mg/l nilai tersebut dalam batas toleransi  sebagai kehidupan biota air khususnya  lobster pasir. Kata kunci : Panulirus homarus, padat tebar, survival rate

  11. American Lobsters (Homarus Americanus) not Surviving During Air Transport: Evaluation of Microbial Spoilage.

    Science.gov (United States)

    Tirloni, Erica; Stella, Simone; Gennari, Mario; Colombo, Fabio; Bernardi, Cristian

    2016-04-19

    Eighteen American lobsters ( Homarus americanus ), dead during air transport, were analysed in order to evaluate the microbial population of meat, gills and gut: no specific studies have ever been conducted so far on the microbiological quality of American lobsters' meats in terms of spoilage microbiota. The meat samples showed very limited total viable counts, in almost all the cases below the level of 6 Log CFU/g, while higher loads were found, as expected, in gut and gills, the most probable source of contamination. These data could justify the possibility to commercialise these not-surviving subjects, without quality concerns for the consumers. Most of the isolates resulted to be clustered with type strains of Pseudoalteromonas spp. (43.1%) and Photobacterium spp. (24.1%), and in particular to species related to the natural marine environment. The distribution of the genera showed a marked inhomogeneity among the samples. The majority of the isolates identified resulted to possess proteolytic (69.3%) and lipolytic ability (75.5%), suggesting their potential spoilage ability. The maintanance of good hygienical practices, especially during the production of ready-to-eat lobsters-based products, and a proper storage could limit the possible replication of these microorganisms.

  12. TOTAL HEMOCYTE COUNT AND HEMOLYMPH GLUCOSE CONCENRATION RESPONSE OF SPINY LOBSTER Panulirus homarus ON RATIO OF SHELTER

    Directory of Open Access Journals (Sweden)

    Suhaiba Djai

    2017-11-01

    Full Text Available This research was conducted to assess the physiological response of the lobster Panulirus homarus for the ratio of the shelters. The method used completely randomized design with two replicates of each treatments with shelter ratio (A 1 : 5, (B 3 : 5, (C 4 : 5, (D 5 : 5. Weight average for 184 lobsters with the stocking density of 23 lobsters for each treatment was 32.64 ± 0.58 g. The experiment was conducted for 60 days. The lobster was fed with trash fish and acclimatized for 7 days before the experiment. Observations on the physiologycal of every 10 days. The physiological responses that observed were total hemocyte count (THC and hemolymph glucose concentration. The results showed that 4:5 was the best lobster shelter ratio because it could reduce stress levels. This is indicated by the stable values of THC and hemolymph glucose level during the experiment and supported by the growth of 57.28 ± 0.15 g and survival rate of 91.31 ± 2.60%. Keywords: lobster, Panulirus homarus, ratio, shelter, THC, glucose

  13. Temperature increase can cause hyperecdysonism in American lobsters (Homarus americanus) injected with ecdysterone

    Energy Technology Data Exchange (ETDEWEB)

    Aiken, D E; Waddy, S L

    1975-10-01

    In the lobster Homarus americanus the threshold dose for premolt acceleration by ecdysterone can be altered by changes in temperature. Two dose levels of ecdysterone (0.5 and 1.0 ..mu..g/g body weight) were compared at three different temperatures (10, 17, 21/sup 0/C); all three doses remained subthreshold at 10/sup 0/C but at 17/sup 0/C the 1.0-..mu..g dose caused hyperecdysonism--rapid but abnormal completion of premolt terminating in death at ecdysis. In contrast, the 0.5-..mu..g dose remained subthreshold even at 21/sup 0/C. These results demonstrate a dose-temperature relation for response to injected ecdysterone.

  14. American lobsters (Homarus americanus not surviving during air transport: evaluation of microbial spoilage

    Directory of Open Access Journals (Sweden)

    Erica Tirloni

    2016-05-01

    Full Text Available Eighteen American lobsters (Homarus americanus, dead during air transport, were analysed in order to evaluate the microbial population of meat, gills and gut: no specific studies have ever been conducted so far on the microbiological quality of American lobsters’ meats in terms of spoilage microbiota. The meat samples showed very limited total viable counts, in almost all the cases below the level of 6 Log CFU/g, while higher loads were found, as expected, in gut and gills, the most probable source of contamination. These data could justify the possibility to commercialise these notsurviving subjects, without quality concerns for the consumers. Most of the isolates resulted to be clustered with type strains of Pseudoalteromonas spp. (43.1% and Photobacterium spp. (24.1%, and in particular to species related to the natural marine environment. The distribution of the genera showed a marked inhomogeneity among the samples. The majority of the isolates identified resulted to possess proteolytic (69.3% and lipolytic ability (75.5%, suggesting their potential spoilage ability. The maintanance of good hygienical practices, especially during the production of ready-to-eat lobsters-based products, and a proper storage could limit the possible replication of these microorganisms.

  15. Effects of starvation on moult cycle and hepatopancreas of Stage I lobster (Homarus americanus) larvae

    Science.gov (United States)

    Anger, K.; Storch, V.; Anger, V.; Capuzzo, J. M.

    1985-06-01

    Effects of feeding and starvation on the moult cycle and on the ultrastructure of hepatopancreas cells were studied in Stage I lobster larvae ( Homarus americanus Milne-Edwards). The relative significance of yolk and first food was quite different in larvae originating from two females. This difference was evident also in the amounts of stored lipid in the R-cells of the larval hepatopancreas. Most larvae from one hatch were, in principle, able to develop exclusively with yolk reserves (without food) to the second instar. The larvae from the second hatch showed lecithotrophic development only to the transition between late intermoult and early premoult (Stages C/D0 of Drachs's moult cycle) of the first larval instar. When initial starvation in this group lasted for 3 days or more, the point of no return (PNR) was exceeded. After the PNR, consumption of food was still possible, but development ceased in the transition C/D0 or in late premoult (D3 4). It is suggested that these stages of the moult cycle are critical points were cessation of development and increased mortality are particularly likely in early larval lobsters under nutritional stress. Examination of hepatopancreas R-cells suggested that the PNR is caused by an irreversible loss of the ability to restore lipid reserves depleted during initial starvation. Initial periods of starvation ending before the PNR prolonged mainly Stage D0 of the same instar (I). During this delay, structural changes in the R-cells caused by the preceding period of starvation were reversed: reduced lipid inclusions, swollen mitochondria, an increased number of residual bodies indicating autolysis, and a reduction of the microvillous processes. Continually starved larvae which showed lecithotrophic development throughout the first instar and were then re-fed after moulting successfully, had later a prolonged intermoult (Stage C) period in the second instar. This shows that, despite occasional lecithotrophy, food is an important

  16. Induced resistance to infection of lobsters Homarus americanus by Aerococcus viridans (var.) homari, the bacterium causing gaffkemia.

    Science.gov (United States)

    Stewart, James E; Arie, B; Marks, L J

    2004-12-13

    A vaccine composed of steam sterilized (autoclaved) cells of a virulent strain of Aerococcus viridans (var.) homari was effective in protecting lobsters Homarus americanus against gaffkemia. At 15 degrees C the heat-killed vaccines (HKV) at concentrations between 1 and 5 x 10(7) particles kg(-1) lobster body wt induced maximal protection in induction periods ranging from 7 to 11 d. Protection was substantial over the course of a 30 d post-induction trial period. Spring-caught lobsters (i.e. those more fully rehabilitated following ecdysis) gained more protection (LD50 = 1.9 x 10(4)) from the vaccination than did those caught in the late fall-early winter period (lobsters that were not yet fully recovered from ecdysis) (LD50 = 3.2 x 10(3)). The protection offered by the HK vaccine was comparable to that induced by a vaccine produced by incubating the pathogen with low concentrations (2 pg ml(-1)) of the antibiotic vancomycin. The bacterins produced by both methods exhibited similar new properties: (1) agglutination at low titres by lobster hemolymph serum, suggesting an impaired capsule layer, and (2) increased permeability to the large Alcian Blue molecule. With both vaccines, the protection may be a direct result of increased exposure to intact bacterial cell structures by the lobster defences, an exposure which otherwise would be prevented by an intact capsule.

  17. Ranking harbours in the maritime provinces of Canada for potential to contaminate American lobster (Homarus americanus) with polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Prouse, N.J.

    1994-01-01

    Polycyclic aromatic hydrocarbons (PAHs) comprise a suite of contaminants that enter the marine environment through a variety of natural and anthropogenic sources. PAHs, including carcinogenic compounds, bioaccumulate in the tissues of exposed American lobsters (Homarus americanus). High PAH concentrations in lobster tissues necessitated the closure of the lobster fishery in the South Arm of Sydney Harbour, Nova Scotia, in 1982. A study was conducted to assess harbors in Nova Scotia, New Brunswick, and Prince Edward Island to determine if there might be a reason for concern about PAH contamination of lobsters. Adjacent commercial and industrial activity, harbor uses, the surrounding population, and PAH point sources were evaluated for each harbor selected for study. Areas of lobster fishing and the number of permanent lobster holding facilities within each harbor were also determined. Harbors were then ranked according to their potential for PAH contamination. Point sources for PAHs within these harbors included petroleum and coal products plants, oil refineries, chemical plants, coal-fired generating stations, and fuel combustion in land vehicles and ships. After Sydney, the harbors with the highest potential for PAH contamination were determined to be Halifax, Saint John, Pictou, and Port Hawkesbury Ship Harbour. 60 refs., 15 figs., 7 tabs.

  18. Effect of confinement and starvation on stress parameters in the American lobster (Homarus americanus

    Directory of Open Access Journals (Sweden)

    Edo D'Agaro

    2014-12-01

    Full Text Available The American lobster (Homarus americanus is one of the most important crustacean resources in North America. In Italy and Europe, this fishery product is available throughout the year and it has a high and increasing commercial demand. American lobsters are traditionally marketed live and stocked, without feed, in temperature controlled recirculating systems for several weeks before being sold in the market places. The current Italian legislation does not fix a maximum length of time for the crustacean confinement and specific welfare requirements. In the present research, a 4-week experiment was carried out using 42 adult H. americanus reared in 4 recirculating aquaculture tanks. After one month of confinement, mean glucose, protein and total haemocyte count levels in the hemolymph of H. americanus were stable and similar (P>0.05 to the values observed at the beginning of the experiment. Results of the proximate analysis of the abdominal muscles of H. americanus showed no significant differences in concentrations of crude protein, lipid and ash during the trial. At the end of the experiment, the sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting analysis revealed a marked degradation of the muscle myofibrillar proteins. A number of fragments, possibly from myosin, were evident in the range between 50 and 220 kDa between time t0 and t28. Results of this study show that the main hemolymphatic variables and degradation analysis of the muscle myofibrillar proteins can be used as sensitive indicators of the crustacean stress response to confinement and starvation.

  19. Influence of natural inshore and offshore thermal regimes on egg development and time of hatch in American lobsters, Homarus americanus.

    Science.gov (United States)

    Goldstein, Jason S; Watson, Winsor H

    2015-02-01

    Some egg-bearing (ovigerous) American lobsters (Homarus americanus) make seasonal inshore-to-offshore movements, subjecting their eggs to different thermal regimes than those of eggs carried by lobsters that do not make these movements. Our goal was to determine if differences in thermal regimes influence the rate of egg development and the subsequent time of hatch. We subjected ovigerous lobsters to typical inshore or offshore water temperatures from September to August in the laboratory (n=8 inshore and 8 offshore, each year) and in the field (n=8 each, inshore and offshore), over 2 successive years. Although the rate of egg development did not differ significantly between treatments in the fall (P∼0.570), eggs exposed to inshore thermal regimes developed faster in the spring (Plobsters exposed to offshore thermal regimes accumulated more GDD in the winter than did eggs carried by inshore lobsters, while eggs exposed to inshore temperatures acquired them more rapidly in the spring. Results suggest that seasonal movements of ovigerous lobsters influence the time and location of hatching, and thus the transport and recruitment of larvae to coastal and offshore locations. © 2015 Marine Biological Laboratory.

  20. Low-salinity stress in the American lobster, Homarus americanus, after chronic sublethal exposure to cadmium: Biochemical effects

    Energy Technology Data Exchange (ETDEWEB)

    Gould, E

    1980-01-01

    Lobsters (Homarus americanus) were exposed to cadmium (6 ..mu..g 1sup(-1), 30 days) in flowing seawater, then held for 7 days in aerated 'clean' seawater at either ambient (27 per mill) or low (17 per mill) salinity. Cadmium exposure alone (ambient salinity) induced a general elevation of enzyme activity (heart, antennal gland, and muscle MDH; heart LDH and GPI), despite the probability of some clearance of cadmium from body tissues during the 'clean' seawater holding period. Low-salinity alone (non-exposed lobsters) caused a decrease of enzyme activity (AAT, LDH, GPI, PK) in most tissues examined, except for tail muscle IDH, the activity of which was increased, and MDH, which was significantly elevated above ambient controls in all tissues except heart. Most low-salinity effects were observed in tail muscle, and most cadmium effects, in heart; low-salinity effects outnumbered cadmium stress by nine to four. In heart and tail muscle of cadmium-exposed lobsters held at low salinity, each of the two stresses apparently operated to nullify the other's effects. The most prominent single biochemical response to these sublethal stresses was the elevation of MDH activity. The ratio MDH:LDH gave the clearest indication of overall relative stress.

  1. Tainting and depuration of taint by lobsters (Homarus americanus) exposed to water contaminated with a No.2 Fuel Oil: Relationship with aromatic hydrocarbon content in tissue

    International Nuclear Information System (INIS)

    Williams, U.P.; Kiceniuk, J.W.; Fancey, L.L.; Botta, J.R.

    1989-01-01

    Lobsters (Homarus americanus) were exposed to a pulse of diesel oil and held for 21 days to depurate. Taste panels revealed a highly significant difference between samples, as well as a preferences for, the untreated samples at days 10 and 11. The odor of the raw treated samples differed significantly from that of the control at each of the sampling times. Cooking appeared to remove the oily odor from the raw lobster. Significantly elevated concentrations of total aromatics were found in the hepatopancreas of both sexes at days 3-4 and 10-11 and in the tail muscle of male and female lobsters 10-11 days after initial exposure and decreased thereafter. Tainting of lobsters can occur within 10 days of exposure to diesel, and this effect can be reversed within 20 days after initial exposure

  2. Effect of natural and laboratory diet on O : N ratio in juvenile lobsters (Homarus americanus).

    Science.gov (United States)

    Brown, Anne Christine

    2006-05-01

    Oxygen consumption and ammonia excretion rates of juvenile lobsters spanning the size range from shelter-restricted to vagile (7-60 mm CL, carapace length) were measured. There are no significant size-dependent break points in the slope of oxygen consumption or nitrogen excretion rates versus weight in freshly caught wild or laboratory fed lobsters. This suggests that there are no inherent changes in energy metabolism in juvenile lobster in the 7-60 mm CL range (stage V to adolescent lobsters), despite major behavioral shifts related to foraging and shelter use. In addition, the O : N ratio of freshly caught wild lobsters (15.7+/-7.4, mean+/-S.D.) is not significantly different from that of lobsters fed brown algae (13.4+/-4.9) or a mixed carbohydrate/protein diet (13.7+/-6.8) in lab. The O : N ratio of wild lobsters is significantly higher than lobsters fed a high protein diet (7.5+/-2.5) in the lab. This suggests that carbohydrates, particularly algal-derived carbohydrates, make up a significant portion of the metabolic fuel of wild juvenile lobsters from settlement through adolescence.

  3. Influence of drilling muds on the primary chemosensory neurons in walking legs of the lobster, Homarus americanus

    Energy Technology Data Exchange (ETDEWEB)

    Derby, C D; Atema, J

    1981-01-01

    The effects of whole drilling muds on the normal activity of walking leg chemosensory neurons of the lobster, Homarus americanus, were examined using extracellular neurophysiological recording techniques. Exposure of legs for 3-5 min to 10 mg/L drilling mud suspended in seawater altered responses to food odors of 29% of the chemoreceptors examined (data pooled for the two drilling muds tested); similar exposure to 100 mg/L drilling mud resulted in interference with 44% of all receptors studied. The effects of both of these concentrations are statistically significant, although they are not different from each other. Interference was usually manifested as a marked reduction in the number of action potentials in a response. In one preparation, the exposure to drilling mud caused a change in the temporal pattern of the spikes without affecting the total number of spikes. Other chemosensory neurons were excited by 10 mg/L drilling mud itself. However, not all chemoreceptors are inhibited by these drilling muds since responses to feeding stimuli were recorded from the legs of lobsters that had been exposed to drilling mud for 4-8 d before the neurophysiological experiments. Antennular and leg chemoreceptors are important in eliciting normal feeding behavior in lobsters. Although behavioral assays have demonstrated that feeding behavior is altered following exposure to drilling muds and petroleum fractions, there is no conclusive proof for a causal relationship between chemoreceptor interference and behavior deficits. The two techniques complement each other as pollution detection assays, perhaps reflecting a common interference mechanism. 42 references, 4 figures, 2 tables.

  4. Ulcerative enteritis in Homarus americanus: case report and molecular characterization of intestinal aerobic bacteria of apparently healthy lobsters in live storage.

    Science.gov (United States)

    Battison, Andrea L; Després, Béatrice M; Greenwood, Spencer J

    2008-10-01

    An intermoult male American lobster, Homarus americanus, with severe intestinal lesions was encountered while collecting samples of aerobic intestinal bacteria from lobsters held in an artificial sea-water recirculation aquarium system. Grossly, the intestine was firm, thickened, and white. Histologic examination revealed a severe, diffuse, ulcerative enteritis which spared the chitin-lined colon, somewhat similar to hemocytic enteritis of shrimp. The bacterial isolates from this lobster were compared to 11 other lobsters lacking gross intestinal lesions. Two organisms, one identified as Vibrio sp. and another most similar to an uncultured proteobacterium (98.9%), clustering with Rhanella and Serratia species using 16S rDNA PCR, were isolated from the intestines of the 11, grossly normal, lobsters and the affected lobster. An additional two intestinal isolates were cultured only from the lobster with ulcerative enteritis. One, a Flavobacterium, similar to Lutibacter litoralis (99.3%), possibly represented a previously described commensal of the distal intestine. The second, a Vibrio sp., was unique to the affected animal. While the etiology of the ulcerative enteritis remains undetermined, this report represents the first description of gross and histologic findings in H. americanus of a condition which has morphologic similarities to hemocytic enteritis of shrimp. An additional observation was a decrease in the number of intestinal isolates recovered from the 11 apparently healthy lobsters compared to that previously reported for recently harvested lobster. More comprehensive studies of the relationship between the health of lobsters, gut microbial flora and the husbandry and environment maintained within holding units are warranted.

  5. DISTRIBUSI UKURAN DAN PARAMETER POPULASI LOBSTER PASIR (Panulirus homarus DI PERAIRAN ACEH BARAT

    Directory of Open Access Journals (Sweden)

    Duranta D Kembaren

    2015-12-01

    Full Text Available Penelitian tentang distribusi ukuran dan parameter populasi lobster pasir di perairan Aceh Barat dilakukan pada bulanApril sampai November 2013. Penelitian ini bertujuan untukmengkaji status lobster di perairan Aceh Barat dilihat dari aspek distribusi ukuran dan parameter populasinya. Pengamatan dan pengukuran lobster dilakukan di tempat pengumpul lobster dengan sistem sampling acak. Sebaran frekuensi panjang karapas selanjutnya ditabulasikan dan dianalisa dengan metode kurva logistik. Struktur ukuran lobster yang tertangkap menunjukkan bahwa lobster jantan dominan tertangkap dibawah ukuran nilai tengah 72,5 mm dan sebaliknya diatas ukuran nilai tengah 72,5 mm yang didominasi jenis kelamin betina. Lobster terlebih dahulu tertangkap sebelum mencapai ukuran matang gonad (Lc = 65,8mm< Lm= 76,8 mm. Puncak musim pemijahan terjadi pada bulan Mei dan Agustus. Panjang asimtosis (CL∞  sebesar 119,5 mm dengan laju pertumbuhan (K 0,39/tahun serta laju kematian total (Z 1,44/tahun, laju kematian alamiah (M 0,67/tahun dan laju keamatian akibat penangkapan (F 0,77/tahun. Laju eksploitasi sudah mengarah kepada penangkapan yang berlebih (E=0,54, oleh karena itu perlu dilakukan tindakan pengelolaan perikanan lobster yang berkelanjutan. Salah satu upaya yang dapat di tempuh adalah dengan menerapkan sistem penutupan musim penangkapan lobster pada saat terjadinya puncak musim pemijahan. Research on the length distribution and population parameters of scalloped spiny lobster conducted in the Aceh Barat waters during April to November 2013. The aim of this study was to assess lobster fishery status in this waters from the point of view their length size and population parameters. Sampel collected randomly in the lobster landing site. Distribution of carapace length frequency was tabulated and analysed using logistic curve method. Length composition of male lobster was dominated under 72,5 mm midlenght, while female lobster was dominated above 72

  6. Relationship between dose of emamectin benzoate and molting response of ovigerous American lobsters (Homarus americanus).

    Science.gov (United States)

    Waddy, S L; Merritt, V A; Hamilton-Gibson, M N; Aiken, D E; Burridge, L E

    2007-05-01

    A widely-prescribed treatment to control sea lice on cultured salmon is the administration of feed medicated with SLICE (active ingredient emamectin benzoate (EMB)). High doses of EMB can disrupt the molt cycle of ovigerous American lobsters, causing them to enter proecdysis prematurely and lose their attached eggs when the shell is cast. To determine the dose response to EMB, lobsters were forced to ingest doses that ranged from 0.05 to 0.39 microg g(-1). A significant proportion of lobsters given doses of 0.39 and 0.22 microg g(-1) (37% and 23%, respectively) molted prematurely, almost a year earlier than the control group. All the lobsters in the 0.05 and 0.12 microg g(-1) groups molted at the normal time and the mean time of molt was similar to that of the control group. Thus, the no-observed-effect level (NOEL) and lowest-observed-effect level (LOEL) of EMB on the molt cycle were 0.12 and 0.22 microg EMB g(-1) lobster, respectively. To acquire the LOEL, a 500-g lobster would have to consume 22 g of salmon feed medicated with SLICE at a level of 5 microg EMB g(-1) feed.

  7. Combined toxicity of free chlorine, chloramine, and temperature to stage 1 larvae of the American lobster Homarus americanus

    Energy Technology Data Exchange (ETDEWEB)

    Capuzzo, J M; Lawrence, S A; Davidson, J A

    1976-01-01

    The differential effects of free chlorine and chloramine on stage I larvae of the American lobster Homarus americanus have been investigated in continuous flow bioassay units. Applied chloramine was more toxic than corresponding concentrations of applied free chlorine to lobster larvae with estimated LC/sub 50/ values at 25/sup 0/ of 16.30 mg/l applied free chlorine and 2.02 mg/l applied chloramine. The synergistic effect of temperature on the toxicity of both free chlorine and chloramine has also been demonstrated. Exposure to applied free chlorine at 20/sup 0/ resulted in no significant mortality of test organisms, whereas exposure at 30/sup 0/ resulted in an estimated LC/sub 50/ value of 2.50 mg/l. Applied chloramine was considerably more toxic with an estimated LC/sub 50/ value at 20/sup 0/ of 4.08 mg/l and at 30/sup 0/ of 0.56 mg/l. The action of each toxicant appeared to be an alteration of standard metabolic activity as revealed by changes in respiration rates during and after exposure to applied free chlorine and chloramine. Initial respiratory stress was detected during exposure to 0.05 mg/l applied chloramine and 5.00 mg/l applied free chlorine. Reductions in respiration rates 48 h after exposure were observed with exposure to all concentrations tested, similar results being obtained following exposure to 0.05 mg/l applied chloramine and 0.10 mg/l applied free chlorine. These results are indicative of the need for information in addition to that obtained in standard bioassays for an adequate assessment of chlorine toxicity.

  8. A noninvasive method for in situ determination of mating success in female American lobsters (Homarus americanus).

    Science.gov (United States)

    Goldstein, Jason S; Pugh, Tracy L; Dubofsky, Elizabeth A; Lavalli, Kari L; Clancy, Michael; Watson, Winsor H

    2014-02-07

    Despite being one of the most productive fisheries in the Northwest Atlantic, much remains unknown about the natural reproductive dynamics of American lobsters. Recent work in exploited crustacean populations (crabs and lobsters) suggests that there are circumstances where mature females are unable to achieve their full reproductive potential due to sperm limitation. To examine this possibility in different regions of the American lobster fishery, a reliable and noninvasive method was developed for sampling large numbers of female lobsters at sea. This method involves inserting a blunt-tipped needle into the female's seminal receptacle to determine the presence or absence of a sperm plug and to withdraw a sample that can be examined for the presence of sperm. A series of control studies were conducted at the dock and in the laboratory to test the reliability of this technique. These efforts entailed sampling 294 female lobsters to confirm that the presence of a sperm plug was a reliable indicator of sperm within the receptacle and thus, mating. This paper details the methodology and the results obtained from a subset of the total females sampled. Of the 230 female lobsters sampled from George's Bank and Cape Ann, MA (size range = 71-145 mm in carapace length), 90.3% were positive for sperm. Potential explanations for the absence of sperm in some females include: immaturity (lack of physiological maturity), breakdown of the sperm plug after being used to fertilize a clutch of eggs, and lack of mating activity. The surveys indicate that this technique for examining the mating success of female lobsters is a reliable proxy that can be used in the field to document reproductive activity in natural populations.

  9. Effects of an oil spill on American lobster (Homarus americanus) from Placentia Bay, Newfoundland

    Energy Technology Data Exchange (ETDEWEB)

    Wiliams, U P; Kiceniuk, J W; Ryder, J E; Botta, J R

    1988-10-01

    In March 1988 an accidental spill of ca 500 bbl of crude oil occurred during the unloading of a tanker at a Newfoundland oil refinery. Studies of selected parameters were undertaken to determine the possible short-and long-term effects on the local lobster fishery. Sensory analyses were carried out to ascertain the effects of the oil on the taste and odor of lobster. Lobster muscle and hepatopancreas were analyzed for PAH (polycyclic aromatic hydrocarbon) content and levels of gill browning were determined. Sediments were sampled at various locations in the bay where the spill occurred and levels of PAHs were determined in an attempt to delineate the extent of contamination. Results from the sensory analyses indicate that there was no tainting of lobster samples obtained from the area. There was also no evidence of gill browning or of elevated levels of PAHs in either tail muscle or hepatopancreas. Elevated levels of PAH were not detected in any of the sediments from the bay. The results indicate that lobsters were not contaminated as a result of the oil spill. Based on the results of analyses of sediments for PAHs, future contamination, as a result of the spill at the oil refinery wharf, is not anticipated. 18 refs., 6 tabs.

  10. Function of chemoreceptor organs in spatial orientation of the lobster, Homarus americanus: differences and overlap

    Energy Technology Data Exchange (ETDEWEB)

    Devine, D.V.; Atema, J.

    1982-08-01

    Three of the lobster's main chemoreceptor organs, the lateral and medial antennules (representing smell) and the dactylus-propodus segments of the walking legs (representing taste), are physiologically quite similar. The authors examined their role in spatial orientation in a food-odor stimulus field. Control animals almost always oriented correctly and immediately to an odor plume. Lobsters with unilateral ablations of lateral antennules lost this ability, but did not show preferential turning toward the intact side. Unilateral medial antennule ablation did not affect orientation. Removal of all aesthetasc hairs from one lateral antennule caused loss of orientation ability less severe than unilateral ablation of the entire lateral antennule. Lobsters with unilaterally ablated lateral antennules and blocked walking leg receptors turned preferentially toward the side of the intact antennule. Thus, it appears that intact lobsters orient in odor space by tropotaxis principally using aesthetasc receptor input. Since loss of appendages is relatively common in lobsters, this partial overlap of organ function may serve the animal well in nature.

  11. Mechanisms of peripheral phylogeographic divergence in the indo-Pacific: lessons from the spiny lobster Panulirus homarus.

    Science.gov (United States)

    Farhadi, Ahmad; Jeffs, Andrew G; Farahmand, Hamid; Rejiniemon, Thankappan Sarasam; Smith, Greg; Lavery, Shane D

    2017-08-18

    There is increasing recognition of the concordance between marine biogeographic and phylogeographic boundaries. However, it is still unclear how population-level divergence translates into species-level divergence, and what are the principal factors that first initiate that divergence, and then maintain reproductive isolation. This study examines the likely forces driving population and lineage divergences in the broadly-distributed Indo-Pacific spiny lobster Panulirus homarus, which has peripheral divergent lineages in the west and east. The study focuses particularly on the West Indian Ocean, which is emerging as a region of unexpected diversity. Mitochondrial control region (mtCR) and COI sequences as well as genotypes of 9 microsatellite loci were examined in 410 individuals from 17 locations grouped into 7 regions from South Africa in the west, and eastward across to Taiwan and the Marquesas Islands. Phylogenetic and population-level analyses were used to test the significance and timing of divergences and describe the genetic relationships among populations. Analyses of the mtCR revealed high levels of divergence among the seven regions (Ф ST  = 0.594, P Indo-Pacific that helps drive some of the regions' recognized biogeographic boundaries.

  12. Narrow-spectrum chemoreceptor cells in the walking legs of the lobster Homarus americanus: taste specialists

    Energy Technology Data Exchange (ETDEWEB)

    Derby, C D; Atema, J

    1982-01-01

    The chemoreceptors in the legs of lobsters function in the localization and handling of food. By single-unit extracellular recording techniques, the specificity of single primary chemoreceptor cells is described here in detail. In contrast to what is known in vertebrates, narrow-spectrum chemoreceptors of several different types were found, each type responding with maximal sensitivity to only one of the following compounds: L-glutamate, L-glutamine, L-arginine, taurine, betaine, and ammonium chloride. Ammonium chloride sensitive cells were also highly specific. Other groups of narrow-spectrum cells - L-arginine, L-glutamine, taurine, and betaine sensitive chemoreceptors - showed equally strong specificity. These results indicate that the peripheral coding system in the legs of lobsters is based largely but perhaps not exclusively on narrow-spectrum chemoreceptor cells.

  13. Function of chemo- and mechanoreceptors in lobster (Homarus americanus) feeding behavior

    Energy Technology Data Exchange (ETDEWEB)

    Derby, C D; Atema, J

    1982-01-01

    The behavior of lobsters preying on live mussels (Mytilus edulis) was observed before and after chemosensory-mechanosensory deafferentation of different sensory appendages. Deafferentation of the antennules, leg tips, or maxillipeds (but not the carapace or proximal leg segments) interfered with feeding performance by causing an increase in the time necessary to crush a mussel after search initiation. In addition, deafferentation of the leg tips or the maxillipeds caused a decline in number of mussels crushed but for different reasons. Deafferentation of leg chemoreceptors resulted in the same behavioural deficiencies as deafferentation of leg chemo- and mechanoreceptors, demonstrating that it is the leg chemoreceptors that are essential in releasing this grasping response. Chemoreceptors on different appendages of lobsters therefore fulfill different functional roles in their feeding behavior.

  14. Experimental Rearing of Spiny Lobster, Panulirus homarus (Palinuridae in Land-Based Tanks at Mirbat Station (Sultanate of Oman in 2009-2010

    Directory of Open Access Journals (Sweden)

    Mohammed Balkhair

    2012-01-01

    Full Text Available Two experiments on the rearing of the spiny lobster Panulirus homarus were conducted in land-based tanks at Mirbat Aquaculture Unit from June to December 2009 and January-December 2010. In the first experiment 14 lobsters with an average size of 64.9±7.4 mm CL and weight of 297.8±98.0 g were reared to an average of 71.7±7.2 mm CL and weight of 384.0±114.8 g over 187 days. In the second experiment 45 lobsters were reared from an initial length of 45.4±4.6 mm CL and weight of 118.9 g to a length 66.0±7.1 mm CL and a weight of 304.1 g over 335 days. Total length increment was 45.8% and weight increment 155.1%. The daily food ration was 3.0-8.8%. The survival rate in the first experiment was 92.9%, in the second experiment it was also high (86.7% during the first six months. In both experiments males grew faster than females. While the water temperature, pH, salinity and dissolved oxygen reflected the ambient condition of the Arabian Sea, these were not optimal levels for lobsters culture. The salinity was higher (37.5 ppt, while the water temperature was low (<20oC during the summer monsoon. The study demonstrated the possibility of cultivating sub-adult lobsters in Oman from 40–45 mm CL and 100 g to maturity stage, obtaining the legal size of 70 mm CL and a weight of about 350 g over a year. It is recommended that the next experiment be conducted in floating sea cages from October to June.

  15. Estimating analytical variance in measurement of polycyclic aromatic hydrocarbons and application to monitoring in American lobster (Homarus americanus)

    Energy Technology Data Exchange (ETDEWEB)

    King, T.L.; Uthe, J.F.; Misra, R.K. [Department of Fisheries and Oceans, Halifax, NS (Canada). Biological Sciences Branch; Musial, C.J. [C. Musial Consulting Chemist Ltd., Monticello, MS (United States)

    1997-05-01

    Polycyclic aromatic hydrocarbon (PAH) concentration in American lobster was monitored. A method to estimate replicate PAH concentrations in the digestive gland tissue based on recoveries of added perdeutered surrogates from a single analysis was presented. Large variations in PAH concentrations were found among the different lobsters, even in specimens from the same place taken at the same time. PAH concentrations in lobsters were sensitive to animal size, sex and fishing site.

  16. Effects of drilling muds on behavior of the American lobster, Homarus americanus, in water column and substrate exposures

    Energy Technology Data Exchange (ETDEWEB)

    Atema, J; Leavitt, D F; Barshaw, D E; Cuomo, M C

    1982-01-01

    Studies were conducted to explore the effects of drilling muds on various aspects of lobster behavior directly related to survival in the field. Toxicity of different drilling muds varied from immediately lethal to adult lobsters to apparently harmless to postlarval stages, with a variety of intermediate effects. Both the chemical toxicity in the water column and the physical effects of covering the substrate with drilling mud were studied, and both interfered with normal lobster behavior. The studies are mainly concerned with postlarval lobsters (stages IV and V), just after settling on the bottom. They were tested in 36-d chronic exposures (7 mg/L) and in seminatural aquaria with 1-mm layers of drilling mud covering the substrate. Toxicity in the water column manifested itself in feeding and molting delays, severe delays in shelter construction, increased walking and swimming, unprovoked tail flipping, and lethargy. A natural bay mud used as a control caused no such effects. Physical effects of substrate cover were apparent in experiments with 1-, 2-, and 4-mm layers of drilling mud and similar layers of a mixture of bentonite and barite covering a natural mud substrate. In depths of 4mm both kinds of substrate cover caused severe delays in shelter construction and in quality of burrows constructed. Thus, substrates with 4-mm to perhaps as little as 1-mm covering of drilling mud may cause increased exposure of lobsters to predators and currents, resulting in the substrate becoming unsuitable for lobster settling and survival.

  17. Cuticles of European and American lobsters harbor diverse bacterial species and differ in disease susceptibility.

    Science.gov (United States)

    Whitten, Miranda M A; Davies, Charlotte E; Kim, Anita; Tlusty, Michael; Wootton, Emma C; Chistoserdov, Andrei; Rowley, Andrew F

    2014-06-01

    Diseases of lobster shells have a significant impact on fishing industries but the risk of disease transmission between different lobster species has yet to be properly investigated. This study compared bacterial biofilm communities from American (Homarus americanus) and European lobsters (H. gammarus), to assess both healthy cuticle and diseased cuticle during lesion formation. Culture-independent molecular techniques revealed diversity in the bacterial communities of cuticle biofilms both within and between the two lobster species, and identified three bacterial genera associated with shell lesions plus two putative beneficial bacterial species (detected exclusively in healthy cuticle or healing damaged cuticle). In an experimental aquarium shared between American and European lobsters, heterospecific transmission of potentially pathogenic bacteria appeared to be very limited; however, the claws of European lobsters were more likely to develop lesions when reared in the presence of American lobsters. Aquarium biofilms were also examined but revealed no candidate pathogens for environmental transmission. Aquimarina sp. 'homaria' (a potential pathogen associated with a severe epizootic form of shell disease) was detected at a much higher prevalence among American than European lobsters, but its presence correlated more with exacerbation of existing lesions rather than with lesion initiation. © 2014 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  18. Polycyclic aromatic hydrocarbon contamination of American lobster, Homarus americanus, in the proximity of a coal-coking plant

    Energy Technology Data Exchange (ETDEWEB)

    Uthe, J F; Musial, C J

    1986-11-01

    Polycyclic aromatic hydrocarbons (PAH) are ubiquitous environmental contaminants resulting predominantly from anthropogenic pyrolytic and combustion processes. In addition to the usual methods of aerial and aqueous transport to the coastal marine environment substantial amounts of PAH are added through the use of products such as creosote, coal tar and coal tar pitch as preservative and antifouling agents in the marine environment. Many PAH compounds are known carcinogenic agents and are rapidly taken up by fish and shellfish from water. Therefore as human foodstuffs many of these shellfish species warrant monitoring for PAH. A study of PAH in lobster tissues has been carried out using lobsters captured in Sydney harbour, Nova Scotia, Canada. Two coal-coking ovens on the shore have discharged their liquid effluents into the harbour. Lobsters from this area were sampled in 1982 and 1984. This paper presents the materials and methods used in the sampling, the results and discussion of them. The results confirmed the ability of lobsters to accumulate extremely high amounts of PAH in their tissues. 14 references.

  19. Ranking harbours in the Maritime provinces of Canada for potential to contaminate American lobster (Homarus americanus) with polycyclic aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Prouse, N.J. [Department of Fisheries and Oceans, Halifax, NS (Canada). Biological Sciences Branch

    1997-05-01

    The sources of polycyclic aromatic hydrocarbon (PAH) contamination within selected harbors in the Maritime provinces of Canada were evaluated by assessing point sources, population, industrial and commercial activity, international and domestic ship traffic, and the number of commercial fishing vessels. Results showed that Sydney ranked as the highest potential for PAH contamination. Ranking of the other Maritime harbors was also presented. The lobster contamination with PAHs was reviewed.

  20. Aerococcus viridans var. homari: The presence of capsule and the relationship to virulence in American lobster (Homarus americanus).

    Science.gov (United States)

    Clark, K Fraser; Wadowska, Dorota; Greenwood, Spencer J

    2016-01-01

    The relationship between virulence and encapsulation of Aerococcus viridans var. homari was evaluated by growing virulent (Rabin's) and avirulent (ATCC 10400) strains under varying culture conditions, and during challenge trials. Changes in capsule thickness were monitored using a modified lysine-ruthenium red (LRR) fixation method and transmission electron microscopy. The virulent Rabin's strain possessed a prominent capsule of 0.252 μm±0.061 μm that was diminished by in vitro growth conditions to 0.206 μm±0.076 μm. The ATCC 10400 strain capsule thickness decreased from 0.157 μm±0.043 μm to 0.117 μm±0.043 μm after 10 in vitro passages. The virulent Rabin's strain capsule was significantly thicker than the avirulent ATCC 10400 strain under all growth conditions. Rabin's strain, regardless of pre-challenge growth conditions or dose (high dose 10(7) or low dose 10(2)), was able to kill lobsters in 7 days at 15°C. ATCC 10400 strain, regardless of pre-challenge growth conditions, killed lobster only at high doses (10(7)) with varying median time to death of ∼15 days, while at low doses (10(2)) all lobsters survived and no bacteria were present after 42 days. This work demonstrates the importance of the thickness of the A. viridans capsule to virulence in the American lobster. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. SIFamide peptides in clawed lobsters and freshwater crayfish (Crustacea, Decapoda, Astacidea): a combined molecular, mass spectrometric and electrophysiological investigation.

    Science.gov (United States)

    Dickinson, Patsy S; Stemmler, Elizabeth A; Cashman, Christopher R; Brennan, Henry R; Dennison, Bobbi; Huber, Kristen E; Peguero, Braulio; Rabacal, Whitney; Goiney, Christopher C; Smith, Christine M; Towle, David W; Christie, Andrew E

    2008-04-01

    Recently, we identified the peptide VYRKPPFNGSIFamide (Val(1)-SIFamide) in the stomatogastric nervous system (STNS) of the American lobster Homarus americanus using matrix-assisted laser desorption/ionization-Fourier transform mass spectrometry (MALDI-FTMS). Given that H. americanus is the only species thus far shown to possess this peptide, and that a second SIFamide isoform, Gly(1)-SIFamide, is broadly conserved in other decapods, including another astacidean, the crayfish Procambarus clarkii, we became interested both in confirming our identification of Val(1)-SIFamide via molecular methods and in determining the extent to which this isoform is conserved within other members of the infraorder Astacidea. Here, we present the identification and characterization of an H. americanus prepro-SIFamide cDNA that encodes the Val(1) isoform. Moreover, we demonstrate via MALDI-FTMS the presence of Val(1)-SIFamide in a second Homarus species, Homarus gammarus. In contrast, only the Gly(1) isoform was detected in the other astacideans investigated, including the lobster Nephrops norvegicus, a member of the same family as Homarus, and the crayfish Cherax quadricarinatus, P. clarkii and Pacifastacus leniusculus, which represent members of each of the extant families of freshwater astacideans. These results suggest that Val(1)-SIFamide may be a genus (Homarus)-specific isoform. Interestingly, both Val(1)- and Gly(1)-SIFamide possess an internal dibasic site, Arg(3)-Lys(4), raising the possibility of the ubiquitously conserved isoform PPFNGSIFamide. However, this octapeptide was not detected via MALDI-FTMS in any of the investigated species, and when applied to the isolated STNS of H. americanus possessed little bioactivity relative to the full-length Val(1) isoform. Thus, it appears that the dodeca-variants Val(1)- and Gly(1)-SIFamide are the sole bioactive isoforms of this peptide family in clawed lobsters and freshwater crayfish.

  2. Non-amidated and amidated members of the C-type allatostatin (AST-C) family are differentially distributed in the stomatogastric nervous system of the American lobster, Homarus americanus.

    Science.gov (United States)

    Christie, Andrew E; Miller, Alexandra; Fernandez, Rebecca; Dickinson, Evyn S; Jordan, Audrey; Kohn, Jessica; Youn, Mina C; Dickinson, Patsy S

    2018-01-13

    The crustacean stomatogastric nervous system (STNS) is a well-known model for investigating neuropeptidergic control of rhythmic behavior. Among the peptides known to modulate the STNS are the C-type allatostatins (AST-Cs). In the lobster, Homarus americanus, three AST-Cs are known. Two of these, pQIRYHQCYFNPISCF (AST-C I) and GNGDGRLYWRCYFNAVSCF (AST-C III), have non-amidated C-termini, while the third, SYWKQCAFNAVSCFamide (AST-C II), is C-terminally amidated. Here, antibodies were generated against one of the non-amidated peptides (AST-C I) and against the amidated isoform (AST-C II). Specificity tests show that the AST-C I antibody cross-reacts with both AST-C I and AST-C III, but not AST-C II; the AST-C II antibody does not cross-react with either non-amidated peptide. Wholemount immunohistochemistry shows that both subclasses (non-amidated and amidated) of AST-C are distributed throughout the lobster STNS. Specifically, the antibody that cross-reacts with the two non-amidated peptides labels neuropil in the CoGs and the stomatogastric ganglion (STG), axons in the superior esophageal (son) and stomatogastric (stn) nerves, and ~ 14 somata in each commissural ganglion (CoG). The AST-C II-specific antibody labels neuropil in the CoGs, STG and at the junction of the sons and stn, axons in the sons and stn, ~ 42 somata in each CoG, and two somata in the STG. Double immunolabeling shows that, except for one soma in each CoG, the non-amidated and amidated peptides are present in distinct sets of neuronal profiles. The differential distributions of the two AST-C subclasses suggest that the two peptide groups are likely to serve different modulatory roles in the lobster STNS.

  3. Repeated sublethal exposures to the sea lice pesticide Salmosan® (azamethiphos) on adult male lobsters (Homarus americanus) causes neuromuscular dysfunction, hypoxia, metabolic disturbances and mortality.

    Science.gov (United States)

    Dounia, Daoud; Andrea, Battison; Lefort, Natalie; Van Geest, Jordana Lynne

    2016-12-01

    In Atlantic Canada and other salmon-growing regions, treatment of sea lice infestations in salmon aquaculture is necessary to protect fish health. The product Salmosan®, which contains the organophosphate azamethiphos as the active ingredient, is a pesticide presently used for treatment against sea lice. It is applied as a bath treatment and then released into the surrounding seawater. The potential for lethality to non-target species following acute and chronic exposures to Salmosan® has been studied over the past decade, however, the potential for sublethal effects on lobsters remains a concern. Adult male lobsters were exposed to 0.06, 0.5, and 5µgL -1 azamethiphos for one hour, repeated five times, over 48h. Lobsters were assessed immediately after exposure and over six days of recovery. Inhibition of muscle cholinesterase activity was detected in lobsters exposed to 0.5 and 5µgL -1 azamethiphos. The 5µgL -1 dose was considered lethal (93% cumulative mortality). Significant changes in hemolymph plasma biochemistry were most apparent in the 5µgL -1 exposure group in the immediate post-exposure samples. Citrate synthase activity was significantly lower in muscles of the 0.5µgL -1 exposure group compared to control lobsters. Mean electron transport system and standard metabolic rates tended to be lower in muscle tissue of the 0.5µgL -1 exposure group than control group lobsters. These results suggest that sublethal effects on lobster energetics may occur under laboratory exposure conditions (i.e., concentrations and duration) considered environmentally relevant, which could result in impairment under natural conditions. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Investigation and analysis of a mass mortality of commercial lobsters (Homarus americanus) in Seabrook Harbor, New Hampshire during October of 1977

    International Nuclear Information System (INIS)

    Hickey, C.R. Jr.

    1978-06-01

    During latter October 1977, a mass mortality of commercially held lobsters occurred in Seabrook Harbor, New Hampshire, at a location approximately 400-600 feet south of a construction project associated with Seabrook Station. The incident was investigated by the USNRC, with cooperative effort from other federal and several state agencies. Based upon interviews with affected lobstermen, their losses are estimated to total 2372-3440 lobsters, weighing 2965-3440 pounds, the worth between $5100-$10,320. One individual lobsterman could have incurred a loss as great as $4333. Turbidity and siltation from construction activities were alleged to have been the cause of the incident, but no direct relationship between construction and the mortality could be positively confirmed. Extreme natural environmental conditions, preceeding the mortality, combined with a confirmed presence of gaffkemia (red tail disease) in an adequately dense and confined lobster stock appear to have been responsible. The gaffkemia pathogen could have originated from any one of several possible sources, and its presence coincident with construction activities suggests a correlation between the two, but none could be proven. A delay in reporting of the incident to the USNRC, few available specimens, and a paucity of environmental data hampered the investigative efforts

  5. Role of Ih in differentiating the dynamics of the gastric and pyloric neurons in the stomatogastric ganglion of the lobster, Homarus americanus.

    Science.gov (United States)

    Zhu, Lin; Selverston, Allen I; Ayers, Joseph

    2016-06-01

    The hyperpolarization-activated inward cationic current (Ih) is known to regulate the rhythmicity, excitability, and synaptic transmission in heart cells and many types of neurons across a variety of species, including some pyloric and gastric mill neurons in the stomatogastric ganglion (STG) in Cancer borealis and Panulirus interruptus However, little is known about the role of Ih in regulating the gastric mill dynamics and its contribution to the dynamical bifurcation of the gastric mill and pyloric networks. We investigated the role of Ih in the rhythmic activity and cellular excitability of both the gastric mill neurons (medial gastric, gastric mill) and pyloric neurons (pyloric dilator, lateral pyloric) in Homarus americanus Through testing the burst period between 5 and 50 mM CsCl, and elimination of postinhibitory rebound and voltage sag, we found that 30 mM CsCl can sufficiently block Ih in both the pyloric and gastric mill neurons. Our results show that Ih maintains the excitability of both the pyloric and gastric mill neurons. However, Ih regulates slow oscillations of the pyloric and gastric mill neurons differently. Specifically, blocking Ih diminishes the difference between the pyloric and gastric mill burst periods by increasing the pyloric burst period and decreasing the gastric mill burst period. Moreover, the phase-plane analysis shows that blocking Ih causes the trajectory of slow oscillations of the gastric mill neurons to change toward the pyloric sinusoidal-like trajectories. In addition to regulating the pyloric rhythm, we found that Ih is also essential for the gastric mill rhythms and differentially regulates these two dynamics. Copyright © 2016 the American Physiological Society.

  6. Thallium, uranium, and 235U/238U ratios in the digestive gland of American lobster (Homarus americanus) from an industrialized harbor

    International Nuclear Information System (INIS)

    Chou, C.L.; Uthe, J.F.

    1995-01-01

    Only a few studies have concentrated on elements such as thallium (TI). Uranium (U) has been studied as a radionuclide of concern in food and the environment. Foodstuffs contain 10-100 ng U· -1 with vegetables and cereals contributing most heavily to the daily intake of ca 1.5 ug U. Between 10-30% of ingested U is absorbed, with most being stored in bone. Rainbow trout (onchorynchus mykiss) and longnose sucker (Catostomus catostomus) from a lake with naturally high radioactivity contained -1 in the flesh. Trout bone contained 40 ng U·g -1 . Higher tissue U concentrations occurred in fish from areas receiving U mining wastes. Bioconcentration factors for bone and flesh were estimated to be low, 118 and 14.7, respectively. This paper describes the Inductively coupled plasma-mass spectrometry (ICP-MS) determination of Tl and U in digestive gland tissue from lobsters captured in the vicinity of Belledune Harbor, New Brunswick, Canada. The harbor is the site of a lead smelter, a fertilizer plant, and a coal-fired power station (the latter due to enter production in late 1993) and thus has the potential of adding significant amounts of Tl to the local marine environment. The accumulation of Tl from water by marine shellfish is low, at least for bivalves, and the accumulated Tl is eliminated in a number of days when the animals are transferred to clean water. Bioconcentration factors for U in finfish ranged from 0.4-17 for larger species. However, because of the high concentrations of various trace elements in lobster digestive gland, its desirability as a foodstuff, and its relatively large size (approximately 20% of the edible tissue yield), we have investigated Tl and U concentrations and 235U / 238U ratios in it. 15 refs., 1 fig., 3 tabs

  7. Analysis of myofibrillar proteins and transcripts in adult skeletal muscles of the American lobster Homarus americanus: variable expression of myosins, actin and troponins in fast, slow-twitch and slow-tonic fibres.

    Science.gov (United States)

    Medler, Scott; Mykles, Donald L

    2003-10-01

    Skeletal muscles are diverse in their contractile properties, with many of these differences being directly related to the assemblages of myofibrillar isoforms characteristic of different fibers. Crustacean muscles are similar to other muscles in this respect, although the majority of information about differences in muscle organization comes from vertebrate species. In the present study, we examined the correlation between myofibrillar protein isoforms and the patterns of myofibrillar gene expression in fast, slow-phasic (S(1)) and slow-tonic (S(2)) fibers of the American lobster Homarus americanus. SDS-PAGE and western blotting were used to identify isoform assemblages of myosin heavy chain (MHC), P75, troponin T (TnT) and troponin I (TnI). RT-PCR was used to monitor expression of fast and slow (S(1)) MHC, P75 and actin in different fiber types, and the MHC and actin levels were quantified by real-time PCR. Fast and slow fibers from the claw closers predominantly expressed fast and S(1) MHC, respectively, but also lower levels of the alternate MHC. By contrast, fast fibers from the deep abdominal muscle expressed fast MHC exclusively. In addition, slow muscles expressed significantly higher levels of actin than fast fibers. A distal bundle of fibers in the cutter claw closer muscle was found to be composed of a mixture of S(1) and S(2) fibers, many of which possessed a mixture of S(1) and S(2) MHC isoforms. This pattern supports the idea that S(1) and S(2) fibers represent extremes in a continuum of slow muscle phenotype. Overall, these patterns demonstrate that crustacean skeletal muscles cannot be strictly categorized into discrete fiber types, but a muscle's properties probably represent a point on a continuum of fiber types. This trend may result from differences in innervation pattern, as each muscle is controlled by a unique combination of phasic, tonic or both phasic and tonic motor nerves. In this respect, future studies examining how muscle phenotype

  8. Lobster and cod benefit from small-scale northern marine protected areas: inference from an empirical before–after control-impact study

    Science.gov (United States)

    Moland, Even; Olsen, Esben Moland; Knutsen, Halvor; Garrigou, Pauline; Espeland, Sigurd Heiberg; Kleiven, Alf Ring; André, Carl; Knutsen, Jan Atle

    2013-01-01

    Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before–after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and partial protection to fish. By 2010, European lobster (Homarus gammarus) catch-per-unit-effort (CPUE) had increased by 245 per cent in MPAs, whereas CPUE in control areas had increased by 87 per cent. Mean size of lobsters increased by 13 per cent in MPAs, whereas increase in control areas was negligible. Furthermore, MPA-responses and population development in control areas varied significantly among regions. This illustrates the importance of a replicated BACI design for reaching robust conclusions and management decisions. Partial protection of Atlantic cod (Gadus morhua) was followed by an increase in population density and body size compared with control areas. By 2010, MPA cod were on average 5 cm longer than in any of the control areas. MPAs can be useful management tools in rebuilding and conserving portions of depleted lobster populations in northern temperate waters, and even for a mobile temperate fish species such as the Atlantic cod. PMID:23303544

  9. Field Grow-out of Juvenile American Lobsters in Long Island Sound

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Early benthic stage American lobsters, Homarus americanus, were held in a pilot nursery system in Long Island Sound (LIS) to test field grow-out, as a step toward...

  10. MANAGEMENT OF LOBSTER FISHERY WITH EAFM APPROACH IN PALABUHANRATU BAY

    Directory of Open Access Journals (Sweden)

    Katarina Hesty Rombe

    2018-06-01

    Full Text Available This research was conducted in the Palabuhanratu Bay-Sukabumi in March 2016. The purpose of this study is to diagnose the Palabuhanratu Lobster Fishery using factors of Ecosystem Approach to Fisheries Management (EAFM. Water sampling was conducted at two lobster fishing ground. Measuring and weighing morphology lobster were conducted in collectors’s house. The results of this study showed that Palabuhanratu bay water quality was still within tolerable limits for live lobster. Panulirus homarus  is the most widely lobster caught below the size of a decent catch, reaching 2528.9 Kg. CPUE of lobster was declining which indicates a decline in the stock of lobster. The income of fishermen were still very far from the average wage and stakeholder participation was still lacking in the management of the lobster fishery. Keywords: EAFM factors, lobster, palabuhanratu

  11. Optical sensor for measuring American Lobster vitality

    International Nuclear Information System (INIS)

    Tomassetti, Brian R. A.; Vetelino, John F.

    2011-01-01

    The vitality of the American Lobster (Homarus americanus) is correlated to the total hemolymph protein (THP) in lobster hemolymph (blood). The standard technique for determining lobster vitality is to draw blood from a lobster and measure THP with a refractometer. This technique is invasive and endangers the lobster's health since blood must be drawn from the lobster. In the present work an optical sensor is developed to measure a lobster's vitality in vivo. It is comprised of a broadband light source, a monochromator, a fiber optic reflection probe, a spectrometer and a computer. This sensor measures protein concentrations by exciting a lobster with 280 nm and 334 nm wavelength light sources and measuring the corresponding absorbance peaks for THP and the fluorescence peak for hemocyanin (Hc), the majority protein in hemolymph. In this work several lobsters are tested. For each lobster, absorbance and fluorescence peaks are measured using the sensor and compared to protein concentrations measured using a refractometer. It is found that the shell thickness and muscle density, which correspond directly to protein concentration and the molting stage of the lobster have a significant effect on the absorbance and fluorescence measurements. It is also found that within specific molting stages, such as pre-molt and post-molt, protein concentration measured with a refractometer correlates linearly to absorbance and fluorescence measurements with the optical sensor.

  12. Optical Sensor for Measuring American Lobster Vitality

    Science.gov (United States)

    Tomassetti, Brian R. A.; Vetelino, John F.

    2011-06-01

    The vitality of the American Lobster (Homarus americanus) is correlated to the total hemolymph protein (THP) in lobster hemolymph (blood). The standard technique for determining lobster vitality is to draw blood from a lobster and measure THP with a refractometer. This technique is invasive and endangers the lobster's health since blood must be drawn from the lobster. In the present work an optical sensor is developed to measure a lobster's vitality in vivo. It is comprised of a broadband light source, a monochromator, a fiber optic reflection probe, a spectrometer and a computer. This sensor measures protein concentrations by exciting a lobster with 280 nm and 334 nm wavelength light sources and measuring the corresponding absorbance peaks for THP and the fluorescence peak for hemocyanin (Hc), the majority protein in hemolymph. In this work several lobsters are tested. For each lobster, absorbance and fluorescence peaks are measured using the sensor and compared to protein concentrations measured using a refractometer. It is found that the shell thickness and muscle density, which correspond directly to protein concentration and the molting stage of the lobster have a significant effect on the absorbance and fluorescence measurements. It is also found that within specific molting stages, such as pre-molt and post-molt, protein concentration measured with a refractometer correlates linearly to absorbance and fluorescence measurements with the optical sensor.

  13. Keanekaragaman dan Potensi Lobster (Malacostraca: Palinuridae di Pantai Pameungpeuk, Garut Selatan, Jawa Barat

    Directory of Open Access Journals (Sweden)

    Rianta Pratiwi

    2018-01-01

    Full Text Available Coral shrimp (Panulirus spp. or known as lobster is a potential fishery commodity and economic value. The demand for domestic and export market continues to increase both as local consumption and export. Indonesia is the largest lobster fishery producer in almost all Indonesian waters, from the west coast of Sumatra to the east coast Jayapura, one of which is Pameungpeuk beach, South Garut, West Java. As a result of increasing demand, fishermen try to catch as many lobsters and the impact of lobster prices also in creases and whereas fishermen continuously take it from nature. This study was conducted to determine the diversity and potential of lobster species especially living in high wavy waters along the southern coast of Garut (Pamengpeuk, West Java.The results of observation are only three types of crayfish, namely: a. Panulirus homarus (green lobster sand; b. Panulirus longipes (lobster flower/ red lobster and Panulirus versicolor (green lobster/bamboo; is most commonly found in the area of south Garut, Pameungpeuk beach with high and strong waves. The percentage of female P longipes species (42.88% was higher compared to male P. homarus (40% and ovigerous female of P. versicolor (37.14%. While the sexual ratio between P. homarus (1:2.0:2.0; P. longipes (1:1.2:1.0 and P. versicolor: 1:1.2:1.2  which statistically showed significantly different p <0.05.

  14. POSSIBILITIES OF CULTURING BIG SEA CRABS (LOBSTERS, SPINY LOBSTERS

    Directory of Open Access Journals (Sweden)

    Ivančica Strunjak-Perović

    1999-09-01

    Full Text Available By the end of the 19 th century an experimental work on culturing big sea crabs began in Europe and North America. Great demand for their flesh as well as their high price urged many institutions to explore the possibilities of a commercial production in varios parts of the world. Lobsters (Homarus sp. were mainly used for experimenting, so that the most data available refer to them. Because of the complicated larva stage spiny lobster culturing is mainly being carried out in experimental circumstances. Despite the promissing results this aquacultural activity faces many problems (long time until they achieve a commercial size, loss of eggs due to stress sensitivity during the process of moulting, canibalism. In order to minimize these problems various researches are being carried out, like temperature influence, influence of light, way of feeding, hormonal regulation of moulting frequency. Although both lobster and spiny lobsters live in the Adriatic Sea, there are no data on their culturing in our contry. Concernig conditions in our sea there are realistic possibilities for crabs production development. In this way this delicacy would be more affordable to broader population and could be a highly rated export product.

  15. BUDIDAYA LOBSTER (Panulirus sp. DI VIETNAM DAN APLIKASINYA DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Akhmad Mustafa

    2013-12-01

    Full Text Available Desa Xuan Tun di Kecamatan Van Ninh Kota Nha Trang Provinsi Khanh Hoa merupakan lokasi pertama kegiatan budidaya lobster di Vietnam yang dilakuan pada tahun 1992. Secara umum di Kota Nha Trang, ada tiga jenis lobster yang dibudidayakan yaitu lobster mutiara (Panulirus ornatus, lobster pasir (Panulirus homarus, dan lobster batik (Panulirus longipes, karena benih lobster tersebut mudah didapat pada awalnya, cepat tumbuh, berukuran besar, warna cerah, dan memiliki harga yang tinggi. Kegiatan budidaya lobster pada dasarnya terdiri atas: penangkapan benih lobster, produksi tokolan lobster, dan pembesaran lobster yang masing-masing merupakan segmen usaha tersendiri. Pakan yang digunakan dalam produksi tokolan dan pembesaran lobster adalah berupa udang, kerang, tiram, cumi-cumi, dan ikan rucah, di mana sebagian besar dari pakan tersebut digunakan ikan rucah terutama pada pembesaran lobster. Sebagai akibat penggunaan pakan tersebut dan peningkatan jumlah keramba jaring apung yang cukup signifikan berdampak pada penurunan kualitas perairan yang memicu berkembangya penyakit susu (milky haemolymph disease sehingga terjadi penurunan produksi. Terkait dengan hasil yang didapatkan tersebut, ke depan diperlukan berbagai kegiatan termasuk untuk dapat diaplikasikan di Indonesia. Kegiatan tersebut meliputi: produksi benih lobster secara buatan di hatcheri dan penggunaan pakan buatan berupa moist pellet. Upaya pencegahan penyakit susu dan perlakuan-perlakuan praktis untuk mencegah perkembangan serangan penyakit susu juga perlu mendapat perhatian. Perkembangan budidaya lobster yang begitu cepat memicu terjadinya penurunan daya dukung lahan. Oleh karena itu, kegiatan untuk menentukan daya dukung lahan dan kesesuaian lahan menjadi penting untuk dilakukan untuk menentukan lokasi dan jumlah keramba jaring apung yang dapat dioperasikan. Penentuan daya dukung lahan dan evaluasi kesesuaian lahan tidak hanya dilakukan pada daerah yang

  16. Natural radiation dose to Gammarus

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Wrenn, M.E.; Eisenbud, M.

    1975-01-01

    The natural radiation dose rate to whole body and components of the Gammarus species (i.e., G. Tigrinus, G. Fasciatus and G. Daiberi) that occurs in the Hudson River is evaluated and the results compared with the upper limits of dose rates from man made sources to the whole body of the organisms. Methods were developed to study the distribution of alpha emitters from 226 Ra plus daughter products in Gammarus using autoradiographic techniques, taking into account the amount of radon that escapes from the organisms. This methodology may be adapted to study the distribution of alpha emitters in contaminated tissues of plants and animals

  17. Host susceptibility hypothesis for shell disease in American lobsters.

    Science.gov (United States)

    Tlusty, Michael F; Smolowitz, Roxanna M; Halvorson, Harlyn O; DeVito, Simone E

    2007-12-01

    Epizootic shell disease (ESD) in American lobsters Homarus americanus is the bacterial degradation of the carapace resulting in extensive irregular, deep erosions. The disease is having a major impact on the health and mortality of some American lobster populations, and its effects are being transferred to the economics of the fishery. While the onset and progression of ESD in American lobsters is undoubtedly multifactorial, there is little understanding of the direct causality of this disease. The host susceptibility hypothesis developed here states that although numerous environmental and pathological factors may vary around a lobster, it is eventually the lobster's internal state that is permissive to or shields it from the final onset of the diseased state. To support the host susceptibility hypothesis, we conceptualized a model of shell disease onset and severity to allow further research on shell disease to progress from a structured model. The model states that shell disease onset will occur when the net cuticle degradation (bacterial degradation, decrease of host immune response to bacteria, natural wear, and resorption) is greater than the net deposition (growth, maintenance, and inflammatory response) of the shell. Furthermore, lesion severity depends on the extent to which cuticle degradation exceeds deposition. This model is consistent with natural observations of shell disease in American lobster.

  18. Use of herring bait to farm lobsters in the Gulf of Maine.

    Science.gov (United States)

    Grabowski, Jonathan H; Clesceri, Erika J; Baukus, Adam J; Gaudette, Julien; Weber, Matthew; Yund, Philip O

    2010-04-15

    Ecologists, fisheries scientists, and coastal managers have all called for an ecosystem approach to fisheries management, yet many species such as the American lobster (Homarus americanus) are still largely managed individually. One hypothesis that has yet to be tested suggests that human augmentation of lobster diets via the use of Atlantic herring (Clupea harengus) as bait may contribute to recent increases in lobster landings. Currently 70% of Atlantic herring landings in the Gulf of Maine are used as bait to catch lobsters in traps throughout coastal New England. We examined the effects of this herring bait on the diet composition and growth rate of lobsters at heavily baited vs. seasonally closed (i.e., bait free) sites in coastal Maine. Our results suggest that human use of herring bait may be subsidizing juvenile lobster diets, thereby enhancing lobster growth and the overall economic value and yield of one of the most valuable fisheries in the U.S. Our study illustrates that shifting to an ecosystem approach to fisheries management should require consideration of cross-fishery interactions.

  19. Use of herring bait to farm lobsters in the Gulf of Maine.

    Directory of Open Access Journals (Sweden)

    Jonathan H Grabowski

    2010-04-01

    Full Text Available Ecologists, fisheries scientists, and coastal managers have all called for an ecosystem approach to fisheries management, yet many species such as the American lobster (Homarus americanus are still largely managed individually. One hypothesis that has yet to be tested suggests that human augmentation of lobster diets via the use of Atlantic herring (Clupea harengus as bait may contribute to recent increases in lobster landings. Currently 70% of Atlantic herring landings in the Gulf of Maine are used as bait to catch lobsters in traps throughout coastal New England.We examined the effects of this herring bait on the diet composition and growth rate of lobsters at heavily baited vs. seasonally closed (i.e., bait free sites in coastal Maine. Our results suggest that human use of herring bait may be subsidizing juvenile lobster diets, thereby enhancing lobster growth and the overall economic value and yield of one of the most valuable fisheries in the U.S.Our study illustrates that shifting to an ecosystem approach to fisheries management should require consideration of cross-fishery interactions.

  20. Lobster Logbook Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The NWHI lobster trap fishery, which commenced in the mid-1970s, is a multispecies fishery and primarily targets the Hawaiian spiny lobster (Panuliris marginatus)...

  1. Gammarus-Microbial Interactions: A Review

    Directory of Open Access Journals (Sweden)

    Daniel Nelson

    2011-01-01

    Full Text Available Gammarus spp. are typically classified as shredders under the functional feeding group classification. In the wild and in the laboratory, Gammarus spp. will often shred leaves, breaking them down into finer organic matter fractions. However, leaf litter is a poor quality food source (i.e., high C : N and C : P ratios and very little leaf material is assimilated by shredders. In freshwater habitats leaf litter is colonized rapidly (within ∼1-2 weeks by aquatic fungi and bacteria, making the leaves more palatable and nutritious to consumers. Several studies have shown that Gammarus spp. show preference for conditioned leaves over nonconditioned leaves and certain fungal species to others. Furthermore, Gammarus spp. show increased survival and growth rates when fed conditioned leaves compared to non-conditioned leaves. Thus, Gammarus spp. appear to rely on the microbial biofilm associated with leaf detritus as a source of carbon and/or essential nutrients. Also, Gammarus spp. can have both positive and negative effects on the microbial communities on which they fed, making them an important component of the microbial loop in aquatic ecosystems.

  2. Simulation experiments on the migration of Gammarus zaddachi and Gammarus chevreuxi

    NARCIS (Netherlands)

    Girisch, H.B.; Dennert, H.G.

    1975-01-01

    The migratory activity of Gammarus zaddachi and Gammarus chevreuxi is investigated in a current chamber, in which a tidal cycle can be simulated. In fresh running water the number of animals drifting with the current is of about the same magnitude as the number of animals actively swimming against

  3. ASPEK REPRODUKSI LOBSTER (Panulirus sp. DI PERAIRAN TELUK EKAS PULAU LOMBOK

    Directory of Open Access Journals (Sweden)

    M Junaidi

    2010-04-01

    Full Text Available Purposes of this research are to know some reproduction aspects of lobster, including sex ratio, gonad maturity level, size of first gonad mature, fekundity, and relationship of length-weight some. This research was conducted in June until November 2009 in Ekas Bay. During research 5 lobsters species were obtained, they are Panulirus homarus, P. versicolor, P. ornatus P. penicillatus and P. longiceps, with their of is well-balanced (1:1. Size of first gonad mature of P. homarus at carapace length 77,44 mm that happened during June - November with fekundity 28.000 - 96.000 granule, P. versicolor at carapace length 82,20 mm that happened during June - September with fekundity 16.500 - 71.000 granule, P. ornatus at carapace length 76,74 mm that happened during September - November with fekundity 47.000 - 87.000 granule, P. penicillatus at carapace length 69,84 mm that happened during June - November with fekundity 31.000 - 150.000 granule and P. longiceps at carapace length 68,47 mm that happened in June - August with fekundity 47.000 - 140.000 granule. Relationship of carapace length and body weight of five species, also male and female was described using linier regression equation and have negative allometrict pattern, where accretion of carapace length was quicker than body weight accretion.Keyword : reproduction aspect, lobster, Ekas Bay

  4. Culture-independent analysis of bacterial communities in hemolymph of American lobsters with epizootic shell disease.

    Science.gov (United States)

    Quinn, Robert A; Smolowitz, Roxanna; Chistoserdov, Andrei Y

    2013-03-26

    Epizootic shell disease (ESD) of the American lobster Homarus americanus H. Milne Edwards, 1837 is a disease of the carapace that presents grossly as large, melanized, irregularly shaped lesions, making the lobsters virtually unmarketable because of their grotesque appearance. We analyzed the bacterial communities present in the hemolymph of lobsters with and without ESD using nested-PCR of the 16S rRNA genes followed by denaturing gradient gel electrophoresis. All lobsters tested (n = 42) had bacterial communities in their hemolymph, and the community profiles were highly similar regardless of the sampling location or disease state. A number of bacteria were detected in a high proportion of samples and from numerous locations, including a Sediminibacterium sp. closely related to a symbiont of Tetraponera ants (38/42) and a Ralstonia sp. (27/42). Other bacteria commonly encountered included various Bacteroidetes, Pelomonas aquatica, and a Novosphingobium sp. One bacterium, a different Sediminibacterium sp., was detected in 20% of diseased animals (n = 29), but not in the lobsters without signs of ESD (n = 13). The bacteria in hemolymph were not the same as those known to be present in lesion communities except for the detection of a Thalassobius sp. in 1 individual. This work demonstrates that hemolymph bacteremia and the particular bacterial species present do not correlate with the incidence of ESD, providing further evidence that microbiologically, ESD is a strictly cuticular disease. Furthermore, the high incidence of the same species of bacteria in hemolymph of lobsters may indicate that they have a positive role in lobster fitness, rather than in disease, and further investigation of the role of bacteria in lobster hemolymph is required.

  5. The Lobster Mission

    Science.gov (United States)

    Barthelmy, Scott

    2011-01-01

    I will give an overview of the Goddard Lobster mission: the science goals, the two instruments, the overall instruments designs, with particular attention to the wide-field x-ray instrument (WFI) using the lobster-eye-like micro-channel optics.

  6. Lesion bacterial communities in American lobsters with diet-induced shell disease.

    Science.gov (United States)

    Quinn, Robert A; Metzler, Anita; Tlusty, Michael; Smolowitz, Roxanna M; Leberg, Paul; Chistoserdov, Andrei Y

    2012-04-26

    In southern New England, USA, shell disease affects the profitability of the American lobster Homarus americanus fishery. In laboratory trials using juvenile lobsters, exclusive feeding of herring Clupea harengus induces shell disease typified initially by small melanized spots that progress into distinct lesions. Amongst a cohabitated, but segregated, cohort of 11 juvenile lobsters fed exclusively herring, bacterial communities colonizing spots and lesions were investigated by denaturing gradient gel electrophoresis of 16S rDNA amplified using 1 group-specific and 2 universal primer sets. The Bacteroidetes and Proteobacteria predominated in both spots and lesions and included members of the orders Flavobacteriales (Bacteriodetes), Rhodobacterales, Rhodospirillales and Rhizobiales (Alphaproteobacteria), Xanthomonadales (Gammaproteobacteria) and unclassified Gammaproteobacteria. Bacterial communities in spot lesions displayed more diversity than communities with larger (older) lesions, indicating that the lesion communities stabilize over time. At least 8 bacterial types persisted as lesions developed from spots. Aquimarina 'homaria', a species commonly cultured from lesions present on wild lobsters with epizootic shell disease, was found ubiquitously in spots and lesions, as was the 'Candidatus Kopriimonas aquarianus', implicating putative roles of these species in diet-induced shell disease of captive lobsters.

  7. MOLECULAR DETECTION AND CLONING FOR RICKETTSIA-LIKE BACTERIA OF MILKY HAEMOLYMPH DISEASE OF SPINY LOBSTER Panulirus spp.

    Directory of Open Access Journals (Sweden)

    Isti Koesharyani

    2017-01-01

    Full Text Available Spiny lobster (Panulirus homarus and Panulirus ornatus are important commodities for Indonesia. The aquaculture of lobster is susceptible for several diseases like parasite, fungi, bacteria, and virus. Among those diseases, milky haemolymph disease (MHD is often seen as a symptom to mass mortality occurred at lobster farms in Gerupuk Bay of Lombok. The purpose of this study was to determine the lobster diseases on cage culture in Gerupuk Bay of Lombok, West Nusa Tenggara. The study was undertaken from January to March 2015. Diseases status was determined by application of molecular plat-form, polymerase chain reaction (PCR with designation of specific primer for MHD (254F/R, 254F: 5’-CGA-GGA-CCA-GAG-ATG-GAC-CTT-3’ and 254R: 5’-GCT-CAT-TGT-CAC-CGC-CAT-TGT-3’ with PCR size product of 254 bp. and for cloned the pathogen was used TA-cloning Invitrogen for the DNA plasmid as positive control for other analysis. Several tissue samples i.e hepatopancreas, haemolymph, part of muscle hepatopancreas P. homarus and P. ornatus were taken from cage culture farms at Gerupuk Bay then preserved on 90% ethanol for further analysis by PCR and then the amplificated DNA were cloned into pCR®2.1 plasmid and transformed into competent E. coli. The result showed that almost all lobster samples from Gerupuk Bay were positive infected by MHD, as the results of PCR amplification whereas the band appeared at 254bp. Also MHD plasmid has been successfully cloned and will be used for further examination. Histopathologically in hepatopancreas infection have seen necrosis that contain numerous of rickettsia-like bacteria.

  8. Creation of a gilded trap by the high economic value of the Maine lobster fishery.

    Science.gov (United States)

    Steneck, R S; Hughes, T P; Cinner, J E; Adger, W N; Arnold, S N; Berkes, F; Boudreau, S A; Brown, K; Folke, C; Gunderson, L; Olsson, P; Scheffer, M; Stephenson, E; Walker, B; Wilson, J; Worm, B

    2011-10-01

    Unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. This lack of diversity may increase risks of ecological and economic disruptions. Centuries of intense fishing have extirpated most apex predators in the Gulf of Maine (United States and Canada), effectively creating an American lobster (Homarus americanus) monoculture. Over the past 20 years, the economic diversity of marine resources harvested in Maine has declined by almost 70%. Today, over 80% of the value of Maine's fish and seafood landings is from highly abundant lobsters. Inflation-corrected income from lobsters in Maine has steadily increased by nearly 400% since 1985. Fisheries managers, policy makers, and fishers view this as a success. However, such lucrative monocultures increase the social and ecological consequences of future declines in lobsters. In southern New England, disease and stresses related to increases in ocean temperature resulted in more than a 70% decline in lobster abundance, prompting managers to propose closing that fishery. A similar collapse in Maine could fundamentally disrupt the social and economic foundation of its coast. We suggest the current success of Maine's lobster fishery is a gilded trap. Gilded traps are a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences. Large financial gain creates a strong reinforcing feedback that deepens the trap. Avoiding or escaping gilded traps requires managing for increased biological and economic diversity. This is difficult to do prior to a crisis while financial incentives for maintaining the status quo are large. The long-term challenge is to shift fisheries management away from single species toward integrated social-ecological approaches that diversify local ecosystems, societies, and economies. ©2011 Society for Conservation

  9. Sex Diversity Approach of Spiny Lobster (Panulirus spp) to Marine Oil Spill Pollution in Southern Waters of Java

    Science.gov (United States)

    Haryono, F. E. D.; Ambariyanto; Sulistyo, I.

    2018-02-01

    Coastal of southern Java waters is known as inhabit area of spiny lobster. Accumulation of hydrocarbon frequently occurs at the coastal waters as impact of oil pollution caused by oil leak from supplying ship of crude oil to Cilacap refinery. As shipping channel of oil, presence of oil spills is often detected at coastal areas of Cilacap. It can be indicated by range of sediment in the area which has risk levels in range of low to medium-low. It was, therefore, found that some locations suffered a greater impact on the ecological which giving high risk for marine organism life. Spiny lobster is one of many organism living at sea bed which threatened its life due to the presence of oil. Population of Spiny Lobster has to be protected because it has commercially valuable commodity for producing high nutrition. Considering the matters, it is therefore important to find a method for alleviating the problem. Investigation should be focused on biological aspect of spiny lobster in encountering extreme pollution at the coastal. For that purpose, a field research was conducted from January until July 2015. Using gillnet with 1 inch mesh size, the lobsters were randomly collected from southern Java districts waters. There were 1137 lobsters collected from six districts waters. Furthermore, the sample was morphologically identified and it was found that there were six species in the areas. In all area, P. homarus was found as dominant species, except in Gunung kidul district which was dominated by P. penicillatus. In term of sex diversity, there is statistically difference in number of female and male, each species no significant. Even though environment quality was very worse, there was found existence of ovigerous female in the research area as about 12% of the population. Those facts strongly indicated that the lobsters has a unique adaptation to survive in extremely low quality of environment due to marine oil spill.

  10. Implications of Future Northwest Atlantic Bottom Temperatures on the American Lobster (Homarus americanus) Fishery

    Science.gov (United States)

    Rheuban, Jennie E.; Kavanaugh, Maria T.; Doney, Scott C.

    2017-12-01

    Sea surface temperatures of the northwest Atlantic have warmed dramatically over the last several decades, while benthic temperatures have increased at a slower pace. Here we analyze a subset of the CMIP5 global Earth system model ensemble using a statistical downscaling approach to determine potential future changes in benthic temperatures on the northwest Atlantic continental shelf and slope (business-as-usual (RCP8.5) and a climate-policy (RCP4.5) scenario are projected to increase by 0-1.5°C and 1.2-2.4°C by 2050 and 0-1.9°C and 2.3-4.3°C by the end of the century for RCP4.5 and RCP8.5, respectively. H. americanus experiences thermal stress at temperatures above 20°C, and projected increases in temperature is likely to result in changes in the distribution of optimal thermal egg hatching and settlement indicators. Inshore regions of southern New England, where H. americanus biomass and catch have been declining historically, will likely become inhospitable under either future scenario, while thermal egg hatching and settlement indicators will expand offshore and in the Gulf of Maine. These changes imply that members of the fishery based in southern New England may need to recapitalize to larger vessels to prepare for potential changes brought on by future climate warming. Results from the downscaling presented here can be useful in preparing for potential changes to other fisheries or in future climate vulnerability analyses.

  11. Polarographic studies on the nature of cadmium in scallop, oyster, and lobster

    Energy Technology Data Exchange (ETDEWEB)

    Chou, C L; Uthe, J F; Zook, E G

    1978-04-01

    Free and bound forms of cadmium were determined in raw shellfish by use of differential pulse polarography and atomic absorption spectrophotometry. Free cadmium is defined by its polarographic peak potential of -0.62 +- 0.02 V (saturated calomel electrode) in solvent washed ammonium sulfate extracts. Bound cadmium was determined by subtracting the free cadmium from the total cadmium present in the meat. Both scallop (various species) and American lobster (Homarus americanus) muscle tissues contain no free cadmium. Oyster (various species), on the other hand, had a considerable percentage (approximately 50%) of its total cadmium present as free cadmium, a phenomena as yet unexplained. The detection limit for free cadmium is approximately 0.05 ..mu..g/g raw tissue.

  12. Coupling Recruitment Forecasts with Economics in the Gulf of Maine's American Lobster Fishery

    Science.gov (United States)

    Wahle, R.; Oppenheim, N.; Brady, D. C.; Dayton, A.; Sun, C. H. J.

    2016-02-01

    Accurate predictions of fishery recruitment and landings represent an important goal of fisheries science and management, but linking environmental drivers of fish population dynamics to financial markets remains a challenge. A fundamental step in that process is understanding the environmental drivers of fishery recruitment. American lobster (Homarus americanus) populations of the northwest Atlantic have been undergoing a dramatic surge, mostly driven by increases the Gulf of Maine. Settler-recruit models that track cohorts after larvae settle to the sea bed are proving useful in predicting subsequent fishery recruitment some 5-7 years later. Here we describe new recruitment forecasting models for the lobster fishery at 11 management areas from Southern New England to Atlantic Canada. We use an annual survey of juvenile year-class strength and environmental indicators to parameterize growth and mortality terms in the model. As a consequence of a recent widespread multi-year downturn in larval settlement, our models suggest that the peak in lobster abundance in the Gulf of Maine will be passed in the near future. We also present initial steps in the coupling of forecast data with economic models for the fishery. We anticipate that these models will give stakeholders and policy makers time to consider their management choices for this most valuable of the region's fisheries. Our vision is to couple our forecast model outputs to an economic model that captures the dynamics of market forces in the New England and Canadian Maritime lobster fisheries. It will then be possible to estimate the financial status of the fishery several years in advance. This early warning system could mitigate the adverse effects of a fluctuating fishery on the coastal communities that are perilously dependent upon it.

  13. Lobster trap detection at the Saba Bank

    NARCIS (Netherlands)

    Beek, van I.J.M.

    2012-01-01

    According to previous studies and anecdotal evidence there are a lot of lost lobster traps at the Saba Bank. One study estimated the loss to be between 210 and 795 lobster traps per year. The Saba Bank is an approximately 2,200 km2 submerged area and spiny lobster (Panulirus argus) is one of the

  14. Natural radiation dose to Gammarus from Hudson river

    International Nuclear Information System (INIS)

    Paschoa, A.S.; Wrenn, M.E.; Eisenbud, M.

    1979-01-01

    The purpose of this investigation is to evaluate the natural radiation dose rate to whole body and components of the Gammarus species, a zooplankton which occurs in the Hudson River among other places, and to compare the results with the upper limits of dose rates from man-made sources. The alpha dose rates to the exoskeleton and soft tissues are about 10 times the average alpha dose rate to the whole body, assuming uniform distribution of 226 Ra. The natural alpha radiation dose rate to Gammarus represents only about 5% of the total natural dose to the organism, i.e., 492 mrad/yr. The external dose rate due to 40 K, 238 U plus daughters and 232 Th plus daughters accumulated in the sediments comprise 91% of that total natural dose rate, the remaining percentage being due to natural internal beta emitters and cosmic radiation. Man-made sources can cause an external dose rate up to 224 mrad/yr, which comprises roughly 1/3 of the total dose rate (up to 716 mrad/yr; natural plus man-made) to the Gammarus of Hudson River in front of Indian Point Nuclear Power Station. However, in terms of dose-equivalent the natural sources of radiation would contribute more than 75% of the total dose to Gammarus

  15. Effects of Prior Experience on Shelter-Seeking Behavior of Juvenile American Lobsters.

    Science.gov (United States)

    Bayer, Skylar R; Bianchi, Katherine M; Atema, Jelle; Jacobs, Molly W

    2017-04-01

    Shelter-seeking behaviors are vital for survival for a range of juvenile benthic organisms. These behaviors may be innate or they may be affected by prior experience. After hatching, American lobsters Homarus americanus likely first come into contact with shelter during the late postlarval (decapodid) stage, known as stage IV. After the subsequent molt to the first juvenile stage (stage V), they are entirely benthic and are thought to be highly cryptic. We hypothesized that postlarval (stage IV) experience with shelter would carry over into the first juvenile stage (stage V) and reduce the time needed for juveniles to locate and enter shelters (sheltering). We found some evidence of a carryover effect, but not the one we predicted: stage V juveniles with postlarval shelter experience took significantly longer to initiate sheltering. We also hypothesized that stage V juveniles would demonstrate learning by relocating shelters more quickly with immediate prior experience. Our findings were mixed. In a maze, juveniles with immediate prior experience were faster to regain visual contact with shelter, suggesting that they had learned the location of the shelter. In contrast, there was no significant effect of immediate prior experience on time to initiate sheltering in an open arena, or in the maze after juveniles had regained visual contact. We conclude that very young (stage V) juvenile lobsters modify their shelter-seeking behavior based on prior experiences across several timescales. Ecologically relevant variation in habitat exposure among postlarval and early juvenile lobsters may influence successful recruitment in this culturally and commercially important fishery species.

  16. EVALUATION OF FISHING LOBSTERS PALINURUS ELEPHAS (FABRICIUS, 1787 BY LOBSTER TRAPS IN THE MIDDLE ADRIATIC SEA

    Directory of Open Access Journals (Sweden)

    Perica Cetinić

    1997-04-01

    Full Text Available The work contains the results of fishing lobsters Palinurus elephas by lobsters traps from Komiža, island Vis with one eye side size of 60 mm as well as the evaluation of its effect to their population. The correct size of her eye was evaluated by the analysis of representation of immature lobsters in the catchs of the lobsters traps. 171 examples of lobsters were analyzed (116 males and 55 females with their lengths ranging from 22 to 45 cm. Total of 53 units (31% were less than 28 mm and at that length lobsters are barred from catch and transport. Such a length has been regulated by the valid Regulation on protection of fish and other sea organisms. Therefore, the lobster trap from Komiža, island Vis was evaluated as having the negative impact on the lobsters population.

  17. HOW MANY LOBSTERS ARE IN THE SEA?

    Directory of Open Access Journals (Sweden)

    Ernest Enns

    2011-05-01

    Full Text Available A lobster fishery must have a reasonable estimate of the number of lobsters within the fishery in order to regulate the annual harvest. Stereological sampling procedures are used to estimate the number of lobsters in a defined region of the sea. From a given point in the fishery, a selective sample in a random direction to the boundary of the fishery is taken. This is repeated to generate a systematic sample from which the total population is estimated.

  18. Characterization of Key Aroma Compounds in Raw and Thermally Processed Prawns and Thermally Processed Lobsters by Application of Aroma Extract Dilution Analysis.

    Science.gov (United States)

    Mall, Veronika; Schieberle, Peter

    2016-08-24

    Application of aroma extract dilution analysis (AEDA) to an aroma distillate of blanched prawn meat (Litopenaeus vannamei) (BPM) revealed 40 odorants in the flavor dilution (FD) factor range from 4 to 1024. The highest FD factors were assigned to 2-acetyl-1-pyrroline, 3-(methylthio)propanal, (Z)-1,5-octadien-3-one, trans-4,5-epoxy-(E)-2-decenal, (E)-3-heptenoic acid, and 2-aminoacetophenone. To understand the influence of different processing conditions on odorant formation, fried prawn meat was investigated by means of AEDA in the same way, revealing 31 odorants with FD factors between 4 and 2048. Also, the highest FD factors were determined for 2-acetyl-1-pyrroline, 3-(methylthio)propanal, and (Z)-1,5-octadien-3-one, followed by 4-hydroxy-2,5-dimethyl-3(2H)-furanone, (E)-3-heptenoic acid, and 2-aminoacetophenone. As a source of the typical marine, sea breeze-like odor attribute of the seafood, 2,4,6-tribromoanisole was identified in raw prawn meat as one of the contributors. Additionally, the aroma of blanched prawn meat was compared to that of blanched Norway and American lobster meat, respectively (Nephrops norvegicus and Homarus americanus). Identification experiments revealed the same set of odorants, however, with differing FD factors. In particular, 3-hydroxy-4,5-dimethyl-2(5H)-furanone was found as the key aroma compound in blanched Norway lobster, whereas American lobster contained 3-methylindole with a high FD factor.

  19. 50 CFR 697.18 - Lobster management areas.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Lobster management areas. 697.18 Section... Measures § 697.18 Lobster management areas. The following lobster management areas are established for... American lobster EEZ management areas is available upon request to the Office of the Regional Administrator...

  20. 50 CFR 300.132 - Lobster harvest limitations.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Lobster harvest limitations. 300.132... FISHERIES REGULATIONS Vessels of the United States Fishing in Colombian Treaty Waters § 300.132 Lobster harvest limitations. (a) Berried lobsters. A berried (egg-bearing) lobster in treaty waters may not be...

  1. Diseases of spiny lobsters: a review.

    Science.gov (United States)

    Shields, J D

    2011-01-01

    Spiny lobsters have few reported pathogens, parasites and symbionts. However, they do have a diverse fauna comprised of a pathogenic virus, several bacteria, protozoans, helminths and even symbiotic crustaceans. A few idiopathic syndromes have also been reported, but these appear correlated with lobsters held in poor conditions. Fungal and bacterial pathogens present significant threats for rearing spiny lobsters in aquaculture settings, but only one pathogen, Panulirus argus virus 1, is thought to have damaged a fishery for a spiny lobster. No doubt others will emerge as lobsters are brought into aquaculture setting and as fishing pressure intensifies with stocks become more susceptible to anthropogenic stressors. Copyright © 2010 Elsevier Inc. All rights reserved.

  2. PENDEKATAN SOSIAL-EKOLOGI UNTUK PENILAIAN KESESUAIAN LOKASI RESTOCKING LOBSTER PASIR Panulirus homarus (Linnaeus, 1758 PADA BEBERAPA PERAIRAN DI INDONESIA

    Directory of Open Access Journals (Sweden)

    Amula Nurfiarini

    2016-11-01

    yang sama. Jika dibandingkan dengan kriteria pengambilan keputusan terhadap tingkat kesesuaian habitat, menunjukkan sebanyak 17 lokasi berada pada kategori kelayakan tinggi, dan 11 lokasi kategori kelayakan sedang. Prioritas lokasi restocking, terpilih tiga lokasi dengan nilai kelayakan tertinggi yakni perairan Batu Karas dan Pananjung Barat (Pangandaran, serta Perairan Karang Asem (Trenggalek.

  3. Pola Kemitraan Pemasaran Lobster di Kota Bengkulu

    OpenAIRE

    Romdhon, M. Mustopa; sukiyono, ketut

    2011-01-01

    Relationship among lobster marketing agents could determine partnership pattern, but how the relationship was build and run, its need depth explanation. The research was aims to synthesize partnership pattern, rights and obligations among agents under lobster marketing at Bengkulu Municipal. The Partnership pattern was explained descriptively through non-contractual, equipment and capital achieved. The research was employed at North Bengkulu Districts at three villages (Pasar Pedati, Pasar Ke...

  4. Lobster-eye infrared focusing optics

    Science.gov (United States)

    Grubsky, Victor; Gertsenshteyn, Michael; Jannson, Tomasz

    2006-08-01

    We propose a new imaging device for the long infrared spectral range, inspired by the natural eye of a lobster. Such a lobster-eye lens is composed of reflecting channels with a square cross section capable of wide angle of view and practically omni-directional imaging. As in large-aperture lenses, aberrations can significantly degrade the image. We show two methods of reducing aberrations: by selecting proper material for the mirrors and by making channels with absorbing sections.

  5. Four new Gammarus species from Tibetan Plateau with a key to Tibetan freshwater gammarids (Crustacea, Amphipoda, Gammaridae

    Directory of Open Access Journals (Sweden)

    Zhonge Hou

    2018-03-01

    Full Text Available Four new species of the genus Gammarus are described and illustrated from Tibetan Plateau. Gammarus altus sp. n. and G. limosus sp. n. are characterized by pereopods III–IV with a few short setae and uropod III with marginal spines accompanied by short setae. Gammarus kangdingensis sp. n. and G. gonggaensis sp. n. are characterized by pereopods III–IV with long straight setae on posterior margins and inner ramus of uropod III 0.4 times as long as outer ramus. Detailed morphological comparisons with related species are discussed. A key to 15 Gammarus species from the Tibetan Plateau and a map of their distributions are provided.

  6. Transcriptome of the freshwater amphipod Gammarus pulex hepatopancreas

    Directory of Open Access Journals (Sweden)

    E. Gismondi

    2016-06-01

    Full Text Available So far, ecotoxicological studies used biomarkers of exposure or of effects in order to investigate the impacts of contaminated areas on biota (Peakall, 1994 [6]. However, although these results are important in the ecotoxicological risk assessment, biomarkers are very specific and only provide information on the biological processes or physiological pathways targeted by the biomarkers experimenters choose to test (Monsinjon and Knigge, 2007 [5]. In recent years, proteomics have become a major tool in ecotoxicology, as they provide a global insight into the mechanism of action of pollutants without the need of hypothesis testing or any preconception on the biological processes likely impacted (Gismondi et al., 2015; Trapp et al., 2015 [7]; Truebano, 2016 [8]. However, the analysis of proteomic results is often limited due to the lack of database, especially for non-model organisms, such as Gammarus sp, commonly used as biological model in ecotoxicology (Sornom et al., 2012 [11]; Vellinger et al., 2013 [9]; Gismondi and Thomé, 2014 [1]; Lebrun et al., 2014 [3]. Here, we performed Illumina HiSeq sequencing to total RNA isolated from the hepatopancreas (i.e. detoxification tissue of Gammarus pulex males and females coming from uncontaminated river and contaminated river (e.g. PCB, benzo(apyrene. Approximately 290 M paired-end reads were assembled, filtered and sorted into 39,801 contigs whose 10.878 were similar of proteins available in databases. The assembled contigs could represent a reference hepatopancreas transcriptome for G. pulex, and constitute an important resource for future investigations on the impacts of pollutants on invertebrate biota, since it would improve the understanding of the mechanisms of action involved in toxicity. In addition, the hepatopancreas transcriptome will also allow the identification of new potential biomarkers for the ecotoxicological risk assessments. Assembled contigs were deposited in the European

  7. Gammarus orinos n. sp. from the Massif Central (France): its genetic and morphological distinction from Gammarus ibericus Margalef, 1951 (Crustacea, Amphipoda)

    NARCIS (Netherlands)

    Pinkster, Sjouk; Scholl, Adolf

    1984-01-01

    Until 1974 Gammarus ibericus was known only from the type-locality in Spain. In that year, Goedmakers recorded the species from many localities in the Massif Central, France. Indeed, these populations show a great morphological resemblance to the Spanish ones. These French populations were used in

  8. DIMENSI METRIK GRAPH LOBSTER Ln (q;r

    Directory of Open Access Journals (Sweden)

    PANDE GDE DONY GUMILAR

    2013-05-01

    Full Text Available The metric dimension of connected graph G is the cardinality of minimum resolving set in graph G. In this research, we study how to find the metric dimension of lobster graph Ln (q;r. Lobster graph Ln (q;r is a regular lobster graph with vertices backbone on the main path, every backbone vertex is connected to q hand vertices and every hand vertex is connected to r finger vertices, with n, q, r element of N. We obtain the metric dimension of lobster graph L2 (1;1 is 1, the metric dimension of lobster graph L2 (1;1 for n > 2 is 2.

  9. LOBSTER - New Space X-Ray telescopes

    International Nuclear Information System (INIS)

    Hudec, R.; Pina, L.; Simon, V.; Sveda, L.; Inneman, A.; Semencova, V.; Skulinova, M.

    2007-01-01

    We discuss the technological and scientific aspects of fully innovative very wide-field X-ray telescopes with high sensitivity. The prototypes of Lobster telescopes designed, developed and tested are very promising, allowing the proposals for space projects with very wide-field Lobster Eye X-ray optics to be considered for the first time. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study of various astrophysical objects such as AGN, SNe, Gamma-ray bursts (GRBs), X-ray flashes (XRFs), galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc. For example, the Lobster optics based X-ray All Sky Monitor is capable to detect around 20 GRBs and 8 XRFs yearly and this will surely significantly contribute to the related science

  10. 76 FR 71501 - Atlantic Coastal Fisheries Cooperative Management Act Provisions; American Lobster Fishery

    Science.gov (United States)

    2011-11-18

    ... Lobster Fishery AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric... American lobster regulations that would limit entry into the lobster trap fishery in Lobster Conservation... to fish in Area 1 with up to 800 lobster traps. The proposed limited entry program responds to the...

  11. LOBSTER: new space x-ray telescopes

    Science.gov (United States)

    Hudec, R.; Sveda, L.; Pína, L.; Inneman, A.; Semencova, V.; Skulinova, M.

    2017-11-01

    The LOBSTER telescopes are based on the optical arrangement of the lobster eye. The main difference from classical X-ray space telescopes in wide use is the very large field of view while the use of optics results in higher efficiency if compared with detectors without optics. Recent innovative technologies have enabled to design, to develop and to test first prototypes. They will provide deep sensitive survey of the sky in X-rays for the first time which is essential for both long-term monitoring of celestial high-energy sources as well as in understanding transient phenomena. The technology is now ready for applications in space.

  12. Ecology: avoidance of disease by social lobsters.

    Science.gov (United States)

    Behringer, Donald C; Butler, Mark J; Shields, Jeffrey D

    2006-05-25

    Transmissible pathogens are the bane of social animals, so they have evolved behaviours to decrease the probability of infection. There is no record, however, of social animals avoiding diseased individuals of their own species in the wild. Here we show how healthy, normally gregarious Caribbean spiny lobsters (Panulirus argus) avoid conspecifics that are infected with a lethal virus. Early detection and avoidance of infected, though not yet infectious, individuals by healthy lobsters confers a selective advantage and highlights the importance of host behaviour in disease transmission among natural populations.

  13. The Case of Lobster Shell Disease

    Science.gov (United States)

    Hollen, Shawna; Toney, Jaime L.; Bisaccio, Daniel; Haberstroh, Karen Marie; Herbert, Timothy

    2011-01-01

    The authors combined content-driven and inquiry-based lessons into the framework of problem-based learning (PBL). They did this in eight third- through sixth-grade classrooms--two each from grades 3-5, one from sixth grade, and one mixed-grade special education. These older elementary students explored a local problem of lobsters infected by…

  14. Exploiting volatile opportunistic computing resources with Lobster

    Science.gov (United States)

    Woodard, Anna; Wolf, Matthias; Mueller, Charles; Tovar, Ben; Donnelly, Patrick; Hurtado Anampa, Kenyi; Brenner, Paul; Lannon, Kevin; Hildreth, Mike; Thain, Douglas

    2015-12-01

    Analysis of high energy physics experiments using the Compact Muon Solenoid (CMS) at the Large Hadron Collider (LHC) can be limited by availability of computing resources. As a joint effort involving computer scientists and CMS physicists at Notre Dame, we have developed an opportunistic workflow management tool, Lobster, to harvest available cycles from university campus computing pools. Lobster consists of a management server, file server, and worker processes which can be submitted to any available computing resource without requiring root access. Lobster makes use of the Work Queue system to perform task management, while the CMS specific software environment is provided via CVMFS and Parrot. Data is handled via Chirp and Hadoop for local data storage and XrootD for access to the CMS wide-area data federation. An extensive set of monitoring and diagnostic tools have been developed to facilitate system optimisation. We have tested Lobster using the 20 000-core cluster at Notre Dame, achieving approximately 8-10k tasks running simultaneously, sustaining approximately 9 Gbit/s of input data and 340 Mbit/s of output data.

  15. Modeling the dispersal of spiny lobster (

    NARCIS (Netherlands)

    Whomersley, P.; van der Molen, J.; Holt, D.; Trundle, C.; Clark, S.; Fletcher, D.

    2018-01-01

    Knowledge of larval dispersal, population dynamics and connectivity in relation to the management and conservation of commercially important species is vital if existing fisheries are to remain sustainable into the future. Larval dispersal of the commercially exploited spiny lobster, Palinurus

  16. 75 FR 1597 - Western Pacific Crustacean Fisheries; 2010 Northwestern Hawaiian Islands Lobster Harvest Guideline

    Science.gov (United States)

    2010-01-12

    ... Pacific Crustacean Fisheries; 2010 Northwestern Hawaiian Islands Lobster Harvest Guideline AGENCY.... ACTION: Notification of lobster harvest guideline. SUMMARY: NMFS announces that the annual harvest guideline for the commercial lobster fishery in the Northwestern Hawaiian Islands (NWHI) for calendar year...

  17. Les Amphipodes du genre Gammarus dans le Bassin d’Arcachon

    NARCIS (Netherlands)

    Labourg, P.J.; Pinkster, S.; Stock, J.H.

    1971-01-01

    Five species of the genus Gammarus have been found in and around the Basin of Arcachon (southwestern France). Short notes on the autecology of these species are given. Literature records of G. duebeni and of G. aequicauda from the Basin rest on confusion with other species, as is proved by

  18. Changes in ventilation and locomotion of Gammarus pulex (Crustacea, Amphipoda) in response to low concentrations of pharmaceuticals

    NARCIS (Netherlands)

    Lange, de H.J.; Peeters, E.T.H.M.; Lürling, M.F.L.L.W.

    2009-01-01

    Exposure to contaminants below lethal concentrations may affect the performance of organisms, resulting in measurable differences in behavior. We measured the response of the benthic invertebrate Gammarus pulex (Crustacea, Amphipoda) to sublethal concentrations of three pharmaceuticals, fluoxetine,

  19. 50 CFR 640.27 - Spiny lobster import prohibitions.

    Science.gov (United States)

    2010-10-01

    ... ATLANTIC Management Measures § 640.27 Spiny lobster import prohibitions. (a) Minimum size limits for... than Puerto Rico or the U.S. Virgin Islands, and a more restrictive minimum size limit that applies to Puerto Rico and the U.S. Virgin Islands. (1) No person may import a spiny lobster with less than a 5...

  20. 50 CFR 622.50 - Caribbean spiny lobster import prohibitions.

    Science.gov (United States)

    2010-10-01

    ... ATLANTIC Management Measures § 622.50 Caribbean spiny lobster import prohibitions. (a) Minimum size limits... States other than Puerto Rico or the U.S. Virgin Islands, and a more restrictive minimum size limit that applies to Puerto Rico and the U.S. Virgin Islands. (1) No person may import a Caribbean spiny lobster...

  1. Effekte von Xenohormonen auf die limnischen Invertebraten Gammarus fossarum (Crustacea, Amphipoda) und Marisa cornuarietis (Mollusca, Prosobranchia)

    OpenAIRE

    Schirling, Martin

    2005-01-01

    In dieser Arbeit werden Effekte von Xenohormonen auf Gammarus fossarum und Marisa cornuarietis anhand verschiedener Parameter, auf unterschiedlichen biologischen Ebenen dargestellt. In einem Laborexperiment mit G. fossarum, das Grundlage für weitere Untersuchungen im Rahmen dieser Arbeit war, konnte gezeigt werden, dass sich die Stressproteine hsp90 und hsp70 im Laufe der Oocytenreifung gegenläufig verhalten. Sowohl in einem Freilandversuch, bei dem der Einfluss von Kläranlageneinleitern ...

  2. Hidden diversity and host specificity in cycliophorans; a phylogeographic analysis along the North Atlantic and Mediterranean Sea

    DEFF Research Database (Denmark)

    Obst, Matthias; Funch, Peter; Gonzalo, Giribet

    2005-01-01

    In order to elucidate the evolutionary history and the population structure of the membersof the phylum Cycliophora, which live commensally on three species of lobsters, we studiedsequence variation in the mitochondrial gene cyctochromecoxidase subunit I. Overall 242sequences from 16 locations.......0504). However, itwas low for commensals onNephrops norvegicus(6 haplotypes,h= 0.3899, ππ= 0.0035), andintermediate for cycliophorans onHomarus gammarus(5 haplotypes,h= 0.3020, ππ= 0.0140).Although two of the host lobsters co-inhabit the coastal waters of Europe, a strong geneticstructure (78.45% of the observed...... genetic variation) was detected among populations on allhost species, indicating the existence of a reproductively isolated species on each lobster.In addition, genetic structure over long distances exists among populations on each hostspecies. Such patterns can be explained by the limited dispersal...

  3. Red Tide Strands South African Rock Lobsters

    Science.gov (United States)

    2002-01-01

    Although some red tides form a healthy part of phytoplankton production, recurrent harmful or toxic blooms also occur, with results depending upon the type of plankton and on atmospheric and oceanic conditions. At Elands Bay in South Africa's Western Cape province, about 1000 tons of rock lobsters beached themselves during February 2002, when the decay of dense blooms of phytoplankton caused a rapid reduction in the oxygen concentration of nearshore waters. The lobsters (or crayfish, as they are known locally) moved toward the breaking surf in search of oxygen, but were stranded by the retreating tide. The Multi-angle Imaging SpectroRadiometer's nadir camera acquired these red, green, blue composites on February 2 and 18, 2002, during Terra orbits 11315 and 11548. The colors have been accentuated to highlight the bloom, and land and water have been enhanced separately. The two views show the shoreward migration of the algal bloom. Each image represents an area of about 205 kilometers x 330 kilometers. Elands Bay is situated near the mouth of the Doring River, about 75 kilometers northeast of the jutting Cape Columbine. The term 'red tide' is used to refer to a number of different types of phytoplankton blooms of various hues. The wine color of certain parts of this bloom are consistent with the ciliate species Mesodinium rubrum, which has been associated with recurring harmful algal blooms along the Western Cape coast. Under these conditions, the lobsters are not poisoned. During the recent event, government and military staff transported as many of the living lobsters as possible to areas that were less affected by the red tide. At the same time, people came from across South Africa to gather the undersized creatures for food. The effects of the losses on the maritime economy are expected to be felt over the next few years. MISR was built and is managed by NASA's Jet Propulsion Laboratory, Pasadena, CA, for NASA's Office of Earth Science, Washington, DC. The Terra

  4. Behavioral Immunity Suppresses an Epizootic in Caribbean Spiny Lobsters.

    Science.gov (United States)

    Butler, Mark J; Behringer, Donald C; Dolan, Thomas W; Moss, Jessica; Shields, Jeffrey D

    2015-01-01

    Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of "behavioral immunity"; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics) practiced by Caribbean spiny lobsters (Panulirus argus) when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We capitalized on a "natural experiment" in which a die-off of sponges in the Florida Keys (USA) resulted in a loss of shelters for juvenile lobsters over a ~2500km2 region. Lobsters were thus concentrated in the few remaining shelters, presumably increasing their exposure to the contagious virus. Despite this spatial reorganization of the population, viral prevalence in lobsters remained unchanged after the sponge die-off and for years thereafter. A field experiment in which we introduced either a healthy or PaV1-infected lobster into lobster aggregations in natural dens confirmed that spiny lobsters practice behavioral immunity. Healthy lobsters vacated dens occupied by PaV1-infected lobsters despite the scarcity of alternative shelters and the higher risk of predation they faced when searching for a new den. Simulations from a spatially-explicit, individual-based model confirmed our empirical results, demonstrating the efficacy of behavioral immunity in preventing epizootics in this system.

  5. Behavioral Immunity Suppresses an Epizootic in Caribbean Spiny Lobsters.

    Directory of Open Access Journals (Sweden)

    Mark J Butler

    Full Text Available Sociality has evolved in a wide range of animal taxa but infectious diseases spread rapidly in populations of aggregated individuals, potentially negating the advantages of their social interactions. To disengage from the coevolutionary struggle with pathogens, some hosts have evolved various forms of "behavioral immunity"; yet, the effectiveness of such behaviors in controlling epizootics in the wild is untested. Here we show how one form of behavioral immunity (i.e., the aversion of diseased conspecifics practiced by Caribbean spiny lobsters (Panulirus argus when subject to the socially transmitted PaV1 virus, appears to have prevented an epizootic over a large seascape. We capitalized on a "natural experiment" in which a die-off of sponges in the Florida Keys (USA resulted in a loss of shelters for juvenile lobsters over a ~2500km2 region. Lobsters were thus concentrated in the few remaining shelters, presumably increasing their exposure to the contagious virus. Despite this spatial reorganization of the population, viral prevalence in lobsters remained unchanged after the sponge die-off and for years thereafter. A field experiment in which we introduced either a healthy or PaV1-infected lobster into lobster aggregations in natural dens confirmed that spiny lobsters practice behavioral immunity. Healthy lobsters vacated dens occupied by PaV1-infected lobsters despite the scarcity of alternative shelters and the higher risk of predation they faced when searching for a new den. Simulations from a spatially-explicit, individual-based model confirmed our empirical results, demonstrating the efficacy of behavioral immunity in preventing epizootics in this system.

  6. The Gammarus pulex-group in Italy (Crustacea, Amphipoda) (A study based on material from the Museo Civico di Storia Naturale, Verona)

    NARCIS (Netherlands)

    Goedmakers, Annemarie; Pinkster, Sjouk

    1977-01-01

    A historical review is given of the literature oil Italian members of the genus Gammarus. Only three Gammarus species were known with certainty from Italy, viz G. fossarum Koch, 1836, G. lacustris G.O. Sars, 1863, and G. cf. balcanicus Schäferna, 1922. G. fossarum is widely distributed in the

  7. Members of the Gammarus pulex-group (Crustacea – Amphipoda) from North Africa and Spain, with description of a new species from Morocco

    NARCIS (Netherlands)

    Pinkster, Sjouk

    1971-01-01

    Gammarus gauthieri (Karaman) was known from North Africa only. During systematic sampling, carried out in 1969 to 1970, it became clear, that the species is also widely distributed in the Iberian peninsula. Comparative descriptions of this species and of two other members of the Gammarus

  8. Studies on the diet of various lobster species have shown ...

    African Journals Online (AJOL)

    spamer

    However, the proportion of the population feeding showed marked seasonal trends at both sites, tracking the commercial ..... The general diet of crustaceans, molluscs and echino- .... habits of polychelid lobsters in the Western Mediterranean.

  9. True navigation and magnetic maps in spiny lobsters.

    Science.gov (United States)

    Boles, Larry C; Lohmann, Kenneth J

    2003-01-02

    Animals are capable of true navigation if, after displacement to a location where they have never been, they can determine their position relative to a goal without relying on familiar surroundings, cues that emanate from the destination, or information collected during the outward journey. So far, only a few animals, all vertebrates, have been shown to possess true navigation. Those few invertebrates that have been carefully studied return to target areas using path integration, landmark recognition, compass orientation and other mechanisms that cannot compensate for displacements into unfamiliar territory. Here we report, however, that the spiny lobster Panulirus argus oriented reliably towards a capture site when displaced 12-37 km to unfamiliar locations, even when deprived of all known orientation cues en route. Little is known about how lobsters and other animals determine position during true navigation. To test the hypothesis that lobsters derive positional information from the Earth's magnetic field, lobsters were exposed to fields replicating those that exist at specific locations in their environment. Lobsters tested in a field north of the capture site oriented themselves southwards, whereas those tested in a field south of the capture site oriented themselves northwards. These results imply that true navigation in spiny lobsters, and perhaps in other animals, is based on a magnetic map sense.

  10. Radioactive lobsters put squeeze on Sellafield

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1996-11-01

    British Nuclear Fuels is facing a new controversy over its Sellafield Works in Cumbria. Levels of the radioactive isotope technetium-99 in lobsters close to the works have risen 40-fold since 1993 -and now far exceed EC standards for contamination of food after a nuclear accident. Radioactive doses to local seafood consumers have been rising steeply since BNFL commissioned a new enhanced actinide removal plant (EARP) in 1994. The Environment Agency has now asked BNFL to consider ways of reducing technetium-99 discharges from the plant - but the company is also under pressure to maintain throughput to meet the safety concerns of the Nuclear Installations Inspectorate (NII) and avoid disrupting the reprocessing of spent Magnox reactor fuel. (UK).

  11. Radioactive lobsters put squeeze on Sellafield

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    British Nuclear Fuels is facing a new controversy over its Sellafield Works in Cumbria. Levels of the radioactive isotope technetium-99 in lobsters close to the works have risen 40-fold since 1993 -and now far exceed EC standards for contamination of food after a nuclear accident. Radioactive doses to local seafood consumers have been rising steeply since BNFL commissioned a new enhanced actinide removal plant (EARP) in 1994. The Environment Agency has now asked BNFL to consider ways of reducing technetium-99 discharges from the plant - but the company is also under pressure to maintain throughput to meet the safety concerns of the Nuclear Installations Inspectorate (NII) and avoid disrupting the reprocessing of spent Magnox reactor fuel. (UK)

  12. Effects of molting and environmental factors on trace metal body-burdens and hemocyanin concentrations in the American lobster, Homarus americanus.

    NARCIS (Netherlands)

    Engel, D.W.; Brouwer, M.H.J.; Mercaldo-Allen, R.

    2001-01-01

    Hemocyanin concentrations in the hemolymph of marine crustacea are dependent on the molt cycle and on environmental conditions. Studies in our laboratories have found that hemocyanin levels in blue crabs are reduced after ecdysis and under conditions of environmental stress (Engel, Brouwer, &

  13. Characteristics of fatty acid composition of Gammarus lacustris inhabiting lakes with and without fish.

    Science.gov (United States)

    Makhutova, O N; Sharapova, T A; Kalachova, G S; Shulepina, S P; Gladyshev, M I

    2016-01-01

    The effect of a biotic factor--the presence of predatory fish in water--on the composition and content of fatty acids in crustaceans was studied in the populations of the lake amphipod Gammarus lacustris from two lakes with fish and three lakes without fish. It was found that, at an overall increase in the quantity and quality of food resources (namely, increase in the content of eicosapentaenoic acid and docosahexaenoic acid (DHA) in the biomass), the relative rate of DHA accumulation in gammarids in the lakes without fish is higher than in the lake with fish.

  14. Chronotoxicity of contaminants (etanol and hezvy metales) in a freshwater teleost Dario rerio (Hamilton, 1882) and marine amphipods Gammarus aequicauda (Martynov, 1931) and Gammarus chevreuxi (Sexton, 1913) = Cronotixicidad de contaminantes (etanol y metales pesados) en el teleósteo de agua dulce Dario rerio (Hamilton, 1822) y los antípodos marinos, Gammarus aequicauda (Martynov, 1931) y Gammarus chevreuxi (Sexton, 1913)

    OpenAIRE

    Bello Marín, Carolina

    2015-01-01

    Esta tesis tiene como objetivo investigar los efectos del etanol y metales pesados (cadmio y mercurio) en los patrones diarios de dos especies acuáticas clave: pez cebra (Darío rerio) y anfípodo gammarus (G. aequicauda y G. chevreuxi). La investigación se realizó en dos niveles organizativos: comportamental y molecular. Con este fin, hemos establecido cuatro objetivos específicos: 1. Investigar los efectos al etanol en el pez cebra en función en su ritmo circadiano. 2. Determinar la exi...

  15. Disease effects on lobster fisheries, ecology, and culture: overview of DAO Special 6.

    Science.gov (United States)

    Behringer, Donald C; Butler, Mark J; Stentiford, Grant D

    2012-08-27

    Lobsters are prized by commercial and recreational fishermen worldwide, and their populations are therefore buffeted by fishery practices. But lobsters also remain integral members of their benthic communities where predator-prey relationships, competitive interactions, and host-pathogen dynamics push and pull at their population dynamics. Although lobsters have few reported pathogens and parasites relative to other decapod crustaceans, the rise of diseases with consequences for lobster fisheries and aquaculture has spotlighted the importance of disease for lobster biology, population dynamics and ecology. Researchers, managers, and fishers thus increasingly recognize the need to understand lobster pathogens and parasites so they can be managed proactively and their impacts minimized where possible. At the 2011 International Conference and Workshop on Lobster Biology and Management a special session on lobster diseases was convened and this special issue of Diseases of Aquatic Organisms highlights those proceedings with a suite of articles focused on diseases discussed during that session.

  16. 76 FR 77214 - Hawaii Crustacean Fisheries; 2012 Northwestern Hawaiian Islands Lobster Harvest Guideline

    Science.gov (United States)

    2011-12-12

    ... Crustacean Fisheries; 2012 Northwestern Hawaiian Islands Lobster Harvest Guideline AGENCY: National Marine...: Notification of lobster harvest guideline. SUMMARY: NMFS establishes the annual harvest guideline for the commercial lobster fishery in the Northwestern Hawaiian Islands (NWHI) for calendar year 2012 at zero...

  17. 50 CFR 665.249 - Lobster size and condition restrictions in Permit Area 2.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Lobster size and condition restrictions in... WESTERN PACIFIC Hawaii Fisheries § 665.249 Lobster size and condition restrictions in Permit Area 2. (a) Only spiny lobsters with a carapace length of 8.26 cm or greater may be retained (see Figure 1 to this...

  18. Animal behavior frozen in time: gregarious behavior of Early Jurassic lobsters within an ammonoid body chamber.

    Science.gov (United States)

    Klompmaker, Adiël A; Fraaije, René H B

    2012-01-01

    Direct animal behavior can be inferred from the fossil record only in exceptional circumstances. The exceptional mode of preservation of ammonoid shells in the Posidonia Shale (Lower Jurassic, lower Toarcian) of Dotternhausen in southern Germany, with only the organic periostracum preserved, provides an excellent opportunity to observe the contents of the ammonoid body chamber because this periostracum is translucent. Here, we report upon three delicate lobsters preserved within a compressed ammonoid specimen of Harpoceras falciferum. We attempt to explain this gregarious behavior. The three lobsters were studied using standard microscopy under low angle light. The lobsters belong to the extinct family of the Eryonidae; further identification was not possible. The organic material of the three small lobsters is preserved more than halfway into the ammonoid body chamber. The lobsters are closely spaced and are positioned with their tails oriented toward each other. The specimens are interpreted to represent corpses rather than molts. The lobsters probably sought shelter in preparation for molting or against predators such as fish that were present in Dotternhausen. Alternatively, the soft tissue of the ammonoid may have been a source of food that attracted the lobsters, or it may have served as a long-term residency for the lobsters (inquilinism). The lobsters represent the oldest known example of gregariousness amongst lobsters and decapods in the fossil record. Gregarious behavior in lobsters, also known for extant lobsters, thus developed earlier in earth's history than previously known. Moreover, this is one of the oldest known examples of decapod crustaceans preserved within cephalopod shells.

  19. 50 CFR 697.24 - Exempted waters for Maine State American lobster permits.

    Science.gov (United States)

    2010-10-01

    ... lobster permits. 697.24 Section 697.24 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT... lobster permits. A person or vessel holding a valid permit or license issued by the State of Maine that lawfully permits that person to engage in commercial fishing for American lobster may, with the approval of...

  20. Effects of two PBDE congeners on the moulting enzymes of the freshwater amphipod Gammarus pulex

    International Nuclear Information System (INIS)

    Gismondi, Eric; Thomé, Jean-Pierre

    2014-01-01

    Polybrominated diphenyl ethers (PBDEs) are abundant in aquatic environment. However, only few studies have investigated their impacts on freshwater invertebrates. This work aimed to study the effects of BDE-47 and BDE-99 congeners on the chitobiase and chitinolytic enzymes activities of the freshwater amphipod Gammarus pulex, according to gender, PBDE concentration and time of exposure. In addition, the bioaccumulation of BDE-47 and BDE-99 were measured. Results revealed that females have bioaccumulated more PBDE than males, and BDE-99 was more accumulated than BDE-47. PBDE exposures for 96 h have caused chitobiase and chitinolytic enzymes inhibition. This study not only indicate the importance of taking into account various confounding factors (gender, congeners, concentration) to understand PBDE effects, but underline also disruptions of molting enzymes activities. These disturbances suggest effects on the gammarid development and reproduction, and consequently effects on the gammarid population, and on a larger scale, a dysfunction of the ecosystem. - Highlights: • G. pulex females bioaccumulate more PBDE than males. • PBDE exposure increases enzyme activities involved in moult process. • Gammarid gender, PBDE congener and concentration are confounding factors. - BDE-47 and BDE-99 are accumulated in Gammarus pulex males and females and have impacted the moulting process, since they influenced the moult enzymes activities

  1. Revisiting Maine’s lobster commons: rescaling political subjects

    Directory of Open Access Journals (Sweden)

    Jennifer F. Brewer

    2012-08-01

    Full Text Available Calls for cross-scalar theoretical and methodological approaches are not new to commons scholarship. Such efforts might be hastened by channelling poststructuralist and critical theory perspectives through the geographic subfield of political ecology, including attention to political scales and subjects. Toward this end, this paper reconsiders Maine’s lobster fishery. This case has provided rich material for watershed commons scholarship, demonstrating the ability of social groups to conserve resources independent of government or markets, and it continues to offer new findings. Recent fieldwork shows that as lobster boat captains advance collective interests through state-supported co-management governance arrangements, concerns of crew and non-fishing community members may be marginalized. Regulatory exclusion prevents broader distribution of resource benefits at a time when employment alternatives are scarce. More pluralistic approaches to commons theory and its policy application have utility well beyond the lobster case.

  2. Systematics and position of Nephrops among the lobsters.

    Science.gov (United States)

    Tshudy, Dale

    2013-01-01

    This chapter presents and explains the position of Nephrops norvegicus in the classification of lobsters. Covered, in order, are systematic classification of Nephrops, taxonomic history of Nephrops, and analysis of Nephrops in nephropid phylogeny. The genus Nephrops was erected by Leach in 1814 and has a long and interesting taxonomic history. Prior to 1972, Nephrops was known by 14 Recent species. All but one of these, N. norvegicus, were removed to a new genus, Metanephrops, by Jenkins (1972). Today, N. norvegicus is still the only known living representative of the genus. Similarly, Nephrops is known by only one fossil species, the Miocene Nephrops kvistgaardae, although several other fossil species have been previously referred to this genus. Nephrops, along with the other familiar and commercially important marine clawed lobsters, is referred to Family Nephropidae, one of 17 marine clawed lobster families arrayed in 3 infraorders, 6 families each in the Astacidea and Glypheidea and 5 in the Polychelida. Infraorder Astacidea includes the Superfamily Nephropoidea, as well as the lesser known 'reef lobsters' of the Superfamily Enoplometopoidea, and the freshwater crayfish, Superfamily Astacoidea. In phylogenetic analyses, the freshwater crayfish form a sister group to the Nephropoidea. It is interpreted that freshwater crayfish evolved from nephropoid lobsters, but from which lobster group is uncertain. The taxonomic placement of N. norvegicus is stable at all levels, from species on up. Despite that, the phylogenetic relationships of Nephrops to other nephropid genera are unsettled due to conflicting results in morphological and molecular analyses. Currently, new morphological characters and new genes are being analysed in the hope of elucidating nephropid phylogeny. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Predation Risk within Fishing Gear and Implications for South Australian Rock Lobster Fisheries

    Science.gov (United States)

    Briceño, Felipe; Linnane, Adrian Joseph; Quiroz, Juan Carlos; Gardner, Caleb; Pecl, Gretta Tatyana

    2015-01-01

    Depredation of southern rock lobster (Jasus edwardsii) within fishing gear by the Maori octopus (Pinnoctopus cordiformis) has economic and ecological impacts on valuable fisheries in South Australia. In addition, depredation rates can be highly variable resulting in uncertainties for the fishery. We examined how in-pot lobster predation was influenced by factors such as lobster size and sex, season, fishing zone, and catch rate. Using mixed modelling techniques, we found that in-pot predation risk increased with lobster size and was higher for male lobsters. In addition, the effect of catch rate of lobsters on predation risk by octopus differed among fishing zones. There was both a seasonal and a spatial component to octopus predation, with an increased risk within discrete fishing grounds in South Australia at certain times of the year. Information about predation within lobster gear can assist fishery management decision-making, potentially leading to significant reduction in economic losses to the fishery. PMID:26489035

  4. Predation Risk within Fishing Gear and Implications for South Australian Rock Lobster Fisheries.

    Directory of Open Access Journals (Sweden)

    Felipe Briceño

    Full Text Available Depredation of southern rock lobster (Jasus edwardsii within fishing gear by the Maori octopus (Pinnoctopus cordiformis has economic and ecological impacts on valuable fisheries in South Australia. In addition, depredation rates can be highly variable resulting in uncertainties for the fishery. We examined how in-pot lobster predation was influenced by factors such as lobster size and sex, season, fishing zone, and catch rate. Using mixed modelling techniques, we found that in-pot predation risk increased with lobster size and was higher for male lobsters. In addition, the effect of catch rate of lobsters on predation risk by octopus differed among fishing zones. There was both a seasonal and a spatial component to octopus predation, with an increased risk within discrete fishing grounds in South Australia at certain times of the year. Information about predation within lobster gear can assist fishery management decision-making, potentially leading to significant reduction in economic losses to the fishery.

  5. Spiny lobster Panulirus versicolor filogenetic and genetic in Lombok waters, West Nusa Tenggara, Indonesia

    Directory of Open Access Journals (Sweden)

    Pranata B.

    2018-02-01

    Full Text Available This study aims to identify the phylogenetic spiny lobster Panulirus versicolor in Lombok waters, Indonesia and its association with P. versicolor spiny lobster from several regions of the Indian Ocean based on the cytochrome oxidase I (COI gene. The researchers collected tissue samples from 13 P. versicolor spiny lobster in Lombok waters. 9 haplotypes were identified with haplotype diversity values (Hd and nucleotides (Pi respectively Hd = 0.859 and Pi = 0.00509. Research results exhibit P. versicolor spiny lobster population from the waters of Lombok is closely related to the spiny lobster population in some regions of the Indian Ocean. In general, P. versicolor spiny lobster population formed a monophyletic clone with spiny lobsters from several regions of the Indian Ocean with genetic distance values (P-distance from 0.001 to 0.004. The reconstruction of the haplotype network exhibited no genetic structure, which means that each population is not genetically isolated from others.

  6. On the origin and variation of colors in lobster carapace

    OpenAIRE

    Begum, Shamima; Cianci, Michele; Durbeej, Bo; Falklöf, Olle; Haedener, Alfons; Helliwell, John R.; Helliwell, Madeleine; Regan, Andrew C.; Watt, Ian F.

    2015-01-01

    The chemical basis of the blue-black to pink-orange color change on cooking of lobster, due to thermal denaturation of an astaxanthin-protein complex, alpha-crustacyanin, in the lobster carapace, has so far been elusive. Here, we investigate the relaxation of the astaxanthin pigment from its bound enolate form to its neutral hydroxyketone form, as origin of the spectral shift, by analyzing the response of UV-vis spectra of a water-soluble 3-hydroxy-4-oxo-beta-ionone model of astaxanthin to in...

  7. First endemic freshwater Gammarus from Crete and its evolutionary history-an integrative taxonomy approach.

    Science.gov (United States)

    Hupało, Kamil; Mamos, Tomasz; Wrzesińska, Weronika; Grabowski, Michał

    2018-01-01

    The Mediterranean islands are known as natural laboratories of evolution with a high level of endemic biodiversity. However, most biodiversity assessments have focused mainly on terrestrial and marine fauna, leaving the freshwater animals aside. Crete is one of the largest islands in the Mediterranean Basin, with a long history of isolation from the continental mainland. Gammarid amphipods are often dominant in macrozoobenthic communities in European inland waters. They are widely used in biomonitoring and exotoxicological studies. Herein, we describe Gammarus plaitisi sp. nov., endemic to Cretan streams, based on morphological characters and a set of molecular species delimitation methods using mitochondrial cytochrome oxidase subunit I and 16S rRNA genes as well as nuclear 28S rDNA, ITS1 and EF1-alpha genes. The divergence of the new species is strongly connected with the geological history of the island supporting its continental origin.

  8. Variation in sensitivity to metals in Gammarus pulex and Asellus aquaticus

    Energy Technology Data Exchange (ETDEWEB)

    Roberts, D.A. [Univ. of Sheffield (United Kingdom)

    1994-12-31

    The aim of this study was to investigate inter- and intra-specific variation in two ecologically important freshwater organisms; Asellus aquaticus and Gammarus pulex. Animals of each species were collected from contaminated and uncontaminated sites. The toxicity of zinc and cadmium to these populations was determined using acute toxicity tests. Results show that G. pulex was more sensitive to the toxicants than A. aquaticus. For both species, animals from contaminated sites were less sensitive than animals from uncontaminated sites. The mechanistic bases of this observed variation was investigated. Experiments were performed to determine the accumulation, detoxification and distribution of zinc and cadmium in animals from contaminated and uncontaminated populations. Differences in metal accumulation and production of metal binding proteins have been found and the implication of these will be discussed.

  9. Dietary Preference of Gammarus pulex and Asellus aquaticus during a Laboratory Breeding Programme for Ecotoxicological Studies

    Directory of Open Access Journals (Sweden)

    M. C. Bloor

    2011-01-01

    Full Text Available An investigation was undertaken to establish if Gammarus pulex and Asellus aquaticus preferred a diet of unconditioned, artificially or naturally conditioned alder leaves (Alnus glutinosa. Standardised, 24 hour ex situ feeding assays were undertaken with both species to determine their food preference. The results showed that A. aquaticus ate more leaf material compared to G. pulex (Z 23.909, P 0.001 when exposed to all three test variables. Also, both G. pulex and A. aquaticus demonstrated a preference for naturally conditioned leaves compared to the other two variables, with unconditioned leaves proving the least popular food option for both macroinvertebrates (Z 18.803, <0.001. However, both species ate varying amounts of all the leaf treatments (Z 136.399, <0.001. Subsequently, the author outlined a feeding methodology for natural alder leaf conditioning that could be used during a laboratory breeding programme.

  10. Historical commercial West Coast rock lobster Jasus lalandii ...

    African Journals Online (AJOL)

    Historic data from 1891 to 2001 on the annual exports of rock lobster Jasus lalandii products (canned, frozen tails, raw whole frozen, cooked whole frozen and live) from the South African west coast are used to estimate the annual commercial landings by this fishery. Conversion factors were developed to convert canned, ...

  11. Distribution of slipper lobsters (Decapoda: Scyllaridae in Uruguayan waters

    Directory of Open Access Journals (Sweden)

    Fabrizio Scarabino

    2017-09-01

    Full Text Available Abstract Scyllarid lobsters are commonly found in tropical waters with scarce records from temperate zones in the southwestern Atlantic. Here, we provide new information about the distribution of Scyllarides deceptor Holthuis, 1963 along the Uruguayan continental shelf and include a new austral record for Scyllarus depressus (Smith, 1881.

  12. From Lobster Shells to Plastic Objects: A Bioplastics Activity

    Science.gov (United States)

    Hudson, Reuben; Glaisher, Samuel; Bishop, Alexandra; Katz, Jeffrey L.

    2015-01-01

    A multiple day activity for students to create large-scale plastic objects from the biopolymer chitin (major component of lobster, crab, and shrimp shells) is described. The plastic objects created are durable and made from benign materials, making them suitable for students to take home to play with. Since the student-created plastic objects are…

  13. Detection of Panulirus argus Virus 1 in Caribbean spiny lobsters.

    Science.gov (United States)

    Montgomery-Fullerton, Megan M; Cooper, Roland A; Kauffman, Kathryn M; Shields, Jeffrey D; Ratzlaff, Robert E

    2007-06-07

    Panulirus argus Virus 1 (PaV1) is a pathogenic virus that infects Caribbean spiny lobsters P. argus in the Florida Keys. We have developed a PCR detection assay for PaV1 for the purpose of studying the natural history of the virus and for monitoring the prevalence of infection. The detection of the virus in hemolymph and other tissues is based on the PCR amplification of a 499 bp product using specific primers designed from a cloned fragment of the PaV1 genome. The sensitivity limit for the assay was 1.2 fg of purified viral DNA. The PaV1 primers did not react with lobster DNA, oyster DNA, Ostreid Herpesvirus 1, or murine cytomegalovirus. Using this assay, we successfully followed the course of infection in lobsters inoculated with PaV1 and we detected infections in wild-caught lobsters from the Florida Keys. We have also established guidelines for interpreting infection results from the PCR assay for PaV1.

  14. The Lobster Tale: An Exercise in Critical Thinking

    Science.gov (United States)

    Stepanovich, Paul L.

    2009-01-01

    Professors in management and business are encouraged to incorporate critical thinking as an objective in their courses. "The Lobster Tale" provides an opportunity to engage students in various levels of critical thinking, ranging from a relatively superficial reading to an examination of the deeper, often hidden issues. Using the foundations of…

  15. Reproductive biology of spiny lobster Panulirus regius from the ...

    African Journals Online (AJOL)

    Reproductive biology of spiny lobster Panulirus regius from the northwestern Cape Verde Islands. R Freitas, A Medina, S Correira, M Castro. Abstract. No Abstract. African Journal of Marine Science Vol.29(2) 2007: pp. 201-208. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL ...

  16. Predation by West Coast rock lobsters (Jasus lalandit) on two ...

    African Journals Online (AJOL)

    opened black mussel to ensure that they were feeding. Each rock lobster was then starved for a further 24h to ensure equal starvation levels and complete clearance of the digestive tract. (Zoutendyk 1988). before each of the following experiments was performed. For all experiments described below, winkle measurements ...

  17. Aspects of Automation in a Lobster Farming Plant

    Directory of Open Access Journals (Sweden)

    Steinar Grimsen

    1987-01-01

    Full Text Available This paper describes the automation aspects of rearing juvenile lobsters for sea ranching. It gives an outline of rearing techniques and presents specifications for a feeding system. A description is given of the equipment that has been developed. Other automation and instrumentation tasks are briefly discussed.

  18. Parasites of crayfish ( P. clarki ) and lobsters ( Macrobrachium ...

    African Journals Online (AJOL)

    Studies on parasites of crayfish and lobsters as indicators of metal pollution in Great Kwa River, Nigeria was evaluated using appropriate instruments for determination of Physicochemical parameters and detection of metals. Formol ether centrifugation method was used for isolation of parasites. A total of 150 crayfish and ...

  19. Pengambilan Keputusan Waktu Panen Pada Usaha Pembesaran Lobster di Pulau Lombok Provinsi NTB

    Directory of Open Access Journals (Sweden)

    Deden Kurniawan

    2017-08-01

    Full Text Available Lobsters represent as a valuable commodity to be determined by their length and weight. In Indonesia, the minimum legal size of lobster is 7cm of carapace length and 200 grams of weight, and this is stipulated on regulation of Ministry of Marine Affairs and Fisheries No.1/2015. Instead of behaving in accordance with the rule, farmers still harvest lobsters as soon as they are of marketable size to reduce the risk of mortality and to generate income instantly. This paper develops a structural equation model partially least square (SEM PLS to analyze decision making process to harvest lobster in Indonesia. The study established by structural equation modeling partially least square shows that the decision making to harvest lobster is driven by patron-client relationship, time constraint, and working complexity.Keywords: lobster growing activities, decision to harvest, Lombok, SEM PLSABSTRAKLobster sebagai komoditas yang berharga ditentukan oleh ukuran panjang dan berat. Di Indonesia, berdasarkan Peraturan Menteri Kelautan dan Perikanan No.1 / 2015, ukuran minimal lobster adalah memiliki panjang karapas 7cm dan berat 200 gram. Pelaku usaha pembesaran lobster justru tidak mentaati aturan yang ada, ukuran lobster yang dipanen justru ditentukan oleh permintaan pasar yang dilakukan untuk mengurangi risiko kematian lobster dan mempercepat waktu dalam memperoleh penghsilan. Penelitian ini dilakukan untuk melakukan analisis keputusan waktu panen lobster di Indonesia. Metode yang digunakan adalah model persamaan struktural sebagian least square (SEM PLS. Hasil studi menunjukkan bahwa keputusan untuk memanen lobster ditentukan oleh hubungan patron dengan klien, keterbatasan waktu, dan kompleksitas pekerjaan.Kata kunci: kegiatan pembesaran lobster, keputusan waktu panen, Lombok, SEM PLS

  20. Distribution and ecology of gammarus lacustris G. O. Sars in Norway, with notes on its morphology and biology

    Energy Technology Data Exchange (ETDEWEB)

    Oekland, K A

    1969-01-01

    The distribution of Gammarus lacustris in Norway is found to be affected mainly by hydrographical and geological factors. Of special interest is the species absence in the more acid lakes. In some areas, inefficiencies in dispersal and predation by fish also influence the distribution patterns. A tendency for the larger animals to occur in lakes rich in lime is demonstrated. Morphology, breeding biology, depth distribution, and parasites are also treated.

  1. Animal behavior frozen in time: gregarious behavior of Early Jurassic lobsters within an ammonoid body chamber.

    Directory of Open Access Journals (Sweden)

    Adiël A Klompmaker

    Full Text Available Direct animal behavior can be inferred from the fossil record only in exceptional circumstances. The exceptional mode of preservation of ammonoid shells in the Posidonia Shale (Lower Jurassic, lower Toarcian of Dotternhausen in southern Germany, with only the organic periostracum preserved, provides an excellent opportunity to observe the contents of the ammonoid body chamber because this periostracum is translucent. Here, we report upon three delicate lobsters preserved within a compressed ammonoid specimen of Harpoceras falciferum. We attempt to explain this gregarious behavior. The three lobsters were studied using standard microscopy under low angle light. The lobsters belong to the extinct family of the Eryonidae; further identification was not possible. The organic material of the three small lobsters is preserved more than halfway into the ammonoid body chamber. The lobsters are closely spaced and are positioned with their tails oriented toward each other. The specimens are interpreted to represent corpses rather than molts. The lobsters probably sought shelter in preparation for molting or against predators such as fish that were present in Dotternhausen. Alternatively, the soft tissue of the ammonoid may have been a source of food that attracted the lobsters, or it may have served as a long-term residency for the lobsters (inquilinism. The lobsters represent the oldest known example of gregariousness amongst lobsters and decapods in the fossil record. Gregarious behavior in lobsters, also known for extant lobsters, thus developed earlier in earth's history than previously known. Moreover, this is one of the oldest known examples of decapod crustaceans preserved within cephalopod shells.

  2. Size-dependent avoidance of a strong magnetic anomaly in Caribbean spiny lobsters.

    Science.gov (United States)

    Ernst, David A; Lohmann, Kenneth J

    2018-03-01

    On a global scale, the geomagnetic field varies predictably across the Earth's surface, providing animals that migrate long distances with a reliable source of directional and positional information that can be used to guide their movements. In some locations, however, magnetic minerals in the Earth's crust generate an additional field that enhances or diminishes the overall field, resulting in unusually steep gradients of field intensity within a limited area. How animals respond to such magnetic anomalies is unclear. The Caribbean spiny lobster, Panulirus argus , is a benthic marine invertebrate that possesses a magnetic sense and is likely to encounter magnetic anomalies during migratory movements and homing. As a first step toward investigating whether such anomalies affect the behavior of lobsters, a two-choice preference experiment was conducted in which lobsters were allowed to select one of two artificial dens, one beneath a neodymium magnet and the other beneath a non-magnetic weight of similar size and mass (control). Significantly more lobsters selected the control den, demonstrating avoidance of the magnetic anomaly. In addition, lobster size was found to be a significant predictor of den choice: lobsters that selected the anomaly den were significantly smaller as a group than those that chose the control den. Taken together, these findings provide additional evidence for magnetoreception in spiny lobsters, raise the possibility of an ontogenetic shift in how lobsters respond to magnetic fields, and suggest that magnetic anomalies might influence lobster movement in the natural environment. © 2018. Published by The Company of Biologists Ltd.

  3. Forecasting the Seasonal Timing of Maine's Lobster Fishery

    Directory of Open Access Journals (Sweden)

    Katherine E. Mills

    2017-11-01

    Full Text Available The fishery for American lobster is currently the highest-valued commercial fishery in the United States, worth over US$620 million in dockside value in 2015. During a marine heat wave in 2012, the fishery was disrupted by the early warming of spring ocean temperatures and subsequent influx of lobster landings. This situation resulted in a price collapse, as the supply chain was not prepared for the early and abundant landings of lobsters. Motivated by this series of events, we have developed a forecast of when the Maine (USA lobster fishery will shift into its high volume summer landings period. The forecast uses a regression approach to relate spring ocean temperatures derived from four NERACOOS buoys along the coast of Maine to the start day of the high landings period of the fishery. Tested against conditions in past years, the forecast is able to predict the start day to within 1 week of the actual start, and the forecast can be issued 3–4 months prior to the onset of the high-landings period, providing valuable lead-time for the fishery and its associated supply chain to prepare for the upcoming season. Forecast results are conveyed in a probabilistic manner and are updated weekly over a 6-week forecasting period so that users can assess the certainty and consistency of the forecast and factor the uncertainty into their use of the information in a given year. By focusing on the timing of events, this type of seasonal forecast provides climate-relevant information to users at time scales that are meaningful for operational decisions. As climate change alters seasonal phenology and reduces the reliability of past experience as a guide for future expectations, this type of forecast can enable fishing industry participants to better adjust to and prepare for operating in the context of climate change.

  4. Potential production of the Caribbean spiny lobster (Decapoda, Palinura) fisheries

    OpenAIRE

    Chávez Ortiz, Ernesto Aarón

    2009-01-01

    Spiny lobster Panulirus argus (Latreille, 1804) constitutes the most important fishery of the Caribbean; it accounts for nearly 42,000 tonnes. Evidence suggests that high fishing mortality (F) may have been overexploiting most stocks. An assessment was carried out providing the basis for a sustainable exploitation of the nine most important producing countries. Values were assessed and each fishery was simulated; age structure was reconstructed linking biological, economic, and social variabl...

  5. Changing Ocean, Changing Economics: Impact of Rising Temperatures on the American Lobster Landings and on the US-Canada Lobster Economics in the Emerging Chinese Market

    Science.gov (United States)

    Sun, C. H. J.

    2016-02-01

    Record high temperatures in 2012 pushed the start date of the Maine lobster fishing season three weeks earlier than normal. High landings during a compressed time period more than doubled the volume experienced in June and July. As supply outpaced demand, an average 40% decrease in ex-vessel price significantly reduced fishermen's profitability. This study examined how the timing and location of lobster landings is affected by ocean temperatures, number of trips, distance fished from shore, price, and seasonality. Weekly lobster landings and the number of fishing trips in eastern, central, and western Maine from 2008 to 2014 were combined with NERACOOS buoy temperatures to model the change in productivity. The model shows warming leads to significant increases in landings. We also used monthly landings, prices, and trade of live and processed lobster between the U.S. and Canada from 1990 to 2014 to specify a system of equations that captures how both markets are integrated and how they respond to changing market conditions. The model shows that an increase in landings in both areas leads to an increase in lobster trade and then to an increase in US imports of frozen lobster meat. Furthermore, lobster exports to the emerging Chinese market started to expand after 2012 and grew to account for 21% and 11% of the exports value from U.S. and Canada, respectively. From 2010 to 2014, a sub-system model is specified to address how increasing demand in the Chinese market for hard-shell lobster could create incentives to delay production and increase the supply of hard-shell live lobster. The full model was then used to explore ways in which this coastal social-ecological system can adapt to increasing ocean temperature and how the integrated global market might alter the economic implications of the next ocean heatwave.

  6. Determination of moulting events in rock lobsters from pleopod clipping.

    Science.gov (United States)

    Gardner, Caleb; Mills, David J

    2013-01-01

    Rock lobster growth is routinely measured for research to optimise management measures such as size limits and quotas. The process of estimating growth is complicated in crustaceans as growth only occurs when the animal moults. As data are typically collected by tag-recapture methods, the timing of moulting events can bias results. For example, if annual moulting events take place within a very short time-at-large after tagging, or if time-at-large is long and no moulting occurs. Classifying data into cases where moulting has / has not occurred during time-at-large can be required and can generally be determined by change in size between release and recapture. However, in old or slow growth individuals the moult increment can be too small to provide surety that moulting has occurred. A method that has been used since the 1970's to determine moulting in rock lobsters involves clipping the distal portion of a pleopod so that any regeneration observed at recapture can be used as evidence of a moult. We examined the use of this method in both tank and long-duration field trials within a marine protected area, which provided access to large animals with smaller growth increments. Our results emphasised that determination of moulting by change in size was unreliable with larger lobsters and that pleopod clipping can assist in identifying moulting events. However, regeneration was an unreliable measure of moulting if clipping occurred less than three months before the moult.

  7. Determination of moulting events in rock lobsters from pleopod clipping.

    Directory of Open Access Journals (Sweden)

    Caleb Gardner

    Full Text Available Rock lobster growth is routinely measured for research to optimise management measures such as size limits and quotas. The process of estimating growth is complicated in crustaceans as growth only occurs when the animal moults. As data are typically collected by tag-recapture methods, the timing of moulting events can bias results. For example, if annual moulting events take place within a very short time-at-large after tagging, or if time-at-large is long and no moulting occurs. Classifying data into cases where moulting has / has not occurred during time-at-large can be required and can generally be determined by change in size between release and recapture. However, in old or slow growth individuals the moult increment can be too small to provide surety that moulting has occurred. A method that has been used since the 1970's to determine moulting in rock lobsters involves clipping the distal portion of a pleopod so that any regeneration observed at recapture can be used as evidence of a moult. We examined the use of this method in both tank and long-duration field trials within a marine protected area, which provided access to large animals with smaller growth increments. Our results emphasised that determination of moulting by change in size was unreliable with larger lobsters and that pleopod clipping can assist in identifying moulting events. However, regeneration was an unreliable measure of moulting if clipping occurred less than three months before the moult.

  8. Microbiological evaluation of South Australian rock lobster meat.

    Science.gov (United States)

    Yap, A S

    1977-12-01

    Samples of frozen precooked rock lobster meat from five South Australian fish-processing plants situated in the West Coast and south-east regions were tested over a period of six months during the 1974/5 lobster fishing season. The most probable number (MPN) of E. coli and coliforms, Staphylococcus aureus and Salmonella, as well as total plate count (TPC) were determined in 480 samples. Monthly geometric mean TPC ranged from 1600/g to 25,000/g. The highest geometric mean of the MPN of coliforms and E. coli were 4.9/g and 1.8/g respectively. The highest geometric mean number of staphylococci was 18.6/g. Salmonella was not detected in the 480 units tested. Only 0.4% of the samples had TPC exceeding 100,000/g. Coliforms and E. coli were not present in 76.1% and 92.7% respectively of the samples tested. Staphylococcus aureus was not detected in 67.7% of the samples. The numbers of organisms in 82% of the samples fall within the microbiological standards proposed by the National Health and Medical Research Council of Australia for frozen precooked foods. The results of this study demonstrate the microbial quality of precooked lobster meat attainable when good manufacturing practices are used.

  9. Observations of the sound producing organs in achelate lobster larvae

    Directory of Open Access Journals (Sweden)

    John A. Fornshell

    2017-06-01

    Full Text Available The Achelata, lobsters lacking claws and having a phyllosoma larva, are divided into two families, the Palinuridae or spiny lobsters and the Scyllaridae or slipper lobsters. Within the Palinuridae adults of two groups were identified by Parker (1884, the Stridentesthat are capable of producing sounds, and the Silentesthat are not known to produce sounds. The Stridentes employ a file-like structure on the dorsal surface of the cephalon and a plectrum consisting of a series of ridges on the proximal segment of the second antenna to produce their sounds. All species of Achelata hatch as an unpigmented thin phyllosoma larva. The phyllosoma larva of the Stridentes have a presumptive file-like structure on the dorsal cephalon. A similar file-like structure is found on the cephalon of one species of Silentes, Palinurellus wienckki, and some but not all of the phyllosoma larvae of the Scyllaridae. No presumptive plectrum is found on the second antenna of any of the phyllosoma larvae. Presence of a presumptive file-like structure on phyllosoma larvae of Silentes and Scyllaridae suggests that the ability to produce sounds may have been lost secondarily in the Silentes and Scyllaridae.

  10. Microphallids in Gammarus insensibilis Stock, 1966 from a Black Sea lagoon: host response to infection.

    Science.gov (United States)

    Kostadinova, A; Mavrodieva, R S

    2005-09-01

    We examined the patterns of parasite melanization in Gammarus insensibilis using data on microphallids from Pomorie Lagoon (Black Sea) in the light of 3 predictions associated with host survival: (i) hosts invest more in defence in an environment where the likelihood for infection is higher; (ii) multiple immune challenges exhaust host reserves and result in decreased melanization rates in older hosts; (iii) host immune response is directed against the cerebral metacercariae of Microphallus papillorobustus that alter amphipod behaviour and are most detrimental to the host. G. insensibilis was capable of melanizing the metacercariae of all four species of trematodes found to be hosted by the amphipods. The frequency of melanization and mean abundance of melanized metacercariae were substantially higher than those observed in the same amphipod-gammarid system on the French Mediterranean coast. However, the rate of melanization was low and showed a significant decrease with amphipod size. Although the 4 species were differentially melanized, the host response was largely directed against Microphallus hoffmanni and M. subdolum. We suggest that (i) the lower melanization efficiency with age is due to the mode of infection, probably leading to loss of haemolymph and monopolization of the defence resources for wound healing and (ii) in the French system, host response focuses on the most prevalent and abundant species.

  11. Watercress and Water Quality: The Effect of Phenethyl Isothiocyanate on the Mating Behaviour of Gammarus pulex

    Directory of Open Access Journals (Sweden)

    Melanie J. Dixon

    2011-01-01

    Full Text Available Watercress releases phenethyl isothiocyanate (PEITC upon wounding as a defence against herbivores. PEITC levels released from watercress farms are elevated due to cropping, washing, and processing and are thought to lead to adverse effects on Gammarus pulex in chalk streams. This study elucidates the sublethal effect of PEITC on reproductive behaviour of G. pulex, employing ex situ tests to investigate the disruption of precopular pairing under conditions simulating in situ exposure. Mean time to separation of precopular pairs was 89 ± 6 minutes for watercress wash water (1 g watercress per litre water and 81 ± 15 minutes for pure PEITC (1 μL/L. Re-exposure to watercress wash water to simulate the pulsed operation at a watercress farm did not alter behavioural response. The repeated interruption of reproductive behaviour under in situ conditions would impair long-term reproductive success and could explain in part low abundance of G. pulex downstream of watercress farms.

  12. Physiological and behavioural responses of Gammarus pulex (Crustacea: Amphipoda) exposed to cadmium

    International Nuclear Information System (INIS)

    Felten, V.; Charmantier, G.; Mons, R.; Geffard, A.; Rousselle, P.; Coquery, M.; Garric, J.; Geffard, O.

    2008-01-01

    The aim of this study was to investigate the effects of cadmium on physiological and behavioural responses in Gammarus pulex. In a first experiment, cadmium LC50s for different times were evaluated in 264 h experiment under continuous mode of exposure (LC50 96h = 82.1 μg L -1 , LC50 120h = 37.1 μg L -1 , LC50 168h = 21.6 μg L -1 , LC50 264h = 10.5 μg L -1 ). In a second experiment, the physiological and behavioural responses of the amphipod exposed to cadmium (0, 7.5 and 15 μg L -1 ) were investigated under laboratory conditions. The mortality and the whole body cadmium concentration of organisms exposed to cadmium were significantly higher than in controls. Concerning physiological responses, cadmium exposure exerted a significant decrease on osmolality and haemolymph Ca 2+ concentration, but not on haemolymph Na + and Cl - concentrations, whereas the Na + /K + -ATPase activity was significantly increased. Behavioural responses, such as feeding rate, locomotor and ventilatory activities, were significantly reduced in Cd exposed organisms. Mechanism of cadmium action and consequent energetic reallocation in favour of maintenance functions (i.e., osmoregulation) are discussed. The results of this study indicate that osmolality and locomotor activity in G. pulex could be effective ecophysiological/behavioural markers to monitor freshwater ecosystem and to assess the health of organisms

  13. Effect of water quality and confounding factors on digestive enzyme activities in Gammarus fossarum.

    Science.gov (United States)

    Charron, L; Geffard, O; Chaumot, A; Coulaud, R; Queau, H; Geffard, A; Dedourge-Geffard, O

    2013-12-01

    The feeding activity and subsequent assimilation of the products resulting from food digestion allow organisms to obtain energy for growth, maintenance and reproduction. Among these biological parameters, we studied digestive enzymes (amylase, cellulase and trypsin) in Gammarus fossarum to assess the impact of contaminants on their access to energy resources. However, to enable objective assessment of a toxic effect of decreased water quality on an organisms' digestive capacity, it is necessary to establish reference values based on its natural variability as a function of changing biotic and abiotic factors. To limit the confounding influence of biotic factors, a caging approach with calibrated male organisms from the same population was used. This study applied an in situ deployment at 23 sites of the Rhone basin rivers, complemented by a laboratory experiment assessing the influence of two abiotic factors (temperature and conductivity). The results showed a small effect of conductivity on cellulase activity and a significant effect of temperature on digestive enzyme activity but only at the lowest temperature (7 °C). The experimental conditions allowed us to define an environmental reference value for digestive enzyme activities to select sites where the quality of the water impacted the digestive capacity of the organisms. In addition to the feeding rate, this study showed the relevance of digestive enzymes as biomarkers to be used as an early warning tool to reflect organisms' health and the chemical quality of aquatic ecosystems.

  14. Microphallids in Gammarus insensibilis Stock, 1966 from a Black Sea lagoon: manipulation hypothesis going East?

    Science.gov (United States)

    Kostadinova, A; Mavrodieva, R S

    2005-09-01

    Patterns of parasite site selection, variation in infection parameters and interspecific associations are examined in the light of new field data on larval microphallids in Gammarus insensibilis from a Black Sea lagoon. These patterns are discussed in relation to the predictions for the manipulative effect of Microphallus papillorobustus and its relationships with the other microphallid species based on studies on the French Mediterranean coast. Four species were recovered: Maritrema subdolum, Microphallus hoffmanni, M. papillorobustus and Levinseniella propinqua. The latter two were located in both corporal and cephalic segments, but the selection of brain appeared stronger for L. propinqua. M. subdolum was the first colonizer of amphipod population recruits, and unequivocally the dominant species in the lagoon. There was a significant positive relationship between the parasite load of all 4 species. Concurrent infections were exceedingly frequent, and no departures from random association were detected. We found no evidence that the cerebral metacercariae of M. papillorobustus consistently predict the parasite load of any of the other species in the system and identify sources for heterogeneity that may account for the differences between the Black Sea and the Mediterranean system: habitat heterogeneity, bird diversity and host-parasite systems used to infer relationships between microphallids.

  15. Transgenerational deleterious effects of ocean acidification on the reproductive success of a keystone crustacean (Gammarus locusta).

    Science.gov (United States)

    Borges, Francisco O; Figueiredo, Cátia; Sampaio, Eduardo; Rosa, Rui; Grilo, Tiago F

    2018-07-01

    Ocean acidification (OA) poses a global threat to marine biodiversity. Notwithstanding, marine organisms may maintain their performance under future OA conditions, either through acclimation or evolutionary adaptation. Surprisingly, the transgenerational effects of high CO 2 exposure in crustaceans are still poorly understood. For the first time, the present study investigated the transgenerational effect of OA, from hatching to maturity, of a key amphipod species (Gammarus locusta). Negative transgenerational effects were observed on survival of the acidified lineage, resulting in significant declines (10-15%) compared to the control groups in each generation. Mate-guarding duration was also significantly reduced under high CO 2 and this effect was not alleviated by transgenerational acclimation, indicating that precopulatory behaviours can be disturbed under a future high CO 2 scenario. Although OA may initially stimulate female investment, transgenerational exposure led to a general decline in egg number and fecundity. Overall, the present findings suggest a potential fitness reduction of natural populations of G. locusta in a future high CO 2 ocean, emphasizing the need of management tools towards species' sustainability. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Parasitic manipulation and neuroinflammation: Evidence from the system Microphallus papillorobustus (Trematoda - Gammarus (Crustacea

    Directory of Open Access Journals (Sweden)

    Thomas Frederic

    2010-04-01

    Full Text Available Abstract Background Neuropathological consequences of neuroinflammatory processes have been implicated in a wide range of diseases affecting the central nervous system (CNS. Glial cells, the resident immune cells of the CNS, respond to tissue injury by releasing proinflammatory cytokines and free radicals such as nitric oxide. We explored the possibility that neuroimmune responses are involved in parasitic manipulation of host behavior in a trematode-crustacean association. The cerebral larva of the flatworm Microphallus papillorobustus alters responses to environmental stimuli - and thus reflex pathways - in the crustacean Gammarus insensibilis, in a way that enhances predation of the crustacean by birds, definitive hosts of the parasite. Results Immunocytochemical experiments followed by confocal microscopy were performed to study the distribution of glutamine synthetase, a glial cell marker, and nitric oxide synthase in the brain of gammarids. Astrocyte-like glia and their processes were abundant at the surface of the parasites while levels of nitric oxide synthase were elevated at the host-parasite interface in the brain of gammarids harboring mature cerebral larvae and demonstrating altered behavior. Conclusion Taken together these results lend support to the neuroinflammation hypothesis whereby a chronic CNS specific immune response induced by the parasite plays a role in the disruption of neuromodulation, neuronal integrity, and behavior in infected hosts.

  17. Investigation of heavy metals (Cadmium, Lead in Chironomidae and Gammarus pulex Namrood River – Tehran Province

    Directory of Open Access Journals (Sweden)

    Rezaei M. Kamali A. and Shapoori M.

    2012-01-01

    Full Text Available Marine ecosystem pollution is one of the important problems of today environment. In this study the existence of heavy metal in the Namrood River, situated in Firoozkooh in Tehran province, Iran has been investigated. The Namrood River is located near Firoozkooh route, and is affected by pollutant from tourist centers, entertainment, gas stations, nearby villages’ sewage systems, farming effluent, and hatchery farms. In some areas, its water is heavily polluted possibly by heavy metals. After selecting two stations in upstream and downstream of the river, they were sampled three times in both cold and hot seasons of year (mid-March, and June for Chironomidae, and Gammarus plux sediments. The measured heavy metals were cadmium and lead. The results showed that the concentration of cadmium in measured samples varied from 0.010-0.2033 ppm. The concentration of lead in samples varied from 0.11-2.16 ppm. The results also indicated that sediments of samples taken from the upper station in the cold season had a higher proportion of cadmium and a higher concentration of lead  than  sediments in the lower station during the hot season.

  18. Salinity modulates thermotolerance, energy metabolism and stress response in amphipods Gammarus lacustris

    Directory of Open Access Journals (Sweden)

    Kseniya P. Vereshchagina

    2016-11-01

    Full Text Available Temperature and salinity are important abiotic factors for aquatic invertebrates. We investigated the influence of different salinity regimes on thermotolerance, energy metabolism and cellular stress defense mechanisms in amphipods Gammarus lacustris Sars from two populations. We exposed amphipods to different thermal scenarios and determined their survival as well as activity of major antioxidant enzymes (peroxidase, catalase, glutathione S-transferase and parameters of energy metabolism (content of glucose, glycogen, ATP, ADP, AMP and lactate. Amphipods from a freshwater population were more sensitive to the thermal challenge, showing higher mortality during acute and gradual temperature change compared to their counterparts from a saline lake. A more thermotolerant population from a saline lake had high activity of antioxidant enzymes. The energy limitations of the freshwater population (indicated by low baseline glucose levels, downward shift of the critical temperature of aerobic metabolism and inability to maintain steady-state ATP levels during warming was observed, possibly reflecting a trade-off between the energy demands for osmoregulation under the hypo-osmotic condition of a freshwater environment and protection against temperature stress.

  19. Comparison of arsenate and cadmium toxicity in a freshwater amphipod (Gammarus pulex)

    International Nuclear Information System (INIS)

    Vellinger, Céline; Parant, Marc; Rousselle, Philippe; Immel, Françoise

    2012-01-01

    Cadmium is largely documented on freshwater organisms while arsenic, especially arsenate, is rarely studied. The kinetic of the LC50s values for both metals was realized on Gammarus pulex. Physiological [i.e. metal concentration in body tissues, bioconcentration factor (BCF)] effects and behavioural responses (via pleopods beats) were investigated after 240-h exposure. Arsenate LC50 value was 100 fold higher than Cd-LC50 value after 240-h exposure, while concentrations in gammarids were similar for both metals at their respective LC50s. BCF decreased with increasing cadmium concentration while BCF remained stable with increasing arsenate concentration. Moreover, BCF was between 148 and 344 times lower for arsenate than cadmium. A significant hypoventilation was observed for cadmium concentrations exceeding or close to the 240h-LC50 Cd , while gammarids hyperventilated for the lowest arsenate concentrations and hypoventilated for the highest arsenate concentrations. We discussed the relationships between potential action mechanisms of these two metals and observed results. - Highlights: ► First study of arsenate toxicity in a Crustacean gammarid. ► Specific toxicological and behavioural responses to AsV and Cd contamination. ► Each metal led to specific-action mechanisms. ► Different energetic reallocation could explain specific behavioural responses. - This study brings to light the potential relationship between toxicological effects and behavioural responses of G. pulex exposed at both Cadmium and Arsenate.

  20. Asellus and Gammarus spp. (Crustacea) in changing environments: effects of acid stress and habitat permanence

    Energy Technology Data Exchange (ETDEWEB)

    Hargeby, A.

    1993-03-01

    The research underlying this thesis included laboratory and field studies on how acid stress affects the benthic crustaceans Asellus aquaticus L. and Gammarus pulex (L.). A laboratory chamber was constructed to study growth and survival of G. pulex during acid stress. Low pH (6.0) caused 64-92% mortality within three weeks and reduced growth rate and food conversion efficiency in surviving animals. In a field experiment along a pH gradient, the mortality of G. pulex increased below pH 6. The whole-body content of sodium and potassium was reduced in surviving individuals, indicating osmoregulatory disturbance. In Asellus aquaticus, mortality was not affected by pH within the tested range (4.3-7.5). Laboratory experiments showed that interspecific interactions between A. aquaticus and G. pulex can include both exploitative competition and predation by G. pulex on A. aquaticus. Effects of seasonal habitat alterations was studied in a lake by comparing invertebrate assemblages associated with two species of submerged macroalgae (Characea), one perennial and one senescent during autumn. (28 refs.).

  1. The functional and physiological status of Gammarus fossarum (Crustacea; Amphipoda) exposed to secondary treated wastewater

    International Nuclear Information System (INIS)

    Bundschuh, Mirco; Zubrod, Jochen P.; Schulz, Ralf

    2011-01-01

    Climate change scenarios predict lower flow rates during summer that may lead to higher proportions of wastewater in small and medium sized streams. Moreover, micropollutants (e.g. pharmaceuticals and other contaminants) continuously enter aquatic environments via treated wastewater. However, there is a paucity of knowledge, whether extended exposure to secondary treated wastewater disrupts important ecosystem functions, e.g. leaf breakdown. Therefore, the amphipod shredder Gammarus fossarum was exposed to natural stream water (n = 34) and secondary treated wastewater (n = 32) for four weeks in a semi-static test system under laboratory conditions. G. fossarum exposed to wastewater showed significant reductions in feeding rate (25%), absolute consumption (35%), food assimilation (50%), dry weight (18%) and lipid content (22%). Thus, high proportions of wastewater in the stream flow may affect both the breakdown rates of leaf material and thus the availability of energy for the aquatic food web as well as the energy budget of G. fossarum. - Micropollutants in wastewater cause functional and physiological alteration in a leaf-shredding amphipod.

  2. 76 FR 54727 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Science.gov (United States)

    2011-09-02

    ... RIN 0648-AY72 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of...) have submitted Amendment 10 to the Fishery Management Plan for the Spiny Lobster Fishery of the Gulf of... actions to revise the lobster species contained within the fishery management unit; revise definitions of...

  3. 76 FR 59102 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Science.gov (United States)

    2011-09-23

    ... Atlantic; Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment 10 AGENCY: National... Fishery Management Plan for the Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic (FMP), as... implemented, this rule would revise the lobster species contained within the fishery management unit...

  4. 77 FR 25116 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Science.gov (United States)

    2012-04-27

    ...-BB44 Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf... (Councils) have submitted Amendment 11 to the Fishery Management Plan for the Spiny Lobster Fishery of the... proposes to limit spiny lobster fishing using trap gear in certain areas in the exclusive economic zone off...

  5. 50 CFR 697.19 - Trap limits and trap tag requirements for vessels fishing with lobster traps.

    Science.gov (United States)

    2010-10-01

    ... vessels fishing with lobster traps. 697.19 Section 697.19 Wildlife and Fisheries FISHERY CONSERVATION AND... requirements for vessels fishing with lobster traps. (a) Trap limits for vessels fishing or authorized to fish... management area designation certificate or valid limited access American lobster permit specifying one or...

  6. 76 FR 75488 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of the Gulf...

    Science.gov (United States)

    2011-12-02

    ... Atlantic; Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment 10 AGENCY: National... Plan for the Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic (FMP), as prepared and... the lobster species contained within the fishery management unit; establishes an annual catch limit...

  7. 77 FR 50642 - Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment 11; Correction

    Science.gov (United States)

    2012-08-22

    .... 110908576-2240-02] RIN 0648-BB44 Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment... the final rule to implement Amendment 11 to the Fishery Management Plan for the Spiny Lobster Fishery..., 2012), incorrect latitudinal coordinates for Lobster Trap Gear Closed Areas 16 and 17, and longitudinal...

  8. Which Fishers Are Satisfied in the Caribbean? A Comparative Analysis of Job Satisfaction among Caribbean Lobster Fishers

    Science.gov (United States)

    Monnereau, Iris; Pollnac, Richard

    2012-01-01

    Lobster fishing (targeting the spiny lobster "Panulirus argus") is an important economic activity throughout the Wider Caribbean Region both as a source of income and employment for the local population as well as foreign exchange for national governments. Due to the high unit prices of the product, international lobster trade provides a…

  9. PERCEPTION OF THE MOLTING HORMONE 20-HYDROXECDYSONE BY HOMARUS AMERICANUS: LOCALIZATION OF STEROID RECEPTORS AND EFFECT ON BEHAVIOR

    Science.gov (United States)

    There is growing evidence that hormones, when released from an animal into the environment, act as chemical signals to other organisms. There is also evidence to suggest that hormones are released by lobsters during sexual and agonistic encounters to signal conspecifics. The go...

  10. Manganese induced immune suppression of the lobster, Nephrops norvegicus

    International Nuclear Information System (INIS)

    Hernroth, Bodil; Baden, Susanne P.; Holm, Kristina; Andre, Tove; Soederhaell, Irene

    2004-01-01

    Manganese (Mn) is one of the most abundant elements on earth, particularly in the soft bottom sediments of the oceans. As a micronutrient Mn is essential in the metabolic processes of organisms. However, at high concentrations the metal becomes a neurotoxin with well-documented effects. As a consequence of euthrophication, manganese is released from bottom sediments of coastal areas and the Norway lobsters, Nephrops norvegicus, can experience high levels of bioavailable Mn 2+ . Here, we present the first report showing that Mn also affects several fundamental processes in the mobilisation and activation of immunoactive haemocytes. When N. norvegicus was exposed to a realistic [Mn 2+ ] of 20 mg l -1 for 10 days 24.1 μg ml -1 was recorded in the haemolymph. At this concentration the total haemocyte count was reduced by ca. 60%. By using BrdU as a tracer for cell division, it was shown that the proliferation rate in the haematopoietic tissue did not increase, despite the haemocytepenia. A gene coding for a Runt-domain protein, known to be involved in maturation of immune active haemocytes in a variety of organisms, was identified also in haemocytes of N. norvegicus. The expression of this gene was >40% lower in the Mn-exposed lobsters as judged by using a cDNA probe and the in situ hybridisation technique. In response to non-self molecules, like lipopolysaccharide (LPS), the granular haemocytes of arthropods are known to degranulate and thereby release and activate the prophenoloxidase system, necessary for their immune defence. A degranulation assay, tested on isolated granular haemocytes, showed about 75% lower activity in the Mn-exposed lobsters than that for the unexposed. Furthermore, using an enzymatic assay, the activation per se of prophenoloxidase by LPS was found blocked in the Mn-exposed lobsters. Taken together, these results show that Mn exposure suppressed fundamental immune mechanisms of Norway lobsters. This identifies a potential harm that also

  11. Manganese induced immune suppression of the lobster, Nephrops norvegicus

    Energy Technology Data Exchange (ETDEWEB)

    Hernroth, Bodil [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden)]. E-mail: bodil.hernroth@kmf.gu.se; Baden, Susanne P. [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden); Holm, Kristina [Department of Marine Ecology, Goeteborg University, Kristineberg Marine Research Station, SE-450 34 Fiskebaeckskil (Sweden); Andre, Tove [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden); Soederhaell, Irene [Department of Comparative Physiology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)

    2004-12-10

    Manganese (Mn) is one of the most abundant elements on earth, particularly in the soft bottom sediments of the oceans. As a micronutrient Mn is essential in the metabolic processes of organisms. However, at high concentrations the metal becomes a neurotoxin with well-documented effects. As a consequence of euthrophication, manganese is released from bottom sediments of coastal areas and the Norway lobsters, Nephrops norvegicus, can experience high levels of bioavailable Mn{sup 2+}. Here, we present the first report showing that Mn also affects several fundamental processes in the mobilisation and activation of immunoactive haemocytes. When N. norvegicus was exposed to a realistic [Mn{sup 2+}] of 20 mg l{sup -1} for 10 days 24.1 {mu}g ml{sup -1} was recorded in the haemolymph. At this concentration the total haemocyte count was reduced by ca. 60%. By using BrdU as a tracer for cell division, it was shown that the proliferation rate in the haematopoietic tissue did not increase, despite the haemocytepenia. A gene coding for a Runt-domain protein, known to be involved in maturation of immune active haemocytes in a variety of organisms, was identified also in haemocytes of N. norvegicus. The expression of this gene was >40% lower in the Mn-exposed lobsters as judged by using a cDNA probe and the in situ hybridisation technique. In response to non-self molecules, like lipopolysaccharide (LPS), the granular haemocytes of arthropods are known to degranulate and thereby release and activate the prophenoloxidase system, necessary for their immune defence. A degranulation assay, tested on isolated granular haemocytes, showed about 75% lower activity in the Mn-exposed lobsters than that for the unexposed. Furthermore, using an enzymatic assay, the activation per se of prophenoloxidase by LPS was found blocked in the Mn-exposed lobsters. Taken together, these results show that Mn exposure suppressed fundamental immune mechanisms of Norway lobsters. This identifies a potential

  12. The Radioactivity α and β Evaluation in Fish, Lobster and Shrimps from Donan's River Cilacap

    International Nuclear Information System (INIS)

    Sutjipto; Zainul Kamal

    2002-01-01

    The radioactivity α and β total evaluation in fish, lobster and shrimps from Donan's river Cilacap have been done The determination of α and β total using α and β spectrometry. The result of experimentation showed that radioactivity α and β in fish, lobster and shrimps. Could not use as shore quality because unprepared of the threshold value. (author)

  13. Habitat surrounding patch reefs influences the diet and nutrition of the western rock lobster

    Science.gov (United States)

    In this study the influence of habitat on the diet and nutrition of a common reef-associated generalist consumer, the western rock lobster Panulirus cygnus, was tested. Stable isotopes (13C/12C and 15N/14N) and gut contents were used to assess the diet of lobsters collected from ...

  14. 50 CFR Figure 1 to Part 665 - Carapace Length of Lobsters

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Carapace Length of Lobsters 1 Figure 1 to Part 665 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC... Part 665—Carapace Length of Lobsters ER14JA10.126 ...

  15. Potential virulence factors of bacteria associated with tail fan necrosis in the spiny lobster, Jasus edwardsii.

    Science.gov (United States)

    Zha, H; Jeffs, A; Dong, Y; Lewis, G

    2018-05-01

    Tail fan necrosis (TFN) is a common condition found in commercially exploited spiny lobsters that greatly diminishes their commercial value. Bacteria possessing proteolytic, chitinolytic and lipolytic capabilities were associated with TFN in spiny lobsters, Jasus edwardsii. In this study, 69 bacterial isolates exhibiting all the three enzymatic capabilities from the haemolymph and tail fans of J. edwardsii with and without TFN were further characterized and compared, including morphology, biofilm formation, antimicrobial activity, antimicrobial resistance, and production of siderophores, melanin and ammonia. The genomic patterns of the most common Vibrio crassostreae isolates were also compared between TFN-affected and unaffected lobsters. Biofilm formation was stronger in bacterial isolates from both haemolymph and tail fans of TFN-affected lobsters compared to those from the unaffected lobsters, while melanin production and siderophore production were stronger in the isolates from tail fans of lobsters with TFN. By contrast, the other characteristics of isolates were similar in lobsters with and without TFN. The Vib. crassostreae isolates from the affected lobsters had similar genomic patterns. Overall, the results indicate that in addition to proteolytic, chitinolytic and lipolytic activities, the bacteria associated with TFN commonly have enhanced activity of important virulence factors, including biofilm formation, melanin production and siderophore production. © 2018 John Wiley & Sons Ltd.

  16. Bio-mechanical assessment toward throwing and lifting process of i-LOCA (Innovative Lobster Catcher)

    Science.gov (United States)

    Sudiarno, A.; Dewi, D. S.; Putri, M. A.

    2018-04-01

    Indonesia is the country rich in marine resource, one of which is lobster. East java, one of Indonesian province, especially in Region of Gresik and Lamogan, has very huge potential of lobster. Current condition shown that lobster catch by the fisherman mostly depend on lucky factor, which the lobster unintentionally trapped in fisherman’s fish net. By using this mechanism, the number of lobster catch cannot be optimum. Previous researches have produced two versions of i-LOCA, Innovative Lobster Catcher, a special tool for catching the lobster. Although produce more lobster catch, second version of i-LOCA still needs to be scrutinized, one of that is bio-mechanical assessment. The second version of i-LOCA still has no tool to ease throwing and lifting it into the sea. This condition cause Musculoskeletal Disorder (MSD) toward the fisherman. This research perform bio-mechanical assessment toward throwing and lifting process in order to suggest improvement for i-LOCA as the third version. Based on body moment calculation, we found that throwing and lifting process of third version of i-LOCA, each was 3 times and 2 times better than second version of i-LOCA. Meanwhile, Rapid Entire Body Assessment (REBA) score of throwing and lifting process for third version of i-LOCA can be reduced by 5 points compared to second version of i-LOCA.

  17. Effect of magnetic pulses on Caribbean spiny lobsters: implications for magnetoreception.

    Science.gov (United States)

    Ernst, David A; Lohmann, Kenneth J

    2016-06-15

    The Caribbean spiny lobster, Panulirus argus, is a migratory crustacean that uses Earth's magnetic field as a navigational cue, but how these lobsters detect magnetic fields is not known. Magnetic material thought to be magnetite has previously been detected in spiny lobsters, but its role in magnetoreception, if any, remains unclear. As a first step toward investigating whether lobsters might have magnetite-based magnetoreceptors, we subjected lobsters to strong, pulsed magnetic fields capable of reversing the magnetic dipole moment of biogenic magnetite crystals. Lobsters were subjected to a single pulse directed from posterior to anterior and either: (1) parallel to the horizontal component of the geomagnetic field (i.e. toward magnetic north); or (2) antiparallel to the horizontal field (i.e. toward magnetic south). An additional control group was handled but not subjected to a magnetic pulse. After treatment, each lobster was tethered in a water-filled arena located within 200 m of the capture location and allowed to walk in any direction. Control lobsters walked in seemingly random directions and were not significantly oriented as a group. In contrast, the two groups exposed to pulsed fields were significantly oriented in approximately opposite directions. Lobsters subjected to a magnetic pulse applied parallel to the geomagnetic horizontal component walked westward; those subjected to a pulse directed antiparallel to the geomagnetic horizontal component oriented approximately northeast. The finding that a magnetic pulse alters subsequent orientation behavior is consistent with the hypothesis that magnetoreception in spiny lobsters is based at least partly on magnetite-based magnetoreceptors. © 2016. Published by The Company of Biologists Ltd.

  18. A holistic view of dietary carbohydrate utilization in lobster: digestion, postprandial nutrient flux, and metabolism.

    Science.gov (United States)

    Rodríguez-Viera, Leandro; Perera, Erick; Casuso, Antonio; Perdomo-Morales, Rolando; Gutierrez, Odilia; Scull, Idania; Carrillo, Olimpia; Martos-Sitcha, Juan A; García-Galano, Tsai; Mancera, Juan Miguel

    2014-01-01

    Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2-6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6-12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other nutrients.

  19. A holistic view of dietary carbohydrate utilization in lobster: digestion, postprandial nutrient flux, and metabolism.

    Directory of Open Access Journals (Sweden)

    Leandro Rodríguez-Viera

    Full Text Available Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2-6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6-12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other

  20. The insecticide imidacloprid causes mortality of the freshwater amphipod Gammarus pulex by interfering with feeding behavior.

    Directory of Open Access Journals (Sweden)

    Anna-Maija Nyman

    Full Text Available If an organism does not feed, it dies of starvation. Even though some insecticides which are used to control pests in agriculture can interfere with feeding behavior of insects and other invertebrates, the link from chemical exposure via affected feeding activity to impaired life history traits, such as survival, has not received much attention in ecotoxicology. One of these insecticides is the neonicotinoid imidacloprid, a neurotoxic substance acting specifically on the insect nervous system. We show that imidacloprid has the potential to indirectly cause lethality in aquatic invertebrate populations at low, sublethal concentrations by impairing movements and thus feeding. We investigated feeding activity, lipid content, immobility, and survival of the aquatic arthropod Gammarus pulex under exposure to imidacloprid. We performed experiments with 14 and 21 days duration, both including two treatments with two high, one day pulses of imidacloprid and one treatment with a low, constant concentration. Feeding of G. pulex as well as lipid content were significantly reduced under exposure to the low, constant imidacloprid concentration (15 µg/L. Organisms were not able to move and feed--and this caused high mortality after 14 days of constant exposure. In contrast, feeding and lipid content were not affected by repeated imidacloprid pulses. In these treatments, animals were mostly immobilized during the chemical pulses but did recover relatively fast after transfer to clean water. We also performed a starvation experiment without exposure to imidacloprid which showed that starvation alone does not explain the mortality in the constant imidacloprid exposure. Using a multiple stressor toxicokinetic-toxicodynamic modeling approach, we showed that both starvation and other toxic effects of imidacloprid play a role for determining mortality in constant exposure to the insecticide.

  1. Antibiotic mixture effects on growth of the leaf-shredding stream detritivore Gammarus fossarum.

    Science.gov (United States)

    Bundschuh, Mirco; Hahn, Torsten; Gessner, Mark O; Schulz, Ralf

    2017-05-01

    Pharmaceuticals contribute greatly to human and animal health. Given their specific biological targets, pharmaceuticals pose a significant environmental risk by affecting organisms and ecosystem processes, including leaf-litter decomposition. Although litter decomposition is a central process in forest streams, the consequences of exposure to pharmaceuticals remain poorly known. The present study assessed the impact of antibiotics as an important class of pharmaceuticals on the growth of the leaf-shredding amphipod Gammarus fossarum over 24 days. Exposure scenarios involved an antibiotic mixture (i.e. sulfamethoxazole, trimethoprim, erythromycin-H 2 O, roxithromycin, clarithromycin) at 0, 2 and 200 µg/L to assess impacts resulting from exposure to both water and food. The antibiotics had no effect on either leaf-associated fungal biomass or bacterial abundance. However, modification of leaf quality (e.g. through shifts in leaf-associated microbial communities) may have triggered faster growth of gammarids (assessed in terms of body mass gain) at the low antibiotic concentration relative to the control. At 200 µg/L, however, gammarid growth was not stimulated. This outcome might be due to a modified ability of the gut microflora to assimilate nutrients and carbon. Furthermore, the observed lack of increases in the diameter of the gammarids' peduncles, despite an increase in gammarid mass, suggests antibiotic-induced effects in the moulting cycle. Although the processes responsible for the observed effects have not yet been identified, these results suggest a potential role of food-quality, gammarid gut microflora and alteration in the moulting cycle in mediating impacts of antibiotics on these detritivores and the leaf decomposition process in streams.

  2. The Insecticide Imidacloprid Causes Mortality of the Freshwater Amphipod Gammarus pulex by Interfering with Feeding Behavior

    Science.gov (United States)

    Nyman, Anna-Maija; Hintermeister, Anita; Schirmer, Kristin; Ashauer, Roman

    2013-01-01

    If an organism does not feed, it dies of starvation. Even though some insecticides which are used to control pests in agriculture can interfere with feeding behavior of insects and other invertebrates, the link from chemical exposure via affected feeding activity to impaired life history traits, such as survival, has not received much attention in ecotoxicology. One of these insecticides is the neonicotinoid imidacloprid, a neurotoxic substance acting specifically on the insect nervous system. We show that imidacloprid has the potential to indirectly cause lethality in aquatic invertebrate populations at low, sublethal concentrations by impairing movements and thus feeding. We investigated feeding activity, lipid content, immobility, and survival of the aquatic arthropod Gammarus pulex under exposure to imidacloprid. We performed experiments with 14 and 21 days duration, both including two treatments with two high, one day pulses of imidacloprid and one treatment with a low, constant concentration. Feeding of G. pulex as well as lipid content were significantly reduced under exposure to the low, constant imidacloprid concentration (15 µg/L). Organisms were not able to move and feed – and this caused high mortality after 14 days of constant exposure. In contrast, feeding and lipid content were not affected by repeated imidacloprid pulses. In these treatments, animals were mostly immobilized during the chemical pulses but did recover relatively fast after transfer to clean water. We also performed a starvation experiment without exposure to imidacloprid which showed that starvation alone does not explain the mortality in the constant imidacloprid exposure. Using a multiple stressor toxicokinetic-toxicodynamic modeling approach, we showed that both starvation and other toxic effects of imidacloprid play a role for determining mortality in constant exposure to the insecticide. PMID:23690941

  3. The subtle effects of sea water acidification on the amphipod Gammarus locusta

    Directory of Open Access Journals (Sweden)

    J. Williams

    2009-08-01

    Full Text Available We report an investigation of the effects of increases in pCO2 on the survival, growth and molecular physiology of the neritic amphipod Gammarus locusta which has a cosmopolitan distribution in estuaries. Amphipods were reared from juvenile to mature adult in laboratory microcosms at three different levels of pH in nominal range 8.1–7.6. Growth rate was estimated from weekly measures of body length. At sexual maturity the amphipods were sacrificed and assayed for changes in the expression of genes coding for a heat shock protein (hsp70 gene and the metabolic enzyme glyceraldehyde-3-phosphate dehydrogenase (gapdh gene. The data show that the growth and survival of this species is not significantly impacted by a decrease in sea water pH of up to 0.5 units. Quantitative real-time PCR analysis indicated that there was no significant effect of growth in acidified sea water on the sustained expression of the hsp70 gene. There was a consistent and significant increase in the expression of the gapdh gene at a pH of ~7.5 which, when combined with observations from other workers, suggests that metabolic changes may occur in response to acidification. It is concluded that sensitive assays of tissue physiology and molecular biology should be routinely employed in future studies of the impacts of sea water acidification as subtle effects on the physiology and metabolism of coastal marine species may be overlooked in conventional gross "end-point" studies of organism growth or mortality.

  4. Differential tolerance of two Gammarus pulex populations transplanted from different metallogenic regions to a polymetal gradient.

    Science.gov (United States)

    Khan, Farhan R; Irving, Jennifer R; Bury, Nicolas R; Hogstrand, Christer

    2011-03-01

    The River Hayle, Cornwall, UK exhibits pronounced Cu and Zn concentration gradients which were used to compare the metal handling abilities of two populations of Gammarus pulex (Crustacea: Amphipoda). One population was native to the Hayle region (Drym) and presumably has been historically impacted by elevated Cu and Zn levels, whilst naïve gammarids were collected from the River Cray, Kent, UK. Both populations were subject to a 32 day in situ exposure at four R. Hayle sites (Drym, Godolphin, Relubbus and St. Erth). Mortality (LT50), Cu and Zn accumulation and sub-cellular distribution, and oxidative stress (malondialdehyde production) increased with the expected Cu and Zn bioavailabilities at the four sites (i.e. Godolphin>Relubbus>St. Erth>Drym). The naïve population experienced greater metal induced effects in terms of Cu and Zn accumulation, oxidative stress responses and lower LT50s. Analysis of Cu and Zn sub-cellular distribution, however, revealed no significant differences in metal handling. In both populations each metal was localised predominantly to the sub-cellular fraction containing metal bound to metallothionein-like proteins (MTLP) or that holding both metal-rich granules (MRG) and exoskeleton, MTLP and MRG binding being indicative of metal detoxification. However, a greater capacity for detoxified metal storage is not a mechanism implicated in the perceived tolerance of the historically impacted gammarids. Instead our results suggest that the historically impacted population was adapted for lower uptake of Cu and Zn leading to lower bioaccumulation, stress response and ultimately mortality. These results demonstrate not only the usefulness of the in situ methodology, but also that differences in population exposure history can cause significant differences in metal responses during exposure at higher concentrations. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Technetium-99 in lobsters from the western Irish sea

    International Nuclear Information System (INIS)

    Fegan, Mary

    1999-05-01

    Technetium-99, the most important radionuclide of technetium release to the environment, is a pure beta emitter with a half-life of 2.13 x 10(5) years. It behaves conservatively in seawater and is likely to remain available to biota for a long time. The dominant and most stable form of technetium in oxygenated seawater is the pertechnetate ion, Tco4. The principle source of radionuclide contamination of the Irish Sea has been the liquid waste discharges of low level radionuclide effluent from the spent nuclear fuel reprocessing plant at Sellafield on the Cumbria Coast. In 1994 the annual discharge authorization limit for 99Tc was increased from 10 TBq to 200 TBq. Lobster concentrates 99Tc to a high degree with concentration factors of 1x 10(3) reported in the literature. The mean 99Tc activity concentrations in lobsters caught close to Sellafield were reported to have risen by a factor of 20 in 2 years from 390 Bq/kg (wet weight) in 1993 to 8300 Bq/kg (wet weight) in 1995. This study was undertaken to determine the 99Tc activity concentration in lobsters from the western Irish Sea. Lobsters were collected from the east and north east coasts of Ireland over the period June 1997 to July 1998 and analysed using a radioanalytical method which was based on the anion-exchange seperation of technetium as pertechnetate. A gas-flow proportional counter was used to measure to 99Tc activity concentration in each sample. Technetium-99 activity concentrations were measured in the muscle from the tail, the right and the left claws and also in the green gland, the hepatopancreas and the cardiac fore-gut. The results of the measurements showed, as expected, that the 99Tc activity concentrations were not as high as those in the samples from the Cumbrian coast. The mean 99Tc activity concentrations, over the sampling period, in the tail, right and left claw muscles were 214, 124 and 136 BQ/kg (wet weight) respectively. The mean 99Tc activity concentrations in the green gland

  6. Effects of mannan oligosaccharide dietary supplementation on performances of the tropical spiny lobsters juvenile (Panulirus ornatus, Fabricius 1798).

    Science.gov (United States)

    Sang, Huynh Minh; Fotedar, Ravi

    2010-03-01

    The effects of dietary mannan oligosaccharide (MOS) (Bio-Mos, Alltech, USA) on the growth, survival, physiology, bacteria and morphology of the gut and immune response to bacterial infection of tropical rock lobsters (Panulirus ornatus) juvenile were investigated. Dietary inclusion level of MOS at 0.4% was tested against the control diet (trash fish) without MOS inclusion. At the end of 56 days of rearing period, a challenged test was also conducted to evaluate the bacterial infection resistant ability of the lobsters fed the two diets. Lobster juvenile fed MOS diet attained 2.86 +/- 0.07 g of total weigh and 66.67 +/- 4.76% survival rate which were higher (P lobsters fed control diet (2.35 +/- 0.14 g total weight and 54.76 +/- 2.38% survival rate, respectively) thus providing the higher (P lobsters fed MOS diet. Physiological condition indicators such as wet tail muscle index (Tw/B), wet hepatosomatic index (Hiw) and dry tail muscle index (Td/B) of the lobsters fed MOS supplemented diet were higher (P lobsters fed the control diet. Bacteria in the gut (both total aerobic and Vibrio spp.) and gut's absorption surface indicated by the internal perimeter/external perimeter ratio were also higher (P lobsters were fed MOS diet. Lobsters fed MOS diet were in better immune condition showed by higher THC and GC, and lower bacteraemia. Survival, THC, GC were not different among the lobsters fed either MOS or control diet after 3 days of bacterial infection while bacteraemia was lower in the lobsters fed MOS diet. After 7 days of bacterial infection the lobsters fed MOS diet showed higher survival, THC, GC and lower bacteraemia than the lobsters fed the control diet. The experimental trial demonstrated the ability of MOS to improve the growth performance, survival, physiological condition, gut health and immune responses of tropical spiny lobsters juveniles. Copyright 2009 Elsevier Ltd. All rights reserved.

  7. Genetic differentiation of the Iberian amphiodus Gammarus ibericus Margalef, 1951 and G. gauthieri S. Karaman, 1935, with reference to some related species in France

    NARCIS (Netherlands)

    Scheepmaker, Maarten; Meer, van der Frits; Pinkster, Sjouk

    1988-01-01

    Populations of five related species belonging to the Gammarus pulex group from the Iberian Peninsula and southern France have been studied electrophoretically at 21 enzyme loci. Morphologically distinct forms from the same side of the Pyrenees proved to be genetically more similar than

  8. Lobster eye as a collector for water window microscopy

    Science.gov (United States)

    Pina, L.; Maršíková, V.; Inneman, A.; Nawaz, M. F.; Jančárek, A.; Havlíková, R.

    2017-08-01

    Imaging in EUV, SXR and XR spectral bands of radiation is of increasing interest. Material science, biology and hot plasma are examples of relevant fast developing areas. Applications include spectroscopy, astrophysics, Soft X-ray Ray metrology, Water Window microscopy, radiography and tomography. Especially Water Window imaging has still not fully recognized potential in biology and medicine microscopy applications. Theoretical study and design of Lobster Eye (LE) optics as a collector for water window (WW) microscopy and comparison with a similar size ellipsoidal mirror condensor are presented.

  9. Variable X-ray sky with Lobster Eye Telescopes

    International Nuclear Information System (INIS)

    Hudec, R.; Pina, L.; Inneman, A.; Sveda, L.

    2004-01-01

    The variable X-ray sky requires wide-field monitoring with high sensitivity. We refer on novel X-ray telescopes with high sensitivity as well as large field of view. The results are very promising, allowing the proposals for space projects with very wide-field Lobster-eye X-ray optics to be considered. The novel telescopes will monitor the sky with unprecedented sensitivity and angular resolution of order of 1 arcmin. They are expected to contribute essentially to study and to understand various astrophysical objects such as AGN, SNe, GRBs, X-ray flashes, galactic binary sources, stars, CVs, X-ray novae, various transient sources, etc

  10. The impact of gypsum mine water: A case study on morphology and DNA integrity in the freshwater invertebrate, Gammarus balcanicus

    International Nuclear Information System (INIS)

    Ternjej, Ivančica; Mihaljević, Zlatko; Ivković, Marija; Previšić, Ana; Stanković, Igor; Maldini, Krešimir; Želježić, Davor; Kopjar, Nevenka

    2014-01-01

    The aim of our study was to investigate how exposure to heavy metal-rich waters from gypsum mining affects the morphology and levels of primary DNA damage in Gammarus balcanicus. Chemical analysis revealed increased concentrations of metals in water and sediment collected at a site impacted by gypsum mine wastewaters. The specimens also showed elevated total tissue metal levels when compared with the organisms collected at the reference site. The most prominent increase was observed for strontium, followed by iron, nickel, vanadium, aluminium, and manganese. The major pathway of entry for these toxic substances was through the degraded exoskeleton as a consequence of excessive strontium input (unbalanced calcium/strontium ratio) and altered permeability. Disturbed exoskeleton integrity was observed only in individuals collected downstream of the gypsum mine, which was confirmed by electron microscopy. Levels of primary DNA damage were evaluated using the alkaline comet assay in the haemolymph of the specimens. - Highlights: • Our findings suggest toxic potential of gypsum mine wastewaters. • The Gammarus specimens showed elevated total tissue metal levels. • Strontium uptake disturbed exoskeleton integrity. • Corrupted cuticle altered permeability to other toxic substances. • Combined effects of all contaminants caused genotoxicity. - Gypsum mine wastewaters have genotoxic potential and affect the gammarid exoskeleton morphology and biochemistry associated with a high strontium uptake

  11. A biodynamic model predicting waterborne lead bioaccumulation in Gammarus pulex: Influence of water chemistry and in situ validation

    International Nuclear Information System (INIS)

    Urien, N.; Uher, E.; Billoir, E.; Geffard, O.; Fechner, L.C.; Lebrun, J.D.

    2015-01-01

    Metals bioaccumulated in aquatic organisms are considered to be a good indicator of bioavailable metal contamination levels in freshwaters. However, bioaccumulation depends on the metal, the species, and the water chemistry that influences metal bioavailability. In the laboratory, a kinetic model was used to describe waterborne Pb bioaccumulated in Gammarus pulex. Uptake and elimination rate constants were successfully determined and the effect of Ca 2+ on Pb uptake was integrated into the model. Thereafter, accumulated Pb concentrations in organisms were predicted with the model and compared with those measured in native populations from the Seine watershed (France). The predictions had a good agreement with the bioaccumulation levels observed in native gammarids and particularly when the effect of calcium was considered. To conclude, kinetic parameters experimentally derived for Pb in G. pulex are applicable in environmental conditions. Moreover, the consideration of the water's chemistry is crucial for a reliable interpretation of bioaccumulation. - Highlights: • Kinetic model was used to describe waterborne Pb bioaccumulation in G. pulex. • Ca 2+ inhibits Pb uptake by G. pulex in the laboratory. • Model predictions were compared to bioaccumulated Pb in native G. pulex. • Model accurately predicts waterborne bioaccumulated Pb in gammarids. • Considering the influence of Ca 2+ improves the model predictions in the field. - An experimentally-derived kinetic model considering the effect of calcium was relevant to predict the waterborne Pb bioaccumulation in native Gammarus pulex

  12. Carbohydrates digestion and metabolism in the spiny lobster (Panulirus argus): biochemical indication for limited carbohydrate utilization.

    Science.gov (United States)

    Rodríguez-Viera, Leandro; Perera, Erick; Montero-Alejo, Vivian; Perdomo-Morales, Rolando; García-Galano, Tsai; Martínez-Rodríguez, Gonzalo; Mancera, Juan M

    2017-01-01

    As other spiny lobsters, Panulirus argus is supposed to use preferentially proteins and lipids in energy metabolism, while carbohydrates are well digested but poorly utilized. The aim of this study was to evaluate the effect of dietary carbohydrate level on digestion and metabolism in the spiny lobster P. argus . We used complementary methodologies such as post-feeding flux of nutrients and metabolites, as well as measurements of α-amylase expression and activity in the digestive tract. Lobsters readily digested and absorbed carbohydrates with a time-course that is dependent on their content in diet. Lobster showed higher levels of free glucose and stored glycogen in different tissues as the inclusion of wheat flour increased. Modifications in intermediary metabolism revealed a decrease in amino acids catabolism coupled with a higher use of free glucose as carbohydrates rise up to 20%. However, this effect seems to be limited by the metabolic capacity of lobsters to use more than 20% of carbohydrates in diets. Lobsters were not able to tightly regulate α-amylase expression according to dietary carbohydrate level but exhibited a marked difference in secretion of this enzyme into the gut. Results are discussed to highlight the limitations to increasing carbohydrate utilization by lobsters. Further growout trials are needed to link the presented metabolic profiles with phenotypic outcomes.

  13. Carbohydrates digestion and metabolism in the spiny lobster (Panulirus argus: biochemical indication for limited carbohydrate utilization

    Directory of Open Access Journals (Sweden)

    Leandro Rodríguez-Viera

    2017-11-01

    Full Text Available As other spiny lobsters, Panulirus argus is supposed to use preferentially proteins and lipids in energy metabolism, while carbohydrates are well digested but poorly utilized. The aim of this study was to evaluate the effect of dietary carbohydrate level on digestion and metabolism in the spiny lobster P. argus. We used complementary methodologies such as post-feeding flux of nutrients and metabolites, as well as measurements of α-amylase expression and activity in the digestive tract. Lobsters readily digested and absorbed carbohydrates with a time-course that is dependent on their content in diet. Lobster showed higher levels of free glucose and stored glycogen in different tissues as the inclusion of wheat flour increased. Modifications in intermediary metabolism revealed a decrease in amino acids catabolism coupled with a higher use of free glucose as carbohydrates rise up to 20%. However, this effect seems to be limited by the metabolic capacity of lobsters to use more than 20% of carbohydrates in diets. Lobsters were not able to tightly regulate α-amylase expression according to dietary carbohydrate level but exhibited a marked difference in secretion of this enzyme into the gut. Results are discussed to highlight the limitations to increasing carbohydrate utilization by lobsters. Further growout trials are needed to link the presented metabolic profiles with phenotypic outcomes.

  14. Trophic Cascades Induced by Lobster Fishing Are Not Ubiquitous in Southern California Kelp Forests

    Science.gov (United States)

    Guenther, Carla M.; Lenihan, Hunter S.; Grant, Laura E.; Lopez-Carr, David; Reed, Daniel C.

    2012-01-01

    Fishing can trigger trophic cascades that alter community structure and dynamics and thus modify ecosystem attributes. We combined ecological data of sea urchin and macroalgal abundance with fishery data of spiny lobster (Panulirus interruptus) landings to evaluate whether: (1) patterns in the abundance and biomass among lobster (predator), sea urchins (grazer), and macroalgae (primary producer) in giant kelp forest communities indicated the presence of top-down control on urchins and macroalgae, and (2) lobster fishing triggers a trophic cascade leading to increased sea urchin densities and decreased macroalgal biomass. Eight years of data from eight rocky subtidal reefs known to support giant kelp forests near Santa Barbara, CA, USA, were analyzed in three-tiered least-squares regression models to evaluate the relationships between: (1) lobster abundance and sea urchin density, and (2) sea urchin density and macroalgal biomass. The models included reef physical structure and water depth. Results revealed a trend towards decreasing urchin density with increasing lobster abundance but little evidence that urchins control the biomass of macroalgae. Urchin density was highly correlated with habitat structure, although not water depth. To evaluate whether fishing triggered a trophic cascade we pooled data across all treatments to examine the extent to which sea urchin density and macroalgal biomass were related to the intensity of lobster fishing (as indicated by the density of traps pulled). We found that, with one exception, sea urchins remained more abundant at heavily fished sites, supporting the idea that fishing for lobsters releases top-down control on urchin grazers. Macroalgal biomass, however, was positively correlated with lobster fishing intensity, which contradicts the trophic cascade model. Collectively, our results suggest that factors other than urchin grazing play a major role in controlling macroalgal biomass in southern California kelp forests, and

  15. The research of the style of angel lobster eye x-ray optical system

    Science.gov (United States)

    Cheng, HuaQi; Liu, YuJiao; Zhang, ShaoWei; Hou, LinBao; Li, XingLong

    2018-01-01

    This paper has developed the theory research of wide field Angel lobster eye X-ray optical system based on the principle of entirely incidence. Combine the configuration characteristic of lobster eye, recommend the conclusion of beam of light focus on the half of radius whether point or parallel light. Designed the microchannel through the principle of real ray trace and got the relationship among different parameters about it using numerical value emulation. Got pixels and illumination pictures validated the wide field focus characteristic of Angel lobster eye by simulating the optical system.

  16. Disposition of phenanthrene and octachlorostyrene in spiny lobsters, Panulirus argus, after intragastric administration

    International Nuclear Information System (INIS)

    Solbakken, J.E.; Knap, A.H.

    1986-01-01

    Spiny lobster (Panulirus argus) is a commercial crustacean in Bermuda. It was therefore of interest to study the fate of xenobiotics in the species as very little attention has been paid to toxicological studies with spiny lobsters. Earlier it was found that the temperate crustacean, Nephrops norveqicus (Norway lobster) had the ability to accumulate and eliminate phenanthrene. The aim of this investigation was to gain a better understanding of the fate of xenobiotics in crustaceans under different environmental conditions, and to compare the polycyclic aromatic hydrocarbon, phenenthrene, with the more environmentally persistent chlorinated compound octachlorostyrene, a by-product of magnesium metal production

  17. HUBUNGAN PANJANG-BERAT DAN FAKTOR KONDISI LOBSTER BATU (Panulirus penicillatus DI PERAIRAN SELATAN GUNUNG KIDUL DAN PACITAN

    Directory of Open Access Journals (Sweden)

    Moh Fauzi Fauzi

    2016-03-01

    Full Text Available Perairan di sebelah selatan Gunung Kidul dan Pacitan merupakan daerah penangkapan lobster yang cukup potensial. Analisis hubungan panjang berat, faktor kondisi dan sebaran kisaran panjang lobster batu (Panulirus penicillatus di perairan tersebut dilakukan pada bulan Maret 2010 hingga Maret 2012. Pengukuran panjang-berat terhadap 1.803 individu lobster batu menunjukkan pola pertumbuhan yang bersifat allometrik negatif. Faktor kondisi lobster memiliki kesamaan antara jenis kelamin jantan dan betina dan terdapat kecenderungan menurunnya faktor kondisi dengan bertambahnya panjang (umur. Panjang karapas dominan berada pada kisaran antara 45-50mm. Lobster betina yang membawa telur ditemukan pertama kali pada kelas panjang karapas antara 35-40mm. The waters in the south of Gunung Kidul and Pacitan were indicated as a potentially fishing ground of spiny lobster. Analysis of Length-weight relationship, condition factor and distribution of the pronghorn spiny lobster (Panulirus penicillatus in those waters were conducted in March 2010 through March 2012. Length-weight measurements on 1.803 individual lobsters showed allometric negative growth patterns. Lobster have in common condition factor between male and female, and there is a tendency condition factor decreased with increasing length (age. Dominant carapace length is in the range between 45-50mm. Female lobsters carrying eggs were first discovered in the class of carapace length between 35-40mm.

  18. THE PHYSIOLOGICAL AND MORPHOLOGICAL BASIS FOR OLFACTORY PERCEPTION OF STEROIDS DURING AGONISITC BEHAVIOR IN LOBSTER

    Science.gov (United States)

    During fighting, American lobsters urinate on each other with antennule flicking highest during this period. Blocking excretion of urine obliterates previously established dominance relationships, suggesting that individual recognition requires a urine signal (Breithaupt et al.,...

  19. Deep-sea spiny lobster, Puerulus sewelli Ramadan: Its commercial potentialities

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, P.V.; George, M.J.

    Recent exploratory cruises carried out along and outside the continental shelf off the west coast of India have brought to light the existence of spiny lobster in considerable numbers The trawling operations conducted in areas of depths between 200...

  20. Chemosensory neurons in the mouthparts of the spiny lobsters Panulirus argus and Panulirus interruptus (Crustacea : Decapoda)

    DEFF Research Database (Denmark)

    Garm, Anders Lydik; Shabani, Shkelzen; Høeg, Jens Thorvald

    2005-01-01

    We studied electrophysiological properties of single chemosensory neurons in the mouthparts of the spiny lobsters Panulirus argus and Panulirus interruptus to complement our growing understanding of the behavioral roles of mouthparts of decapod crustaceans. Food mixtures and 13 single compounds...

  1. 78 FR 9327 - Hawaii Crustacean Fisheries; 2013 Northwestern Hawaiian Islands Lobster Harvest Guideline

    Science.gov (United States)

    2013-02-08

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 665 RIN 0648-XC453 Hawaii Crustacean Fisheries; 2013 Northwestern Hawaiian Islands Lobster Harvest Guideline AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce...

  2. 76 FR 4551 - Hawaii Crustacean Fisheries; 2011 Northwestern Hawaiian Islands Lobster Harvest Guideline

    Science.gov (United States)

    2011-01-26

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 665 RIN 0648-XA159 Hawaii Crustacean Fisheries; 2011 Northwestern Hawaiian Islands Lobster Harvest Guideline AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce...

  3. Effects of pipelines and gathering lines on snow crab and lobster : final report

    Energy Technology Data Exchange (ETDEWEB)

    Warner, J.L.; Covill, J.D. [Martec Ltd., Halifax, NS (Canada); Gilroy, L.; Wheaton, D.; Holtham, P.; Richards, T.; Lucas, C.; Schattschneider, G.; Religa, R.; Brannan, C. [Defence Research and Development Canada Atlantic, Dartmouth, NS (Canada); DeMont, E.; Schuegraf, M; King, K. [Saint Francis Xavier Univ., Antigonish, NS (Canada). Dept. of Biology

    2004-12-01

    A study investigating potential behavioural changes in lobster after the completion of the ExxonMobil natural gas pipeline in the vicinity of Goldboro, Nova Scotia was presented. The study was divided into 4 components: (1) field studies to measure underwater noise in the region associated with the operational gas pipeline; (2) a determination of the electromagnetic (EM) fields generated by the presence of a pipeline in the region through the creation of a numerical model; (3) a lobster catch-and-release field program to measure lobster catches, with concentrated sampling around the Goldboro pipeline landfall using 2 reference sites; and (4) a separate laboratory based study to determine the scaling and climbing ability of lobsters over 32 and 48 inch simulated gas pipelines with smooth and rough texture protective coatings. Offshore sections of the pipeline are partially or fully exposed above the sea-floor, and the laboratory experiments were conducted to asses the effects of unburied pipelines creating a barrier to lobster movement. Results of the acoustic surveys showed peaks of low frequency sound within the hearing range of lobster in the vicinity of the pipeline. The EM survey and resulting numerical model indicated that the pipeline created a narrow magnetic field affecting an area only 2 to 3 metres wide on either side of the pipeline which produced a field strength up to one third as strong as that of the earth's background magnetic field. The lobster catch and release program showed no statistically significant variation of catches between the pipeline locale and the 2 reference sites. In the laboratory testing, the rough surface coating was found to more scaleable for the lobsters than a smooth coating. 7 tabs., 7 figs.

  4. 77 FR 44168 - Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment 11

    Science.gov (United States)

    2012-07-27

    ... Trap Gear Closed Area 37. Point North Lat. West Long. A 25[deg]07'51.156'' 80[deg]17'27.910'' B 25[deg...'40.998'' A 25[deg]07'51.156'' 80[deg]17'27.910'' (xxxviii) Lobster Trap Gear Closed Area 38. Point...) Lobster Trap Gear Closed Area 51. Point North Lat. West Long. A 25[deg]16'33.006'' 80[deg]13'30.001'' B 25...

  5. 77 FR 28560 - Spiny Lobster Fishery of the Gulf of Mexico and South Atlantic; Amendment 11

    Science.gov (United States)

    2012-05-15

    ...'' (xxxvii) Lobster Trap Gear Closed Area 37. Point North lat. West long. A 25[deg]07'51.156''. 80[deg]17'27... Trap Gear Closed Area 51. Point North lat. West long. A 25[deg]16'33.006''. 80[deg]13'30.001'' B 25[deg...) Lobster Trap Gear Closed Area 55. Point North lat. West long. A 25[deg]21'45.004''. 80[deg]09'51.998'' B...

  6. Microbial Degradation of Lobster Shells to Extract Chitin Derivatives for Plant Disease Management

    Directory of Open Access Journals (Sweden)

    Gayathri Ilangumaran

    2017-05-01

    Full Text Available Biodegradation of lobster shells by chitinolytic microorganisms are an environment safe approach to utilize lobster processing wastes for chitin derivation. In this study, we report degradation activities of two microbes, “S223” and “S224” isolated from soil samples that had the highest rate of deproteinization, demineralization and chitinolysis among ten microorganisms screened. Isolates S223 and S224 had 27.3 and 103.8 protease units mg-1 protein and 12.3 and 11.2 μg ml-1 of calcium in their samples, respectively, after 1 week of incubation with raw lobster shells. Further, S223 contained 23.8 μg ml-1 of N-Acetylglucosamine on day 3, while S224 had 27.3 μg ml-1 on day 7 of incubation with chitin. Morphological observations and 16S rDNA sequencing suggested both the isolates were Streptomyces. The culture conditions were optimized for efficient degradation of lobster shells and chitinase (∼30 kDa was purified from crude extract by affinity chromatography. The digested lobster shell extracts induced disease resistance in Arabidopsis by induction of defense related genes (PR1 > 500-fold, PDF1.2 > 40-fold upon Pseudomonas syringae and Botrytis cinerea infection. The study suggests that soil microbes aid in sustainable bioconversion of lobster shells and extraction of chitin derivatives that could be applied in plant protection.

  7. Temporal variation in the specific dynamic action of juvenile New Zealand rock lobsters, Jasus edwardsii.

    Science.gov (United States)

    Radford, Craig A; Marsden, Islay D; Davison, William

    2004-09-01

    To enhance the on-growing of Jasus edwardsii in culture, it is important to understand the feeding physiology of juveniles. In crustaceans, there is a loss of energy and an increase in oxygen consumption (specific dynamic action or SDA) associated with feeding. The present research measured the SDA of juvenile J. edwardsii fed either in the morning or at night held at 15 degrees C. Closed box respirometry was used to measure oxygen consumption (MO(2)) and ammonia excretion in juvenile lobsters. Juveniles exhibited a nocturnal rhythm in both MO(2) and ammonia excretion. The factorial rise in MO(2) (1.58+/-0.03 times) for lobsters fed in the morning was significantly less than lobsters fed at night (1.80+/-0.01 times). Lobsters fed in the morning had a significantly shorter SDA (30+/-1.2 h) response compared to lobsters fed at night (36+/-1 h). Energy loss as a result of digestion was less for lobsters fed in the morning. Therefore, if juvenile J. edwardsii are fed in the morning, they could optimise the energy content of the meal and this could result in increased growth.

  8. Trophic interactions among grouper (Epinephelus marginatus), octopus (Octopus vulgaris) and red lobster (Palinurus elephas) in the Western Mediterranean

    OpenAIRE

    Quetglas, A. (Antoni); Reñones, O. (Olga); Goñi, R. (Raquel)

    2001-01-01

    In the present paper a first evaluation of the trophic interactions between grouper, octopus and spiny red lobster in the western Mediterranean is presented. The efficiency of octopus preying on lobsters is also estimated from trap catches. Grouper and octopus base their diet on the same major taxonomic groups and this is reflected in the values of diet overlap. Trophic diversity of grouper and octopus is also very similar. The estimation of the octopus efficiency preying on lobsters shows th...

  9. Effect of gender on physiological and behavioural responses of Gammarus roeseli (Crustacea Amphipoda) to salinity and temperature

    International Nuclear Information System (INIS)

    Sornom, Pascal; Felten, Vincent; Medoc, Vincent; Sroda, Sophie; Rousselle, Philippe; Beisel, Jean-Nicolas

    2010-01-01

    The importance of potentially interacting factors in organisms responses to a stress are often ignored or underestimated in ecotoxicology. In laboratory experiments we investigated how gender, temperature and age influence the behaviour and the physiology of the freshwater amphipod Gammarus roeseli under salinity stress. Our results revealed a significant higher sensitivity of females in survival, ventilation and ionoregulation whereas no inter-age differences were reported. Water temperature also exerted a significant effect in survival and ventilation of G. roeseli. Some of those factors appeared to interact significantly. This study provides evidence that gender can affect organisms responses to a stressor and consequently has to be considered while assessing a stress impact. We discussed the potential relationships between biological and behavioural responses. - Influence of gender, age and temperature in a gammarid responses to a stress.

  10. Analog electronic model of the lobster pyloric central pattern generator

    Energy Technology Data Exchange (ETDEWEB)

    Volkovskii, A [Institute for Nonlinear Science, University of California San Diego, CA (United States); Brugioni, S [Institute for Nonlinear Science, University of California San Diego, CA (United States); Istituto Nazionale di Ottica Applicata Largo E. Fermi 6 50125 Florence (Italy); Levi, R [Institute for Nonlinear Science, University of California San Diego, CA (United States); Rabinovich, M [Institute for Nonlinear Science, University of California San Diego, CA (United States); Selverston, A [Institute for Nonlinear Science, University of California San Diego, CA (United States); Abarbane, H D I [Institute for Nonlinear Science, University of California San Diego, CA (United States)

    2005-01-01

    An electronic circuit intended to simulate the nonlinear dynamics of a simplified 3-cell model of the pyloric central pattern generator in California spiny lobster stomato gastric ganglion is presented. The model employs the synaptic phase locked loop (SPLL) concept where the frequency of oscillations of a postsynaptic cell is mainly controlled by the synaptic current which depends on the phase shift between the oscillations. The theoretical study showed that the system has a stable steady state with correct phase shifts between the oscillations and that this regime is stable when the frequency of the pacemaker cell is varied over a wide range. The main bifurcations in the system were studied analytically, in computer simulations, and in experiments with the electronic circuit. The experimental measurements are in good agreement with the expectations of the theoretical model.

  11. Galatheoid squat lobsters (Crustacea: Decapoda: Anomura from Korean waters

    Directory of Open Access Journals (Sweden)

    Jung Nyun Kim

    2016-10-01

    Full Text Available Abstract Ten species of Galatheoidea (squat lobsters, belonging to two families, were collected in the Korean exclusive economic zone: Galathea balssi Miyake and Baba, 1964, Galathea orientalis Stimpson, 1858, Galathea pubescens Stimpson, 1858, and Galathea rubromaculata Miyake and Baba, 1967 belonging to Galatheidae; Bathymunida brevirostris Yokoya, 1933, Cervimunida princeps Benedict, 1902, Munida caesura Macpherson and Baba, 1993, Munida japonica Stimpson, 1858, Munida pherusa Macpherson and Baba, 1993, and Paramunida scabra (Henderson, 1885 belonging to Munididae. The present study comprises the morphological description of these ten species, including drawings and color photographs, a brief review of their regional records, and a key for their identification. Although all species are common in Japanese waters, G. balssi, G. rubromaculata, B. brevirostris, C. princeps, M. caesura, and M. pherusa are new to Korean marine fauna.

  12. Genetic Diversity Approach to Fishery Management Spiny Lobster Southern Waters of Java Based on SWOT Analysis and AHP

    Directory of Open Access Journals (Sweden)

    Florensius Eko Haryono

    2017-05-01

    Full Text Available Indonesia as an archipelagic and tropical country, and known as the centre of megabiodiversity. Tropical spiny lobster consists of several species and able to survive without water for a certain period and this excess used to be distributed life conditions.  Spiny lobster fisheries is become an important issue in Indonesia now, due to the catch condition decrease for some decade, and need a policy to manage. Spiny lobster management strategy based on biodiversity genetic of lobster in Southern of Central Java (SCJ and Special  Region of Jogjakarta (SRJ waters done by collecting the lobster randomly, and collecting the questioner to fisherman, lobster collector, government and NGO from February-August 2015.  Data analyzed by SWOT and AHP methods.   The management priorities based on highest score. The first priority management based on genetic of lobster is not carried out on an isolated by each districts. Second priority management based on genetic lobster was avoid of each district management. Third priority was  optimizing new fishingground.  Fourth priority optimized of habitat utilization, optimized  fishing time, and increased number of fishing trips . Key word : Spiny lobster, diversity genetic, SWOT, AHP.

  13. Pengaruh Kepadatan dan Durasi dalam Kondisi Transportasi Sistem Kering Terhadap Kelulusan Hidup Lobster Air Tawar (Cherax quadricarinatus

    Directory of Open Access Journals (Sweden)

    Theresia Dwi Suryaningrum

    2008-12-01

    selama dalam kondisi transportasi. Kemasan dengan kepadatan 6 ekor/kotak plastik menghasilkan kelulusan hidup yang lebih baik dibandingkan dengan kemasan dengan kepadatan 8 ekor/kotak plastik. Semakin lama waktu dalam kondisi transportasi, semakin rendah kelulusan hidup dan bobot lobster. Durasi dalam kondisi transportasi sampai 7 hari dapat menurunkan bobot lobster sampai 10%. Transportasi lobster dengan kepadatan 6 ekor/kotak plastik selama 6 hari menghasilkan kelulusan hidup 97% dan tetap sehat setelah dibugarkan kembali. Oleh karena itu, lobster air tawar sebaiknya ditransportasikan dengan durasi tidak lebih dari 6 hari.

  14. Research Regarding Somatic Measurements at River Lobster Males (Astacus Fluviatilis

    Directory of Open Access Journals (Sweden)

    Marian Bura

    2010-10-01

    Full Text Available The body measurements was made on 20 males of river lobsters (Astacus fluviatilis or Astacus astacus. The lobsters on witch the study was made had an average total length of body of 12.72 cm ±0.19 cm (formed from: 6.07±0.10cm the length of cefalothorax, 4.73 ±0.10 cm the length of abdomen and 1.91 ±0.07 cm length of telson, and a body weight of 55.70±3.07 g. the males present a length of feelers of 8.53±0.34 cm, a antennas of 2.20±0.05 cm, and the stem of the eyes of 0.51±0.02 cm. The body of male present a average width of 3.35±0.07 cm at level of cefalothorax, and 2.40±0.05 cm at abdomen level. Average deepness of cefalothorax was 2.85±0.07cm, and abdomen deepness of 1.34±0.03cm. The 5 pairs of periopode had an average length of 10.91±0.42 cm, 6.06±0.22 cm, 7.21±0.21 cm, 6.57±0.16 cm and 5.85±0.15cm. The average length of pleopods was at first pear of 2.00±0.06 cm, at second pair of 2.11±0.05 cm, at third of 1.85±0.05 cm, at fourth of 1.73±0.04 cm and at fifth pair of 1.55±0.04 cm.

  15. Lobster processing by-products as valuable bioresource of marine functional ingredients, nutraceuticals, and pharmaceuticals.

    Science.gov (United States)

    Nguyen, Trung T; Barber, Andrew R; Corbin, Kendall; Zhang, Wei

    2017-01-01

    The worldwide annual production of lobster was 165,367 tons valued over $3.32 billion in 2004, but this figure rose up to 304,000 tons in 2012. Over half the volume of the worldwide lobster production has been processed to meet the rising global demand in diversified lobster products. Lobster processing generates a large amount of by-products (heads, shells, livers, and eggs) which account for 50-70% of the starting material. Continued production of these lobster processing by-products (LPBs) without corresponding process development for efficient utilization has led to disposal issues associated with costs and pollutions. This review presents the promising opportunities to maximize the utilization of LPBs by economic recovery of their valuable components to produce high value-added products. More than 50,000 tons of LPBs are globally generated, which costs lobster processing companies upward of about $7.5 million/year for disposal. This not only presents financial and environmental burdens to the lobster processors but also wastes a valuable bioresource. LPBs are rich in a range of high-value compounds such as proteins, chitin, lipids, minerals, and pigments. Extracts recovered from LPBs have been demonstrated to possess several functionalities and bioactivities, which are useful for numerous applications in water treatment, agriculture, food, nutraceutical, pharmaceutical products, and biomedicine. Although LPBs have been studied for recovery of valuable components, utilization of these materials for the large-scale production is still very limited. Extraction of lobster components using microwave, ultrasonic, and supercritical fluid extraction were found to be promising techniques that could be used for large-scale production. LPBs are rich in high-value compounds that are currently being underutilized. These compounds can be extracted for being used as functional ingredients, nutraceuticals, and pharmaceuticals in a wide range of commercial applications

  16. Spatial Variability in Condition of Southern Rock Lobsters (Jasus edwardsii) at the Start of the Tasmanian Fishing Season.

    Science.gov (United States)

    Mendo, Tania; Simon, Cedric; Green, Bridget; Gardner, Caleb

    2016-01-01

    The southern rock lobster (Jasus edwardsii) industry in Australia favours red lobsters, which are usually caught in shallow waters, over paler (brindle) lobsters. This preference is driven partly by the Chinese market, where red is associated with luck and prosperity, and additionally, by the widely held perception within the industry that brindles have greater mortality rates during out of water transport than reds. Limited scientific evidence supports these industry observations; however, these studies did not evaluate the initial condition of lobsters. This study aimed first, to determine which variables better describe condition in J. edwardsii and second, to compare condition among lobsters in several sites around Tasmania at the typical time of high transport mortality. Male lobsters were collected from the South West, South East, East and North coast of Tasmania in late November/December 2014, which correspond to the start of the Tasmanian fishing season. A comprehensive condition assessment was applied by measuring tissue proximal composition, Brix index, Total Haemocyte Count, pH, haemocyanin and another 16 haemolymph parameters of interest. A useful framework to compare condition in J. edwardsii was established by first, using Brix index as a measure of nutritional condition, second, using pH, magnesium, and bicarbonate to evaluate differences in physiological condition and finally, using THC counts as a proxy for lobster health condition. Lobsters from different sites had different nutritional, physiological and health condition, consistent with industry observations, however our results indicate that some red shallow water lobsters exhibited poorer nutritional and health condition, while some deep water brindle lobsters were in good condition. Differences in condition could not be directly associated to catch depth of lobsters and was related to other spatially discrete factors which sometimes vary over distances <3 km.

  17. 76 FR 59377 - Amendments to the Reef Fish, Spiny Lobster, Queen Conch and Coral and Reef Associated Plants and...

    Science.gov (United States)

    2011-09-26

    ... lobster, and aquarium trade species identified by the Secretary as not undergoing overfishing; allocate... effect of the 2011 Caribbean ACL Amendment is prevent overfishing of reef fish, spiny lobster and... be subject to overfishing, ACLs must be established at a level that prevents overfishing and helps to...

  18. Differences in technetium-99 accumulation and distribution between organs in male and female lobsters collected from Norwegian coastal waters

    Energy Technology Data Exchange (ETDEWEB)

    Kolstad, Anne Kathrine; Gjelsvik, Runhild; Rudjord, Anne Liv

    2006-07-01

    In this report, {sup 99}Tc results for lobsters caught along the Norwegian coast between 2001 and 2005 are presented. The high accumulation of {sup 99}Tc in lobsters compared to other crustecea is confirmed in this report, as well as the clear differences between males and females. Concentration factors have been estimated for each gender and also for different organs. (author)

  19. Differences in technetium-99 accumulation and distribution between organs in male and female lobsters collected from Norwegian coastal waters

    International Nuclear Information System (INIS)

    Kolstad, Anne Kathrine; Gjelsvik, Runhild; Rudjord, Anne Liv

    2006-01-01

    In this report, 99 Tc results for lobsters caught along the Norwegian coast between 2001 and 2005 are presented. The high accumulation of 99 Tc in lobsters compared to other crustecea is confirmed in this report, as well as the clear differences between males and females. Concentration factors have been estimated for each gender and also for different organs. (author)

  20. Movement patterns of the spiny lobster Palinurus elephas (Fabricius, 1787 from a central western Mediterranean protected area

    Directory of Open Access Journals (Sweden)

    Maria Cristina Follesa

    2009-09-01

    Full Text Available Movement patterns of the spiny lobster Palinurus elephas were determined from 389 individuals (total tagged 5666 tag-recaptured inside a no-take area of the central western Mediterranean and its surrounding zone. High site association and limited movements in tagged lobsters was observed; 60.4% of lobsters moved less than 2 km from the centre of the area (site of release. No clear relationship between lobster movement pattern and sex or size was observed; however, it seemed that the largest males and females tended to be more resident, thus contributing to the rebuilding of the biomass of local lobsters. Most lobsters undertook migrations in the southwest direction. The increased availability of shelters and food towards the southwest could have contributed to the lobsters’ movement. The results of our research indicate that the small size of the protected area and the scale of the movement exhibited by tagged lobsters allows a proportion of the lobster population to move out of the protected area and become susceptible to capture in the adjacent fishery.

  1. Driving a Fishery along the Bumpy Ride of Today's Globalisation: The Case of the Australian Southern Rock Lobster Association

    NARCIS (Netherlands)

    Dentoni, D.; Lu, J.; English, F.; McBride, R.

    2012-01-01

    The case of the Australian Southern Rock Lobster Association describes real issues faced by the Market Development Manager of a collective agri-food organization (SRL) representing all the southern rock lobster fishermen in Victoria, South Australia and Tasmania. The case deals with recent

  2. 77 FR 76458 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of Puerto...

    Science.gov (United States)

    2012-12-28

    ... the Caribbean, Gulf of Mexico, and South Atlantic; Spiny Lobster Fishery of Puerto Rico and the U.S. Virgin Islands; Exempted Fishing Permit AGENCY: National Marine Fisheries Service (NMFS), National... in the U.S. Virgin Islands. Currently, data on U.S. Caribbean spiny lobster life history are limited...

  3. The Evolution of the Maine Lobster V-Notch Practice: Cooperation in a Prisoner's Dilemma Game

    Directory of Open Access Journals (Sweden)

    James Acheson

    2011-03-01

    Full Text Available The Maine lobster industry is experiencing record high catches because, in all probability, of an effective management program. One of the most important conservation measures is the V-notch program that allows fishermen to conserve proven breeding females by notching the tails of egg-bearing lobsters. Such marked lobsters may never be taken. Although thousands of lobster fishermen participate, it is a voluntary practice. The genesis of this practice is not easily explained, because V-notching poses a prisoner's dilemma problem that gives fishermen an incentive to avoid the practice. The most common explanations for ways to overcome prisoner's dilemma problems will not work in the case of the V-notch. An unusual combination of factors explains the V-notch program: (1 a strong belief among those in the industry that the V-notch is effective in conserving the lobster stock; (2 a low discount rate because the long-term gains from V-notching are higher than the one-time gain from defection; (3 a gain in reputation for those who V-notch. At the start of the 20th century, fishermen did not V-notch; by the end of the century, V-notching was common. We explain the change in strategies using a three-parameter evolutionary model that emphasizes the importance of culture change.

  4. Modeling the focusing efficiency of lobster-eye optics for image shifting depending on the soft x-ray wavelength.

    Science.gov (United States)

    Su, Luning; Li, Wei; Wu, Mingxuan; Su, Yun; Guo, Chongling; Ruan, Ningjuan; Yang, Bingxin; Yan, Feng

    2017-08-01

    Lobster-eye optics is widely applied to space x-ray detection missions and x-ray security checks for its wide field of view and low weight. This paper presents a theoretical model to obtain spatial distribution of focusing efficiency based on lobster-eye optics in a soft x-ray wavelength. The calculations reveal the competition mechanism of contributions to the focusing efficiency between the geometrical parameters of lobster-eye optics and the reflectivity of the iridium film. In addition, the focusing efficiency image depending on x-ray wavelengths further explains the influence of different geometrical parameters of lobster-eye optics and different soft x-ray wavelengths on focusing efficiency. These results could be beneficial to optimize parameters of lobster-eye optics in order to realize maximum focusing efficiency.

  5. Effects of current-use fungicides and their mixtures on the feeding and survival of the key shredder Gammarus fossarum.

    Science.gov (United States)

    Zubrod, J P; Baudy, P; Schulz, R; Bundschuh, M

    2014-05-01

    Fungicides are frequently applied in agriculture and are subsequently detected in surface waters in total concentrations of up to several tens of micrograms per liter. These concentrations imply potential effects on aquatic communities and fundamental ecosystem functions such as leaf litter breakdown. In this context, the present study investigates sublethal and lethal effects of organic (azoxystrobin, carbendazim, cyprodinil, quinoxyfen, and tebuconazole) and inorganic (three copper (Cu)-based substances and sulfur) current-use fungicides and their mixtures on the key leaf-shredding invertebrate Gammarus fossarum. The feeding activity of fungicide-exposed gammarids was quantified as sublethal endpoint using a static (organic fungicides; 7 d test duration) or a semi-static (inorganic fungicides; 6 d test duration with a water exchange after 3 d) approach (n=30). EC50-values of organic fungicides were generally observed at concentrations resulting in less than 20% mortality, with the exception of carbendazim. With regard to feeding, quinoxyfen was the most toxic organic fungicide, followed by cyprodinil, carbendazim, azoxystrobin, and tebuconazole. Although all tested organic fungicides have dissimilar (intended) modes of action, a mixture experiment revealed a synergistic effect on gammarids' feeding at high concentrations when using "independent action" as the reference model (∼35% deviation between predicted and observed effect). This may be explained by the presence of a synergizing azole fungicide (i.e. tebuconazole) in this mixture. Furthermore, lethal concentrations of all Cu-based fungicides assessed in this study were comparable amongst one another. However, they differed markedly in their effective concentrations when using feeding activity as the endpoint, with Cu-sulfate being most toxic, followed by Cu-hydroxide and Cu-octanoate. In contrast, sulfur neither affected survival nor the feeding activity of gammarids (up to ∼5 mg/L) but reduced Cu

  6. Influence of local habitat features on disease avoidance by Caribbean spiny lobsters in a casita-enhanced bay.

    Science.gov (United States)

    Briones-Fourzán, Patricia; Candia-Zulbarán, Rebeca I; Negrete-Soto, Fernando; Barradas-Ortiz, Cecilia; Huchin-Mian, Juan P; Lozano-Álvarez, Enrique

    2012-08-27

    In Bahía de la Ascensión, Mexico, 'casitas' (large artificial shelters) are extensively used to harvest Caribbean spiny lobsters Panulirus argus. After the discovery of a pathogenic virus, Panulirus argus virus 1 (PaV1), in these lobsters, laboratory experiments revealed that PaV1 could be transmitted by contact and through water, and that lobsters avoided shelters harboring diseased conspecifics. To examine these issues in the context of casitas, which typically harbor multiple lobsters of all sizes, we examined the distribution and aggregation patterns of lobsters in the absence/presence of diseased conspecifics (i.e. visibly infected with PaV1) in 531 casitas distributed over 3 bay zones, 1 poorly vegetated ('Vigía Chico', average depth: 1.5 m) and 2 more extensively vegetated ('Punta Allen': 2.5 m; 'Los Cayos': 2.4 m). All zones had relatively high indices of predation risk. Using several statistical approaches, we found that distribution parameters of lobsters were generally not affected by the presence of diseased conspecifics in casitas. Interestingly, however, in the shallower and less vegetated zone (Vigía Chico), individual casitas harbored more lobsters and lobsters were actually more crowded in casitas containing diseased conspecifics, yet disease prevalence was the lowest in lobsters of all sizes. These results suggest that (1) investment in disease avoidance by lobsters is partially modulated by local habitat features, (2) contact transmission rates of PaV1 may be lower in nature than in the laboratory, and (3) water-borne transmission rates may be lower in shallow, poorly vegetated habitats more exposed to solar ultraviolet radiation, which can damage viral particles.

  7. Characterising the fate of nitrogenous waste from the sea-cage aquaculture of spiny lobsters using numerical modelling.

    Science.gov (United States)

    Lee, Soxi; Hartstein, Neil D; Jeffs, Andrew

    2015-06-01

    Although the aquaculture of spiny lobsters has been expanding since the 1970s, very little is known about the potential environmental impacts on water quality of this activity. This study quantified the production of dissolved inorganic nitrogen (DIN) from Australasian red spiny lobsters, Jasus edwardsii, in the laboratory, and these data were then used in a numerical model to predict the dispersal pattern of DIN from a hypothetical commercial spiny lobster farm for a coastal site where such a farm would typically be located. Modelling scenarios were set up with combinations of two different stocking densities (3 and 5 kg m(-3)), two different diets (mussels and moist artificial diet) and three different feed conversion ratios (FCR = 3, 5 and 28). DIN excretion rate from unfed lobsters in the laboratory on average was 1.10 ± 0.12 μg N g(-1) h(-1) while feeding lobsters on mussels and artificial diet increased DIN excretion significantly by around eightfold and twofold, respectively. Ammonia was consistently the dominant contributor to measured DIN output from lobsters. Modelling results indicated that the mean elevated DIN from a hypothetical farm where the lobsters were fed with mussels ranged from 7 up to 20 μg N L(-1) with increasing stocking density and FCR and was 30-150 % higher than the mean elevated DIN resulting from lobsters fed with artificial diet. Overall, the results indicated that DIN output from the hypothetical spiny lobster sea-cage farming is unlikely to be problematic using the FCR, stocking density, and the number of cages modelled at the coastal site in this study. Furthermore, feeding lobsters with artificial diet can help maintain a lower DIN output than seafood, such as mussels or trash fish.

  8. Fishing for lobsters indirectly increases epidemics in sea urchins

    Science.gov (United States)

    Lafferty, Kevin D.

    2004-01-01

    Two ecological paradigms, the trophic cascade and the host-density threshold in disease, interact in the kelp-forest ecosystem to structure the community. To investigate what happens when a trophic cascade pushes a host population over a host-threshold density, I analyzed a 20-year data set of kelp forest communities at 16 sites in the region of the Channel Islands National Park, California, USA. Historically, lobsters, and perhaps other predators, kept urchin populations at low levels and kelp forests developed a community-level trophic cascade. In geographic areas where the main predators on urchins were fished, urchin populations increased to the extent that they overgrazed algae and starvation eventually limited urchin-population growth. Despite the limitation of urchin population size by food availability, urchin densities, at times, well exceeded the host-density threshold for epidemics. An urchin-specific bacterial disease entered the region after 1992 and acted as a density-dependent mortality source. Dense populations were more likely to experience epidemics and suffer higher mortality. Disease did not reduce the urchin population at a site to the density that predators previously did. Therefore, disease did not fully replace predators in the trophic cascade. These results indicate how fishing top predators can indirectly favor disease transmission in prey populations.

  9. STUDI MEMBRAN KITOSAN DARI KULIT LOBSTER BAMBU SEBAGAI MEMBRAN FILTRASI

    Directory of Open Access Journals (Sweden)

    Ni Nyoman Putri Windari

    2016-02-01

    Full Text Available The study of the extraction and characterization of chitosan from skin waste of Bamboo Lobster (Panulirus versicolor has been done. Chitosan is extracted using conventional method, namely the initial process: cleaning and drying (pretreatment, demineralization, deproteination, and deacetylation. The chitosan obtained has been used to prepare chitosan membrane 2% with acetic acid 1% as solvent. The membrane prepared by phase inversion method withprecipitation through solvent evaporation. The prepared membranes were characterized by FTIR spectrophotometer, Nova 1200e by BJH method and filtration method. The results obtained that degree of deacetylation (DD of chitosan is 70.016%. The thickness of the membrane is 0.361 mm. The FTIR spectra show that functional groups obtained are -NH, -CH, C=O, C-O and -CN. From BJH method obtained that the pore radius is 1.69 nm and pore density is 8.95 x 105pores/m3. From the filtration method obtained that at each pressure, 80-85 kPa and 90-100 kPa, the PWF values are 381.232 and 454.545 L/m2.h, respectively.

  10. MC ray-tracing optimization of lobster-eye focusing devices with RESTRAX

    International Nuclear Information System (INIS)

    Saroun, Jan; Kulda, Jiri

    2006-01-01

    The enhanced functionalities of the latest version of the RESTRAX software, providing a high-speed Monte Carlo (MC) ray-tracing code to represent a virtual three-axis neutron spectrometer, include representation of parabolic and elliptic guide profiles and facilities for numerical optimization of parameter values, characterizing the instrument components. As examples, we present simulations of a doubly focusing monochromator in combination with cold neutron guides and lobster-eye supermirror devices, concentrating a monochromatic beam to small sample volumes. A Levenberg-Marquardt minimization algorithm is used to optimize simultaneously several parameters of the monochromator and lobster-eye guides. We compare the performance of optimized configurations in terms of monochromatic neutron flux and energy spread and demonstrate the effect of lobster-eye optics on beam transformations in real and momentum subspaces

  11. Source and specificity of chemical cues mediating shelter preference of Caribbean spiny lobsters (Panulirus argus).

    Science.gov (United States)

    Horner, Amy J; Nickles, Scott P; Weissburg, Marc J; Derby, Charles D

    2006-10-01

    Caribbean spiny lobsters display a diversity of social behaviors, one of the most prevalent of which is gregarious diurnal sheltering. Previous research has demonstrated that shelter selection is chemically mediated, but the source of release and the identity of the aggregation signal are unknown. In this study, we investigated the source and specificity of the aggregation signal in Caribbean spiny lobsters, Panulirus argus. We developed a relatively rapid test of shelter choice in a 5000-l laboratory flume that simulated flow conditions in the spiny lobster's natural environment, and used it to examine the shelter preference of the animals in response to a variety of odorants. We found that both males and females associated preferentially with shelters emanating conspecific urine of either sex, but not with shelters emanating seawater, food odors, or the scent of a predatory octopus. These results demonstrate specificity in the cues mediating sheltering behavior and show that urine is at least one source of the aggregation signal.

  12. Lobster eye X-ray optics: Data processing from two 1D modules

    Science.gov (United States)

    Nentvich, O.; Urban, M.; Stehlikova, V.; Sieger, L.; Hudec, R.

    2017-07-01

    The X-ray imaging is usually done by Wolter I telescopes. They are suitable for imaging of a small part of the sky, not for all-sky monitoring. This monitoring could be done by a Lobster eye optics which can theoretically have a field of view up to 360 deg. All sky monitoring system enables a quick identification of source and its direction. This paper describes the possibility of using two independent one-dimensional Lobster Eye modules for this purpose instead of Wolter I and their post-processing into an 2D image. This arrangement allows scanning with less energy loss compared to Wolter I or two-dimensional Lobster Eye optics. It is most suitable especially for very weak sources.

  13. Improving the effectiveness of escape windows in directed Norway lobster Nephrops norvegicus trawl fisheries

    DEFF Research Database (Denmark)

    Madsen, Niels; Holst, René; Frandsen, Rikke

    2012-01-01

    A substantial improvement in the bycatch selectivity of Norway lobster Nephrops norvegicus trawls is required, particularly with respect to cod Gadus morhua , whose stocks are at low levels in several areas. Conventional escape windows are not adequate to properly release cod and other bycatch...... species caught in the trawls. To address this issue, we developed a novel sorting box concept consisting of a four-panel section with a window on the top in order to improve the escape of cod and other bycatch species through an escape window while retaining the target catch of Norway lobster. The concept....... The reduction in bycatch decreased with decreasing mesh size and increasing height of the sorting box. Escape of Norway lobster through the escape window was limited. A modified version of the sorting box concept was implemented in the Kattegat fishery from 2009 onwards...

  14. Development and test of selective sorting grids used in the Norway lobster (Nephrops norvegicus) fishery

    DEFF Research Database (Denmark)

    Madsen, Niels; Holst, René; Frandsen, Rikke

    2017-01-01

    Due to generally high discard rates in Norway lobster (Nephrops norvegicus) fisheries, a discard ban coming up and to the cod recovery plan in several areas, selective sorting grids have been tested in many areas and are specified by legislation for use in the Kattegat and Skagerrak area bordering...... Norway, Denmark and Sweden. Grids are very selective, but they can lead to loss of landable Norway lobster and valuable fish species. To improve retention of these species, we developed three new grids using made by polyurethane to make them flexible: One grid had horizontal bars, one had vertical bars....... More flatfish passed the grid with horizontal bars compared to that with vertical bars, but the retention rate was still low. Use of the guiding funnel increased the contact with the grid considerably for both target and unwanted species. In all three grid designs, there were losses of Norway lobster...

  15. Ocean observing systems support operational forecasts for the timing of Maine's lobster fishery

    Science.gov (United States)

    Mills, K.; Hernandez, C.; Pershing, A. J.

    2016-02-01

    American lobster supports one of the most valuable fisheries in the United States, with a landed value in 2013 exceeding $460M. Although US lobstermen are free to fish throughout the year, the New England climate, lobster biology and fleet dynamics lead to a strong annual cycle with catch rates rising rapidly in early summer and landings peaking in late summer. When this annual cycle is disrupted, it can impact the supply and ultimately the price of lobsters. During the record warm conditions in 2012, the rise in catch rates occurred three weeks ahead of normal. Combined with higher than normal landings from the spring Canadian fishery, the early and high volume landings in 2012 led to a collapse in price that severely stressed the U. S. fishery, especially in Maine where over 85% of the landings occur. Based on this experience, we have been developing seasonal forecasts of the phenology of Maine lobster landings. Using temperatures at 50m from four NERACOOS buoys in the Gulf of Maine, we can reliably forecast the date when the Maine lobster fishery will `turn on' for the year, with prediction accuracy peaking in April. The high-landings period normally starts in July, and the 2-3 month lead-time provides some advance warning to dealers and processors of when their capacity needs to be ready and to fishermen of potential supply chain and market impacts such as we observed in 2012. We are currently working towards finer-scale regional forecasts along the Maine coast that may include other features that will provide information to help the lobster industry adapt to the rapid changes that are underway in the Gulf of Maine.

  16. Additional slipper lobsters of the subfamily Scyllarinae Latreille, 1825 (Crustacea, Achelata, Scyllaridae) from Taiwan.

    Science.gov (United States)

    Yang, Chien-Hui; Lin, Chia-Wei; Chan, Tin-Yam

    2014-08-15

    Five scyllarine lobsters are recorded from Taiwan for the first time. They are Bathyarctus rubens (Alcock & Anderson, 1894), Biarctus sordidus (Stimpson, 1860), Chelarctus aureus (Holthuis, 1963), Crenarctus bicuspidatus (De Man, 1905) and Petrarctus veliger Holthuis, 2002. The distributions of B. rubens, C. aureus and P. veliger are extended northwards to Taiwan. Distinguishing characters of these five species are illustrated and color photographs of all but B. sordidus are provided. Altogether, nine genera and 17 species of scyllarine lobsters are now known from Taiwan. 

  17. Development and testing of a separator frame in a Norway lobster Nephrops norvegicus fishery

    DEFF Research Database (Denmark)

    Madsen, Niels; Holst, René

    2017-01-01

    Norway lobster Nephrops norvegicus fisheries are often characterized by high bycatch and discard rates. However, fisheries species exhibit differences in vertical behaviour that can be used to develop selective devices. We developed a separator frame that can be inserted into the forward part...... the separator frame and ending up in the bottom cod-end, the top cod-end, or penetrating the window. The majority of Norway lobster and flatfish entered the bottom cod-end, and most gadoids entered the top cod-end. A relatively high proportion of gadoids and flatfish that entered the top cod-end penetrated...

  18. Consequences of lower food intake on the digestive enzymes activities, the energy reserves and the reproductive outcome in Gammarus fossarum.

    Directory of Open Access Journals (Sweden)

    Laetitia Charron

    Full Text Available Digestive enzyme activity is often used as a sensitive response to environmental pollution. However, only little is known about the negative effects of stress on digestive capacities and their consequences on energy reserves and reproduction, although these parameters are important for the maintenance of populations. To highlight if changes in biochemical responses (digestive enzymes and reserves led to impairments at an individual level (fertility, Gammarus fossarum were submitted to a lower food intake throughout a complete female reproductive cycle (i.e. from ovogenesis to offspring production. For both males and females, amylase activity was inhibited by the diet stress, whereas trypsin activity was not influenced. These results underline similar sensitivity of males and females concerning their digestive capacity. Energy reserves decreased with food starvation in females, and remained stable in males. The number of embryos per female decreased with food starvation. Lower digestive activity in males and females therefore appears as an early response. These results underline the ecological relevance of digestive markers, as they make it possible to anticipate upcoming consequences on reproduction in females, a key biological variable for population dynamics.

  19. Effects of endosulfan, thiamethoxam, and indoxacarb in combination with atrazine on multi-biomarkers in Gammarus kischineffensis.

    Science.gov (United States)

    Demirci, Özlem; Güven, Kemal; Asma, Dilek; Öğüt, Serdal; Uğurlu, Pelin

    2018-01-01

    Studies addressing the toxicity of pesticides towards non-target organisms focus on the median lethal concentration and biochemical response of individual pesticides. However, when determining environmental risks, it is important to test the combined effects of pesticides, such as insecticides and herbicides, which are frequently used together in agricultural areas. Here we aimed to investigate the toxic effects of the combined use of the herbicide atrazine and the insecticides, endosulfan, indoxacarb, and thiamethoxam on Gammarus kischineffensis. To do this, we tested the activities of oxidative stress, detoxification, and neurotoxicity biomarkers. Compared to atrazine alone, we detected higher glutathione-S-transferase, catalase and superoxide dismutase activities (oxidative stress biomarkers) when atrazine was combined with either endosulfan or indoxacarb. However, higher IBR values were determined in organisms where pesticide mixtures were used according to individual use. Based on these results, mixtures of atrazine and other pesticides may cause synergistic effects and may be evidence of increased toxicity and oxidative stress. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Differential susceptibility of horizontal and vertical swimming activity to cadmium exposure in a gammaridean amphipod (Gammarus lawrencianus)

    International Nuclear Information System (INIS)

    Wallace, W.G.; Estephan, A.

    2004-01-01

    In this study two indices of swimming behavior (horizontal and vertical swimming activity) in a gammaridean amphipod (Gammarus lawrencianus) were examined for their sensitivity to Cd exposure. G. lawrencianus were exposed for 72 h to a variety of Cd concentrations [background (∼12), 62, 125, 250 and 500 μg l -1 ] at 20 ppt. Subsequent to exposure, video surveillance of survivors held within grooved rings or clear boxes was used to assess horizontal swimming activity (percentage of time mobile) and vertical swimming activity (number of surfacings), respectively. Results show that control amphipods were quite active, being mobile ∼61% of the time, with horizontal swimming activity decreasing (P -1 . Vertical swimming activity in amphipods was also impacted by Cd exposure (P -1 ) and 62 μg l -1 (60 versus ∼26 surfacings, respectively), which is approximately four-fold lower than the estimated 72 h LC 50 (250 μg l -1 ) for G. lawrencianus. Based on fluid dynamic considerations, it is speculated that of the two behaviors, vertical swimming activity is more sensitive to Cd exposure because of the presumed greater energetic costs associated with producing enough thrust to attain the lift required to make a vertical ascent into the water

  1. Suspended particles only marginally reduce pyrethroid toxicity to the freshwater invertebrate Gammarus pulex (L.) during pulse exposure.

    Science.gov (United States)

    Rasmussen, Jes Jessen; Cedergreen, Nina; Kronvang, Brian; Andersen, Maj-Britt Bjergager; Nørum, Ulrik; Kretschmann, Andreas; Strobel, Bjarne Westergaard; Hansen, Hans Christian Bruun

    2016-04-01

    Current ecotoxicological research on particle-associated pyrethroids in freshwater systems focuses almost exclusively on sediment-exposure scenarios and sediment-dwelling macroinvertebrates. We studied how suspended particles influence acute effects of lambda-cyhalothrin and bifenthrin on the epibenthic freshwater amphipod Gammarus pulex (L.) using brief pulse exposures followed by a 144 h post exposure recovery phase. Humic acid (HA) and the clay mineral montmorillonite (MM) were used as model sorbents in environmentally realistic concentrations (5, 25 and 125 mg L(-1)). Mortality of G. pulex was recorded during the post exposure recovery phase and locomotor behavior was measured during exposure to lambda-cyhalothrin. We found that HA in concentrations ≥25 mg L(-1) adsorbed the majority of pyrethroids but only reduced mortality of G. pulex up to a factor of four compared to pyrethroid-only treatments. MM suspensions adsorbed a variable fraction of pyrethroids (10% for bifenthrin and 70% for lambda-cyhalothrin) but did not significantly change the concentration-response relationship compared to pure pyrethroid treatments. Behavioral responses and immobilisation rate of G. pulex were reduced in the presence of HA, whereas behavioral responses and immobilisation rate were increased in the presence of MM. This indicates that G. pulex was capable of sensing the bioavailable fraction of lambda-cyhalothrin. Our results imply that suspended particles reduce to only a limited extent the toxicity of pyrethroids to G. pulex and that passive uptake of pyrethroids can be significant even when pyrethroids are adsorbed to suspended particles.

  2. Antioxidant responses in the polar marine sea-ice amphipod Gammarus wilkitzkii to natural and experimentally increased UV levels

    International Nuclear Information System (INIS)

    Krapp, Rupert H.; Bassinet, Thievery; Berge, Jorgen; Pampanin, Daniela M.; Camus, Lionel

    2009-01-01

    Polar marine surface waters are characterized by high levels of dissolved oxygen, seasonally intense UV irradiance and high levels of dissolved organic carbon. Therefore, the Arctic sea-ice habitat is regarded as a strongly pro-oxidant environment, even though its significant ice cover protects the ice-associated (=sympagic) fauna from direct irradiation to a large extent. In order to investigate the level of resistance to oxyradical stress, we sampled the sympagic amphipod species Gammarus wilkitzkii during both winter and summer conditions, as well as exposed specimens to simulated levels of near-natural and elevated levels of UV irradiation. Results showed that this amphipod species possessed a much stronger antioxidant capacity during summer than during winter. Also, the experimental UV exposure showed a depletion in antioxidant defences, indicating a negative effect of UV exposure on the total oxyradical scavenging capacity. Another sympagic organism, Onisimus nanseni, was sampled during summer conditions. When compared to G. wilkitzkii, the species showed even higher antioxidant scavenging capacity.

  3. A lobster-eye on the x-ray sky

    International Nuclear Information System (INIS)

    Peele, A. G.; Zhang, W.; Gendreau, K. C.; Petre, R.; White, N. E.

    1999-01-01

    We propose an x-ray all-sky monitor for the International Space Station (ISS) that will be ten times more sensitive than past monitors and that opens up a new band of the soft x-ray spectrum (0.1 -3.0 keV) for study. Taking advantage of the power telemetry and space available on the ISS we can use a telescope geometry and detectors that will provide better than 4 arc minute resolution of the entire sky in a 1.5 hr duty cycle. To achieve this sensitivity and resolution we use focusing optics based on the lobster-eye geometry. We propose two approaches to the construction of the optics. The first method, well within the reach of existing technology, is to approximate the lobster-eye geometry by building crossed arrays of planar reflectors, this gives great control over the reflecting surface but is limited in terms of resolution at the baseline 4 arc minute level. The second method is to use microchannel plates: this technology has the potential to greatly exceed the baseline resolution and sensitivity but is yet to be fully demonstrated. A simultaneous development of both approaches with selection of the superior candidate at the end of the development phase is suggested. The instrument is made of a number of modules based on a 2x2 cooled CCD detector array that covers an area of 6x6 cm 2 at the focal plane. Using optics with a radius of curvature of 0.75 m this gives each module a field of view of 9 deg. x 9 deg. The modular approach gives us enormous flexibility in terms of physical arrangement on the ISS so that we may take advantage of clear lines of sight and also in terms of built-in redundancy. We estimate that ∼50 such modules give us instantaneous coverage of 1/10 of the sky. The scientific case for this mission is almost too broad to state here. The instrument we describe will allow investigation of the long term light curves of thousands of AGN, it will detect thousands of transients, including GRBs and type II supernova, and the stellar coronae of

  4. West Coast rock lobster Jasus lalandii are dis- tributed from about ...

    African Journals Online (AJOL)

    spamer

    and a ban on the retention of lobster in a soft shell state or ... However, a diver operating from shore could also collect ... The permit system was discontinued during 1986 ... person's place of residence at any one time was re- ..... real situation.

  5. After an initial, localized decline in rock lobster Jasus lalandii growth ...

    African Journals Online (AJOL)

    spamer

    Pacific Ocean. In the southern Benguela, the most obvious signature of this ENSO was the reduced fre- quency and intensity of southerly, upwelling-inducing winds, with a concomitant increase in westerly winds. This study attempts to relate the reduction in lobster growth and productivity to environmental factors which.

  6. A novel image processing method to determine the nutritional condition of lobsters.

    Science.gov (United States)

    Berillis, P; Simon, C; Mente, E; Sofos, F; Karapanagiotidis, I T

    2013-02-01

    The digestive gland of crustacean is involved in various metabolic activities, including the synthesis and secretion of digestive enzymes that begin the process of food digestion, intracellular digestion and absorption of nutrients, storage of reserves, and disposal of waste products. It consists of two glandular lobes which extensively subdivide to form a complex of blind-ending tubules, whose size, surface area, and digestive cells are associated with intracellular digestion and the nutritional status of the organism. The aim of this paper was to study the morphology of the digestive gland in various lobster species and calculate the surface area of tubules, lumen and digestive cells (R-, F-, and B-cells) and their ratios to total tubule surface area. The similarity in ratios obtained in this study between individual lobsters suggests that the method developed in this study can be successfully applied to a range of species. This study describes a novel image processing algorithm for the automatic measurement of the hepatopancreas structure using stained cross sections of digestive gland tubules. The proposed new methodology could be used for studying the physiology and nutrient metabolism of lobsters and other crustaceans. The computer-aided analysis described in this paper is accurate for the quantitative assessment of the lobster's digestive gland structure. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Assessment of predation risk through conspecific alarm odors by spiny lobsters

    Science.gov (United States)

    2009-01-01

    Strong “alarm odors” emanating from lethally injured conspecifics may indicate an imminent risk of predation to spiny lobsters. In laboratory trials,1 strong conspecific alarm odors elicited avoidance in Panulirus argus, a highly gregarious species that displays collective defense behavior, but not in Panulirus guttatus, a species that tends to aggregate when reproductive activity is high (spring) but not when it is low (late summer) and does not display collective defensive behavior. To reduce predation risk, however, lobsters may autotomize limbs, thus sustaining nonlethal injuries. I tested the response of these lobsters to scents emanating from intact, lethally-injured and non-lethally injured conspecifics. In P. argus, these scents elicited, respectively, attraction, avoidance and a random response, suggesting that, in P. argus, avoidance of conspecific alarm odors depends on their strength. In contrast, P. guttatus lobsters responded at random to scents of lethally injured conspecifics and showed a similar response to scents of intact and non-lethally injured conspecifics in the spring (attraction) and in the summer (random), reflecting the more cryptic defensive behavior of this species. Therefore, both species use conspecific alarm odors for risk-assessment, but each responds to these cues in the most effective way to reduce its risk of predation. PMID:19721871

  8. Finestkind: The American Lobster. A Learning Experience for Marine Education. Northern New England Marine Education Project.

    Science.gov (United States)

    Maine Univ., Orono. Coll. of Education.

    This interdisciplinary unit is intended for use in the fourth grade. Through discussion of the American Lobster, its economics, history, literature, and biology, the unit describes the effects of the marine environment on human history and culture. Sections deal with how marine organisms have evolved. Detailed descriptions are provided of lobster…

  9. Assessment of predation risk through conspecific alarm odors by spiny lobsters: How much is too much?

    Science.gov (United States)

    Briones-Fourzán, Patricia

    2009-07-01

    Strong "alarm odors" emanating from lethally injured conspecifics may indicate an imminent risk of predation to spiny lobsters. In laboratory trials,1 strong conspecific alarm odors elicited avoidance in Panulirus argus, a highly gregarious species that displays collective defense behavior, but not in Panulirus guttatus, a species that tends to aggregate when reproductive activity is high (spring) but not when it is low (late summer) and does not display collective defensive behavior. To reduce predation risk, however, lobsters may autotomize limbs, thus sustaining nonlethal injuries. I tested the response of these lobsters to scents emanating from intact, lethally-injured and non-lethally injured conspecifics. In P. argus, these scents elicited, respectively, attraction, avoidance and a random response, suggesting that, in P. argus, avoidance of conspecific alarm odors depends on their strength. In contrast, P. guttatus lobsters responded at random to scents of lethally injured conspecifics and showed a similar response to scents of intact and non-lethally injured conspecifics in the spring (attraction) and in the summer (random), reflecting the more cryptic defensive behavior of this species. Therefore, both species use conspecific alarm odors for risk-assessment, but each responds to these cues in the most effective way to reduce its risk of predation.

  10. THE MORPHOLOGICAL BASIS FOR OLFACTORY PERCEPTION OF STEROIDS DUING AGONISTIC BEHAVIOR IN LOBSTER: PRELIMINARY EXPERIMENTS

    Science.gov (United States)

    The morphological basis for olfactory perception of steroids during agonistic behavior in lobsters: preliminary experiments. Borsay Horowitz, DJ1, Kass-Simon, G2, Coglianese, D2, Martin, L2, Boseman, M2, Cromarty, S3, Randall, K3, Fini, A.3 1US EPA, NHEERL, ORD, Atlantic Ecology...

  11. Diet of the west coast rock lobster Jasus Lalandii : Influence of ...

    African Journals Online (AJOL)

    The diet of small lobsters (<75mm CL) consisted of a wide range of species, which included, in order of importance, coralline algae, barnacles Notomegabalanus algicola, sponges and ribbed mussels Aulacomya ater. However, prey items rich in inorganic material were not dominant in their diet, as had been predicted.

  12. Novel optics for conditioning neutron beams. II Focussing neutrons with a 'lobster-eye' optic

    International Nuclear Information System (INIS)

    Allman, B.E.; Cimmino, A.; Griffin, S.L.; Klein, A.G.; Nugent, K.A.

    1998-01-01

    Square-channel capillary, or 'Lobster-eye' arrays have been shown to be the optimum geometry for array optics. This configuration leads to a novel class of conditioning devices for X-ray and neutron beams. We present the first results of the focussing of neutrons with a Pb glass square-channel array. (authors)

  13. 33 CFR 100.109 - Winter Harbor Lobster Boat Race, Winter Harbor, ME.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Winter Harbor Lobster Boat Race, Winter Harbor, ME. 100.109 Section 100.109 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.109 Winter Harbor...

  14. The deep-water spiny lobster Palinurus gilchristi is one of five ...

    African Journals Online (AJOL)

    spamer

    The deep-water spiny lobster Palinurus gilchristi is one of five ... conditions because all features that can be used to determine the ... growth as a function of CL were calculated for each ..... (>85 mm CL) may bear eggs more than once per year.

  15. Microbiological aspects of phyllosoma rearing of the ornate rock lobster Panulirus ornatus

    DEFF Research Database (Denmark)

    Bourne, D.; Webster, N.; Payne, Matthew

    2007-01-01

    Rock lobsters of the Palinuridae are the most valuable wild fisheries sector in Australia and are currently target aquaculture species. Significant challenges exist however to produce commercial scale quantities of post-larvae due to an extended larval phase which acerbates a high rate of larval...

  16. Development of new concepts for escape windows to minimise cod catches in Norway lobster fisheries

    DEFF Research Database (Denmark)

    Madsen, Niels; Frandsen, Rikke; Holst, René

    2010-01-01

    Gear selectivity with regard to cod (Gadus morhua) needs to be improved in the Kattegat and Skagerrak Norway lobster (Nephrops norvegicus) fishery. One way to achieve this goal is to improve the selectivity of an escape window (henceforth window) in the gear. Our gear development focused particul......Gear selectivity with regard to cod (Gadus morhua) needs to be improved in the Kattegat and Skagerrak Norway lobster (Nephrops norvegicus) fishery. One way to achieve this goal is to improve the selectivity of an escape window (henceforth window) in the gear. Our gear development focused...... particularly on moving the window further back, gaining more stability in the codend to avoid loss of Norway lobster through the window, making a relatively narrow section where the window is located, and testing larger mesh sizes in the window. We designed a four panel sorting section—the sorting box......, but no improvement was observed for cod that came into contact with the window after reducing the distance from the window to the codline. The sorting box also showed a high reduction of flatfish and other roundfish species. The retention of Norway lobster above minimum landing size in the sorting box was higher...

  17. Adaptive behaviour of fishers to external perturbations: simulation of the Tasmanian rock lobster fishery

    NARCIS (Netherlands)

    Hamon, K.G.; Frusher, S.D.; Little, L.R.; Thebaud, O.; Punt, A.E.

    2014-01-01

    The rock lobster, Jasus edwardsii, lies on a global "hotspot" for climate change in the southeastern Australian state of Tasmania. The short-term effects of climate change are predicted to lead to an increasing exploitable biomass in the south and declining biomass in the north of the state. The

  18. Alternative supplementary biochemic food for growing up the fresh water lobster (Cherax quadricarinatus

    Directory of Open Access Journals (Sweden)

    PRABANG SETYONO

    2009-11-01

    Full Text Available Priyono E, Astirin OP, Setyono P. 2009. Alternative supplementary biochemic food for growing up the fresh water lobster (Cherax quadricarinatus. Nusantara Bioscience 1: 123-130. This research denotes to know the influence of biochemic composition to the rapid grow of fresh water lobster on the stadium of post larva (PL of 60 within three months. This research used the complete random planning dealing with 4 treatments and each treatment would get 3 times cycle. The treatments cover, group K tested animal was treted with 100% mill food containing 30% of protein. Group A is given with food and biochemic food containing 13,34% of protein. Group B is the treated with mill food which is mixed with biochemic food containing 10,7% of protein. While group C was tested by treating them with mill food and biochemic food containing 13,58%. After all the above mentioned would be set up within 3:1 comparation. The variable of this research were the length of the abdomen, cephalothorax, total length, and the wet weight. The data analysis is using ANOVA system on 95% power test completed by of SPSS version 13. The result of the research shows that mentioned treatments give us the same influence toward the growth of fresh water lobster. The composition of biochemic food with the containing protein around 10,7%,13.34% and 13,38% has given the same effect to the lobster growth on post larva 60 level. There is strong correlation between abdomen and cephalothorax and between the total length and the lobsters weight.Key words: Cherax quadricarinatus, suplementary food, water quality.Abstrak. Priyono E, Astirin OP, Setyono P. 2009. Alternatif penambahan suplemen hayati untuk meningkatkan pertumbuhan udang lobster air tawar (Cherax quadricarinatus. Nusantara Bioscience 1: 123-130. Penelitian ini bertujuan untuk mengetahui pengaruh pemberian suplemen hayati sehingga dapat meningkatkan pertumbuhan lobster air tawar pada stadia post larva (PL 60 pada masa pertumbuhan 3

  19. Diversity of developmental patterns in achelate lobsters-today and in the Mesozoic.

    Science.gov (United States)

    Haug, Joachim T; Audo, Denis; Charbonnier, Sylvain; Haug, Carolin

    2013-11-01

    Modern achelate lobsters, slipper and spiny lobsters, have a specific post-embryonic developmental pattern with the following phases: phyllosoma, nisto (slipper lobsters) or puerulus (spiny lobsters), juvenile and adult. The phyllosoma is a peculiar larva, which transforms through a metamorphic moult into another larval form, the nisto or puerulus which largely resembles the juvenile. Unlike the nisto and puerulus, the phyllosoma is characterised by numerous morphological differences to the adult, e.g. a thin head shield, elongate appendages, exopods on these appendages and a special claw. Our reinvestigation of the 85 million years old fossil "Eryoneicus sahelalmae" demonstrates that it represents an unusual type of achelatan lobster larva, characterised by a mixture of phyllosoma and post-phyllosoma characters. We ascribe it to its own genus: Polzicaris nov. gen. We study its significance by comparisons with other cases of Mesozoic fossil larvae also characterised by a mixture of characters. Accordingly, all these larvae are interpreted as ontogenetic intermediates between phyllosoma and post-phyllosoma morphology. Remarkably, most of the larvae show a unique mixture of retained larval and already developed post-larval features. Considering the different-and incompatible-mixture of characters of each of these larvae and their wide geographical and temporal distribution, we interpret all these larvae as belonging to distinct species. The particular character combinations in the different larvae make it currently difficult to reconstruct an evolutionary scenario with a stepwise character acquisition. Yet, it can be concluded that a larger diversity of larval forms and developmental patterns occurred in Mesozoic than in modern faunas.

  20. Opportunistic Computing with Lobster: Lessons Learned from Scaling up to 25k Non-Dedicated Cores

    Science.gov (United States)

    Wolf, Matthias; Woodard, Anna; Li, Wenzhao; Hurtado Anampa, Kenyi; Yannakopoulos, Anna; Tovar, Benjamin; Donnelly, Patrick; Brenner, Paul; Lannon, Kevin; Hildreth, Mike; Thain, Douglas

    2017-10-01

    We previously described Lobster, a workflow management tool for exploiting volatile opportunistic computing resources for computation in HEP. We will discuss the various challenges that have been encountered while scaling up the simultaneous CPU core utilization and the software improvements required to overcome these challenges. Categories: Workflows can now be divided into categories based on their required system resources. This allows the batch queueing system to optimize assignment of tasks to nodes with the appropriate capabilities. Within each category, limits can be specified for the number of running jobs to regulate the utilization of communication bandwidth. System resource specifications for a task category can now be modified while a project is running, avoiding the need to restart the project if resource requirements differ from the initial estimates. Lobster now implements time limits on each task category to voluntarily terminate tasks. This allows partially completed work to be recovered. Workflow dependency specification: One workflow often requires data from other workflows as input. Rather than waiting for earlier workflows to be completed before beginning later ones, Lobster now allows dependent tasks to begin as soon as sufficient input data has accumulated. Resource monitoring: Lobster utilizes a new capability in Work Queue to monitor the system resources each task requires in order to identify bottlenecks and optimally assign tasks. The capability of the Lobster opportunistic workflow management system for HEP computation has been significantly increased. We have demonstrated efficient utilization of 25 000 non-dedicated cores and achieved a data input rate of 30 Gb/s and an output rate of 500GB/h. This has required new capabilities in task categorization, workflow dependency specification, and resource monitoring.

  1. Safety of the molluscicide Zequanox (R) to nontarget macroinvertebrates Gammarus lacustris (Amphipoda: Gammaridae) and Hexagenia spp. (Ephemeroptera: Ephemeridae)

    Science.gov (United States)

    Waller, Diane L.; Luoma, James A.; Erickson, Richard A.

    2016-01-01

    Zequanox® is a commercial formulation of the killed bacterium, Pseudomonas fluorescens (strain CL145A), that was developed to control dreissenid mussels. In 2014, Zequanox became the second product registered by the United States Environmental Protection Agency (USEPA) for use in open water environments as a molluscicide. Previous nontarget studies demonstrated the safety and selectivity of P. fluorescens CL154A, but the database on the toxicity of the formulation (Zequanox) is limited for macroinvertebrate taxa and exposure conditions. We evaluated the safety of Zequanox to the amphipod Gammarus lacustris lacustris, and nymphs of the burrowing mayfly, Hexagenia spp. at the maximum approved concentration (100 mg/L active ingredient, A.I.) and exposure duration (8 h). Survival of animals was assessed after 8 h of exposure and again at 24 and 96 h post-exposure. Histopathology of the digestive tract of control and treated animals was compared at 96 h post-exposure. The results showed no significant effect of Zequanox on survival of either species. Survival of G. lacustris exceeded 85% in all concentrations at all three sampling time points. Survival of Hexagenia spp. ranged from 71% (control) to 91% at 8 h, 89–93% at 24 h post-exposure, and 70–73% at 96 h post-exposure across all treatments. We saw no evidence of pathology in the visceral organs of treated animals. Our results indicate that application of Zequanox at the maximum approved concentration and exposure duration did not cause significant mortality or treatment-related histopathological changes to G. lacustris and Hexagenia spp.

  2. Claw asymmetry in lobsters: case study in developmental neuroethology.

    Science.gov (United States)

    Govind, C K

    1992-12-01

    An enduring debate in the study of development is the relative contribution of genetic and epigenetic factors in the genesis of an organism, that is, the nature vs. nurture debate. The behavior of the paired claws in the lobster offers promising material for pursuing this debate because of the way they develop. The paired claws and their closer muscles are initially symmetrical; both are slender in appearance and have a mixture of fast and slow fibers in their closer muscles. During a critical period of development, they become determined into a major (crusher) and minor (cutter) claw and during subsequent development acquire their final form and behavior: The crusher becomes a stout, molar-toothed claw capable of closing only slowly because its closer muscle has 100% slow fibers while the cutter becomes a slender, incisor-toothed claw capable of closing rapidly because its closer muscle has 90% fast fibers. Our initial hypothesis was that the more active claw became the crusher and its less active counterpart the cutter. Presumably, nerve activity would influence muscle transformation, which in turn would influence the exoskeleton to which they attach and hence claw morphology. Curtailing nerve activity to the claw prevented crusher development, while reflex activation of a claw promoted its development; both results support the notion that nerve activity directly regulates claw form and function. This is not, however, the case, for when both claws were reflexly exercised neither formed a crusher, signifying rather that bilateral differences in predominantly mechanoreceptive input to the paired claws somehow lateralized the claw ganglion [central nervous system (CNS)] into a crusher and cutter side. The side experiencing the greater activity becomes the crusher side while the contralateral side becomes the cutter and is also inhibited from ever becoming a crusher. This initial lateralization in the CNS is expressed, via as yet unknown pathways, at the periphery in

  3. Diet and nutrition of western rock lobsters, Panulirus cygnus, in shallow coastal waters: the role of habitat

    Science.gov (United States)

    Generalist consumers often have diets that vary considerably over time and space, which reflects changes in resource availability. Predicting diets of consumers can therefore be difficult. The western rock lobster, Panulirus cygnus, is an omnivorous generalist consumer that uses ...

  4. Characterization of the dominant bacterial communities during storage of Norway lobster and Norway lobster tails (Nephrops norvegicus) based on 16S rDNA analysis by PCR-DGGE.

    Science.gov (United States)

    Bekaert, Karen; Devriese, Lisa; Maes, Sara; Robbens, Johan

    2015-04-01

    The aim of this study was to investigate the microbial quality of whole Norway lobster (Nephrops norvegicus) and Norway lobster tails to optimize handling conditions. This was done by assessing the total viable count (TVC) and characterizing the dominant microbiota. The cultivable microorganisms were quantified via classical microbiological plating methods. To characterize as many bacterial species present as possible, we performed advanced molecular identification techniques (PCR-DGGE). The initial TVC of fresh Norway lobster meat was high (3.0 log cfu/g) as compared to fish. No significant difference between whole Norway lobster and Norway lobster tails could be found during the storage period. From day 6 of storage, a significant difference between Plate Count Agar (PCA) and Marine Agar (MA) was observed. The microbiota of Norway lobster was dominated by members of the Gram-negative genera such as Psychrobacter spp., Pseudoalteromonas spp., Pseudomonas spp., Luteimonas spp., and Aliivibrio spp. From these bacteria, mainly Psychrobacter spp. and Pseudomonas spp. remained present until the end of the storage period. These are known spoilage organisms in fishery products. Other known spoilage organisms of crustaceans such as Photobacterium spp. could not be identified. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. A marriage of convenience; a simple food chain comprised of Lemna minor (L.) and Gammarus pulex (L.) to study the dietary transfer of zinc.

    Science.gov (United States)

    Lahive, E; O'Halloran, J; Jansen, M A K

    2015-01-01

    Macrophytes contribute significantly to the cycling of metals in aquatic systems, through accumulation during growth and release during herbivory or decomposition. Accumulation of high levels of metals has been extensively documented in Lemnaceae (duckweeds). However, the degree of trophic transfer of metals from Lemnaceae to secondary consumers remains poorly understood. This study demonstrates that zinc accumulated in Lemna minor is bioavailable to the herbivore consumer Gammarus pulex. Overall, the higher the zinc content of L. minor, the more zinc accumulated in G. pulex. Accumulation in G. pulex was such that mortality occurred when they were fed high zinc-containing L. minor. Yet, the percentage of consumed zinc retained by G. pulex actually decreased with higher zinc concentrations in L. minor. We hypothesise that this decrease reflects internal zinc metabolism, including a shift from soluble to covalently bound zinc in high zinc-containing L. minor. Consistently, relatively more zinc is lost through depuration when G. pulex is fed L. minor with high zinc content. The developed Lemna-Gammarus system is simple, easily manipulated, and sensitive enough for changes in plant zinc metabolism to be reflected in metal accumulation by the herbivore, and therefore suitable to study ecologically relevant metal cycling in aquatic ecosystems. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  6. Additive effect of calcium depletion and low resource quality on Gammarus fossarum (Crustacea, Amphipoda) life history traits.

    Science.gov (United States)

    Rollin, Marc; Coulaud, Romain; Danger, Michael; Sohm, Bénédicte; Flayac, Justine; Bec, Alexandre; Chaumot, Arnaud; Geffard, Olivier; Felten, Vincent

    2018-04-01

    Gammarus fossarum is an often-abundant crustacean detritivore that contributes importantly to leaf litter breakdown in oligotrophic, mainly heterotrophic, headwater streams. This species requires large amounts of Ca to moult, thus allowing growth and reproduction. Because resource quality is tightly coupled to the organism's growth and physiological status, we hypothesised that low Ca concentration [Ca] and low food resource quality (low phosphorus [P] and/or reduced highly unsaturated fatty acid [HUFA] contents) would interactively impair molecular responses (gene expression) and reproduction of G. fossarum. To investigate the effects of food resources quality, we experimentally manipulated the P content of sycamore leaves and also used diatoms because they contain high amounts of HUFAs. Three resource quality treatments were tested: low quality (LQ, unmanipulated leaves: low P content), high quality 1 (HQ1; P-manipulated leaves: high P content), and high quality 2 (unmanipulated leaves supplemented with a pellet containing diatoms: high P and HUFA content). Naturally, demineralised stream water was supplemented with CaSO 4 to obtain three Ca concentrations (2, 3.5, and 10.5 mg Ca L -1 ). For 21 days, pairs of G. fossarum were individually exposed to one of the nine treatments (3 [Ca] × 3 resource qualities). At the individual level, strong and significant delays in moult stage were observed in gammarids exposed to lower [Ca] and to lower resource quality, with additive effects lengthening the duration of the reproductive cycle. Effects at the molecular level were investigated by measuring expression of 12 genes involved in energy production, translation, or Ca or P homeostasis. Expression of ATP synthase beta (higher in HQ2), calcified cuticle protein (higher in HQ1 and HQ2), and tropomyosin (higher in HQ2 compared to HQ1) was significantly affected by resource quality, and significant additive effects on Ca transporting ATPase expression were induced by

  7. Optical metrology for analysis of lobster-eye x-ray optics

    International Nuclear Information System (INIS)

    Irving, Thomas H.K.; Peele, Andrew G.; Nugent, Keith A.

    2003-01-01

    A new method that uses optical microscopy to determine the physical structure of lobster-eye x-ray optics is described. This approach offers the ability to predict x-ray performance without having to take an x-ray measurement. An overlapping series of images of the entrance and exit faces of an optic are obtained and examined by purpose-built software. A 24-parameter description of each channel is obtained from which a quantitative analysis of all the major optic defects, except surface roughness, is performed. Results for a planar lobster-eye optic are used to illustrate this technique and discuss its abilities as well as directions for future enhancements

  8. Tests of lobster eye optics for small space X-ray telescope

    International Nuclear Information System (INIS)

    Tichy, Vladimir; Barbera, Marco; Collura, Alfonso; Hromcik, Martin; Hudec, Rene; Inneman, Adolf; Jakubek, Jan; Marsik, Jiri; Marsikova, Veronika; Pina, Ladislav; Varisco, Salvatore

    2011-01-01

    The Lobster eye design for a grazing incidence X-ray optics provides wide field of view of the order of many degrees, for this reason it can be a convenient approach for the construction of space all-sky X-ray monitors. We present preliminary results of tests of prototype lobster eye X-ray optics in quasi parallel beam full imaging mode conducted using the 35 m long X-ray beam-line of INAF-OAPA in Palermo (Italy). X-ray images at the focal plane have been taken with a microchannel plate (MCP) detector at several energy values from 0.3 to 8 keV. The gain, the field of view and the angular resolution have been measured and compared with theoretical values.

  9. Electrophysiological Investigation of Different Methods of Anesthesia in Lobster and Crayfish

    Science.gov (United States)

    Fregin, Torsten; Bickmeyer, Ulf

    2016-01-01

    Objectives In search for methods of anesthesia of crustaceans, an implanted electrode into lobster and crayfish CNS enabled us to monitor signal propagation in the nerve system of animals undergoing different protocols. Results Cooling (tap water 0°C, sea water -1,8°C) and anesthesia with MgCl2 (10%) were both discarded as anesthetic procedures because responses to external stimuli were still detectable under treatment. Contrarily, bubbling the aquarium water with CO2 can be considered a “partially successful” anesthesia, because signal propagation is inhibited but before that the animals show discomfort. The procedure of “electro-stunning” induces epileptic-form seizures in the crustacean CNS (lobster, crayfish), which overlay but do not mitigate the response to external stimuli. After several minutes the activity declines before the nervous system starts to recover. A feasible way to sacrifice lobsters is to slowly raise the water temperature (1°C min-1), as all electrical activities in the CNS cease at temperatures above ~30°C, whereas below this temperature the animals do not show signs of stress or escape behavior (e.g. tail flips) in the warming water. Conclusion CO2 is efficient to anaesthetize lobster and crayfish but due to low pH in water is stressful to the animals previous to anesthesia. Electrical stunning induces epileptiform seizures but paralyses the animals and leads to a reversible decline of nerve system activity after seizure. Electric stunning or slowly warming just before preparation may meet ethical expectations regarding anaesthesia and to sacrifice crustaceans. PMID:27642755

  10. Genetic isolation between the Western and Eastern Pacific populations of pronghorn spiny lobster Panulirus penicillatus.

    Directory of Open Access Journals (Sweden)

    Seinen Chow

    Full Text Available The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142-1,207 bp and 16S rDNA (535-546 bp regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP(Galápagos Islands and its adjacent water, Central Pacific (CP(Hawaii and Tuamotu and the Western Pacific (WP(Japan, Indonesia, Fiji, New Caledonia and Australia. Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP. No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific, with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY.

  11. The Influence of Mark-Recapture Sampling Effort on Estimates of Rock Lobster Survival.

    Directory of Open Access Journals (Sweden)

    Ziya Kordjazi

    Full Text Available Five annual capture-mark-recapture surveys on Jasus edwardsii were used to evaluate the effect of sample size and fishing effort on the precision of estimated survival probability. Datasets of different numbers of individual lobsters (ranging from 200 to 1,000 lobsters were created by random subsampling from each annual survey. This process of random subsampling was also used to create 12 datasets of different levels of effort based on three levels of the number of traps (15, 30 and 50 traps per day and four levels of the number of sampling-days (2, 4, 6 and 7 days. The most parsimonious Cormack-Jolly-Seber (CJS model for estimating survival probability shifted from a constant model towards sex-dependent models with increasing sample size and effort. A sample of 500 lobsters or 50 traps used on four consecutive sampling-days was required for obtaining precise survival estimations for males and females, separately. Reduced sampling effort of 30 traps over four sampling days was sufficient if a survival estimate for both sexes combined was sufficient for management of the fishery.

  12. The Influence of Mark-Recapture Sampling Effort on Estimates of Rock Lobster Survival

    Science.gov (United States)

    Kordjazi, Ziya; Frusher, Stewart; Buxton, Colin; Gardner, Caleb; Bird, Tomas

    2016-01-01

    Five annual capture-mark-recapture surveys on Jasus edwardsii were used to evaluate the effect of sample size and fishing effort on the precision of estimated survival probability. Datasets of different numbers of individual lobsters (ranging from 200 to 1,000 lobsters) were created by random subsampling from each annual survey. This process of random subsampling was also used to create 12 datasets of different levels of effort based on three levels of the number of traps (15, 30 and 50 traps per day) and four levels of the number of sampling-days (2, 4, 6 and 7 days). The most parsimonious Cormack-Jolly-Seber (CJS) model for estimating survival probability shifted from a constant model towards sex-dependent models with increasing sample size and effort. A sample of 500 lobsters or 50 traps used on four consecutive sampling-days was required for obtaining precise survival estimations for males and females, separately. Reduced sampling effort of 30 traps over four sampling days was sufficient if a survival estimate for both sexes combined was sufficient for management of the fishery. PMID:26990561

  13. Artisanal fishing of spiny lobsters with gillnets — A significant anthropic impact on tropical reef ecosystem

    Directory of Open Access Journals (Sweden)

    Bruno Welter Giraldes

    2015-07-01

    Full Text Available Artisanal fishing activity with gillnets to capture the spiny lobster is a common practice along the coastal reefs of Brazil. This research aims to understand the impact that this artisanal fishing practice is having on the coastal reef systems analysing its associated fauna (bycatch and the stock of the target species Panulirus echinatus. The study compared an area which was subjected to intense gillnet fishing against one were the practice was absent. The analysis of target species using nocturnal visual census demonstrated a significantly higher number of P. echinatus at the site where gillnet use was virtually absent within three sampled habitats, fringe, cave and soft bottom. The analysis of bycatch species from artisanal fishermen’s gillnet landings recorded 4 lobster species and 10 crab species. These decapod species play an important ecological role as detritivores, herbivorous and first consumers within the reef ecosystem as well as being natural prey items for several reef fishes. The study concludes that this non-discriminatory fishing technique impacts directly on populations of P. echinatus, P. argus and P. laevicauda as well as other lobster and crab species which in-turn indirectly affects the ecological role of the tropical coastal reefs of Brazil.

  14. Characterization of X-ray Lobster Optics with a Hybrid CMOS sensor

    Science.gov (United States)

    Chattopadhyay, Tanmoy; Falcone, Abraham; Burrows, David N.; Bray, Evan; McQuaide, Maria; Kern, Matthew; Wages, Mitchell; Hull, Samuel; Inneman, Adolf; Hudec, Rene; Stehlikova, Veronika

    2018-01-01

    X-ray lobster optics provide a unique way to focus X-rays onto a small focal plane imager with wide field of view imaging. Such an instrument with angular resolution of a few arcminutes can be used to study GRB afterglows, as well as the variability and spectroscopic characteristics for various astrophysical objects. At Penn State University, we have characterized a lobster optic with an H1RG X-Ray hybrid CMOS detector (100 μm thick Silicon with 18 μm pixel size). The light-weight compact lobster optic with a 25 cm focal length provides two dimensional imaging with ~25 cm2 effective area at 2 keV. We utilize a 47 meter long X-ray beam line at Penn state University to do our experiments where we characterize the overall effective area of the instrument at 1.5 - 8 keV for both on-axis and off-axis angles. In this presentation, we will describe the characterization test stand and methods, as well as the detailed results. While this is simply a proof-of-concept experiment, such an instrument with significant collecting area can be explored for future rocket or CubeSat experiments.

  15. Changes in heart rate associated with contest outcome in agonistic encounters in lobsters.

    Science.gov (United States)

    Hernáindez-Falcón, Jesús; Basu, Alo C; Govindasamy, Siddhartan; Kravitz, Edward A

    2005-03-01

    Agonistic contests between lobsters housed together in a confined space progress through encounters of increasing intensity until a dominance relationship is established. Once this relationship is established, losing animals continually retreat from the advances of winners. These encounters are likely to consume much energy in both winning and losing animals. Therefore, one might expect involvement of many physiological systems before, during and after fights. Here, we report effects of agonistic encounters on cardiac frequency in winning and losing adult lobsters involved in dyadic interactions. The results show that: (i) small but significant increases in heart rate are observed upon chemical detection of a conspecific; (ii) during agonistic interactions, further increases in heart rate are seen; and (iii) ultimate winners exhibit greater increases in heart rate lasting longer periods of time compared to ultimate losers. Heart rate in winners remains elevated for at least 15 min after the contests have ended and animals have been returned to their home tanks. Reduced effects are seen in second and third pairings between familiar opponents. The sustained changes in heart rate that we observe in winning lobsters may result from hormonal modulation of cardiac function related to the change in social status brought about by contest outcome.

  16. Shelf life extension of whole Norway lobster Nephrops norvegicus using modified atmosphere packaging.

    Science.gov (United States)

    Gornik, Sebastian G; Albalat, Amaya; Theethakaew, Chonchanok; Neil, Douglas M

    2013-11-01

    Once a nuisance by-catch, today the Norway lobster (Nephrops norvegicus) is a valuable UK fisheries commodity. Unfortunately, the species is very susceptible to quality deterioration post harvest as it quickly develops black spots and also spoils rapidly due to bacterial growth. Treatment with chemicals can stop the blackening and carefully monitored cold storage can result in a sensory shelf life of up to 6.5 days. The high susceptibility to spoilage greatly restricts the extent to which N. norvegicus can be distributed to retailers and displayed for sale. The application of modified atmosphere (MA) could be extremely beneficial, allowing the chilled product to stay fresh for a long period of time, thus ensuring higher sales. In the present study, we identified a gas mix for the MA packaging (MAP) of whole N. norvegicus lobster into 200 g retail packs. Our results show that a shelf life extension to 13 days can be achieved when retail packs are stored in MAP at 1 °C. Effectiveness of the MAP was evaluated by using a newly developed QIM for MA-packaged whole N. norvegicus and also by analyzing bacterial plate counts. Changes in the microflora and effects of different storage temperatures on the quality of the MA packs are also presented. The main specific spoilage organism (SSO) of modified atmosphere packaged Norway lobster is Photobacterium phosphoreum. © 2013.

  17. Molecular, Biochemical, and Dietary Regulation Features of α-Amylase in a Carnivorous Crustacean, the Spiny Lobster Panulirus argus

    Science.gov (United States)

    Martos-Sitcha, Juan Antonio; Perdomo-Morales, Rolando; Casuso, Antonio; Montero-Alejo, Vivian; García-Galano, Tsai; Martínez-Rodríguez, Gonzalo; Mancera, Juan Miguel

    2016-01-01

    Alpha-amylases are ubiquitously distributed throughout microbials, plants and animals. It is widely accepted that omnivorous crustaceans have higher α-amylase activity and number of isoforms than carnivorous, but contradictory results have been obtained in some species, and carnivorous crustaceans have been less studied. In addition, the physiological meaning of α-amylase polymorphism in crustaceans is not well understood. In this work we studied α-amylase in a carnivorous lobster at the gene, transcript, and protein levels. It was showed that α-amylase isoenzyme composition (i.e., phenotype) in lobster determines carbohydrate digestion efficiency. Most frequent α-amylase phenotype has the lowest digestion efficiency, suggesting this is a favoured trait. We revealed that gene and intron loss have occurred in lobster α-amylase, thus lobsters express a single 1830 bp cDNA encoding a highly conserved protein with 513 amino acids. This protein gives rise to two isoenzymes in some individuals by glycosylation but not by limited proteolysis. Only the glycosylated isoenzyme could be purified by chromatography, with biochemical features similar to other animal amylases. High carbohydrate content in diet down-regulates α-amylase gene expression in lobster. However, high α-amylase activity occurs in lobster gastric juice irrespective of diet and was proposed to function as an early sensor of the carbohydrate content of diet to regulate further gene expression. We concluded that gene/isoenzyme simplicity, post-translational modifications and low Km, coupled with a tight regulation of gene expression, have arose during evolution of α-amylase in the carnivorous lobster to control excessive carbohydrate digestion in the presence of an active α-amylase. PMID:27391425

  18. Molecular, Biochemical, and Dietary Regulation Features of α-Amylase in a Carnivorous Crustacean, the Spiny Lobster Panulirus argus.

    Directory of Open Access Journals (Sweden)

    Leandro Rodríguez-Viera

    Full Text Available Alpha-amylases are ubiquitously distributed throughout microbials, plants and animals. It is widely accepted that omnivorous crustaceans have higher α-amylase activity and number of isoforms than carnivorous, but contradictory results have been obtained in some species, and carnivorous crustaceans have been less studied. In addition, the physiological meaning of α-amylase polymorphism in crustaceans is not well understood. In this work we studied α-amylase in a carnivorous lobster at the gene, transcript, and protein levels. It was showed that α-amylase isoenzyme composition (i.e., phenotype in lobster determines carbohydrate digestion efficiency. Most frequent α-amylase phenotype has the lowest digestion efficiency, suggesting this is a favoured trait. We revealed that gene and intron loss have occurred in lobster α-amylase, thus lobsters express a single 1830 bp cDNA encoding a highly conserved protein with 513 amino acids. This protein gives rise to two isoenzymes in some individuals by glycosylation but not by limited proteolysis. Only the glycosylated isoenzyme could be purified by chromatography, with biochemical features similar to other animal amylases. High carbohydrate content in diet down-regulates α-amylase gene expression in lobster. However, high α-amylase activity occurs in lobster gastric juice irrespective of diet and was proposed to function as an early sensor of the carbohydrate content of diet to regulate further gene expression. We concluded that gene/isoenzyme simplicity, post-translational modifications and low Km, coupled with a tight regulation of gene expression, have arose during evolution of α-amylase in the carnivorous lobster to control excessive carbohydrate digestion in the presence of an active α-amylase.

  19. Molecular, Biochemical, and Dietary Regulation Features of α-Amylase in a Carnivorous Crustacean, the Spiny Lobster Panulirus argus.

    Science.gov (United States)

    Rodríguez-Viera, Leandro; Perera, Erick; Martos-Sitcha, Juan Antonio; Perdomo-Morales, Rolando; Casuso, Antonio; Montero-Alejo, Vivian; García-Galano, Tsai; Martínez-Rodríguez, Gonzalo; Mancera, Juan Miguel

    2016-01-01

    Alpha-amylases are ubiquitously distributed throughout microbials, plants and animals. It is widely accepted that omnivorous crustaceans have higher α-amylase activity and number of isoforms than carnivorous, but contradictory results have been obtained in some species, and carnivorous crustaceans have been less studied. In addition, the physiological meaning of α-amylase polymorphism in crustaceans is not well understood. In this work we studied α-amylase in a carnivorous lobster at the gene, transcript, and protein levels. It was showed that α-amylase isoenzyme composition (i.e., phenotype) in lobster determines carbohydrate digestion efficiency. Most frequent α-amylase phenotype has the lowest digestion efficiency, suggesting this is a favoured trait. We revealed that gene and intron loss have occurred in lobster α-amylase, thus lobsters express a single 1830 bp cDNA encoding a highly conserved protein with 513 amino acids. This protein gives rise to two isoenzymes in some individuals by glycosylation but not by limited proteolysis. Only the glycosylated isoenzyme could be purified by chromatography, with biochemical features similar to other animal amylases. High carbohydrate content in diet down-regulates α-amylase gene expression in lobster. However, high α-amylase activity occurs in lobster gastric juice irrespective of diet and was proposed to function as an early sensor of the carbohydrate content of diet to regulate further gene expression. We concluded that gene/isoenzyme simplicity, post-translational modifications and low Km, coupled with a tight regulation of gene expression, have arose during evolution of α-amylase in the carnivorous lobster to control excessive carbohydrate digestion in the presence of an active α-amylase.

  20. Histología y ultraestructura del sistema reproductor masculino de la langosta espinosa de la India Panulirus homarus (Decapoda: Palinuridae

    Directory of Open Access Journals (Sweden)

    S Lakshmi Pillai

    2014-08-01

    Full Text Available La langosta espinosa Panulirus homarus, distribuida a lo largo de las costas sudeste y sudoeste de la India, es una especie de importancia comercial con gran potencial para la mari-cultura. A pesar de su importancia, las características estructurales y ultraestructurales de las gónadas masculinas de esta especie han sido poco estudiadas. Debido a esto, el objetivo de este estudio fue describir el aparato reproductor masculino de dicha especie, utilizando técnicas convencionales de microscopía histológica y electrónica. Se procesaron 94 ejemplares de P. homarus de vizhinjam (costa suroeste de la India (70 individuos para histología y 24 para ultraestructura, cuyos caparazones variaron de 37 mm a 92 mm de longitud. El sistema reproductor masculino de esta especie consistió en un par de testículos y un conducto deferente situados en la región céfalo-torácica. Macroscópicamente, el aparato reproductor se observó en langostas con una longitud de caparazón >35mm. En testículos inmaduros, la espermatogonia midió 6.9-13.8μm de diámetro y se encontró presente en los testículos maduros primarios (5.4-5.9μm, espermatocitos secundarios (2.8 a 3 μm y espermátidas (2.2-2.4μm. Cada conducto deferente consistió de porciones proximales y distales. La formación de la masa espermatofórica comienza en los conductos deferentes proximales. En el conducto deferente distal espermatofórico, la masa que contiene los espermatozoides está dispuesta en paquetes hacia la periferia, en una matriz gelatinosa producida por el tiflosol. Ultraestructuralmente, las espermatogonias presentan una lámina, núcleo y mitocondrias, los espermatocitos primarios tienen núcleo, cromatina densa y citoplasma vacuolado, mientras que las espermátidas tienen mitocondrias, retículo endoplasmático y centríolos. En las espermátidas, el retículo endoplásmico y la envoltura nuclear forman el acrosoma. Los brazos radiales con microtúbulos se forman en asociaci

  1. Chronic toxicity of contaminated sediments on reproduction and histopathology of the crustacean Gammarus fossarum and relationship with the chemical contamination and in vitro effects

    Energy Technology Data Exchange (ETDEWEB)

    Mazurova, Edita; Hilscherova, Klara; Sidlova-Stepankova, Tereza; Blaha, Ludek [Faculty of Science, RECETOX, Research Centre for Environmental Chemistry and Ecotoxicology, Masaryk Univ., Brno (Czech Republic); Koehler, Heinz R. [Animal Physiological Ecology, Univ. of Tuebingen (Germany); Triebskorn, Rita [Steinbeis-Transfer Center for Ecotoxicology and Ecophysiology, Rottenburg (Germany); Jungmann, Dirk [Inst. of Hydrobiology, Dresden Univ. of Tech. (Germany); Giesy, John P. [Dept. of Veterinary Biomedical Sciences and Toxicology Centre, Univ. of Saskatchewan, Saskatoon (Canada); Zoology Dept., National Food Safety and Toxicology Center, and Center for Integrative Toxicology Center, and Center for Integrative Toxicology, Michigan State Univ., East Lansing, MI (United States); Biology and Chemistry Dept., City Univ. of Hong Kong, Kowloon, Hong Kong (China); School of the Environment, Nanjing Univ. (China)

    2010-04-15

    The aim of the present study was to investigate possible relationships between the sediment contaminants and the occurrence of intersex in situ. Two of the studied sediments were from polluted sites with increased occurrence of intersex crustaceans (Lake Pilnok, black coal mining area in the Czech Republic, inhabited by the crayfish Pontastacus leptodactylus population with 18% of intersex; creek Lockwitzbach in Germany with Gammarus fossarum population with about 7% of intersex). Materials and methods Sediments were studied by a combined approach that included (1) determination of concentrations of metals and traditionally analyzed organic pollutants such as polychlorinated biphenyls, pesticides, and polycyclic aromatic hydrocarbons (PAHs); (2) examination of the in vitro potencies to activate aryl hydrocarbon (AhR), estrogen (ER), and androgen receptor-mediated responses; and (3) in vivo whole sediment exposures during a 12-week reproduction toxicity study with benthic amphipod G. fossarum. (orig.)

  2. Hygienic-sanitary working practices and implementation of a Hazard Analysis and Critical Control Point (HACCP plan in lobster processing industries

    Directory of Open Access Journals (Sweden)

    Cristina Farias da Fonseca

    2013-03-01

    Full Text Available This study aimed to verify the hygienic-sanitary working practices and to create and implement a Hazard Analysis Critical Control Point (HACCP in two lobster processing industries in Pernambuco State, Brazil. The industries studied process frozen whole lobsters, frozen whole cooked lobsters, and frozen lobster tails for exportation. The application of the hygienic-sanitary checklist in the industries analyzed achieved conformity rates over 96% to the aspects evaluated. The use of the Hazard Analysis Critical Control Point (HACCP plan resulted in the detection of two critical control points (CCPs including the receiving and classification steps in the processing of frozen lobster and frozen lobster tails, and an additional critical control point (CCP was detected during the cooking step of processing of the whole frozen cooked lobster. The proper implementation of the Hazard Analysis Critical Control Point (HACCP plan in the lobster processing industries studied proved to be the safest and most cost-effective method to monitor each critical control point (CCP hazards.

  3. Near-Infrared Spectroscopy as a Novel Non-Invasive Tool to Assess Spiny Lobster Nutritional Condition

    Science.gov (United States)

    Rodemann, Thomas; Carter, Chris G.

    2016-01-01

    Rapid non-invasive monitoring of spiny lobster nutritional condition has considerable application in the established fishery, live market and prospective aquaculture. The aim of this research was to test the feasibility of near-infrared spectroscopy (NIRS) as a novel non-invasive tool to assess the nutritional condition of three lobster species. Lobster (n = 92) abdominal muscle dry matter (AMDM) and carbon content (AMC) correlated significantly with indices of nutritional condition including hepatopancreas dry matter (HPDM; rho = 0.83, 0.78), total lipid content (HPTL; rho = 0.85, 0.87) and haemolymph total protein (TP; rho = 0.89, 0.87 respectively). Abdominal muscle nitrogen content (AMN) was a poor correlate of nutritional condition. Models based on FT-NIR scanning of whole lobster tails successfully predicted AMDM, AMN and AMC (RMSECV = 1.41%, 0.35% and 0.91%; R2 = 0.75, 0.65, 0.77, respectively), and to a lower accuracy HPDM, HPTL and TP (RMSECV = 6.22%, 8.37%, 18.4 g l-1; R2 = 0.51, 0.70, 0.83, respectively). NIRS was applied successfully to assess the condition of spiny lobsters non-invasively. This pilot study paves the way for the development of crustacean condition models using portable non-invasive devices in the laboratory or in the field. PMID:27442242

  4. A novel lobster-eye imaging system based on Schmidt-type objective for X-ray-backscattering inspection

    International Nuclear Information System (INIS)

    Xu, Jie; Wang, Xin; Zhan, Qi; Huang, Shengling; Chen, Yifan; Mu, Baozhong

    2016-01-01

    This paper presents a novel lobster-eye imaging system for X-ray-backscattering inspection. The system was designed by modifying the Schmidt geometry into a treble-lens structure in order to reduce the resolution difference between the vertical and horizontal directions, as indicated by ray-tracing simulations. The lobster-eye X-ray imaging system is capable of operating over a wide range of photon energies up to 100 keV. In addition, the optics of the lobster-eye X-ray imaging system was tested to verify that they meet the requirements. X-ray-backscattering imaging experiments were performed in which T-shaped polymethyl-methacrylate objects were imaged by the lobster-eye X-ray imaging system based on both the double-lens and treble-lens Schmidt objectives. The results show similar resolution of the treble-lens Schmidt objective in both the vertical and horizontal directions. Moreover, imaging experiments were performed using a second treble-lens Schmidt objective with higher resolution. The results show that for a field of view of over 200 mm and with a 500 mm object distance, this lobster-eye X-ray imaging system based on a treble-lens Schmidt objective offers a spatial resolution of approximately 3 mm.

  5. Effect of climate-related change in vegetation on leaf litter consumption and energy storage by Gammarus pulex from Continental or Mediterranean populations.

    Directory of Open Access Journals (Sweden)

    Natacha Foucreau

    Full Text Available As a consequence of global warming, it is important to characterise the potential changes occurring for some functional processes through the intra-specific study of key species. Changes in species distribution, particularly when key or engineer species are affected, should contribute to global changes in ecosystem functioning. In this study, we examined the potential consequences induced by global warming on ecosystem functioning in term of organic matter recycling. We compared consumption of leaf litter by some shredder populations (Gammarus pulex between five tree species inhabiting continental (i.e., the northern region of the Rhône River Valley and/or Mediterranean (i.e., the southern region of the Rhône River Valley conditions. To consider any potential adaptation of the gammarid population to vegetation in the same climate conditions, three populations of the key shredder Gammarus pulex from the northern region and three from the southern region of the Rhône River Valley were used. We experimentally compared the effects of the geographical origin of both the gammarid populations and the leaf litter species on the shredding activity and the physiological state of animals (through body triglyceride content. This study demonstrated that leaf toughness is more important than geographical origin for determining shredder leaf litter consumption. The overall consumption rate of the gammarid populations from the southern region of Rhône Valley was much higher than that of the populations from the northern region, but no clear differences between the origins of the leaf litter (i.e., continental vs. Mediterranean were observed. The northwards shift of G. pulex populations adapted to warmer conditions might significantly modify organic matter recycling in continental streams. As gammarid populations can demonstrate local adaptations to certain leaf species as a trophic resource, changes in riparian vegetation associated with climate change

  6. Single and combined effects of cadmium and arsenate in Gammarus pulex (Crustacea, Amphipoda): Understanding the links between physiological and behavioural responses

    Energy Technology Data Exchange (ETDEWEB)

    Vellinger, Céline, E-mail: celine.vellinger@gmail.com [Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, Université de Lorraine – Metz (France); Gismondi, Eric, E-mail: gismondi.eric@gmail.com [Laboratoire d’Ecologie animale et d’Ecotoxicologie, Institut de Chimie, Université de Liège, Allée du 6 Août 15, B-4000 Sart-Tilman, Liège (Belgium); Felten, Vincent, E-mail: vincent.felten@univ-lorraine.fr [Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, Université de Lorraine – Metz (France); Rousselle, Philippe, E-mail: rousselle@univ-lorraine.fr [Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, Université de Lorraine – Metz (France); Mehennaoui, Kahina, E-mail: meh_kahina@yahoo.fr [Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, Université de Lorraine – Metz (France); Parant, Marc, E-mail: parant@univ-lorraine.fr [Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, Université de Lorraine – Metz (France); Usseglio-Polatera, Philippe, E-mail: usseglio-polatera@univ-lorraine.fr [Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), CNRS UMR 7360, Université de Lorraine – Metz (France)

    2013-09-15

    Highlights: •Linking physiological to behavioural responses of G. pulex exposed to AsV and/or Cd. •AsV and/or Cd exposure exhibited similar biomarkers responses. •Contamination increases the mobilization of detoxification systems in gammarids. •Both changes in energy reserve use and allocation are involved in gammarid response. •Increased lipid peroxidation could be the cause of increasing gammarid mortality. -- Abstract: This study aimed at investigating the individual and interactive effects of cadmium (Cd) and arsenate (AsV) in Gammarus pulex (Crustacea, Amphipoda) through the use of several biomarkers. Individuals were exposed for 240 h to two concentrations of AsV or Cd alone, and all the possible binary mixtures of these concentrations of AsV and Cd in a complete factorial design. The pattern of the biomarkers’ responses to Cd and AsV alone or in mixture was similar in Gammarus pulex, even if the response intensity varied depending on the tested conditions. G. pulex responded to contamination with increased mobilization of the detoxification systems [i.e. γ-glutamyl-cystein ligase activity (GCL), reduced glutathione content (GSH) and metallothionein concentrations (MT)]. This response seems to imply changes in energy reserve utilization (total lipids and proteins are used prior to glycogen reserves), but also a possible energy reallocation from locomotion to detoxification processes. The observed increase in lipid peroxidation could be relied to the increasing gammarid mortality, despite the higher mobilization of detoxification systems. Even if the outcome of the complex interactions between AsV and Cd remains difficult to unravel, such studies are critically important for better assessing the effects of stressors on organisms, populations and communities in a multi-contamination context of ecosystems.

  7. Modelling Deep Water Habitats to Develop a Spatially Explicit, Fine Scale Understanding of the Distribution of the Western Rock Lobster, Panulirus cygnus

    Science.gov (United States)

    Hovey, Renae K.; Van Niel, Kimberly P.; Bellchambers, Lynda M.; Pember, Matthew B.

    2012-01-01

    Background The western rock lobster, Panulirus cygnus, is endemic to Western Australia and supports substantial commercial and recreational fisheries. Due to and its wide distribution and the commercial and recreational importance of the species a key component of managing western rock lobster is understanding the ecological processes and interactions that may influence lobster abundance and distribution. Using terrain analyses and distribution models of substrate and benthic biota, we assess the physical drivers that influence the distribution of lobsters at a key fishery site. Methods and Findings Using data collected from hydroacoustic and towed video surveys, 20 variables (including geophysical, substrate and biota variables) were developed to predict the distributions of substrate type (three classes of reef, rhodoliths and sand) and dominant biota (kelp, sessile invertebrates and macroalgae) within a 40 km2 area about 30 km off the west Australian coast. Lobster presence/absence data were collected within this area using georeferenced pots. These datasets were used to develop a classification tree model for predicting the distribution of the western rock lobster. Interestingly, kelp and reef were not selected as predictors. Instead, the model selected geophysical and geomorphic scalar variables, which emphasise a mix of terrain within limited distances. The model of lobster presence had an adjusted D2 of 64 and an 80% correct classification. Conclusions Species distribution models indicate that juxtaposition in fine scale terrain is most important to the western rock lobster. While key features like kelp and reef may be important to lobster distribution at a broad scale, it is the fine scale features in terrain that are likely to define its ecological niche. Determining the most appropriate landscape configuration and scale will be essential to refining niche habitats and will aid in selecting appropriate sites for protecting critical lobster habitats. PMID

  8. Modelling deep water habitats to develop a spatially explicit, fine scale understanding of the distribution of the western rock lobster, Panulirus cygnus.

    Directory of Open Access Journals (Sweden)

    Renae K Hovey

    Full Text Available BACKGROUND: The western rock lobster, Panulirus cygnus, is endemic to Western Australia and supports substantial commercial and recreational fisheries. Due to and its wide distribution and the commercial and recreational importance of the species a key component of managing western rock lobster is understanding the ecological processes and interactions that may influence lobster abundance and distribution. Using terrain analyses and distribution models of substrate and benthic biota, we assess the physical drivers that influence the distribution of lobsters at a key fishery site. METHODS AND FINDINGS: Using data collected from hydroacoustic and towed video surveys, 20 variables (including geophysical, substrate and biota variables were developed to predict the distributions of substrate type (three classes of reef, rhodoliths and sand and dominant biota (kelp, sessile invertebrates and macroalgae within a 40 km(2 area about 30 km off the west Australian coast. Lobster presence/absence data were collected within this area using georeferenced pots. These datasets were used to develop a classification tree model for predicting the distribution of the western rock lobster. Interestingly, kelp and reef were not selected as predictors. Instead, the model selected geophysical and geomorphic scalar variables, which emphasise a mix of terrain within limited distances. The model of lobster presence had an adjusted D(2 of 64 and an 80% correct classification. CONCLUSIONS: Species distribution models indicate that juxtaposition in fine scale terrain is most important to the western rock lobster. While key features like kelp and reef may be important to lobster distribution at a broad scale, it is the fine scale features in terrain that are likely to define its ecological niche. Determining the most appropriate landscape configuration and scale will be essential to refining niche habitats and will aid in selecting appropriate sites for protecting critical

  9. Modelling deep water habitats to develop a spatially explicit, fine scale understanding of the distribution of the western rock lobster, Panulirus cygnus.

    Science.gov (United States)

    Hovey, Renae K; Van Niel, Kimberly P; Bellchambers, Lynda M; Pember, Matthew B

    2012-01-01

    The western rock lobster, Panulirus cygnus, is endemic to Western Australia and supports substantial commercial and recreational fisheries. Due to and its wide distribution and the commercial and recreational importance of the species a key component of managing western rock lobster is understanding the ecological processes and interactions that may influence lobster abundance and distribution. Using terrain analyses and distribution models of substrate and benthic biota, we assess the physical drivers that influence the distribution of lobsters at a key fishery site. Using data collected from hydroacoustic and towed video surveys, 20 variables (including geophysical, substrate and biota variables) were developed to predict the distributions of substrate type (three classes of reef, rhodoliths and sand) and dominant biota (kelp, sessile invertebrates and macroalgae) within a 40 km(2) area about 30 km off the west Australian coast. Lobster presence/absence data were collected within this area using georeferenced pots. These datasets were used to develop a classification tree model for predicting the distribution of the western rock lobster. Interestingly, kelp and reef were not selected as predictors. Instead, the model selected geophysical and geomorphic scalar variables, which emphasise a mix of terrain within limited distances. The model of lobster presence had an adjusted D(2) of 64 and an 80% correct classification. Species distribution models indicate that juxtaposition in fine scale terrain is most important to the western rock lobster. While key features like kelp and reef may be important to lobster distribution at a broad scale, it is the fine scale features in terrain that are likely to define its ecological niche. Determining the most appropriate landscape configuration and scale will be essential to refining niche habitats and will aid in selecting appropriate sites for protecting critical lobster habitats.

  10. Predicting transport survival of brindle and red rock lobsters Jasus edwardsii using haemolymph biochemistry and behaviour traits.

    Science.gov (United States)

    Simon, Cedric J; Mendo, Tania C; Green, Bridget S; Gardner, Caleb

    2016-11-01

    Mortality events during live transport of Jasus edwardsii rock lobsters are common around the time of season openings in Tasmania, with lobsters from deeper fishing areas with pale shell colouration (brindle) being perceived as more susceptible than shallow-water, red-coloured (red) lobsters. The aims of this study were to assess and predict the vulnerability of brindle and red lobsters to extended emersion exposure using pre- and post-emersion data which included 28 haemolymph biochemical parameters and 5 behaviour traits. No effect of lobster shell colour on haemolymph biochemistry, behaviour traits and their vulnerability to emersion was found. A combined survival of 97% after 40h and 57% after 64h in a first experiment, and 37% after 64h in a second experiment, was observed. Behaviour traits (i.e., righting response, tail flips and three reflex behaviours) were poor indicator of survival. Haemolymph parameters were either unaffected by emersion (e.g., Brix index, protein and lipids), affected by emersion but not associated with mortality (e.g., total haemocyte counts, calcium, magnesium, bicarbonate, glucose and uric acid), or associated with mortality following a recovery period (e.g., pH, the sodium to potassium ratio, urea, and the activity of amylase). A build-up of anaerobic end-products and nitrogenous waste most likely resulted in the mortality. A model based on lobster size and the pre-emersion concentration of haemolymph bicarbonate and haemocyanin was found to be a useful indicator of future survival. This study provides promising leads towards the development of a blood based vulnerability test for live crustacean prior transport. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. ISS-Lobster: A Proposed Wide-Field X-Ray Telescope on the International Space Station

    Science.gov (United States)

    Camp, Jordan

    2012-01-01

    The Lobster wide-field imaging telescope combines simultaneous high FOV, high sensitivity and good position resolution. These characteristics can open the field of X-Ray time domain astronomy, which will study many interesting transient sources, including tidal disruptions of stars, supernova shock breakouts, and high redshift gamma-ray bursts. Also important will be its use for the X-ray follow-up of gravitational wave detections. I will describe our present effort to propose the Lobster concept for deployment on the International Space Station through a NASA Mission of Opportunity this fall.

  12. Mechanosensory Neurons With Bend- and Osmo-sensitivity in Mouthpart Setae From the Spiny Lobster Panulirus argus

    DEFF Research Database (Denmark)

    Garm, Anders; Derby, Charles D; Høeg, Jens T

    2004-01-01

    The mouthparts of the spiny lobster Panulirus argus hold primarily two types of setae--simple setae and cuspidate setae. Mechanosensory neurons from these setae were examined by electrophysiological recordings. The population of simple setae contained two types of mechanosensory neurons: displace......The mouthparts of the spiny lobster Panulirus argus hold primarily two types of setae--simple setae and cuspidate setae. Mechanosensory neurons from these setae were examined by electrophysiological recordings. The population of simple setae contained two types of mechanosensory neurons...

  13. Low-coverage MiSeq next generation sequencing reveals the mitochondrial genome of the Eastern Rock Lobster, Sagmariasus verreauxi.

    Science.gov (United States)

    Doyle, Stephen R; Griffith, Ian S; Murphy, Nick P; Strugnell, Jan M

    2015-01-01

    The complete mitochondrial genome of the Eastern Rock lobster, Sagmariasus verreauxi, is reported for the first time. Using low-coverage, long read MiSeq next generation sequencing, we constructed and determined the mtDNA genome organization of the 15,470 bp sequence from two isolates from Eastern Tasmania, Australia and Northern New Zealand, and identified 46 polymorphic nucleotides between the two sequences. This genome sequence and its genetic polymorphisms will likely be useful in understanding the distribution and population connectivity of the Eastern Rock Lobster, and in the fisheries management of this commercially important species.

  14. Lobster and Conch Fisheries of Belize: a History of Sequential Exploitation

    Directory of Open Access Journals (Sweden)

    Miriam Huitric

    2005-06-01

    Full Text Available This article presents a historical review of the lobster and conch fisheries in Belize, Central America. In terms of yield and value, these are the main wild-caught targets of the national fisheries, a small-scale commercial fishery of around 3000 fishermen. Data were collected during interviews with key informants involved with the fisheries and through literature and archive research. The goal was to study how the fishing industry has responded to environmental signals from these resources and from their ecosystems and ecosystem dynamics. National yields for both lobster and conch have been relatively stable, however, individuals' yields have been declining despite increased effort since the 1980s. This study concludes that the use of fossil fuel-based technology and organizational change, with the establishment of fishermen's cooperatives, have masked environmental signals. This masking, together with economic incentives, has led to the "pathology of resource use." As a symptom of this pathology, four forms of sequential exploitation in these fisheries were identified. A major conclusion is that social resilience may not confer ecological resilience. The development of the cooperatives was needed in order to improve equity in the industry. Before their impacts could be assessed, this organizational change, together with new technology, led to very important and rapid changes in the industry. Together with existing regulations that allow de facto open access to lobster and conch, these changes resulted in a short-term boom that has resulted in the pathology of resource use, with over-capitalization and dependence on maintained yields, regardless of environmental feedback.

  15. X-ray astronomy 2000: Wide field X-ray monitoring with lobster-eye telescopes

    International Nuclear Information System (INIS)

    Inneman, A.; Hudec, R.; Pina, L.; Gorenstein, P.

    2001-01-01

    The recently available first prototypes of innovative very wide field X-ray telescopes of Lobster-Eye type confirm the feasibility to develop such flight instruments in a near future. These devices are expected to allow very wide field (more than 1000 square degrees) monitoring of the sky in X-rays (up to 10 keV and perhaps even more) with faint limits. We will discuss the recent status of the development of very wide field X-ray telescopes as well as related scientific questions including expected major contributions such as monitoring and study of X-ray afterglows of Gamma Ray Bursts

  16. LOBSTER AIR TAWAR (Parastacidae: Cherax, ASPEK BIOLOGI, HABITAT, PENYEBARAN, DAN POTENSI PENGEMBANGANNYA

    Directory of Open Access Journals (Sweden)

    Titin Kurniasih

    2008-06-01

    Full Text Available Lobster air tawar (genus Cherax berasal dari Australia, Papua New Guinea, dan Irian Jaya, dengan spesies yang berbeda-beda. Salah satu spesiesnya yang bernilai ekonomis paling tinggi adalah Cherax quadricarinatus (red claw. Habitat Cherax adalah perairan tawar yang dangkal, dengan substrat berlumpur dan banyak terdapat celah serta rongga untuk menyembunyikan diri. Kelebihan terbaiknya adalah teknik budidayanya yang relatif mudah, toleransi terhadap lingkungan cukup tinggi dengan masalah penyakit yang relatif sedikit. Hanya disayangkan hingga saat ini perkembangan kegiatan budidaya Cherax masih sangat terbatas.

  17. Effects of drilling muds on lobster behavior. Progress report, 1 January-1 October 1979

    Energy Technology Data Exchange (ETDEWEB)

    Atema, J; Ashkenas, L; Beale, E

    1979-01-01

    Drilling muds, used and discarded in great quantities during the drilling phase of exploration and production of oil wells, represent an unknown threat to the marine environment. The compositions of the muds vary greatly with drilling requirements. The toxicity of their components are largely unknown, but can range from apparently harmless to immediately lethal, as found recently in toxicity tests on a number of marine animals. This report contains eight sections, each describing an aspect of studies of lobster behavior, ecology, physiology and the effects of exposure to various levels of different drilling muds.

  18. Variability in prevalence of Cymatocarpus solearis (Trematoda, Brachycoeliidae) in Caribbean spiny lobsters Panulirus argus (Decapoda: Palinuridae) from Bahía de la Ascensión (Mexico).

    Science.gov (United States)

    Briones-Fourzán, Patricia; Muñoz de Cote-Hernández, Rubén; Lozano-Álvarez, Enrique

    2016-06-01

    Cymatocarpus solearis, a brachycoeliid trematode that parasitizes sea turtles, uses spiny lobsters Panulirus argus as second intermediate hosts. We examined variability in infection by C. solearis in Bahía de la Ascensión, Mexico, a tropical bay with a highly productive fishery for P. argus that is based on the extensive use of casitas (large artificial shelters), which can harbor multiple juveniles and adults of this gregarious lobster species. We sampled 3956 lobsters from 466 casitas distributed over three bay zones within two closed seasons and one fishing season. In these lobsters (9.5-115.2mm carapace length, CL), the average infection prevalence was 11.7% but the probability of infection increased significantly with size. Prevalence varied with season but was consistently higher in one zone than in the other two zones. Infection with C. solearis was negatively related with clinical infection with Panulirus argus Virus 1 (PaV1). We also sampled 405 lobsters from the commercial catch obtained throughout the bay at the onset of the fishing season. In these relatively larger lobsters (70.3-168.0mm CL), average prevalence of C. solearis was higher (23.5%) but was not affected by lobster size or sex. Encysted metacercariae occurred in both abdominal and cephalothoracic muscles. The effects of C. solearis on phenotypic traits of P. argus that may potentially impact the host population dynamics and fisheries remain to be investigated. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Physiological and immunological characterization of Caribbean spiny lobsters Panulirus argus naturally infected with Panulirus argus Virus 1 (PaV1).

    Science.gov (United States)

    Pascual Jiménez, Cristina; Huchin-Mian, Juan Pablo; Simões, Nuno; Briones-Fourzán, Patricia; Lozano-Álvarez, Enrique; Sánchez Arteaga, Ariadna; Pérez-Vega, Juan Antonio; Simá-Álvarez, Raúl; Rosas Vazquez, Carlos; Rodríguez-Canul, Rossanna

    2012-08-27

    The present study compares 13 physiological and immunological variables between a group of healthy Panulirus argus lobsters and a group of lobsters naturally infected with Panulirus argus Virus 1 (PaV1). Viral infection was determined through histopathology and PCR. Ten of the 13 variables differed significantly between the 2 groups. Using these variables, a principal component analysis yielded 2 separate clusters: one corresponding to the healthy group and the other corresponding to the infected group. In particular, infected lobsters exhibited significantly lower levels of osmotic pressure, total hemocyte counts, plasmatic proteins, and total phenoloxidase (PO) activity in plasma, as well as significantly higher levels of cholesterol and acylglycerides. These features are consistent with metabolic wasting, hyperlipidemia, and presumed immune suppression. Infection with PaV1 appears to increase the susceptibility of lobsters to some other opportunistic pathogens, as 61.1% of infected lobsters presented infestations of ciliate epibionts (Epystilis and Zoothamniun) in the gill chamber compared with 11.5% lobsters in the healthy group. Infected lobsters also showed significantly higher levels of total PO activity in degranulated hemocytes and trypsin inhibitor activity, potentially indicating activation of immune response by the PO system during the systemic infection with PaV1.

  20. Variability in clinical prevalence of PaV1 in Caribbean spiny lobsters occupying commercial casitas over a large bay in Mexico.

    Science.gov (United States)

    Candia-Zulbarán, Rebeca I; Briones-Fourzán, Patricia; Negrete-Soto, Fernando; Barradas-Ortiz, Cecilia; Lozano-Álvarez, Enrique

    2012-08-27

    In Bahía de la Ascensión, Mexico, the fishery for spiny lobsters Panulirus argus is based on the extensive use of casitas, large artificial shelters that can harbor the full size range of these highly gregarious lobsters. The discovery of a pathogenic virus in these lobsters (Panulirus argus virus 1, or PaV1) has raised concern about its potential effects on casita-based fisheries. Because in Bahía de la Ascensión visibly infected lobsters represent an immediate loss of revenue, we examined variability in clinical prevalence of PaV1 (percentage of lobsters visibly infected) in thousands of lobsters sampled from the commercial catch at the onset of 3 consecutive fishing years, and from 530 casitas distributed over 3 zones within the bay during 2 fishing and 2 closed seasons. In the commercial catch (lobsters 67 to 147 mm carapace length [CL]), clinical prevalence of PaV1 was low and was not affected by year or sex. In lobsters (9.2 to 115.0 mm CL) that occupied casitas, clinical prevalence of PaV1 varied with sampling season and was always higher in juveniles than in subadults or adults, but was consistently lower in one zone relative to the other 2 zones. The average clinical prevalence of PaV1 in this bay was statistically similar to the average clinical prevalence reported in Cuba, where casitas are also used, and in Florida Bay, USA, where casitas are not used. To date, PaV1 has had no discernible impact on the lobster fishery in Bahía de la Ascensión, suggesting that clinical prevalence is not influenced by the use of casitas per se.

  1. Prevalence of Panulirus argus Virus 1 (PaV1) and habitation patterns of healthy and diseased Caribbean spiny lobsters in shelter-limited habitats.

    Science.gov (United States)

    Lozano-Alvarez, Enrique; Briones-Fourzán, Patricia; Ramírez-Estévez, Aurora; Placencia-Sánchez, David; Huchin-Mian, Juan Pablo; Rodríguez-Canul, Rossana

    2008-07-07

    Caribbean spiny lobsters Panulirus argus are socially gregarious, preferring shelters harboring conspecifics over empty shelters. In laboratory trials, however, healthy lobsters strongly avoided shelters harboring lobsters infected with the highly pathogenic Panulirus argus Virus 1 (PaV1). Because PaV1 is transmitted by contact, this behavior may thwart its spread in wild lobsters. In a field experiment conducted from 1998 to 2002 in a shelter-poor reef lagoon (Puerto Morelos, Mexico), densities of juvenile P. argus increased significantly on sites enhanced with artificial shelters (casitas) but not on control sites. Because PaV1 emerged in this location during 2000, we reexamined these data to assess whether casitas could potentially increase transmission of PaV1. In 2001, PaV1 prevalence was 2.5% and the cohabitation level (percentage of healthy lobsters cohabiting with diseased lobsters) was similar between natural shelters (3.5%) and casitas (2.4 %). The relative lobster densities in casita sites and control sites did not change significantly before (1998-1999) or after (2001-2002) the disease emergence. In late 2006, data from casita sites showed a significant increase in prevalence (10.9%) and cohabitation level (29.4%), but no significant changes in lobster density. In May 2006, casitas were deployed on shelter-poor sites within Chinchorro Bank, 260 km south of Puerto Morelos. In late 2006, prevalence and cohabitation level were 7.4 and 21.7%, respectively. Our results are inconclusive as to whether or not casitas increase PaV1 transmission, but suggest that across shelter-poor habitats, lobsters make a trade-off between avoiding diseased conspecifics and avoiding predation risk.

  2. "Intermetamorphic" developmental stages in 150 million-year-old achelatan lobsters--The case of the species tenera Oppel, 1862.

    Science.gov (United States)

    Haug, Joachim T; Haug, Carolin

    2016-03-01

    We re-investigated the fossil species tenera Oppel, 1862, an achelatan lobster (traditionally named Palinurina tenera) found in 150 million years old limestones of southern Germany. All known specimens attributed to this species show a mixture of characters, which in modern forms occur either in larvae or post-larval juveniles. Hence these specimens provide insight into a phase in ontogeny that is no longer present in the developmental sequence of any modern achelatan lobster, as the latter ones skip this phase and replace it by a drastic metamorphosis. Comparable cases have been described earlier, yet did only comprise single stages or two successive ones at most. In the here described case four developmental stages are preserved. The reconstructed ontogeny of tenera therefore represents the currently best known sequence of an early achelatan lobster that covers this specific intermediate phase. The largest known stage most likely still represents an immature of a yet undiscovered adult. These findings support the interpretation that early achelatan lobsters developed in a more gradual ontogenetic sequence than modern forms. It furthermore demonstrates that it was even more gradual than anticipated previously. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Ultrastructure and functional organization of mouthpart sensory setae of the spiny lobster Panulirus argus: new features of putative mechanoreceptors

    DEFF Research Database (Denmark)

    Garm, Anders Lydik; Høeg, Jens T

    2006-01-01

    In comparison with other decapods, the Caribbean spiny lobster Panulirus argus has little diversity in the external morphology of the setae on the mouth apparatus. In mouthpart areas that frequently touch food items only two types of setae can be distinguished: simple setae and cuspidate setae...

  4. Comparative electron microscopy and image analysis of oxy- and deoxy-hemocyanin from the spiny lobster Panulirus interruptus

    NARCIS (Netherlands)

    Haas, Felix de; Breemen, Jan F.L. van; Boekema, Egbert J.; Keegstra, Wilko; Bruggen, Ernst F.J. van

    1993-01-01

    Structural differences between oxy-hemocyanin and deoxy-hemocyanin from the spiny lobster P. interruptus were studied by electron microscopy and image analysis of negatively stained preparations. Projections of the hexameric P. interruptus hemocyanin from electron microscopy were compared with

  5. Scyllarides obtusus spec. nov., the scyllarid lobster of Saint Helena, Central South Atlantic (Crustacea: Decapoda Reptantia: Scyllaridae)

    NARCIS (Netherlands)

    Holthuis, L.B.

    1993-01-01

    A new species of slipper lobster is described from Saint Helena, where the species seems to be endemic. Known under the vernacular name Stump, the species forms the subject of a local fishery, carried out since early times. Previously the species has been identified with various Scyllarides species

  6. Influence of twin and multi-rig trawl systems on CPUE in the Danish Norway lobster (Nephrops norvegicus) fishery

    DEFF Research Database (Denmark)

    Feekings, Jordan P.; Berg, Casper Willestofte; Krag, Ludvig Ahm

    2016-01-01

    analyse catchrates of four target species, Norway lobster (Nephrops norvegicus), cod (Gadus morhua), plaice (Pleuronectesplatessa) and haddock (Melanogrammus aeglefinus), to try and understand how the use of multi-rig trawlshave altered catch rates within the Danish demersal trawl fishery over the last 16...

  7. Phylogenetic relationships, character evolution, and taxonomic implications within the slipper lobsters (Crustacea: Decapoda: Scyllaridae).

    Science.gov (United States)

    Yang, Chien-Hui; Bracken-Grissom, Heather; Kim, Dohyup; Crandall, Keith A; Chan, Tin-Yam

    2012-01-01

    The slipper lobsters belong to the family Scyllaridae which contains a total of 20 genera and 89 species distributed across four subfamilies (Arctidinae, Ibacinae, Scyllarinae, and Theninae). We have collected nucleotide sequence data from regions of five different genes (16S, 18S, COI, 28S, H3) to estimate phylogenetic relationships among 54 species from the Scyllaridae with a focus on the species rich subfamily Scyllarinae. We have included in our analyses at least one representative from all 20 genera in the Scyllaridae and 35 of the 52 species within the Scyllarinae. Our resulting phylogenetic estimate shows the subfamilies are monophyletic, except for Ibacinae, which has paraphyletic relationships among genera. Many of the genera within the Scyllarinae form non-monophyletic groups, while the genera from all other subfamilies form well supported clades. We discuss the implications of this history on the evolution of morphological characters and ecological transitions (nearshore vs. offshore) within the slipper lobsters. Finally, we identify, through ancestral state character reconstructions, key morphological features diagnostic of the major clades of diversity within the Scyllaridae and relate this character evolution to current taxonomy and classification. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Redefining metamorphosis in spiny lobsters: molecular analysis of the phyllosoma to puerulus transition in Sagmariasus verreauxi.

    Science.gov (United States)

    Ventura, Tomer; Fitzgibbon, Quinn P; Battaglene, Stephen C; Elizur, Abigail

    2015-08-27

    The molecular understanding of crustacean metamorphosis is hindered by small sized individuals and inability to accurately define molt stages. We used the spiny lobster Sagmariasus verreauxi where the large, transparent larvae enable accurate tracing of the transition from a leaf-shaped phyllosoma to an intermediate larval-juvenile phase (puerulus). Transcriptomic analysis of larvae at well-defined stages prior to, during, and following this transition show that the phyllosoma-puerulus metamorphic transition is accompanied by vast transcriptomic changes exceeding 25% of the transcriptome. Notably, genes previously identified as regulating metamorphosis in other crustaceans do not fluctuate during this transition but in the later, morphologically-subtle puerulus-juvenile transition, indicating that the dramatic phyllosoma-puerulus morphological shift relies on a different, yet to be identified metamorphic mechanism. We examined the change in expression of domains and gene families, with focus on several key genes. Our research implies that the separation in molecular triggering systems between the phyllosoma-puerulus and puerulus-juvenile transitions might have enabled the extension of the oceanic phase in spiny lobsters. Study of similar transitions, where metamorphosis is uncoupled from the transition into the benthic juvenile form, in other commercially important crustacean groups might show common features to point on the evolutionary advantage of this two staged regulation.

  9. Grow-out of spiny lobster Panulirus sp. with high stocking density in controlled tanks

    Directory of Open Access Journals (Sweden)

    Rio Yusufi Subhan

    2018-05-01

    Full Text Available ABSTRACTThe aim of this research was to determine optimum stocking density for growing-out of spiny lobster Panulirus sp. in controlled tanks that conducted for 30 days. The experimental spiny lobsters have the initial average weight of 130.39 ± 0.32 g and initial average total length of 140.70 ± 0.06 mm. This study used completely randomized design with three different stocking densities (KT10: 10 ind/m3; KT18: 18 ind/m3; and KT26: 26 ind/m3 and two replications. The parameters observed in this study included water quality (temperature, pH, salinity, dissolved oxygen, and total ammonia nitrogen, physiological responses (total haemocyte count, haemolymph glucose, and frequency of molt, and production performances, such as growth, specific growth rate, feed conversion ratio, and survival rate. The results showed that the spiny lobster could be reared in high stocking density in controlled tanks. Water quality during the study in each treatment was; temperature 26.56–28.65oC, salinity 29.7–33.6 g/L, pH 7.5–8.5, dissolved oxygen 6.15–6.58 mg/L, and total ammonia nitrogen 0.11–0.34 mg/L. The best stocking densities for spiny lobster was 18 ind/m3 (KT18 with 2.5‒3.5×106cells/mL total haemocyte counts, 24.6‒28.3 mg/dL haemolymph glucose, and 38.37 ± 3.20% frequency of molt. The final average body weight and length were 145.06 ± 0.42 g and 142.77 ± 0.19 mm, respectively. The survival rate reached 86.11 ± 3.92% with a specific growth rate 0.35 ± 0.01%/day, and feed conversion ratio 7.87 ± 0.31.Keywords: high stocking density, Panulirus sp., physiological responses, productivity.  ABSTRAKTujuan dari penelitian ini adalah untuk menentukan kepadatan terbaik dalam pembesaran lobster laut Panulirus sp. yang dipelihara dalam bak terkontrol selama 30 hari. Lobster laut yang digunakan pada awal penelitian memiliki bobot 130,39 ± 0,32 g dan panjang total 140,70 ± 0,06 mm. Penelitian dilakukan menggunakan rancangan acak lengkap dengan

  10. Spiny lobsters detect conspecific blood-borne alarm cues exclusively through olfactory sensilla.

    Science.gov (United States)

    Shabani, Shkelzen; Kamio, Michiya; Derby, Charles D

    2008-08-01

    When attacked by predators, diverse animals actively or passively release molecules that evoke alarm and related anti-predatory behavior by nearby conspecifics. The actively released molecules are alarm pheromones, whereas the passively released molecules are alarm cues. For example, many insects have alarm-signaling systems that involve active release of alarm pheromones from specialized glands and detection of these signals using specific sensors. Many crustaceans passively release alarm cues, but the nature of the cues, sensors and responses is poorly characterized. Here we show in laboratory and field experiments that injured Caribbean spiny lobsters, Panulirus argus, passively release alarm cues via blood (hemolymph) that induce alarm responses in the form of avoidance and suppression of feeding. These cues are detected exclusively through specific olfactory chemosensors, the aesthetasc sensilla. The alarm cues for Caribbean spiny lobsters are not unique to the species but do show some phylogenetic specificity: P. argus responds primarily with alarm behavior to conspecific blood, but with mixed alarm and appetitive behaviors to blood from the congener Panulirus interruptus, or with appetitive behaviors to blood from the blue crab Callinectes sapidus. This study lays the foundation for future neuroethological studies of alarm cue systems in this and other decapod crustaceans.

  11. Agonistic behaviour in juvenile southern rock lobster, Jasus edwardsii (Decapoda, Palinuridae: implications for developing aquaculture

    Directory of Open Access Journals (Sweden)

    Chris Carter

    2014-11-01

    Full Text Available The Southern rock lobster, Jasus edwardsii, is a temperate species of spiny lobster with established well managed fisheries in Australia and New Zealand. It has also been under consideration as a species with aquaculture potential. Agonistic behaviour has important consequences under aquaculture conditions that encompass direct effects, such as damage or death of protagonists, and indirect effects on growth that relate to resource access, principally food and refuge. This study aimed to identify and characterize behaviours and to make a preliminary investigation of their occurrence under tank culture. Juvenile Jasus edwardsii were examined in a flow-through seawater system using a remote video camera system. Twenty-nine behaviours were divided into three sub-groups: aggressive (11, avoidance (6 and others (12. Aggressive behaviours included attacks, pushing, lifting, clasping and carrying an opponent. Avoidance behaviours included moving away in a backwards-, forwards- or side-stepping motion as well as with more vigorous tail flips. These behaviours were components of twelve behavioural groups that described contact, attack and displacement between individuals. Activity was crepuscular with two clear peaks, one in the morning and the other in the evening. The occurrence of behavioural groups was not different between the morning and evening. The frequency of aggressive behaviours was not affected by changes made to stocking density or access to food. The implications of agonistic behaviours are discussed further in relation to developing aquaculture.

  12. Redefining metamorphosis in spiny lobsters: molecular analysis of the phyllosoma to puerulus transition in Sagmariasus verreauxi

    Science.gov (United States)

    Ventura, Tomer; Fitzgibbon, Quinn P.; Battaglene, Stephen C.; Elizur, Abigail

    2015-01-01

    The molecular understanding of crustacean metamorphosis is hindered by small sized individuals and inability to accurately define molt stages. We used the spiny lobster Sagmariasus verreauxi where the large, transparent larvae enable accurate tracing of the transition from a leaf-shaped phyllosoma to an intermediate larval-juvenile phase (puerulus). Transcriptomic analysis of larvae at well-defined stages prior to, during, and following this transition show that the phyllosoma-puerulus metamorphic transition is accompanied by vast transcriptomic changes exceeding 25% of the transcriptome. Notably, genes previously identified as regulating metamorphosis in other crustaceans do not fluctuate during this transition but in the later, morphologically-subtle puerulus-juvenile transition, indicating that the dramatic phyllosoma-puerulus morphological shift relies on a different, yet to be identified metamorphic mechanism. We examined the change in expression of domains and gene families, with focus on several key genes. Our research implies that the separation in molecular triggering systems between the phyllosoma-puerulus and puerulus-juvenile transitions might have enabled the extension of the oceanic phase in spiny lobsters. Study of similar transitions, where metamorphosis is uncoupled from the transition into the benthic juvenile form, in other commercially important crustacean groups might show common features to point on the evolutionary advantage of this two staged regulation. PMID:26311524

  13. Evolutionary morphology of the organ systems in squat lobsters and porcelain crabs (crustacea: Decapoda: Anomala): an insight into carcinization.

    Science.gov (United States)

    Keiler, Jonas; Richter, Stefan; Wirkner, Christian S

    2015-01-01

    Porcelain crabs (Porcellanidae) are one of three taxa within anomuran crustaceans (Anomala) which possess a crab-like body form. Curiously, these three lineages evolved this shape independently from true crabs (Brachyura) in the course of the evolutionary process termed carcinization. The entire pleon in porcelain crabs is flexed under the cephalothorax and the carapace is approximately as broad as long. Despite their crab-like habitus, porcelain crabs are phylogenetically nested within squat lobsters (Munidopsidae, Munididae, Galatheidae). With a pleon which is only partly flexed under the cephalothorax and a cephalothorax which is longer than it is broad, squat lobsters represent morphologically intermediate forms between lobster-like and crab-like body shapes. Carcinization has so far mostly been studied with respect to outer morphology; however, it is evident that internal anatomical features are influenced through this change of body shape too. In this paper, the situation in Galatheoidea is elucidated by adding more taxa to existing descriptions of the hemolymph vascular systems and associated structures and organs. Micro-computer tomography and 3D reconstruction provide new insights. Autapomorphic states of various internal anatomical characters are present in nearly all the studied species, also reflecting some degree of anatomical disparity found within Galatheoidea. The ventral vessel system of porcelain crabs differs distinctly from that of squat lobsters. The differences in question are coherent (i.e. structural dependent) with morphological transformations in the integument, such as the shortening of the sternal plastron, which evolved in the course of carcinization. Shifts in the gonads and the pleonal neuromeres are coherent with the loss of the caridoid escape reaction, which in turn is a consequence of carcinization. The arterial transformations, however, are minor compared to other instances of carcinization in anomuran crustaceans since the last

  14. Applying Fishers' ecological knowledge to construct past and future lobster stocks in the Juan Fernandez Archipelago, Chile.

    Directory of Open Access Journals (Sweden)

    Tyler D Eddy

    Full Text Available Over-exploited fisheries are a common feature of the modern world and a range of solutions including area closures (marine reserves; MRs, effort reduction, gear changes, ecosystem-based management, incentives and co-management have been suggested as techniques to rebuild over-fished populations. Historic accounts of lobster (Jasus frontalis on the Chilean Juan Fernández Archipelago indicate a high abundance at all depths (intertidal to approximately 165 m, but presently lobsters are found almost exclusively in deeper regions of their natural distribution. Fishers' ecological knowledge (FEK tells a story of serial depletion in lobster abundance at fishing grounds located closest to the fishing port with an associated decline in catch per unit effort (CPUE throughout recent history. We have re-constructed baselines of lobster biomass throughout human history on the archipelago using historic data, the fishery catch record and FEK to permit examination of the potential effects of MRs, effort reduction and co-management (stewardship of catch to restore stocks. We employed a bioeconomic model using FEK, fishery catch and effort data, underwater survey information, predicted population growth and response to MR protection (no-take to explore different management strategies and their trade-offs to restore stocks and improve catches. Our findings indicate that increased stewardship of catch coupled with 30% area closure (MR provides the best option to reconstruct historic baselines. Based on model predictions, continued exploitation under the current management scheme is highly influenced by annual fluctuations and unsustainable. We propose a community-based co-management program to implement a MR in order to rebuild the lobster population while also providing conservation protection for marine species endemic to the Archipelago.

  15. Determining the diet of larvae of western rock lobster (Panulirus cygnus using high-throughput DNA sequencing techniques.

    Directory of Open Access Journals (Sweden)

    Richard O'Rorke

    Full Text Available The Western Australian rock lobster fishery has been both a highly productive and sustainable fishery. However, a recent dramatic and unexplained decline in post-larval recruitment threatens this sustainability. Our lack of knowledge of key processes in lobster larval ecology, such as their position in the food web, limits our ability to determine what underpins this decline. The present study uses a high-throughput amplicon sequencing approach on DNA obtained from the hepatopancreas of larvae to discover significant prey items. Two short regions of the 18S rRNA gene were amplified under the presence of lobster specific PNA to prevent lobster amplification and to improve prey amplification. In the resulting sequences either little prey was recovered, indicating that the larval gut was empty, or there was a high number of reads originating from multiple zooplankton taxa. The most abundant reads included colonial Radiolaria, Thaliacea, Actinopterygii, Hydrozoa and Sagittoidea, which supports the hypothesis that the larvae feed on multiple groups of mostly transparent gelatinous zooplankton. This hypothesis has prevailed as it has been tentatively inferred from the physiology of larvae, captive feeding trials and co-occurrence in situ. However, these prey have not been observed in the larval gut as traditional microscopic techniques cannot discern between transparent and gelatinous prey items in the gut. High-throughput amplicon sequencing of gut DNA has enabled us to classify these otherwise undetectable prey. The dominance of the colonial radiolarians among the gut contents is intriguing in that this group has been historically difficult to quantify in the water column, which may explain why they have not been connected to larval diet previously. Our results indicate that a PCR based technique is a very successful approach to identify the most abundant taxa in the natural diet of lobster larvae.

  16. Cadmium bound to metal rich granules and exoskeleton from Gammarus pulex causes increased gut lipid peroxidation in zebrafish following single dietary exposure

    International Nuclear Information System (INIS)

    Khan, F.R.; Bury, N.R.; Hogstrand, C.

    2010-01-01

    There has been a growing interest in establishing how the sub-cellular distribution of metals in macro-invertebrate prey affects metal trophic bioavailability and toxicity. In this study, the crustacean Gammarus pulex was exposed to 300 μg Cd l -1 spiked with 109 Cd for 13 days, from which the two principal metal containing sub-cellular fractions, the metallothionein-like protein (MTLP) and the metal rich granule and exoskeleton (MRG + exo) were isolated. These fractions were produced at equal metal content, incorporated into gelatin and fed to zebrafish as a single meal; assimilation efficiency (AE), carcass and gut tissue metal concentrations and gut lipid peroxidative damage measured as malondialdehyde (MDA) were assessed. The AE of cadmium bound to the MTLP fraction was 32.1 ± 5.6% which was significantly greater than the AE of MRG + exo bound Cd, 13.0 ± 2.1% (p -1 in fish fed MTLP-Cd compared to 9.5 ± 1.4 ng Cd g -1 in fish fed MRG + exo fraction. Both feeds led to significantly increased MDA levels compared to the control group (gelatin only feed), but MRG + exo feed caused significantly more oxidative damage than the MTLP feed (p < 0.01). Thus, MTLP-Cd is more bioavailable than the cadmium bound to granules and exoskeleton, but it was the latter fraction, largely considered as having limited bioavailability, that appeared to exert a greater localised oxidative injury to the digestive tract of zebrafish.

  17. Additive vs non-additive genetic components in lethal cadmium tolerance of Gammarus (Crustacea): Novel light on the assessment of the potential for adaptation to contamination

    International Nuclear Information System (INIS)

    Chaumot, Arnaud; Gos, Pierre; Garric, Jeanne; Geffard, Olivier

    2009-01-01

    Questioning the likelihood that populations adapt to contamination is critical for ecotoxicological risk assessment. The appraisal of genetic variance in chemical sensitivities within populations is currently used to evaluate a priori this evolutionary potential. Nevertheless, conclusions from this approach are questionable since non-additive genetic components in chemical tolerance could limit the response of such complex phenotypic traits to selection. Coupling quantitative genetics with ecotoxicology, this study illustrates how the comparison between cadmium sensitivities among Gammarus siblings enabled discrimination between genetic variance components in chemical tolerance. The results revealed that, whereas genetically determined differences in lethal tolerance exist within the studied population, such differences were not significantly heritable since genetic variance mainly relied on non-additive components. Therefore the potential for genetic adaptation to acute Cd stress appeared to be weak. These outcomes are discussed in regard to previous findings for asexual daphnids, which suggest a strong potency of genetic adaptation to environmental contamination, but which contrast with compiled field observations where adaptation is not the rule. Hereafter, we formulate the reconciling hypothesis of a widespread weakness of additive components in tolerance to contaminants, which needs to be further tested to gain insight into the question of the likelihood of adaptation to contamination.

  18. Biodegradable and Petroleum-Based Microplastics Do Not Differ in Their Ingestion and Excretion but in Their Biological Effects in a Freshwater Invertebrate Gammarus fossarum

    Directory of Open Access Journals (Sweden)

    Sandrine Straub

    2017-07-01

    Full Text Available Research on the uptake and effects of bioplastics by aquatic organisms is still in its infancy. Here, we aim to advance the field by comparing uptake and effects of microplastic particles (MPP of a biodegradable bioMPP (polyhydroxybutyrate (PHB and petroleum-based MPP (polymethylmethacrylate (PMMA in the freshwater amphipod Gammarus fossarum. Ingestion of both MPP in different particle sizes (32–250 µm occurred after 24 h, with highest ingestion of particles in the range 32–63 µm and almost complete egestion after 64 h. A four-week effect-experiment showed a significant decrease of the assimilation efficiency in amphipods exposed to the petroleum-based MPP from week two onwards. The petroleum-based PMMA affected assimilation efficiency significantly in contrast to the biodegradable PHB, but overall differences in direct comparison of MPP types were small. Both MPP types led to a significantly lower wet weight gain relative to the control treatments. After four weeks, differences between both MPP types and silica, used as a natural particle control, were detected. In summary, these results suggest that both MPP types provoke digestive constraints on the amphipods, which go beyond those of natural non-palatable particles. This highlights the need for more detailed research comparing environmental effects of biodegradable and petroleum-based MPP and testing those against naturally occurring particle loads.

  19. Biodegradable and Petroleum-Based Microplastics Do Not Differ in Their Ingestion and Excretion but in Their Biological Effects in a Freshwater Invertebrate Gammarus fossarum

    Science.gov (United States)

    Straub, Sandrine; Hirsch, Philipp E.; Burkhardt-Holm, Patricia

    2017-01-01

    Research on the uptake and effects of bioplastics by aquatic organisms is still in its infancy. Here, we aim to advance the field by comparing uptake and effects of microplastic particles (MPP) of a biodegradable bioMPP (polyhydroxybutyrate (PHB)) and petroleum-based MPP (polymethylmethacrylate (PMMA)) in the freshwater amphipod Gammarus fossarum. Ingestion of both MPP in different particle sizes (32–250 µm) occurred after 24 h, with highest ingestion of particles in the range 32–63 µm and almost complete egestion after 64 h. A four-week effect-experiment showed a significant decrease of the assimilation efficiency in amphipods exposed to the petroleum-based MPP from week two onwards. The petroleum-based PMMA affected assimilation efficiency significantly in contrast to the biodegradable PHB, but overall differences in direct comparison of MPP types were small. Both MPP types led to a significantly lower wet weight gain relative to the control treatments. After four weeks, differences between both MPP types and silica, used as a natural particle control, were detected. In summary, these results suggest that both MPP types provoke digestive constraints on the amphipods, which go beyond those of natural non-palatable particles. This highlights the need for more detailed research comparing environmental effects of biodegradable and petroleum-based MPP and testing those against naturally occurring particle loads. PMID:28703776

  20. From fishing to fish processing: Separation of fish from crustaceans in the Norway lobster-directed multispecies trawl fishery improves seafood quality

    DEFF Research Database (Denmark)

    Karlsen, Junita Diana; Krag, Ludvig Ahm; Albertsen, Christoffer Moesgaard

    2015-01-01

    Fishing gears have negative impacts on seafood quality, especially on fish in the mixed trawl fishery targeting Norway lobster (Nephrops norvegicus). In this fishery, which is worth about €80 millions in Denmark alone, the quality of fish can be significantly improved by simple gear changes....... A trawl codend divided into an upper and lower codend was designed to separate fish from Norway lobster during the fishing process by encourage fish to swim into the upper codend by using a frame at the entrance of the lower codend. Separate codends for fish and Norway lobster in the same gear provide...... with hard or spiny surfaces due to successful separation of fish and Norway lobster into the upper and lower codends, respectively, and by lower catch weight in the upper codend of the test codend compared with the standard codend. The decrease in damages may also improve quality indirectly by inflicting...

  1. Detection of Panulirus argus Virus 1 (PaV1) in exported frozen tails of subadult-adult Caribbean spiny lobsters Panulirus argus.

    Science.gov (United States)

    Huchin-Mian, Juan Pablo; Briones-Fourzán, Patricia; Simá-Alvarez, Raúl; Cruz-Quintana, Yanis; Pérez-Vega, Juan Antonio; Lozano-Alvarez, Enrique; Pascual-Jiménez, Cristina; Rodríguez-Canul, Rossanna

    2009-09-23

    The Caribbean spiny lobster Panulirus argus is a valuable fishing resource and the trade in frozen lobster tails is an important industry. However, the presence of the pathogenic virus Panulirus argus Virus 1 (PaV1), which causes systemic infection in P. argus and is particularly lethal to juvenile individuals, has not been previously examined in imported/exported lobster products. We used PCR assays to determine the presence of PaV1 in abdominal muscle tissue of 22 frozen P. argus tails exported from Belize to Mexico. Based on their size, the tails belonged to subadult-adult lobsters. Using specific primers targeted for PaV1 resulted in 11 tails showing a specific 499 bp band. The sequence of positive amplified fragments showed a high similarity to PaV1 (95% identity with GenBank accession no. EF206313.1). Although the pathogenicity of PaV1 was not evaluated in the present study, our results provide the first evidence of PaV1 in frozen lobster tails exported in the seafood industry as well as the first molecular evidence of PaV1 in adult lobsters.

  2. 3-Methylcholanthrene does not induce in vitro xenobiotic metabolism in spiny lobster hepatopancreas, or affect in vivo disposition of benzo(a)pyrene

    Energy Technology Data Exchange (ETDEWEB)

    James, M O; Little, P J

    1984-01-01

    Administration of 3-methylcholanthrene (10 mg/kg) i.m. to spiny lobsters, Panulirus argus, did not cause induction of the cytochrome P-450 content of hepatopancreas microsomes. The rate of oxidation of benzo(a)pyrene or 7-ethoxyresorufin in reductase-fortified preparations of hepatopancreas microsomes was the same for corn oil-treated or 3-methylcholanthrene-treated lobsters. Administration of 3-methylcholanthrene (10 mg/kg) i.m. to spiny lobsters one week prior to an i.v. dose of (/sup 14/C)benzo(a)pyrene (1 mg/kg) did not influence the disposition of the radiolabelled benzo(a)pyrene in lobsters. At one week after the dose of (/sup 14/C)benzo(a)pyrene, approximately 40% of the dose of (/sup 14/C)benzo(a)pyrene remained in the lobsters, regardless of treatment. The digestive tract (hepatopancreas, intestinal contents, stomach and intestine) contained most (86%) of the /sup 14/C remaining in the lobsters.

  3. WATER QUALITY AND ITS EFFECT ON GROWTH AND SURVIVAL RATE OF LOBSTER REARED IN FLOATING NET CAGE IN EKAS BAY, WEST NUSA TENGGARA PROVINCE

    Directory of Open Access Journals (Sweden)

    Muhammad Junaidi

    2015-02-01

    Full Text Available ABSTRACT The development of lobster farming in floating net cage in Ekas Bay caused an environmental degradation such as decrease water quality due to some aquaculture wastes. The purposes of this study were to determine the status of water quality and their effect on growth and survival rate of lobster reared in floating net cages (FNC in the Ekas Bay, West Nusa Tenggara Province. Water sample collection and handling referred to the APHA (1992. Analyses of water quality data were conducted using Principal Component Analysis. Determination of the water quality status of Ekas Bay was performed with STORET system. Multivariate analyses were used to determine the relationship between water quality, growth, and survival rate of lobster reared in FNC. Results showed that Ekas Bay water quality status was categorized in class C (medium contaminated, which exceeded some quality standard parameters such as ammonia (0.3 mg/l, nitrate (0.008 mg/l, and phosphate (0.015 mg/l. During lobster farming activities feeding with trash fish for 270 days, we obtained daily growth rate of  0.74% (lower than normal growth rate of 0.86%, survival rate of 66% (lower than normal survival rate of 86.7%, and feed conversion ratio of 11.15. Ammonia was found as a dominant factor reducing growth  and survival rate of lobster reared in FNC. Keywords: water quality, lobsters, growth, survival, Ekas Bay

  4. New sibling species and new occurrences of squat lobsters (Crustacea, Decapoda from the western Indian Ocean

    Directory of Open Access Journals (Sweden)

    Enrique Macpherson

    2017-08-01

    Full Text Available Numerous specimens of squat lobsters belonging to the families Munididae, Munidopsidae and Eumunididae were collected during several cruises along the eastern coasts of Africa. The study of these specimens revealed the presence of 10 new species (one Eumunida Smith, 1883, eight Munida Leach, 1820 and one Munidopsis Whiteaves, 1874. We describe and illustrate these new species, providing some new data on occurrences and colour patterns for previously described taxa. We have also included molecular data from two mitochondrial markers (16S rRNA and COI to support the taxonomic status of different species. Some deep-sea species show a clear increase in their geographic range distribution. Finally, a key to known species of the genus Munida from the western and central Indian Ocean is also presented.

  5. Kirkpatrick-Baez (KB) and Lobster Eye (LE) Optics for Astronomical and Laboratory Applications

    International Nuclear Information System (INIS)

    Hudec, R.; Hudec, R.

    2010-01-01

    Most of grazing incidence (reflective) X-ray imaging systems used in astronomy and in other (laboratory) applications are based on the Wolter 1 (or modified) arrangement. But there were proposed also other designs and configurations, which are considered for future applications for both in laboratory and (finitely) in space. The Kirkpatrick-Baez (KB) lenses as well as various types of Lobster-Eye (LE) optics and MCP/Micropore optics serve as an example. Analogously to Wolter lenses, the X-rays are mostly reflected twice in these systems to create focal images. The KB systems have already found wide usage in laboratory and synchrotron, both application are reviewed and discussed in detail in this paper. While this paper focuses on future possible applications of non-Wolter grazing incidence systems in space and astronomy, we also discuss in detail applications in other areas of science, where (in contrary to astronomy) some of these systems have demonstrated their advantages

  6. Analysis of marine sediment and lobster hepatopancreas reference materials by instrumental photon activation

    International Nuclear Information System (INIS)

    Landsberger, S.; Davidson, W.F.

    1985-01-01

    By use of instrumental photon activation analysis, twelve trace (As, Ba, Cr, Co, Mn, Ni, Pb, Sb, Sr, U, Zn, and Zr) and eight minor (C, Na, Mg, Co, K, Ca, Tl, and Fe) elements were determined in a certified marine sediment standard reference material as well as eight trace (Mn, Ni, Cu, Zn, As, Sr, Cd, and Pb) and four minor (Na, Mg, Cl, and Ca) elements in a certified marine tissue (lobster hepatopancreas) standard reference material. The precision and accuracy of the present results when compared to the accepted values clearly demonstrate the reliability of this nondestructive technique and its applicability to marine environmental or marine geochemical studies. 24 references, 4 figures, 3 tables

  7. LOBSTER EYE: New approach to monitor GRBs in X-rays

    International Nuclear Information System (INIS)

    Hudec, R.; Hudcova, V.; Inneman, A.; Pina, L.

    2003-01-01

    The detection of X-ray afterglows for the large majority of GRBs allows a novel X-ray experiment to be considered to monitor and to detect GRBs based on their X-ray emission. Such an experiment could provide not only a superior localization accuracy if compared with gamma ray instruments, but probably also a higher rate based on the theoretical assumption that the beaming in gamma rays is narrower if compared with lower energies. We describe and discuss the LOBSTER EYE X-ray telescope project including results of the development and tests of the telescope prototype. Considerations for a space experiment on a small scientific satellite of a Nadezhda type are also presented and discussed. The scientific aspects of such experiment regarding the GRB study and statistics are addressed

  8. Descriptions of Five Species of Scyllarine Lobsters (Crustacea, Decapoda, Scyllaridae in Korea

    Directory of Open Access Journals (Sweden)

    Joo Il Kim

    2013-04-01

    Full Text Available Five scyllarine lobster species, belonging to the family Scyllaridae, are described from Korean waters: Chelarctus cultrifer (Ortmann, 1897, Crenarctus bicuspidatus (De Man, 1905, Galearctus kitanoviriosus (Harada, 1962, G. timidus (Holthuis, 1960, and Petrarctus brevicornis (Holthuis, 1946. Of these, three species, C. bicuspidatus, G. timidus, and P. brevicornis are new to Korean marine carcinological fauna. This report extends the known range of G. timidus to the southern coast of Korea from Taiwan in the East China Sea. Excluding C. bicuspidatus and G. kitanoviriosus, the other three species are relatively rare in Korean waters. They are described herein with color photographs, and a key to the Korean genera and species of Scyllarinae is also presented.

  9. The subcellular localization of natural 210Po in the hepatopancreas of the rock lobster (Jasus lalandii)

    International Nuclear Information System (INIS)

    Heyraud, M.; Dowdle, E.B.; Cherry, R.D.

    1987-01-01

    The subcellular localization of the naturally occurring nuclide 210 Po in the hepatopancreas of the South African rock lobster, Jasus lalandii, has been studied using centrifugation, ultrafiltration and chromatography. Just over half of the 210 Po was found to be associated with a component in the microsomal pellet. Most of the 210 Po was tightly bound to a component of high molecular mass. Dissociation of the 210 Po from this component required incubation with sulphydryl-reducing reagents, after which the 210 Po appeared to associate with a fraction having a molecular mass of 1500 daltons or less. A search for negatively-charged, hydrophobic, sulphur-containing membrane proteins which bind 210 Po is suggested. (author)

  10. Southern high latitude squat lobsters II: description of Uroptychus macquariae sp. nov. from Macquarie Ridge.

    Science.gov (United States)

    Schnabel, Kareen E; Burghardt, Ingo; Ahyong, Shane T

    2017-11-23

    Squat lobsters have only recently been recorded from the Macquarie Ridge, which extends south between New Zealand and Antarctica. Among these, Uroptychus insignis (Henderson, 1885) was recorded for the first time outside the western Indian Ocean, exhibiting only subtle morphological differences. Reexamination of the Macquarie Ridge and Indian Ocean specimens attributed to U. insignis using morphological and molecular data revealed the Macquarie Ridge form to represent a separate species. Subtle but consistent morphological differences are evident and partial CO1 sequence data indicates that the specimens collected on Macquarie Ridge differ from those collected in the Indian Ocean by more than 7%. The Macquarie Ridge species is described herein as Uroptychus macquariae n.sp. Subtle morphological differences between the new species and U. insignis are discussed.

  11. Perspectives of the lobster-eye telescope: The promising types of cosmic X-ray sources

    Science.gov (United States)

    Šimon, V.

    2017-07-01

    We show the astrophysical aspects of observing the X-ray sky with the planned lobster-eye telescope. This instrument is important because it is able to provide wide-field X-ray imaging. For the testing observations, we propose to include also X-ray binaries in which matter transfers onto the compact object (mostly the neutron star). We show the typical features of the long-term X-ray activity of such objects. Observing in the soft X-ray band is the most promising because their X-ray intensity is the highest in this band. Since these X-ray sources tend to concentrate toward the center of our Galaxy, several of them can be present in the field of view of the tested instrument.

  12. Milky hemolymph syndrome (MHS) in spiny lobsters, penaeid shrimp and crabs.

    Science.gov (United States)

    Nunan, Linda M; Poulos, Bonnie T; Navarro, Solangel; Redman, Rita M; Lightner, Donald V

    2010-09-02

    Black tiger shrimp Penaeus monodon, European shore crab Carcinus maenas and spiny lobster Panulirus spp. can be affected by milky hemolymph syndrome (MHS). Four rickettsia-like bacteria (RLB) isolates of MHS originating from 5 geographical areas have been identified to date. The histopathology of the disease was characterized and a multiplex PCR assay was developed for detection of the 4 bacterial isolates. The 16S rRNA gene and 16-23S rRNA intergenic spacer region (ISR) were used to examine the phylogeny of the MHS isolates. Although the pathology of this disease appears similar in the various different hosts, sequencing and examination of the phylogenetic relationships reveal 4 distinct RLB involved in the infection process.

  13. Soft-rigid interaction mechanism towards a lobster-inspired hybrid actuator

    Science.gov (United States)

    Chen, Yaohui; Wan, Fang; Wu, Tong; Song, Chaoyang

    2018-01-01

    Soft pneumatic actuators (SPAs) are intrinsically light-weight, compliant and therefore ideal to directly interact with humans and be implemented into wearable robotic devices. However, they also pose new challenges in describing and sensing their continuous deformation. In this paper, we propose a hybrid actuator design with bio-inspirations from the lobsters, which can generate reconfigurable bending movements through the internal soft chamber interacting with the external rigid shells. This design with joint and link structures enables us to exactly track its bending configurations that previously posed a significant challenge to soft robots. Analytic models are developed to illustrate the soft-rigid interaction mechanism with experimental validation. A robotic glove using hybrid actuators to assist grasping is assembled to illustrate their potentials in safe human-robot interactions. Considering all the design merits, our work presents a practical approach to the design of next-generation robots capable of achieving both good accuracy and compliance.

  14. A new species of squat lobster of the genus Munida (Galatheoidea, Munididae) from the Red Sea

    KAUST Repository

    Macpherson, E.

    2017-08-30

    During a deep-water expedition to the Red Sea in 2013, an unusual specimen of squat lobster belonging to the genus Munida was collected off Thuwal, Saudi Arabia, at a depth of 320 m. This specimen is unique in having the pterygostomial flap visible from the dorsal side, the feature linking it to two eastern Pacific species, M. bapensis Hendrickx, 2000 and M. macrobrachia Hendrickx, 2003. The new species (M. tuerkayi) is readily distinguished from the eastern Pacific species by having the gastric region with numerous instead of less numerous spines, by having sternite 7 with three distinct carinae on each side, and by having the antennular basal article with two distal spines subequal instead of different in size. Munida tuerkayi was found associated with live colonies of the scleractinian coral Eguchipsammia fistula (Alcock, 1902).

  15. Subcellular localization of natural /sup 210/Po in the hepatopancreas of the rock lobster (Jasus lalandii)

    Energy Technology Data Exchange (ETDEWEB)

    Heyraud, M; Dowdle, E B; Cherry, R D

    1987-01-01

    The subcellular localization of the naturally occurring nuclide /sup 210/Po in the hepatopancreas of the South African rock lobster, Jasus lalandii, has been studied using centrifugation, ultrafiltration and chromatography. Just over half of the /sup 210/Po was found to be associated with a component in the microsomal pellet. Most of the /sup 210/Po was tightly bound to a component of high molecular mass. Dissociation of the /sup 210/Po from this component required incubation with sulphydryl-reducing reagents, after which the /sup 210/Po appeared to associate with a fraction having a molecular mass of 1500 daltons or less. A search for negatively-charged, hydrophobic, sulphur-containing membrane proteins which bind /sup 210/Po is suggested.

  16. Isolation and characterization of eight polymorphic microsatellites for the spotted spiny lobster, Panulirus guttatus

    Directory of Open Access Journals (Sweden)

    Nathan Truelove

    2016-01-01

    Full Text Available Microsatellite sequences were isolated from enriched genomic libraries of the spotted spiny lobster, Panulirus guttatus using 454 pyrosequencing. Twenty-nine previously developed polymerase chain reaction primer pairs of Panulirus argus microsatellite loci were also tested for cross-species amplification in Panulirus guttatus. In total, eight consistently amplifying, and polymorphic loci were characterized for 57 individuals collected in the Florida Keys and Bermuda. The number of alleles per locus ranged from 8 to 20 and observed heterozygosities ranged from 0.409 to 0.958. Significant deviations from Hardy–Weinberg equilibrium were found in one locus from Florida and three loci from Bermuda. Quality control testing indicated that all loci were easy to score, highly polymorphic and showed no evidence of linkage disequilibrium. Null alleles were detected in three loci with moderate frequencies ranging from (20% to 22%. These eight microsatellites provide novel molecular markers for future conservation genetics research of P. guttatus.

  17. Stock assessment of the red spiny lobster (Panulirus argus caught in the tropical southwestern Atlantic

    Directory of Open Access Journals (Sweden)

    Humber A Andrade

    2015-03-01

    Full Text Available The stocks of the red spiny lobster (Panulirus argus (Latreille, 1804 in the Caribbean and in the Brazilian coast are of considerable economic importance. There are important genetic differences between the Brazilian and Caribbean populations, which support separated stock assessment. The present study provides an assessment of the Brazilian stock of P. argus using a biomass dynamic model based on a Bayesian approach. Assuming that the catch per unit effort is a valid index of relative abundance, the results of the analysis indicate that stocks have been heavily overexploited since the 1980s. The present-day scenario is pessimistic, and there is evidence that the stock may be close to collapse.

  18. Chilean jagged lobster, Projasus bahamondei, in the southeastern Pacific Ocean: current state of knowledge

    Directory of Open Access Journals (Sweden)

    Patricio M Arana

    2014-03-01

    Full Text Available The Chilean jagged lobster (Projasus bahamondei is a deep-water crustacean (175-550 m occurring in certain areas of the southeastern Pacific Ocean, including the Nazca Ridge, Desventuradas Islands, the Juan Fernandez archipelago and ridge, and the continental slope off the central coast of Chile. This review describes the taxonomic status, geographical and bathymetric distribution, some biological aspects and habitat characteristics of this species. Additionally, both artisanal and industrial exploitation attempts made within the region are detailed, as well as fishing operation results, chemical composition, different elaboration procedures and the destination of the catch. The main objectives of this review are to contribute to the knowledge of P. bahamondei as a component of the deep-sea ecosystem and to highlight its importance as a potential fishery resource.

  19. Study of Phenotypic Correlations between Morphologic Characters and Body Parameters at River Male Lobsters (Astacus Fluviatilis

    Directory of Open Access Journals (Sweden)

    Marian Bura

    2010-10-01

    Full Text Available The body measurements was made on 20 males of river lobster (Astacus fluviatilis or Astacus astacus. The lobsters on witch the study was made had an average total length of body of 12.72 cm ±0.19 cm (formed from: 6.07±0.10cm the length of cefalothorax, 4.73 ±0.10 cm the length of abdomen and 1.91 ±0.07 cm length of telson, and a body weight of 55.70±3.07 g. the males present a length of antennas of 8.53±0.34 cm, a feelers of 2.20±0.05 cm, and the stems of the eyes of 0.51±0.02 cm. The body of males present a average width of 3.35±0.07 cm at level of cefalothorax, and 2.40±0.05 cm at abdomen level. Average deepness of cefalothorax was 2.85±0.07cm, and abdomen deepness of 1.34±0.03cm. The 5 pairs of periopodes had an average length of 10.91±0.42 cm, 6.06±0.22 cm, 7.21±0.21 cm, 6.57±0.16 cm and 5.85±0.15cm. The average length of pleopods was at first pears of 2.00±0.06 cm, at second pair of 2.11±0.05 cm, at third of 1.85±0.05 cm, at fourth of 1.73±0.04 cm and at fifth pair of 1.55±0.04 cm.

  20. Utilization of Shrimp Skin Waste (Sea Lobster) As Raw Material for the Membrane Filtration

    International Nuclear Information System (INIS)

    Rupiasih, Ni Nyoman; Windari, Putri; Sumadiyasa, Made; Suyanto, Hery

    2017-01-01

    In view of the increasing littering of the sea banks by shells of crustaceans, a study was carried out to investigate the extraction and characterization of chitosan from skin waste of sea lobster i.e. ‘Bamboo Lobster’ ( Panulirus versicolor ). Chitosan was extracted using conventional methods such as pretreatment, demineralization, deprotienization, and deacetylation. The result showed that the degree of deacetylation of chitosan obtained is 70.02%. The FTIR spectra of the chitosan gave a characteristic of –NH 2 band at 3447 cm –1 and carbonyl group band at 1655 cm −1 . This chitosan has been used to prepare membrane. The chitosan membrane 2% has been prepared using phase inversion method with precipitation by solvent evaporation. The membranes were characterized by FTIR spectrophotometer, Nova 1200e using BJH method, and filtration method. The results show that thickness of the membrane is about 134 μm. The FTIR spectra show that functional groups present in the membrane are -NH, -CH, C=O, and -OH. Using BJH method obtained that the pore diameter is 3.382 nm with pore density is 8.95 x 10 5 pores/m 3 . By filtration method obtained that pure water flux (PWF) of the membrane are 386.662 and 489.627 1/m 2 .h at pressure 80-85 kPa and 90-100 kPa, respectively. These results show that skin waste of sea lobster was discovered as a raw material to prepare chitosan membrane. The membrane obtained is belonged to mesoporous group which may use in microfiltration process. (paper)

  1. The spatial and temporal patterns of odors sampled by lobsters and crabs in a turbulent plume.

    Science.gov (United States)

    Reidenbach, Matthew A; Koehl, M A R

    2011-09-15

    Odors are dispersed across aquatic habitats by turbulent water flow as filamentous, intermittent plumes. Many crustaceans sniff (take discrete samples of ambient water and the odors it carries) by flicking their olfactory antennules. We used planar laser-induced fluorescence to investigate how flicking antennules of different morphologies (long antennules of spiny lobsters, Panulirus argus; short antennules of blue crabs, Callinectes sapidus) sample fluctuating odor signals at different positions in a turbulent odor plume in a flume to determine whether the patterns of concentrations captured can provide information about an animal's position relative to the odor source. Lobster antennules intercept odors during a greater percentage of flicks and encounter higher peak concentrations than do crab antennules, but because crabs flick at higher frequency, the duration of odor-free gaps between encountered odor pulses is similar. For flicking antennules there were longer time gaps between odor encounters as the downstream distance to the odor source decreases, but shorter gaps along the plume centerline than near the edge. In contrast to the case for antennule flicking, almost all odor-free gaps were <500 ms at all positions in the plume if concentration was measured continuously at the same height as the antennules. Variance in concentration is lower and mean concentration is greater near the substratum, where leg chemosensors continuously sample the plume, than in the water where antennules sniff. Concentrations sampled by legs increase as an animal nears an odor source, but decrease for antennules. Both legs and antennules encounter higher concentrations near the centerline than at the edge of the plume.

  2. Black Humour Spaces in Cinema and Literature: Yorgos Lanthimos' The Lobster and Tom McCarthy's Satin Island

    Directory of Open Access Journals (Sweden)

    Vincenzo Maggitti

    2016-11-01

    Full Text Available Maggitti’s essay is focused on two different expressions of black humour in today’s film and literature. After commenting on a recent proposal, by the British writer Jonathan Coe, on the whereabouts of contemporary humour, the author examines a film  (The Lobster by YorgosLanthimos and a novel (Satin Island by T. McCarthy, both portraying the present world through humorous lenses, with a disrespectful attitude to an ecologically correct behaviour. In The Lobster hunting is claimed a universal role in man to animal relation whereas Tom McCarthy turns environmental disasters into acts of worthy ecologism. In his approach to humour, Maggitti draws on its anthropological turn as its most estranging function.

  3. Molecular evidence for the Southern Hemisphere origin and deep-sea diversification of spiny lobsters (Crustacea: Decapoda: Palinuridae).

    Science.gov (United States)

    Tsang, L M; Chan, T-Y; Cheung, M K; Chu, K H

    2009-05-01

    Spiny lobsters (family Palinuridae) are economically important marine animals that have been the subject of a considerable amount of research. However, the phylogeny of this group remains disputed. Morphological analyses have not been able to resolve the relationships of the various members of the group, and no agreement has yet been reached on its phylogeny as indicated by the different gene trees reported to date. In the present study, we attempt to reconstruct the phylogeny of Palinuridae and its allies using sequences from three nuclear protein-coding genes (phosphoenolpyruvate carboxykinase, sodium-potassium ATPase alpha-subunit and histone 3). The inferred topology receives strong nodal support for most of the branches. The family Palinuridae is found to be paraphyletic with the polyphyletic Synaxidae nested within it. Stridentes forms a monophyletic assemblage, indicating that the stridulating sound producing organ evolved only once in the spiny lobsters. By contrast, Silentes is paraphyletic, as Palinurellus is more closely related to Stridentes than to other Silentes genera. The three genera restricted to the southern high latitudes (Jasus, Projasus and Sagmariasus) constitute the basal lineages in the spiny lobsters, suggesting a Southern Hemisphere origin for the group. Subsequent diversification appears to have been driven by the closure of the Tethys Sea and the formation of the Antarctic circumpolar current, which isolated the northern and southern taxa. Contrary to an earlier hypothesis that postulated evolution from a deep-sea ancestral stock, the shallow-water genus Panulirus is the basal taxon in Stridentes, while the deep-sea genera Puerulus and Linuparus are found to be derived. This indicates that the spiny lobsters invaded deep-sea habitats from the shallower water rocky reefs and then radiated. Our results suggest that Synaxidae is not a valid family, and should be considered to be synonymous with Palinuridae. We also found that the

  4. Defense through sensory inactivation: sea hare ink reduces sensory and motor responses of spiny lobsters to food odors.

    Science.gov (United States)

    Love-Chezem, Tiffany; Aggio, Juan F; Derby, Charles D

    2013-04-15

    Antipredator defenses are ubiquitous and diverse. Ink secretion of sea hares (Aplysia) is an antipredator defense acting through the chemical senses of predators by different mechanisms. The most common mechanism is ink acting as an unpalatable repellent. Less common is ink secretion acting as a decoy (phagomimic) that misdirects predators' attacks. In this study, we tested another possible mechanism--sensory inactivation--in which ink inactivates the predator's reception of food odors associated with would-be prey. We tested this hypothesis using spiny lobsters, Panulirus argus, as model predators. Ink secretion is composed of two glandular products, one being opaline, a viscous substance containing concentrations of hundreds of millimolar of total free amino acids. Opaline sticks to antennules, mouthparts and other chemosensory appendages of lobsters, physically blocking access of food odors to the predator's chemosensors, or over-stimulating (short term) and adapting (long term) the chemosensors. We tested the sensory inactivation hypotheses by treating the antennules with opaline and mimics of its physical and/or chemical properties. We compared the effects of these treatments on responses to a food odor for chemoreceptor neurons in isolated antennules, as a measure of effect on chemosensory input, and for antennular motor responses of intact lobsters, as a measure of effect on chemically driven motor behavior. Our results indicate that opaline reduces the output of chemosensors by physically blocking reception of and response to food odors, and this has an impact on motor responses of lobsters. This is the first experimental demonstration of inactivation of peripheral sensors as an antipredatory defense.

  5. Spiny lobsters use urine-borne olfactory signaling and physical aggressive behaviors to influence social status of conspecifics.

    Science.gov (United States)

    Shabani, Shkelzen; Kamio, Michiya; Derby, Charles D

    2009-08-01

    Decapod crustaceans, like many other animals, engage in agonistic behaviors that enhance their ability to compete for resources with conspecifics. These agonistic behaviors include the release of chemical signals as well as physical aggressive and submissive behaviors. In this study, we report that Caribbean spiny lobsters, Panulirus argus, use both urine-borne chemical signaling and physical aggressive behaviors during interactions with conspecifics, and that these agonistic behaviors can influence the behavior and eventual social status of the interactants. Spiny lobsters that engaged primarily in physical aggressive behaviors became dominant, whereas spiny lobsters that received these physical aggressive behaviors responded with avoidance behaviors and became subordinates. Dominant animals frequently released urine during social interactions, more than when they were not in contact with subordinates and more than when they were not paired with another animal. Subordinates released urine significantly less often than dominants, and no more than when not paired. Preventing release of urine by catheterizing the animals resulted in an increase in the number and duration of physical interactions, and this increase was primarily driven by dominants initiating interactions through physical aggressive behaviors. Introducing urine from one of the catheterized animals into an aquarium reduced physical aggressive behavior by dominant animals to normal levels. Urine-borne signals alone were capable of inducing avoidance behaviors from solitary spiny lobsters in both laboratory and field conditions. We conclude that urine serves as a chemical signal that communicates social status to the interactants. Ablation experiments showed that that these urine signals are detected primarily by aesthetasc sensilla of the olfactory pathway.

  6. Spinning in different directions: western rock lobster larval condition varies with eddy polarity, but does their diet?

    OpenAIRE

    O'Rorke, R.; Jeffs, A. G.; Wang, M.; Waite, A. M.; Beckley, L. E.; Lavery, S. D.

    2015-01-01

    Larvae of the western rock lobster (Panulirus cygnus) that occur in the south-east Indian Ocean offshore of Western Australia have been found to be in poorer nutritional condition in anticyclonic compared with cyclonic mesoscale eddies. The reason for this is unknown, but culture-based experiments have shown that diet composition and water temperature are key determinants of phyllosoma health and survival. Whether differences in prey composition are the cause of poor phyllosoma co...

  7. Cadmium bound to metal rich granules and exoskeleton from Gammarus pulex causes increased gut lipid peroxidation in zebrafish following single dietary exposure

    Energy Technology Data Exchange (ETDEWEB)

    Khan, F.R., E-mail: fkhan@wlu.ca [Nutritional Sciences Division, King' s College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH (United Kingdom); Bury, N.R.; Hogstrand, C. [Nutritional Sciences Division, King' s College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH (United Kingdom)

    2010-01-31

    There has been a growing interest in establishing how the sub-cellular distribution of metals in macro-invertebrate prey affects metal trophic bioavailability and toxicity. In this study, the crustacean Gammarus pulex was exposed to 300 {mu}g Cd l{sup -1} spiked with {sup 109}Cd for 13 days, from which the two principal metal containing sub-cellular fractions, the metallothionein-like protein (MTLP) and the metal rich granule and exoskeleton (MRG + exo) were isolated. These fractions were produced at equal metal content, incorporated into gelatin and fed to zebrafish as a single meal; assimilation efficiency (AE), carcass and gut tissue metal concentrations and gut lipid peroxidative damage measured as malondialdehyde (MDA) were assessed. The AE of cadmium bound to the MTLP fraction was 32.1 {+-} 5.6% which was significantly greater than the AE of MRG + exo bound Cd, 13.0 {+-} 2.1% (p < 0.05). Of the metal retained by the fish at 72 h post-feeding, 94% of MTLP-Cd had been incorporated into the carcass, whereas a significant proportion (46%) of MRG + exo-Cd, although assimilated, appeared to remain associated with intestinal tissue. However, this did not translate into a gut tissue concentration difference with 6.8 {+-} 1.2 ng Cd g{sup -1} in fish fed MTLP-Cd compared to 9.5 {+-} 1.4 ng Cd g{sup -1} in fish fed MRG + exo fraction. Both feeds led to significantly increased MDA levels compared to the control group (gelatin only feed), but MRG + exo feed caused significantly more oxidative damage than the MTLP feed (p < 0.01). Thus, MTLP-Cd is more bioavailable than the cadmium bound to granules and exoskeleton, but it was the latter fraction, largely considered as having limited bioavailability, that appeared to exert a greater localised oxidative injury to the digestive tract of zebrafish.

  8. UV-irradiation and leaching in water reduce the toxicity of imidacloprid-contaminated leaves to the aquatic leaf-shredding amphipod Gammarus fossarum.

    Science.gov (United States)

    Englert, Dominic; Zubrod, Jochen P; Neubauer, Christoph; Schulz, Ralf; Bundschuh, Mirco

    2018-05-01

    Systemic neonicotinoid insecticides such as imidacloprid are increasingly applied against insect pest infestations on forest trees. However, leaves falling from treated trees may reach nearby surface waters and potentially represent a neonicotinoid exposure source for aquatic invertebrates. Given imidacloprid's susceptibility towards photolysis and high water solubility, it was hypothesized that the leaves' toxicity might be modulated by UV-irradiation during decay on the forest floor, or by leaching and re-mobilization of the insecticide from leaves within the aquatic ecosystem. To test these hypotheses, the amphipod shredder Gammarus fossarum was fed (over 7 d; n = 30) with imidacloprid-contaminated black alder (Alnus glutinosa) leaves that had either been pre-treated (i.e., leached) in water for up to 7 d or UV-irradiated for 1 d (at intensities relevant during autumn in Central Europe) followed by a leaching duration of 1 d. Gammarids' feeding rate, serving as sublethal response variable, was reduced by up to 80% when consuming non-pretreated imidacloprid-contaminated leaves compared to imidacloprid-free leaves. Moreover, both leaching of imidacloprid from leaves (for 7 d) as well as UV-irradiation reduced the leaves' imidacloprid load (by 46 and 90%) thereby mitigating the effects on gammarids' feeding rate to levels comparable to the respective imidacloprid-free controls. Therefore, natural processes, such as UV-irradiation and re-mobilization of foliar insecticide residues in water, might be considered when evaluating the risks systemic insecticide applications in forests might pose for aquatic organisms in nearby streams. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Evidence of low dose effects of the antidepressant fluoxetine and the fungicide prochloraz on the behavior of the keystone freshwater invertebrate Gammarus pulex.

    Science.gov (United States)

    De Castro-Català, N; Muñoz, I; Riera, J L; Ford, A T

    2017-12-01

    In recent years, behavior-related endpoints have been proposed as rapid and reliable ecotoxicological tools for risk assessment. In particular, the use of detritivores to test the toxicity of pollutants through feeding is currently becoming a well-known method. Experiments combining feeding with other behavioral endpoints can provide relevant information about direct and indirect toxicological effects of chemicals. We carried out a feeding experiment with the shredder Gammarus pulex in order to detect indirect (through leaf conditioning) and direct effects (through water exposure) of two pollutants at environmentally relevant concentrations: the fungicide prochloraz (6 μg/L) and the antidepressant fluoxetine (100 ng/L). Prochloraz inhibited fungal growth on leaves, but it did not affect either the microbial breakdown rates or the C:N ratio of the leaves. Individuals of G. pulex that were fed with treated leaves presented lower consumption rates, not only those fed with prochloraz-treated leaves, but also those fed with fluoxetine-treated leaves, and those fed with the mixture-treated leaves. Mixed-effects models revealed that the swimming velocity of the amphipods after the experiment was modulated by the exposure to fluoxetine, and also by the exposure to prochloraz. We demonstrate that both the antidepressant and the fungicide may cause significant sublethal effects at low concentrations. The combination of behavioral endpoints together with the application of mixed models provided a useful tool for early detection of the effects of toxicity mixtures in freshwater ecosystems. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  10. Differential uptake and oxidative stress response in zebrafish fed a single dose of the principal copper and zinc enriched sub-cellular fractions of Gammarus pulex

    International Nuclear Information System (INIS)

    Khan, Farhan R.; Bury, Nicolas R.; Hogstrand, Christer

    2010-01-01

    The sub-cellular compartmentalisation of trace metals and its effect on trophic transfer and toxicity in the aquatic food chain has been a subject of growing interest. In the present study, the crustacean Gammarus pulex was exposed to either 11 μg Cu l -1 , added solely as the enriched stable isotope 65 Cu, or 660 μg Zn l -1 , radiolabeled with 2MBq 65 Zn, for 16 days. Post-exposure the heat stable cytosol containing metallothionein-like proteins (MTLP) and a combined granular and exoskeletal (MRG + exo) fractions were isolated by differential centrifugation, incorporated into gelatin and fed to zebrafish as a single meal. Assimilation efficiency (AE) and intestinal lipid peroxidation, as malondialdehyde (MDA) were measured. There was a significant difference (p 65 Cu, although the results pointed towards greater bioavailability of the MTLP fraction compared to MRG + exo during the slow elimination phase (24-72 h) these results were not significant (p = 0.155). Neither zinc feed provoked a lipid peroxidation response in the intestinal tissue of zebrafish compared to control fish (gelatin fed), but both 65 Cu labeled feeds did. The greater effect was exerted by the MRG + exo (2.96 ± 0.29 nmol MDA mg protein -1 ) feed which three-fold greater than control (p -1 , p 109 Cd labeled G. pulex fractions were fed to zebrafish. Thus it appears that when a metal (Cu or Cd) has the potential to cause cytotoxicity via lipid peroxidation, a feed consisting of a largely unavailable fraction (MRG + exo) causes a greater intestinal stress response than the more bioavailable (MTLP) feed.

  11. Multibiomarker assessment of cerium dioxide nanoparticle (nCeO{sub 2}) sublethal effects on two freshwater invertebrates, Dreissena polymorpha and Gammarus roeseli

    Energy Technology Data Exchange (ETDEWEB)

    Garaud, M. [Université de Lorraine, CNRS UMR 7360, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Campus Bridoux, Rue du Général Delestraint, 57070 Metz (France); International Consortium for the Environmental Implications of Nanotechnology (iCEINT), Aix en Provence (France); Trapp, J.; Devin, S.; Cossu-Leguille, C.; Pain-Devin, S.; Felten, V. [Université de Lorraine, CNRS UMR 7360, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Campus Bridoux, Rue du Général Delestraint, 57070 Metz (France); Giamberini, L., E-mail: laure.giamberini@univ-lorraine.fr [Université de Lorraine, CNRS UMR 7360, Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC), Campus Bridoux, Rue du Général Delestraint, 57070 Metz (France); International Consortium for the Environmental Implications of Nanotechnology (iCEINT), Aix en Provence (France)

    2015-01-15

    Highlights: • Gammarids and mussels both accumulated significant amount of waterborne nCeO{sub 2}. • nCeO{sub 2} decreased catalase, lysosomal system size and lipoperoxidation in mussels. • nCeO{sub 2} could exert antioxidant protecting activity in mussels. • In contrast with mussels, no effects of nCeO{sub 2} were observed on Gammarids. - Abstract: Cerium nanoparticles (nCeO{sub 2}) are widely used in everyday products, as fuel and paint additives. Meanwhile, very few studies on nCeO{sub 2} sublethal effects on aquatic organisms are available. We tried to fill this knowledge gap by investigating short-term effects of nCeO{sub 2} at environmentally realistic concentrations on two freshwater invertebrates; the amphipod Gammarus roeseli and the bivalve Dreissena polymorpha, using an integrated multibiomarker approach to detect early adverse effects of nCeO{sub 2} on organism biology. Differences in the behaviour of the organisms and of nanoparticles in the water column led to differential nCeO{sub 2} bioaccumulations, G. roeseli accumulating more cerium than D. polymorpha. Exposure to nCeO{sub 2} led to decreases in the size of the lysosomal system, catalase activity and lipoperoxidation in mussel digestive glands that could result from nCeO{sub 2} antioxidant properties, but also negatively impacted haemolymph ion concentrations. At the same time, no strong adverse effects of nCeO{sub 2} could be observed on G. roeseli. Further experiments will be necessary to confirm the absence of severe nCeO{sub 2} adverse effects in long-term environmentally realistic conditions.

  12. Influence of conspecific and heterospecific aggregation cues and alarm odors on shelter choice by syntopic spiny lobsters.

    Science.gov (United States)

    Briones-Fourzán, Patricia; Ramírez-Zaldívar, Eunice; Lozano-Alvarez, Enrique

    2008-10-01

    In spiny lobsters, conspecific scents ("aggregation cues") may mediate gregarious diurnal sheltering, but scents from injured conspecifics ("alarm odors") may elicit avoidance behavior. In laboratory experiments, individuals of two coexisting species, Panulirus guttatus (a reef-obligate) and P. argus (a temporary reef-dweller), significantly chose shelters emanating conspecific aggregation cues and responded randomly to shelters emanating heterospecific aggregation cues. However, despite evidence that the two species perceived each other's alarm odors to a similar extent, P. guttatus responded randomly to shelters emanating either conspecific or heterospecific alarm odors, whereas P. argus significantly avoided both. This differential influence of alarm odors likely reflects interspecific differences in life history, sociality, and behavior. The less social, reef-obligate P. guttatus lobsters forage close to their reef dens, into which they retract deeply upon perception of risk. This cryptic behavior may offset the need to avoid conspecific (and heterospecific) alarm odors. In contrast, avoidance of conspecific alarm odors by P. argus is consistent with its ontogenetic habitat shifts and greater sociality. Furthermore, because reef-dwelling P. argus lobsters forage across open areas away from the reef, an ability to avoid alarm odors from P. guttatus upon returning to their reef dens may increase their fitness.

  13. Settlement and juvenile habitat of the European spiny lobster Palinurus elephas (Crustacea: Decapoda: Palinuridae in the western Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    David Díaz

    2001-12-01

    Full Text Available Settlement characteristics, like timing, depth, microhabitat and density of European spiny lobster Palinurus elephas are described for the very first time. Regular SCUBA-diving surveys were conducted from July 1998 to January 2000 on rocky bottoms of three different geologic origins to assess substratum-dependent differences in recruitment density. Settlement of pueruli took place in June-July, a few weeks after sea surface temperature started to rise. The highest density of juveniles was found at 10-15 m depth. Most spiny lobsters settled in limestone rocks, into empty holes of the date mussel Lithophaga lithophaga, which provided daytime refuge. As they grew, individuals were increasingly found in larger holes and crevices of the rock surface. Sizes were estimated from photographs taken at night when the animals were actively foraging. The smallest observed individuals measured 7.5-8 mm carapace length (CL, but they reached 15-18 mm CL at the end of October. The consequences of our results for the management of the spiny lobster populations in the northwestern Mediterranean are summarily discussed.

  14. Reef Sound as an Orientation Cue for Shoreward Migration by Pueruli of the Rock Lobster, Jasus edwardsii.

    Science.gov (United States)

    Hinojosa, Ivan A; Green, Bridget S; Gardner, Caleb; Hesse, Jan; Stanley, Jenni A; Jeffs, Andrew G

    2016-01-01

    The post-larval or puerulus stage of spiny, or rock, lobsters (Palinuridae) swim many kilometres from open oceans into coastal waters where they subsequently settle. The orientation cues used by the puerulus for this migration are unclear, but are presumed to be critical to finding a place to settle. Understanding this process may help explain the biological processes of dispersal and settlement, and be useful for developing realistic dispersal models. In this study, we examined the use of reef sound as an orientation cue by the puerulus stage of the southern rock lobster, Jasus edwardsii. Experiments were conducted using in situ binary choice chambers together with replayed recording of underwater reef sound. The experiment was conducted in a sandy lagoon under varying wind conditions. A significant proportion of puerulus (69%) swam towards the reef sound in calm wind conditions. However, in windy conditions (>25 m s-1) the orientation behaviour appeared to be less consistent with the inclusion of these results, reducing the overall proportion of pueruli that swam towards the reef sound (59.3%). These results resolve previous speculation that underwater reef sound is used as an orientation cue in the shoreward migration of the puerulus of spiny lobsters, and suggest that sea surface winds may moderate the ability of migrating pueruli to use this cue to locate coastal reef habitat to settle. Underwater sound may increase the chance of successful settlement and survival of this valuable species.

  15. The emergence of lobsters: phylogenetic relationships, morphological evolution and divergence time comparisons of an ancient group (decapoda: achelata, astacidea, glypheidea, polychelida).

    Science.gov (United States)

    Bracken-Grissom, Heather D; Ahyong, Shane T; Wilkinson, Richard D; Feldmann, Rodney M; Schweitzer, Carrie E; Breinholt, Jesse W; Bendall, Matthew; Palero, Ferran; Chan, Tin-Yam; Felder, Darryl L; Robles, Rafael; Chu, Ka-Hou; Tsang, Ling-Ming; Kim, Dohyup; Martin, Joel W; Crandall, Keith A

    2014-07-01

    Lobsters are a ubiquitous and economically important group of decapod crustaceans that include the infraorders Polychelida, Glypheidea, Astacidea and Achelata. They include familiar forms such as the spiny, slipper, clawed lobsters and crayfish and unfamiliar forms such as the deep-sea and "living fossil" species. The high degree of morphological diversity among these infraorders has led to a dynamic classification and conflicting hypotheses of evolutionary relationships. In this study, we estimated phylogenetic relationships among the major groups of all lobster families and 94% of the genera using six genes (mitochondrial and nuclear) and 195 morphological characters across 173 species of lobsters for the most comprehensive sampling to date. Lobsters were recovered as a non-monophyletic assemblage in the combined (molecular + morphology) analysis. All families were monophyletic, with the exception of Cambaridae, and 7 of 79 genera were recovered as poly- or paraphyletic. A rich fossil history coupled with dense taxon coverage allowed us to estimate and compare divergence times and origins of major lineages using two drastically different approaches. Age priors were constructed and/or included based on fossil age information or fossil discovery, age, and extant species count data. Results from the two approaches were largely congruent across deep to shallow taxonomic divergences across major lineages. The origin of the first lobster-like decapod (Polychelida) was estimated in the Devonian (∼409-372 Ma) with all infraorders present in the Carboniferous (∼353-318 Ma). Fossil calibration subsampling studies examined the influence of sampling density (number of fossils) and placement (deep, middle, and shallow) on divergence time estimates. Results from our study suggest including at least 1 fossil per 10 operational taxonomic units (OTUs) in divergence dating analyses. [Dating; decapods; divergence; lobsters; molecular; morphology; phylogenetics.]. © The

  16. Myospora metanephrops (n. g., n. sp.) from marine lobsters and a proposal for erection of a new order and family (Crustaceacida; Myosporidae) in the Class Marinosporidia (Phylum Microsporidia).

    Science.gov (United States)

    Stentiford, G D; Bateman, K S; Small, H J; Moss, J; Shields, J D; Reece, K S; Tuck, I

    2010-10-01

    In this study we describe, the first microsporidian parasite from nephropid lobsters. Metanephrops challengeri were captured from an important marine fishery situated off the south coast of New Zealand. Infected lobsters displayed an unusual external appearance and were lethargic. Histology was used to demonstrate replacement of skeletal and other muscles by merogonic and sporogonic stages of the parasite, while transmission electron microscopy revealed the presence of diplokaryotic meronts, sporonts, sporoblasts and spore stages, all in direct contact with the host sarcoplasm. Analysis of the ssrDNA gene sequence from the lobster microsporidian suggested a close affinity with Thelohania butleri, a morphologically dissimilar microsporidian from marine shrimps. Whilst morphological features of the lobster parasite are consistent with members of the family Nosematidae, molecular data place the parasite closer to members of the family Thelohanidae. Due to the contradiction between morphological and molecular taxonomic data, we propose the erection of a new genus in which the lobster parasite is the type species (Myospora metanephrops). Furthermore, we recommend the erection of a new family (Myosporidae) and a new order (Crustaceacida) to contain this genus. The taxonomic framework presented could be further applied to the re-classification of existing members of the Phylum Microsporidia. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  17. Reproductive biology of galatheoid and chirostyloid (Crustacea: Decapoda) squat lobsters from the Gulf of Mexico.

    Science.gov (United States)

    Kilgour, Morgan J; Shirley, Thomas C

    2014-01-16

    Reproductive timing, fecundity, and average egg sizes were examined for galatheoid and chirostyloid squat lobster collections from the Gulf of Mexico. While congeners did not always significantly differ in egg size or timing, each genus had a unique average egg diameter size which may indicate whether the developing embryos will be lecithotrophic or planktotrophic larvae. The eggs of Eumunididae, Galatheidae, and Munididae were more numerous and smaller than the larger and less abundant eggs of Chirostylidae and Munidopsidae. With the exception of members of the Munididae, members of genera within the same family had distinct egg diameters. Ovigerous females were significantly larger than non-ovigerous females in some species (i.e., Uroptychus nitidus, Munida forceps, Galacantha spinosa, Munidopsis abbreviata, M. alaminos, M., erinacea, M. robusta, M. sigsbei, and M. simplex). Munidopsis erinacea and Munida affinis males were significantly larger than females; the reverse was true for Munidopsis robusta and Munidopsis simplex. All other species studied did not have a significant difference between males and females. The spatial and bathymetric ranges for many species are extended in this study from prior reports. Seasonality of reproduction was evident in few species, but this may be a result of limited sample sizes.

  18. Testing and modelling of the SVOM MXT narrow field lobster-eye telescope

    Science.gov (United States)

    Feldman, Charlotte; Pearson, James; Willingale, Richard; Sykes, John; Drumm, Paul; Houghton, Paul; Bicknell, Chris; Osborne, Julian; Martindale, Adrian; O'Brien, Paul; Fairbend, Ray; Schyns, Emile; Petit, Sylvain; Roudot, Romain; Mercier, Karine; Le Duigou, Jean-Michel; Gotz, Diego

    2017-08-01

    The Space-based multi-band astronomical Variable Objects Monitor (SVOM) is a French-Chinese space mission to be launched in 2021 with the goal of studying gamma-ray bursts, the most powerful stellar explosions in the Universe. The Microchannel X-ray Telescope (MXT) on-board SVOM, is an X-ray focusing telescope with a detector-limited field of view of ˜1 square° , working in the 0.2-10 keV energy band. The MXT is a narrow-field-optimised lobster eye telescope, designed to promptly detect and accurately locate gamma-ray bursts afterglows. The breadboard MXT optic comprises of an array of square pore micro pore optics (MPOs) which are slumped to a spherical radius of 2 m giving a focal length of 1 m and an intrinsic field of view of ˜6° . We present details of the baseline design and results from the ongoing X-ray tests of the breadboard and structural thermal model MPOs performed at the University of Leicester and at Panter. In addition, we present details of modelling and analysis which reveals the factors that limit the angular resolution, characteristics of the point spread function and the efficiency and collecting area of the currently available MPOs.

  19. Irreversible adsorption of atmospheric helium on olivine: A lobster pot analogy

    Science.gov (United States)

    Protin, Marie; Blard, Pierre-Henri; Marrocchi, Yves; Mathon, François

    2016-04-01

    This study reports new experimental results that demonstrate that large amounts of atmospheric helium may be adsorbed onto the surfaces of olivine grains. This behavior is surface-area-related in that this contamination preferentially affects grains that are smaller than 125 μm in size. One of the most striking results of our study is that in vacuo heating at 900 °C for 15 min is not sufficient to completely remove the atmospheric contamination. This suggests that the adsorption of helium may involve high-energy trapping of helium through irreversible anomalous adsorption. This trapping process of helium can thus be compared to a ;lobster pot; adsorption: atmospheric helium easily gets in, but hardly gets out. While this type of behavior has previously been reported for heavy noble gases (Ar, Kr, Xe), this is the first time that it has been observed for helium. Adsorption of helium has, until now, generally been considered to be negligible on silicate surfaces. Our findings have significant implications for helium and noble gas analysis of natural silicate samples, such as for cosmic-ray exposure dating or noble gas characterization of extraterrestrial material. Analytical procedures in future studies should be adapted in order to avoid this contamination. The results of this study also allow us to propose an alternative explanation for previously described matrix loss of cosmogenic 3He.

  20. Variation in cheliped form in two species of squat lobsters (Decapoda: Anomura from Chile

    Directory of Open Access Journals (Sweden)

    Aníbal H. Lezcano

    2015-09-01

    Full Text Available AbstractThe current study describes the variation in cheliped form of two species of squat lobsters that inhabit the continental margin off Chile: Cervimunida johni and Pleuroncodes monodon. We compared their cheliped form in the context of the reproductive strategy. The general tendency of form variation of both species is similar: chelipeds change, on average, from longer and narrower pollex with short manus to a relatively shorter and wider pollex with longer manus from small to large individuals, respectively. The degree of cheliped arching was greater in males than in females of similar carapace length, and only C. johni males showed fully arched morphology. The allometric trajectories (cheliped shape vs. carapace length were largely aligned with vectors of mean shape difference in both species. Cheliped form variation of C. johni (extended mate-guarding resembles the cheliped morphology reported for the related species Munida rugosa more than P. monodon (short mate-guarding. Our results are consistent with previous finding and suggest that the cheliped form variation (from straight and slender to a fully arched morphology is, or has been, subject to sexual selection through male-male competition for mates.

  1. Innate Immunity in Lobsters: Partial Purification and Characterization of a Panulirus cygnus Anti-A Lectin.

    Science.gov (United States)

    Flower, Robert L P

    2012-01-01

    A lectin detected in haemolymph from the Australian spiny lobster Panulirus cygnus agglutinated human ABO Group A cells to a higher titre than Group O or B. The lectin also agglutinated rat and sheep erythrocytes, with reactivity with rat erythrocytes strongly enhanced by treatment with the proteolytic enzyme papain, an observation consistent with reactivity via a glycolipid. The lectin, purified by affinity chromatography on fixed rat-erythrocyte stroma, was inhibited equally by N-acetylglucosamine and N-acetylgalactosamine. Comparison of data from gel filtration of haemolymph (behaving as a 1,800,000 Da macromolecule), and polyacrylamide gel electrophoresis of purified lectin (a single 67,000 Da band), suggested that in haemolymph the lecin was a multimer. The purified anti-A lectin autoprecipitated unless the storage solution contained chaotropic inhibitors (125 mmol/L sucrose: 500 mmol/L urea). The properties of this anti-A lectin and other similar lectins are consistent with a role in innate immunity in these invertebrates.

  2. Decadal variability in growth of the Caribbean spiny lobster Panulirus argus (Decapoda: Paniluridae in Cuban waters

    Directory of Open Access Journals (Sweden)

    Maria Estela de León

    2005-09-01

    Full Text Available Annual von Bertalanffy growth parameters of the Caribbean spiny lobster (Panulirus argus in Cuban waters were estimated from a long term study (40 years by length-based methods ELEFAN and the new version of SLCA. Data of around 800 000 lobsters (with carapace length ranging 14 to 199mm were randomly sampled in artificial shelters (a non selective fishing gear very common in the lobster fishery, through the field monitory program established for this species since 1963 in 14 localities of southwestern Cuban shelf. The software ELEFAN showed problems to converge in an optimal combination of the instantaneous growth coefficient (K and the asymptotic length (L8 of the von Bertalanffy equation, whereas the new SLCA software produced value estimates of K between 0.20 and 0.27 year-1 and values of L8 between 177 and 190 mm carapace length, all within the range reported in the literature. The standardized anomalies of both parameters showed the presence of cycles along the analyzed time series. Decadal variability in growth parameters was revealed through the spectral analysis indicating cycles of 16 and 20 years for K and of 16 years for L8. The incidence of some factors such as biomass and temperature that modulate growth in this crustacean was explored, using a nonlinear multiple regression model. These combined factors explained 33% and 69% of the variability of K and L8 respectively. The growth coefficient appeared to be maximum with annual mean sea surface temperature of 28.1º C and the largest L 8is reached at a annual men biomass level of 23 000 t. These results should be the basis to understand the Cuban lobster population dynamics. Rev. Biol. Trop. 53(3-4: 475-486. Epub 2005 Oct 3.Los parámetros de crecimiento anuales para la langosta espinosa del Caribe (Panulirus argus en aguas cubanas se estimaron para una serie de 40 años de datos de composición por longitud, a través de los métodos indirectos basados en la talla ELEFAN y el nuevo

  3. Hydrodynamic, non-photic modulation of biorhythms in the Norway lobster, Nephrops norvegicus (L.)

    Science.gov (United States)

    Aguzzi, J.; Puig, P.; Company, J. B.

    2009-03-01

    Data on biological rhythms of the Norway lobster Nephrops norvegicus (L.) are compared with new findings on inertial currents, a non-photic geophysical hydrodynamic fluctuation. Laboratory experiments on animal endogenous cardiac activity and locomotor rhythms using individuals from the middle slope (400-600 m depth) of the Mediterranean Sea revealed a consistent proportion of ultradian 18-h animals (20.6% and 12.0% of the studied cases for cardiac and locomotor tests, respectively). This characteristic, not reported in similar experiments with individuals from shallower depths (20-200 m) in the Atlantic Ocean, was initially considered meaningless from an ecological point of view. However, a close comparison with in situ oceanographic measurements over 1 year revealed a clear relationship between inertial current fluctuations and the observed 18-h behavioural and physiological rhythms. We propose a novel scenario involving potential non-photic (i.e. hydrodynamic) modulation of Nephrops biorhythms, and suggest that this may provide a paradigm for other benthic species in deep-water areas.

  4. Inter-cohort growth for three tropical resources: tilapia, octopus and lobster.

    Science.gov (United States)

    Velázquez-Abunader, Iván; Gómez-Muñoz, Victor Manuel; Salas, Silvia; Ruiz-Velazco, Javier M J

    2015-09-01

    Growth parameters are an important component for the stock assessment of exploited aquatic species. However, it is often difficult to apply direct methods to estimate growth and to analyse the differences between males and females, particularly in tropical areas. The objective of this study was to analyse the inter-cohort growth of three tropical resources and discuss the possible fisheries management implications. A simple method was used to compare individual growth curves obtained from length frequency distribution analysis, illustrated by case studies of three tropical species from different aquatic environments: tilapia (Oreochromis aureus), red octopus (Octopus maya) and the Caribbean spiny lobster (Panulirus argus). The analysis undertaken compared the size distribution of males and females of a given cohort through modal progression analysis. The technique used proved to be useful for highlighting the differences in growth between females and males of a specific cohort. The potential effect of extrinsic and intrinsic factors on the organism's development as reflected in the size distribution of the cohorts is discussed.

  5. Response of inorganic materials to laser - plasma EUV radiation focused with a lobster eye collector

    Science.gov (United States)

    Bartnik, Andrzej; Fiedorowicz, Henryk; Jarocki, Roman; Kostecki, Jerzy; Szczurek, Miroslaw; Havlikova, Radka; Pína, Ladislav; Švéda, Libor; Inneman, Adolf

    2007-05-01

    A single photon of EUV radiation carries enough energy to break any chemical bond or excite electrons from inner atomic shells. It means that the radiation regardless of its intensity can modify chemical structure of molecules. It is the reason that the radiation even with low intensity can cause fragmentation of long chains of organic materials and desorption of small parts from their surface. In this work interaction of EUV radiation with inorganic materials was investigated. Different inorganic samples were irradiated with a 10 Hz laser - plasma EUV source based on a gas puff target. The radiation was focused on a sample surface using a lobster eye collector. Radiation fluence at the surface reached 30 mJ/cm2 within a wavelength range 7 - 20 nm. In most cases there was no surface damage even after several minutes of irradiation. In some cases there could be noticed discolouration of an irradiated surface or evidences of thermal effects. In most cases however luminescent and scattered radiation was observed. The luminescent radiation was emitted in different wavelength ranges. It was recorded in a visible range of radiation and also in a wide wavelength range including UV, VUV and EUV. The radiation was especially intense in a case of non-metallic chemical compounds.

  6. Virtual dissection and lifestyle of a 165 -million-year-old female polychelidan lobster.

    Science.gov (United States)

    Jauvion, Clément; Audo, Denis; Charbonnier, Sylvain; Vannier, Jean

    2016-03-01

    Polychelidan lobsters are fascinating crustaceans that were known as fossils before being discovered in the deep-sea. They differ from other crustaceans by having four to five pairs of claws. Although recent palaeontological studies have clarified the systematics and phylogeny of the group, the biology of extant polychelidans and--first of all--their anatomy are poorly documented. Numerous aspects of the evolutionary history of the group remain obscure, in particular, how and when polychelidans colonized the deep-sea and became restricted to it. Surprisingly, the biology of extant polychelidans and the anatomy of all species, fossil and recent, are poorly documented. Here, X-ray microtomography (XTM), applied to an exceptionally well-preserved specimen from the La Voulte Lagerstätte, reveals for the first time vital aspects of the external and internal morphology of Voulteryon parvulus (Eryonidae), a 165-million-year-old polychelidan: 1) its mouthparts (maxillae and maxillipeds), 2) its digestive tract and 3) its reproductive organs. Comparisons with dissected specimens clearly identify this specimen as a female with mature ovaries. This set of new information offers new insights into the feeding and reproductive habits of Mesozoic polychelidans. Contrasting with other Jurassic polychelidans that lived in shallow-water environments, V. parvulus spawned in, and probably inhabited, relatively deep-water environments, as do the survivors of the group. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Survival, food consumption and growth of Norway lobster (Nephrops norvegicus) kept in laboratory conditions.

    Science.gov (United States)

    Mente, Elena

    2010-09-01

    Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals. The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L., 1758) under laboratory conditions. The aim of the present study was to examine food consumption, growth and physiology of the Norway lobster N. norvegicus under laboratory conditions. N. norvegicus (15 g wet weight) were distributed into 1001 tanks consisting of five numbered compartments each. They were fed the experimental diets (frozen mussels and pellets) for a period of 6 months. A group of starved Nephrops was stocked and fasted for 8 months. Although Nephrops grew well when fed the frozen mussels diet, feeding on a dry pellet feed was unsatisfactory. The starvation group, despite the fact that showed the highest mortality (50%), exhibited a remarkable tolerance to the lack of food supply. The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets. The deviations from the mussel's diet for asparagine, alanine and glutamic acid suggest a deficiency of these amino acids in this diet. The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids, except for arginine, proline and glycine. The present study contributes to the improvement of our knowledge on nutritional requirements of the above species. © 2010 ISZS, Blackwell Publishing and IOZ/CAS.

  8. Inter-cohort growth for three tropical resources: tilapia, octopus and lobster

    Directory of Open Access Journals (Sweden)

    Iván Velázquez-Abunader

    2015-09-01

    Full Text Available Growth parameters are an important component for the stock assessment of exploited aquatic species. However, it is often difficult to apply direct methods to estimate growth and to analyse the differences between males and females, particularly in tropical areas. The objective of this study was to analyse the inter-cohort growth of three tropical resources and discuss the possible fisheries management implications. A simple method was used to compare individual growth curves obtained from length frequency distribution analysis, illustrated by case studies of three tropical species from different aquatic environments: tilapia (Oreochromis aureus,red octopus (Octopus mayaand the Caribbean spiny lobster (Panulirus argus.The analysis undertaken compared the size distribution of males and females of a given cohort through modal progression analysis. The technique used proved to be useful for highlighting the differences in growth between females and males of a specific cohort. The potential effect of extrinsic and intrinsic factors on the organism's development as reflected in the size distribution of the cohorts is discussed.

  9. Lead, cadmium and chromium in raw and boiled portions of Norway lobster.

    Science.gov (United States)

    Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Abete, Maria Cesarina; Tarasco, Renata; Amorena, Michele

    2014-01-01

    Lead, cadmium and chromium levels were determined in different raw and boiled portions of Norway lobster caught in the central Adriatic Sea (Italy). In raw specimens, the lowest concentrations were always detected in the white meat. Lead and cadmium content in the edible portion never exceeded the maximum levels set by European legislation. The highest cadmium and chromium values (0.47 ± 0.04 and 0.62 ± 0.13 mg/kg wet weight, respectively) were detected in the brown meat, while the highest lead concentrations were found in the exoskeleton (0.21 ± 0.01 mg/kg wet weight). Also, the boiled samples showed the lowest metal levels in the white meat, even if a significant increase (p < 0.01) was found for lead and cadmium compared to the corresponding raw portions. Among metals, chromium showed the highest concentrations in both raw and boiled portions, but up to now, the European legislation did not envisage any limits in seafood.

  10. Seasonal variations in activity concentrations of 99Tc and 137Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea.

    Science.gov (United States)

    Copplestone, D; Jackson, D; Hartnoll, R G; Johnson, M S; McDonald, P; Wood, N

    2004-01-01

    Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of (99)Tc, as a result of the treatment of previously stored waste, with consequent increases in (99)Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of (99)Tc and (137)Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of (99)Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of (99)Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg(-1) (fresh weight (fw)) in crabs and 124 to 216 Bq kg(-1) (fw) in lobsters, with no observed seasonal variations. Activity concentrations of (137)Cs in both crab and lobster were lower, ranging from lobster meat (fw). A statistically significant increase in activity concentrations of (137)Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves during the active

  11. Seasonal variations in activity concentrations of 99Tc and 137Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea

    International Nuclear Information System (INIS)

    Copplestone, D.; Jackson, D.; Hartnoll, R.G.; Johnson, M.S.; McDonald, P.; Wood, N.

    2004-01-01

    Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of 99 Tc, as a result of the treatment of previously stored waste, with consequent increases in 99 Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of 99 Tc and 137 Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of 99 Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of 99 Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg -1 (fresh weight (fw)) in crabs and 124 to 216 Bq kg -1 (fw) in lobsters, with no observed seasonal variations. Activity concentrations of 137 Cs in both crab and lobster were lower, ranging from -1 for crab meat (fw) and -1 for lobster meat (fw). A statistically significant increase in activity concentrations of 137 Cs in the meat was observed in the summer months for both crab and lobster. The cause has not been investigated but may be related to the laying down of energy reserves

  12. Seasonal variations in activity concentrations of {sup 99}Tc and {sup 137}Cs in the edible meat fraction of crabs and lobsters from the central Irish Sea

    Energy Technology Data Exchange (ETDEWEB)

    Copplestone, D. E-mail: copplest@liv.ac.uk; Jackson, D.; Hartnoll, R.G.; Johnson, M.S.; McDonald, P.; Wood, N

    2004-07-01

    Discharges of most radionuclides into the Irish Sea from the BNFL site at Sellafield have decreased over the past 20 years or so. For a few radionuclides, however, discharges have peaked more recently. Notably, operation of the Enhanced Actinide Removal Plant (EARP) since 1994 has led to an increase in discharges of {sup 99}Tc, as a result of the treatment of previously stored waste, with consequent increases in {sup 99}Tc activity concentrations in a number of marine species, particularly in crustaceans such as lobsters. Previous research has considered the significance of factors such as sex and body weight on radionuclide concentrations. The current project set out to investigate whether seasonal variations in radionuclide concentrations in crabs and lobsters occur, with particular emphasis on the dynamics of {sup 99}Tc and {sup 137}Cs. Organisms were obtained from a site off the Isle of Man, where radionuclide concentrations were measurable but the site was sufficiently distant from Sellafield that the radionuclides were well mixed in the water column and not likely to be influenced by the pulsed nature of discharges of {sup 99}Tc. Crab and lobster samples were collected monthly, between February 2000 and February 2001. Fifteen or 16 individuals (evenly split as male and female) of each species were collected on each occasion. Seawater samples were also collected over the 12-month period. Activity concentrations of {sup 99}Tc in the edible meat fraction (both brown and white meat) ranged from 0.23 to 2.46 Bq kg{sup -1} (fresh weight (fw)) in crabs and 124 to 216 Bq kg{sup -1} (fw) in lobsters, with no observed seasonal variations. Activity concentrations of {sup 137}Cs in both crab and lobster were lower, ranging from <0.16 to 0.85 Bq kg{sup -1} for crab meat (fw) and <0.3 to 3.3 Bq kg{sup -1} for lobster meat (fw). A statistically significant increase in activity concentrations of {sup 137}Cs in the meat was observed in the summer months for both crab and

  13. Effect of a synthetic drilling fluid (IPAR) on antioxidant enzymes and peroxisome proliferation in the American lobster, Homarsus americanus

    Energy Technology Data Exchange (ETDEWEB)

    Hamoutene, D.; Payne, J.F.; Andrews, C.; Wells, J.; Guiney, J.

    2004-07-01

    The acute, sublethal toxicity of a synthetic paraffinic drilling fluid (IPAR) was examined in this study which exposed 2 sets of 14 lobsters to the substance. Synthetic-based muds (SBMs) make up the fluid component of drilling muds along with water-based muds (WBMs) and oil-based muds (OBMs). Although SBMs are proposed to replace OBMs, little is known about their environmental impact. IPAR, an ultra-pure isoalkane with no aromatics or sulphur compounds, is currently used in the Newfoundland offshore. This study examined the effect of IPAR on benthic crustacean because most of the wastes discharged from drilling platforms sediment quickly and the impact is greatest on benthic animals. The lobsters were injected with 1 mL of IPAR every 3 days, to a maximum of 5 mL. They were also exposed to very high levels of the fluid, which would not be expected under field conditions. Different aspects of lipid and protein metabolism were monitored along with the effect of IPAR on peroxisome proliferations and various serum and organ enzymes. The study showed that even at the high dose administered to the lobsters, the isoalkane mixture had no influence on peroxisome proliferation. Increased amounts of protein was found in claw muscles, but no increase was observed in gills, hepatopancreas or heart, suggesting no adverse impact of IPAR. A slight increase was also noted in serum aminotransferases. The study results are in agreement with the hypothesis that IPAR has little or no ecotoxicological potential. 32 refs., 3 tabs., 2 figs.

  14. Effect of a synthetic drilling fluid (IPAR) on antioxidant enzymes and peroxisome proliferation in the American lobster, Homarsus americanus

    International Nuclear Information System (INIS)

    Hamoutene, D.; Payne, J.F.; Andrews, C.; Wells, J.; Guiney, J.

    2004-01-01

    The acute, sublethal toxicity of a synthetic paraffinic drilling fluid (IPAR) was examined in this study which exposed 2 sets of 14 lobsters to the substance. Synthetic-based muds (SBMs) make up the fluid component of drilling muds along with water-based muds (WBMs) and oil-based muds (OBMs). Although SBMs are proposed to replace OBMs, little is known about their environmental impact. IPAR, an ultra-pure isoalkane with no aromatics or sulphur compounds, is currently used in the Newfoundland offshore. This study examined the effect of IPAR on benthic crustacean because most of the wastes discharged from drilling platforms sediment quickly and the impact is greatest on benthic animals. The lobsters were injected with 1 mL of IPAR every 3 days, to a maximum of 5 mL. They were also exposed to very high levels of the fluid, which would not be expected under field conditions. Different aspects of lipid and protein metabolism were monitored along with the effect of IPAR on peroxisome proliferations and various serum and organ enzymes. The study showed that even at the high dose administered to the lobsters, the isoalkane mixture had no influence on peroxisome proliferation. Increased amounts of protein was found in claw muscles, but no increase was observed in gills, hepatopancreas or heart, suggesting no adverse impact of IPAR. A slight increase was also noted in serum aminotransferases. The study results are in agreement with the hypothesis that IPAR has little or no ecotoxicological potential. 32 refs., 3 tabs., 2 figs

  15. Spatial trends of co-planar contaminants in lobster digestive gland from the Gulf of St. Lawrence

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, W.L.; Arsenault, J.T.; Comeau, M. [Department of Fisheries and Oceans, Moncton, NB (Canada)

    1997-05-01

    A study on spatial trends of contaminants in Canadian marine biota was conducted between 1993 and 1995. Lobster digestive glands were sampled from eight locations on the Gulf of St. Lawrence near New Brunswick and Nova Scotia. A total of 15 gland samples were analysed for dioxin, furan and co-planar PCB congeners. The five highest concentrations measured (5.8-12 pg/g wet-weight) were from samples taken from within the barrier island of Miramichi Bay in New Brunswick. This is an area of municipal and industrial development where contamination levels in marine biota is a continuing local concern.

  16. Characterization of chitinolytic bacteria and histological aspects of Shell Disease Syndrome in European spiny lobsters (Palinurus elephas) (Fabricius 1787).

    Science.gov (United States)

    Mancuso, M; Costanzo, M T; Maricchiolo, G; Gristina, M; Zaccone, R; Cuccu, D; Genovese, L

    2010-07-01

    The present research reports the first description of Shell Disease Syndrome in European spiny lobsters Palinurus elephas (Fabricius 1787), which occurred in an experimental aquaculture facility in Sicily (Italy). Both bacterial characterization and histopathological examination of the exoskeleton at site of lesions was carried out. Infected specimens showed tail fan erosions, and in one case uropod ulceration and complete loss of periods. Identified species included: Listonella anguillarum 50.5%, Vibrio parahaemolyticus 27.5% and Vibrio alginolyticus 22%. Microscopic evaluation of lesions indicate the presence of inflammatory responses, which include melanization and pseudomembrane formation, similar to those described for other crustaceans affected by SDS. (c) 2010 Elsevier Inc. All rights reserved.

  17. Miocene squat lobsters (Decapoda, Anomura, Galatheoidea) of the Central Paratethys - a review, with description of a new species of Munidopsis.

    Science.gov (United States)

    Hyžný, M; Gašparič, R; Robins, C M; Schlögl, J

    2014-10-01

    All squat lobsters of the families Galatheidae, Munididae and Munidopsidae from the Miocene of the Central Paratethys are reviewed taxonomically. Based on additional observations emended diagnoses are provided for Agononida cerovensis and Galathea weinfurteri , from the Lower and Middle Miocene, respectively. Munidopsis is represented by two species in the study area; additional data for M. lieskovensis from the Lower Miocene of Slovakia are presented and a new species, M. palmuelleri , from the Middle Miocene of Slovenia is erected. Implications for palaeoenvironmental reconstructions are briefly discussed for each taxon.

  18. Population biology and feeding habits of the nephropid lobster Metanephrops thomsoni (Bate, 1888) in the East China Sea.

    Science.gov (United States)

    Choi, Jung Hwa; Kim, Jung Nyun; Kim, Mi Hyang; Chang, Dae Soo; Yoo, Joon Taek; Kim, Jin Koo

    2008-07-01

    Population biology and feeding habits of the nephropidlobsterMetanephrops thomsoni (Bate) was studied from a field survey sampled with bottom trawls in the East China Sea. The female/male ratio was 1.06:1. Three size-class groups were discriminated for both sexes, which may correspond to one to three year-old cohorts. The average stage fecundity was 471 in each brood. Larger than two-year-size-class females are multi broods during the breeding season. Gut analysis showed that this lobster is a common camivore and mainly consume crustaceans and fishes, regardless of sex and carapace length size.

  19. A bio-economic application to the Cape Rock Lobster resource using a delay difference modelling approach

    Directory of Open Access Journals (Sweden)

    E Roos

    2004-06-01

    Full Text Available In many species, like the Cape Rock Lobster (Jasus lalandii, the life cycles of males and females differ. This may motivate the use of two-sex models in a stock-assessment analysis. It is also true for this resource, that juveniles do not reach sexual maturity immediately. Therefore a delay-difference model is appropriate. In this study we follow a bio-economic approach and use a two-sex delay-difference model to determine a maximum economic yield strategy. Thus we determine an economic optimum steady state solution at which to harvest this resource subject to the biological constraints of the species.

  20. Effects of complex hydrodynamic processes on the horizontal and vertical distribution of Tc-99 in the Irish Sea

    International Nuclear Information System (INIS)

    Olbert, Agnieszka I.; Hartnett, Michael; Dabrowski, Tomasz; Kelleher, Kevin

    2010-01-01

    The increased discharge of Tc-99 from the Sellafield plant following the commissioning of the Enhance Actinide Removal Plant in 1994 was reflected in higher Tc-99 activity concentrations over much of the Irish Sea. The presence of this radionuclide in the marine environment is of concern not only because of its long half life but also high bio-concentration factor in commercially valuable species, such Norway lobster (Nephrops norvegicus) and common lobster (Homarus gammarus). Accurate predictions of the transport, and spatial and temporal distributions of Tc-99 in the Irish Sea have important environmental and commercial implications. In this study, transport of the Tc-99 material was simulated in order to develop an increased understanding of long-term horizontal and vertical distributions. In particular, impact of seasonal hydrodynamic features such as the summer stratification on the surface-to-bottom Tc-99 ratio was of interest. Also, material retention mechanisms within the western Irish Sea were explored and flushing rates under various release conditions and meteorological forcing were estimated. The results show that highest vertical gradients are observed between June and July in the deepest regions of the North Channel and the western Irish Sea where radionuclide-rich saline-poor water overlays radionuclide-poor saline-rich Atlantic water masses. Strong correlation between top-to-bottom ratio of Tc-99 and strength of stratification was found. Flushing studies demonstrate that as the stratification intensifies, residence times within the western Irish Sea increase. In stratified waters of the gyre Tc-99 material is flushed out from the upper layer much quicker than from the bottom zone. The research also shows that in the gyre the biologically active upper layers above the thermocline are likely to contain higher concentrations than the near-bed region. Long-term horizontal and vertical distributions as determined in this study provide a basis for

  1. Effects of complex hydrodynamic processes on the horizontal and vertical distribution of Tc-99 in the Irish Sea

    Energy Technology Data Exchange (ETDEWEB)

    Olbert, Agnieszka I., E-mail: indiana.olbert@nuigalway.ie [Civil Engineering Department, Environmental Change Institute, National University of Ireland, Galway (Ireland); Hartnett, Michael; Dabrowski, Tomasz [Civil Engineering Department, Environmental Change Institute, National University of Ireland, Galway (Ireland); Kelleher, Kevin [Radiological Protection Institute of Ireland, 3 Clonskeagh Square, Clonskeagh Road, Dublin 14 (Ireland)

    2010-12-01

    The increased discharge of Tc-99 from the Sellafield plant following the commissioning of the Enhance Actinide Removal Plant in 1994 was reflected in higher Tc-99 activity concentrations over much of the Irish Sea. The presence of this radionuclide in the marine environment is of concern not only because of its long half life but also high bio-concentration factor in commercially valuable species, such Norway lobster (Nephrops norvegicus) and common lobster (Homarus gammarus). Accurate predictions of the transport, and spatial and temporal distributions of Tc-99 in the Irish Sea have important environmental and commercial implications. In this study, transport of the Tc-99 material was simulated in order to develop an increased understanding of long-term horizontal and vertical distributions. In particular, impact of seasonal hydrodynamic features such as the summer stratification on the surface-to-bottom Tc-99 ratio was of interest. Also, material retention mechanisms within the western Irish Sea were explored and flushing rates under various release conditions and meteorological forcing were estimated. The results show that highest vertical gradients are observed between June and July in the deepest regions of the North Channel and the western Irish Sea where radionuclide-rich saline-poor water overlays radionuclide-poor saline-rich Atlantic water masses. Strong correlation between top-to-bottom ratio of Tc-99 and strength of stratification was found. Flushing studies demonstrate that as the stratification intensifies, residence times within the western Irish Sea increase. In stratified waters of the gyre Tc-99 material is flushed out from the upper layer much quicker than from the bottom zone. The research also shows that in the gyre the biologically active upper layers above the thermocline are likely to contain higher concentrations than the near-bed region. Long-term horizontal and vertical distributions as determined in this study provide a basis for

  2. Resistance to starvation of first-stage juveniles of the Caribbean spiny lobster

    Directory of Open Access Journals (Sweden)

    Alí Espinosa-Magaña

    2017-01-01

    Full Text Available The non-feeding postlarva (puerulus of spiny lobsters actively swims from the open ocean to the coastal habitats where it settles and molts to the first-stage juvenile (JI. Because pueruli use much of their energy reserves swimming and preparing for the post-settlement molt, the survival of JIs presumably depends on resuming feeding as soon as possible. To test this hypothesis, the resistance to starvation of JIs of the Caribbean spiny lobster, Panulirus argus, was evaluated by measuring their point-of-no-return (PNR, minimum time of initial starvation preventing recovery after later feeding and point-of-reserve-saturation (PRS, minimum time of initial feeding allowing for food-independent development through the rest of the molting cycle in a warm and a cold season. Each experiment consisted of eight groups: a continuously fed control (FC group, a continuously starved control (SC group, and six groups subjected to differential periods of either initial starvation and subsequent feeding (PNR experiments or initial feeding and subsequent starvation (PSR experiments. No JIs molted under continuous absence of food (SC. In both PNR experiments (temperature in warm season: 29.79 ± 0.07°C, mean ± 95% CI; in cold season: 25.63 ± 0.12°C mortality increased sharply after 9 d of initial starvation and intermolt periods increased with period of initial starvation, but were longer in the cold season. The PNR50 was longer in the warm season (12.1 ± 1.2 d, mean ± 95% CI than in the cold season (9.5 ± 2.1 d. In PRS experiments (temperature in warm season: 29.54 ± 0.07 °C; in cold season: 26.20 ± 0.12 °C, JIs that molted did so near the end of the feeding period; all JIs initially fed for up to 6 d succumbed, and no JIs molted after 13 d of starvation despite having fed previously. The PRS50 did not differ between the cold (13.1 ± 0.7 d and warm seasons (12.1 ± 1.1 d. JIs of P. argus exhibit a remarkable resistance to

  3. Proline transport by brush-border membrane vesicles of lobster antennal glands

    International Nuclear Information System (INIS)

    Behnke, R.D.; Wong, R.K.; Huse, S.M.; Reshkin, S.J.; Ahearn, G.A.

    1990-01-01

    Purified brush-border membrane vesicles (BBMV) of lobster antennal gland labyrinth and bladder were separately formed by a magnesium precipitation technique. L-[3H]proline uptake was stimulated by a transmembrane NaCl gradient [outside (o) greater than inside (i)] to a greater extent in BBMV from labyrinth than those from the bladder. Detailed study of the labyrinth proline-transport processes revealed a specific dependence on NaCl, with negligible stimulatory effects by NaSCN, Na-gluconate, or KCl. A transmembrane proton gradient (o greater than i) was without stimulatory effect on proline transport. A transmembrane potential difference alone, in the presence of equilibrated NaCl and L-[3H]proline, led to net influx of the labeled amino acid, suggesting that the uptake process was electrogenic and capable of bringing about the net transfer of positive charge to the vesicle interior. Although a transmembrane Na gradient alone, in the presence of equilibrated Cl and L-[3H]proline, was able to bring about the net influx of the amino acid, a transmembrane Cl gradient alone under Na- and L-[3H]proline-equilibrated conditions was not, suggesting that only the Na gradient could energize the carrier process through cotransport, while the anion served an essential activating role. Proline influx by these vesicles occurred by the combination of at least one saturable Michaelis-Menten carrier system (apparent Kt = 0.37 mM; apparent JM = 1.19 nmol.mg protein-1.10 s-1) and apparent diffusion (P = 0.33 nmol.mg protein-1.10 s-1.mM-1). Static head analysis of the transport process suggested a cotransport stoichiometry of 2 Na:1 proline with essential activation by Cl ion

  4. Proton-stimulated Cl-HCO3 antiport by basolateral membrane vesicles of lobster hepatopancreas

    International Nuclear Information System (INIS)

    Ahearn, G.A.; Grover, M.L.; Tsuji, R.T.; Clay, L.P.

    1987-01-01

    Purified epithelial basolateral membrane vesicles were prepared from lobster hepatopancreas by sorbitol gradient centrifugation. Na+-K+-adenosinetriphosphatase, alkaline phosphatase, and cytochrome-c oxidase enzyme activities in the final membrane preparation were enriched 9.6-, 1.4-, and 0.4-fold, respectively, compared with their activities in the original tissue homogenate. Vesicle osmotic reactivity was demonstrated using 60-min equilibrium 36 Cl uptake experiments at a variety of transmembrane osmotic gradients. 36 Cl uptake into vesicles preloaded with HCO 3 was significantly greater than into vesicles lacking HCO 3 . This exchange process was stimulated by a transmembrane proton gradient (internal pH greater than external pH). Proton-gradient-dependent Cl-HCO 3 exchange was potential sensitive and stimulated by an electrically negative vesicle interior. 36 Cl influx (4-s exposures) into HCO 3 -loaded vesicles occurred by the combination of 4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid sensitive, carrier-mediated transfer and apparent diffusion. 36 Cl influx was a hyperbolic function of both internal [HCO 3 ] and internal [Cl]. The two internal anions displayed a 100-fold difference in apparent affinity constants with HCO 3 being strongly preferred. 36 Cl influx was stimulated more by preloaded monovalent than by divalent anions. Na was an inhibitor of proton-dependent anion antiport, whereas K had no effect. A model for HCl-HCO 3 antiport is suggested that employs combined transmembrane concentration gradients of Cl and HCO 3 to power anion exchange and transfer protons against a concentration gradient

  5. Study of Zn, Cd, and Pb Adsorption Using Chitin Extracted from Lobsters from Oman Sea

    Directory of Open Access Journals (Sweden)

    Alireza Sardashti

    2015-10-01

    Full Text Available Lobster shells from Konarak Port were collected in October 2002, purified, and dried for the purposes of the present study. Chitin was extracted from the shellsusing the common chemical processes of demineralization, proteinzation, and decolonization, beforepurificationwith 1% CH3COOH and 1% NaCl to obatin an extract containing 12% (w/w chitin. Chitin composition was determined using FT-IR, X-Ray powder diffraction, BET, and C.H.N.S analysis. The FT-IR spectrum of the extracted chitin was corresponded well to the Merck standard one, indicating that it is a linear polymer of N-acetyl-D- glucosamine on which metal ions can be adsorbed. Kinetic study of chitin’s reaction with Zn+2 at pH=6.75 and an ionic strength of 0.02 M indicated that adsorption equilibrium was reached within six hours of mixing. Adsorption Langmuir isotherms for a solution of Zn+2, Cd+2, and Pb+2 ions at an initial concentration of 2×10‒3 M were determined for an ionic strenght of 0.02 M, different pH levels, and at ambient temparature using the discontinued in-pot method. The maximum amounts of metal ions adsorbed on chitin at pH= 6.75 were measured to be 0.119 mol/kg for Cd+2, 0.714 mol/kg for Zn+2, and 1.630 mol/Kg for Pb+2. The overdyeing graphs, Cs= f (pH, show that the adsorption capacity of chitin is influenced by such factors as pH, reaction time, metal ion concantration, and adsorbent particle size. Thus, chitin as a non-toxic natural polymer may be highly recommended for water detoxification from heavy metal ions.

  6. Comparing the catch composition, profitability and discard survival from different trammel net designs targeting common spiny lobster (Palinurus elephas) in a Mediterranean fishery.

    Science.gov (United States)

    Catanese, Gaetano; Hinz, Hilmar; Gil, Maria Del Mar; Palmer, Miquel; Breen, Michael; Mira, Antoni; Pastor, Elena; Grau, Amalia; Campos-Candela, Andrea; Koleva, Elka; Grau, Antoni Maria; Morales-Nin, Beatriz

    2018-01-01

    In the Balearic Islands, different trammel net designs have been adopted to promote fisheries sustainability and reduce discards. Here, we compare the catch performance of three trammel net designs targeting the spiny lobster Palinurus elephas in terms of biomass, species composition and revenue from commercial catches and discards. Designs differ in the netting fiber type (standard polyfilament, PMF, or a new polyethylene multi-monofilament, MMF) and the use of a guarding net or greca , a mesh piece intended to reduce discards. Catches were surveyed by an on-board observer from 1,550 netting walls corresponding to 70 nets. The number of marketable species captured indicated that the lobster trammel net fishery has multiple targets, which contribute significantly to the total revenue. The discarded species ranged from habitat-forming species to elasmobranches, but the magnitude of gear-habitat interactions on the long term dynamics of benthos remains unclear. No relevant differences in revenue and weight of discards were detected after Bayesian analyses. However, the species composition of discards was different when using greca . Interestingly, high immediate survival was found for discarded undersized lobsters, while a seven day survival assessment, using captive observation, gave an asymptotic estimate of survival probability as 0.64 (95% CI [0.54-0.76]). Therefore, it is recommended that it would be beneficial for this stock if an exemption from the EU landing obligation regulation was sought for undersized lobsters in the Balearic trammel net fishery.

  7. COMPARATIVE ELECTRON-MICROSCOPY AND IMAGE-ANALYSIS OF OXY-HEMOCYANIN AND DEOXY-HEMOCYANIN FROM THE SPINY LOBSTER PANULIRUS-INTERRUPTUS

    NARCIS (Netherlands)

    DEHAAS, F; VANBREEMEN, JFL; BOEKEMA, EJ; KEEGSTRA, W; VANBRUGGEN, EFJ

    Structural differences between oxy-hemocyanin and deoxy-hemocyanin from the spiny lobster P. interruptus were studied by electron microscopy and image analysis of negatively stained preparations. Projections of the hexameric P. interruptus hemocyanin from electron microscopy were compared with

  8. Function and functional groupings of the complex mouth apparatus of the squat lobsters Munida sarsi Huus and M. tenuimana G.O. Sars (Crustacea: Decapoda)

    DEFF Research Database (Denmark)

    Garm, A; Høeg, J T

    2001-01-01

    Like all other decapods, the anomuran squat lobsters Munida sarsi and M. tenuimana have a mouth apparatus composed of six pairs of mouthparts plus labrum and paragnaths (upper and lower lips). To study the functional significance of this complexity, we examined the mouthparts with scanning electron...

  9. Recovery by the Norway lobster Nephrops norvegicus (L.) from the physiological stresses of trawling: Influence of season and live-storage position

    DEFF Research Database (Denmark)

    Lund, H. S.; Wang, T.; Chang, E. S.

    2009-01-01

    Live Norway lobsters (Nephrops norvegicus L.) were trawled at depths of 30 to 55 m off the coast of Jutland (Denmark) in late winter (March) and in summer (August) in 2006. Water temperatures at the bottom and surface of the sea were 7 °C and 2 °C during the winter, and 12 °C and 21 °C in the sum......Live Norway lobsters (Nephrops norvegicus L.) were trawled at depths of 30 to 55 m off the coast of Jutland (Denmark) in late winter (March) and in summer (August) in 2006. Water temperatures at the bottom and surface of the sea were 7 °C and 2 °C during the winter, and 12 °C and 21 °C...... in the summer, respectively. The recovery of specific physiological and metabolic variables from the intense stresses associated with capture (trawling and air-exposure during sorting) was followed in seawater at 5 °C in winter or 18 °C in summer. Recovery was compared in lobsters held individually in two......-base status. In winter, a potential metabolic lactic acidosis was compensated by a marked respiratory alkalosis, with significantly increased haemolymph pH and decreased CO2 total content and partial pressure. These effects disappeared gradually over 96 h. Summer lobsters showed combined metabolic...

  10. New policies may call for new approaches: the case of the Swedish Norway lobster (Nephrops norvegicus) fisheries in the Kattegat and Skagerrak

    DEFF Research Database (Denmark)

    Hornborg, Sara; Jonsson, Patrik; Sköld, Mattias

    2017-01-01

    -evaluations of current practice are important as a basis for management actions. The Swedish fishery for Norway lobster (Nephrops norvegicus) in the Kattegat–Skagerrak area provides an interesting case study of relevance to emerging policies. Sprung from an unbalance in available fish- and Nephrops quotas...

  11. The use of at-sea-sampling data to dissociate environmental variability in Norway lobster (Nephrops norvegicus) catches to improve resource efficiency

    DEFF Research Database (Denmark)

    Feekings, Jordan P.; Christensen, Asbjørn; Jonsson, Patrik

    2014-01-01

    The primary aim of this study was to determine whether the information collected as part of the at-sea-sampling program could be used to identify hydrographical and environmental variables that are influential on catch rates of Norway lobster. Ultimately, we wanted to know whether environmental...

  12. Comparing the catch composition, profitability and discard survival from different trammel net designs targeting common spiny lobster (Palinurus elephas in a Mediterranean fishery

    Directory of Open Access Journals (Sweden)

    Gaetano Catanese

    2018-05-01

    Full Text Available In the Balearic Islands, different trammel net designs have been adopted to promote fisheries sustainability and reduce discards. Here, we compare the catch performance of three trammel net designs targeting the spiny lobster Palinurus elephas in terms of biomass, species composition and revenue from commercial catches and discards. Designs differ in the netting fiber type (standard polyfilament, PMF, or a new polyethylene multi-monofilament, MMF and the use of a guarding net or greca, a mesh piece intended to reduce discards. Catches were surveyed by an on-board observer from 1,550 netting walls corresponding to 70 nets. The number of marketable species captured indicated that the lobster trammel net fishery has multiple targets, which contribute significantly to the total revenue. The discarded species ranged from habitat-forming species to elasmobranches, but the magnitude of gear-habitat interactions on the long term dynamics of benthos remains unclear. No relevant differences in revenue and weight of discards were detected after Bayesian analyses. However, the species composition of discards was different when using greca. Interestingly, high immediate survival was found for discarded undersized lobsters, while a seven day survival assessment, using captive observation, gave an asymptotic estimate of survival probability as 0.64 (95% CI [0.54–0.76]. Therefore, it is recommended that it would be beneficial for this stock if an exemption from the EU landing obligation regulation was sought for undersized lobsters in the Balearic trammel net fishery.

  13. Galatheoidea are not monophyletic - molecular and morphological phylogeny of the squat lobsters (Decapoda: Anomura) with recognition of a new superfamily.

    Science.gov (United States)

    Schnabel, K E; Ahyong, S T; Maas, E W

    2011-02-01

    The monophyletic status of the squat lobster superfamily Galatheoidea has come under increasing doubt by studies using evidence as diverse as larval and adult somatic morphology, sperm ultrastructure, and molecular data. Here we synthesize phylogenetic data from these diverse strands, with the addition of new molecular and morphological data to examine the phylogeny of the squat lobsters and assess the status of the Galatheoidea. A total of 64 species from 16 of the 17 currently recognised anomuran families are included. Results support previous work pointing towards polyphyly in the superfamily Galatheoidea and Paguroidea, specifically, suggesting independent origins of the Galatheidae+Porcellanidae and the Chirostylidae+Kiwaidae. Morphological characters are selected that support clades resolved in the combined analysis and the taxonomic status of Galatheoidea sensu lato is revised. Results indicate that Chirostylidae are more closely related to an assemblage including Aegloidea, Lomisoidea and Paguroidea than to the remaining Galatheoidea and are referred to the superfamily Chirostyloidea to include the Chirostylidae and Kiwaidae. A considerable amount of research highlighting morphological differences supporting this split is discussed. The Galatheoidea sensu stricto is restricted to the families Galatheidae and Porcellanidae, and diagnoses for both Chirostyloidea and Galatheoidea are provided. Present results highlight the need for a detailed revision of a number of taxa, challenge some currently used morphological synapomorphies, and emphasise the need for integrated studies with wide taxon sampling and multiple data sources to resolve complex phylogenetic questions. Copyright © 2010 Elsevier Inc. All rights reserved.

  14. Total arsenic in raw and boiled portions of Norway lobster (Nephrops norvegicus) from the central Adriatic Sea.

    Science.gov (United States)

    Visciano, Pierina; Perugini, Monia; Manera, Maurizio; Abete, Maria Cesarina; Tarasco, Renata; Salese, Carmine; Amorena, Michele

    2013-12-18

    The distribution of total arsenic in different portions of Norway lobster (Nephrops norvegicus L., Crustacea) was studied both in fresh samples and after a boiling process. All individuals (n = 80) were selected of medium standard commercial size (13-15 cm). The highest mean concentrations (26.86 ± 1.57 mg/kg wet weight (ww)) were found in the raw brown meat of the crustacean, probably due to its detoxification role, whereas the lowest mean values (15.97 ± 0.85 mg/kg ww) were in the raw exoskeleton. The raw white meat reported mean values of 16.09 ± 0.61 mg/kg ww. The levels of arsenic contamination detected in the boiled portions showed a significant (p < 0.01) decrease compared to the raw portions, as a consequence of solubilization phenomena. In fact, a large amount of arsenic from raw lobsters was transferred to the corresponding boiling broth. In the most commonly consumed portion, the white meat, only slight losses (7.22%) in total arsenic content were observed compared to the raw portion.

  15. A new species of Carcinonemertes, Carcinonemertes conanobrieni sp. nov. (Nemertea: Carcinonemertidae, an egg predator of the Caribbean spiny lobster, Panulirus argus.

    Directory of Open Access Journals (Sweden)

    Lunden Alice Simpson

    Full Text Available A new species of nemertean worm belonging to the genus Carcinonemertes is described from egg masses of the Caribbean spiny lobster Panulirus argus from the Florida Keys, Florida, USA. This is the first species of Carcinonemertes reported to infect P. argus or any other lobster species in the greater Caribbean and western Atlantic Ocean. Carcinonemertes conanobrieni sp. nov. varies in body color from a translucent white to a pale orange, with males ranging in total body length from 2.35 to 12.71 mm and females ranging from 0.292 to 16.73 mm. Among the traits that separate this new species from previously described species in the genus Carcinonemertes are a relatively wide stylet basis, minimal sexual size dimorphism, and a unique mucus sheath decorated with external hooks. Also, juvenile worms were found to encyst themselves next to lobster embryos and female worms lay both long strings of eggs wound throughout the lobster's setae as well as spherical cases that are attached to lobster embryos. The stylet length and stylet basis remain unchanged throughout ontogeny for both male and female worms. Maximum likelihood and Bayesian inference phylogenetic analyses separated this newly described species from all other species of Carcinonemertes with available COI sequences. Carcinonemertes spp. are voracious egg predators and have been tied to the collapse of various crustacean fisheries. The formal description of this new species represents the first step to understand putative impacts of this worm on the population health of one of the most lucrative yet already depressed crustacean fisheries.

  16. Report of the second joint meeting of the Working Party on Assessment of Fish Resources and the Working Party on Stock Assessment of Shrimp and Lobster Resources, Mexico City, Mexico, 26-29 November 1979

    National Research Council Canada - National Science Library

    1981-01-01

    The final formal report of the WECAFC Working Parties on Assessment of Fish Resources and on Stock Assessment of Shrimp and Lobster Resources, held in Mexico City, Mexico, 26-29 November 1979 is presented...

  17. Morphology of the male gonads of the spiny lobster Panulirus laevicauda (Latreille, 1817

    Directory of Open Access Journals (Sweden)

    Ana Valêsca Pinto de Lima

    2008-08-01

    Full Text Available The present study represented a contribution to the knowledge of the cytological and histological aspects of decapods' reproductive system, describing male germ cells of the spiny lobster Panulirus laevicauda. Seventy-one specimens of different sizes were caught off Fortaleza (Ceará, Brazil. Their testes were removed and fixed in Bouin solution, then, after 24 hours, dehydrated, cleared and embedded in the paraffin. Sections (4 µm thick were stained with hematoxylin-eosin. The testes appeared macroscopically as a pair of long and highly convoluted tubes joined by a transversal commissure giving the organ an H-like shape. Microscopically, supporting cells and germ cells (spermatogonia I and II, spermatocytes, spermatids and spermatozoa were seen in the testicular acini. Some of the acini showed signs of the spermotocytes and the spermatogonia degeneration. The spermatozoa were small cells with the peripheral nuclei and a lightly basophilic cytoplasm. They were nonmotile gametes and are characterized by the absence of a flagellum, but they had spikes radiating from the body. Three stages of follicular development in the mature individuals were observed: (a predominance of spermatogonia I and II; (b increasing numbers of spermatocytes I and II; and (c spermatocytes I and II were prevalent. All the three stages of the spermatozoa were observed in the follicular lumen. These observations agreed with the published descriptions of other palinurid and homarid lobsters. A histochemical analysis of the testes showed that the main component of the tunic was collagenous fibers, that the seminal fluid contained plenty of glycoproteins and carboxyl-glycoconjugates and that the spherical bodies and spermatozoa contained glycoproteins and mucoproteins.O presente trabalho tem como objetivo ampliar os conhecimentos na área de histologia e citologia do sistema reprodutivo dos Decapoda, descrevendo as células germinativas do macho da lagosta Panulirus

  18. Somaclonal variation in micropropagated Heliconia bihai cv. Lobster Claw I plantlets (Heliconiaceae Variação somaclonal em mudas micropropagadas de Helicônia, Heliconia Bihai cv. Lobster Claw I (Heliconiaceae

    Directory of Open Access Journals (Sweden)

    Paulo Hercílio Viegas Rodrigues

    2008-12-01

    Full Text Available The occurrence of somaclonal variation is described in various cultures of agronomic interest. Such variation can be of benefit in the development of new flower varieties. In this study, the occurrence of somaclonal variation in micropropagated changes of Heliconia bihai cv. Lobster Claw I was investigated. Stem apexes were introduced in MS culture media with the addition of 2.5 mg L-1 of benzylaminopure (BAP and 500 mg L-1 of sodium cefotaxime. After selecting the apex stem, it was sub-cultivated in MS media and supplemented with 4.0 mg L-1 of BAP to induce side buds. To conduct the trial, 2,000 plants were selected and compared with plants originated from rhizomes. To calculate the percentage of the variants, the plant stature, the form and color of leaves and pseudostem were evaluated. The plants with buds presenting the same type of variation were considered as variants. The occurrence of three types of somaclonal variants was observed: Variation of the Chlorophyll in the Leaf, Low Stature Variant and Pseudostem and Petiole Color Variant, the latter with ornamental potential. The somaclonal variation rate for Heliconia bihai cv Lobster Claw I, under the proposed conditions, was 61.40%.A ocorrência de variação somaclonal é descrita em diversas culturas de interesse agronômico. A floricultura pode beneficiar-se dessa variabilidade, com a obtenção de novas variedades. Nesse trabalho, estudou-se a ocorrência de variação somaclonal em mudas micropropagadas de Heliconia bihai cv. Lobster Claw I. Ápices caulinares foram introduzidos em meio de cultivo MS com adição de 2,5 mg L-1 de benzilaminopurina (BAP e 500 mg L-1 de cefotaxima sódica. Após a seleção do ápice caulinar, o explante foi subcultivado em meio MS suplementado com 4,0 mg L-1 de BAP para indução de brotações. Foram selecionadas, ao acaso, 2.000 mudas e comparadas com mudas originadas de rizomas, para compor o ensaio. No cálculo da porcentagem dos variantes

  19. [Variations of the nutritional condition of lobsters Panulirus argus (Decapoda: Palinuridae) in Eastern region of the Gulf of Batabanó, Cuba].

    Science.gov (United States)

    Lopeztegui Castillo, Alexander; Capetillo Piñar, Norberto; Betanzos Vega, Abel

    2012-03-01

    Nutritional condition can affect survival and growth rate of crustaceans, and this is mostly affected by habitat conditions. This study describes the space-temporary nutritional changes in this commercially important species. With this aim, the variations in the nutritional condition (K) of lobsters from four zones (1, 2, 4 and 5) in the Gulf of Batabanó, Cuba, were determined. For this, the weight/length ratio (K=Pt/Lt) was calculated using animals captured in 1981 and 2010. The nutritional condition between areas and sexes, and years and sexes, was contrasted by a bifactorial ANOVA, and the overall length and weight of lobsters were compared using a t-Test for independent samples and unifactorial ANOVA. It was found that the nutritional condition was significantly greater in males than in females. In addition, significant variations between zones were detected for both years. Nutritional condition of lobsters from Zone five was the highest for 1981, while it was Zone two for 2010. Lobsters nutritional state showed significant variations between years, being greater in 1981 (2.34 +/- 0.84g/mm) than in 2010 (1.96 +/- 0.49g/mm). The inter-zones variations as well as the inter-annual ones seem to be related to the reported variations of the bottom type and the vegetation cover. Seasonal variations in the abundance and distribution of benthic organisms, that constitute food for lobsters, could also be influencing. The differences between sexes, however, were assumed as a consequence of the methodology used and the sexual dimorphism of the species. Due to other K estimation methods, that do not include morphometric measurements, these differences were not detected. We suggested that the P. argus nutritional condition is a good estimator of the habitat condition. Besides, according to the applied K estimation methodology, it was found that different groups of lobsters that have resemblant nutritional condition, did not necessarily observe similarities in the overall

  20. Squat lobsters (Crustacea: Anomura) from Mauritanian waters (West Africa), with the description of a new species of Munidopsis.

    Science.gov (United States)

    De Matos-Pita, Susana S; Ramil, Fran

    2014-02-20

    This paper is the result of the study of a squat lobsters collection obtained along the Mauritanian coast, between 91 and 1867 m depth, during the 'MAURIT' surveys carried out in the period from 2007 to 2010. Eumunida bella de Saint Laurent & Macpherson, 1990 (Chirostyloidea) and six species of Munida and Munidopsis (Galatheoidea) are reported in the present work.A new species, Munidopsis anaramosae n. sp. collected off northwestern Banc d'Arguin at 1000-1012 m depth, is described and illustrated. The presence of an eyespine that arises distally from the middle end of the cornea, walking legs merus spinose on dorsal and ventral margins and cheliped merus ventrally unarmed distinguish it from related species. Munida chunii Balss, 1913 is redescribed here and the new records of Munida guineae Miyake & Baba, 1970, M. speciosa von Martens, 1878 and Munidopsis chunii Balss, 1913 extend their geographical distribution northwards, and in the case of the last species, increase its bathymetric range.

  1. Modeling the Dispersal of Spiny Lobster (Palinurus elephas Larvae: Implications for Future Fisheries Management and Conservation Measures

    Directory of Open Access Journals (Sweden)

    Paul Whomersley

    2018-03-01

    Full Text Available Knowledge of larval dispersal, population dynamics and connectivity in relation to the management and conservation of commercially important species is vital if existing fisheries are to remain sustainable into the future. Larval dispersal of the commercially exploited spiny lobster, Palinurus elephas, was modeled from Marine Protected Areas located in the southwest of England for a 16-month period using a General Individuals Transport Model (GITM. The model included physical particle advection based on current fields from a 3D hydrodynamics model and a larval behavior module. Our results demonstrate the overall dispersal patterns of P. elephas larvae and highlight populations capable of self-seeding and those which are seemingly reliant on larvae from more distant populations. The results indicate where further research may be required to fully understand how populations of P. elephas are maintained at regional, national and international scales while providing us with the opportunity to discuss the effectiveness of current approaches to conservation and fisheries management.

  2. Lobster (Panulirus argus captures and their relation with environmental variables obtained by orbital sensors for Cuban waters (1997-2005

    Directory of Open Access Journals (Sweden)

    Regla Duthit Somoza

    2008-09-01

    Full Text Available Chlorophyll concentrations (Chl a data obtained from the Sea Viewing Wide Field of View Sensor (SeaWIFS ocean color monthly images, Sea Surface Temperature (SST pathfinder data obtained from the Advanced Very High Resolution Radiometer (AVHRR sensors, and lobster (Panulirus argus captures at the Cuban shelf were examined in order to analyze their spatial and temporal variability. A cross-correlation analysis was made between the standardized anomalies of the environmental variables (Chl a and SST and the standardized anomalies of lobster captures for each fishery zones for the period between 1997 and 2005. For the deep waters adjacent to the fishing zones it was not observed a clear Chl a seasonality and on average the lowest values occurred south of the Island. It is with the three years lag that Chl a had the greatest numbers of significant correlation coefficients for almost all fishing zones. However, the cross-correlation coefficients with SST showed higher values with 1,5 year lag at all zones. Since the two environmental variables obtained by satellite sensors (SST and Chl a influence the lobsters mainly during the planktonic life cycle, the cross-correlation with lobster captures begin to show significant indexes with lags of 1.5 years or more.Dados de captura da lagosta Panulirus argus na plataforma cubana foram comparados com concentrações de clorofila (Chl a e valores de Temperatura de Superfície do Mar (TSM obtidos pelos sensores Sea Viewing Wide Field of view Sensor (SeaWIFS e Advanced Very High Resolution Radiometer (AVHRR, respectivamente. Uma análise de correlação cruzada foi realizada entre as anomalias padronizadas das variáveis ambientais (Chl a e TSM e as anomalias padronizadas de capturas da lagosta para cada zona de pesca no período 1997-2005. Para as águas profundas adjacentes às zonas de pesca não foi observada uma sazonalidade evidente da Chl a. De forma geral, os menores valores de Chl a ocorreram ao sul da

  3. Genetic Isolation among the Northwestern, Southwestern and Central-Eastern Indian Ocean Populations of the Pronghorn Spiny Lobster Panulirus penicillatus

    Directory of Open Access Journals (Sweden)

    Muhamad Fadry Abdullah

    2014-05-01

    Full Text Available The pronghorn spiny lobster Panulirus penicillatus is a highly valuable species which is widely distributed in Indo-West Pacific and Eastern Pacific regions. Mitochondrial DNA control region sequences (566–571 bp were determined to investigate the population genetic structure of this species in the Indian Ocean. In total, 236 adult individuals of Panulirus penicillatus were collected from five locations in the Indian Ocean region. Almost all individuals had a unique haplotype. Intrapopulation haplotype (h and nucleotide (π diversities were high for each locality, ranging from h = 0.9986–1.0000 and π = 0.031593–0.043441. We observed distinct genetic isolation of population located at the northwestern and southwestern edge of the species range. Gene flow was found within localities in the central and eastern region of the Indian Ocean, probably resulting from an extended planktonic larval stage and prevailing ocean currents.

  4. Morphometric relationships and size at sexual maturity of the deep-sea Caribbean lobster Metanephrops binghami (Decapoda: Nephropidae in the Colombian Caribbean

    Directory of Open Access Journals (Sweden)

    José

    2017-05-01

    Full Text Available This paper describes the morphometric relationships and size at sexual maturity of deep-sea Caribbean lobster. Data were obtained in the Colombian Caribbean in four trawling surveys in November and December 2009 between 200 and 550 m depth. 709 individuals with sizes between 53.65 and 191.00 mm (TL (mean 121.17 ± 27.13 mm were measured. M. binghami had a positive allometric growth. Lobsters of the family Nephropidae have a worldwide distribution and economic importance. High levels of biomass of Metanephrops binghami have been reported in the Colombian Caribbean and this species could become a potential new resource for the Western Atlantic fishery. However, prior to the development of a new fishery, more biological research is needed to understand the life cycle of this species. Aspects such as growth, spawning, recruitment, mortality, nursery areas and associated biodiversity should be carefully studied.

  5. [Influence of lunar cycle on catches of spiny lobster Panulirus argus (Decapoda: Palinuridae) in the Gulf of Batabanó, Cuba].

    Science.gov (United States)

    Lopeztegui, Alexander; Baisre, Julio A; Capetillo, Norberto

    2011-03-01

    Many biological processes such as reproductive and migratory behaviours have been associated with moon cycles. In this study, the nocturnal light levels associated with lunar cycle (INT) were correlated with daily catch rate of lobster P. argus, during seven lunar months of 2002 fishing period, to determine a possible relationship between these variables. The lobster catches were obtained from three fishing companies that develop their activities in the Gulf of Batabanó: EPICOL that fishes in Coloma area; PESCAHABANA in Batabanó area and PESCAISLA in Isla area. Daily catch per boat (CDB) was used as a measurement of daily catch variations (catch rate). The correlation was analyzed showing it in chronological graphs based on average of CDB per lunar phases, comparing lobster catch rate per lunar phases -with the Kruskal-Wallis test-. Spearman rank correlation coefficient and cross correlation techniques were also applied. Similarities between lobster catch rate and the lunar cycle were not found. Spearman rank correlation coefficient was modularly smaller than 0.1 in all cases and demonstrated quantitatively that correlation between CDB and INT does not exist. Kruskal-Wallis test detected differences only in Batabanó area but not when making the analyses for the whole Gulf of Batabanó. Finally, the cross correlations do not detected significance in any zone, as well. It is concluded that, in opposition to what other authors have reported, the catch rates of P. argus and the lunar cycle did not show significant correlation in the Gulf of Batabanó. This trend was independent of the fishing art, which varied according to the time of the year that was analyzed.

  6. The effect of irradiation dose and storage time on the ESR signal in the cuticle of different components of the exoskeleton of Norway lobster (Nephrops norvegicus)

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, E.M. (Queen' s Univ., Belfast, Northern Ireland (United Kingdom)); Stevenson, M.H. (Department of Agriculture for Northern Ireland (United Kingdom). Food and Agricultural Chemistry Research Div. Queen' s Univ., Belfast, Northern Ireland (United Kingdom)); Gray, R. (Department for Agriculture for Northern Ireland (United Kingdom). Food and Agricultural Chemistry Research Div.)

    This paper examines the potential of ESR spectroscopy too determine if Norway lobsters have been irradiated. Ninety samples, each containing 3 whole Norway lobsters, were prepared, thirty were used as controls while the remaining sixty were given irradiation doses of approximately either 1 or 3 kGy. Following irradiation the samples were stored at 1[sup o]C for 0, 7, 14, 21 or 28 d. After each storage period the cuticle of the tail, carapace, claws and walking legs was removed, freeze-dried and ground prior to analysis using ESR spectroscopy. The control spectra were subtracted from their respective irradiated spectra thereby leaving the radiation-induced signal. Peak heights of the signals were measured. The ESR signals derived from the different components of the exoskeleton were similar in shape and varied only in their intensities. The claw samples gave the most intense signal while that from the walking legs was the weakest. There was a significant decay in the signal intensity over the storage period with the signal derived from cuticle of the claws showing the greatest diminution (44%) and that of the tail the least (17%). The signal intensities of the walking legs and carapace decreased by 22% and 30% respectively. In conclusion ESR spectroscopy is a useful technique for the qualitative detection of irradiated Norway lobster and shows considerable potential for quantification of dose received. (author).

  7. Acid-base balance and changes in haemolymph properties of the South African rock lobsters, Jasus lalandii, a palinurid decapod, during chronic hypercapnia.

    Science.gov (United States)

    Knapp, Jarred L; Bridges, Christopher R; Krohn, Janina; Hoffman, Louwrens C; Auerswald, Lutz

    2015-06-05

    Few studies exist reporting on long-term exposure of crustaceans to hypercapnia. We exposed juvenile South African rock lobsters, Jasus lalandii, to hypercapnic conditions of pH 7.3 for 28 weeks and subsequently analysed changes in the extracellular fluid (haemolymph). Results revealed, for the first time, adjustments in the haemolymph of a palinurid crustacean during chronic hypercapnic exposure: 1) acid-base balance was adjusted and sustained by increased bicarbonate and 2) quantity and oxygen binding properties of haemocyanin changed. Compared with lobsters kept under normocapnic conditions (pH 8.0), during prolonged hypercapnia, juvenile lobsters increased bicarbonate buffering of haemolymph. This is necessary to provide optimum pH conditions for oxygen binding of haemocyanin and functioning of respiration in the presence of a strong Bohr Effect. Furthermore, modification of the intrinsic structure of the haemocyanin molecule, and not the presence of molecular modulators, seems to improve oxygen affinity under conditions of elevated pCO2. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. The effect of irradiation dose and storage time on the ESR signal in the cuticle of different components of the exoskeleton of Norway lobster (Nephrops norvegicus)

    International Nuclear Information System (INIS)

    Stewart, E.M.; Stevenson, M.H.; Gray, R.

    1993-01-01

    This paper examines the potential of ESR spectroscopy too determine if Norway lobsters have been irradiated. Ninety samples, each containing 3 whole Norway lobsters, were prepared, thirty were used as controls while the remaining sixty were given irradiation doses of approximately either 1 or 3 kGy. Following irradiation the samples were stored at 1 o C for 0, 7, 14, 21 or 28 d. After each storage period the cuticle of the tail, carapace, claws and walking legs was removed, freeze-dried and ground prior to analysis using ESR spectroscopy. The control spectra were subtracted from their respective irradiated spectra thereby leaving the radiation-induced signal. Peak heights of the signals were measured. The ESR signals derived from the different components of the exoskeleton were similar in shape and varied only in their intensities. The claw samples gave the most intense signal while that from the walking legs was the weakest. There was a significant decay in the signal intensity over the storage period with the signal derived from cuticle of the claws showing the greatest diminution (44%) and that of the tail the least (17%). The signal intensities of the walking legs and carapace decreased by 22% and 30% respectively. In conclusion ESR spectroscopy is a useful technique for the qualitative detection of irradiated Norway lobster and shows considerable potential for quantification of dose received. (author)

  9. Trophic preference and preliminary indication of phylloplane fungal influence on the diet of the non-native Gammarus roeselii Gervais 1835 (Amphipoda, Gammaridae in the sub-lacustrine Ticino river basin (Lombardy, Northern Italy

    Directory of Open Access Journals (Sweden)

    Daniele Paganelli

    2017-03-01

    Full Text Available Gammarids are one of the most successful invaders in freshwater ecosystems due to both their diet plasticity and high reproductive capacity. One such amphipod, Gammarus roeselii, has recently colonised the southern part of the sub-lacustrine Ticino River basin (Northern Italy, where its ecological niche overlaps with the native species Echinogammarus stammeri. In the present paper the food preferences of G. roeselii have been investigated, testing the palatability of different food sources: three macrophytes and three different leaf debris. Moreover, an explorative mycological analysis on the three different leaf debris used in the experiment has been performed. Results of the short-term experiment suggest that aquatic plants are less palatable than allocthonous detritus, probably because they can contain secondary metabolites (i.e. tannins and they have lower nutrient tissues with very high water content. On the contrary, G. roeselii showed a clear preference for the oak leaves, resulted colonized by a more abundant fungal biomass and, therefore, more palatable too.

  10. Caffeine-supplemented diet modulates oxidative stress markers and improves locomotor behavior in the lobster cockroach Nauphoeta cinerea.

    Science.gov (United States)

    da Silva, Cícera Simoni; de Cássia Gonçalves de Lima, Rita; Elekofehinti, Olusola Olalekan; Ogunbolude, Yetunde; Duarte, Antonia Eliene; Rocha, João Batista Teixeira; Alencar de Menezes, Irwin Rose; Barros, Luiz Marivando; Tsopmo, Appolinaire; Lukong, Kiven Erique; Kamdem, Jean Paul

    2018-02-25

    The effects of caffeine supplementation is well documented in conventional animal models, however, in the lobster cockroaches Nauphoeta cinerea, they have not been reported. Thus, the aim of this study was to investigate the locomotor behavior and biochemical endpoints in the head of the nymphs of N. cinerea following 60 days exposure to food supplemented with 0, 0.5, 1.0, 2.5, 5.0 and 10.0 mg of caffeine/g of diet. The analysis of the locomotor behavior using the video-tracking software, Any-maze, for 12 min revealed that caffeine supplementation caused significant behavioral improvement. There was increase in distance travelled, velocity, frequency of rotation and turn angle (stereotypical behavior such as circling movements), and this was supported by the representative track plots of the path travelled by cockroaches in the open-field arena. In addition, caffeine supplementation markedly increased total thiol and non-protein thiol glutathione (GSH) levels in the heads of cockroaches, and this was in parallel with significant reduction of lipid peroxidation and free Fe(II) content. Taking together, our results indicate that long-term caffeine supplementation may exert preventive effects against oxidative stress and support the use of N. cinerea as an efficient alternative model to assess the efficacy of food molecules. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Mechanisms underlying odorant-induced and spontaneous calcium signals in olfactory receptor neurons of spiny lobsters, Panulirus argus.

    Science.gov (United States)

    Tadesse, Tizeta; Derby, Charles D; Schmidt, Manfred

    2014-01-01

    We determined if a newly developed antennule slice preparation allows studying chemosensory properties of spiny lobster olfactory receptor neurons under in situ conditions with Ca(2+) imaging. We show that chemical stimuli reach the dendrites of olfactory receptor neurons but not their somata, and that odorant-induced Ca(2+) signals in the somata are sufficiently stable over time to allow stimulation with a substantial number of odorants. Pharmacological manipulations served to elucidate the source of odorant-induced Ca(2+) transients and spontaneous Ca(2+) oscillations in the somata of olfactory receptor neurons. Both Ca(2+) signals are primarily mediated by an influx of extracellular Ca(2+) through voltage-activated Ca(2+) channels that can be blocked by CoCl2 and the L-type Ca(2+) channel blocker verapamil. Intracellular Ca(2+) stores contribute little to odorant-induced Ca(2+) transients and spontaneous Ca(2+) oscillations. The odorant-induced Ca(2+) transients as well as the spontaneous Ca(2+) oscillations depend on action potentials mediated by Na(+) channels that are largely TTX-insensitive but blocked by the local anesthetics tetracaine and lidocaine. Collectively, these results corroborate the conclusion that odorant-induced Ca(2+) transients and spontaneous Ca(2+) oscillations in the somata of olfactory receptor neurons closely reflect action potential activity associated with odorant-induced phasic-tonic responses and spontaneous bursting, respectively. Therefore, both types of Ca(2+) signals represent experimentally accessible proxies of spiking.

  12. Acidity enhances the effectiveness of active chemical defensive secretions of sea hares, Aplysia californica, against spiny lobsters, Panulirus interruptus.

    Science.gov (United States)

    Shabani, Shkelzen; Yaldiz, Seymanur; Vu, Luan; Derby, Charles D

    2007-12-01

    Sea hares such as Aplysia californica, gastropod molluscs lacking a protective shell, can release a purple cloud of chemicals when vigorously attacked by predators. This active chemical defense is composed of two glandular secretions, ink and opaline, both of which contain an array of compounds. This secretion defends sea hares against predators such as California spiny lobsters Panulirus interruptus via multiple mechanisms, one of which is phagomimicry, in which secretions containing feeding chemicals attract and distract predators toward the secretion and away from the sea hare. We show here that ink and opaline are highly acidic, both having a pH of approximately 5. We examined if the acidity of ink and opaline affects their phagomimetic properties. We tested behavioral and electrophysiological responses of chemoreceptor neurons in the olfactory and gustatory organs of P. interruptus, to ink and opaline of A. californica within their natural range of pH values, from approximately 5 to 8. Both behavioral and electrophysiological responses to ink and opaline were enhanced at low pH, and low pH alone accounted for most of this effect. Our data suggest that acidity enhances the phagomimetic chemical defense of sea hares.

  13. Towards a Supertree of Arthropoda: A Species-Level Supertree of the Spiny, Slipper and Coral Lobsters (Decapoda: Achelata).

    Science.gov (United States)

    Davis, Katie E; Hesketh, Thomas W; Delmer, Cyrille; Wills, Matthew A

    2015-01-01

    While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs), invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters) as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK) and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy.

  14. Investigation of genetic structure between deep and shallow populations of the southern Rock Lobster, Jasus edwardsii in Tasmania, Australia.

    Directory of Open Access Journals (Sweden)

    Erin M J Morgan

    Full Text Available The southern rock lobster, Jasus edwardsii, shows clear phenotypic differences between shallow water (red coloured and deeper water (pale coloured individuals. Translocations of individuals from deeper water to shallower waters are currently being trialled as a management strategy to facilitate a phenotypic change from lower value pale colouration, common in deeper waters, to the higher value red colouration found in shallow waters. Although panmixia across the J. edwardsii range has been long assumed, it is critical to assess the genetic variability of the species to ensure that the level of population connectivity is appropriately understood and translocations do not have unintended consequences. Eight microsatellite loci were used to investigate genetic differentiation between six sites (three shallow, three deep across southern Tasmania, Australia, and one from New Zealand. Based on analyses the assumption of panmixia was rejected, revealing small levels of genetic differentiation across southern Tasmania, significant levels of differentiation between Tasmania and New Zealand, and high levels of asymmetric gene flow in an easterly direction from Tasmania into New Zealand. These results suggest that translocation among Tasmanian populations are not likely to be problematic, however, a re-consideration of panmictic stock structure for this species is necessary.

  15. Spatial variation in size at onset of maturity of female southern rock lobster Jasus edwardsii around Tasmania, Australia

    Directory of Open Access Journals (Sweden)

    Caleb Gardner

    2006-09-01

    Full Text Available P align=justify>The size at onset of maturity (SOM of female Jasus edwardsii (Hutton, 1875 was estimated at 50 sites around Tasmania, Australia, based on the presence of ovigerous setae. There was a distinct spatial cline with the largest SOM being found at northwestern sites and the smallest at southwestern sites. Variation in SOM between sites was substantial and ranged from 59 mm to 112 mm carapace length. The observed decline in SOM from north to south was the reverse of that described for the same species at similar latitudes in New Zealand, which suggests that SOM in J. edwardsii is regulated by factors in addition to temperature. The effect of density on female SOM was investigated by comparing SOM estimates from two marine reserves with adjacent fished sites; however, there was no evidence of a decline in SOM with increasing density as predicted. A model of SOM predicted by latitude and longitude is described to facilitate spatial modelling of lobster stocks. The substantial and predictable spatial variation in SOM implies that management of this fishery would be improved by incorporating spatial elements, such as regional legal minimum size limits.

  16. ECOBIOLOGICAL STUDY ON BURROWING MUD LOBSTER THALASSINA ANOMALA (HERBST, 1804 (DECAPODA : THALASSINIDEA IN THE INTERTIDAL MANGROVE MUDFLAT OF DELTAIC SUNDARBANS

    Directory of Open Access Journals (Sweden)

    S. K. Dubey

    2012-07-01

    Full Text Available Populations of mud lobster Thalassina anomala were studied on tidal flats in the Sagar island of Indian Sundarbans. Ecologically they are recognized as the 'friends of mangrove' and a 'Biological Marvel' of the system. They turn up the deep soil to the surface by regular night shift burrowing exercise and help to import aerated tidal water in the burrows 2 to 2.5 meter deep. They have extra ordinary morphological adaptation and structural changes and completely resort to detritivore diet. Being thigmotactic it seldom exposes to atmospheric oxygen and forms its palace underground with a central chamber having 5 to 6 radiated tunnels opening to the surface covered with earth mounds. It displays its engineering skill of bioturbation in tunneling. During tunneling the shrimp feeds on the mud packed with detritus and derived its required micronutrients. Being mud dwelling and mud eating habits, it's respiratory and food manipulating apparatus underwent transformations which demands intensive investigation. Thalassinid burrow associates comprising mieo and microorganisms also provide good subject of study of species specific interaction, exchanging of materials between associate partners.

  17. Luminous vibriosis in rock lobster Jasus verreauxi (Decapoda: Palinuridae) phyllosoma larvae associated with infection by Vibrio harveyi.

    Science.gov (United States)

    Diggles, B K; Moss, G A; Carson, J; Anderson, C D

    2000-11-14

    Studies were conducted to determine the cause of outbreaks of luminous vibriosis in phyllosoma larvae of the packhorse rock lobster Jasus verreauxi reared in an experimental culture facility. On 2 separate occasions mortalities of up to 75% over a period of 4 wk were observed in 4th to 5th and 8th to 10th instar phyllosomas at water temperatures of 20 and 23 degrees C, respectively. Affected larvae became opaque, exhibited small red spots throughout the body and pereiopods, and were faintly luminous when viewed in the dark. Histopathology showed that the gut and hepatopancreas tubules of moribund phyllosomas contained massive bacterial plaques. The hepatopancreas tubules of moribund larvae were atrophic and some contained necrotic cells sloughed into the lumen. Dense, pure cultures of a bacterium identified as Vibrio harveyi were isolated from moribund larvae. The disease syndrome was reproduced by in vivo challenge and V. harveyi was successfully reisolated from diseased larvae after apparently healthy larvae were exposed by immersion to baths of more than 10(4) V. harveyi ml(-1) at 24 degrees C. Injured larvae were more susceptible to infection than were healthy larvae. Survival of larvae experimentally and naturally exposed to V. harveyi was improved when antibiotics were administered via bath exposures.

  18. Towards a Supertree of Arthropoda: A Species-Level Supertree of the Spiny, Slipper and Coral Lobsters (Decapoda: Achelata.

    Directory of Open Access Journals (Sweden)

    Katie E Davis

    Full Text Available While supertrees have been built for many vertebrate groups (notably birds, mammals and dinosaurs, invertebrates have attracted relatively little attention. The paucity of supertrees of arthropods is particularly surprising given their economic and ecological importance, as well as their overwhelming contribution to biodiversity. The absence of comprehensive archives of machine-readable source trees, coupled with the need for software implementing repeatable protocols for managing them, has undoubtedly impeded progress. Here we present a supertree of Achelata (spiny, slipper and coral lobsters as a proof of concept, constructed using new supertree specific software (the Supertree Toolkit; STK and following a published protocol. We also introduce a new resource for archiving and managing published source trees. Our supertree of Achelata is synthesised from morphological and molecular source trees, and represents the most complete species-level tree of the group to date. Our findings are consistent with recent taxonomic treatments, confirming the validity of just two families: Palinuridae and Scyllaridae; Synaxidae were resolved within Palinuridae. Monophyletic Silentes and Stridentes lineages are recovered within Palinuridae, and all sub-families within Scyllaridae are found to be monophyletic with the exception of Ibacinae. We demonstrate the feasibility of building larger supertrees of arthropods, with the ultimate objective of building a complete species-level phylogeny for the entire phylum using a divide and conquer strategy.

  19. The use of at‐sea‐sampling data to dissociate environmental variability in Norway lobster (Nephrops norvegicus) catches to improve resource exploitation efficiency within the Skagerrak/Kattegat trawl fishery

    DEFF Research Database (Denmark)

    Feekings, Jordan P.; Christensen, Asbjørn; Jonsson, Patrik

    2015-01-01

    Research into the influence of environmental variables on the behaviour of Norway lobster (Nephrops norvegicus), and hence catch rates, dates back to the 1960s (e.g., Höglund and Dybern, Diurnal and seasonal variations in the catch‐composition of Nephrops norvegicus (L.) at the Swedish west coast...... on commercial trawl catches of Nephrops norvegicus (L.). ICES J. Mar. Sci. 58:1318). Here, we aimed to dissociate environmental variability in Norway lobster catches to improve resource exploitation efficiency within the Skagerrak and Kattegat trawl fisheries by utilising data collected as part of an extensive...

  20. Invertebrate predation on egg masses of the European cuttlefish, Sepia officinalis: An experimental approach

    Science.gov (United States)

    Martins, Catarina P. P.; Fernández-Álvarez, Fernando Á.; Villanueva, Roger

    2018-01-01

    The eggs of the European cuttlefish, Sepia officinalis, develop attached to the seafloor in shallow water habitats and possess a relatively thick black capsule that protects them from the surrounding environment. Since embryological development may take several months, eggs are vulnerable to a variety of threats present in shallow waters, including predation. This study investigates predation of S. officinalis eggs by benthic invertebrates. Twenty-eight invertebrate species from 6 different phyla and with diverse feeding habits were tested as potential predators under laboratory conditions. We also investigated how the feeding traits of these species are related to the mechanical ability to break the egg capsule and prey upon cuttlefish embryos. Species that fed on cuttlefish eggs were the sea snail Bolinus brandaris, the crab Cancer pagurus, the hermit crab Dardanus arrosor, the lobster Homarus gammarus, the invasive blue crab Callinectes sapidus, the shrimp Squilla mantis, the sea urchins Echinus melo, Cidaris sp. and Paracentrotus lividus and the starfish Astropecten aranciacus. It is of note that C. sapidus is a potential predatory crab, which raises the concern that this invasive species may constitute a novel threat for cuttlefish eggs as more populations become established in NE Atlantic waters. Of the biological traits examined, prey capture tools in the tested species best explained the experimental feeding results, suggesting that predation of S. officinalis eggs was determined generally by a mechanical factor and highlighting the importance of the protective egg capsule against predators. However, chemosensory factors are likely to be implicated as well. Thus, this work contributes to the understanding of the ecology of early life stages of cuttlefish and the factors that can affect offspring survival and subsequently impact the recruitment of this species.

  1. Significant Enrichment of Polyunsaturated Fatty Acids (PUFAs) in the Lipids Extracted by Supercritical CO2 from the Livers of Australian Rock Lobsters (Jasus edwardsii).

    Science.gov (United States)

    Nguyen, Trung T; Zhang, Wei; Barber, Andrew R; Su, Peng; He, Shan

    2015-05-13

    Australian rock lobster (Jasus edwardsii) liver contains approximately 24.3% (w/w) lipids, which can contain a high amount of polyunsaturated fatty acids (PUFAs). However, this material has been found to be contaminated with arsenic (240 mg/kg) and cadmium (8 mg/kg). The high level of contaminants in the raw material and the large amount of PUFAs in the lipids prove a significant challenge in the extraction of high-quality lipids from this byproduct by conventional methods. Supercritical carbon dioxide (SC-CO2) extraction is a highly promising technology for lipid extraction with advantages including low contamination and low oxidation. The technique was optimized to achieve nearly 94% extraction of lipids relative to conventional Soxhlet extraction in Australian rock lobster liver at conditions of 35 MPa and 50 °C for 4 h. The extracted lipids are significantly enriched in PUFAs at 31.3% of total lipids, 4 times higher than those in the lipids recovered by Soxhlet extraction (7.8%). Specifically, the concentrations of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in SC-CO2 extraction are 7 times higher than those obtained by Soxhlet extraction. Moreover, very small amounts of toxic heavy metals such as lead (Pb), arsenic (As), mercury (Hg), and cadmium (Cd) were detected in the SC-CO2-extracted lipids, 0.5-27 times lower than those in the Soxhlet-extracted lipids, which are 40-200 times lower than the regulatory limit maximum values. The low levels of contaminants and the high proportion of PUFAs (dominated by DHA and EPA) found in the SC-CO2-extracted lipids from Australian rock lobster liver suggest that the material could potentially be used as a valuable source of essential fatty acids for human consumption.

  2. Distribution and function of splash, an achaete-scute homolog in the adult olfactory organ of the Caribbean spiny lobster Panulirus argus

    Science.gov (United States)

    Tadesse, Tizeta; Schmidt, Manfred; Walthall, William W.; Tai, Phang C.; Derby, Charles D.

    2011-01-01

    achaete-scute complex (ASC) genes, which encode basic helix-loop-helix transcription factors, regulate embryonic and adult neurogenesis in many animals. In adult arthropods, including crustaceans, ASC homologs have been identified but rarely functionally characterized. We took advantage of the recently identified crustacean homolog, splash (spiny lobster achaete scute homolog), in the olfactory organ of the Caribbean spiny lobster Panulirus argus to examine its role in adult neurogenesis. We tested the hypothesis that splash is associated with but not restricted to sensory neuron formation in the olfactory organ, the antennular lateral flagellum (LF), of adult spiny lobsters. We demonstrated splash labeling in epithelial cells across LF developmental zones (i.e., proliferation and mature zones), in auxiliary cells surrounding dendrites of olfactory receptor neurons (ORNs), and in immature and mature ORNs, but not in granulocytes or chromatophores. Since ORN proliferation varies with molt stage, we examined splash expression across molt stages and found that molt stage affected splash expression in the ORN mature zone but not in the proliferation zone. In vivo incorporation of bromodeoxyuridine (BrdU) showed no correlation in the cellular pattern of splash expression and BrdU labeling. The intensity of splash labeling was dramatically enhanced in the proliferation zones following LF damage, suggesting enhanced splash expression during repair and/or regeneration. We conclude that splash is not closely associated with the formation of sensory neurons under normal physiological conditions, and we propose that splash is involved in repair and regeneration. We also propose that splash has additional roles other than neurogenesis in adult crustaceans. PMID:21394934

  3. Enhancement of juvenile Caribbean spiny lobsters: an evaluation of changes in multiple response variables with the addition of large artificial shelters.

    Science.gov (United States)

    Briones-Fourzán, Patricia; Lozano-Alvarez, Enrique; Negrete-Soto, Fernando; Barradas-Ortiz, Cecilia

    2007-03-01

    Shortage of natural crevice shelters may produce population bottlenecks in juvenile Caribbean spiny lobsters (Panulirus argus), a socially gregarious species. We conducted a field experiment to test enhancement of a local population of juvenile P. argus with the addition of artificial shelters ("casitas") that mimic large crevices (1.1 m(2) in surface area and 3.8 cm in height). Changes in density and biomass of juvenile lobsters 15-50 mm carapace length (CL) were assessed with a multiple before-after control-impact (MBACI) analysis. Separate analyses were also conducted on small (15-35 mm CL) and large (35.1-50 mm CL) juveniles to assess size-related effects. First, we carried out 13 lobster surveys on nine fixed 1-ha sites over a shallow reef lagoon ("before" period). Then, we deployed ten casitas in each of five sites and left four sites as controls, and conducted 22 further surveys ("after" period). Deployment of casitas resulted in a sixfold increase in juvenile density (76% contributed by small and 24% by large juveniles) and a sevenfold increase in biomass (40 and 60%, respectively). Capture-recapture results revealed that enhancement was achieved not by promoting individual growth but by increasing survival, persistence, and foraging ranges of small and large juveniles. Casitas both mitigated shortage of natural shelter and increased sociality, allowing for cohabitation of smaller, more vulnerable juveniles with larger conspecifics that have greater defensive abilities. Casitas may help enhance local populations of juvenile P. argus in Caribbean seagrass habitats, typically poor in natural crevice shelters. The use of MBACI and the simultaneous assessment of multiple interrelated response variables may be a powerful analytical approach to test shelter limitation in other species and to examine the function of structural habitat in other systems.

  4. Propagación in vitro de Heliconia bihai (L. cv. Lobster Salmón a partir de meristemos florales In vitro propagation of Heliconia bihai (L. cv. Lobster Salmón from flowering buds

    Directory of Open Access Journals (Sweden)

    Marta Leonor Marulanda-ángel

    2011-04-01

    Full Text Available Se desarrolló un protocolo de propagación in vitro a partir de meristemos florales para Heliconia bihai cv. Lobster Salmón. Para el efecto se establecieron 250 yemas florales en diferentes tiempos utilizando NaClO al 1% durante 20 min. El medio de establecimiento Murashige y Skoog con mejores resultados fue BAP (2 mg/lt, AIA (1 mg/lt y 0.1 g/lt de L-cisteína. La mayor produccion de brotes en multiplicación se obtuvo con 6 mg/lt de BAP y con un subcultivo posterior en medio con 2 mg/lt de BAP y 0.5 mg/lt de AIA, alcanzando una tasa de multiplicación de tres nuevas yemas. El enraizamiento de las plántulas in vitro se logró con 1.3 mg/lt de AIA. La aclimatación en vivero fue 92% de supervivencia. Se realizó un análisis de varianza (Anova y un test de Tukey para las variables evaluadas las cuales mostraron diferencias estadísticas en cada fase. La propagación in vitro de heliconias a partir de yemas florales requiere mayor tiempo en la fase de establecimiento y multiplicación, no obstante permite mayores porcentajes de supervivencia y una menor contaminación, ofreciendo material de siembra de diferentes especies de esta planta de interés comercial.A protocol for in vitro propagation of Heliconia bihai cv. Lobster Salmón was developed using flowering buds as initial explants. 250 flowering buds were established in different assays with NaClO at 1% during 20 minutes. The establishment in Murashige & Skoog's medium with BAP (2mg/L, AIA (1 mg/L and L-cystein (0.1 g/L showed the best results. Shoot multiplication was obtained with BAP (6 mg/L with a subsequent subculture in a medium with BAP (2 mg/L and AIA (0.5 mg/L, reaching multiplication rates of 3.0 new shoots. Rooting was achieved with AIA 1.3 mg/L. The survival rate during greenhouse acclimatization was 92%. Analysis of variance (ANOVA and Turkey's test were realized for each of the variables evaluated that showed statistical differences in all stages. The in vitro propagation of

  5. From Fishing to Fish Processing: Separation of Fish from Crustaceans in the Norway Lobster-Directed Multispecies Trawl Fishery Improves Seafood Quality.

    Directory of Open Access Journals (Sweden)

    Junita D Karlsen

    Full Text Available Fishing gears have negative impacts on seafood quality, especially on fish in the mixed trawl fishery targeting Norway lobster (Nephrops norvegicus. In this fishery, which is worth about €80 millions in Denmark alone, the quality of fish can be significantly improved by simple gear changes. A trawl codend divided into an upper and lower codend was designed to separate fish from Norway lobster during the fishing process by encourage fish to swim into the upper codend by using a frame at the entrance of the lower codend. Separate codends for fish and Norway lobster in the same gear provide the opportunity to selectively reduce small low-value fish, which will reduce catch weight and sorting time onboard the vessel. For this horizontally divided test codend and a standard codend, in which the catch was mixed, quality assessments were performed on the same batches of fish during three steps of the value chain: i aboard the fishing vessel; ii at the Fishermen's Collection Central, and iii in the production plant. Four species of fish and fillets from fish caught in the upper codend of the test codend were of significantly better quality for several of the assessed parameters compared with those caught in the standard codend: i newly caught fish showed significantly less scale loss and discolourations and had significantly better texture; ii landed fish had significantly better skin appearance and texture and significantly fewer discolourations; and iii fillets showed significantly fewer blood spots and had significantly better texture. There were no differences in injuries for newly caught fish or gaping and bruises for fillets between the test and standard codends. The decrease in catch-related damages in the test codend is explained by little contact between fish and animals with hard or spiny surfaces due to successful separation of fish and Norway lobster into the upper and lower codends, respectively, and by lower catch weight in the upper

  6. The effect of processing treatments on the radiation-induced ESR signal in the cuticle of irradiated Norway lobster (Nephrops norvegicus)

    International Nuclear Information System (INIS)

    Stewart, E.M.; Stevenson, M.H.; Gray, R.; McMurray, C.H.

    1993-01-01

    Cooked, frozen or chilled whole tails of Norway lobster were either not irradiated or given doses of 1, 2, 3, 4 or 5 kGy using cobalt 60 source. The cuticle was removed, freeze-dried and ground before determination of the free radical concentration using electron spin resonance (ESR) spectroscopy. The ESR signal strength increased linearly with increasing irradiation dose. In comparison to the chilled samples, cooking before irradiation significantly increased (69%) signal intensity whereas cooking after irradiation decreased (27%) signal strength. Irradiating the samples in the frozen state did not significantly alter the free radical concentration in the cuticle. (author)

  7. Miocene squat lobsters (Decapoda, Anomura, Galatheoidea) of the Central Paratethys – a review, with description of a new species of Munidopsis

    Science.gov (United States)

    Hyžný, M.; Gašparič, R.; Robins, C.M.; Schlögl, J.

    2015-01-01

    All squat lobsters of the families Galatheidae, Munididae and Munidopsidae from the Miocene of the Central Paratethys are reviewed taxonomically. Based on additional observations emended diagnoses are provided for Agononida cerovensis and Galathea weinfurteri, from the Lower and Middle Miocene, respectively. Munidopsis is represented by two species in the study area; additional data for M. lieskovensis from the Lower Miocene of Slovakia are presented and a new species, M. palmuelleri, from the Middle Miocene of Slovenia is erected. Implications for palaeoenvironmental reconstructions are briefly discussed for each taxon. PMID:26005283

  8. Three-dimensional reconstruction of the musculature of various life cycle stages of the cycliophoran Symbion americanus

    DEFF Research Database (Denmark)

    Cardoso Neves, Ricardo; Kristensen, Reinhardt Møbjerg; Wanninger, Andreas Wilhelm Georg

    2009-01-01

    Cycliophora is a very recently described phylum of acoelomate metazoans with a complex life cycle and a phylogenetic position that has been under debate ever since its discovery in 1995. Symbion americanus, which lives attached to the mouthparts of the American lobster, Homarus americanus...

  9. Differences in life-history and ecological traits between co-occurring Panulirus spiny lobsters (Decapoda, Palinuridae).

    Science.gov (United States)

    Briones-Fourzán, Patricia

    2014-01-01

    Coexistence of closely related species may be promoted by niche differentiation or result from interspecific trade-offs in life history and ecological traits that influence relative fitness differences and contribute to competitive inequalities. Although insufficient to prove coexistence, trait comparisons provide a first step to identify functional differences between co-occurring congeneric species in relation to mechanisms of coexistence. Here, a comparative review on life history and ecological traits is presented for two pairs of co-occurring species of spiny lobsters in the genus Panulirus: Panulirusgracilis and Panulirusinflatus from the Eastern Central Pacific region, and Panulirusargus and Panulirusguttatus from the Caribbean region. Panulirusgracilis and Panulirusinflatus have similar larval, postlarval, and adult sizes and a similar diet, but differ in degree of habitat specialization, fecundity, and growth rate. However, little is known on behavioral traits of these two species that may influence their competitive abilities and susceptibility to predators. The more abundant information on Panulirusargus and Panulirusguttatus shows that these two species differ more broadly in degree of habitat specialization, larval, postlarval and adult sizes, diet, fecundity, growth rate, degree of sociality, defense mechanisms, susceptibility to predators, and chemical ecology, suggesting a greater degree of niche differentiation between Panulirusargus and Panulirusguttatus than between Panulirusgracilis and Panulirusinflatus. Whether the substantial niche differentiation and apparent interspecific trade-offs between Panulirusargus and Panulirusguttatus relative to Panulirusgracilis and Panulirusinflatus reflect an earlier divergence of the former pair of species in the evolution of the genus constitutes an intriguing hypothesis. However, whether or not post-divergence evolution of each species pair occurred in sympatry remains uncertain.

  10. Natural diet of the spiny lobster, Panulirus echinatus Smith, 1869 (Crustacea: Decapoda: Palinuridae, from São Pedro and São Paulo Archipelago, Brazil

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    CA. Góes

    Full Text Available The natural diet of the spiny lobster (Panulirus echinatus from the São Pedro and São Paulo Archipelago was determined by stomach contents analysis of sixty-eight adult lobsters collected during October 2002, March, July and August 2003. Food items were grouped by gross taxa representing 11 food categories. Analysis included a qualitative (Frequency of Occurrence of item i - FOi and a quantitative method (Volume of item i - Vi. A Feed Index (FI = FOi x Vi / 100 proposed by Lauzanne (1975 was also used to indicate the importance of each food category (>50: dominant, 25-50: essential, 10-25: unimportant, <10: secondary. The most important food category determined by % FOi and % Vi, was fish, followed by crustaceans, green algae, calcareous algae, and rocks. The remaining food categories contributed to less than 30% of FOi and 10% of Vi. Although the Feed Index revealed no dominant food category in the diet of P. echinatus, fish was considered essential, crustaceans unimportant, and the remaining food categories were classified as secondary. According to the analysis, P. echinatus can be properly classified as an omnivorous and a generalist species, because it consumes a great diversity of organisms in several trophic levels. This species presents an opportunistic behaviour, feeding on the prey available at substratum. Future studies should address variations in natural diet related to sex, reproductive cycle, and seasonality.

  11. Polycyclic aromatic hydrocarbons in commercial fish and lobsters from the coastal waters of Madagascar following an oil spill in August 2009.

    Science.gov (United States)

    Rumney, Heather S; Laruelle, Franck; Potter, Kerry; Mellor, Philip K; Law, Robin J

    2011-12-01

    Concentrations of polycyclic aromatic hydrocarbons were determined in species of commercial fish and lobsters following an oil-spill just off the protected Madagascan coastline. Samples were collected along the coastline within and outside the affected area. Summed PAH concentrations ranged from 1.9 μg kg(-1) to 63 μg kg(-1) wet weight, but with no higher molecular weight PAHs (>202 Da) being detected. All concentrations of benzo[a]pyrene, benz[a]anthracene and dibenz[a,h]anthracene were 80% arising from oil sources. Profile studies indicate a low-level multisource petrogenic contamination probably representing a pre-spill background for the area. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  12. Weak feedbacks, governance mismatches, and the robustness of social-ecological systems: an analysis of the Southwest Nova Scotia lobster fishery with comparison to Maine

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    Allain J. . Barnett

    2014-12-01

    Full Text Available The insights in Governing the Commons have provided foundational ideas for commons research in the past 23 years. However, the cases that Elinor Ostrom analyzed have been exposed to new social, economic, and ecological disturbances. What has happened to these cases since the 1980s? We reevaluated one of Ostrom's case studies, the lobster and groundfishery of Port Lameron, Southwest Nova Scotia (SWNS. Ostrom suggested that the self-governance of this fishery was fragile because the government did not recognize the rights of resource users to organize their own rules. In the Maine lobster fishery, however, the government formalized customary rules and decentralized power to fishing ports. We applied the concepts of feedback, governance mismatches, and the robustness of social-ecological systems to understand the pathway of institutional change in Port Lameron. We revisited the case of Port Lameron using marine harvesters' accounts collected from participant observation, informal interviews and surveys, and literature on fisheries policy and ecology in SWNS and Maine. We found that the government's failure to recognize the customary rights of harvesters to organize has weakened feedback between the operational level, where resource users interact with the resource, and the collective-choice level, where agents develop rules to influence the behavior of resource users. This has precipitated governance mismatches, which have led harvesters to believe that the decision-making process is detrimental to their livelihoods. Thus, harvesters rarely participate in decision making and resist regulatory change. In Maine, harvesters can influence decisions through participation, but there is a trade-off. With higher influence in decisions, captains have co-opted the decision-making process. Nevertheless, we suggest that the fisheries of SWNS are more vulnerable to social-ecological change because of weaker feedbacks than in Maine. Finally, we have discussed

  13. [Reproductive pattern and mean size of sexual maturity of female lobsters Panulirus gracilis (Decapoda: Palinuridae) in Playa Lagarto, Guanacaste, Costa Rica].

    Science.gov (United States)

    Naranjo Madrigal, Helven

    2012-12-01

    The lobster P. gracilis is important as a fishery resource and also contributes to food security of fishers in coastal communities in the North Pacific of Costa Rica. Due to the importance of updating knowledge related to the reproductive pattern of this species, we analyzed 357 specimens of female lobsters caught by the fishing methods of "hookah" and lung diving, from November 2007 to October 2008 in Playa Lagarto. Furthermore, we examined the size composition by depth; monthly pattern of reproductive activity (RAI) associated with the relative increase in sea surface temperature, and also the mean size at maturity using Generalized Linear Models. Four physiological states of sexual maturity showed that females with no signs of mating or sexual maturity have a minimum mean size of 62.3mm of cephalothorax length (CL). There are characteristics of functional maturity from very small sizes ranging from 30 to 50mm CL, being the smallest berried female reported for this specie of 35.8mm CL and the highest percentage of mature females between 70 and 80mm CL. Percentages of RAI remained above 50% during the year except October and January. In addition, it observed an increase in the RAI that started from April and continued until August associated with a relative increase in temperature on March, although the correlation was not significant (r2=0.49, p>0.05). It is possible that the low mean size at maturity (70.2mm LC) for P. gracilis in this region is related to the fishing activity. It recommends the establishment of a ban in the region of at least five months (April-August) in order to protect the reproductive seasonality of the species and to promote a recruitment increase in the fishing areas.

  14. Factors affecting growth of the spiny lobsters Panulirus gracilis and Panulirus inflatus (Decapoda: Palinuridae in Guerrero, México

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    Patricia Briones-Fourzán

    2003-03-01

    Full Text Available The effects of sex, injuries, season and site on the growth of the spiny lobsters Panulirus gracilis, and P. inflatus, were studied through mark-recapture techniques in two sites with different ecological characteristics on the coast of Guerrero, México. Panulirus gracilis occurred in both sites, whereas P. inflatus occurred only in one site. All recaptured individuals were adults. Both species had similar intermolt periods, but P. gracilis had significantly higher growth rates (mm carapace length week -1 than P. inflatus as a result of a larger molt increment. Growth rates of males were higher than those of females in both species owing to larger molt increments and shorter intermolt periods in males. Injuries had no effect on growth rates in either species. Individuals of P. gracilis grew faster in site 1 than in site 2. Therefore, the effect of season on growth of P. gracilis was analyzed separately in each site. In site 2, growth rates of P. gracilis were similar in summer and in winter, whereas insite 1 both species had higher growth rates in winter than in summer. This could be due to spatial differences in processes related to changes in population density and food resources, which were documented in previous works. The overall results show that P. gracilis grows faster than P. inflatus, and that growth rates of both species are highly variable and are affected by environmental factors such as site and season, which should be taken into account when attempting to produce population growth curves for each species.Se analizaron, por medio de marcado-recaptura, los efectos del sexo, heridas, estación del año y localidad sobre el crecimiento de las langostas espinosas Panulirus gracilis Streets, 1871, y Panulirus inflatus (Bouvier, 1895 en dos localidades con diferentes características ecológicas en la costa de Guerrero, México. Panulirus gracilis se presentó en ambas localidades, mientras que P. inflatus sólo se encontró en una de

  15. Application of remote sensing to the study of the pelagic spiny lobster larval transport in the Tropical Atlantic

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    Camila Aguirre Góes Rudorff

    2009-03-01

    Full Text Available The connectivity of marine populations via larval dispersal is crucial for the maintenance of fisheries production and biodiversity. Because larval dispersion takes place on different spatial scales, global operational satellite data can be successfully used to investigate the connectivity of marine populations on different spatial and temporal scales. In fact, satellite data have long been used for the study of the large and mesoscale biological processes associated with ocean dynamics. This paper presents simulations of spiny lobster larvae transport in the Tropical Atlantic using the geostrophic currents, generated by altimetry that feeds an advection/diffusion model. Simulations were conducted over the Tropical Atlantic (20ºN to 15ºS, considering four larvae release areas: the Cape Verde Archipelago, the Ivory Coast, Ascension Island and Fernando de Noronha Archipelago. We used mean geostrophic current (MGC calculated from 2001 to 2005 to represent the mean circulation of the Tropical Atlantic. We also ran the model for the El Niño geostrophic current regime (ENGC using part of the MGC data, representing the El Niño 2002/2003 event. Results suggest that the intensification of the mesoscale ocean processes associated with El Niño events promotes the connectivity between populations, increasing the chances of a genetic flux among different stocks. We concluded that the altimetry geostrophic current data together with a relatively simple advection/diffusion model can provide useful information about the physical dynamics necessary to conduct studies on larval dispersion.A conectividade de populações marinhas através da dispersão larval é crucial para a manutenção da produção pesqueira e da biodiversidade. A dispersão de larvas ocorre em diferentes escalas espaciais e temporais, de forma que o recobrimento global e escala sinóptica fazem dos dados de satélite ferramentas importantes para esses estudos. O objetivo deste artigo

  16. SINOPSE DA SITUAÇÃO ATUAL, PERSPECTIVAS E CONDIÇÕES DE CULTIVO PARA LAGOSTAS PALINURIDAE REVIEW OF CURRENT SITUATION, PERSPECTIVE AND NEW TECNOLOGIES FOR GROWOUT OF PALINURID LOBSTERS

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    Marco Antonio Igarashi

    2007-07-01

    Full Text Available A lagosta é um produto de exportação de grande importância para o Nordeste brasileiro. Há uma preocupação visível e constante com o decréscimo da produção lagosteira, razão pela qual se propõe o cultivo da lagosta. Não há cultivo comercial de lagostas no Brasil e, no mundo, poucos juvenis de lagostas são cultivados em escala comercial. Desde 1995, os pesquisadores brasileiros têm feito esforços para criar a lagosta Panulirus argus e P. laevicauda, de pueruli ou juvenis recentes até adulto. Contudo, as investigações envolvem a captura dos exemplares em seu hábitat, para o posterior cultivo em confinamento. Existempossibilidades de o Estado do Ceará cultivar juvenis de P. argus e de P. laevicauda que são encontrados em profusão, porém mais pesquisas são necessárias antes de se iniciar um projeto em escala comercial. A par disso, estratégias para a criação da lagosta são relatadas detalhadamente neste artigo, objetivando contribuir para o êxito dessa atividade. Além disso, demonstra-se que os juvenis podem ser cultivados sob regime de confinamento, por se adaptarem bem às condições artificiais de alimentação. Dadas tais características, a lagosta é um crustáceo que se apresenta apropriado para o cultivo comercial. PALAVRAS-CHAVE: Cultivo, lagosta, manejo. Spiny lobster are important product of exportation in Northeastern of Brasil. There is a visible preoccupation about the reported decline in the catch of lobster. One of the solution to this problem is through culture of spiny lobster. There is no commercial juveniles growout in Brazil and the world culture of juvenile spiny lobster is still conducted on only a small commercial scale. Since 1995 Brazilian researchers have made efforts to rear spiny lobster Panulirus argus and P. laevicauda from the pueruli or early juvenile to the adult stage. The investigations involve capturing pueruli or juveniles and growing them in confinement. This possibility has

  17. LOBSTER - The Next Generation

    Science.gov (United States)

    Schwenk, Arne

    2016-04-01

    Since 1997 K.U.M. GmbH designs and manufactures Ocean Bottom Seismometer. During the last three years we designed a new instrument which is presented here. Higher resolution, higher accuracy and less power consumption led to an unique instrument, the worlds smallest broadband longterm OBS. Key data are: 32 bit, 143dB, 300mW, 120 sec, 200kg deployment weight, size of half a palette.

  18. The Color of Lobsters

    NARCIS (Netherlands)

    Wijk, Arjan van

    2005-01-01

    Synthesis of 13C-enriched carotenoids. Carotenoids are natural colorants, ranging in color from pale yellow to deep purple, with important biological functions. Carotenoids in the human diet have a beneficial health effect, playing a role in the prevention of cardiovascular disease and cancer. To

  19. Oceanographic Currents and Local Ecological Knowledge Indicate, and Genetics Does Not Refute, a Contemporary Pattern of Larval Dispersal for The Ornate Spiny Lobster, Panulirus ornatus in the South-East Asian Archipelago.

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    Hoc Tan Dao

    Full Text Available Here we utilize a combination of genetic data, oceanographic data, and local ecological knowledge to assess connectivity patterns of the ornate spiny lobster Panulirus ornatus (Fabricius, 1798 in the South-East Asian archipelago from Vietnam to Australia. Partial mitochondrial DNA control region and 10 polymorphic microsatellites did not detect genetic structure of 216 wild P. ornatus samples from Australia, Indonesia and Vietnam. Analyses show no evidence for genetic differentiation among populations (mtDNA control region sequences ΦST = -0.008; microsatellite loci FST = 0.003. A lack of evidence for regional or localized mtDNA haplotype clusters, or geographic clusters of microsatellite genotypes, reveals a pattern of high gene flow in P. ornatus throughout the South-East Asian Archipelago. This lack of genetic structure may be due to the oceanography-driven connectivity of the pelagic lobster larvae between spawning grounds in Papua New Guinea, the Philippines and, possibly, Indonesia. The connectivity cycle necessitates three generations. The lack of genetic structure of P. ornatus population in the South-East Asian archipelago has important implications for the sustainable management of this lobster in that the species within the region needs to be managed as one genetic stock.

  20. ANALISIS DAMPAK PERMEN KP RI NOMOR 1/PERMEN-KP/2015 TERHADAP PERDAGANGAN DOMESTIK ANTAR PROVINSI KOMODITI LOBSTER (Panulirus spp, KEPITING (Scylla serrata DAN RAJUNGAN (Portunus pelagicus DI KALIMANTAN SELATAN

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    Ichi Langlang Buana Machmud

    2017-05-01

    Full Text Available This study aims to (1 analyze the impact of Permen KP RI No. 1/PERMEN-KP/2015 against the decrease/increase of the amount of volume, frequency and value of interprovincial domestic trade of lobster (Panulirus spp, crab (Scylla serrata and small crab (Portunus pelagicus commodities; (2 to analyze the causes of the offense of smuggling attempts by large inter-provincial traders of lobster (Panulirus spp, crab (Scylla serrata and small crab (Portunus pelagicus commodities; and (3 to analyze the impact of Permen KP RI No.1/PERMEN-KP/2015 against the marketing channels of trade of lobster (Panulirus spp, crab (Scylla serrata and small crab (Portunus pelagicus commodities and trade organizations involved in domestic trade of the three commodities.  This thesis study activities were carried out in the province of South Kalimantan. The data collected were data sourced directly from the observation in the study site, and other supporting data relating to the object of study.  The results of this study: (1 Impact of Permen KP RI No. 1/PERMEN-KP/2015 are as follows: (a it has an effect of significantly reducing the volume, frequency and value of inter-provincial domestic trade of live crab (Scylla serrata and small fresh crab (Portunus pelagicus commodities, (b it has an effect of significantly reducing the volume and value of trade and has no significant effect on the frequency of inter-provincial domestic trade of soft-shelled crab commodity (Scylla serrata; (c it has no impact on inter-provincial domestic trade of fresh/frozen lobster commodities (Panulirus spp; (d it has no significant effect on the volume, frequency and value of inter-provincial domestic trade of crab meat (Scylla serrata, small crab meat (Portunus pelagicus, fresh/boiled crab (Scylla serrata and live lobsters (Panulirus spp commodities. (2 The occurrence of repeated violations in the form of an attempt smuggling by entrepreneurs (wholesalers of inter-provincial domestic sender of

  1. [Proceedings of the 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans, Krakow, Poland, 2013: A tribute to Pál Mihály Müller / R.H.B. Fraaije, M. Hyžný, J.W.M. Jagt, M. Krobicki & B.W.M. van Bakel (eds.)]: Miocene squat lobsters (Decapoda, Anomura, Galatheoidea) of the Central Paratethys – a review, with description of a new species of Munidopsis

    NARCIS (Netherlands)

    Hyžný, M.; Gašparič, R.; Robins, C.M.; Schlögl, J.

    2014-01-01

    All squat lobsters of the families Galatheidae, Munididae and Munidopsidae from the Miocene of the Central Paratethys are reviewed taxonomically. Based on additional observations emended diagnoses are provided for Agononida cerovensis and Galathea weinfurteri, from the Lower and Middle Miocene,

  2. [Proceedings of the 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans, Krakow, Poland, 2013: A tribute to Pál Mihály Müller / R.H.B. Fraaije, M. Hyžný, J.W.M. Jagt, M. Krobicki & B.W.M. van Bakel (eds.)]: Miocene squat lobsters (Decapoda, Anomura, Galatheoidea) of the Central Paratethys – a review, with description of a new species of Munidopsis: erratum

    NARCIS (Netherlands)

    Hyžný, M.; Gašparič, R.; Robins, C.M.; Schlögl, J.

    2015-01-01

    All squat lobsters of the families Galatheidae, Munididae and Munidopsidae from the Miocene of the Central Paratethys are reviewed taxonomically. Based on additional observations emended diagnoses are provided for Agononida cerovensis and Galathea weinfurteri, from the Lower and Middle Miocene,

  3. Spatiotemporal bioeconomic performance of artificial shelters in a small-scale, rights-based managed Caribbean spiny lobster (Panulirus argus fishery

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    Maren Headley

    2017-03-01

    Full Text Available This study presents a bioeconomic analysis of artificial shelter performance in a fishery targeting a spiny lobster meta-population, with spatially allocated, individual exclusive benthic property rights for shelter introduction and harvest of species. Insights into fishers’ short-run decisions and fishing strategies are also provided. Spatiotemporal bioeconomic performance of shelters located in ten fishing areas during four seasons was compared using two-way ANOVAs and Pearson correlations. Results show that there was spatiotemporal heterogeneity in bioeconomic variables among fishing areas, with mean catch per unit effort (CPUE, kg shelter–1 ranging from 0.42 kg to 1.3 kg per trip, mean quasi-profits of variable costs per shelter harvested ranging from USD6.00 to USD19.57 per trip, and mean quasi-profits of variable costs ranging from USD338 to USD1069 per trip. Positive moderate correlations between shelter density and CPUE (kg shelter–1 km–2 were found. Bioeconomic performance of the shelters was influenced by spatiotemporal resource abundance and distribution, fishing area location in relation to the port, shelter density, heterogeneous fishing strategies and the management system. The results provide empirical information on the spatiotemporal performance of shelters and fishing strategies and can contribute to management at the local-scale of a meta-population distributed throughout the Caribbean Sea and Gulf of Mexico.

  4. Growth and reproduction investment of the young of the year of the squat lobster Munida gregaria (Crustacea: Anomura in the Patagonian coast

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    Martin Varisco

    2015-09-01

    Full Text Available The growth and reproduction investment of the young of the year (0+ of the squat lobster Munida gregaria in San Jorge Gulf, Argentina, were analysed. Moult cycle and size frequency distribution were studied in monthly field samples. Experiments to determine moult increments and intermoult duration were conducted. Sexual maturity, fecundity and reproductive output were analysed in field samples. In addition, maturity experiments in laboratory cultures were conducted. After settlement (November, juveniles showed fast growth until winter (July and growth restarted in September-October. At the beginning of the mating period (early June, males 0+ exhibited mature gonads, whereas females 0+ only showed previtellogenic oocytes. Experimental data showed that females with developed gonads had smaller-size increments in the previous moult. Fecundity and reproductive output were significantly lower in females 0+ than in older females. The early life history of M. gregaria in San Jorge Gulf differs from that of southern populations as those of Beagle Channel and Strait of Magellan due to faster growth and early reproductive investment. Our results suggest that females 0+ of M. gregaria have two investment strategies: early maturity with low fecundity and delayed maturity with higher future fecundity.

  5. Hygienic-sanitary working practices and implementation of a Hazard Analysis and Critical Control Point (HACCP plan in lobster processing industries Condições higiênico-sanitárias e implementação do plano de Análise de Perigos e Pontos Críticos de Controle (APPCC em indústrias processadoras de lagosta

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    Cristina Farias da Fonseca

    2013-03-01

    Full Text Available This study aimed to verify the hygienic-sanitary working practices and to create and implement a Hazard Analysis Critical Control Point (HACCP) in two lobster processing industries in Pernambuco State, Brazil. The industries studied process frozen whole lobsters, frozen whole cooked lobsters, and frozen lobster tails for exportation. The application of the hygienic-sanitary checklist in the industries analyzed achieved conformity rates over 96% to the aspects evaluated. The use of the Hazard Analysis Critical Control Point (HACCP) plan resulted in the detection of two critical control points (CCPs) including the receiving and classification steps in the processing of frozen lobster and frozen lobster tails, and an additional critical control point (CCP) was detected during the cooking step of processing of the whole frozen cooked lobster. The proper implementation of the Hazard Analysis Critical Control Point (HACCP) plan in the lobster processing industries studied proved to be the safest and most cost-effective method to monitor each critical control point (CCP) hazards.Objetivou-se com este estudo verificar as condições higiênico-sanitárias e criar um plano de Análise de Perigos e Pontos Críticos de Controle (APPCC) para implantação em duas indústrias de processamento de lagosta no Estado de Pernambuco, Brasil. As indústrias estudadas processam lagosta inteira congelada, lagostas inteiras cozidas congeladas e caudas de lagosta congelada para exportação. A aplicação de um checklist de controle higiênico-sanitário nas indústrias visitadas resultou em uma classificação global de conformidades maior que 96% dos aspectos analisados. O desenvolvimento do plano APPCC resultou na detecção de dois pontos críticos de controle (PCC), incluindo o recebimento e etapas de classificação, no processamento de lagosta congelada e caudas de lagosta congelada, e um PCC adicional foi detectado no processamento de lagosta inteira cozida

  6. Invited Article: First Flight in Space of a Wide-field-of-view Soft X-Ray Imager Using Lobster-Eye Optics: Instrument Description and Initial Flight Results

    Science.gov (United States)

    Collier, Michael; Porter, F. Scott; Sibeck, David G.; Carter, Jenny A.; Chiao, Meng P.; Chomay, Dennis J.; Cravens, Thomas E.; Galeazzi, Massiniliano; Keller, John; Koutroumpa, Dimitra

    2015-01-01

    We describe the development, launch into space, and initial results from a prototype wide eld-of-view (FOV) soft X-ray imager that employs Lobster-eye optics and targets heliophysics, planetary, and astrophysics science. The Sheath Transport Observer for the Redistribution of Mass (STORM) is the rst instrument using this type of optics launched into space and provides proof-of-concept for future ight instruments capable of imaging structures such as the terrestrial cusp, the entire dayside magnetosheath from outside the magnetosphere, comets, the moon, and the solar wind interaction with planetary bodies like Venus and Mars.

  7. Invited Article: First flight in space of a wide-field-of-view soft x-ray imager using lobster-eye optics: Instrument description and initial flight results.

    Science.gov (United States)

    Collier, Michael R; Porter, F Scott; Sibeck, David G; Carter, Jenny A; Chiao, Meng P; Chornay, Dennis J; Cravens, Thomas E; Galeazzi, Massimiliano; Keller, John W; Koutroumpa, Dimitra; Kujawski, Joseph; Kuntz, Kip; Read, Andy M; Robertson, Ina P; Sembay, Steve; Snowden, Steven L; Thomas, Nicholas; Uprety, Youaraj; Walsh, Brian M

    2015-07-01

    We describe the development, launch into space, and initial results from a prototype wide field-of-view soft X-ray imager that employs lobster-eye optics and targets heliophysics, planetary, and astrophysics science. The sheath transport observer for the redistribution of mass is the first instrument using this type of optics launched into space and provides proof-of-concept for future flight instruments capable of imaging structures such as the terrestrial cusp, the entire dayside magnetosheath from outside the magnetosphere, comets, the Moon, and the solar wind interaction with planetary bodies like Venus and Mars [Kuntz et al., Astrophys. J. (in press)].

  8. Cytoarchitecture and ultrastructure of neural stem cell niches and neurogenic complexes maintaining adult neurogenesis in the olfactory midbrain of spiny lobsters, Panulirus argus.

    Science.gov (United States)

    Schmidt, Manfred; Derby, Charles D

    2011-08-15

    New interneurons are continuously generated in small proliferation zones within neuronal somata clusters in the olfactory deutocerebrum of adult decapod crustaceans. Each proliferation zone is connected to a clump of cells containing one neural stem cell (i.e., adult neuroblast), thus forming a "neurogenic complex." Here we provide a detailed analysis of the cytoarchitecture of neurogenic complexes in adult spiny lobsters, Panulirus argus, based on transmission electron microscopy and labeling with cell-type-selective markers. The clump of cells is composed of unique bipolar clump-forming cells that collectively completely envelop the adult neuroblast and are themselves ensheathed by a layer of processes of multipolar cell body glia. An arteriole is attached to the clump of cells, but dye perfusion experiments show that hemolymph has no access to the interior of the clump of cells. Thus, the clump of cells fulfills morphological criteria of a protective stem cell niche, with clump-forming cells constituting the adult neuroblast's microenvironment together with the cell body glia processes separating it from other tissue components. Bromodeoxyuridine pulse-chase experiments with short survival times suggest that adult neuroblasts are not quiescent but rather cycle actively during daytime. We propose a cell lineage model in which an asymmetrically dividing adult neuroblast repopulates the pool of neuronal progenitor cells in the associated proliferation zone. In conclusion, as in mammalian brains, adult neurogenesis in crustacean brains is fueled by neural stem cells that are maintained by stem cell niches that preserve elements of the embryonic microenvironment and contain glial and vascular elements. Copyright © 2011 Wiley-Liss, Inc.

  9. VZLUSAT-1: Nanosatellite with miniature lobster eye X-ray telescope and qualification of the radiation shielding composite for space application

    Science.gov (United States)

    Urban, Martin; Nentvich, Ondrej; Stehlikova, Veronika; Baca, Tomas; Daniel, Vladimir; Hudec, Rene

    2017-11-01

    In the upcoming generation of small satellites there is a great potential for testing new sensors, processes and technologies for space and also for the creation of large in situ sensor networks. It plays a significant role in the more detailed examination, modelling and evaluation of the orbital environment. Scientific payloads based on the CubeSat technology are also feasible and the miniature X-ray telescope described in this paper may serve as an example. One of these small satellites from CubeSat family is a Czech CubeSat VZLUSAT-1, which is going to be launched during QB50 mission in 2017. This satellite has dimensions of 100 mm × 100 mm × 230 mm. The VZLUSAT-1 has three main payloads. The tested Radiation Hardened Composites Housing (RHCH) has ambitions to be used as a structural and shielding material to protect electronic devices in space or for constructions of future manned and unmanned spacecraft as well as Moon or Martian habitats. The novel miniaturized X-ray telescope with a Lobster Eye (LE) optics represents an example of CubeSat's scientific payload. The telescope has a wide field of view and such systems may be essential in detecting the X-ray sources of various physical origin. VZLUSAT-1 also carries the FIPEX payload which measures the molecular and atomic oxygen density among part of the satellite group in QB50 mission. The VZLUSAT-1 is one of the constellation in the QB50 mission that create a measuring network around the Earth and provide multipoint, in-situ measurements of the atmosphere.

  10. Propagación in vitro de Heliconia bihai (L. cv. Lobster Salmón a partir de meristemos florales

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    Londoño-Giraldo Lina María

    2011-06-01

    Full Text Available

    Se desarrolló un protocolo de propagación in vitro a partir de meristemos florales para Heliconia bihai cv. Lobster Salmón. Para el efecto se establecieron 250 yemas florales en diferentes tiempos utilizando NaClO al 1% durante 20 min. El medio de establecimiento Murashige y Skoog con mejores resultados fue BAP (2 mg/lt, AIA (1 mg/lt y 0.1 g/lt de L-cisteína. La mayor produccion de brotes en multiplicación se obtuvo con 6 mg/lt de BAP y con un subcultivo posterior en medio con 2 mg/lt de BAP y 0.5 mg/lt de AIA, alcanzando una tasa de multiplicación de tres nuevas yemas. El enraizamiento de las plántulas in vitro se logró con 1.3 mg/lt de AIA. La aclimatación en vivero fue 92% de supervivencia. Se realizó un análisis de varianza (Anova y un test de Tukey para las variables evaluadas las cuales mostraron diferencias estadísticas en cada fase. La propagación in vitro de heliconias a partir de yemas florales requiere mayor tiempo en la fase de establecimiento y multiplicación, no obstante permite mayores porcentajes de supervivencia y una menor contaminación, ofreciendo material de siembra de diferentes especies de esta planta de interés comercial.

  11. Propagación in vitro de Heliconia bihai (L. cv. Lobster Salmón a partir de meristemos florales

    Directory of Open Access Journals (Sweden)

    Marta Leonor Marulanda-ángel

    2011-04-01

    Full Text Available Se desarrolló un protocolo de propagación in vitro a partir de meristemos florales para Heliconia bihai cv. Lobster Salmón. Para el efecto se establecieron 250 yemas florales en diferentes tiempos utilizando NaClO al 1% durante 20 min. El medio de establecimiento Murashige y Skoog con mejores resultados fue BAP (2 mg/lt, AIA (1 mg/lt y 0.1 g/lt de L-cisteína. La mayor produccion de brotes en multiplicación se obtuvo con 6 mg/lt de BAP y con un subcultivo posterior en medio con 2 mg/lt de BAP y 0.5 mg/lt de AIA, alcanzando una tasa de multiplicación de tres nuevas yemas. El enraizamiento de las plántulas in vitro se logró con 1.3 mg/lt de AIA. La aclimatación en vivero fue 92% de supervivencia. Se realizó un análisis de varianza (Anova y un test de Tukey para las variables evaluadas las cuales mostraron diferencias estadísticas en cada fase. La propagación in vitro de heliconias a partir de yemas florales requiere mayor tiempo en la fase de establecimiento y multiplicación, no obstante permite mayores porcentajes de supervivencia y una menor contaminación, ofreciendo material de siembra de diferentes especies de esta planta de interés comercial.

  12. Lipid Composition of Oil Extracted from Wasted Norway Lobster (Nephrops norvegicus Heads and Comparison with Oil Extracted from Antarctic Krill (Euphasia superba

    Directory of Open Access Journals (Sweden)

    Amaya Albalat

    2016-12-01

    Full Text Available In the UK, the Norway lobster (Nephrops norvegicus supports its most important shellfish fishery. Nephrops are sold either whole, or as “tails-only” for the scampi trade. In the “tailing” process, the “head” (cephalothorax is discarded as waste. A smaller crustacean species, the Antarctic krill Euphasia superba, represents an economically valuable industry, as its extractable oil is sold as a human dietary supplement. The aim of this study was to determine the amount and composition of the oil contained in discarded Nephrops heads and to compare its composition to the oil extracted from krill. Differences due to Geographical variation and seasonal patterns in the amount and composition of lipid were also noted. Results indicated that Nephrops head waste samples collected from more southern locations in Scotland (Clyde Sea area contained higher levels of oil when compared to samples collected from northern locations in Iceland. Moreover, seasonal differences within the Clyde Sea area in Scotland were also observed, with oil extracted from Nephrops head waste peaking at around 11.5% during the summer months when larger and more mature females were caught by trawl. At this time of the year, the valuable fatty acids eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA accounted for around 23% of the total fatty acid content in oil extracted from Nephrops head waste. A seasonal effect on EPA content was found, with higher levels obtained in the summer, while no trend was found in DHA percentages. Finally, oil from Nephrops head waste contained a higher proportion of EPA and DHA than krill oil but these fatty acids were more abundantly linked to the neutral lipids rather to than polar lipids. The characterization of lipid that could be extracted from Nephrops head waste should be seen as a first step for the commercial use of a valuable resource currently wasted. This approach is extremely relevant given the current limited supply of

  13. Monochromatic blue light entrains diel activity cycles in the Norway lobster, Nephrops norvegicus (L. as measured by automated video-image analysis

    Directory of Open Access Journals (Sweden)

    Jacopo Aguzzi

    2009-12-01

    Full Text Available There is growing interest in developing automated, non-invasive techniques for long-lasting, laboratory-based monitoring of behaviour in organisms from deep-water continental margins which are of ecological and commercial importance. We monitored the burrow emergence rhythms in the Norway lobster, Nephrops norvegicus, which included: a characterising the regulation of behavioural activity outside the burrow under monochromatic blue light-darkness (LD cycles of 0.1 lx, recreating slope photic conditions (i.e. 200-300 m depth and constant darkness (DD, which is necessary for the study of the circadian system; b testing the performance of a newly designed digital video-image analysis system for tracking locomotor activity. We used infrared USB web cameras and customised software (in Matlab 7.1 to acquire and process digital frames of eight animals at a rate of one frame per minute under consecutive photoperiod stages for nine days each: LD, DD, and LD (subdivided into two stages, LD1 and LD2, for analysis purposes. The automated analysis allowed the production of time series of locomotor activity based on movements of the animals’ centroids. Data were studied with periodogram, waveform, and Fourier analyses. For the first time, we report robust diurnal burrow emergence rhythms during the LD period, which became weak in DD. Our results fit with field data accounting for midday peaks in catches at the depth of slopes. The comparison of the present locomotor pattern with those recorded at different light intensities clarifies the regulation of the clock of N. norvegicus at different depths.

  14. Omega-3 fatty acids upregulate adult neurogenesis

    OpenAIRE

    Beltz, Barbara S.; Tlusty, Michael F.; Benton, Jeannie L.; Sandeman, David C.

    2007-01-01

    Omega-3 fatty acids play crucial roles in the development and function of the central nervous system. These components, which must be obtained from dietary sources, have been implicated in a variety of neurodevelopmental and psychiatric disorders. Furthermore, the presence of omega-6 fatty acids may interfere with omega-3 fatty acid metabolism. The present study investigated whether changes in dietary ratios of omega-3:omega-6 fatty acids influence neurogenesis in the lobster (Homarus america...

  15. Assessing Fish and Motile Fauna around Offshore Windfarms Using Stereo Baited Video.

    Directory of Open Access Journals (Sweden)

    Ross A Griffin

    Full Text Available There remains limited knowledge of how offshore windfarm developments influence fish assemblages, particularly at a local scale around the turbine structures. Considering the existing levels of anthropogenic pressures on coastal fish populations it is becoming increasingly important for developers and environmental regulators to gain a more comprehensive understanding of the factors influencing fish assemblages. Improving our ability to assess such fish populations in close proximity to structures will assist in increasing this knowledge. In the present study we provide the first trial use of Baited Remote Underwater Stereo-Video systems (stereo BRUVs for the quantification of motile fauna in close proximity to offshore wind turbines. The study was conducted in the Irish Sea and finds the technique to be a viable means of assessing the motile fauna of such environments. The present study found a mixture of species including bottom dwellers, motile crustaceans and large predatory fish. The majority of taxa observed were found to be immature individuals with few adult individuals recorded. The most abundant species were the angular crab (Goneplax rhomboides and the small-spotted catshark (Scyliorhinus canicula. Of note in this study was the generally low abundance and diversity of taxa recorded across all samples, we hypothesise that this reflects the generally poor state of the local fauna of the Irish Sea. The faunal assemblages sampled in close proximity to turbines were observed to alter with increasing distance from the structure, species more characteristic of hard bottom environments were in abundance at the turbines (e.g. Homarus gammarus, Cancer pagarus, Scyliorhinus spp. and those further away more characteristic of soft bottoms (e.g. Norwegian Lobster. This study highlights the need for the environmental impacts of offshore renewables on motile fauna to be assessed using targeted and appropriate tools. Stereo BRUVs provide one of those

  16. Rapid radiation in spiny lobsters (Palinurus spp) as revealed by classic and ABC methods using mtDNA and microsatellite data.

    Science.gov (United States)

    Palero, Ferran; Lopes, Joao; Abelló, Pere; Macpherson, Enrique; Pascual, Marta; Beaumont, Mark A

    2009-11-09

    Molecular tools may help to uncover closely related and still diverging species from a wide variety of taxa and provide insight into the mechanisms, pace and geography of marine speciation. There is a certain controversy on the phylogeography and speciation modes of species-groups with an Eastern Atlantic-Western Indian Ocean distribution, with previous studies suggesting that older events (Miocene) and/or more recent (Pleistocene) oceanographic processes could have influenced the phylogeny of marine taxa. The spiny lobster genus Palinurus allows for testing among speciation hypotheses, since it has a particular distribution with two groups of three species each in the Northeastern Atlantic (P. elephas, P. mauritanicus and P. charlestoni) and Southeastern Atlantic and Southwestern Indian Oceans (P. gilchristi, P. delagoae and P. barbarae). In the present study, we obtain a more complete understanding of the phylogenetic relationships among these species through a combined dataset with both nuclear and mitochondrial markers, by testing alternative hypotheses on both the mutation rate and tree topology under the recently developed approximate Bayesian computation (ABC) methods. Our analyses support a North-to-South speciation pattern in Palinurus with all the South-African species forming a monophyletic clade nested within the Northern Hemisphere species. Coalescent-based ABC methods allowed us to reject the previously proposed hypothesis of a Middle Miocene speciation event related with the closure of the Tethyan Seaway. Instead, divergence times obtained for Palinurus species using the combined mtDNA-microsatellite dataset and standard mutation rates for mtDNA agree with known glaciation-related processes occurring during the last 2 my. The Palinurus speciation pattern is a typical example of a series of rapid speciation events occurring within a group, with very short branches separating different species. Our results support the hypothesis that recent climate

  17. How biophysical interactions associated with sub- and mesoscale structures and migration behavior affect planktonic larvae of the spiny lobster in the Juan Fernández Ridge: A modeling approach

    Science.gov (United States)

    Medel, Carolina; Parada, Carolina; Morales, Carmen E.; Pizarro, Oscar; Ernst, Billy; Conejero, Carlos

    2018-03-01

    The Juan Fernández Ridge (JFR) is a chain of topographical elevations in the eastern South Pacific (∼33-35°S, 76-81.5°W). Rich in endemic marine species, this ridge is frequently affected by the arrival of mesoscale eddies originating in the coastal upwelling zone off central-southern Chile. The impacts of these interactions on the structure and dynamics of the JFR pelagic system have, however, not been addressed yet. The present model-based study is focused on the coupled influence of mesoscale-submesoscale processes and biological behavior (i.e., diel vertical migration) on the horizontal distribution of planktonic larvae of the spiny lobster (Jasus frontalis) around the JFR waters. Two case studies were selected from a hydrodynamic Regional Ocean Modeling System to characterize mesoscale and submesoscale structures and an Individual-based model (IBM) to simulate diel vertical migration (DVM) and its impact on the horizontal distribution and the patchiness level. DVM behavior of these larvae has not been clearly characterized, therefore, three types of vertical mechanisms were assessed on the IBM: (1) no migration (LG), (2) a short migration (0-50 m depth, DVM1), and (3) a long migration (10-200 m depth, DVM2). The influence of physical properties (eddy kinetic energy, stretching deformation and divergence) on larval aggregation within meso and submesoscale features was quantified. The patchiness index assessed for mesoscale and submesoscale structures showed higher values in the mesoscale than in the submesoscale. However, submesoscale structures revealed a higher accumulation of particles by unit of area. Both vertical migration mechanisms produced larger patchiness indices compared to the no migration experiment. DVM2 was the one that showed by far the largest aggregation of almost all the aggregation zones. Larval concentrations were highest in the submesoscale structures; these zones were characterized by low eddy kinetic energy, negative stretching

  18. Electric paralyzation and reduction of weight loss in the processing of round-cooked spiny lobsters Paralisação elétrica da lagosta e redução da perda de peso no processamento de lagosta inteira-cozida

    Directory of Open Access Journals (Sweden)

    Masayoshi Ogawa

    2007-03-01

    Full Text Available This study proposes alternatives to the current methods of processing round-cooked lobster. The paralyzation of lobsters with direct electric shock consumes 10.526 x 10-3 kWh, which is significantly less than the 11 kWh required by the traditional thermal-shock method (based on 60 kg of lobsters. A better weight gain was obtained by immersion of paralyzed lobsters in brine before cooking. Systematic trials combining 3, 6, or 9% brine concentrations with immersion periods of 15, 30, or 45 minutes were performed in order to determine the best combinations. A mathematical model was designed to predict the weight gain of lobsters of different sizes in any combination of treatments. For small lobsters, a 45 minutes immersion in 6% brine gave the best response in terms of weight gain (4.7% and cooking produced a weight loss of only 1.34% in relation to fresh lobster weight. For medium-sized lobsters, a 45 minutes immersion in 9% brine produced a weight gain of 2.64%, and cooking a weight gain of 1.08%. For large lobsters, a 45 minutes immersion in 6% brine produced a weight gain of 3.87%, and cooking a weight gain of 1.62%.O presente estudo propõe alternativas aos métodos convencionais de processamento da lagosta inteira-cozida. Para a paralisação de 60 kg de lagosta com aplicação de choque elétrico, foram consumidos 10,526 x 10-3 kWh, valor significativamente inferior aos 11 kWh requeridos pelo método tradicional de choque térmico. Um maior ganho de peso foi obtido pela imersão de lagostas paralisadas em salmoura antes do cozimento. Experimentos combinando as concentrações de salmoura a 3, 6 e 9% com os tempos de imersão de 15, 30 ou 45 minutos foram realizados. Um modelo matemático foi ajustado para predizer o rendimento de peso de lagostas de diferentes tamanhos para as combinações de tratamentos testadas. Para lagostas pequenas, um tempo de imersão de 45 minutos em salmoura a 6% apresentou a melhor resposta em termos de ganho de

  19. Comentarios sobre la distribución de la langosta pinta Panulirus inflatus y la langosta roja P. interruptus (Crustacea: Palinuridae en el Pacífico mexicano Remarks on the distribution of the pinto lobster Panulirus inflatus and the red lobster P. interruptus (Crustacea: Palinuridae in the Mexican Pacific

    Directory of Open Access Journals (Sweden)

    Ernesto Campos

    2007-06-01

    Full Text Available El trabajo de campo sobre la costa oeste de la península de Baja California entre los años 2000 y 2005 dio como resultado la ampliación del ámbito geográfico norteño, desde la Bahía de Santa María hasta Punta Eugenia y sus zonas aledañas, para una población permanente de la langosta pinta Panulirus inflatus (Bouvier, 1895. Registros de esta especie para Bahía de Los Ángeles (golfo de California e isla Guadalupe, México y San Diego, California, en Estados Unidos de América están considerados extralímite y se relacionan con el incremento en la temperatura promedio en el golfo, la condición de calentamiento del agua marina en el Pacifico oriental o el evento El Niño. Adicionalmente, un análisis histórico detallado sobre la distribución de la langosta roja P. interruptus (Randall, 1893 sugiere que los registros al sur de Bahía Magdalena, Baja California Sur y aquellos de la parte sur del Golfo de California son extralímite. Sin embargo, los individuos de Bahía de Los Ángeles y sus áreas aledañas (incluyendo Isla Tiburón y Guaymas, Sonora parecen representar una población que quedó aislada de aquella de la costa oeste de la península de Baja California después de que el corredor marino medio-peninsular, presente en el período Terciario neógeno, se cerró al emerger completamente la península.Fieldwork along the west coast of the Baja California peninsula has resulted in a northern range extension, from Bahía Santa María to Punta Eugenia and vicinity, Baja California Sur, Mexico, for a permanent population of the pinto lobster Panulirus inflatus (Bouvier, 1895. Records of this species from Ángel de la Guarda Island (within the Gulf of California and Guadalupe Island, Mexico and San Diego, California, USA are considered extralimital and related to annual water warming in the Gulf and the Eastern Pacific warm water condition or El Niño event, respectively. In addition, an historic analysis of the red lobster

  20. [Proceedings of the 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans, Krakow, Poland, 2013: A tribute to Pál Mihály Müller / R.H.B. Fraaije, M. Hyžný, J.W.M. Jagt, M. Krobicki & B.W.M. van Bakel (eds.)]: Pristinaspinidae, a new family of Cretaceous kiwaiform stem-lineage squat lobster (Anomura, Chirostyloidea)

    NARCIS (Netherlands)

    Ahyong, S.T.; Roterman, C.N.

    2014-01-01

    The chirostyloid squat lobster Pristinaspina gelasina from the Upper Cretaceous of Alaska is most closely related to members of the genus Kiwa (Kiwaidae) as indicated by the presence of supraocular spines, a medially carinate rostrum and similar carapace groove patterns. Evidence from morphology,