WorldWideScience

Sample records for sardina sardinops sagax

  1. Annual ring validation of the south african sardine Sardinops sagax ...

    African Journals Online (AJOL)

    A total of 21 sardine Sardinops sagax otoliths, collected in winter and spring 1994, were examined with a scanning electron microscope to validate growth zones using daily growth increments. Increment numbers and widths for the first, second and third annual growth zones served to back-calculate hatching dates and to ...

  2. Characterisation of purified parvalbumin from five fish species and nucleotide sequencing of this major allergen from Pacific pilchard, Sardinops sagax.

    Science.gov (United States)

    Beale, Janine E; Jeebhay, Mohamed F; Lopata, Andreas L

    2009-09-01

    IgE-mediated allergic reaction to seafood is a common cause of food allergy including anaphylactic reactions. Parvalbumin, the major fish allergen, has been shown to display IgE cross-reactivity among fish species consumed predominantly in Europe and the Far East. However, cross-reactivity studies of parvalbumin from fish species widely consumed in the Southern hemisphere are limited as is data relating to immunological and molecular characterisation. In this study, antigenic cross-reactivity and the presence of oligomers and isomers of parvalbumin from five highly consumed fish species in Southern Africa were assessed by immunoblotting using purified parvalbumin and crude fish extracts. Pilchard (Sardinops sagax) parvalbumin was found to display the strongest IgE reactivity among 10 fish-allergic consumers. The cDNA sequence of the beta-form of pilchard parvalbumin was determined and designated Sar sa 1.0101 (accession number FM177701 EMBL/GenBank/DDBJ databases). Oligomeric forms of parvalbumin were observed in all fish species using a monoclonal anti-parvalbumin antibody and subject's sera. Isoforms varied between approximately 10-13 kDa. A highly cross-reactive allergenic isoform of parvalbumin was identified and sequenced, providing a successful primary step towards the generation of a recombinant form that could be used for diagnostic and potential therapeutic use in allergic individuals.

  3. Costos metabólicos de Engraulis ringens y Sardinops sagax en relación al peso, temperatura y el nivel de actividad

    OpenAIRE

    Villavicencio R., Zoila; Muck, Peter

    1983-01-01

    El metabolismo estándar de la anchoveta es más alto que el de la sardina; en .las larvas por un factor promedio de 2.3 y por 2.1 en juveniles y adultos en el rango de temperaturas de 14-20ºC. Lo opuesto sucede en el metabolismo activo: para una velocidad de natación de un cuerpo por segundo( =metabolismo de rutina), la anchoveta adulta con un peso mayor de 20 g a 20ºC y mayor de 50 g a 14ºC gasta menos energía que la sardina de tamaños similares; incrementándose la velocidad a 3 c.p .seg a ...

  4. Worldwide, where anchovies Engraulis spp. and sardine Sardinops ...

    African Journals Online (AJOL)

    spamer

    sardine Sardinops sagax co-occur, the two species alternate in relative ... of extinction in the wild within 100 years (Croxall et al. 1996). This paper ... Abundance of this fish decreased in the 1960s and early 1970s and it was replaced by ...

  5. Anchovy Engraulis capensis and sardine Sardinops sagax currently ...

    African Journals Online (AJOL)

    spamer

    Recruitment is thought to be determined largely by ... for forecasting recruitment strength. ..... In March and April, sustained upwelling wind events ... 2 Assumes average current velocities of 10–15 cm.s–1 in a west-north-westerly direction ...

  6. Although South African sardine (or pilchard, Sardinops sagax) were ...

    African Journals Online (AJOL)

    spamer

    was based on assumed reliability of the hydroacoustic estimates of ... of uncertainties about the value of natural mortality) .... TAC only) also to the estimate of sardine recruitment from the ... of sardine recruitment from that survey: rev ad rev.

  7. The southern African sardine Sardinops sagax (also known as ...

    African Journals Online (AJOL)

    denise

    CHANGES IN ABUNDANCE OF THE NORTHERN BENGUELA SARDINE STOCK. DURING THE ... date of young fish, using standard growth rates, indi- ... and catch per unit effort (cpue) is recognized to be a ... is developed, age-based assessment models cannot be ... The methods are described in various cruise reports.

  8. The southern African sardine Sardinops sagax supports major purse ...

    African Journals Online (AJOL)

    spamer

    be caused by environmental factors such as light level and currents, as well as by ... 2 Marine & Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2, Rogge Bay 8012, Cape Town,. South Africa. 3 Institut de ..... An impression, but one that was difficult to quantify, was that the detection rate ...

  9. The 2012 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) and Pacific Sardine (Sardinops sagax) (SH1204, ME70)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC), the Fishery Resources...

  10. 2012 Joint U.S.-Canada Integrated Acoustic and Trawl Survey of Pacific Hake (Merluccius productus) and Pacific Sardine (Sardinops sagax) (SH1204, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientists from the Fishery Resource Analysis and Monitoring (FRAM) division at the NOAA Fisheries Northwest Fisheries Science Center (NWFSC), the Fishery Resources...

  11. Relaciones tróficas, espectro alimentario y ración de alimentación de las principales especies pelágicas en el verano 1996

    OpenAIRE

    Alamo, Alejandro; Navarro, Iván; Espinoza, Pepe; Zubiate, Patricia

    1996-01-01

    Se analiza la dieta de Engraulis ringens, Sardinops sagax sagax, Trachurus picturatus murphyi, Scomber japonicus peruanus durante el verano de 1996. La ración diaria se determinó mediante el modelo de SAINSBURY (1986), utilizando el Software MAXIMS y el espectro alimentario siguiendo lo descrito por HYSLOP (1980). En la anchoveta y sardina los items presa estuvieron compuestos por copépodos de los géneros Centropages, Oncaea, Eucalanus y el crustáceo planctónico Euphausia mucronata entre los ...

  12. JST Thesaurus Headwords and Synonyms: Sardinops melanostictus [MeCab user dictionary for science technology term[Archive

    Lifescience Database Archive (English)

    Full Text Available MeCab user dictionary for science technology term Sardinops melanostictus 名詞 一般 * *... * * マイワシ マイワシ マイワシ Thesaurus2015 200906029174264192 C LS05 UNKNOWN_2 Sardinops melanostictus

  13. Comparative molecular analysis of evolutionarily distant glyceraldehyde-3-phosphate dehydrogenase from Sardina pilchardus and Octopus vulgaris.

    Science.gov (United States)

    Baibai, Tarik; Oukhattar, Laila; Mountassif, Driss; Assobhei, Omar; Serrano, Aurelio; Soukri, Abdelaziz

    2010-12-01

    The NAD(+)-dependent cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12), which is recognized as a key to central carbon metabolism in glycolysis and gluconeogenesis and as an important allozymic polymorphic biomarker, was purified from muscles of two marine species: the skeletal muscle of Sardina pilchardus Walbaum (Teleost, Clupeida) and the incompressible arm muscle of Octopus vulgaris (Mollusca, Cephalopoda). Comparative biochemical studies have revealed that they differ in their subunit molecular masses and in pI values. Partial cDNA sequences corresponding to an internal region of the GapC genes from Sardina and Octopus were obtained by polymerase chain reaction using degenerate primers designed from highly conserved protein motifs. Alignments of the deduced amino acid sequences were used to establish the 3D structures of the active site of two enzymes as well as the phylogenetic relationships of the sardine and octopus enzymes. These two enzymes are the first two GAPDHs characterized so far from teleost fish and cephalopod, respectively. Interestingly, phylogenetic analyses indicated that the sardina GAPDH is in a cluster with the archetypical enzymes from other vertebrates, while the octopus GAPDH comes together with other molluscan sequences in a distant basal assembly closer to bacterial and fungal orthologs, thus suggesting their different evolutionary scenarios.

  14. Stomach Chitinase from Japanese Sardine Sardinops melanostictus: Purification, Characterization, and Molecular Cloning of Chitinase Isozymes with a Long Linker

    Directory of Open Access Journals (Sweden)

    Satoshi Kawashima

    2016-01-01

    Full Text Available Fish express two different chitinases, acidic fish chitinase-1 (AFCase-1 and acidic fish chitinase-2 (AFCase-2, in the stomach. AFCase-1 and AFCase-2 have different degradation patterns, as fish efficiently degrade chitin ingested as food. For a comparison with the enzymatic properties and the primary structures of chitinase isozymes obtained previously from the stomach of demersal fish, in this study, we purified chitinase isozymes from the stomach of Japanese sardine Sardinops melanostictus, a surface fish that feeds on plankton, characterized the properties of these isozymes, and cloned the cDNAs encoding chitinases. We also predicted 3D structure models using the primary structures of S. melanostictus stomach chitinases. Two chitinase isozymes, SmeChiA (45 kDa and SmeChiB (56 kDa, were purified from the stomach of S. melanostictus. Moreover, two cDNAs, SmeChi-1 encoding SmeChiA, and SmeChi-2 encoding SmeChiB were cloned. The linker regions of the deduced amino acid sequences of SmeChi-1 and SmeChi-2 (SmeChi-1 and SmeChi-2 are the longest among the fish stomach chitinases. In the cleavage pattern groups toward short substrates and the phylogenetic tree analysis, SmeChi-1 and SmeChi-2 were classified into AFCase-1 and AFCase-2, respectively. SmeChi-1 and SmeChi-2 had catalytic domains that consisted of a TIM-barrel (β/α8–fold structure and a deep substrate-binding cleft. This is the first study showing the 3D structure models of fish stomach chitinases.

  15. Effects of chitosan on the shelf life of marinated sardine (Sardina pilchardus fillets during refrigerated storage

    Directory of Open Access Journals (Sweden)

    Aygül Küçükgülmez

    2012-07-01

    Full Text Available This study was carried out to evaluate the effect of chitosan on chemical, colour, sensory and microbial changes of marinated sardine (Sardina pilchardus fillets. Marination solution consisted of 10% sodium chloride + 1% chitosan (dissolved in 3% acetic acid for the chitosan group, and 10% sodium chloride + 3% acetic acid solution for the control group. After the marination process, sardine fillets were packed and stored at 4ºC for 60 days. Thiobarbituric acid (TBA values were found to be lower in the chitosan group than the control group (PL*, a*, or b* values of marinated sardine fillets. According to sensory analysis, shelf life of the chitosan group was found to be ten days longer than that of the control group. Total bacteria count of two marinated groups was found to be less than 1 log CFU/g. This study concluded that sardine marination with the addition of chitosan can delay undesirable chemical changes, retard lipid oxidation, improve sensory attributes and extend the shelf life of the product during refrigerated storage.

  16. Identificación de rasgos morfológicos para una rápida diferenciación de sardina austral (Sprattus fuegensis y sardina común (Strangomera bentincki

    Directory of Open Access Journals (Sweden)

    Antonio Aranis

    2014-11-01

    Full Text Available La pesquería artesanal de cerco multiespecífica que opera en aguas interiores de Chiloé captura sardina común (Strangomera bentincki y sardina austral (Sprattus fuegensis al mismo tiempo y en la misma área. Debido a la gran similitud morfológica externa que presentan estas dos especies de peces óseos, la identificación específica en terreno es difícil, aún para observadores científicos experimentados. Por lo tanto, el objetivo de este trabajo es proponer cual o cuales rasgos morfométricos externos debiesen ser considerados para una rápida identificación de estas especies en terreno. Se analizaron 60 ejemplares de sardina común y 79 de sardina austral. Se identificaron los ejemplares a nivel de especie y se registraron las siguientes medidas: longitud total, longitud de la cabeza, preórbita, órbita y posórbita. Todas las medidas morfométricas fueron estandarizadas para evitar colinealidad. Las diferencias en las medidas morfométricas entre especies fueron probadas mediante métodos estadísticos multivariados que incluyen el análisis de componentes principales, análisis de varianza y covarianza (ANOVA y ANCOVA, análisis multivariado de covarianza (MANOVA y análisis lineal discriminante. La medida posórbita fue el rasgo morfométrico que presentó mayor diferenciación entre especies. Se concluye que la medida de posórbita es por sí sola un carácter morfométrico externo que permitiría una rápida identificación de estas especies en terreno. Los resultados de esta investigación pueden ser tomados como línea base para la generación de guías de campo que apoyen el trabajo de identificación de especies de los observadores científicos.

  17. Reconstruction of trophic pathways between plankton and the North Iberian sardine (Sardina pilchardus using stable isotopes

    Directory of Open Access Journals (Sweden)

    Antonio Bode

    2004-03-01

    Full Text Available Feeding on phyto- and zooplankton by juvenile (< 1 year old and adult sardines (Sardina pilchardus was inferred from analyses of natural abundance of stable carbon and nitrogen isotopes in samples from the northwestern Iberian Peninsula (Spain collected at the beginning of the upwelling season and peak spawning period of sardine. Plankton samples were fractionated through nets of 20, 200, 500, 1000 and 2000 ?m mesh-size and the muscle protein of individual sardines was isolated before isotopic determinations. Up to six planktonic components and two sardine feeding types were identified from the modes in the frequency distributions of isotope abundance values. Also, the most probable pathways for carbon and nitrogen flows between compartments were analysed. The resulting food web revealed a relatively large degree of omnivory, both in plankton and sardine components, which confirms that complex trophic interactions could also occur in pelagic upwelling ecosystems. Young sardines had isotope abundance values clustered around a single mode in the frequency distribution, while adult sardines displayed two main modes. These modes are interpreted as representative of two extreme feeding types: one related to the individual capture of zooplankton prey and the other to unselective filter-feeding. Although both types of feeding could include micro- (20-200 ?m and mesozooplankton (200-2000 ?m prey, phytoplankton appears to be ingested mainly by filter-feeding. However, even adult sardines must be mainly zoophagous to achieve the observed isotopic abundance values, taking into account current assumptions on stable isotope enrichment through trophic levels. From the differences in the resulting pathways using either carbon or nitrogen isotopes, we interpreted that sardines acquire most of the protein nitrogen from zooplankton while a substantial fraction of their carbon would derive from phytoplankton. These interpretations agree with the information

  18. Sardine (Sardina pilchardus) larval dispersal in the Iberian upwelling system, using coupled biophysical techniques

    Science.gov (United States)

    Santos, A. M. P.; Nieblas, A.-E.; Verley, P.; Teles-Machado, A.; Bonhommeau, S.; Lett, C.; Garrido, S.; Peliz, A.

    2018-03-01

    The European sardine (Sardina pilchardus) is the most important small pelagic fishery of the Western Iberia Upwelling Ecosystem (WIUE). Recently, recruitment of this species has declined due to changing environmental conditions. Furthermore, controversies exist regarding its population structure with barriers thought to exist between the Atlantic-Iberian Peninsula, Northern Africa, and the Mediterranean. Few studies have investigated the transport and dispersal of sardine eggs and larvae off Iberia and the subsequent impact on larval recruitment variability. Here, we examine these issues using a Regional Ocean Modeling System climatology (1989-2008) coupled to the Lagrangian transport model, Ichthyop. Using biological parameters from the literature, we conduct simulations that investigate the effects of spawning patchiness, diel vertical migration behaviors, and egg buoyancy on the transport and recruitment of virtual sardine ichthyoplankton on the continental shelf. We find that release area, release depth, and month of release all significantly affect recruitment. Patchiness has no effect and diel vertical migration causes slightly lower recruitment. Egg buoyancy effects are significant and act similarly to depth of release. As with other studies, we find that recruitment peaks vary by latitude, explained here by the seasonal variability of offshore transport. We find weak, continuous alongshore transport between release areas, though a large proportion of simulated ichthyoplankton transport north to the Cantabrian coast (up to 27%). We also show low level transport into Morocco (up to 1%) and the Mediterranean (up to 8%). The high proportion of local retention and low but consistent alongshore transport supports the idea of a series of metapopulations along this coast.

  19. Optimization of a chemical method for skinning of sardines (Sardina pilchardus during canning processing

    Directory of Open Access Journals (Sweden)

    Manuela Vaz Velho

    2014-06-01

    Full Text Available Most of sardine (Sardina pilchardus catches is used for canning purposes. The most common product presentation is a beheaded sardine with skin and bones packed in a tin can. Canned sardines can also be presented skinless and boneless. For this last type of product, after beheading and evisceration, sardines are placed in trays, cooked and then skinned by hand, one by one, and placed in the tins, a process involving high labour costs. The aim of this work was to develop a chemical process for peeling raw sardines and its subsequent application in a canning industry processing line just after the beheading and evisceration step and before cooking. Potassium hydroxide treatments (pellets a.r. 85% KOH were applied at concentrations of 2, 3 and 4% (v/v, distilled water. Frozen sardines were beheaded and eviscerated after thawing and immersed in the different potassium hydroxide solutions at 93ºC (pH respectively 13, 13 and 13.02 for 3 min and further washed with distilled water at 100°C. In this first set of experiments, fat sardines were used (average of 9.86% of fat, w/w. The best performance, with respect to skin removal, was achieved with the 2% potassium hydroxide immersion (pH 13. With this treatment the skin was totally removed after immersion. With the other tested concentrations portions of skin were always visible and in some cases changes in texture with breakdown of muscle structure and changes of colour occurred. It was decided to perform a second set of experiments using the 2% KOH treatment, but this time applied to low fat sardines (average of 4.77% of fat, w/w, following the same subsequent procedures. The results showed that the lower fat sardines are more prone to surface changes of colour and major muscle breaks than fat sardines after the potassium hydroxide treatment. In the canning industry for this type of product (skinless and boneless only fat sardines are used to assure the total removal of skin. This treatment of 2% KOH

  20. Evaluating fishermen's conservation attitudes and local ecological knowledge of the European sardine (Sardina pilchardus), Peniche, Portugal.

    Science.gov (United States)

    Braga, Heitor O; Azeiteiro, Ulisses M; Oliveira, Henrique M F; Pardal, Miguel A

    2017-05-05

    European sardines are an important fishing resource in the North Atlantic. Recognized for its great commercial and economic value in southern Europe, this resource currently has low stock indices. From this perspective, fishers' local ecological knowledge (LEK) is appreciated as an auxiliary tool in the management of sardines in this region. Our goal is to evaluate the LEK and attitudes towards the conservation of Sardina pilchardus in the typical fishing village of Peniche, Portugal. From June to September 2016, we carried out 87 semi-structured interviews. The four main points of the interviews were interviewee profile, fishing structure, fishermen's LEK and attitudes towards sardine conservation. The interviews were qualitatively and quantitatively analyzed using a 3-point Likert scale. An LEK index and an attitude index were generated. Comparison analyses and correlations were made between the indices and variables of the interviewee profile and the fishing structure. The mean LEK index was 0.55 and was classified as moderate. The attitudes index in relation to conservation was 0.76 and was classified as positive. This index had a positive and significant correlation with the LEK index and a significant negative correlation with the fishermen's age. When the LEK index was compared with the educational level, significant differences were observed only between class A and class C. The result showed that the differences in the attitudes index were statistically significant when the three educational classes were compared. The fishermen of Peniche in Portugal present moderate informal knowledge about the biology and ecology of sardines. Attitudes towards conservation were predominantly positive. Fishermen with greater LEK, with a higher educational level and at a younger age presented more positive attitudes in relation to environmental conservation issues in the present case of the sardine population. The LEK is not necessarily related to the educational level of

  1. Food safety considerations in relation to Anisakis pegreffii in anchovies (Engraulis encrasicolus) and sardines (Sardina pilchardus) fished off the Ligurian Coast (Cinque Terre National Park, NW Mediterranean).

    Science.gov (United States)

    Serracca, Laura; Battistini, Roberta; Rossini, Irene; Carducci, Annalaura; Verani, Marco; Prearo, Marino; Tomei, Laura; De Montis, Gabriella; Ercolini, Carlo

    2014-11-03

    Engraulis encrasicolus and Sardina pilchardus are pelagic fishes of notable economic and gastronomic importance in the northwest Mediterranean (Ligurian Sea, Italy). The consumption of thermally unprocessed or lightly processed, marinated or salted anchovies and sardines presents a potential risk to acquire anisakiasis, a fish-borne parasitic disease in humans. Prevalence and abundance of Anisakis larvae in Engraulis encrasicolus and Sardina pilchardus from the Monterosso fishing grounds (Cinque Terre National Park, Ligurian Sea, Italy) were assessed, and the larvae were identified by morphological and PCR-RFLP methods. Anisakis larvae, all belonging to Anisakis pegreffii spp. were found in the visceral mass of 1050 anchovies (0.8% overall prevalence), whereas no Anisakis larvae were found in the 750 sardines examined. According to these data, the risk of acquiring anisakiasis from the consumption of raw or undercooked anchovies and sardines caught in the fishing area we investigated is very low. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Effect of the Gamma Radiation and Temperature on Histamine Production, Lipid Peroxidation and Antioxidant Parameters in Sardine (Sardina Pilchardus)

    International Nuclear Information System (INIS)

    Maltar-Strmecki, N.; Aladrovic, J.; Dzaja, P.; Ljubic-Beer, B.; Laskaj, R.

    2013-01-01

    Radiation processing of fish is recognized as a safe and effective method for reducing microorganisms and viruses as well for inactivating pathogens among the existing technologies for preservation. Safety and hygienic quality is directly related to the duration between when the fish is caught and when it reaches the end consumer and depends upon conditions how the sardine is handled and upon which conditions. As sardine (Sardina pilchardus Walbaum, 1792) is pelagric fish widely distributed in the Adriatic Sea and one of the most commercially important fish species in the fisheries of all countries located along the coast of the Adriatic Sea in the present study, the effects of gamma irradiation on the histamine production, lipid peroxidation and antioxidant parameters in sardine during the storage at two different temperatures (4 and 30 degrees of Celsius) were investigated. The results indicate that histamine concentration was reduced by gamma irradiation and that the safe consumption can be prolonged for both temperatures of storage. However, irradiation treatment induced oxidative damage, as evidenced by changes in levels of lipid peroxidation and radical kinetic rate detected by EPR (electron paramagnetic resonance) spectroscopy. These results suggest that gamma radiation undoubtedly induces antioxidant defence system in sardine fish. However, further research is necessary to elucidate the precise role that the antioxidant system plays under the influence of gamma radiation and temperature.(author)

  3. Assessment of the sardine (Sardina pilchardus Walbaum, 1792 fishery in the eastern Mediterranean basin (North Aegean Sea

    Directory of Open Access Journals (Sweden)

    K. ANTONAKAKIS

    2011-06-01

    Full Text Available The aim of this study was to describe the biometric characteristics of the European sardine (Sardina pilchardus catches and assess the current status of sardine stock in North Aegean Sea based on population characteristics and abundance trends. The stock was dominated by age groups 1 and 2, not exceeding age group 4. The sardine stock in this area was assessed through an Integrated Catch-at-Age model which implements a separable Virtual Population Analysis on catch at age data with weighted tuning indices. Sardine landings data derived from the commercial purse seine fishery over the period 2000-2008 were combined with the age structure of the stock as resulted from fisheries independent acoustic surveys. Sensitivity analysis of the impact of natural mortality values on stock assessment results was applied. Additionally forecast of the sardine population parameters and catches under different exploitation scenarios was implemented in a medium term basis. Results indicated that the North Aegean Sea sardine stock is considered fully exploited with the fishery operating close but over the empirical exploitation level for sustainability. Finally, the status of the sardine stock in N. Aegean Sea is discussed in relation to the sardine stocks from the western and the central Mediterranean basin.

  4. Biochemical and physiological modifications in tissues of Sardina pilchardus: spatial and temporal patterns as a baseline for biomonitoring studies

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    Bruno Silva Nunes

    2015-02-01

    Full Text Available Sardina pilchardus is a marine species common in the North Atlantic Ocean, and is subjected to diffuse anthropogenic chemical contamination and seasonal fluctuations in biotic and abiotic parameters that may alter its physiology and condition. Biological material is easily available through commercial fisheries, which could facilitate its use as a bioindicator species. The aim of the present work was to address its potential inclusion in biomonitoring studies, considering a combinatory approach through the use of enzymatic biomarkers and somatic indices, by assessing spatial and temporal patterns in a metapopulation along the west coast of Portugal. Our results showed significant variability of the biochemical and physiological profile of the fish, mainly concordant between sampling sites. Large differences for most markers were found across periods of the year, showing the importance of seasonality, which was mostly related to the reproductive cycle. Hence, environmental scientists should acknowledge seasonality as a strong driving force for physiological adaptations, influencing biochemical markers that are normally used to identify effects of chemical contamination. The here-obtained set of data suggests that S. pilchardus may be successfully included in oceanic biomonitoring studies, when one considers that the contribution of seasonal factors may exceed the influence of eventual anthropogenic contamination.

  5. Effect of different types of coatings on texture and nutritional properties of canned Portuguese sardines (Sardina pilchardus

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    Rita Pinheiro

    2014-06-01

    Full Text Available Canned foods have a long history of success and are likely to remain popular for the foreseeable future owing to their convenience, long shelf life and economy. Interest in fish consumption has increased in recent years due to the wide range of its health benefits. In addition to fresh product, canned fish enables a delayed consumption of this appreciated kind of food. Among the different types of fish, in Portugal, the most used in canning manufacture are sardines, tuna, anchovies, mackerels. Vegetable oils and tomato sauce are usually adopted as coatings (liquid medium. In fact, oil has a preserving effect and contributes to make the product more palatable. Its protective action lies in the ability to insulate products from air, rather than having an active bacteriostatic or bactericidal action. Among the different types of coatings the most commonly used in canning are: olive oil, seed oils and different sauces, such as tomato sauce. Tomato sauce has also vegetable oil on its formulation. The amount of coating substance can affect the nutritional composition as well as texture properties of the sardines. The aim of this work was to investigate the effect of different types of coatings on texture and nutritional properties of whole, skinless and boneless canned Portuguese Sardines (Sardina pilchardus. An experimental investigation was carried out to assess the protein, lipid, carbohydrates and ash content, texture and colour profile of canned sardine with different kinds of coatings: olive oil, sunflower oil and tomato sauce. The obtained results showed that protein and carbohydrates content were not significantly influenced by the coating used, varying between 5%-8% and13%-18%, respectively. For the moisture content it was found that the samples with tomato sauce were 2.2-fold higher than the samples with sunflower oil, and 1.3-fold higher than the samples with olive oil, independently of being whole, skinless or boneless sardine. As

  6. Sardine (sardina Pilchardus) Larval Dispersal in Northern Canary Current Upwelling System (iberian Peninsula), Using Coupled Biophysical Techniques

    Science.gov (United States)

    Santos, A. M. P. A.; Nieblas, A. E.; Verley, P.; Teles-Machado, A.; Bonhommeau, S.; Lett, C.; Garrido, S.; Peliz, A.

    2017-12-01

    The European sardine (Sardina pilchardus) is the most important small pelagic fishery of the Western Iberia Upwelling Ecosystem (WIUE). Recently, recruitment of this species has declined due to changing environmental conditions. Furthermore, controversies exist regarding its population structure with barriers thought to exist between the Atlantic-Iberian Peninsula, Northern Africa, and the Mediterranean. Few studies have investigated the transport and dispersal of sardine eggs and larvae off Iberia and the subsequent impact on larval recruitment variability. Here, we examine these issues using a Regional Ocean Modeling System climatology (1989-2008) coupled to the Lagrangian transport model, Ichthyop. Using biological parameters from the literature, we conduct simulations that investigate the effects of spawning patchiness, diel vertical migration behaviors, and egg buoyancy on the transport and recruitment of virtual sardine ichthyoplankton on the continental shelf. We find that release area, release depth, and month of release all significantly affect recruitment. Patchiness has no effect and diel vertical migration causes slightly lower recruitment. Egg buoyancy effects are significant and act similarly to depth of release. As with other studies, we find that recruitment peaks vary by latitude, explained here by the seasonal variability of offshore transport. We find weak, continuous alongshore transport between release areas, though a large proportion of simulated ichthyoplankton transport north to the Cantabrian coast (up to 27%). We also show low level transport into Morocco (up to 1%) and the Mediterranean (up to 8%). The high proportion of local retention and low but consistent alongshore transport supports the idea of a series of metapopulations along this coast. This study was supported by the Portuguese Science and Technology Foundation (FCT) through the research project MODELA (PTDC/MAR/098643/2008) and MedEx (MARIN-ERA/MAR/0002/2008). MedEx is also a

  7. Chemical Profile, Antibacterial and Antioxidant Activity of Algerian Citrus Essential Oils and Their Application in Sardina pilchardus

    Directory of Open Access Journals (Sweden)

    Djamel Djenane

    2015-06-01

    Full Text Available Stored fish are frequently contaminated by foodborne pathogens. Lipid oxidation and microbial growth during storage are also important factors in the shelf-life of fresh fish. In order to ensure the safety of fish items, there is a need for control measures which are effective through natural inhibitory antimicrobials. It is also necessary to determine the efficacy of these products for fish protection against oxidative damage, to avoid deleterious changes and loss of commercial and nutritional value. Some synthetic chemicals used as preservatives have been reported to cause harmful effects to the environment and the consumers. The present investigation reports on the extraction by hydrodistillation and the chemical composition of three citrus peel essential oils (EOs: orange (Citrus sinensis L., lemon (Citrus limonum L. and bergamot (Citrus aurantium L. from Algeria. Yields for EOs were between 0.50% and 0.70%. The chemical composition of these EOs was determined by gas chromatography coupled with mass spectrometry (GC/MS. The results showed that the studied oils are made up mainly of limonene (77.37% for orange essential oil (EO; linalyl acetate (37.28%, linalool (23.36%, for bergamot EO; and finally limonene (51.39%, β-pinene (17.04% and γ-terpinene (13.46% for lemon EO. The in vitro antimicrobial activity of the EOs was evaluated against Staphylococcus aureus (S. aureus using the agar diffusion technique. Results revealed that lemon EO had more antibacterial effects than that from other EOs. Minimal inhibitory concentrations (MICs showed a range of 0.25–0.40 μL/mL. Lemon and bergamot citrus peel EOs were added at 1 × MIC and 4 × MIC values to Sardina pilchardus (S. pilchardus experimentally inoculated with S. aureus at a level of 3.5 log10 CFU/g and stored at 8 ± 1 °C. The results obtained revealed that the 4 × MIC value of bergamot reduced completely the growth of S. aureus from day 2 until the end of storage. The presence of EOs

  8. Análisis socioeconómico e interrelación de las pesquerías de sardina y atún aleta azul en la región noroeste de México

    Directory of Open Access Journals (Sweden)

    Raúl Jesús del Moral-Simanek

    2010-01-01

    Full Text Available El establecimiento de las engordas de atún aleta azul en las costas de Baja California cambió el destino de las capturas de sardina, ya que antes se destinaban al mercado de congelados y a la elaboración de harina de pescado, y en la actualidad se utilizan como alimento para el atún aleta azul. Esto generó un efecto socioeconómico positivo para los armadores y pescadores de pelágicos menores, ya que la llegada de grandes capitales foráneos para el desarrollo de las engordas de atún mejoró los precios de la sardina, e hizo más rentable su pesquería.

  9. Coupling between the environment and the pelagic resources exploited off northern Chile: ecosystem indicators and a conceptual model Acoplamiento entre el ambiente y los recursos pelágicos explotados en el norte de Chile: un modelo conceptual

    Directory of Open Access Journals (Sweden)

    Eleuterio Yáñez

    2008-01-01

    pesquería de anchoveta (Engraulis ringens; en tanto, desde mediado de los 70's los desembarques de sardina (Sardinops sagax aumentan notablemente. Un segundo cambio de régimen se observa a finales de los 80's, representado principalmente por la notable recuperación de anchovy y disminución de sardina. Se presenta un modelo conceptual integrador de los diferentes fenómenos locales y de gran escala que afectan el ambiente marino del norte de Chile, y la distribución y abundancia de recursos pelágicos. El modelo considera análisis de datos ambientales y bio-pesqueros a distintas escalas, y describe como las fluctuaciones interdecadales (asociadas a cambios de régimen e interanuales (asociadas a los eventos El Niño del Pacífico Ecuatorial se manifiestan en el Pacífico Sur Oriental y por tanto en la zona norte de Chile, afectando el ciclo anual, la dinámica de las ondas atrapadas a la costa y la surgencia costera. En este marco, las fluctuaciones interdecadales estarían jugando un rol importante en la secuencia del reemplazo anchoveta-sardina-anchoveta.

  10. La pesca de sardina, Sardinella aurita (Teleostei: Clupeidae asociada con la variabilidad ambiental del ecosistema de surgencia costera de Nueva Esparta, Venezuela

    Directory of Open Access Journals (Sweden)

    Leo W González

    2007-03-01

    Full Text Available Se comparó la pesca de sardina (Sardinella aurita con algunos parámetros climáticos y meteorológicos del ecosistema de surgencia costera de El Morro, Nueva Esparta, Venezuela. Para el período 1996-2000, se aplicaron los modelos de regresión lineal simple y múltiple a los datos de captura en función de la velocidad del viento, temperatura superficial del mar, temperatura del aire y pluviosidad. Hubo una correlación positiva de la captura con la velocidad del viento, y una negativa con temperatura superficial del mar, temperatura del aire y pluviosidad. El modelo de regresión múltiple con intercepto mostró un ajuste bajo, por tal razón se aplicó un modelo de regresión sin intercepto, el cual mejoró significativamente el ajuste. También se aplicó el método de selección de variables "hacia adelante", encontrándose que las variables independientes viento y temperatura del aire guardan relación significativa con la captura de sardina a tiempo real (pAssociation of sardine fishery, Sardinella aurita (Teleostei: Clupeidae and environmental variability of the coastal upwelling ecosystem of Nueva Esparta, Venezuela. The present research is an analysis of Spanish sardine fishing (Sardinella aurita associated with some climatic and meteorologic parameters of the ecosystem from El Morro Nueva Esparta, Venezuela. The catch and environmental data from the area were taken in the period 1996-2000. Catch data as a function of wind speed, sea surface temperature, air temperature and rain were analyzed by means of simple lineal regression and multiple models. We found a positive correlation of catch with wind speed, and a negative correlation with sea surface temperature, air temperature, and rain. The multiple regression model with intercept had a poor fit, therefore, we made a model without intercept, which improve greatly the fit. A selection of the variables using the forward procedure verified that the independent variables "wind speed

  11. Characterising and comparing the spawning habitats of anchovy ...

    African Journals Online (AJOL)

    The spawning habitats of anchovy Engraulis encrasicolus and sardine Sardinops sagax in the southern Benguela upwelling ecosystem were characterised by comparing their egg abundances with environmental variables measured concomitantly during two different survey programmes: the South African Sardine and ...

  12. Variable spatial structure of schooling pelagic fish off Namibia ...

    African Journals Online (AJOL)

    Schools of horse mackerel Trachurus trachurus capensis, sardine Sardinops sagax and round herring Etrumeus whiteheadi were surveyed by conventional echo-integration along systematic transects. The transects were surveyed twice, in opposite directions. Clupeoid biomass was concentrated in a few dense ...

  13. Breeding success of African penguins Spheniscus demersus at ...

    African Journals Online (AJOL)

    The reproductive success of African penguins Spheniscus demersus at Dassen Island from 1994 to 2000 was variable, but much higher than previously reported figures for the species. Breeding success was positively related to the abundance of anchovy Engraulis encrasicolus and sardine Sardinops sagax, and the high ...

  14. A model of trophic flows in the northern Benguela upwelling system ...

    African Journals Online (AJOL)

    Ultimately, this type of model may form a basis for multispecies management approaches in the region. By the 1980s, sardine Sardinops sagax and hake Merluccius spp. stocks in the northern Benguela had both undergone a decline, yet were still heavily fished. Horse mackerel Trachurus trachurus capensis had increased ...

  15. Comparison of trends in abundance of guano-producing seabirds in ...

    African Journals Online (AJOL)

    The abundant guano-producing seabirds in Peru and southern Africa feed mainly on the large populations of anchovy Engraulis spp. and sardine Sardinops sagax supported by the Humboldt and Benguela upwelling systems. Numbers of guanay cormorants Phalacrocorax bougainvillii in Peru and the breeding population ...

  16. Influence of oceanographic fronts and low oxygen on the distribution ...

    African Journals Online (AJOL)

    The horizontal and vertical distributions of eggs and larvae of sardine Sardinops sagax, anchovy Engraulis encrasicolus and horse mackerel Trachurus trachurus capensis were examined in relation to distribution patterns of temperature, salinity and dissolved oxygen. Samples were collected during February–March 2002 ...

  17. Spatial variability in branchial basket meristics and morphology of ...

    African Journals Online (AJOL)

    We examined spatial variability in meristic and morphological characteristics of the branchial basket of sardine Sardinops sagax collected from four geographical regions around the southern African coast, namely Namibia and the South African west, south and east coasts. Our analysis tested the hypothesis of three putative ...

  18. The importance of lipid-rich fish prey for Cape gannet chick growth : are fishery discards an alternative?

    NARCIS (Netherlands)

    Mullers, Ralf H. E.; Navarro, Rene A.; Crawford, Robert J. M.; Underhill, Les G.

    2009-01-01

    A recent decline in population numbers of Cape gannets (Morus capensis) breeding off the west coast of South Africa coincided with decreased availability of lipid-rich fish prey: anchovy (Engraulis encrasicolus) and sardine (Sardinops sagax). Seabirds can use fishery discards as an alternative, but

  19. Tropical South-East Atlantic response to ENSO as an ecosystem ...

    African Journals Online (AJOL)

    Cases were selected based on indices of Pacific sea surface temperature and South-East African rainfall. ... an El Niño event, and higher sardine Sardinops sagax catches tend to follow a La Niña event, through the northward and southward shift respectively of the South Atlantic anticyclone and attendant coastal upwelling.

  20. Ecosystem considerations of the KwaZulu-Natal sardine run ...

    African Journals Online (AJOL)

    The annual winter sardine run along the South African east coast impacts the KwaZulu-Natal (KZN) coastal system in a variety of ways. These include ecological impacts, such as enrichment of a largely oligotrophic environment, competition between migrant sardine Sardinops sagax, other migrant and resident small ...

  1. Revised estimates of abundance of South African sardine and ...

    African Journals Online (AJOL)

    Hydro-acoustic surveys have been used to provide annual estimates of May recruitment and November spawner biomass of the South African sardine Sardinops sagax and anchovy Engraulis encrasicolus resources since 1984. These time-series of abundance estimates form the backbone of the assessment of these ...

  2. The impact of enterocin AS-48 on the shelf-life and safety of sardines (Sardina pilchardus) under different storage conditions.

    Science.gov (United States)

    Ananou, S; Zentar, H; Martínez-Bueno, M; Gálvez, A; Maqueda, M; Valdivia, E

    2014-12-01

    The purpose of this study was to determine the effect of enterocin AS-48, packaged under normal atmosphere (NA), vacuum (VP) or modified atmosphere (MAP) on the shelf life and safety of fresh sardines (Sardina pilchardus) stored at 5 °C. We studied the effect of these hurdles, alone or combined, on the relevant autochthonous bacterial populations. Total volatile basic nitrogen (TVB-N) content was used as indicative of freshness. Levels of biogenic amines cadaverine, putrescine, tyramine, and histamine were also determined. The application of AS-48 did not reduce the mesophilic, psychrotrophic, or Gram negative bacteria viable cell counts under any of the storage conditions tested. AS-48 did cause significant reductions in viable staphylococci counts, especially under VP. In sardines under NA treated with AS-48, the populations of histamine- and tyramine-forming total and lactic acid bacteria (LAB) showed no significant reductions. MAP or VP with AS-48 allowed reductions (significant at some storage times) in histamine- and tyramine-forming LAB. The TVB-N content was also reduced under normal atmosphere and, especially, in sardines stored under MAP. The most interesting results are those concerning the decrease (by several fold) in the levels of the biogenic amines cadaverine, putrescine, tyramine, and histamine determined after treatment with AS-48. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. What can otolith shape analysis tell us about population structure of the European sardine, Sardina pilchardus, from Atlantic and Mediterranean waters?

    Science.gov (United States)

    Jemaa, Sharif; Bacha, Mahmoud; Khalaf, Gaby; Dessailly, David; Rabhi, Khalef; Amara, Rachid

    2015-02-01

    The European sardine, Sardina pilchardus, exhibits a complex population structure, which has produced conflicting results in previous genetic studies. Despite its importance in the fisheries industry, stock delineation for management and conservation purposes is still a matter of debate throughout the distribution range of the species. This study examines whether otolith shapes are more efficient than genetic markers to detect population structure in pelagic species with large population sizes. Sardines were analyzed from 15 sampling localities in the Northeast Atlantic and Mediterranean Sea covering almost the whole distribution range of the species. A combination of otolith shape indices and elliptic Fourier descriptors was investigated by multivariate statistical procedures. Within the studied area, three distinct groups were identified with an overall correct classification of 77%. Group A: northern Mediterranean Sea and Gulf of Gabès; group B: Atlantic Morocco-south Alboran-Algero-provençal coasts; and group C: European Atlantic coast. The Almeria-Oran front and the Gibraltar strait are not an efficient barrier for sardine population separation as there seems to be exchanges between populations of the south-western Mediterranean Sea and those of the Moroccan Atlantic Ocean coast or Gulf of Cadiz. The results are discussed in relation to environmental conditions, oceanographic features, and physical barriers to dispersal in the study area, and compared with those obtained by previous genetic, morphometric, and meristic data. For pelagic species with high gene flow, present results highlighted the need to take into account the identification of phenotypic stocks to ensure sustainable fishery benefits and efficient conservation as they may have unique demographic properties and responses to exploitation.

  4. Biomasa acústica y distribución del jurel Trachurus murphyien el Perú

    Directory of Open Access Journals (Sweden)

    Marceliano Segura

    2013-10-01

    Full Text Available Se analizan los resultados de las evaluaciones hidroacústicas del recurso jurel Trachurus murphyi Nichols 1920 realizadas en aguas peruanas entre 1983 – 2012. Desde 1983 se incluyó al T. murphyicomo especie de estudio durante los cruceros de evaluación de recursos pelágicos ejecutados por el Instituto del Mar del Perú. Debido al énfasis en la estimación de biomasa de la anchoveta Engraulis ringens y de la sardina Sardinops sagax cuando esta última es más abundante, los cruceros se llevan a cabo durante el verano austral y las áreas de evaluación están circunscritas a las zonas más costeras hasta 100 mn, con sólo algunas exploraciones en otras estaciones y hasta 200 millas. El máximo valor de biomasa de 8.51 millones de toneladas de T. murphyien aguas peruanas estimado con las evaluaciones hidroacústicas fue encontrado durante el crucero realizado en otoño (marzo-mayo de 1983. En los años siguientes los estimados de biomasa acústica fluctuaron entre 180 mil toneladas en 1985 y otro máximo de 8.47 millones de toneladas en 1993, para luego disminuir gradualmente hasta un mínimo de 1239 t en 2010, con una ligera recuperación en los años 2011 y 2012. El área de distribución de T. murphyifue muy fluctuante en todo el periodo observado.

  5. Medidas de conservación y ordenación pesquera del jurel Trachurus murphyien el Perú

    Directory of Open Access Journals (Sweden)

    Jorge Zuzunaga

    2013-10-01

    Full Text Available Las pesquerías peruanas como actividades realizadas sobre recursos naturales renovables son reguladas por un marco jurídico, cuyo objetivo es asegurar su conservación y uso sostenible. La Ley General de Pesca (DL N°. 25977 señala que para cada tipo de pesquería y según la situación del recurso explotado debe establecerse un sistema de ordenamiento que concilie el principio de sostenibilidad de los recursos pesqueros o conservación en el largo plazo, con la obtención de los mayores beneficios económicos y sociales. En el ordenamiento pesquero del jurel Trachurus murphyi, las medidas incluyen entre otras, el régimen de acceso constituido por las autorizaciones de incremento de flota y permisos de pesca, que se otorgan solo a los buques cuyas capturas son destinadas únicamente para el consumo humano directo, de acuerdo a lo dispuesto en el Reglamento de Ordenamiento Pesquero (DS N.° 011-2007-PRODUCE. La obligación de destinar los recursos sardina Sardinops sagax, jurel T. murphyiy caballa Scomber japonicus al consumo humano directo rige desde septiembre 2002 (DS N°. 001-2002-PRODUCE. Otras medidas vigentes restringen el tamaño mínimo de malla de las redes, prohíben la captura de ejemplares menores de 31 cm de longitud total, determinan el inicio y cierre de las temporadas de pesca, los límites de captura o cuotas anuales. Estas disposiciones son complementadas por medidas de seguimiento, control y vigilancia para la efectiva conservación y uso sostenido del recurso.

  6. The Benguela upwelling ecosystem lies adjacent to the south ...

    African Journals Online (AJOL)

    denise

    increase, but it is still below the levels of the early ... variability but no trends in either subsystem, and the seasonal pattern was similar for both ..... good spatial coverage of sardine landings, with a sig- ..... periods of simultaneous change in environmental pa- ..... monotypic sardines, Sardina and Sardinops: their taxonomy,.

  7. Fritura de filetes de sardinas congeladas en aceite de oliva. Influencia de diferentes métodos de descongelación sobre el contenido graso y la composición en ácidos grasos

    Directory of Open Access Journals (Sweden)

    Álvsarez-Pontes, M. E.

    1994-06-01

    Full Text Available To study the effect of freezing and different thawing methods on the moisture, fat an fatty acid content of fried sardines, fresh sardine fillets were first frozen and then some were thawed either in a refrigerator at 4°C or in a microwave over prior to frying. These fillets were then analyzed both before and after being fried in olive oil. Frying increased the fat content of the fillets, mainly due to water losses, especially in those thawed in the refrigerator. Mono-unsaturated fatty acid (MUFA content increased in fresh and frozen fillets after frying from 21% to 55% and 56%, respectively. However, thawing prior to frying had a different effect depending on the method because oleic acid absorption was facilitated by refrigerator-thawing, the MUFA content increased to 61,8%, whereas after microwave-thawing the MUFA content reached 47%. Saturated and polyunsaturated fatty acids decreased in fried fillets compared to uncooked ones as a consequence of the increase in MUFA. Frying decreased the C22:6/C16:0 ratio with respect to fresh fillets in frozen fillets and in those thawed in the refrigerator but not in those thawed in a microwave.

    Filetes de sardinas frescas, congeladas y descongeladas en frigorífico a 4°C o en microondas se analizaron en crudo y después de freírlos en aceite de oliva, con objeto de conocer si la congelación y descongelación, previa a la fritura, alteraba los cambios en humedad, grasa y composición en ácidos grasos que introdujera la fritura. El contenido graso (g/100g de filetes de sardinas se incrementó durante el proceso de fritura, debido, sobre todo, a las pérdidas de agua. Dicho efecto aumentó principalmente en la descongelación en frigorífico. Con la fritura, la sardina fresca y la congelada sin previa descongelación se enriquecieron en ácido oleico, ascendiendo el contenido de ácidos grasos monoinsaturados en (AGM del 21 al 55-56%. La descongelación, anterior a la fritura, influyó de forma

  8. anchovy Engraulis capensis, sardine Sardinops sa

    African Journals Online (AJOL)

    spamer

    rates ranged between 0.05 and 0.29.h-1, with mean values of 0.09 and 0.27.h-1 for fish fed zooplankton and phytoplankton ... Linear, square root, and exponential func- tions were ...... Far Eastern sardine and their implication in the fluctuation.

  9. Bases conceptuales para la aplicación de una evaluación de estrategias de manejo (EEM en sardina común (Strangomera bentincki y anchoveta (Engraulis ringens en la zona centro-sur de Chile

    Directory of Open Access Journals (Sweden)

    Marcos Arteaga

    2014-07-01

    Full Text Available Se identifican los factores claves a considerar en el desarrollo de una evaluación de estrategias de manejo (EEM para los recursos pequeños pelágicos en la zona de centro-sur de Chile, sardina común (Strangomera bentincki y anchoveta (Engraulis ringens. En Chile, la EEM no ha sido aplicada al manejo de estas pesquerías y la asesoría científica se ha desarrollado sobre la evaluación de estrategias de explotación utilizando modelos de evaluación mono-específicos. Para ambas especies se analizan los siguientes tópicos: i alternancia en la abundancia poblacional asociada a los pulsos de reclutamientos y capturas, ii variabilidad temporal en la fuerza del reclutamiento, iii estacionalidad del crecimiento cohorte y especie-específico, y iv relación ambiente-recurso. Los resultados evidencian que los tópicos analizados debieran ser considerados en la construcción de un modelo operativo y/o en la regla de cosecha, dado el carácter mixto de ambas pesquerías, su marcada alternancia y la influencia de las condiciones ambientales. Por lo tanto, se propone que el diseño e implementación de una EEM para sardina común y anchoveta, incluya los elementos señalados en un marco de evaluación multi-especifico y de manejo de carácter mixto.

  10. Trends in spatio-temporal distribution of Peruvian anchovy and other small pelagic fish biomass from 1966-2009 Tendencias espacio-temporales en la distribución de la biomasa de anchoveta peruana y de otros peces pelágicos pequenos entre 1966 y 2009

    Directory of Open Access Journals (Sweden)

    Mariano Gutiérrez

    2012-09-01

    de pequenos peces pelágicos de la región norte del Sistema de la Corriente de Humboldt (NHCS son el producto de la variación de forzantes ambientales en diferentes escalas de tiempo y espacio que influyen entre el ecosistema 'frío' costero y el oceánico 'cálido'. La información para estudiar estas fluctuaciones provienen mayormente de las pesquerías, y muestran que la anchoveta (Engraulis ringens incrementa su abundancia cuando la de sardina (Sardinops sagax declina y viceversa. Sin embargo, utilizando datos acústicos de biomasa latitudinal se muestra que otras especies como la caballa (Scomber japonicus y el jurel (Trachurus murphyi también siguen la misma tendencia opuesta a anchoveta, lo que en principio indica que los datos pesqueros disponibles no indican la verdadera dimensión del balance de abundancia entre especies. Utilizando diagramas de Hovmoller se analizan los cambios en la biomasa acústica latitudinal, capturas e influencia de eventos El Nino ocurridos entre 1966 y 2009 con el objetivo de describir: 1 cómo el patrón de distribución decadal de anchoveta se movió de sur a norte desde la década de 1960, 2 cómo se han producido cambios concomitantes en la abundancia latitudinal de otras especies tales como sardina, caballa y jurel antes, durante y después de eventos El Nino, y 3 cuál fue el efecto general de la sucesión de eventos El Nino sobre todas estas especies. Se concluye que: a cada evento El Nino ha tenido un efecto en la expansión o contracción de la distribución de especies pelágicas, con diferente gradiente latitudinal, y b El Nino 1997-98 no disparó sino aceleró la fase declinante de la abundancia de sardina, caballa y jurel al reducirse el tamano de su hábitat ideal debido a una expansión del hábitat costero que presentó además un acercamiento a la superficie del límite superior de la Zona Mínima de Oxígeno (MOZ. Las observaciones logradas con datos acústicos podrían ser tomadas en consideración para el

  11. Preservación y abundancia de escamas de peces en sedimentos del margen continental de Chile (21-36° S Fish scale preservation and abundance in sediments from the continental margin off Chile (21-36° S

    Directory of Open Access Journals (Sweden)

    JAVIER A DÍAZ-OCHOA

    2008-12-01

    Full Text Available Con el objetivo de evaluar la relación entre la preservación de escamas de peces y las variaciones en las condiciones redox en sedimentos del margen continental de Chile, este trabajo presenta recuentos de escamas de peces y concentraciones normalizadas de elementos redox sensibles (Mo/Al, S/Al, Fe/Al en ocho testigos de sedimento recolectados en la zona de minimo oxígeno frente a Chile (Iquique: 20°15' S, bahía de Mejillones: 23° S y Concepción: 36° S. En el norte de Chile (Iquique y Mejillones predominan las escamas de anchoveta (Engraulis ringens y de peces de la familia Myctophidae (media = 90 y 120 escamas 1.000 cm-3, respectivamente mientras que en Chile centro-sur (Concepción son más abundantes las escamas de jurel (Trachurus murphy; media = 140 escamas 1.000 cm-3. La abundancia de escamas de merluza común (Merluccius gayi gayi y de sardina (Sardinops sagax es aproximadamente un orden de magnitud más baja que la de anchoveta o jurel. En general, los valores más altos y los rangos más amplios de variación en las razones Mo/Al, S/Al y Fe/Al se encuentran en Mejillones (Mo/Al ~0,8-12 mg g-1, S/Al 0,2-4,6 g g-1, Fe/Al 0,3-0,7 g g-1 seguidos por Iquique (Mo/Al -0,2-1,8; S/Al 0,2-0,7, Fe/Al 0,5-0,8, mientras que Concepción revela valores más bajos y poco variables (Mo/Al ~0,07, S/Al ~0,15 y Fe/Al ~0,5. La razón Mo/Al, utilizada como indicador de paleo-oxigenación, permite inferir condiciones reductoras relativamente más intensas en los sedimentos de la Bahía de Mejillones e Iquique que en Concepción. En las tres localidades de muestreo se evidencia una asociación estadísticamente significativa entre la abundancia de escamas de anchoveta y el logaritmo de la razón Mo/Al (r²= 0,46; P 1 mg g-1.The relationship between fish scale preservation and variations in the sediment redox conditions on Chile's continental shelf are evaluated herein through fish scale counts and normalized concentrations of redox sensitive elements

  12. Clasificación acústica de anchoveta (Engraulis ringens y sardina común (Strangomera bentincki mediante máquinas de vectores soporte en la zona centro-sur de Chile: efecto de la calibración de los parámetros en la matriz de confusión Acoustic classification of anchovy (Engraulis ringens and sardine (Strangomera bentincki using support vector machines in central-southern Chile: effect of parameter calibration on the confusion matrix

    Directory of Open Access Journals (Sweden)

    Hugo Robotham

    2012-03-01

    Full Text Available Se clasificó la anchoveta (Engraulis ringens y sardina común (Strangomera bentincki detectadas mediante equipos acústicos en la zona centro-sur de Chile, mediante el método de Máquinas de Vectores Soporte (SVM. Para esto se utilizaron descriptores de cardúmenes extraídos desde ecogramas, que fueron clasificados como morfológicos, batimétricos, energéticos y posicional espacial. Para lograr clasificaciones precisas mediante la utilización de esta metodología, fue necesario optimizar parámetros correspondientes al Kernel-Gaussiano, γ y de penalización del modelo C, mediante el análisis del efecto de la calibración sobre las matrices de confusión resultantes de la clasificación de las especies analizadas. El método SVM ajustó correctamente el 95,3% de los cardúmenes de anchoveta y sardina común. Los parámetros óptimos del Kernel-Gaussiano γ y de penalización C obtenidos mediante la metodología propuesta fueron γ = 450 y C = 0,95, respectivamente. Los parámetros mencionados incidieron de manera importante en la matriz de confusión y los porcentajes de clasificación final, por lo que se sugiere establecer, en aplicaciones futuras de este método, un protocolo experimental de calibración. La sardina común fue la especie con menor error de clasificación en el conjunto de las matrices de confusión. El descriptor correspondiente a profundidad del fondo fue el más sensible al SVM, la segunda variable en importancia es el descriptor distancia a la costa.The support vector machines (SVM method was used to classify the anchovy (Engraulis ringens and common sardine (Strangomera bentincki species detected in south-central Chile by means of acoustic equipment. For this, descriptors of fish schools (morphology, bathymetry, energy, spatial position extracted from ecograms were used. In order to obtain precise classifications using this methodology, it was necessary to optimize the parameters Gaussian-Kernel γ and penalty term

  13. A fuzzy-logic tool for multi-criteria decision making in fisheries: the case of the South African pelagic fishery

    DEFF Research Database (Denmark)

    Paterson, B.; Jarre, Astrid; Moloney, C.L.

    2007-01-01

    The present study presents an electronic decision-support tool that uses a fuzzy-logic model of expert knowledge to assist in multi-criteria decision-making in the context of an Ecosystem Approach to Fisheries (EAF). The prototype model integrates the multiple goals and objectives related...... to the evaluation of the ecosystem performance of the South African sardine Sardinops sagax fishery into a NetWeaver knowledge base and provides intuitive visual outputs to communicate results to managers and stakeholders. The software tool was developed in a consultative process with key experts and follows...... on expert opinion. Results show that the model is robust and conservative. The strength of the approach lies in the ability to include variables that are difficult to measure. It provides a means of rendering value judgements explicit and transparent. The tool synthesises a large amount of information...

  14. Phenological and distributional shifts in ichthyoplankton associated with recent warming in the northeast Pacific Ocean.

    Science.gov (United States)

    Auth, Toby D; Daly, Elizabeth A; Brodeur, Richard D; Fisher, Jennifer L

    2018-01-01

    Understanding changes in the migratory and reproductive phenology of fish stocks in relation to climate change is critical for accurate ecosystem-based fisheries management. Relocation and changes in timing of reproduction can have dramatic effects upon the success of fish populations and throughout the food web. During anomalously warm conditions (1-4°C above normal) in the northeast Pacific Ocean during 2015-2016, we documented shifts in timing and spawning location of several pelagic fish stocks based on larval fish samples. Total larval concentrations in the northern California Current (NCC) during winter (January-March) 2015 and 2016 were the highest observed since annual collections first occurred in 1998, primarily due to increased abundances of Engraulis mordax (northern anchovy) and Sardinops sagax (Pacific sardine) larvae, which are normally summer spawning species in this region. Sardinops sagax and Merluccius productus (Pacific hake) exhibited an unprecedented early and northward spawning expansion during 2015-16. In addition, spawning duration was greatly increased for E. mordax, as the presence of larvae was observed throughout the majority of 2015-16, indicating prolonged and nearly continuous spawning of adults throughout the warm period. Larvae from all three of these species have never before been collected in the NCC as early in the year. In addition, other southern species were collected in the NCC during this period. This suggests that the spawning phenology and distribution of several ecologically and commercially important fish species dramatically and rapidly changed in response to the warming conditions occurring in 2014-2016, and could be an indication of future conditions under projected climate change. Changes in spawning timing and poleward migration of fish populations due to warmer ocean conditions or global climate change will negatively impact areas that were historically dependent on these fish, and change the food web structure

  15. Análisis del crecimiento larvario en anchoa ("Engraulis encrasicolus") y sardina ("Sardina pilchardus") del Mediterráneo occidental

    OpenAIRE

    Quintanilla Hervás, José María

    2016-01-01

    Los primeros estadios de las especies de pequeños pelágicos forman parte del ictioplancton, que representa la fracción zooplanctónica compuesta por los huevos y larvas de peces (Ahlstrom & Moser 1976). Las fases larvarias de estas especies se extienden desde la eclosión de larva del huevo hasta que alcanza el estado juvenil cuando la larva adquiere el aspecto de un pequeño adulto (Blaxter 1969). Teniendo en cuenta todo su ciclo vital, durante sus fases larvarias las especies se ven sometidas ...

  16. Proteolysis of Sardine (Sardina pilchardus and Anchovy (Stolephorus commersonii by Commercial Enzymes in Saline Solutions

    Directory of Open Access Journals (Sweden)

    Chau Minh Le

    2015-01-01

    Full Text Available Fish sauce production is a very long process and there is a great interest in shortening it. Among the different strategies to speed up this process, the addition of external proteases could be a solution. This study focuses on the eff ect of two commercial enzymes (Protamex and Protex 51FP on the proteolysis of two fish species traditionally converted into fish sauce: sardine and anchovy, by comparison with classical autolysis. Hydrolysis reactions were conducted with fresh fish at a temperature of 30 °C and under different saline conditions (from 0 to 30 % NaCl. Hydrolysis degree and liquefaction of the raw material were used to follow the process. As expected, the proteolysis decreased with increasing amount of salt. Regarding the fi sh species, higher rate of liquefaction and higher hydrolysis degree were obtained with anchovy. Between the two proteases, Protex 51FP gave better results with both fi sh types. This study demonstrates that the addition of commercial proteases could be helpful for the liquefaction of fi sh and cleavage of peptide bonds that occur during fi sh sauce production and thus speed up the production process.

  17. Effect of natural antioxidants on the quality of frozen sardine fillets (Sardina pilchardus

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    Rui Manuel Maneta Ganhão

    2014-06-01

    Full Text Available The use of new technologies / processes provides different benefits on seafood sector, namely by enhanced the shelf-life of fish products with high polyunsaturated fatty acid composition. This is particularly critical during some months of the year when fish (e.g. sardines are larger supply than demand by consumers. The aim of this study was to performed the optimization process of adding natural antioxidants on frozen sardine fillets and evaluated the effect of addition of two natural antioxidants on the lipid oxidation process during storage at -200C. To evaluate the effect of the addition of antioxidants in sardine fillets, the product matrix was chemical characterized, including by the evaluation of the fatty acid profile. The lipid oxidation process was followed by the primary products (peroxide value and secondary products (TBARS quantification, and also by the analysis of the sensory changes (instrumental assessment of color. Finally, it was done a hedonic preference test to know the opinion of consumers about the frozen fillets with and without antioxidant. The natural antioxidants used, tocopherol (54 mg/fillet and tocopherols (15 mg/fillet with rosemary extract (6.5 mg/fillet inhibited or retarded the oxidation over time of storage when compared with the control samples, that had advanced oxidation process. There was not statistically differences among the fillets treated with tocopherol in the presence and absence of rosemary extract. However, our laboratorial results shown slight tendency for the view that the antioxidant tocopherols and rosemary extract had a greater effect on the oxidative stability of fillets. This observation is in line with results of the hedonic test consumer preference. The use of natural antioxidants is an inexpensive solution which allows the complete use of products with less waste of fish products and with a great need for disposal. At the same time meets the consumer´s requirements.

  18. Feeding of European pilchard (Sardina pilchardus in the northwestern Mediterranean: from late larvae to adults

    Directory of Open Access Journals (Sweden)

    David Costalago

    2014-03-01

    Full Text Available We assessed the relative importance of different prey types of the European pilchard (European sardine from the late larval to the adult stage. Two different methodologies for analysing stomach contents were used to describe the trophic dynamics of sardine and the relationship of sardine feeding behaviour with the ontogenetic development of body structures used for feeding, such as gill rakers and pyloric caeca. This information is essential to accurately depict the use of the planktonic resources in the area by sardine and to discuss the extent to which the sardine population could be affected by environmental changes in the Mediterranean Sea. We showed that cladocerans in summer and diatoms in winter were numerically the most important prey types for both juveniles and adults. However, decapod larvae were the most important prey during all seasons in terms of carbon content. Accordingly, differences in methodology should be considered in the analysis of sardine diets. An analysis of the composition of the plankton showed that small copepods were strongly selected by sardines at all ages and in both seasons. We also observed that the pyloric caeca began to grow when the sardines were approximately 4-5 cm standard length (SL and ended their development when the sardines reached approximately 8 cm SL, whereas the gill rakers appeared to be completely functional when the sardines reached 7 cm SL. Therefore, filter feeding of small particles could be performed with total efficacy beginning at 7-8 cm SL. In view of the energetic advantage of filter feeding in a well-adapted filter-feeding species such as sardine, the prospective limited availability of small particles hypothesized by certain authors for the Mediterranean could have negative consequences for sardine. This study demonstrates that sardine populations, given their extremely high dependence on the lower marine trophic levels, could be strongly affected by alterations in the environment and in the planktonic community.

  19. An Empty Donut Hole: the Great Collapse of a North American Fishery

    Directory of Open Access Journals (Sweden)

    Kevin M. Bailey

    2011-06-01

    Full Text Available Walleye pollock (Theragra chalcogramma is North America's most abundant and lucrative natural fishery, and is the world's largest fishery for human food. The little-known demise of the "Donut Hole" stock of pollock in the Aleutian Basin of the central Bering Sea during the 1980s is the most spectacular fishery collapse in North American history, dwarfing the famous crashes of the northern cod and Pacific sardine (Sardinops sagax. This collapse has received scant recognition and became evident only in 1993 when fishing was banned by an international moratorium; nearly 20 years later it has not recovered. The history of fishing in the North Pacific Ocean after World War II offers some insights into how the Donut Hole pollock fishery developed, and the societal and economic pressures behind it that so influenced the stock's fate. Overfishing was, without a doubt, the greatest contributor to the collapse of the Aleutian Basin pollock fishery, but a lack of knowledge about population biocomplexity added to the confusion of how to best manage the harvest. Unfortunately, the big scientific questions regarding the relationship of Donut Hole fish to other stocks are still unanswered.

  20. A WELL PRESERVED SKELETON OF THE FOSSIL SHARK COSMOPOLITODUS HASTALIS FROM THE LATE MIOCENE OF PERU, FEATURING FISH REMAINS AS FOSSILIZED STOMACH CONTENTS

    Directory of Open Access Journals (Sweden)

    ALBERTO COLLARETA

    2017-01-01

    Full Text Available Both the preservation of the poorly mineralized skeleton of sharks and the preservation of stomach contents are rarely observed in the fossil record. Here we report on a partial skeleton of a lamniform shark, including portions of the visceral arches and the anterior segment of the vertebral column, collected from the late Miocene beds of the Pisco Formation exposed at Cerro Yesera (Ica Desert, South Peru. Based on the morphology of the preserved teeth, this specimen was determined as a juvenile of the extinct lamnid species Cosmopolitodus hastalis. The shark skeleton includes remains of fish (featuring a pilchard determined as Sardinops sp. cf. S. sagax in the abdominal region. These fish remains are interpreted herein as the fossilized stomach contents of the shark. For the first time, piscivory is demonstrated in a juvenile individual of Cosmopolitodus hastalis. This result is consistent with the current knowledge about the feeding habits of immature individuals of extant lamniform shark species (including Carcharodon carcharias and Isurus oxyrinchus. Our report further outlines the fundamental role of schooling pilchards in the late Miocene trophic chains of the highly productive coastal waters off present South Peru. Moreover, the find of this well preserved shark skeleton strengthens the qualification of the Pisco Formation as a Fossil-Lagerstätte, and emphasizes the role of early mineralization processes in cases of exceptional preservation.

  1. Macro-Scale Patterns in Upwelling/Downwelling Activity at North American West Coast.

    Directory of Open Access Journals (Sweden)

    Romeo Saldívar-Lucio

    Full Text Available The seasonal and interannual variability of vertical transport (upwelling/downwelling has been relatively well studied, mainly for the California Current System, including low-frequency changes and latitudinal heterogeneity. The aim of this work was to identify potentially predictable patterns in upwelling/downwelling activity along the North American west coast and discuss their plausible mechanisms. To this purpose we applied the min/max Autocorrelation Factor technique and time series analysis. We found that spatial co-variation of seawater vertical movements present three dominant low-frequency signals in the range of 33, 19 and 11 years, resembling periodicities of: atmospheric circulation, nodal moon tides and solar activity. Those periodicities might be related to the variability of vertical transport through their influence on dominant wind patterns, the position/intensity of pressure centers and the strength of atmospheric circulation cells (wind stress. The low-frequency signals identified in upwelling/downwelling are coherent with temporal patterns previously reported at the study region: sea surface temperature along the Pacific coast of North America, catch fluctuations of anchovy Engraulis mordax and sardine Sardinops sagax, the Pacific Decadal Oscillation, changes in abundance and distribution of salmon populations, and variations in the position and intensity of the Aleutian low. Since the vertical transport is an oceanographic process with strong biological relevance, the recognition of their spatio-temporal patterns might allow for some reasonable forecasting capacity, potentially useful for marine resources management of the region.

  2. Metals and metalloids in Little Penguin (Eudyptula minor) prey, blood and faeces.

    Science.gov (United States)

    Finger, Annett; Lavers, Jennifer L; Dann, Peter; Kowalczyk, Nicole D; Scarpaci, Carol; Nugegoda, Dayanthi; Orbell, John D

    2017-04-01

    Piscivorous species like the Little Penguin (Eudyptula minor) are particularly at risk of being negatively impacted by pollution due to their heightened exposure through aquatic food chains. Therefore, determining the concentration of heavy metals in the fish prey of seabirds is an essential component of assessing such risk. In this study, we report on arsenic, cadmium, mercury, lead and selenium concentrations in three fish species, which are known to comprise a substantial part of the diet of Little Penguins at the urban colony of St Kilda, Melbourne, Australia. Metal concentrations in the fish sampled were generally within the expected limits, however, arsenic and mercury were higher than reported elsewhere. Anchovy (Engraulis australis) and sandy sprat (Hyperlophus vittatus) contained higher Hg concentrations than pilchard (Sardinops sagax), while sandy sprat and pilchard contained more selenium. We present these findings together with metal concentrations in Little Penguin blood and faeces, sampled within weeks of the fish collection. Mercury concentrations were highest in the blood, while faeces and fish prey species contained similar concentrations of arsenic and lead, suggesting faeces as a primary route of detoxification for these elements. We also investigated paired blood - faecal samples and found a correlation for selenium only. Preliminary data from stable isotope ratios in penguin blood indicate that changes in penguin blood mercury concentrations cannot be explained by trophic changes in their diet alone, suggesting a variation of bioavailable Hg within this semi-enclosed bay. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Larval fish variability in response to oceanographic features in a nearshore nursery area.

    Science.gov (United States)

    Pattrick, P; Strydom, N A

    2014-09-01

    The influence of oceanographic features on ichthyoplankton assemblages in the warm temperate nearshore region of Algoa Bay, South Africa, was assessed. The nearshore ichthyoplankton comprised 88 taxa from 34 families. Samples were collected at six stations between August 2010 and July 2012 using a plankton ring net of 750 mm diameter and 500 µm mesh aperture. The majority of larvae collected were in a preflexion stage, indicating the potential importance of the nearshore for newly hatched larvae. Engraulidae dominated the catch (38·4%), followed by Cynoglossidae (28·1%) and Sparidae (8·4%). Larval fish abundance was highest during austral spring and summer (September to February). Unique patterns in responses of each dominant fish species to oceanographic features in the nearshore indicate the sensitivity of the early developmental stage to environmental variables. Using generalized linear models, ichthyoplankton abundance responded positively to upwelling and when warm water plumes originating from an Agulhas Current meander entered Algoa Bay. Highest abundances of Engraulis encrasicolus and Sardinops sagax were observed during Agulhas Plume intrusions into Algoa Bay. When a mixed and stratified water column persisted in the nearshore region of Algoa Bay, larval fish abundance decreased. The nearshore region of Algoa Bay appears to serve as a favourable environment for the accumulation of ichthyoplankton. © 2014 The Fisheries Society of the British Isles.

  4. Characteristic ichthyoplankton taxa in the separation zone of the East Australian Current: Larval assemblages as tracers of coastal mixing

    Science.gov (United States)

    Syahailatua, Augy; Roughan, Moninya; Suthers, Iain M.

    2011-03-01

    Ichthyoplankton assemblages were compared between regions dominated by the oligotrophic East Australian Current (EAC) and the inner-shelf waters off southeastern Australia, to determine if the early life history of fish was related to the separation of the EAC from the coast, producing different water masses as well as characteristic taxa. Samples were collected at the surface and in sub-surface waters, at 50 and 100 m isobath stations, during two summer research voyages in November 1998 and January 1999. On both voyages the study region was characterized by coastal and EAC waters in the north (˜31°S), and in the south by topographically induced upwelling (˜31°S), associated with narrowing of the continental shelf and separation of the EAC from the coast. Among the 111 families of larval fish, we observed distinctive assemblages of ichthyoplankton associated with the two different water masses. A greater abundance of the Carangidae, Labridae, Lutjanidae, Microcanthidae, Myctophidae and Scombridae was associated with the nutrient poor EAC water mass, while the Callionymidae, Clupeidae, Platycephalidae and Sillaginidae were mostly found in the cooler and/or fresher inner-shelf water mass. We assessed these patterns with opportunistic samples from an unusual, wind-driven upwelling event in the north (˜31°S) earlier in the November voyage. The relative abundance of these 10 characteristic families distinguished this wind-driven upwelling event from the subsequent relaxation and predominance of the EAC assemblage at this location just 6 d later. Distinctive and abundant families such as larval clupeids, relative to larval carangids, could be a useful marker of inner-shelf, EAC and mixed water masses in the absence of robust hydrographic data. This and related studies indicate contrast in early life histories of Sardinops sagax and Trachurus spp., which appear to spawn respectively in the inner-shelf and outer-shelf waters. The post-flexion stages of S. sagax

  5. New insights into the early life ecology of Sardina pilchardus (Walbaum, 1792 in the northern Iberian Atlantic

    Directory of Open Access Journals (Sweden)

    Sandra Ramos

    2009-09-01

    Full Text Available In the Atlantic Iberian estuaries, sardines tend to be a minor component of the ichthyoplankton assemblages, with rare occurrence largely restricted to estuarine mouths. However, this was not the case of the Lima estuary (NW Portugal, where sardines were the most abundant and frequently occurring marine taxon of the larval fish assemblages. Abundance of sardines collected during a two-year survey (2002-2004 ranged from 0.5 to 60.8 larvae/100 m3, with the majority still showing yolk and unpigmented eyes. Moreover, 80% of sardines were 8 days old or less and the total length ranged from 2 to 16 mm. Seasonal variations of sardine occurrence in the Lima estuary correlated with temporal variations of salinity and temperature in the water column. The unusually high river-flow observed during the winter of 2002-2003, which preceded the spring-summer abundance peak, seemed to act as a signal for the estuarine recruitment that was encountered. In addition, the estuarine occurrence of sardine larvae was also correlated with the intensity of summer upwelling, which was responsible for coastal depletion of sardine larvae resulting in estuarine low catches during the summer of 2002. The Lima estuary also revealed another peculiarity related to the lack of temporal synchrony between coastal spawning activity and occurrence of larvae within the estuary. The abundance peaks of newly-hatched larvae (autumn 2002 and spring-summer 2003 did not coincide with the winter-spring spawning pattern described earlier for the northern Iberian coast. Modifications of the spawning strategy of the northern Iberian sardine stock are discussed based on these new insights into the early life of S. pilchardus.

  6. Quantifying mercury isotope dynamics in captive Pacific bluefin tuna (Thunnus orientalis

    Directory of Open Access Journals (Sweden)

    Sae Yun Kwon

    2016-02-01

    Full Text Available Abstract Analyses of mercury (Hg isotope ratios in fish tissues are used increasingly to infer sources and biogeochemical processes of Hg in natural aquatic ecosystems. Controlled experiments that can couple internal Hg isotope behavior with traditional isotope tracers (δ13C, δ15N can improve the applicability of Hg isotopes as natural ecological tracers. In this study, we investigated changes in Hg isotope ratios (δ202Hg, Δ199Hg during bioaccumulation of natural diets in the pelagic Pacific bluefin tuna (Thunnus orientalis; PBFT. Juvenile PBFT were fed a mixture of natural prey and a dietary supplement (60% Loligo opalescens, 31% Sardinops sagax, 9% gel supplement in captivity for 2914 days, and white muscle tissues were analyzed for Hg isotope ratios and compared to time in captivity and internal turnover of δ13C and δ15N. PBFT muscle tissues equilibrated to Hg isotope ratios of the dietary mixture within ∼700 days, after which we observed a cessation in further shifts in Δ199Hg, and small but significant negative δ202Hg shifts from the dietary mixture. The internal behavior of Δ199Hg is consistent with previous fish studies, which showed an absence of Δ199Hg fractionation during Hg bioaccumulation. The negative δ202Hg shifts can be attributed to either preferential excretion of Hg with higher δ202Hg values or individual variability in captive PBFT feeding preferences and/or consumption rates. The overall internal behavior of Hg isotopes is similar to that described for δ13C and δ15N, though observed Hg turnover was slower compared to carbon and nitrogen. This improved understanding of internal dynamics of Hg isotopes in relation to δ13C and δ15N enhances the applicability of Hg isotope ratios in fish tissues for tracing Hg sources in natural ecosystems.

  7. Managing small-scale commercial fisheries for adaptive capacity: insights from dynamic social-ecological drivers of change in Monterey Bay.

    Science.gov (United States)

    Aguilera, Stacy E; Cole, Jennifer; Finkbeiner, Elena M; Le Cornu, Elodie; Ban, Natalie C; Carr, Mark H; Cinner, Joshua E; Crowder, Larry B; Gelcich, Stefan; Hicks, Christina C; Kittinger, John N; Martone, Rebecca; Malone, Daniel; Pomeroy, Carrie; Starr, Richard M; Seram, Sanah; Zuercher, Rachel; Broad, Kenneth

    2015-01-01

    Globally, small-scale fisheries are influenced by dynamic climate, governance, and market drivers, which present social and ecological challenges and opportunities. It is difficult to manage fisheries adaptively for fluctuating drivers, except to allow participants to shift effort among multiple fisheries. Adapting to changing conditions allows small-scale fishery participants to survive economic and environmental disturbances and benefit from optimal conditions. This study explores the relative influence of large-scale drivers on shifts in effort and outcomes among three closely linked fisheries in Monterey Bay since the Magnuson-Stevens Fisheries Conservation and Management Act of 1976. In this region, Pacific sardine (Sardinops sagax), northern anchovy (Engraulis mordax), and market squid (Loligo opalescens) fisheries comprise a tightly linked system where shifting focus among fisheries is a key element to adaptive capacity and reduced social and ecological vulnerability. Using a cluster analysis of landings, we identify four modes from 1974 to 2012 that are dominated (i.e., a given species accounting for the plurality of landings) by squid, sardine, anchovy, or lack any dominance, and seven points of transition among these periods. This approach enables us to determine which drivers are associated with each mode and each transition. Overall, we show that market and climate drivers are predominantly attributed to dominance transitions. Model selection of external drivers indicates that governance phases, reflected as perceived abundance, dictate long-term outcomes. Our findings suggest that globally, small-scale fishery managers should consider enabling shifts in effort among fisheries and retaining existing flexibility, as adaptive capacity is a critical determinant for social and ecological resilience.

  8. Immunological cross-reactivity between four distant parvalbumins-Impact on allergen detection and diagnostics.

    Science.gov (United States)

    Sharp, Michael F; Stephen, Juan N; Kraft, Lukas; Weiss, Thomas; Kamath, Sandip D; Lopata, Andreas L

    2015-02-01

    Fish are the largest and most diverse group of vertebrates. Fish are also a part of the eight food groups that cause the majority of IgE mediated food reactions. Detection tools for fish allergens are however limited due to the great diversity of fish species, despite fish allergy and its major allergen parvalbumin being well documented. The most commonly studied fish are frequently consumed in North America and Europe. However, much less is known about fish allergens in the Australasian region although fish is widely consumed in this region. A comprehensive phylogenetic analysis was performed of known parvalbumin amino acid sequences to determine possible candidate antigens for new cross-reactive antibodies to be used to detect most fish parvalbumins. Polyclonal rabbit antibodies were raised against parvalbumins from frequently consumed barramundi (Lates calcarifer), basa (Pangasius bocourti), pilchard (Sardinops sagax) and Atlantic salmon (Salmo salar). These were evaluated for cross-reactivity against a panel of 45 fish extracts (raw, heated and canned fish). Anti-barramundi parvalbumin proved to be the most cross-reactive antibody, detecting 87.5% of the 40 species analyzed, followed by anti-pilchard and anti-basa antibody. In contrast the anti-salmon antibody was very specific and only reacted to salmonidae and a few other fish. All analyzed fish species, except mahi mahi, swordfish, yellowfin tuna and all 5 canned fish had parvalbumin detected in raw extracts. However antibody reactivity to many fish was heat liable or susceptible to denaturation, demonstrating that some parvalbumins have most likely conformational epitopes, which lose antibody reactivity after heat treatment. We have demonstrated the generation of highly cross-reactive anti-parvalbumin antibodies that could be used for the detection of allergenic fish parvalbumin in contaminated food products. This cross-reactivity study thus shows processing of fish, especially canning, can have on impact

  9. Long-term variation in a central California pelagic forage assemblage

    Science.gov (United States)

    Ralston, Stephen; Field, John C.; Sakuma, Keith M.

    2015-06-01

    A continuous 23 year midwater trawl survey (1990-2012) of the epipelagic forage assemblage off the coast of central California (lat. 36°30‧-38°20‧ N) is described and analyzed. Twenty taxa occurred in ≥ 10% of the 2037 trawls that were completed at 40 distinct station locations. The dominant taxa sampled by the 9.5 mm mesh net included a suite of young-of-the-year (YOY) groundfish, including rockfish (Sebastes spp.) and Pacific hake (Merluccius productus), two clupeoids (Engraulis mordax and Sardinops sagax), krill (Euphausiacea), cephalopods (Doryteuthis opalescens and Octopus sp.), and a variety of mesopelagic species, i.e., Diaphus theta, Tarltonbeania crenularis, "other" lanternfish (Myctophidae), deep-sea smelts (Bathylagidae), and sergestid shrimp. Annual abundance estimates of the 20 taxa were obtained from analysis of variance models, which included year and station as main effects. Principal components analysis of the abundance estimates revealed that 61% of assemblage variance was explained by the first three components. The first component revealed a strong contrast in the abundance of: (a) YOY groundfish, market squid (D. opalescens), and krill with (b) mesopelagics and clupeoids; the second component was associated with long-term trends in abundance. An evaluation of 10 different published oceanographic data sets and CTD data collected during the survey indicated that seawater properties encountered each year were significantly correlated with abundance patterns, as were annual sea-level anomalies obtained from an analysis of AVISO satellite information. A comparison of our findings with several other recent studies of biological communities occurring in the California Current revealed a consistent structuring of forage assemblages, which we conjecture is primarily attributable to large-scale advection patterns in the California Current ecosystem.

  10. Descriptions of digeneans from Sardina pilchardus (Walbaum) (Clupeidae) off the Algerian coast of the western Mediterranean, with a complete list of its helminth parasites

    Czech Academy of Sciences Publication Activity Database

    Marzoug, D.; Boutiba, Z.; Gibson, D. I.; Pérez-del-Olmo, A.; Kostadinova, Aneta

    2012-01-01

    Roč. 81, č. 3 (2012), s. 169-186 ISSN 0165-5752 R&D Projects: GA MŠk LC522; GA ČR GAP505/10/1562 Institutional research plan: CEZ:AV0Z60220518 Keywords : Algeria * FALLAX LACEPEDE * SEA * HEMIURIDAE * ANISAKIDAE * CAUGHT * FISHES * NORTH Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.260, year: 2012

  11. Effect of baking of sardine (Sardina pilchardus) and frying of anchovy (Engraulis encrasicholus) in olive and sunflower oil on their quality.

    Science.gov (United States)

    Zotos, Anastasios; Kotaras, Akylas; Mikras, Emmanouil

    2013-02-01

    Quality changes due to oven-baking of sardine for 20, 40, 50 and 60 min and due to deep frying of anchovy for 2, 3, 4 and 5 min in olive and sunflower oil were studied. Linear increase in total losses with the time of processing was observed. A linear inverse relationship was observed between moisture/lipid and moisture/protein due to time of baking of sardines and time of frying of anchovies (wet matter). However, no changes were detected in sardine samples due to time of baking (dry matter), while a reduction in proteins and ash followed by an increase in lipids was detected in fried anchovies due to time of frying (dry matter). The fatty acid profiles indicated that a rich in EPA + DHA (33.16%) and in ω-3/ω-6 ratio (9.40) baked sardines can be produced in 20 min at 200 °C. The fatty acid profiles of fried anchovies tremendously changed, indicating entirely different products. Olive oil is probably a better medium to fry fish products, since either the two beneficial fatty acids (EPA and DHA) detected at higher concentrations in anchovies fried in olive oil or the ω-3/ω-6 ratio remained at higher values (0.71-2.56). An increase of cholesterol and squalene content with increasing the time of baking was detected in sardine samples, probably due to decline of moisture content. On the contrary, cholesterol significantly reduced due to frying of anchovy in olive oil. Simultaneously squalene concentration significantly and linearly increased, from 3.87 mg/100 g in the unprocessed anchovies to 73.25 mg/100 g in the samples fried for 5 min, indicating its existence at beneficial levels, besides low cholesterol concentration detected in fried olive oil and squalene concentration gradually and linearly decreased, confirming the absorption from the anchovy samples. Similar was the changes of cholesterol and squalene in anchovies samples fried in sunflower oil.

  12. Ingestion of microplastics and natural fibres in Sardina pilchardus (Walbaum, 1792) and Engraulis encrasicolus (Linnaeus, 1758) along the Spanish Mediterranean coast.

    Science.gov (United States)

    Compa, Montserrat; Ventero, Ana; Iglesias, Magdalena; Deudero, Salud

    2018-03-01

    The ingestion of microplastics and natural fibres (microplastics and natural fibres. A latitudinal increase in condition index (Fulton's K) of S. pilchardus gave an indication that larger individuals with better physical condition are less likely to ingest microplastics and natural fibres. Fibres were the most frequent particle type (83%) and Fourier Transform Infrared spectroscopy (FT-IR) analysis indicated polyethylene terephthalate was the most common microplastics material (30%). Results from this study show that both microplastics and natural fibres of anthropogenic origin are common throughout the pelagic environment along the Spanish Mediterranean coast. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Searching for a stock structure in Sardina pilchardus from the Adriatic and Ionian seas using a microsatellite DNA-based approach

    DEFF Research Database (Denmark)

    Ruggeri, Paolo; Splendiani, Andrea; Bonanomi, Sara

    2013-01-01

    of homozygote individuals higher than expected at Hardy-Weinberg equilibrium. The inter-population differentiation level estimated by AMOVA, qST and rRST and Bayesian descriptors detected no signs of population differentiation between the samples analysed. These results are consistent with previous studies...

  14. Searching for a stock structure in Sardina pilchardus from the Adriatic and Ionian seas using a microsatellite DNA-based approach

    Directory of Open Access Journals (Sweden)

    Paolo Ruggeri

    2013-10-01

    Full Text Available In the present study the genetic variability of European sardine from Adriatic and Ionian seas was investigated in order to detect the occurrence of genetic structure within and between these basins. In several samples the analysis of genetic variability at eight microsatellite loci showed a number of homozygote individuals higher than expected at Hardy-Weinberg equilibrium. The inter-population differentiation level estimated by AMOVA, qST and rRST and Bayesian descriptors detected no signs of population differentiation between the samples analysed. These results are consistent with previous studies based on allozymes and several mitochondrial DNA markers and add further evidence contradicting the early identification, based on morphological and reproductive data, of two sub-populations in the Adriatic Sea.

  15. Monitoring programme on toxic metal in bluefish (Pomatomus saltatrix), anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) from Istanbul, Turkey: levels and estimated weekly intake.

    Science.gov (United States)

    Özden, Özkan

    2013-05-01

    Toxic metal (Hg, Cd, Pb, Cu and Zn) concentrations of small-medium bluefish, anchovy and sardine in Istanbul, Turkey, were determined using inductively coupled plasma-mass spectrometry (ICP-MS) throughout 1 year. The concentrations of pollutants were found to vary according to season and species. Estimates of weekly intake levels of the metals were calculated and compared to recommended safe limits for fish consumption by humans. The levels of Cd, Pb, Cu and Zn in the fillets of all species resulted in estimates of weekly intake levels that were lower than the recommended safe limits. The concentrations of Hg of small bluefish in September, of medium bluefish in June and September, of anchovy in March, and of sardine in August and September resulted in estimates of weekly intake levels that were higher than the recommended safe limits for human consumption.

  16. Impact of El Niño events on pelagic fisheries in Peruvian waters

    Science.gov (United States)

    Ñiquen, Miguel; Bouchon, Marilú

    2004-03-01

    Using data from stock assesment surveys on pelagic resources during El Niño events of 1972/73, 1982/83, 1997/98, we analyze biological changes on pelagic ecosystems and pelagic fisheries during different stages of development of El Niño phenomenon: emergence, full, final and post-Niño. Results indicate changes in spatial distribution of resources, their concentration and size structure. In anchovy (Engraulis ringens) a decrease in biomass was observed, which was estimated at 1.2 million tons in September 1998, the lowest throughout the 1990s. This resource showed an asymmetric distribution towards the south of Peru. Other pelagic resources increased their biomass during or after Niño events, primarily sardine (Sardinops sagax), jack mackerel (Trachurus murphyi), pacific mackerel (Scomber japonicus), and longnose anchovy (Anchoa nasus). At the end of the El Niño phenomenon we found less productivity but more diversity in the pelagic ecosystem. During the 1997/98 El Niño, the diversity index (Manual de Ecologia, 1a Edition, Editorial Trillas, Mexico, 267pp) increased from 0.87 to 1.23-1.70. In both the emergence stage and fully developed stages of El Niño we found large numbers of sardine and longnose anchovy present simultaneously. Size structure of sardine, jack mackerel, and pacific mackerel showed an increase in juveniles. Anchovy during El Niño showed a single modal group composed of adults, but the post-Niño phase indicated an increase in juveniles with an average length of 6-7 cm. In El Niño conditions spawning among anchovy was low, but among sardine and pacific mackerel it was high. We observed, for the first time during full spawning, juvenile sardines with a total length of 18-20 cm. The anchovy spawning season during the post-Niño phase was considerably lengthened, from April to December 1998. Drastic change occurred in fisheries when monospecific fisheries, based on anchovy before El Niño, became multispecific fisheries based on sardine, jack

  17. Genetic characterization of the Mascaruna goat, a Sicilian ...

    African Journals Online (AJOL)

    Genetic characterization of the Mascaruna goat, a Sicilian autochthonous population, using molecular markers. Salvatore Mastrangelo, Marco Tolone, Maria Teresa Sardina, Rosalia Di Gerlando, Baldassare Portolano ...

  18. The fate of eggs and larvae of three pelagic species, mackerel (Scomber scombrus, horse mackerel (Trachurus trachurus and sardine (Sardina pilchardus in relation to prevailing currents in the Bay of Biscay: Could they affect larval survival?

    Directory of Open Access Journals (Sweden)

    Paula Alvarez

    2012-05-01

    Full Text Available The spatial distribution of eggs and larvae of three pelagic species, mackerel, horse mackerel and sardine, in the Bay of Biscay was studied in 1998, 2001 and 2004. The spatial distribution was clearly different between the years studied and corresponds quite precisely to different water circulation regimes. Mackerel and horse mackerel larvae are more affected by the prevailing currents than sardine, as their spawning grounds are located offshore, far from the shelf break where the current velocities are higher. Survival rates for mackerel and horse mackerel were higher in 2001, when the offshore larval transport was stronger. However, for sardine, the mortality rate hardly varied between years. The abundance of 25-day-old larvae, considered as an index of the survival rate, appears to be a good recruitment indicator, at least for 1998, 2001 and 2004. Our results did not support the hypothesis of Bakun (1996, which states that dispersion of early life stages towards open ocean waters should cause high larval mortality. At least under the conditions observed for the years studied, the retention of larvae offshore appears to have a positive effect on larval growth and/or survival.

  19. Full-length sequencing and identification of novel polymorphisms in ...

    Indian Academy of Sciences (India)

    Rosalia Di Gerlando

    2017-08-16

    Aug 16, 2017 ... ANNA MARIA SUTERA, MARIA TERESA SARDINA. ∗ ... SNPs that might be important in future studies and laid the basis for further association analyses needed to ..... Haplotype-based analysis can provide higher power,.

  20. RESEARCH ARTICLE Full length sequencing and novel ...

    Indian Academy of Sciences (India)

    Navya

    2016-12-16

    Dec 16, 2016 ... TOLONE, ANNA MARIA SUTERA, MARIA TERESA SARDINA, BALDASSARE ... finding of novel SNPs that might be important in future studies and laid the .... power, precision and quality to assess the relationship between ...

  1. A real-time PCR assay to estimate invertebrate and fish predation on anchovy eggs in the Bay of Biscay

    KAUST Repository

    Albaina, A.; Irigoien, Xabier; Aldalur, Unai; Cotano, Unai; Santos, Marí a; Boyra, Guillermo; Estonba, Andone

    2015-01-01

    In order to investigate the role of predation on eggs and larvae in the recruitment of anchovy (Engraulis encrasicolus), sardine (Sardina pilchardus), sprat (Sprattus sprattus) and 52 macrozooplankton taxa were assayed for anchovy remains in the gut

  2. Maritime Claims Reference Manual.

    Science.gov (United States)

    1997-01-01

    Melenera to Peninsula de Gando From Peninsula de Gando to Moque Arinaga From Moque Arinaga to Punta Tenefe From Punta Tenefe to Playa Maspalomas (E...From Playa Maspalomas (W) to Punta Taozo From Isla de la Aldea to Punta Sardina From Punta Sardina to Punta Ortiz From Punta Ortiz to Punta...to Cabo Ancones 29° 01.10 13° 27.80 From Punta Lima 28° 55.80 13° 36.87 to Punta del Tarjalillo 28° 35.45 13° 49.25 From Punta de la Entallada 28

  3. Biomasa desovante de la anchoveta y condiciones oceanográficas. Crucero 9408- 10 BIC SNP-1 y bolicheras

    OpenAIRE

    Guzmán Cárdenas, Soledad; Ayón Dejo, Patricia; Pizarro Pereyra, Luis

    1995-01-01

    Describe las actividades realizadas en el crucero de evaluación de biomasa desovante de anchoveta y sardina, realizadas desde el 11 de agosto al 4 de octubre de 1994, con el objetivo de evaluar a las poblaciones desovantes de la anchoveta y sardina del litoral, para lo cual exploró el área comprendida entre los 10°00 'S y 17°30 'S, llegando hasta las 102 mm de la costa. Los registros acústicos mostraron que la distribución de la anchoveta fue amplia, desde las 02 hasta las 102 millas de la...

  4. African Journal of Biotechnology - Vol 12, No 24 (2013)

    African Journals Online (AJOL)

    Genetic characterization of the Mascaruna goat, a Sicilian autochthonous population, using molecular markers · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Salvatore Mastrangelo, Marco Tolone, Maria Teresa Sardina, Rosalia Di Gerlando, Baldassare Portolano ...

  5. Chemical composition and antioxidant activity of seven cultivars of guava (Psidium guajava) fruits.

    Science.gov (United States)

    Flores, Gema; Wu, Shi-Biao; Negrin, Adam; Kennelly, Edward J

    2015-03-01

    The antioxidant activity and identification of phenolic compounds of seven edible guava (Psidium guajava) cultivars that varied in colour from white to pink were examined. In the DPPH assay all four pink-pulp guavas (Barbie Pink, Homestead, Sardina 1, Sardina 2) included in the study showed higher activity than the white pulp cultivars (Yen 2 and Sayla) and less than the red pulp guava cultivar (Thai Maroon). In the ABTS(+) assay this trend was the same up to 20 min, but from 20 to 40 min Barbie Pink showed lower activity than the white guavas. Twenty-one compounds were characterised in the cultivars, and ten of them are reported for the first time in this fruit. Principle component analysis was performed to identify differences in chemistry among these cultivars. Our results suggest that the antioxidant activity and phytochemical composition of P. guajava vary significantly according to the cultivar and pulp colour. Copyright © 2014. Published by Elsevier Ltd.

  6. Pelagic fish stock assessment by acoustic methods at Ifremer

    OpenAIRE

    Doray, Mathieu; Masse, Jacques; Petitgas, Pierre; Doray, Mathieu; Masse, Jacques; Petitgas, Pierre

    2010-01-01

    The main objective of Ifremer's pelagic sea surveys (Pelgas in the Bay of Biscay and Pelmed in the Gulf of Lion) is to assess the biomass of anchovy (Engraulis encrasicolus) and sardine (Sardina pilchardus) populations, based on fisheries acoustic data. Complementary data on the whole pelagic ecosystem (hydrology, plankton, fish eggs and larvae, other fish species, seabirds and marine mammals) are also collected during the cruises. This document describes the procedures used to derive stock a...

  7. Achievement and Retention of Spanish Presented Via Videodisc in Linear, Segmented and Interactive Modes.

    Science.gov (United States)

    1987-01-01

    with non-emotional mate- rial . . . . P5. Students who are able to choose from a ’ menu ’ of topics to provide the general con- text of the exercise...smaller version of the videodisc encoded digitally and capable of storing vast numbers of still frames and text files, presents yet another opportunity for...37. En el restaurante , Ramiro pide . a. chorizo y tinto. b. sardinas y vino. c. tortilla y vino. 38. Cuando es t comiendo en el restaurante , Ramiro

  8. CONCENTRACION DE VITAMINA C EN PECES PELAGICOS PEQUEÑOS Y RESPUESTA DE EFECTORES DE INMUNIDAD INNATA Y ANTIOXIDANTE DURANTE LA ESTACION DE DESOVE EN EL AREA DE SURGENCIAS DE CHILE CENTRO-SUR

    OpenAIRE

    KRAUTZ BORQUEZ, MARIA CRISTINA; KRAUTZ BORQUEZ, MARIA CRISTINA

    2011-01-01

    Este estudio abordó la variabilidad en la calidad de alimento, entendida como la composición de macromoléculas y de sustancias esenciales (e.g. vitaminas), y su disponibilidad, en distintos aspectos de la reproducción/fisiología de las poblaciones de peces pelágicos pequeños (Strangomera bentincki, sardina común y Engraulis ringens, anchoveta) endémicos del Sistema de Corrientes de Humboldt. Para ello, se determinó la composición bioquímica (proteínas, aminoácidos libres, lípid...

  9. "El Niño 1997-98": su efecto sobre el ambiente y los recursos pesqueros en el Perú

    Directory of Open Access Journals (Sweden)

    Marco Espino

    2014-06-01

    Full Text Available Se presenta una reseña de los efectos del fenómeno "El Niño 1997-98" en los recursos pesqueros del ecosistema de afloramiento peruano, dando especial énfasis a los cambios en los patrones de distribución y abundancia de los recursos anchoveta, sardina y merluza; ya los cambios en la autoecología de los mismos recursos. Finalmente, se comenta sobre las similitudes y diferencias de los efectos de este fenómeno con otros eventos de la misma naturaleza.

  10. Dinámica poblacional de Opisthonema medirastre (Pisces: Clupeidae en la Costa Pacífica de Costa Rica.

    Directory of Open Access Journals (Sweden)

    Rosa Lidia Soto Rojas

    2016-03-01

    Full Text Available Se analizaron la curva de crecimiento y la talla de la primera madurez  de la sardina Opisthonema medirastre en el Golfo de Nicoya. Los resultados muestran que esta especie presenta una L∞ de 30,6 cm para las hembras y de 28,0 cm para los machos. Los valores de la tasa de crecimiento (K fueron bajos en concordancia con lo esperado para especies de vida corta. La talla de primera madurez de esta especie es de 17,0 cm.

  11. Detection of a diverse marine fish fauna using environmental DNA from seawater samples

    DEFF Research Database (Denmark)

    Thomsen, Philip Francis; Kielgast, Jos; Iversen, Lars Lønsmann

    2012-01-01

    eDNA from 15 different fish species, including both important consumption species, as well as species rarely or never recorded by conventional monitoring. We also detect eDNA from a rare vagrant species in the area; European pilchard (Sardina pilchardus). Additionally, we detect four bird species....... Records in national databases confirmed the occurrence of all detected species. To investigate the efficiency of the eDNA approach, we compared its performance with 9 methods conventionally used in marine fish surveys. Promisingly, eDNA covered the fish diversity better than or equal to any of the applied...

  12. Quimeras. Presentación

    Directory of Open Access Journals (Sweden)

    Julio Premat

    2008-07-01

    Full Text Available Si a una cabeza humana,muy peinada a la moda y muy galana,le añadiera un pintor plumas de galloy un pescuezo de burro o de caballo ;si juntando las piezas desigualesde varios animalespor último en el lienzo retratarauna mujer de lindo talle y caracon alas de avestruz o de gallinay cola de merluza o de sardina,¿quién, amigos Pisones,dejara de reírse a borbotones ?Pues a este lienzo semejante fuera,el poema o quimera,cuyas partes sin tino colocadas,no fuesen a una forma conspiradas [...]Félix...

  13. Efectos del fenómeno "El Niño 1997-98" sobre los principales recursos pelágicos en la costa peruana

    Directory of Open Access Journals (Sweden)

    Miguel Ñiquen

    2014-06-01

    Full Text Available En el período abril 1997 setiembre 1998 fueron realizados 5 cruceros de evaluación de los recursos pelágicos en la costa peruana, éstos permitieron observar cambios en la composición por especies, distribución, estructura por tamaño, reproducción y niveles poblacionales de los principales recursos pelágicos. Estos cambios guardan similitud con los observados en los eventos El Niño 1972-73 y 1982-83, especialmente en cuanto a la disminución de la biomasa de anchoveta y el incremento de otras especies pelágicas. En el período post-Niño se observó cambios notables en la estructura por tallas de anchoveta, mientras que la sardina, samas a y caballa coincidieron en mostrar buenos reclutamientos. La actividad reproductiva también se incrementó, inclusive en tallas juveniles, destacando la incidencia de sardinas sexualmente maduras con longitudes de 18-20 cm, situación que no había sido antes registrada.

  14. Seasonal, lunar and tidal control of ichthyoplankton dynamics at the interface between a temperate estuary and adjacent coastal waters (western Portugal

    Directory of Open Access Journals (Sweden)

    Ana Lígia Primo

    2011-11-01

    Full Text Available Influence of season, lunar-tide cycle and tide on ichthyoplankton at the interface between Mondego estuary and the adjacent coast and on up-estuary transport was evaluated. Seasonal samples were collected at a fixed station at the mouth of the estuary during diel cycles, at neap and spring tides. Additionally, four sampling stations along the estuary were assessed. Pomatoschistus spp. was the main estuarine taxon, while Sardina pilchardus and Parablennius pilicornis were the most important marine species. Ichthyoplankton entrance and transport along the estuary presented a seasonal pattern with higher densities during summer. Lunar-tide cycle also represented an important influence, structuring communities that reach the estuary and their subsequent distribution. Solea senegalensis and Sardina pilchardus seemed to take advantage of spring tides to enter the estuary. S. pilchardus appear to be using tides to move upstream of the estuary. Ichthyoplankton entrance in the estuary seemed related to species spawning period, while its distribution within the estuary depends on in situ spawning and on the capacity of species to counteract currents and river flow. The present study provides a better understanding of ichthyoplankton dynamics at the interface of two coastal systems, reinforcing knowledge of the lunar-tide cycle influence on ichthyoplankton communities.

  15. The relationships between heavy metal (Cd, Cr, Cu, Fe, Pb, Zn) levels and the size of six Mediterranean fish species

    International Nuclear Information System (INIS)

    Canli, Mustafa; Atli, Gueluezar

    2003-01-01

    Significant relationships between metal concentrations and fish size were negative. - Heavy metal (Cd, Cr, Cu, Fe, Pb, Zn) concentrations in the muscle, gill and liver of six fish species (Sparus auratus, Atherina hepsetus, Mugil cephalus, Trigla cuculus, Sardina pilchardus and Scomberesox saurus) from the northeast Mediterranean Sea were measured and the relationships between fish size (length and weight) and metal concentrations in the tissues were investigated by linear regression analysis. Metal concentrations (as μg/g d.w.) were highest in the liver, except for iron in the gill of Scomberesox saurus and lowest in the muscle of all the fish species. Highest concentrations of Cd (4.50), Cr (17.1) and Pb (41.2) were measured in liver tissues of T. cuculus, Sardina pilchardus and A. hepsetus, respectively. The liver of M. cephalus showed strikingly high Cu concentrations (202.8). The gill of Scomberesox saurus was the only tissue that showed highest (885.5) iron concentrations. Results of linear regression analysis showed that, except in a few cases, significant relationships between metal concentrations and fish size were negative. Highly significant (P<0.001) negative relationships were found between fish length and Cr concentrations in the liver of A. hepsetus and M. cephalus, and Cr concentrations in the gill of T. cuculus. Cr and Pb concentrations in the liver and Cu concentrations in all the tissues of Scomberesox saurus also showed very significant (P<0.001) negative relationships. Negative relationships found here were discussed

  16. Testing spatial heterogeneity with stock assessment models

    DEFF Research Database (Denmark)

    Jardim, Ernesto; Eero, Margit; Silva, Alexandra

    2018-01-01

    sub-populations and applied to two case studies, North Sea cod (Gadus morua) and Northeast Atlantic sardine (Sardina pilchardus). Considering that the biological components of a population can be partitioned into discrete spatial units, we extended this idea into a property of additivity of sub......, the better the diffusion process will be detected. On the other hand it showed that weak to moderate diffusion processes are not easy to identify and large differences between sub-populations productivities may be confounded with weak diffusion processes. The application to North Sea cod and Atlantic sardine...... exemplified how much insight can be gained. In both cases the results obtained were sufficiently robust to support the regional analysis....

  17. ESTIMACIÓN DE PARÁMETROS EN MODELOS NO LINEALES: ALGORITMOS Y APLICACIONES

    Directory of Open Access Journals (Sweden)

    Óscar Cornejo Zúñiga

    Full Text Available En este artículo se muestran diferentes algoritmos para estimar parámetros en modelos no lineales. Se aplican primeramente a una base de datos de problemas clasificados difíciles. Posteriormente, se muestra el comportamiento de los algoritmos para el estudio de crecimiento de la merluza común en machos y hembras, anchoveta y sardina común ajustando un modelo de Von Bertalanffy. Se aplica el test de Cerrato para la comparación de crecimientos entre géneros para la merluza común. Los algoritmos se implementaron en ambiente MATLAB presentando un buen comportamiento en cuanto a tiempo CPU, número de iteraciones y exactitud de la solución encontrada respecto de valores certificados de los problemas de la base de datos.

  18. Functional and antioxidant properties of hydrolysates of sardine (S. pilchardus) and horse mackerel (T. mediterraneus) for the microencapsulation of fish oil by spray-drying.

    Science.gov (United States)

    Morales-Medina, R; Tamm, F; Guadix, A M; Guadix, E M; Drusch, S

    2016-03-01

    The functionality of fish protein hydrolysates (FPH) for the microencapsulation of fish oil was investigated. Muscle protein from sardine (Sardina pilchardus) and horse mackerel (Trachurus mediterraneus) was hydrolysed using Alcalase or trypsin. Physically stable emulsions suitable for spray-drying were obtained when using FPH with a degree of hydrolysis of 5%. Microencapsulation efficiency amounted to 98±0.1% and oxidative stability of the encapsulated oil over a period of twelve weeks was in a similar range as it is reported for other matrix systems. Therefore, the suitability of FPH for use in spray-dried emulsions has been shown for the first time. Since no clear correlation between the antioxidative activity of the FPH and the course of lipid oxidation could be established future research is required to more specifically characterise the molecular structure of the peptides and its impact on protein alteration and role in lipid oxidation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Fish larvae from the Gulf of California

    Directory of Open Access Journals (Sweden)

    Gerardo Aceves-Medina

    2003-03-01

    Full Text Available Taxonomic composition of fish larvae was analysed from 464 plankton samples obtained during 10 oceanographic surveys in the Gulf of California between 1984 and 1988. We identified 283 taxa: 173 species, 57 genera, and 53 families. Tropical and subtropical species predominated except during the winter, when temperate-subarctic species were dominant. The most abundant species were the mesopelagic Benthosema panamense, Triphoturus mexicanus and Vinciguerria lucetia, but the coastal pelagic species Engraulis mordax, Opisthonema spp., Sardinops caeruleus and Scomber japonicus were also prominent. The taxonomic composition of the ichthyoplankton shows the seasonality of the Gulf as well as environmental changes that occurred between the 1984-1987 warm period and the 1956-1957 cool period previously reported. The presence of E. mordax larvae as one of the most abundant species in the Gulf provides evidence of the reproduction of this species two years before the development of the northern anchovy fishery and the decline of the sardine fishery in the Gulf of California.

  20. A review of Kudoa-induced myoliquefaction of marine fish species in South Africa and other countries

    Directory of Open Access Journals (Sweden)

    Sun S. Henning

    2013-11-01

    Full Text Available Myoliquefaction of fish musculature results in customer quality complaints and in huge economic losses, especially with regard to Pacific hake (Merluccius productus, farm-reared Atlantic salmon (Salmo salar, South African pilchards (Sardinops ocellatus and Cape snoek (Thyrsites atun. Myoliquefaction, or jelly flesh, is caused by proteolytic enzymes released by the marine myxosporean parasite,Kudoa thyrsites, after the death of the fish. Currently there are no fast methods of detection for this microscopic parasite, and because myoliquefaction is evident only after 38-56 h post-mortem, infected fish inevitably reach the processor and/or consumer. Several methods of detection have been investigated, but most of these methods are time-consuming and/or result in destruction of the fish, and are thus impractical for fishing vessels and fish processors. Limited research is available on possible means of destroying or inhibiting the post-mortem activity of the parasitic proteolytic enzyme. Means such as manipulating post-mortem pH and temperature control have been suggested; leaving opportunities for research into food technology applications such as cold-chain management and ionising radiation.

  1. Optimization of α-tocopherol and ascorbyl palmitate addition for the stabilization of sardine oil

    Directory of Open Access Journals (Sweden)

    Morales-Medina, R.

    2015-06-01

    Full Text Available The purpose of the present work was to optimize the addition of natural antioxidants (α- tocopherol and ascorbyl palmitate for the stabilization of sardine oil rich in omega-3 PUFA. The optimal values for peroxide value (PV, which minimizes primary oxidation products, were obtained at low concentrations of α-tocopherol (50–207 ppm, high content of ascorbyl palmitate (450 ppm and 50 ppm citric acid. On the other hand, optimal values for p-anisidine value (AV, which minimizes secondary oxidation products, were found at medium concentrations of α-tocopherol (478–493 ppm, high contents of ascorbyl palmitate (390–450 ppm and 50 ppm citric acid. The conflicting effect of α-tocopherol on the individual optimization of PV and AV motivated the generation of a Pareto front (set of non inferior solutions employing the weighted-sum multi-objective optimization technique.El objetivo de este trabajo fue optimizar la adición de antioxidantes naturales (α-tocoferol y palmitato de ascorbilo para la estabilización de aceite de sardina rico en omega-3 PUFA. Bajas concentraciones de α-tocoferol (50–207 ppm combinadas con la adicción de antioxidantes secundarios como palmitato de ascorbilo (450 ppm y ácido cítrico (50 ppm, minimizaron la formación de hidroperóxidos en el aceite de sardina estudiado. Sin embargo, los productos secundarios de oxidación se redujeron para concentraciones medias de α-tocoferol (478–493 ppm, altas de palmitato de ascorbilo (390–450 ppm y 50 ppm de ácido cítrico. El efecto contradictorio de la concentración de α-tocoferol en la optimización individual del índice de peróxidos e índice de p-anisidina motivó la realización de una optimización simultánea que permite satisfacer la optimización de cada una de las variables individuales en el grado deseado.

  2. Glycerolysis of sardine oil catalyzed by a water dependent lipase in different tert-alcohols as reaction medium

    Directory of Open Access Journals (Sweden)

    Solaesa, Á. G.

    2015-12-01

    Full Text Available The production of monoacylglycerol rich in polyunsaturated fatty acids (PUFA via enzymatic glycerolysis of sardine oil in a homogeneous system was evaluated. Reactions were conducted in two different tert-alcohols. Based on the phase equilibrium data, the amount of solvent added to create a homogeneous system has been calculated and optimized. The immobilized lipase used in this work was Lipozyme RM IM from Rhizomucor miehei, a water dependent lipase. The amount of water added as well as other reaction parameters were studied to evaluate the optimum conditions for monoacylglycerol obtencion. An initial reactant mole ratio glycerol to sardine oil 3:1, 12 wt% of water based on glycerol content and 10 wt% of lipase loading (based on weight of reactants, achieved a MAG yield of around 70%, with nearly 28 wt% PUFA, with low free fatty acid content (lower than 18 wt%.En este trabajo se ha estudiado la producción de monoacilglicéridos, ricos en ácidos grasos poliinsaturados (AGPI, mediante glicerolisis enzimática de aceite de sardina. La reacción se ha llevado a cabo en dos tert-alcoholes para conseguir de esta forma un medio homogéneo de reacción. La cantidad de disolvente añadida al medio de reacción se ha optimizado y calculado en base al equilibrio de fases de los componentes del sistema. La lipasa empleada como biocatalizador ha sido la enzima inmovilizada Lipozyme RM IM de Rhizomucor miehei, una lipasa dependiente de agua. Se ha estudiado el efecto de distintos parámetros cinéticos, así como de la cantidad de agua añadida al medio de reacción, en la producción de monoacilglicéridos. De los resultados obtenidos, se puede concluir que, para una relación molar inicial de reactantes glicerol:aceite de sardina de 3:1, un 12 % en peso de agua en base al glicerol y un 10 % en peso de lipasa, en base al peso de reactantes; se puede llegar a conseguir un rendimiento en monoacilglicéridos alrededor del 70 % en peso, con casi un 28 % en

  3. A real-time PCR approach to detect predation on anchovy and sardine early life stages

    Science.gov (United States)

    Cuende, Elsa; Mendibil, Iñaki; Bachiller, Eneko; Álvarez, Paula; Cotano, Unai; Rodriguez-Ezpeleta, Naiara

    2017-12-01

    Recruitment of sardine (Sardina pilchardus Walbaum, 1792) and anchovy (Engraulis encrasicolus Linnaeus, 1758) is thought to be regulated by predation of their eggs and larvae. Predators of sardine and anchovy can be identified by visual taxonomic identification of stomach contents, but this method is time consuming, tedious and may underestimate predation, especially in small predators such as fish larvae. Alternatively, genetic tools may offer a more cost-effective and accurate alternative. Here, we have developed a multiplex real-time polymerase chain reaction (RT-PCR) assay based on TaqMan probes to simultaneously detect sardine and anchovy remains in gut contents of potential predators. The assay combines previously described and newly generated species-specific primers and probes for anchovy and sardine detection respectively, and allows the detection of 0,001 ng of target DNA (which corresponds to about one hundredth of the total DNA present in a single egg). We applied the method to candidate anchovy and sardine egg predators in the Bay of Biscay, Atlantic Mackerel (Scomber scombrus) larvae. Egg predation observed was limited primarily to those stations where sardine and/or anchovy eggs were present. Our developed assay offers a suitable tool to understand the effects of predation on the survival of anchovy and sardine early life stages.

  4. Molecular identification and description of the female of Nothoaspis reddelli (Ixodida: Argasidae) from a cave in southeastern Mexico.

    Science.gov (United States)

    Guzmán-Cornejo, Carmen; Paredes-León, Ricardo; Labruna, Marcelo B; Nava, Santiago; Venzal, José M

    2012-10-01

    Nothoaspis reddelli Keirans and Clifford, 1975 , was described from 3 males collected in Grutas de Xtacumbilxunaán, Campeche, Mexico, although females have remained undescribed for 37 yr. Recently adult females of this species were collected from Cueva de Villa Luz ( =  Cueva de las Sardinas, Cueva del Azufre), in Tapijulapa, Tabasco, Mexico. Here we present a morphological description of the female stage, together with 16S rDNA sequences that confirm the conspecificity of our female, male, and nymphal specimens. The female integument of the anterior portion of the dorsal surface is smooth (nothoaspis), appearing to consist of 3 large "subunits," 1 anterior and 2 posterior, each with a small sublateral "subunit" on either side. The remaining dorsal covered integument is a cell-like configuration. The hood is large and bluntly rounded, and visible dorsally. The spiracular plate is oval. It possesses 1 pair of posthypostomal setae. The palpal trochanter has 1 pair of setae and a 5/5 hypostome decreasing to 4/4 at the apex. There is a single central pore at the base of the hypostome.

  5. Feeding and ecomorphology of three clupeoids in the N Aegean Sea

    Directory of Open Access Journals (Sweden)

    P. K. KARACHLE

    2013-07-01

    Full Text Available The present study examines the feeding habits of anchovy (Engraulis encrasicolus, sardine (Sardina pilchardus and round sardinella (Sardinella aurita. The results are combined with previously published information on feeding-related morphological features (i.e. mouth area, intestine length and tail area in order to explore morphological affinities between species and the effect of ecomorphology on their co-existence. These species were mainly zooplanktivorous and no dietary differences were found with sex and season. Anchovy preyed mainly on Crustacea larvae, whereas sardine and round sardinella on Copepoda. In the majority of cases (>90%, the individual fractional trophic level of all species ranged between 3.0 and 3.5, classifying them as omnivores with preference to animals. The feeding-related morphological features differed between anchovy and the two other species, whereas only intestine length differed between sardine and round sardinella. The fact that round sardinella’s diet and morphology show a greater resemblance to those of sardine, further support the hypothesis that is a particulate feeder as sardine. Hence the three species tend to exploit the same food resources differently throughout the year. Thus, they make best use of the environment and its resources, in order to avoid competition and achieve optimum feeding conditions throughout their life cycles

  6. Born small, die young: Intrinsic, size-selective mortality in marine larval fish

    KAUST Repository

    Garrido, S.

    2015-11-24

    Mortality during the early stages is a major cause of the natural variations in the size and recruitment strength of marine fish populations. In this study, the relation between the size-at-hatch and early survival was assessed using laboratory experiments and on field-caught larvae of the European sardine (Sardina pilchardus). Larval size-at-hatch was not related to the egg size but was significantly, positively related to the diameter of the otolith-at-hatch. Otolith diameter-at-hatch was also significantly correlated with survival-at-age in fed and unfed larvae in the laboratory. For sardine larvae collected in the Bay of Biscay during the spring of 2008, otolith radius-at-hatch was also significantly related to viability. Larval mortality has frequently been related to adverse environmental conditions and intrinsic factors affecting feeding ability and vulnerability to predators. Our study offers evidence indicating that a significant portion of fish mortality occurs during the endogenous (yolk) and mixed (yolk /prey) feeding period in the absence of predators, revealing that marine fish with high fecundity, such as small pelagics, can spawn a relatively large amount of eggs resulting in small larvae with no chances to survive. Our findings help to better understand the mass mortalities occurring at early stages of marine fish.

  7. Determination of arsenic species in seafood samples from the Aegean Sea by liquid chromatography-(photo-oxidation)-hydride generation-atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Schaeffer, Richard [Department of Applied Chemistry, Corvinus University, Villanyi ut 29-35, 1118 Budapest (Hungary); Soeroes, Csilla [Department of Applied Chemistry, Corvinus University, Villanyi ut 29-35, 1118 Budapest (Hungary); Ipolyi, Ildiko [Department of Applied Chemistry, Corvinus University, Villanyi ut 29-35, 1118 Budapest (Hungary); Fodor, Peter [Department of Applied Chemistry, Corvinus University, Villanyi ut 29-35, 1118 Budapest (Hungary); Thomaidis, Nikolaos S. [Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Panepistiomopolis Zografou, 15776 Athens (Greece)]. E-mail: ntho@chem.uoa.gr

    2005-08-15

    In this study arsenic compounds were determined in mussels (Mytulis galloprovincialis), anchovies (Engraulis encrasicholus), sea-breams (Sparus aurata), sea bass (Dicentrarchus labrax) and sardines (Sardina pilchardus) collected from Aegean Sea using liquid chromatography-photo-oxidation-hydride generation-atomic fluorescence spectrometry [LC-(PO)-HG-AFS] system. Twelve arsenicals were separated and determined on the basis of their difference in two properties: (i) the pK {sub a} values and (ii) hydride generation capacity. The separation was carried out both with an anion- and a cation-exchange column, with and without photo-oxidation. In all the samples arsenobetaine, AB was detected as the major compound (concentrations ranging between 2.7 and 23.1 {mu}g g{sup -1} dry weight), with trace amounts of arsenite, As(III), dimethylarsinic acid, DMA and arsenocholine, AC, also present. Arsenosugars were detected only in the mussel samples (in concentrations of 0.9-3.6 {mu}g g{sup -1} dry weight), along with the presence of an unknown compound, which, based on its retention time on the anion-exchange column Hamilton PRP-X100 and a recent communication [E. Schmeisser, R. Raml, K.A. Francesconi, D. Kuehnelt, A. Lindberg, Cs. Soeroes, W. Goessler, Chem. Commun. 16 (2004) 1824], is supposed to be a thio-arsenic analogue.

  8. {sup 137}Cs Distribution in the Northern Adriatic Sea (2006-2010)

    Energy Technology Data Exchange (ETDEWEB)

    Pavicic-Hamer, D. [' Ruder Boskovic' Institute, Centre for Marine Research, Rovinj (Croatia); Barisic, D., E-mail: pavicic@cim.irb.hr [' Ruder Boskovic' Institute, Division for Marine and Environmental Research, Zagreb (Croatia)

    2013-07-15

    Artificial radioactivity in the northern Adriatic Sea was assessed by analysis of {sup 137}Cs concentrations in seawater, sediment and marine organisms. A comparison of radioactive contamination was made between different parts of the marine ecosystem including the area of the Po river delta, the protected area of the Lim bay and the Rovinj coastal area in the period from 2006 to 2010. In the area of the Po river delta {sup 137}Cs concentrations in seawater had decreased back to pre-Chernobyl values (2.48 Bq/m), although in sediment they were slightly higher (8.70 Bq/kg). Inside the Lim bay area {sup 137}Cs concentrations in surface water were low (1.93 Bq/m) and, in the mussel Mytilus galloprovincialis, even undetectable in this period. In the Rovinj coastal area {sup 137}Cs concentrations in surface water remained constant (2.23 Bq/m), as well as in the surface sediment (1.88 Bq/kg). {sup 137}Cs concentrations were detectable at very low activity levels in Mugil cephalus and Sardina pilchardus. The data indicate that some species such as the intertidal brown algae Fucus virsoides and the benthic fish Mullus barbatus are better bio-accumulators of {sup 137}Cs than others. These species should be used as bio-indicators in future monitoring schemes in the A driatic Sea. (author)

  9. [Dynamics of numbers of commercial fish in early ontogenesis in different areas of the Central-Eastern Atlantic].

    Science.gov (United States)

    Arkhipov, A G; Mamedov, A A; Simonova, T A; Tenitskaia, I A

    2011-01-01

    Changes in the quantitative composition of mass fish species at early stages of ontogenesis in different areas of the Central-Eastern Atlantic (CEA) in warm and cold seasons in 1994-2008 were analyzed in the paper. The most widespread representatives of ichthyocenosis of CEA were: European pilchard (Sardina pilchardus), common scad (Trachurus trachurus), round sardinella (Sardinella aurita), and West-African scad (Trachrus trecae). The data obtained indicate that, within the economic zone of Morocco, fluctuations of numbers at early stages of development in European pilchard and common scad are close over the entire water area under consideration (36 degrees-21 degrees N). The regularities of fluctuations of the numbers of ichthyoplankton are similar to the interannual changes in the biomass of fish in the area of Morocco. In the area of Mauritania (21 degrees-16 degrees N), fluctuations of numbers of the early stages of development of commercial fish cannot be unambiguously correlated with changes in the biomass of adult fish. It is known that, in the economic zone of Mauritania, there are Senegal-Mauritanian populations of round sardinella and West-African scad that inhabit waters of different states and are not completely assessed by our surveys. Therefore, no obvious relation was observed between the considered data.

  10. Vertical patterns of ichthyoplankton at the interface between a temperate estuary and adjacent coastal waters: Seasonal relation to diel and tidal cycles

    Science.gov (United States)

    Primo, Ana Lígia; Azeiteiro, Ulisses M.; Marques, Sónia C.; Ré, Pedro; Pardal, Miguel A.

    2012-07-01

    Vertical distribution and migration pattern of ichthyoplankton assemblage in the Mondego estuary were investigated in relation to diel and tidal cycle. Summer and winter communities were sampled, at surface and bottom, over a diel cycle during spring and neap tides at a fixed station at the mouth of the estuary. Summer presented higher larvae density mainly of Pomatoschistus spp., Gobius niger and Parablennius pilicornis. Main species in winter assemblages were Pomatoschistus spp. and Sardina pilchardus. There were no differences between depth stratums across diel or tide cycle. Nevertheless, main species larval densities showed significant periodic variation associated with tide (M2) and diel (K1) cycles presenting generally, higher density at night and around low tide. Conversely, vertical patterns observed could not be related with diel or tidal cycle. Tough, main species presented some extent of vertical migration. Vertical patterns observed appear to be related to seasonal stratification and river flow, increasing amplitude during periods of less stratification and lower water currents. Present study provides a better understanding of ichthyoplankton vertical movement patterns and of small scale dynamics at the interface of two coastal European systems.

  11. Temporal and cross-shelf distribution of ichthyoplankton in the central Cantabrian Sea

    Science.gov (United States)

    Rodriguez, J. M.

    2008-09-01

    Environmental variables have been measured and sampling for ichthyoplankton has been conducted monthly, since April 2001, at three stations, located at the inner (1), middle (2) and outer (3) shelf of the central Cantabrian Sea. This paper presents the results of the study of the ichthyoplankton collected from July 2001 to June 2004. Fish larvae from 99 species, belonging to 37 families, were identified. Families with higher number of species were Gadidae, Sparidae and Labridae. The larval fish assemblage was dominated by pelagic fish species, with Sardina pilchardus, as the most abundant. There was a pronounced spring peak in larval abundance, dominated by S. pilchardus. A smaller peak, dominated by S. pilchardus and Micromesistius poutassou, was recorded in late winter at Stns 2 and 3. This pattern was evident for the three-year study. Results also indicate that this study was limited to the coastal larval fish assemblage inhabiting the central Cantabrian Sea shelf. This assemblage was temporally structured into other three assemblages: winter, late winter-spring and summer-autumn. Temperature was apparently a key factor in larval fish assemblage succession. In a scenario of global warming, this study constitutes a basis to evaluating the ongoing changes in the pelagic coastal ecosystem of the central Cantabrian Sea.

  12. The ichthyoplankton assemblage and the environmental variables off the NW and N Iberian Peninsula coasts, in early spring

    Science.gov (United States)

    Rodriguez, J. M.; Gonzalez-Nuevo, G.; Gonzalez-Pola, C.; Cabal, J.

    2009-05-01

    Ichthyoplankton and mesozooplankton were sampled and fluorescence and physical environmental variables were measured off the NW and N Iberian Peninsula coasts, during April 2005. A total of 51 species of fish larvae, belonging to 26 families, were recorded. Sardina pilchardus, with 43.8% and 58.7% of the total fish egg and larval catches, respectively, dominated the ichthyoplankton assemblage. The study area was divided by a cross-shelf frontal structure into two hydrographic regions that coincided with the Atlantic and Cantabrian geographic regions. Ichthyoplankton abundance was higher in the Cantabrian region while larval diversity was higher in the Atlantic region. This was the main alongshore variability in the structure of the larval fish assemblage. Nevertheless, the stronger variability, related with the presence of a shelf-slope front, was found in the central-eastern Cantabrian region where two major larval fish assemblages, an "outer" and a "coastal", were distinguished. The Atlantic region, where the shelf-slope front was not found, was inhabited by a single larval fish assemblage. Canonical correspondence analysis revealed that, off the NW and N Iberian Peninsula coasts, the horizontal distribution of larval fish species in early spring may be explained by a limited number of environmental variables. Of these, the most important were the physical variables depth and sea surface temperature.

  13. Born small, die young: Intrinsic, size-selective mortality in marine larval fish

    KAUST Repository

    Garrido, S.; Ben-Hamadou, R.; Santos, A.M.P.; Ferreira, S.; Teodó sio, M.A.; Cotano, U.; Irigoien, Xabier; Peck, M.A.; Saiz, E.; Ré , P.

    2015-01-01

    Mortality during the early stages is a major cause of the natural variations in the size and recruitment strength of marine fish populations. In this study, the relation between the size-at-hatch and early survival was assessed using laboratory experiments and on field-caught larvae of the European sardine (Sardina pilchardus). Larval size-at-hatch was not related to the egg size but was significantly, positively related to the diameter of the otolith-at-hatch. Otolith diameter-at-hatch was also significantly correlated with survival-at-age in fed and unfed larvae in the laboratory. For sardine larvae collected in the Bay of Biscay during the spring of 2008, otolith radius-at-hatch was also significantly related to viability. Larval mortality has frequently been related to adverse environmental conditions and intrinsic factors affecting feeding ability and vulnerability to predators. Our study offers evidence indicating that a significant portion of fish mortality occurs during the endogenous (yolk) and mixed (yolk /prey) feeding period in the absence of predators, revealing that marine fish with high fecundity, such as small pelagics, can spawn a relatively large amount of eggs resulting in small larvae with no chances to survive. Our findings help to better understand the mass mortalities occurring at early stages of marine fish.

  14. Preparation of triacylglycerols rich in omega-3 fatty acids from sardine oil using a Rhizomucor miehei lipase: focus in the EPA/DHA ratio.

    Science.gov (United States)

    Bispo, Paulo; Batista, Irineu; Bernardino, Raul J; Bandarra, Narcisa Maria

    2014-02-01

    The increasing evidence on the differential biochemical effects of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) raises the need of n-3 highly unsaturated fatty acid concentrates with different amounts of these fatty acids. In the present work, physicochemical and enzymatic techniques were combined to obtain acylglycerols, mainly triacylglycerols (TAG), rich in n-3 fatty acids. Sardine oil was obtained by washing sardine (Sardina pilchardus) mince with a NaHCO3 solution, hydrolyzed in a KOH-ethanol solution, and concentrated with urea. The esterification reaction was performed in the stoichiometric proportion of substrates for re-esterification to TAG, with 10 % level of Rhizomucor miehei lipase based on the weight of substrates, without any solvent, during 48 h. This procedure led to approximately 88 % of acylglycerols, where more than 66 % were TAG and the concentration of n-3 fatty acids was higher than 60 %, the EPA and DHA ratio (EPA/DHA) was 4:1. The content of DHA in the unesterifed fraction (free fatty acids) increased from 20 to 54 %, while the EPA level in the same fraction decreased from 33 to 12.5 % (EPA/DHA ratio ≈1:4). Computational methods (density functional theory calculations) have been carried out at the B3LYP/6-31G(d,p) level to explain some of the experimental results.

  15. 210Po and 210Pb trophic transfer within the phytoplankton-zooplankton-anchovy/sardine food web: a case study from the Gulf of Lion (NW Mediterranean Sea).

    Science.gov (United States)

    Strady, Emilie; Harmelin-Vivien, Mireille; Chiffoleau, Jean François; Veron, Alain; Tronczynski, Jacek; Radakovitch, Olivier

    2015-05-01

    The transfer of (210)Po and (210)Pb in the food web of small pelagic fishes (from phytoplankton and zooplankton to anchovy Engraulis encrasicolus and sardine Sardina pilchardus) is investigated in the Gulf of Lion (GoL). We present original data of (210)Po and (210)Pb activity concentrations, C and N stable isotope ratios, measured (i) from different size classes of phytoplankton and zooplankton during spring and winter in different environments of the GoL, and (ii) in two fish species. Significant spatial patterns based on (210)Po, (210)Pb activity concentrations and (210)Po/(210)Pb ratios in the different plankton size classes are evidenced by hierarchical clustering, both in spring and winter. This variability, also observed for C and N stable isotopes ratios, is connected to local specific pelagic habitats and hydrodynamics. The sampling strategy suggests that (210)Po bioaccumulation in the GoL remains at a constant level from the first (dominated by phytoplankton) to the second trophic level (zooplankton), while (210)Pb bioaccumulation shows an increase in winter. Based on stable N isotope ratios and (210)Po activity concentrations measured in anchovies and sardines, we evidence (210)Po bio-magnification along the trophic food web of these two planktivorous pelagic fishes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Diet of bottlenose dolphins (Tursiops truncatus from the Gulf of Cadiz: Insights from stomach content and stable isotope analyses.

    Directory of Open Access Journals (Sweden)

    Joan Giménez

    Full Text Available The ecological role of species can vary among populations depending on local and regional differences in diet. This is particularly true for top predators such as the bottlenose dolphin (Tursiops truncatus, which exhibits a highly varied diet throughout its distribution range. Local dietary assessments are therefore critical to fully understand the role of this species within marine ecosystems, as well as its interaction with important ecosystem services such as fisheries. Here, we combined stomach content analyses (SCA and stable isotope analyses (SIA to describe bottlenose dolphins diet in the Gulf of Cadiz (North Atlantic Ocean. Prey items identified using SCA included European conger (Conger conger and European hake (Merluccius merluccius as the most important ingested prey. However, mass-balance isotopic mixing model (MixSIAR, using δ13C and δ15N, indicated that the assimilated diet consisted mainly on Sparidae species (e.g. seabream, Diplodus annularis and D. bellottii, rubberlip grunt, Plectorhinchus mediterraneus, and common pandora, Pagellus erythrinus and a mixture of other species including European hake, mackerels (Scomber colias, S. japonicus and S. scombrus, European conger, red bandfish (Cepola macrophthalma and European pilchard (Sardina pilchardus. These contrasting results highlight differences in the temporal and taxonomic resolution of each approach, but also point to potential differences between ingested (SCA and assimilated (SIA diets. Both approaches provide different insights, e.g. determination of consumed fish biomass for the management of fish stocks (SCA or identification of important assimilated prey species to the consumer (SIA.

  17. A real-time PCR assay to estimate invertebrate and fish predation on anchovy eggs in the Bay of Biscay

    KAUST Repository

    Albaina, A.

    2015-02-01

    In order to investigate the role of predation on eggs and larvae in the recruitment of anchovy (Engraulis encrasicolus), sardine (Sardina pilchardus), sprat (Sprattus sprattus) and 52 macrozooplankton taxa were assayed for anchovy remains in the gut during the 2010 spawning season using a molecular method. This real-time PCR based assay was capable of detecting 0.005. ng of anchovy DNA (roughly 1/100 of a single egg assay) in a reliable way and allowed detecting predation events up to 6. h after ingestion by small zooplankton taxa. A total of 1069 macrozooplankton individuals, 237 sardines and 213 sprats were tested. Both fish species and 32 macrozooplankton taxa showed remains of anchovy DNA within their stomach contents. The two main findings are (1) that the previously neglected macrozooplankton impact in anchovy eggs/larvae mortality is in the same order of magnitude of that due to planktivorous fishes and that, (2) the predation pressure was notably different in the two main spawning centers of Bay of Biscay anchovy. While relatively low mortality rates were recorded at the shelf-break spawning center, a higher predation pressure from both fish and macrozooplankton was exerted at the shelf one.

  18. Fish community structure in San Agustín Bay, Huatulco, Mexico Estructura comunitaria de peces en bahía San Agustín, Huatulco, México

    Directory of Open Access Journals (Sweden)

    MARTÍN RAMÍREZ-GUTIÉRREZ

    2007-12-01

    Full Text Available San Agustín bay is one of the most important bays in the Huatulco National Park because it includes the broadest coral reef surface of this park, which supports a great diversity of fish species. The importance of the present work is that describes quantitatively, for first time, the fish assemblage of this reef area. Visual censuses were realized on transects, according to the coral reef size, on coral and rocky reefs, and coral rubble environments. 64 species, 46 genus and 29 families were registered. Seasonal variation in fish assemblage was observed; reflecting the influence of pelagic shoaling species associated with the Gulf of Tehuantepec upwelling, during the dry season. Thus species were Selar crumenophthalmus, Caranx caninus, and Sardinops caeruleus. For species more closely associated to the reef habitat little seasonal variation was observed for each species, except Chromis atrilobata, which exhibited high density during the dry season. Pomacentrids exhibited more affinity for coral reef, labrids and haemulids for coral rubble environments. The highest diversity values were on coral rubble and the highest density was on the coral reef. Our study suggests that in this region, the Gulf of Tehuantepec upwelling is an important factor as well as the heterogeneity of habitats in shaping the fish assemblages, which must be protected to maintain the biodiversity of this important ecosystemLa bahía de San Agustín es una de las más importantes del Parque Nacional Huatulco debido a que incluye al arrecife coralino más grande de este parque, el cual alberga una gran diversidad de especies de peces. La importancia del presente trabajo es describir cuantitativamente, por primera vez, la comunidad de peces de este habitat de arrecifes. Para ello se realizaron censos visuales en transectos de acuerdo al tamaño de los ambientes coralino, rocoso y de escombros. 64 especies, 46 géneros y 29 familias fueron registrados. Se observaron cambios

  19. [Mercury concentration of fish in Tokyo Bay and the surrounding sea area].

    Science.gov (United States)

    Zhang, R; Kashima, Y; Matsui, M; Okabe, T; Doi, R

    2001-07-01

    Total mercury in the muscles of three fish species was analyzed in fish caught in Tokyo Bay and the surrounding sea areas, Sagami Bay and Choshi. Tokyo Bay is a semi-closed sea area surrounded by Tokyo, Kanagawa and Chiba prefectures. Sagami Bay and Choshi are open to the Pacific Ocean. A total of 412 fish consisting of northern whiting (Sillago japonica), flatfish (Limanda yokohamae) and sardine (Sardinops melanosticta) were caught in these areas over a 6 months period from November 1998 to April 1999. Total mercury concentration ranged from 0.008-0.092 microgram/g (wet wt.) in northern whiting, 0.006-0.065 microgram/g in flatfish and 0.001-0.045 microgram/g in sardine. All concentrations were below the restriction limit of fish mercury in Japan, 0.4 microgram/g of total mercury concentration. A significant correlation was found between mercury concentrations and body length or body weight in northern whiting and flatfish, irrespective of the sea area. A correlation was also found between mercury concentration in fish and their feeding habits: among the 3 species caught in the same area, crustacean feeding northern whiting had the highest, polychaete feeding flatfish moderate, and plankton feeding sardine had the lowest mercury concentration. In a comparison of mercury concentration in the same species caught in different sea areas, a higher concentration was noted in fish caught in the semi-closed sea area of Tokyo Bay, than in fish caught in the open sea areas of Sagami Bay and Choshi. This difference was most marked in fish caught at the bottom of Tokyo Bay and we considered that the mercury concentration of seawater and sediment in these areas was the cause of mercury accumulation in fish. These findings suggest that improved water quality control and environmental monitoring is necessary in semi-closed sea areas such as Tokyo Bay.

  20. Cestodes of the blue shark, Prionace glauca (Linnaeus 1758), (Carcharhiniformes: Carcharhinidae), off the west coast of Baja California Sur, Mexico.

    Science.gov (United States)

    Méndez, Oscar; Galván-Magaña, Felipe

    2016-03-03

    The cestode species recovered from the spiral intestines of 27 blue sharks (Prionace glauca) (Linnaeus, 1758) are reported from the western coast of Baja California Sur (BCS). The sampling was undertaken on a monthly basis from January 2003 to January 2004. The helminthological examination indicated the presence of four species of cestodes: Platybothrium auriculatum Yamaguti, 1952; Prosobothrium japonicum Yamaguti, 1934; Anthobothrium caseyi (Yamaguti, 1934) Ruhnke & Caira, 2009; and Paraorygmatobothrium prionacis (Yamaguti, 1934) Ruhnke, 1994. Of all the 27 sharks examined, 88.8% were infected with at least one cestode species. The most frequent species was P. auriculatum infecting 85% of the spiral intestines examined. In contrast the species with the highest mean intensity was P. prionacis (80.4 200). The species richness of cestodes in P. glauca is very similar in other regions of the world despite its wide distribution; however, this richness is low compared with other species of sharks within the same family. The feeding and host-specific are important factors that influence the parameters of infection of cestodes in this shark. On the west coast of BCS, Prionace glauca feeds mainly on red crab Pleuroncodes planipes Stimpson, 1860; squids Gonatus californiensis Young, 1972, Ancistrocheirus lesueurii (D'Orbigny, 1842), Haliphron atlanticus Steenstrup, 1861, and low proportion of fish teleosts as Merluccius productus (Ayres, 1855), Sardinops sp. Hubbs, 1929 and Scomber japonicus Houttuyn, 1872. We speculate that these prey could be involved as the second intermediate hosts of these cestodes, as in other members of these genera, although the life cycles of none are known.

  1. Using non-systematic surveys to investigate effects of regional climate variability on Australasian gannets in the Hauraki Gulf, New Zealand

    Science.gov (United States)

    Srinivasan, Mridula; Dassis, Mariela; Benn, Emily; Stockin, Karen A.; Martinez, Emmanuelle; Machovsky-Capuska, Gabriel E.

    2015-05-01

    Few studies have investigated regional and natural climate variability on seabird populations using ocean reanalysis datasets (e.g. Simple Ocean Data Assimilation (SODA)) that integrate atmospheric information to supplement ocean observations and provide improved estimates of ocean conditions. Herein we use a non-systematic dataset on Australasian gannets (Morus serrator) from 2001 to 2009 to identify potential connections between Gannet Sightings Per Unit Effort (GSPUE) and climate and oceanographic variability in a region of known importance for breeding seabirds, the Hauraki Gulf (HG), New Zealand. While no statistically significant relationships between GSPUE and global climate indices were determined, there was a significant correlation between GSPUE and regional SST anomaly for HG. Also, there appears to be a strong link between global climate indices and regional climate in the HG. Further, based on cross-correlation function coefficients and lagged multiple regression models, we identified potential leading and lagging climate variables, and climate variables but with limited predictive capacity in forecasting future GSPUE. Despite significant inter-annual variability and marginally cooler SSTs since 2001, gannet sightings appear to be increasing. We hypothesize that at present underlying physical changes in the marine ecosystem may be insufficient to affect supply of preferred gannet main prey (pilchard Sardinops spp.), which tolerate a wide thermal range. Our study showcases the potential scientific value of lengthy non-systematic data streams and when designed properly (i.e., contain abundance, flock size, and spatial data), can yield useful information in climate impact studies on seabirds and other marine fauna. Such information can be invaluable for enhancing conservation measures for protected species in fiscally constrained research environments.

  2. Mercury in Forage Fish from Mexico and Central America: Implications for Fish-Eating Birds.

    Science.gov (United States)

    Elliott, John E; Kirk, David A; Elliott, Kyle H; Dorzinsky, Jessica; Lee, Sandi; Inzunza, Ernesto Ruelas; Cheng, Kimberly M T; Scheuhammer, Tony; Shaw, Patrick

    2015-11-01

    Mercury (Hg) is a global contaminant of aquatic food chains. Aquatic birds, such as the osprey (Pandion haliaetus), with migratory populations breeding in Canada and the northern United States and wintering in the Central and South America, can be exposed to mercury on both the breeding and wintering ranges. We examined Hg levels in 14 fish taxa from 24 osprey wintering sites identified from satellite telemetry. Our main goal was to determine whether fish species that feature in the diet of overwintering and resident fish-eating birds reached toxicity thresholds for Hg. Mean Hg levels in fish whole carcasses ranged from a high of 0.18 µg g(-1) (wet weight) in Scomberomorus sierra to a low of 0.009 µg g(-1) in Catostomidae. Average Hg levels were within published toxicity threshold values in forage fish for only two sites in Mexico (Puerto Vallarta and San Blas Estuary), and all were marine species, such as mackerel (Scomberomorus sierra), sea catfish (Ariopus spp.), and sardinas species (Centropomus spp.). Except for one sample from Nicaragua, sea catfish from Puerto Morazan, none of the fish from sites in Central America had Hg levels which exceeded the thresholds. Nonmetric multidimensional scaling revealed geographical differences in Hg levels with significant pairwise differences between sites along the Pacific Ocean (Mexico) versus the Bay of Campeche, partly due to differences in species composition of sampled fish (and species distributions). Hg increased with trophic level, as assessed by nitrogen stable isotope ratios (δ(15)N but not δ(13)C), in freshwater and marine, but not estuarine, environments. Hg concentrations in forage fish do not account for the elevated Hg reported for many osprey populations on the breeding grounds, thus primary sources of contamination appear to be in the north.

  3. Desodorización de aceite de pescado mediante destilación a alto vacío: preservación de las características químicas del aceite

    Directory of Open Access Journals (Sweden)

    Nieto, S.

    1993-02-01

    Full Text Available The construction and the operation conditions of a high vacuum glass-equipment for deodorizing sardine oil at laboratory scale is described. The equipment working at 120°C and at a pressure of 0.05-0.1 mmHg maintains unchanged the n-3 fatty acid composition of the oil producing a considerable reduction in the cholesterol and peroxide content of the oil. The stripper, having a throughput of 1500-1800 mL/hr, allows the obtaining of a high quality fish oil suitable for experimental and for pharmacological and/or nutritional applications.

    Se describe la construcción y condiciones de operación de un destilador de vidrio de alto vacío que permite, a escala de laboratorio, la desodorización del aceite de sardina española. El equipo operando a temperaturas no superiores a 120°C y a una presión constante de 0,05-0,1 mmHg no altera la composición de ácidos grasos n-3 del aceite y permite una disminución considerable del colesterol y de los peróxidos orgánicos. La destilación permite obtener un aceite de alta calidad con un rendimiento de 1500-1800 mL/hr que puede ser utilizado para fines experimentales o para uso farmacológico y/o nutricional.

  4. Fine-scale tracking and diet information of a marine predator reveals the origin and contrasting spatial distribution of prey

    Science.gov (United States)

    Alonso, Hany; Granadeiro, José P.; Dias, Maria P.; Catry, Teresa; Catry, Paulo

    2018-03-01

    The distribution of many marine organisms is still poorly understood, particularly in oceanic regions. Seabirds, as aerial predators which cover extensive areas across the oceans, can potentially be used to enhance our knowledge on the distribution and abundance of their prey. In this study, we combined tracking data and dietary data from individual Cory's shearwaters Calonectris borealis (n = 68) breeding in Selvagens archipelago, Madeira, Portugal, during the chick-rearing periods of 2011 and 2016, in order to infer prey origin within shearwaters' main foraging areas. The digestion state of each prey item in the diet was assessed and classified; and compared to digestion states from known prey items fed to captive birds. In a novel approach, we combined tracking data with information on the prey digestion duration and data on the transit times from foraging grounds to the colony to estimate the location of prey capture. We found a consistent heterogeneity in prey distribution across four different marine domains: Selvagens, deep-sea, seamounts, and continental shelf. In oceanic areas, the chub mackerel Scomber colias, the main prey of Cory's shearwaters, was strongly associated with seamounts and insular shelves, whereas oceanic species like pilot-fish, flying-squid, flying-fish were clearly associated with deep-sea waters. Sardines Sardina pilchardus, anchovies Engraulis encrasicolus and other coastal species were associated with the African shelf. Prey origin assignment was robust across three different sets of assumptions, and was also supported by information on the digestion state of prey collected over a large independent sampling period (671 samples, collected in 2008-2010). The integration of fine-scale dietary and foraging trip data from marine predators provides a new framework to gain insights into the distribution and abundance of prey species in poorly known oceanic areas.

  5. The Radiological Condition of 137 Cs in the Northern Adriatic Sea (2006-2007)

    International Nuclear Information System (INIS)

    Pavicic-Hamer, D.; Lulic, S.

    2008-01-01

    Over the past 30 years, the Croatian Rudjer Boskovic Institute, Center for Marine Research Rovinj has studied the levels and distribution of long-lived radionuclides in different marine samples. Artificial radioactivity in the northern Adriatic Sea was assessed by analysis of the concentration of 137Cs in seawater, sediment and marine organisms. A comparison of radioactive contamination was made between different ecosystems including in front of the river Po delta, the protected area of Lim bay and the Rovinj coastal area from 2006 to 2007. At the station which was under the direct influence of the Po river discharge the concentrations of 137Cs in seawater were back to pre-Chernobyl values (2.65 Bq m-3), although in sediment values were slightly higher (9.06 Bq/kg). Inside Lim bay the concentrations of 137Cs in seawater were low (1.99 Bq m -3 ) and in mussel Mytilus galloprovincialis were undetectable in this period. The concentrations of 137Cs in seawater in the surface layer in the Rovinj coastal area remained constant (2.43 Bq m-3), as were found within the top sediment layer (2.15 Bq/kg). The concentrations of 137Cs were detectable at very low levels in Mugil cephalus and Sardina pilchardus. Fucus virsoides and Mullus barbatus can be considered a good bio indicator of monitoring radio contamination in the Adriatic Sea. The radiological status of 137Cs in the Adriatic Sea has returned to the pre-accident level, taking into consideration their natural fluctuations due to physico-chemical and hydrological parameters in the investigated area. Such knowledge of radioactive contamination could be useful in the estimation of the state of the environment and as an input to plans for the protection of the Adriatic Sea.(author)

  6. Variation and temporal patterns in the composition of the surface ichthyoplankton in the southern Bay of Biscay (W. Atlantic)

    Science.gov (United States)

    d'Elbée, Jean; Castège, Iker; Hémery, Georges; Lalanne, Yann; Mouchès, Claude; Pautrizel, Françoise; D'Amico, Frank

    2009-05-01

    From September 2000 to December 2006, surface plankton samples were collected on a monthly basis, from a station located in the southern Bay of Biscay (43°37N; 1°43W France), near the deep Capbreton canyon. In this paper, the results for the ichthyoplankton assemblage are presented. Among the 62 taxa recorded, only 35 were present in the larval stage whilst only 10 were represented by their eggs. Taxa represented by both stages (eggs+larvae; N=17) had the highest abundance. The presence in the surface plankton assemblage of species, at either or both stage, is interpreted within the context of the bathymetric distribution of species. The maxima in abundance and diversity occurred in February-March, for eggs, and May-June, for larvae. This 3-month time-lag between the stages is proposed to be related to the timing of egg spawning and larval recruitment to the pelagic environment. Mean egg abundances (82.4±29.8 eggs/10 m 2) were 10-fold higher than the larval abundances (7.1±1.8 larvae/10 m 2). Despite pronounced monthly variability, no statistically significant decrease in either egg or larvae abundance was observed during this 6-year study period. Compared with previous published studies, this study shows that the peak in ichthyoplankton diversity occurred two months earlier. In addition, the spawning period occurred over the whole year, even during autumn and winter. Using ordination techniques, the annual sequence appearance of taxa are described at the study site: Gadiforms, Ammodytidae and Pleuronectiforms were present during the winter whilst Sparidae, Blennidae, Labridae and Gobiidae, formed the summer group. Only three species, European anchovy Engraulis encrasicolus, European pilchard Sardina pilchardus and Atlantic horse mackerel Trachurus trachurus were recorded throughout the year.

  7. 210Po and 210Pb trophic transfer within the phytoplankton–zooplankton–anchovy/sardine food web: a case study from the Gulf of Lion (NW Mediterranean Sea)

    International Nuclear Information System (INIS)

    Strady, Emilie; Harmelin-Vivien, Mireille; Chiffoleau, Jean François; Veron, Alain; Tronczynski, Jacek; Radakovitch, Olivier

    2015-01-01

    The transfer of 210 Po and 210 Pb in the food web of small pelagic fishes (from phytoplankton and zooplankton to anchovy Engraulis encrasicolus and sardine Sardina pilchardus) is investigated in the Gulf of Lion (GoL). We present original data of 210 Po and 210 Pb activity concentrations, C and N stable isotope ratios, measured (i) from different size classes of phytoplankton and zooplankton during spring and winter in different environments of the GoL, and (ii) in two fish species. Significant spatial patterns based on 210 Po, 210 Pb activity concentrations and 210 Po/ 210 Pb ratios in the different plankton size classes are evidenced by hierarchical clustering, both in spring and winter. This variability, also observed for C and N stable isotopes ratios, is connected to local specific pelagic habitats and hydrodynamics. The sampling strategy suggests that 210 Po bioaccumulation in the GoL remains at a constant level from the first (dominated by phytoplankton) to the second trophic level (zooplankton), while 210 Pb bioaccumulation shows an increase in winter. Based on stable N isotope ratios and 210 Po activity concentrations measured in anchovies and sardines, we evidence 210 Po bio-magnification along the trophic food web of these two planktivorous pelagic fishes. - Highlights: • 210 Po and 210 Pb activity concentrations in plankton vary up to a factor of two in the Gulf of Lion (East vs West). • 210 Po and 210 Pb variability is connected to local specific pelagic habitats. • Bio-magnification of 210 Po is evidenced in anchovy/sardine foodwebs

  8. Energy density of zooplankton and fish larvae in the southern Catalan Sea (NW Mediterranean)

    Science.gov (United States)

    Barroeta, Ziortza; Olivar, M. Pilar; Palomera, Isabel

    2017-06-01

    In marine communities, energy of small planktonic organisms is transferred to their predators through feeding. The energy accumulated as organic substances by the different plankton organisms (Energetic Density content, ED) has been analysed in high latitudes and tropical areas, but not in the Mediterranean Sea. In this study, we approach this type of investigation for Mediterranean plankton through measures of total calorimetric content using an oxygen bomb calorimeter. We examined the spatiotemporal variation in the ED of microplankton (50-200 μm) and mesozooplankton (200-2000 μm), and two plankton-consumers, sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) larvae. The study was carried out during the winter and summer of 2013 off the Ebro River Delta (NW Mediterranean Sea). Both plankton fractions showed a more coastal distribution and higher biomasses during winter, the period of sardine larvae occurrences, in front of a wider cross-shelf distribution and lower biomasses in summer, when anchovy appeared. ED values increased with the size of each plankton component, i.e., microzooplankton < mesozooplankton < fish larvae. A tendency for higher plankton ED in the winter period was observed, although being only significant for coastal zone, associated to the more productive waters there. Sardine and anchovy larvae showed an increasing trend in the amount of energy during development, with significantly lower ED between early larvae (6-10 mm standard length) and late postflexion stages (16-20 mm standard length). Small larvae of both species departed from a similarly low ED content, but in the next two size classes sardine larvae showed higher ED values than anchovy, being significantly higher in the 16-20 mm size class. Information on larval feeding patterns and larval growth rates for each species were used to discuss differences in energy allocation strategies.

  9. Spatial distribution and species composition of small pelagic fishes in the Gulf of California

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    Edgar Lanz

    2008-06-01

    regiones, incluyen áreas arbitrarias y homogéneas sobre las cuales se realiza estadística básica o inferencias relacionadas con la distribución y la abundancia de estos recursos. El presente trabajo describe una metodología para la regionalización y el análisis de la actividad pesquera de pelágicos menores en el Golfo de California basado en los patrones espaciales de la información de lances y capturas utilizando herramientas de Sistemas de Información Geográfica (SIG. La información pesquera, con atributos espaciales, provino de bitácoras de pesca para el periodo comprendido de octubre 2002 a junio 2007. Los datos de lances y capturas fueron transformados a un Índice de Región Ponderada (WRI utilizando operadores de lógica difusa. El WRI reveló centros de actividad pesquera caracterizados por áreas con los valores más altos de WRI y se obtuvo un orden jerárquico para denotar la importancia relativa de cada región, siendo las regiones de Guaymas, el Desemboque de Caborca, Isla Patos y Bahía San Rafael, los más prominentes. El análisis de la frecuencia relativa de la composición de especies mostró que la sardina Monterrey tuvo una abundancia relativa mayor al 80% en la región de las Grandes Islas y permaneció como la especie más importante en las regiones del alto golfo, mientras que en la parte central del golfo las abundancias de la sardina Monterrey y la ancho-veta norteña estuvieron más equilibradas. La abundancia relativa de la macarela fue significativamente mayor en la región de la Isla Patos, respecto a cualquier otra región. La región de Guaymas mostró la mayor composición relativa de anchoveta norteña, en contraste con los más bajos valores de sardina Monterrey. El Desemboque de Caborca mostró la mayor homogeneidad en la composición relativa de especies. Estos resultados provienen de datos in situ, mientras que los resultados previamente reportados provienen de estadísticas de lances por puerto. En consecuencia, el

  10. Elucidating dynamic responses of North Pacific fish populations to climatic forcing: Influence of life-history strategy

    Science.gov (United States)

    Yatsu, A.; Aydin, K. Y.; King, J. R.; McFarlane, G. A.; Chiba, S.; Tadokoro, K.; Kaeriyama, M.; Watanabe, Y.

    2008-05-01

    In order to explore mechanistic linkages between low-frequency ocean/climate variability, and fish population responses, we undertook comparative studies of time-series of recruitment-related productivity and the biomass levels of fish stocks representing five life-history strategies in the northern North Pacific between the 1950s and the present. We selected seven species: Japanese sardine ( Sardinopus melanostictus) and California sardine ( Sardinopus sagax) (opportunistic strategists), walleye pollock ( Theragra chalcogramma, intermediate strategist), pink salmon ( Oncorhynchus gorbuscha, salmonic strategist), sablefish ( Anoplopoma fimbria) and Pacific halibut ( Hippoglossus stenolepis) (periodic strategists) and spiny dogfish ( Squalus acanthias, equilibrium strategist). The responses in terms of productivity of sardine, pink salmon, sablefish and halibut to climatic regime shifts were generally immediate, delayed, or no substantial responses depending on the particular regime shift year and fish stock (population). In walleye pollock, there were some periods of high productivity and low productivity, but not coincidental to climatic regime shifts, likely due to indirect climate forcing impacts on both bottom-up and top-down processes. Biomass of zooplankton and all fish stocks examined, except for spiny dogfish whose data were limited, indicated a decadal pattern with the most gradual changes in periodic strategists and most intensive and rapid changes in opportunistic strategists. Responses of sardine productivity to regime shifts were the most intense, probably due to the absence of density-dependent effects and the availability of refuges from predators when sardine biomass was extremely low. Spiny dogfish were least affected by environmental variability. Conversely, spiny dogfish are likely to withstand only modest harvest rates due to their very low intrinsic rate of increase. Thus, each life-history strategy type had a unique response to climatic

  11. A LATE SANTONIAN FISH-FAUNA FROM THE EUTAW FORMATION OF ALABAMA RECONSTRUCTED FROM OTOLITHS

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    WERNER W. SCHWARZHANS

    2018-01-01

    Full Text Available The otoliths described here from the Late Santonian of the Eutaw Formation of Alabama, represent one of the earliest association of teleost otoliths known from North America and it is remarkable for its good preservation and species diversity. They were collected by the late C.K. Lamber in 1969 from a road cut on the Hurtsboro-Marvyn highway south of Marvyn in Russell County, eastern Alabama. It contains 18 taxa based on sagittae otoliths, of which 14 are identifiable to the species level, 10 species are new to science and five new genera. The new otolith-based genera are: Allogenartina n. gen. (Stomiiformes family indet., Pseudotrichiurus n. gen. (Aulopiformes family indet., Eutawichthys n. gen. (Beryciformes family indet., Cowetaichthys n. gen. (Polymixiidae and Vox n. gen. (Teleostei family indet.; the new species are: Elops eutawanus n. sp., Genartina cretacea n. sp., Allogenartina muscogeei n. sp., Pseudotrichiurus sagax n. sp., Apateodus? assisi n. sp., Eutawichthys compressus n. sp., Eutawichthys stringeri n. sp., Cowetaichthys alabamae n. sp., Cowetaichthys lamberi n. sp. and Vox thlotlo n. sp. In addition, 8 different morphologies are recognized based on lapilli otoliths, which however cannot be identified to a distinct taxonomic level except for a species of the Ariidae. Two taxa can be related to otoliths recently recorded in situ, pertaining to the genera Osmeroides and Apateodus. The otolith association bears much similarity with those of the Campanian to Maastrichtian of the USA described previously as indicated by the dominance of otoliths of the genera Eutawichthys and Osmeroides. Differences with those faunas are on the species level as well as in the accessory components. The abundance of otoliths of the albuliforms (Osmeroides, putative stomiiforms (Allogenartina, beryciform (Eutawichthys and polymixiids (Cowetaichthys characterizes a rather stable faunal composition through the entire Late Cretaceous of locations studied in

  12. RÉGIMEN ALIMENTARIO DE SIETE ESPECIES ÍCTICAS EN EL EMBALSE DE LA HIDROELÉCTRICA URRÁ (CÓRDOBA, COLOMBIA

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    V.J. Atencio-García

    2005-12-01

    Full Text Available El objeto del estudio fue evaluar el régimen alimentario de siete especies de peces que se han establecidoen el embalse de la Hidroeléctrica Urrá (HU. Se analizaron 453 estómagos, distribuidos así: 115 deperico (Tracheolypterus badeli cf, 111 de cacucho (Panaque gibbosus, 108 de yalúa (Cyphocharaxmagdalenae, 89 de mojarra amarilla (Caquetaia kraussii , 11 de moncholo (Hoplias malabaricus, 10 debarbul ( Pimelodus clarias y 9 de doncella ( Ageneoisus pardales . Los contenidos estomacales se evaluaronmediante frecuencia de ocurrencia (FO, frecuencia numérica (FN y el método gravimétrico (G. Sedeterminó la importancia de cada presa mediante el índice de categorización de presa (ICP y lasuperposición de dietas se analizó mediante el Índice de Morosita (IM. La distribución porcentual de loscontenidos estomacales de la yalúa mostró que el 95.5% correspondió al ítem detritus y el restante 4.5%a microlagas (Clorofitas y Bacillariofitas y protozoarios/rotíferos. La dieta del cacucho la conformaron enun 70.9% microalgas (Cianofitas, Clorofitas y Bacilariofitas y protozoarios/rotíferos y el restante 29.1%correspondieron al ítem detritus. Barbul (FO = 50%, FN = 46.2% y perico se alimentaron principalmentede insectos (FO = 73.9%, FN = 86.4%. La mojarra amarilla (FO = 87.1%, FN = 83.3%, doncella(FO = 92.3%, FN = 92.0% y moncholo (FO = 90.9%, FN = 90.9% prefieren peces como cachanita(Roeboides dayi y sardinas ( Astianax sp. Los resultados sugieren que yalúa es detritívoro iliófago, cacuchoes detritívoro, perico y barbul son carnívoros insectívoros y doncella, moncholo y mojarra amarilla soncarnívoros piscívoros.

  13. Optimization of supercritical carbon dioxide (CO2 extraction of sardine (Sardinella lemuru Bleeker oil using response surface methodology (RSM

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    Gedi, M. A.

    2015-06-01

    Full Text Available Oil was extracted from freeze-dried sardine (Sardinella lemur fillets using supercritical carbon dioxide (SC-CO2 and a few milliliters of ethanol were optimized with response surface methodology (RSM. The impact of extraction pressure (200–400 bars and temperature (40–70 °C were studied on the total extraction yields, ratios of Eicosapentaenoic acid (EPA and Docosahexaenoic acid (DHA. The results were compared with those of Soxhlet and modified Kinsella methods (MKM. The oils obtained using the SC-CO2 and MKM methods were significantly (P El aceite se extrae de filetes de sardinas (Sardinella lemur liofilizando, mediante dióxido de carbono supercrítico (SC-CO2 y unos mililitros de etanol, optimizándose mediante la metodología de superficie de respuesta (RSM. Se ha estudiado la influencia de la presión de extracción (200–400 bars y la temperatura (40–70 °C sobre los rendimientos de extracción total, y sobre las relaciones de ácido eicosapentaenoico (EPA y ácido docosahexaenoico (DHA. Los resultados se compararon con los obtenidos mediante extracción con Soxhlet y el método de Kinsella modificado (MKM. Los aceites obtenidos mediante SC-CO2 y métodos MKM fueron significativamente (P < 0.05 superiores en rendimientos de aceite (8,04% y 6,83%, EPA (5,43% y 5,45% y DHA (18,76% y 18,54%, respectivamente, en comparación con rendimientos mediante Soxhlet (5,10%, EPA (2,17% y DHA (06,46%. De las dos variables independientes, la presión tuvo un efecto crítico sobre el rendimiento, mientras que los porcentajes de EPA y DHA estuvieron notablemente influenciados por la temperatura. Los valores óptimos fueron para una presión de 328 bar y una temperatura de 40 °C, y sus correspondientes respuestas fueron 7,20%, 5,68% y 20,09% para el rendimiento, EPA y DHA, respectivamente. Los valores experimentales de este estudio fueron los previstos y son comparables razonablemente con sus homólogos.

  14. Temperature and food-mediated variability of European Atlantic sardine recruitment

    Science.gov (United States)

    Garrido, Susana; Silva, Alexandra; Marques, Vitor; Figueiredo, Ivone; Bryère, Philippe; Mangin, Antoine; Santos, A. Miguel P.

    2017-12-01

    The influence of the environmental conditions during larval development on the resulting recruitment strength was investigated for European sardine (Sardina pilchardus) at Atlanto-Iberian waters. Satellite-derived Sea Surface Temperature (SST) and Chlorophyll-a concentration (Chla) data from the previous spawning seasons (January to March/April and October to December of the previous year) were related to recruitment success data in the main recruitment hotspots. Recruitment data was taken from yearly acoustic scientific cruises and from the ICES recruitment index estimated by an age-structured model for the entire stock. A linear discriminant analysis model using SST, Chla, and the abundance of spawners during the spawning season identified years of high and low recruitment for all the recruitment hotspots with an accuracy of ≥79%. In general, high recruitment years were associated with high Chla and low SST, although the most important variables to discriminate between the groups were area-specific. High recruitment years were mostly related to high food availability (Chla), particularly during the last quarter of the previous year. In Western Iberia and in the Gulf of Cadiz, high recruitment years were also associated to lower SST, whereas in the Bay of Biscay, where SST during the winter was generally below the optimal range ≈11-12 °C for sardine larval development, higher recruitment was associated with high SST. For ICES data of the southern European sardine stock, lower SST and higher Chla during the last quarter of the previous year were associated with high recruitment years and SST alone was able to discriminate between the two recruitment groups with 73% accuracy. Although the time-series of available data are still small, these significant relationships are consistent with field and laboratory studies relating larval growth and mortality with main environmental drivers. These relationships should be further investigated in the following years to

  15. Toxic metals in tissues of fishes from the Black Sea and associated human health risk exposure.

    Science.gov (United States)

    Plavan, Gabriel; Jitar, Oana; Teodosiu, Carmen; Nicoara, Mircea; Micu, Dragos; Strungaru, Stefan-Adrian

    2017-03-01

    The anthropogenic activities in the Black Sea area are responsible for toxic metal contamination of sea food products. In this study, several toxic metals: cadmium, lead, nickel, chromium, and copper were quantified in different tissues (digestive tract, muscle, skeleton, skin) of nine fish species (Neogobius melanostomus, Belone belone, Solea solea, Trachurus mediterraneus ponticus, Sardina pilchardus, Engraulis encrasicolus, Pomatomus saltatrix, Sprattus sprattus, Scorpaena porcus) by using atomic absorption spectrometer with a high-resolution continuum source and graphite furnace technique (HR-CS GF-AAS), and the risk of fish meat consumption by the young human population was evaluated. These metals are used in high amounts in industries located near the coastline such as shipyard construction and industrial plants. Toxic metal accumulation depends on fish feeding behavior, abiotic conditions, metal chemistry, and animal physiology. For instance, cadmium was measured in the muscle of the investigated species and average values of 0.0008-0.0338 mg kg -1 were obtained. The lowest average value of this metal was measured at benthic species N. melanostomus and the highest at the pelagic predator T. mediterraneus ponticus. Generally, the highest metal concentration was measured in the digestive tract that has the role of biofilter for these contaminants. The risk of contamination is significantly reduced by avoiding the consumption of certain fish tissues (digestive tract and skin for copper and skeleton for nickel). An estimation of the dietary metal intake to young consumers was realized for each of the studied species of fish from Romanian, Bulgarian, and Turkish waters, during the period 2001-2014 in order to evaluate the risks of chronic exposure in time due to metal toxicity. This estimation is important for the prevention of chronic exposure due to metal toxicity. Food exposure to studied metals showed a negative trend for Romania, Turkey, and Bulgaria based

  16. Trol ve uzatma ağları ile İzmir körfezinden yakalanan dil (Solea solea balığının yaşama yüzdesi; kültür şartlarına adaptasyonu ve beslenme davranışı.

    Directory of Open Access Journals (Sweden)

    Doç.Dr. Fatih Başaran

    2008-01-01

    Full Text Available Trol ve uzatma ağları ile İzmir körfezinden yakalanan dil (Solea solea balığının yaşama yüzdesi; kültür şartlarına adaptasyonu ve beslenme davranışı. Bu araştırmada, doğal ortamdan yakalanan dil balığının (Solea solea, kültür şartlarına adaptasyonu ve beslenme davranışı incelenmiştir. Dil balıkları, 2007 Mart-Nisan döneminde, İzmir Körfezi’nden trol ve uzatma ağlarıyla yakalanmıştır. 270 adet dil balığının ön adaptasyonu sırasında, ilk beş gün boyunca, karanlık ortamda antibiyotik (100 ppm fruzolidon ilavesi, 60 dak/gün uygulaması gerçekleştirilmiştir. Kültür şartlarında ilk besleme için, kalamar (Loligo vulgaris, boru kurdu (Diopatra neopolitana, kara midye (Mytilus galloprovincialis, sülünes (Solen marginatus, istiridye (Ostrea edulis, japon şapkası (Patella spp., deniz salyangozu (Monodonta turbinata ve taze sardalya (Sardina pilchardus kullanılmıştır. Dil balıkları 0-2 gün içinde beslenmeye başlamıştır ve boru kurdu, en çok tercih ettikleri tür olmuştur. Bir aylık adaptasyon dönemi sonunda, uzatma ağlarıyla yakalanan dil balıklarının yaşama oranının (%58, trol ile yakalananların yaşama oranından (%29 önemli düzeyde yüksek bulunmuştur (p

  17. Profesor Luis López de Mesa. Reminiscencias

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    J. Hernando Ordoñez

    1998-12-01

    ñas.

    Su compleja erudición y profundos conocimientos le imprimieron una personalidad que llevaron a algunos a calificar como incomprensible, abstrusa. Conociéndolo como lo conocí, no puedo compartir tan equivocados conceptos. Quienes así pensaban, estaban reconociendo tácitamente su menoría cultural. (Menoría, de menor. A propósito recuerdo la conferencia que dictó el Profesor en 1946 sobre el origen y la evolución de la vida en el planeta , a la cual tuve el placer de asistir. Se refirió al origen de la vida en el mar hace millones de años y continuó su exposición sobre las diferentes etapas de su evolución, haciendo énfasis en el fenómeno de la adaptación de los primeros vertebrados a la vida terrestre.

    Hizo mención especial del primer pez que intentó hacerlo, etapa que calificó como trascendental para la evolución de las especies. Citó el nombre de este pez en la clasificación, si no recuerdo mal, un Crossopterigio, y, para que se entendiera mejor, dijo que era así como una variedad de sardina. Esta aclaración desató una serie de comentarios diciendo que el Profesor López de Mesa había sostenido que el hombre desciende de la sardina. En rigor científico, pensando en la filogenia y en la evolución en millones de años, el Profesor tenía razón...

  18. EVALUACIÓN POBLACIONAL DEL STOCK EXPLOTABLE DEL COMPLEJO OPISTHONEMA (PISCES: CLUPEIDAE EN EL GOLFO DE NICOYA, COSTA RICA

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    Luis A. Vega Corrales

    2011-07-01

    Full Text Available El género Opisthonema sustenta la pesquería de sardina en Costa Rica. Esta investigación se orientó hacia la evaluación poblacional del stock explotable de esta pesquería en el Golfo de Nicoya. Las muestras mensuales fueron recolectadas desde junio del 2007 hasta mayo del 2008. Se determinó el patrón de reproducción de O. libertate y se estimaron los parámetros de crecimiento de las curvas en longitud del modelo de von Bertalanffy para O. libertate y O. medirastre. Con base en el índice gonadosomático, O. libertate desova intensamente durante la época más calurosa del año, entre febrero y mayo. La talla de primera madurez (TPM50% fue de 18.68 cm de LT. La ecuación de crecimiento de von Bertalanffy estimada para O. libertate fue: Lt= 25.9 [1–exp–1.03(t+0.13] y para O. medirastre: Lt= 32.0 [1–exp–1.10(t+0.15]. El reclutamiento máximo de la pesquería de O. libertate ocurre entre septiembre y noviembre. Esta especie muestra un índice de explotación (E de 0.65 y O. medirastre de 0.55. Se nota una mejoría en el E comparado con estimaciones anteriores. Se recomienda como medida de manejo para esta pesquería ajustar la época de veda y no incrementar el esfuerzo pesquero. The Opisthonema genus supports the sardine fishery in Costa Rica. This research was directed to population assessment of the exploitable stock of this fishery in the Golfo of Nicoya. Monthly samples were collected since June, 2007 until May, 2008. The reproductive pattern of O. libertate were determined and growth parameters of curves in the length of O. libertate and O. medirastre were estimated using the von Bertalanffy model.. Based on the gonadosomatic index, O. libertate spawn intensively during the hottest time of the year, between February and May. The size at first maturity (SFM50% was 18.68 cm T.L. The growth equation of von Bertalanffy was estimated for O. libertate: Tl= 25.9 [1–exp–1.03(t+0.13] and O. medirastre:  Tl= 32.0 [1–exp–1.10(t

  19. Ecophysiological behavior of Caquetaia kraussii (Steindachner, 1878 (Pisces: Cichlidae exposed to different temperatures and salinities

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    M.I. Segnini de Bravo

    2001-03-01

    Full Text Available Tropical river sardine, Caquetaia kraussii, captured from La Aguá lagoon (Sucre State, Venezuela were acclimatized for four weeks at 22, 24, 30 and 32ºC and at 0, 5, 10, 15 and 17 ‰ salinity. To evaluate effects of thermal response to acclimatization level, the fish were transferred suddenly from lower temperatures (22 and 24ºC to higher ones (32 and 30ºC respectively. Then thermal resistance time was measured at the lethal temperature of 40.9ºC for 30 days. We considered that acclimatization process completed when resistance time was stabilized at the new temperature regime. For the saline effect, the concentrations of sodium and potassium were measured in the tissues at each treatment: gills, white muscle, gut and heart. The results showed that thermal tolerance increased rapidly in 3 h with a 6ºC rise in temperature (from 24 to 30ºC and in 24 h with a 10ºC rise (22 to 32ºC. With decreasing temperatures, the acclimatization level reached its lowest in 11 days with a 6ºC decreases (from 30 to 24ºC and in 14 days with a 10ºC decrease (32 to 22ºC. Caquetaia kraussii regulates as much sodium as potassium in gills and white muscle tissues at all salinity levels tested; however, gut and heart tissues showed significantly different regulations among salinities examined.La sardina tropical de río, Caquetaia kraussii, capturada en la laguna La Aguá (Estado Sucre, Venezuela fue aclimatada durante cuatro semanas a la temperatura de 22, 24, 30 y 32ºC y a 0, 5, 10, 15 y 17 ‰ de salinidad. Para evaluar los efectos de respuestas térmicas a los niveles de aclimatación, los peces fueron transferidos abruptamente desde las temperaturas bajas (22 y 24ºC hasta las altas (32 y 30ºC respectivamente. Se midió entonces la resistencia térmica a la temperatura letal de 40.9ºC durante 30 días. Se consideró que los peces habían alcanzado completamente su aclimatación cuando se estabilizaba al nuevo régimen de temperatura. Para el efecto

  20. Distribución del ictioplancton en la Patagonia austral de Chile: potenciales efectos del deshielo de Campos de Hielo Sur Ichthyoplankton distribution in South Patagonia, Chile: potential effects of ice melting from the Southern Ice Field

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    Mauricio F Landaeta

    2011-07-01

    Full Text Available Durante octubre-noviembre de 2009 se realizó un crucero oceanográfico entre 50 y 53°S de Chile austral, en las cercanías del glaciar Campos de Hielo Sur. Las estaciones cercanas al glaciar presentaron baja temperatura (1-3°C y salinidad ( 0,1 ciclos s-1. Los principales taxa del ictioplancton fueron huevos y larvas de sardina fueguina Sprattus fuegensis, pez hacha Maurolicus parvipinnis, Macrouridae y merluza austral Merluccius australis. El desove principal de S. fuegensis (~ 8000 huevos 10 m-2 ocurrió en zonas mezcladas de la plataforma continental adyacente, mientras que el desove de M. parvipinnis ocurrió en canales intermedios asociado a valores intermedios de estabilidad (N~0,06 ciclos s-1. Se observó una nula o baja abundancia de huevos y larvas de peces en las cercanías del glaciar, y la abundancia de huevos de M. parvipinnis estuvo relacionada positivamente con la temperatura y salinidad de la columna de agua y negativamente con la estabilidad de la columna de agua. Además, hubo una relación negativa entre la densidad del agua de mar y el diámetro de los huevos de S. fuegensis. La relación entre deshielo e ictioplancton podría tener consecuencias en el transporte advectivo y mortalidad masiva de huevos y larvas de peces y el acople pelágico-bentónico en la Patagonia austral de Chile. Como el cambio climático global ha incrementado los deshielos de glaciares en latitudes altas, y el aumento del ingreso de aguas de baja temperatura y salinidad podría tener consecuencias en el ictioplancton de la Patagonia chilena.In October-November 2009, an oceanographic survey was carried out between 50 and 53°S off southern Chile, near the Southern Ice Field. The stations near the glacier showed low temperatures (1-3°C and salinity ( 0.1 cycles s-1. Main ichthyoplankton taxa were eggs and larvae of southern sprat Sprattus fuegensis, lightfish Maurolicus parvipinnis, Macrouridae, and southern hake Merluccius australis. The main

  1. Sondeo ecológico rápido de las comunidades de peces tropicales en un área de explotación minera en Costa Rica

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    Mario Espinoza Mendiola

    2008-12-01

    Full Text Available El impacto de las minerías de oro ha generado una gran preocupación por el deterioro de los hábitats acuáticos y la fragmentación de los sistemas naturales. Las perturbaciones antropogénicas sobre la estructura y heterogeneidad del sistema pueden influir en la estabilidad de las comunidades acuáticas. Sondeos ecológicos rápidos (1996, 2002, 2007 fueron empleados para determinar la estructura, composición y distribución de las comunidades de peces tropicales en varios ríos y quebradas del área de una minería de oro en el Cerro Crucitas, Costa Rica. Además, la composición de especies y abundancia relativa se relacionó con la estructura del hábitat. Se registró un total de 35 especies, de las cuales la sardina Astyanax aeneus (Characidae y la olomina Alfaro cultratus (Poeciliidae fueron las especies más abundantes (71%. La mayor riqueza de especies se observó en el Caño Crucitas (s = 19 y la quebrada Minas (s = 18. Se encontró una gran variación en la estructura y composición de las comunidades de peces, principalmente, en el río Infiernillo y Minas (λ = 0.0, F132, 66 = 2.24, p Rapid ecological assessment of tropical fish communities in a gold mine area of Costa Rica. Gold mining impacts have generated a great concern regarding aquatic systems and habitat fragmentation. Anthropogenic disturbances on the structure and heterogeneity of a system can have an important effect on aquatic community stability. Ecological rapid assessments (1996, 2002, and 2007 were employed to determine the structure, composition and distribution of tropical fish communities in several rivers and smaller creeks from a gold mining area in Cerro Crucitas, Costa Rica. In addition, species composition and relative abundance were related with habitat structure. A total of 35 species were registered, among which sardine Astyanax aeneus (Characidae and livebearer Alfaro cultratus (Poeciliidae were the most abundant fish (71%. The highest species