WorldWideScience

Sample records for electric fish brachyhypopomus

  1. Simulated predator stimuli reduce brain cell proliferation in two electric fish species, Brachyhypopomus gauderio and Apteronotus leptorhynchus.

    Science.gov (United States)

    Dunlap, Kent D; Keane, Geoffrey; Ragazzi, Michael; Lasky, Elise; Salazar, Vielka L

    2017-07-01

    The brain structure of many animals is influenced by their predators, but the cellular processes underlying this brain plasticity are not well understood. Previous studies showed that electric fish ( Brachyhypopomus occidentalis ) naturally exposed to high predator ( Rhamdia quelen ) density and tail injury had reduced brain cell proliferation compared with individuals facing few predators and those with intact tails. However, these field studies described only correlations between predator exposure and cell proliferation. Here, we used a congener Brachyhypopomus gauderio and another electric fish Apteronotus leptorhynchus to experimentally test the hypothesis that exposure to a predator stimulus and tail injury causes alterations in brain cell proliferation. To simulate predator exposure, we either amputated the tail followed by short-term (1 day) or long-term (17-18 days) recovery or repeatedly chased intact fish with a plastic rod over a 7 day period. We measured cell proliferation (PCNA+ cell density) in the telencephalon and diencephalon, and plasma cortisol, which commonly mediates stress-induced changes in brain cell proliferation. In both species, either tail amputation or simulated predator chase decreased cell proliferation in the telencephalon in a manner resembling the effect of predators in the field. In A. leptorhynchus , cell proliferation decreased drastically in the short term after tail amputation and partially rebounded after long-term recovery. In B. gauderio , tail amputation elevated cortisol levels, but repeated chasing had no effect. In A. leptorhynchus , tail amputation elevated cortisol levels in the short term but not in the long term. Thus, predator stimuli can cause reductions in brain cell proliferation, but the role of cortisol is not clear. © 2017. Published by The Company of Biologists Ltd.

  2. Phylogenetic Systematics, Biogeography, and Ecology of the Electric Fish Genus Brachyhypopomus (Ostariophysi: Gymnotiformes.

    Directory of Open Access Journals (Sweden)

    William G R Crampton

    Full Text Available A species-level phylogenetic reconstruction of the Neotropical bluntnose knifefish genus Brachyhypopomus (Gymnotiformes, Hypopomidae is presented, based on 60 morphological characters, approximately 1100 base pairs of the mitochondrial cytb gene, and approximately 1000 base pairs of the nuclear rag2 gene. The phylogeny includes 28 species of Brachyhypopomus and nine outgroup species from nine other gymnotiform genera, including seven in the superfamily Rhamphichthyoidea (Hypopomidae and Rhamphichthyidae. Parsimony and Bayesian total evidence phylogenetic analyses confirm the monophyly of the genus, and identify nine robust species groups. Homoplastic osteological characters associated with diminutive body size and occurrence in small stream habitats, including loss of squamation and simplifications of the skeleton, appear to mislead a phylogenetic analysis based on morphological characters alone-resulting in the incorrect placing of Microsternarchus + Racenisia in a position deeply nested within Brachyhypopomus. Consideration of geographical distribution in light of the total evidence phylogeny indicates an origin for Brachyhypopomus in Greater Amazonia (the superbasin comprising the Amazon, Orinoco and major Guiana drainages, with subsequent dispersal and vicariance in peripheral basins, including the La Plata, the São Francisco, and trans-Andean basins of northwest South America and Central America. The ancestral habitat of Brachyhypopomus likely resembled the normoxic, low-conductivity terra firme stream system occupied by many extant species, and the genus has subsequently occupied a wide range of terra firme and floodplain habitats including low- and high-conductivity systems, and normoxic and hypoxic systems. Adaptations for impedance matching to high conductivity, and/or for air breathing in hypoxic systems have attended these habitat transitions. Several species of Brachyhypopomus are eurytopic with respect to habitat occupancy and

  3. Reproduction and feeding of the electric fish Brachyhypopomus gauderio (Gymnotiformes: Hypopomidae and the discussion of a life history pattern for gymnotiforms from high latitudes.

    Directory of Open Access Journals (Sweden)

    Julia Giora

    Full Text Available The reproductive biology and feeding habits of the electric fish Brachyhypopomus gauderio were studied. The species has seasonal reproductive behavior, with breeding occurring during the Southern Hemisphere spring and summer, and having a positive relation with the photoperiod variation. Brachyhypopomus gauderio was defined as a fractional spawner, with low relative fecundity and high first maturation size. Sexual dimorphism was registered, males undergoing hypertrophy of the distal portion of caudal filament. The results on reproductive biology herein obtained are in agreement with data concerning gymnotiforms from Southern Brazil and Uruguay, pointing to an ecological pattern for the species from high latitudes, differing from species with tropical distribution. According to the analysis of the food items, B. gauderio feed mainly on autochthonous insects, likewise the other gymnotiforms previously investigated, leading to conclude that there is no variation on the diet of the species of the order related to climatic conditions or even to habitat of occurrence.

  4. A taxonomic revision of the Neotropical electric fish genus Brachyhypopomus (Ostariophysi: Gymnotiformes: Hypopomidae, with descriptions of 15 new species

    Directory of Open Access Journals (Sweden)

    William G. R. Crampton

    Full Text Available ABSTRACT The bluntnose knifefish genus BrachyhypopomusMago-Leccia, 1994, is diagnosed from other Rhamphichthyoidea (Rhamphichthyidae + Hypopomidae by the presence of a disk-like ossification in the anterior portion of the palatoquadrate, and by the following external characters: short snout, 18.7-32.6% of head length (vs. 33.3-68.6% in Hypopomus, Gymnorhamphichthys, Iracema, and Rhamphichthys, absence of a paired accessory electric organ in the mental or humeral region (vs. presence in Hypopygus and Steatogenys, presence of 3-4 pectoral proximal radials (vs. 5 in Akawaio, presence of the antorbital + infraorbital, and the preopercular cephalic lateral line canal bones (vs. absence in Racenisia. Brachyhypopomus cannot be diagnosed unambiguously from Microsternarchus or from Procerusternarchus on the basis of external characters alone. Brachyhypopomus comprises 28 species. Here we describe 15 new species, and provide redescriptions of all 13 previously described species, based on meristic, morphometric, and other morphological characters. We include notes on ecology and natural history for each species, and provide regional dichotomous keys and distribution maps, based on the examination of 12,279 specimens from 2,787 museum lots. A lectotype is designated for Brachyhypopomus pinnicaudatus (Hopkins, Comfort, Bastian & Bass, 1990. Brachyhypopomus species are abundant in shallow lentic and slow-flowing freshwater habitats from southern Costa Rica and northern Venezuela to Uruguay and northern Argentina. Species diversity is highest in Greater Amazonia, where 20 species occur: B. alberti, new species, B. arrayae, new species, and B. cunia, new species, in the upper rio Madeira drainage; B. batesi, new species, in the central Amazon and rio Negro; B. beebei, B. brevirostris, B. regani, new species, B. sullivani, new species, and B. walteri, widespread through the Amazon and Orinoco basins and the Guianas; B. belindae, new species, in the central

  5. Two new species and a new subgenus of toothed Brachyhypopomus electric knifefishes (Gymnotiformes, Hypopomidae) from the central Amazon and considerations pertaining to the evolution of a monophasic electric organ discharge.

    Science.gov (United States)

    Sullivan, John P; Zuanon, Jansen; Cox Fernandes, Cristina

    2013-01-01

    We describe two new, closely related species of toothed Brachyhypopomus (Hypopomidae: Gymnotiformes: Teleostei) from the central Amazon basin and create a new subgenus for them. Odontohypopomus, new subgenus of Brachyhypopomus, is diagnosed by (1) small teeth present on premaxillae; (2) medialmost two branchiostegal rays thin with blades oriented more vertically than remaining three rays; (3) background color in life (and to lesser extent in preservation) distinctly yellowish with head and sides peppered with small, widely spaced, very dark brown stellate chromatophores that greatly contrast with light background coloration; (4) a dark blotch or bar of subcutaneous pigment below the eye; (5) electric organ discharge waveform of very long duration (head-positive phase approx. 2 milliseconds or longer, head-negative phase shorter or absent) and slow pulse repetition rate (3-16 Hz). The type species of the new subgenus, Brachyhypopomus (Odontohypopomus) walteri sp. n., is diagnosed by the following additional character states: (1) subcutaneous dark pigment at base of orbit particularly prominent, (2) body semi-translucent and nearly bright yellow background coloration in life, (3) a biphasic electric organ discharge (EOD) waveform of very long duration (between 3.5 and 4 milliseconds at 25° C) with head-positive first phase significantly longer than second head-negative phase in both sexes. Brachyhypopomus (Odontohypopomus) bennetti sp. n. is diagnosed by two character states in addition to those used to diagnose the subgenus Odontohypopomus: (1) a deep electric organ, visible as large semi-transparent area, occupying approximately 14-17% body depth directly posterior to the abdominal cavity in combination with a short, but deep, caudal filament, and (2) a monophasic, head-positive EOD waveform, approximately 2.1 milliseconds in duration in both sexes. These are the only described rhamphichthyoid gymnotiforms with oral teeth, and Brachyhypopomus bennetti is the first

  6. X1X1X2X2/X1X2Y sex chromosome systems in the Neotropical Gymnotiformes electric fish of the genus Brachyhypopomus

    Directory of Open Access Journals (Sweden)

    Adauto Lima Cardoso

    2015-06-01

    Full Text Available Several types of sex chromosome systems have been recorded among Gymnotiformes, including male and female heterogamety, simple and multiple sex chromosomes, and different mechanisms of origin and evolution. The X1X1X2X2/X1X2Y systems identified in three species of this order are considered homoplasic for the group. In the genus Brachyhypopomus, only B. gauderio presented this type of system. Herein we describe the karyotypes of Brachyhypopomus pinnicaudatus and B. n. sp. FLAV, which have an X1X1X2X2/X1X2Y sex chromosome system that evolved via fusion between an autosome and the Y chromosome. The morphology of the chromosomes and the meiotic pairing suggest that the sex chromosomes of B. gauderio and B. pinnicaudatus have a common origin, whereas in B . n. sp. FLAV the sex chromosome system evolved independently. However, we cannot discard the possibility of common origin followed by distinct processes of differentiation. The identification of two new karyotypes with an X1X1X2X2/X1X2Y sex chromosome system in Gymnotiformes makes it the most common among the karyotyped species of the group. Comparisons of these karyotypes and the evolutionary history of the taxa indicate independent origins for their sex chromosomes systems. The recurrent emergence of the X1X1X2X2/X1X2Y system may represent sex chromosomes turnover events in Gymnotiformes.

  7. Food restriction promotes signaling effort in response to social challenge in a short-lived electric fish.

    Science.gov (United States)

    Gavassa, Sat; Stoddard, Philip K

    2012-09-01

    Vertebrates exposed to stressful conditions release glucocorticoids to sustain energy expenditure. In most species elevated glucocorticoids inhibit reproduction. However individuals with limited remaining reproductive opportunities cannot afford to forgo reproduction and should resist glucocorticoid-mediated inhibition of reproductive behavior. The electric fish Brachyhypopomus gauderio has a single breeding season in its lifetime, thus we expect males to resist glucocorticoid-mediated inhibition of their sexual advertisement signals. We studied stress resistance in male B. gauderio (i) by examining the effect of exogenous cortisol administration on the signal waveform and (ii) by investigating the effect of food limitation on androgen and cortisol levels, the amplitude of the electric signal waveform, the responsiveness of the electric signal waveform to social challenge, and the amount of feeding activity. Exogenous cortisol administration did reduce signal amplitude and pulse duration, but endogenous cortisol levels did not rise with food limitation or social challenge. Despite food limitation, males responded to social challenges by further increasing androgen levels and enhancing the amplitude and duration of their electric signal waveforms. Food-restricted males increased androgen levels and signal pulse duration more than males fed ad libitum. Socially challenged fish increased food consumption, probably to compensate for their elevated energy expenditure. Previous studies showed that socially challenged males of this species simultaneously elevate testosterone and cortisol in proportion to signal amplitude. Thus, B. gauderio appears to protect its cortisol-sensitive electric advertisement signal by increasing food intake, limiting cortisol release, and offsetting signal reduction from cortisol with signal-enhancing androgens. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Electrical burns in sports fishing: a case report.

    Science.gov (United States)

    Valença-Filipe, R; Egipto, P; Horta, R; Braga, J M; Costa, J; Silva, A

    2014-11-01

    Electrical burns are among the most devastating types of burns, with wide-ranging injuries. They can sometimes occur in the context of fishing, usually involving high voltages. The authors present the case of a 59-year-old-man who suffered a sports accident during a fishing competition, with the formation of an electrical arc due to proximity of the fishing rod and high voltage cables. He presented burns affecting 3% of TBSA, third degree deep burns on trunk and left hand; no signs of cardiac injury. He was admitted to our Burn Unit for monitoring, care dressing and surgical treatment; complete wound healing was achieved after 24 days. Due to its relatively small share among burns, published data on electrical injuries and fishing remain scarce, and differ in patient collectives due to infrastructural or environmental differences. The authors are not aware of published specific reports on electrical burns in sports fishing practice, like the case here presented. The authors want to alert for potential medical, social and economic consequences of this type of sports accidents that could be entirely avoidable with some preventive measures. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

  9. ASSESSMENT OF THE ELECTRIC POWER QUALITY ON THE POLISH FISHING BOATS

    Directory of Open Access Journals (Sweden)

    Dariusz TARNAPOWICZ

    2015-07-01

    Full Text Available Power quality is an important problem for electrical systems. Electricity receivers should operate at nominal conditions. Each deviation from nominal values may cause the malfunction of electrical devices, decreasing their durability and per-manently damage the appliance. The importance of electric power quality for technical systems and individual electrical devices on fishing boats is fundamental. Utilization of equipment powered by electrical energy with a reduced quality resulting in economical losses and the treat to the screw's safety. Researches of the electrical energy's quality were carried out almost any type of fishing boats. This article presents the results of researches concerning the quality of electrical energy performed on a representative type of fishing boats. It shortly evaluates the results of tests and suggests solutions to improve the power quality parameters.

  10. Feeding response of sport fish after electrical immobilization, chemical sedation, or both

    Science.gov (United States)

    Meinertz, Jeffery R.; Fredricks, Kim T.; Ambrose, Ryan D.; Jackan, Leanna M.; Wise, Jeremy K.

    2012-01-01

    Fishery managers frequently capture wild fish for a variety of fishery management activities. Though some activities can be accomplished without immobilizing the fish, others are accomplished more readily, humanely, and safely (for both the handler and the fish) when fish are immobilized by physical (e.g., electrical immobilization) or chemical sedation. A concern regarding the use of chemical sedatives is that chemical residues may remain in the fillet tissue after the fish recovers from sedation. If those residues are harmful to humans, there is some risk that a postsedated fish released to public waters may be caught and consumed by an angler. To characterize this risk, a series of four trials were conducted. Three trials assessed feeding activity after hatchery-reared fish were electrically immobilized, chemically sedated, or both, and one trial assessed the likelihood of an angler catching a wild fish that had been electrically immobilized and chemically sedated. Results from the first trial indicated that the feeding activity of laboratory habituated fish was variable among and within species after electrical immobilization, chemical sedation, or both. Results from the second trial indicated that the resumption of feeding activity was rapid after being mildly sedated for 45 min. Results from the third trial indicated that the feeding activity of outdoor, hatchery-reared fish was relatively aggressive after fish had been chemically sedated. Results from the fourth trial indicated that the probability of capturing wild fish in a more natural environment by angling after fish had been electrically immobilized and chemically sedated is not likely, i.e., in a group of five fish caught, 3 out of 100 times one would be a fish that had been sedated.

  11. Neotropical electric fishes (Gymnotiformes as model organisms for bioassays

    Directory of Open Access Journals (Sweden)

    Milena Ferreira

    2015-04-01

    Full Text Available Electric fishes (Gymnotiformes inhabit Central and South America and form a relatively large group with more than 200 species. Besides a taxonomic challenge due to their still unresolved systematic, wide distribution and the variety of habitats they occupy, these fishes have been intensively studied due to their peculiar use of bioelectricity for electrolocation and communication. Conventional analysis of cells, tissues and organs have been complemented with the studies on the electric organ discharges of these fishes. This review compiles the results of 13 bioassays developed during the last 50 years, which used the quickness, low costs and functionality of the bioelectric data collection of Gymnotiformes to evaluate the effects of environmental contaminants and neuroactive drugs.

  12. Underwater electric field detection system based on weakly electric fish

    Science.gov (United States)

    Xue, Wei; Wang, Tianyu; Wang, Qi

    2018-04-01

    Weakly electric fish sense their surroundings in complete darkness by their active electric field detection system. However, due to the insufficient detection capacity of the electric field, the detection distance is not enough, and the detection accuracy is not high. In this paper, a method of underwater detection based on rotating current field theory is proposed to improve the performance of underwater electric field detection system. First of all, we built underwater detection system based on the theory of the spin current field mathematical model with the help of the results of previous researchers. Then we completed the principle prototype and finished the metal objects in the water environment detection experiments, laid the foundation for the further experiments.

  13. The active electric sense of weakly electric fish: from electric organ discharge to sensory processing and behaviour

    Directory of Open Access Journals (Sweden)

    Krahe Rüdiger

    2016-01-01

    Full Text Available Sensory systems have been shaped by evolution to extract information that is relevant for decision making. In order to understand the mechanisms used by sensory systems for filtering the incoming stream of sensory input, it is important to have a quantitative understanding of the natural sensory scenes that are to be processed. Weakly electric fish lead a rather cryptic nocturnal life in often turbid tropical rainforest streams. They produce electric discharges and sense perturbations of their selfgenerated electric field for prey detection and navigation, and also use their active sense for communication in the context of courtship and aggression. The fact that they produce their electric signals throughout day and night permits the use of electrode arrays to track the movements of multiple individual fish and monitor their communication interactions, thus offering a window into their electrosensory world. This approach yields unprecedented access to information on the biology of these fishes and also on the statistical properties of the sensory scenes that are to be processed by their electrosensory system. The electrosensory system shares many organizational features with other sensory systems, in particular, the use of multiple topographic maps. In fact, the sensory surface (the skin is represented in three parallel maps in the hindbrain, with each map covering the receptor organ array with six different cell types that project to the next higher level of processing. Thus, the electroreceptive body surface is represented a total of 18 times in the hindbrain, with each representation having its specific filter properties and degree of response plasticity. Thus, the access to the sensory world of these fish as well as the manifold filtering of the sensory input makes these fish an excellent model system for exploring the cell-intrinsic and network characteristics underlying the extraction of behaviourally relevant sensory information.

  14. High-resolution behavioral mapping of electric fishes in Amazonian habitats.

    Science.gov (United States)

    Madhav, Manu S; Jayakumar, Ravikrishnan P; Demir, Alican; Stamper, Sarah A; Fortune, Eric S; Cowan, Noah J

    2018-04-11

    The study of animal behavior has been revolutionized by sophisticated methodologies that identify and track individuals in video recordings. Video recording of behavior, however, is challenging for many species and habitats including fishes that live in turbid water. Here we present a methodology for identifying and localizing weakly electric fishes on the centimeter scale with subsecond temporal resolution based solely on the electric signals generated by each individual. These signals are recorded with a grid of electrodes and analyzed using a two-part algorithm that identifies the signals from each individual fish and then estimates the position and orientation of each fish using Bayesian inference. Interestingly, because this system involves eavesdropping on electrocommunication signals, it permits monitoring of complex social and physical interactions in the wild. This approach has potential for large-scale non-invasive monitoring of aquatic habitats in the Amazon basin and other tropical freshwater systems.

  15. Mechano-electric feedback in the fish heart.

    Directory of Open Access Journals (Sweden)

    Simon M Patrick

    2010-05-01

    Full Text Available Mechanoelectric feedback (MEF describes the modulation of electrical activity by mechanical activity. This may occur via the activation of mechanosensitive ion channels (MSCs. MEF has not previously been investigated in fish ventricular tissue even though fish can greatly increase ventricular end diastolic volume during exercise which should therefore provide a powerful mechanical stimulus for MEF.When the ventricles of extrinsically paced, isolated working trout hearts were dilated by increasing afterload, monophasic action potential (MAP duration was significantly shortened at 25% repolarisation, unaltered at 50% repolarisation and significantly lengthened at 90% repolarisation. This observation is consistent with the activation of cationic non-selective MSCs (MSC(NSs. We then cloned the trout ortholog of TRPC1, a candidate MSC(NS and confirmed its presence in the trout heart.Our results have validated the use of MAP technology for the fish heart and suggest that, in common with amphibians and mammals, MEF operates in fish ventricular myocardium, possibly via the activation of mechanosensitive TRPC1 ion channels.

  16. Electrical localization of weakly electric fish using neural networks

    International Nuclear Information System (INIS)

    Kiar, Greg; Mamatjan, Yasin; Adler, Andy; Jun, James; Maler, Len

    2013-01-01

    Weakly Electric Fish (WEF) emit an Electric Organ Discharge (EOD), which travels through the surrounding water and enables WEF to locate nearby objects or to communicate between individuals. Previous tracking of WEF has been conducted using infrared (IR) cameras and subsequent image processing. The limitation of visual tracking is its relatively low frame-rate and lack of reliability when visually obstructed. Thus, there is a need for reliable monitoring of WEF location and behaviour. The objective of this study is to provide an alternative and non-invasive means of tracking WEF in real-time using neural networks (NN). This study was carried out in three stages. First stage was to recreate voltage distributions by simulating the WEF using EIDORS and finite element method (FEM) modelling. Second stage was to validate the model using phantom data acquired from an Electrical Impedance Tomography (EIT) based system, including a phantom fish and tank. In the third stage, the measurement data was acquired using a restrained WEF within a tank. We trained the NN based on the voltage distributions for different locations of the WEF. With networks trained on the acquired data, we tracked new locations of the WEF and observed the movement patterns. The results showed a strong correlation between expected and calculated values of WEF position in one dimension, yielding a high spatial resolution within 1 cm and 10 times higher temporal resolution than IR cameras. Thus, the developed approach could be used as a practical method to non-invasively monitor the WEF in real-time.

  17. Fish protection at steam-electric power plants: alternative screening devices

    International Nuclear Information System (INIS)

    Cannon, J.B.

    1978-01-01

    Since the enactment of the Federal Water Pollution Control Act Amendments of 1972, very few innovations have surfaced that advance the state of intake technology for fish protection at steam-electric power plants. After careful examination of basic hydrology, hydraulics, and ecology of the source water body is completed and after a suitable location for the intake is established, the design process reduces to the development of proper screening techniques and to the provision of a means of preventing resident and migratory species from entering the intake structure. As a result of this design process, three basic fish protection concepts have evolved: fish deterrence, fish collection and removal, and fish diversion. Intake screening devices that protect fish are discussed

  18. Inter-calibration of three electric fishing techniques to estimate 0+ juvenile fish densities on sandy river beaches

    Czech Academy of Sciences Publication Activity Database

    Janáč, Michal; Jurajda, Pavel

    2005-01-01

    Roč. 12, č. 3 (2005), s. 161-167 ISSN 0969-997X R&D Projects: GA AV ČR(CZ) IAB6093106; GA ČR(CZ) GA524/02/0924 Institutional research plan: CEZ:AV0Z60930519 Keywords : electric fishing * 0+ juvenile fish * point abundance sampling Subject RIV: EH - Ecology, Behaviour Impact factor: 1.031, year: 2005

  19. Thermal acclimation and thyroxine treatment modify the electric organ discharge frequency in an electric fish, Apteronotus leptorhynchus.

    Science.gov (United States)

    Dunlap, K D; Ragazzi, M A

    2015-11-01

    In ectotherms, the rate of many neural processes is determined externally, by the influence of the thermal environment on body temperature, and internally, by hormones secreted from the thyroid gland. Through thermal acclimation, animals can buffer the influence of the thermal environment by adjusting their physiology to stabilize certain processes in the face of environmental temperature change. The electric organ discharge (EOD) used by weak electric fish for electrocommunication and electrolocation is highly temperature sensitive. In some temperate species that naturally experience large seasonal fluctuations in environmental temperature, the thermal sensitivity (Q10) of the EOD shifts after long-term temperature change. We examined thermal acclimation of EOD frequency in a tropical electric fish, Apteronotus leptorhynchus that naturally experiences much less temperature change. We transferred fish between thermal environments (25.3 and 27.8 °C) and measured EOD frequency and its thermal sensitivity (Q10) over 11 d. After 6d, fish exhibited thermal acclimation to both warming and cooling, adjusting the thermal dependence of EOD frequency to partially compensate for the small change (2.5 °C) in water temperature. In addition, we evaluated the thyroid influence on EOD frequency by treating fish with thyroxine or the anti-thyroid compound propylthiouricil (PTU) to stimulate or inhibit thyroid activity, respectively. Thyroxine treatment significantly increased EOD frequency, but PTU had no effect. Neither thyroxine nor PTU treatment influenced the thermal sensitivity (Q10) of EOD frequency during acute temperature change. Thus, the EOD of Apteronotus shows significant thermal acclimation and responds to elevated thyroxine. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Precision measurement of electric organ discharge timing from freely moving weakly electric fish.

    Science.gov (United States)

    Jun, James J; Longtin, André; Maler, Leonard

    2012-04-01

    Physiological measurements from an unrestrained, untethered, and freely moving animal permit analyses of neural states correlated to naturalistic behaviors of interest. Precise and reliable remote measurements remain technically challenging due to animal movement, which perturbs the relative geometries between the animal and sensors. Pulse-type electric fish generate a train of discrete and stereotyped electric organ discharges (EOD) to sense their surroundings actively, and rapid modulation of the discharge rate occurs while free swimming in Gymnotus sp. The modulation of EOD rates is a useful indicator of the fish's central state such as resting, alertness, and learning associated with exploration. However, the EOD pulse waveforms remotely observed at a pair of dipole electrodes continuously vary as the fish swims relative to the electrodes, which biases the judgment of the actual pulse timing. To measure the EOD pulse timing more accurately, reliably, and noninvasively from a free-swimming fish, we propose a novel method based on the principles of waveform reshaping and spatial averaging. Our method is implemented using envelope extraction and multichannel summation, which is more precise and reliable compared with other widely used threshold- or peak-based methods according to the tests performed under various source-detector geometries. Using the same method, we constructed a real-time electronic pulse detector performing an additional online pulse discrimination routine to enhance further the detection reliability. Our stand-alone pulse detector performed with high temporal precision (<10 μs) and reliability (error <1 per 10(6) pulses) and permits longer recording duration by storing only event time stamps (4 bytes/pulse).

  1. The energetics of electric organ discharge generation in gymnotiform weakly electric fish.

    Science.gov (United States)

    Salazar, Vielka L; Krahe, Rüdiger; Lewis, John E

    2013-07-01

    Gymnotiform weakly electric fish produce an electric signal to sense their environment and communicate with conspecifics. Although the generation of such relatively large electric signals over an entire lifetime is expected to be energetically costly, supporting evidence to date is equivocal. In this article, we first provide a theoretical analysis of the energy budget underlying signal production. Our analysis suggests that wave-type and pulse-type species invest a similar fraction of metabolic resources into electric signal generation, supporting previous evidence of a trade-off between signal amplitude and frequency. We then consider a comparative and evolutionary framework in which to interpret and guide future studies. We suggest that species differences in signal generation and plasticity, when considered in an energetics context, will not only help to evaluate the role of energetic constraints in the evolution of signal diversity but also lead to important general insights into the energetics of bioelectric signal generation.

  2. Electric organ discharge diversification in mormyrid weakly electric fish is associated with differential expression of voltage-gated ion channel genes.

    Science.gov (United States)

    Nagel, Rebecca; Kirschbaum, Frank; Tiedemann, Ralph

    2017-03-01

    In mormyrid weakly electric fish, the electric organ discharge (EOD) is used for species recognition, orientation and prey localization. Produced in the muscle-derived adult electric organ, the EOD exhibits a wide diversity across species in both waveform and duration. While certain defining EOD characteristics can be linked to anatomical features of the electric organ, many factors underlying EOD differentiation are yet unknown. Here, we report the differential expression of 13 Kv1 voltage-gated potassium channel genes, two inwardly rectifying potassium channel genes, two previously studied sodium channel genes and an ATPase pump in two sympatric species of the genus Campylomormyrus in both the adult electric organ and skeletal muscle. Campylomormyrus compressirostris displays a basal EOD, largely unchanged during development, while C. tshokwe has an elongated, putatively derived discharge. We report an upregulation in all Kv1 genes in the electric organ of Campylomormyrus tshokwe when compared to both skeletal muscle and C. compressirostris electric organ. This pattern of upregulation in a species with a derived EOD form suggests that voltage-gated potassium channels are potentially involved in the diversification of the EOD signal among mormyrid weakly electric fish.

  3. Active sensing associated with spatial learning reveals memory-based attention in an electric fish.

    Science.gov (United States)

    Jun, James J; Longtin, André; Maler, Leonard

    2016-05-01

    Active sensing behaviors reveal what an animal is attending to and how it changes with learning. Gymnotus sp, a gymnotiform weakly electric fish, generates an electric organ discharge (EOD) as discrete pulses to actively sense its surroundings. We monitored freely behaving gymnotid fish in a large dark "maze" and extracted their trajectories and EOD pulse pattern and rate while they learned to find food with electrically detectable landmarks as cues. After training, they more rapidly found food using shorter, more stereotyped trajectories and spent more time near the food location. We observed three forms of active sensing: sustained high EOD rates per unit distance (sampling density), transient large increases in EOD rate (E-scans) and stereotyped scanning movements (B-scans) were initially strong at landmarks and food, but, after learning, intensified only at the food location. During probe (no food) trials, after learning, the fish's search area and intense active sampling was still centered on the missing food location, but now also increased near landmarks. We hypothesize that active sensing is a behavioral manifestation of attention and essential for spatial learning; the fish use spatial memory of landmarks and path integration to reach the expected food location and confine their attention to this region. Copyright © 2016 the American Physiological Society.

  4. Conflicts between sensory performance and locomotion in weakly electric fish

    Science.gov (United States)

    Maciver, Malcolm; Shirgaonkar, Anup; Patankar, Neelesh

    2008-11-01

    The knifefish Apteronotus albifrons hunts for small water insects at night using a self-generated electric field to perceive its world. Using this unique sensory adaptation, the fish senses prey that are near its body with a detection volume that approximates a cylinder that has a length ten times its radius, similar to the fish's elongated body plan. If the fish swims straight, then the back portion of the actively generated detection volume is scanning fluid already scanned by the front portion, but the energy expended to overcome drag is minimized. If it swims with the body pitched, then the rate of volume scanned for prey is increased, but the energy needed to overcome body drag is also increased. In this work we examine the compromise the fish makes between minimizing energy in overcoming drag and maximizing scan rate. We use computational fluid dynamics simulations to assess the impact of changes in body pitch angle on drag, and computational neuroscience simulations to assess the shape and size of the prey detection volume and how body angle changes the scan volume rate.

  5. Sensory flow shaped by active sensing: sensorimotor strategies in electric fish.

    Science.gov (United States)

    Hofmann, Volker; Sanguinetti-Scheck, Juan I; Künzel, Silke; Geurten, Bart; Gómez-Sena, Leonel; Engelmann, Jacob

    2013-07-01

    Goal-directed behavior in most cases is composed of a sequential order of elementary motor patterns shaped by sensorimotor contingencies. The sensory information acquired thus is structured in both space and time. Here we review the role of motion during the generation of sensory flow focusing on how animals actively shape information by behavioral strategies. We use the well-studied examples of vision in insects and echolocation in bats to describe commonalities of sensory-related behavioral strategies across sensory systems, and evaluate what is currently known about comparable active sensing strategies in electroreception of electric fish. In this sensory system the sensors are dispersed across the animal's body and the carrier source emitting energy used for sensing, the electric organ, is moved while the animal moves. Thus ego-motions strongly influence sensory dynamics. We present, for the first time, data of electric flow during natural probing behavior in Gnathonemus petersii (Mormyridae), which provide evidence for this influence. These data reveal a complex interdependency between the physical input to the receptors and the animal's movements, posture and objects in its environment. Although research on spatiotemporal dynamics in electrolocation is still in its infancy, the emerging field of dynamical sensory systems analysis in electric fish is a promising approach to the study of the link between movement and acquisition of sensory information.

  6. Electric organ discharge patterns during group hunting by a mormyrid fish.

    Science.gov (United States)

    Arnegard, Matthew E; Carlson, Bruce A

    2005-07-07

    Weakly electric fish emit and receive low-voltage electric organ discharges (EODs) for electrolocation and communication. Since the discovery of the electric sense, their behaviours in the wild have remained elusive owing to their nocturnal habits and the inaccessible environments in which they live. The transparency of Lake Malawi provided the first opportunity to simultaneously observe freely behaving mormyrid fish and record their EODs. We observed a piscivorous mormyrid, Mormyrops anguilloides, hunting in small groups in Lake Malawi while feeding on rock-frequenting cichlids of the largest known vertebrate species flock. Video recordings yielded the novel and unexpected finding that these groups resembled hunting packs by being largely composed of the same individuals across days. We show that EOD accelerations accompany prey probing and size estimation by M. anguilloides. In addition, group members occasionally synchronize bursts of EODs with an extraordinary degree of precision afforded by the mormyrid echo response. The characteristics and context of burst synchronization suggest that it may function as a pack cohesion signal. Our observations highlight the potential richness of social behaviours in a basal vertebrate lineage, and provide a framework for future investigations of the neural mechanisms, behavioural rules and ecological significance of social predation in M. anguilloides.

  7. Comparable ages for the independent origins of electrogenesis in African and South American weakly electric fishes.

    Directory of Open Access Journals (Sweden)

    Sébastien Lavoué

    Full Text Available One of the most remarkable examples of convergent evolution among vertebrates is illustrated by the independent origins of an active electric sense in South American and African weakly electric fishes, the Gymnotiformes and Mormyroidea, respectively. These groups independently evolved similar complex systems for object localization and communication via the generation and reception of weak electric fields. While good estimates of divergence times are critical to understanding the temporal context for the evolution and diversification of these two groups, their respective ages have been difficult to estimate due to the absence of an informative fossil record, use of strict molecular clock models in previous studies, and/or incomplete taxonomic sampling. Here, we examine the timing of the origins of the Gymnotiformes and the Mormyroidea using complete mitogenome sequences and a parametric bayesian method for divergence time reconstruction. Under two different fossil-based calibration methods, we estimated similar ages for the independent origins of the Mormyroidea and Gymnotiformes. Our absolute estimates for the origins of these groups either slightly postdate, or just predate, the final separation of Africa and South America by continental drift. The most recent common ancestor of the Mormyroidea and Gymnotiformes was found to be a non-electrogenic basal teleost living more than 85 millions years earlier. For both electric fish lineages, we also estimated similar intervals (16-19 or 22-26 million years, depending on calibration method between the appearance of electroreception and the origin of myogenic electric organs, providing rough upper estimates for the time periods during which these complex electric organs evolved de novo from skeletal muscle precursors. The fact that the Gymnotiformes and Mormyroidea are of similar age enhances the comparative value of the weakly electric fish system for investigating pathways to evolutionary novelty

  8. Immobilization thresholds of electrofishing relative to fish size

    Science.gov (United States)

    Dolan, C.R.; Miranda, L.E.

    2003-01-01

    Fish size and electrical waveforms have frequently been associated with variation in electrofishing effectiveness. Under controlled laboratory conditions, we measured the electrical power required by five electrical waveforms to immobilize eight fish species of diverse sizes and shapes. Fish size was indexed by total body length, surface area, volume, and weight; shape was indexed by the ratio of body length to body depth. Our objectives were to identify immobilization thresholds, elucidate the descriptors of fish size that were best associated with those immobilization thresholds, and determine whether the vulnerability of a species relative to other species remained constant across electrical treatments. The results confirmed that fish size is a key variable controlling the immobilization threshold and further suggested that the size descriptor best related to immobilization is fish volume. The peak power needed to immobilize fish decreased rapidly with increasing fish volume in small fish but decreased slowly for fish larger than 75-100 cm 3. Furthermore, when we controlled for size and shape, different waveforms did not favor particular species, possibly because of the overwhelming effect of body size. Many of the immobilization inconsistencies previously attributed to species might simply represent the effect of disparities in body size.

  9. Electric organ discharges and electric images during electrolocation

    Science.gov (United States)

    Assad, C.; Rasnow, B.; Stoddard, P. K.

    1999-01-01

    Weakly electric fish use active electrolocation - the generation and detection of electric currents - to explore their surroundings. Although electrosensory systems include some of the most extensively understood circuits in the vertebrate central nervous system, relatively little is known quantitatively about how fish electrolocate objects. We believe a prerequisite to understanding electrolocation and its underlying neural substrates is to quantify and visualize the peripheral electrosensory information measured by the electroreceptors. We have therefore focused on reconstructing both the electric organ discharges (EODs) and the electric images resulting from nearby objects and the fish's exploratory behaviors. Here, we review results from a combination of techniques, including field measurements, numerical and semi-analytical simulations, and video imaging of behaviors. EOD maps are presented and interpreted for six gymnotiform species. They reveal diverse electric field patterns that have significant implications for both the electrosensory and electromotor systems. Our simulations generated predictions of the electric images from nearby objects as well as sequences of electric images during exploratory behaviors. These methods are leading to the identification of image features and computational algorithms that could reliably encode electrosensory information and may help guide electrophysiological experiments exploring the neural basis of electrolocation.

  10. Energetic cost of communication.

    Science.gov (United States)

    Stoddard, Philip K; Salazar, Vielka L

    2011-01-15

    Communication signals may be energetically expensive or inexpensive to produce, depending on the function of the signal and the competitive nature of the communication system. Males of sexually selected species may produce high-energy advertisement signals, both to enhance detectability and to signal their size and body condition. Accordingly, the proportion of the energy budget allocated to signal production ranges from almost nothing for many signals to somewhere in excess of 50% for acoustic signals in short-lived sexually selected species. Recent data from gymnotiform electric fish reveal mechanisms that regulate energy allocated to sexual advertisement signals through dynamical remodeling of the excitable membranes in the electric organ. Further, males of the short-lived sexually selected species, Brachyhypopomus gauderio, trade off among different metabolic compartments, allocating energy to signal production while reducing energy used in other metabolic functions. Female B. gauderio, by contrast, do not trade off energy between signaling and other functions. To fuel energetically expensive signal production, we expect a continuum of strategies to be adopted by animals of different life history strategies. Future studies should explore the relation between life history and energy allocation trade-offs.

  11. The role of The Gentleman's Magazine in the dissemination of knowledge about electric fish in the eighteenth century.

    Science.gov (United States)

    Finger, Stanley; Ferguson, Ian

    2009-10-01

    Although torpedoes and Malopterurus, a Nile catfish, had been described and even used medically in antiquity, their discharges were poorly understood before the second half of the eighteenth century. It was then that their actions, along with those of certain South American "eels," became firmly associated with electricity. The realization that an animal could produce electricity marked a turning point in the history of neurophysiology, which had long described nerve actions with recourse to animal spirits. By examining The Gentleman's Magazine during the period when electric fish were becoming electrical, one can begin to appreciate how new discoveries about these unusual creatures captured the imagination of scientists and were filtered down to the literate public.

  12. Dynamic Neuron-Glia Interactions in an Oscillatory Network Controlling Behavioral Plasticity in the Weakly Electric Fish, Apteronotus leptorhynchus.

    Science.gov (United States)

    Zupanc, Günther K H

    2017-01-01

    The involvement of glial cells in the regulation of physiological functions is being increasingly recognized, yet their role in plasticity of neural oscillators has remained largely elusive. An excellent model system to address the latter function is the pacemaker nucleus of the weakly electric fish, Apteronotus leptorhynchus . This brainstem oscillator drives the fish's electric organ discharge in a one-to-one fashion, with median frequencies of 880 Hz in males and 740 Hz in females. Morphometric analysis of the pacemaker nucleus has shown that astrocytes outnumber mature neurons seven-fold, and oscillator neurons even 200-fold. A similar dominance of astrocytes occurs among the adult-born cells that differentiate into glia and neurons. The astrocytes form a dense meshwork of cells interconnected by gap junctions. The degree of association of astrocytic fibers with the neural oscillator cells, and the gap-junction coupling between individual astrocytes, exhibit a sexual dimorphism, which parallels the sexual dimorphisms in the output frequency of the pacemaker nucleus, and ultimately in the electric organ discharge of the fish. It is hypothesized that the dynamics in astroglial structure mediate differences in the capacity to buffer potassium, which increases during the generation of action potentials. These differences, in turn, affect the excitability of the neural oscillator cells, and thus the output frequency of the pacemaker nucleus. Comparison of the pacemaker nucleus with other brain oscillators suggests that modulation of the output activity is one of the chief functions of the interaction of glia with the neural oscillator cells.

  13. Status-Dependent Vasotocin Modulation of Dominance and Subordination in the Weakly Electric Fish Gymnotus omarorum

    Directory of Open Access Journals (Sweden)

    Rossana Perrone

    2018-01-01

    Full Text Available Dominant-subordinate status emerges from agonistic encounters. The weakly electric fish, Gymnotus omarorum, displays a clear-cut example of non-breeding territorial aggression. The asymmetry in the behavior of dominants and subordinates is outstanding. Dominants are highly aggressive and subordinates signal submission in a precise sequence of locomotor and electric traits: retreating, decreasing their electric organ discharge rate, and emitting transient electric signals. The hypothalamic neuropeptide arginine-vasotocin (AVT and its mammalian homolog arginine-vasopressin, are key modulators of social behavior, known to adapt their actions to different contexts. By analyzing the effects of pharmacological manipulations of the AVT system in both dominants and subordinates, we show evidence of distinct status-dependent actions of AVT. We demonstrate an endogenous effect of AVT on dominants' aggression levels: blocking the V1a AVT receptor induced a significant decrease in dominants' attack rate. AVT administered to subordinates enhanced the expression of the electric signals of submission, without affecting subordinates' locomotor displays. This study contributes a clear example of status-dependent AVT modulation of agonistic behavior in teleosts, and reveals distinctive activation patterns of the AVT system between dominants and subordinates.

  14. Status-Dependent Vasotocin Modulation of Dominance and Subordination in the Weakly Electric Fish Gymnotus omarorum.

    Science.gov (United States)

    Perrone, Rossana; Silva, Ana C

    2018-01-01

    Dominant-subordinate status emerges from agonistic encounters. The weakly electric fish, Gymnotus omarorum , displays a clear-cut example of non-breeding territorial aggression. The asymmetry in the behavior of dominants and subordinates is outstanding. Dominants are highly aggressive and subordinates signal submission in a precise sequence of locomotor and electric traits: retreating, decreasing their electric organ discharge rate, and emitting transient electric signals. The hypothalamic neuropeptide arginine-vasotocin (AVT) and its mammalian homolog arginine-vasopressin, are key modulators of social behavior, known to adapt their actions to different contexts. By analyzing the effects of pharmacological manipulations of the AVT system in both dominants and subordinates, we show evidence of distinct status-dependent actions of AVT. We demonstrate an endogenous effect of AVT on dominants' aggression levels: blocking the V1a AVT receptor induced a significant decrease in dominants' attack rate. AVT administered to subordinates enhanced the expression of the electric signals of submission, without affecting subordinates' locomotor displays. This study contributes a clear example of status-dependent AVT modulation of agonistic behavior in teleosts, and reveals distinctive activation patterns of the AVT system between dominants and subordinates.

  15. Electric Organ Discharges of Mormyrid Fish as a Possible Cue for Predatory Catfish

    Science.gov (United States)

    Hanika, S.; Kramer, B.

    During reproductive migration the electroreceptive African sharptooth catfish, Clarias gariepinus (Siluriformes), preys mainly on a weakly electric fish, the bulldog Marcusenius macrolepidotus (Mormyridae; Merron 1993). This is puzzling because the electric organ discharges of known Marcusenius species are pulses of a duration (system (optimum sensitivity, 10-30Hz Peters and Bretschneider 1981). On the recent discovery that M. macrolepidotus males emit discharges lasting approximately ten times longer than those of females (Kramer 1997a) we determined behavioral thresholds for discharges of both sexes, using synthetic playbacks of field-recorded discharges. C. gariepinus detected M. macrolepidotus male discharges down to a field gradient of 103μVpeak-peak/cm and up to a distance of 1.5m at natural field conditions. In contrast, thresholds for female discharges were not reached with our setup, and we presume the bulldogs eaten by catfish are predominantly male.

  16. Testing resonating vector strength: Auditory system, electric fish, and noise

    Science.gov (United States)

    Leo van Hemmen, J.; Longtin, André; Vollmayr, Andreas N.

    2011-12-01

    Quite often a response to some input with a specific frequency ν○ can be described through a sequence of discrete events. Here, we study the synchrony vector, whose length stands for the vector strength, and in doing so focus on neuronal response in terms of spike times. The latter are supposed to be given by experiment. Instead of singling out the stimulus frequency ν○ we study the synchrony vector as a function of the real frequency variable ν. Its length turns out to be a resonating vector strength in that it shows clear maxima in the neighborhood of ν○ and multiples thereof, hence, allowing an easy way of determining response frequencies. We study this "resonating" vector strength for two concrete but rather different cases, viz., a specific midbrain neuron in the auditory system of cat and a primary detector neuron belonging to the electric sense of the wave-type electric fish Apteronotus leptorhynchus. We show that the resonating vector strength always performs a clear resonance correlated with the phase locking that it quantifies. We analyze the influence of noise and demonstrate how well the resonance associated with maximal vector strength indicates the dominant stimulus frequency. Furthermore, we exhibit how one can obtain a specific phase associated with, for instance, a delay in auditory analysis.

  17. Electrical impedance spectroscopy for quality assessment of meat and fish: A review on basic principles, measurement methods, and recent advances

    Science.gov (United States)

    Electrical impedance spectroscopy (EIS), as an effective analytical technique for electrochemical system, has shown a wide application for food quality and safety assessment recently. Individual differences of livestock cause high variation in quality of raw meat and fish and their commercialized pr...

  18. Intragenus (Campylomormyrus) and intergenus hybrids in mormyrid fish: Physiological and histological investigations of the electric organ ontogeny.

    Science.gov (United States)

    Kirschbaum, Frank; Nguyen, Linh; Baumgartner, Stephanie; Chi, Hiu Wan Linda; Wolfart, Rene; Elarbani, Khouloud; Eppenstein, Hari; Korniienko, Yevheniia; Guido-Böhm, Lilian; Mamonekene, Victor; Vater, Marianne; Tiedemann, Ralph

    2016-10-01

    African weakly electric mormyrid fish show a high diversity of their electric organ discharge (EOD) both across and within genera. Thanks to a recently developed technique of artificial reproduction in mormyrid fish, we were able to perform hybridizations between different genera and within one genus (Campylomormyrus). The hybrids of intergenus hybridizations exhibited different degrees of reduced survival related to the phylogenetic distance of the parent species: hybrids of the crosses between C. rhynchophorus and its sister genus Gnathonemus survived and developed normally. Hybrids between C. rhynchophorus and a Mormyrus species (a more basal clade compared to Campylomormyrus s) survived up to 42days and developed many malformations, e.g., at the level of the unpaired fins. Hybrids between C. numenius and Hippopotamyrus pictus (a derived clade, only distantly related to Campylomormyrus) only survived for two days during embryological development. Eight different hybrid combinations among five Campylomormyrus species (C. tamandua, C. compressirostris, C. tshokwe, C. rhynchophorus, C. numenius) were performed. The aim of the hybridizations was to combine species with (1) either caudal or rostral position of the main stalk innervating the electrocytes in the electric organ and (2) short, median or long duration of their EOD. The hybrids, though they are still juveniles, show very interesting features concerning electrocyte geometry as well as EOD form and duration: the caudal position of the stalk is prevailing over the rostral position, and the penetration of the stalk is dominant over the non-penetrating feature (in the Campylomormyrus hybrids); in the hybrid between C. rhynchophorus and Gnathonemus petersii it is the opposite. When crossing species with long and short EODs, it is always the long duration EOD that is expressed in the hybrids. The F1-Hybrids of the cross C. tamandua×C. compressirostris are fertile: viable F2-fish could be obtained with artificial

  19. Subsecond Sensory Modulation of Serotonin Levels in a Primary Sensory Area and Its Relation to Ongoing Communication Behavior in a Weakly Electric Fish.

    Science.gov (United States)

    Fotowat, Haleh; Harvey-Girard, Erik; Cheer, Joseph F; Krahe, Rüdiger; Maler, Leonard

    2016-01-01

    Serotonergic neurons of the raphe nuclei of vertebrates project to most regions of the brain and are known to significantly affect sensory processing. The subsecond dynamics of sensory modulation of serotonin levels and its relation to behavior, however, remain unknown. We used fast-scan cyclic voltammetry to measure serotonin release in the electrosensory system of weakly electric fish, Apteronotus leptorhynchus . These fish use an electric organ to generate a quasi-sinusoidal electric field for communicating with conspecifics. In response to conspecific signals, they frequently produce signal modulations called chirps. We measured changes in serotonin concentration in the hindbrain electrosensory lobe (ELL) with a resolution of 0.1 s concurrently with chirping behavior evoked by mimics of conspecific electric signals. We show that serotonin release can occur phase locked to stimulus onset as well as spontaneously in the ELL region responsible for processing these signals. Intense auditory stimuli, on the other hand, do not modulate serotonin levels in this region, suggesting modality specificity. We found no significant correlation between serotonin release and chirp production on a trial-by-trial basis. However, on average, in the trials where the fish chirped, there was a reduction in serotonin release in response to stimuli mimicking similar-sized same-sex conspecifics. We hypothesize that the serotonergic system is part of an intricate sensory-motor loop: serotonin release in a sensory area is triggered by sensory input, giving rise to motor output, which can in turn affect serotonin release at the timescale of the ongoing sensory experience and in a context-dependent manner.

  20. Utilization of geothermal energy for drying fish products

    International Nuclear Information System (INIS)

    Arason, S.; Arnason, H.

    1992-01-01

    This paper is about industrial uses of geothermal energy for drying of fish products. Drying is an ancient method for preservation of foods, the main purpose of which is to increase the preservation time. For drying, an external source of energy is needed to extract water. In this paper an emphasis is placed on drying fish and associated processes, and how geothermal energy can be used to substitute oil or electricity. The Icelandic Fisheries Laboratories have been experimenting with different methods of drying, and several drying stations have been designed for indoor drying of fish products. Today there are more than a dozen companies in this country which are drying fish indoors using for that purpose electricity and/or geothermal energy. Further possibilities are available when fish processing plants are located in geothermal areas

  1. Dynamics and stimulus-dependence of pacemaker control during behavioral modulations in the weakly electric fish, Apteronotus.

    Science.gov (United States)

    Dye, J

    1987-08-01

    1. Weakly electric fish generate around their bodies low-amplitude, AC electric fields which are used both for the detection of objects and intraspecific communication. The types of modulation in this signal of which the high-frequency wave-type gymnotiform, Apteronotus, is capable are relatively few and stereotyped. Chief among these is the chirp, a signal used in courtship and agonistic displays. Chirps are brief and rapid accelerations in the normally highly regular electric organ discharge (EOD) frequency. 2. Chirping can be elicited artificially in these animals by the use of a stimulus regime identical to that typically used to elicit another behavior, the jamming avoidance response (JAR). The neuronal basis for the JAR, a much slower and lesser alteration in EOD frequency, is well understood. Examination of the stimulus features which induce chirping show that, like the JAR, there is a region of frequency differences between the fish's EOD and the interfering signal that maximally elicits the response. Moreover, the response is sex-specific with regard to the sign of the frequency difference, with females chirping preferentially on the positive and most males on the negative Df. These features imply that the sensory mechanisms involved in the triggering of these communicatory behaviors are fundamentally similar to those explicated for the JAR. 3. Additionally, two other modulatory behaviors of unknown significance are described. The first is a non-selective rise in EOD frequency associated with a JAR stimulus, occurring regardless of the sign of the Df. This modulation shares many characteristics with the JAR. The second behavior, which we have termed a 'yodel', is distinct from and kinetically intermediate to chirping and the JAR. Moreover, unlike the other studied electromotor behaviors it is generally produced only after the termination of the eliciting stimulus.

  2. Electrical Impedance Spectroscopy for Quality Assessment of Meat and Fish: A Review on Basic Principles, Measurement Methods, and Recent Advances

    Directory of Open Access Journals (Sweden)

    Xin Zhao

    2017-01-01

    Full Text Available Electrical impedance spectroscopy (EIS, as an effective analytical technique for electrochemical system, has shown a wide application for food quality and safety assessment recently. Individual differences of livestock cause high variation in quality of raw meat and fish and their commercialized products. Therefore, in order to obtain the definite quality information and ensure the quality of each product, a fast and on-line detection technology is demanded to be developed to monitor product processing. EIS has advantages of being fast, nondestructive, inexpensive, and easily implemented and shows potential to develop on-line detecting instrument to replace traditional methods to realize time, cost, skilled persons saving and further quality grading. This review outlines the fundamental theories and two common measurement methods of EIS applied to biological tissue, summarizes its application specifically for quality assessment of meat and fish, and discusses challenges and future trends of EIS technology applied for meat and fish quality assessment.

  3. Multisensor for fish quality determination

    DEFF Research Database (Denmark)

    Olafsdottir, G.; Nesvadba, P.; Di Natale, C.

    2004-01-01

    The European fish industry is still reluctant to implement methods other than sensory to monitor freshness and quality of fish products, although general concensus exists about the importance of various quality attributes and the need for methods to monitor quality. The objective of the project...... FAIR CT98-4076 (MUSTEC) was to evaluate several physico-chemical techniques and to integrate their outputs into a more robust estimate of the freshness quality of fish. The techniques used for this multisensor approach were based on visible light spectroscopy, electrical properties, image analysis...... sensory score. The outcome provides a basis for the construction and industrial exploitation of multi-sensor-devices for defining the quality of fish....

  4. Temporal code-driven stimulation: definition and application to electric fish signaling

    Directory of Open Access Journals (Sweden)

    Angel Lareo

    2016-10-01

    Full Text Available Closed-loop activity-dependent stimulation is a powerful methodology to assess information processing in biological systems. In this context, the development of novel protocols, their implementation in bioinformatics toolboxes and their application to different description levels open up a wide range of possibilities in the study of biological systems. We developed a methodology for studying biological signals representing them as temporal sequences of binary events. A specific sequence of these events (code is chosen to deliver a predefined stimulation in a closed-loop manner. The response to this code-driven stimulation can be used to characterize the system. This methodology was implemented in a real time toolbox and tested in the context of electric fish signaling. We show that while there are codes that evoke a response that cannot be distinguished from a control recording without stimulation, other codes evoke a characteristic distinct response. We also compare the code-driven response to open-loop stimulation. The discussed experiments validate the proposed methodology and the software toolbox.

  5. Real-Time Localization of Moving Dipole Sources for Tracking Multiple Free-Swimming Weakly Electric Fish

    Science.gov (United States)

    Jun, James Jaeyoon; Longtin, André; Maler, Leonard

    2013-01-01

    In order to survive, animals must quickly and accurately locate prey, predators, and conspecifics using the signals they generate. The signal source location can be estimated using multiple detectors and the inverse relationship between the received signal intensity (RSI) and the distance, but difficulty of the source localization increases if there is an additional dependence on the orientation of a signal source. In such cases, the signal source could be approximated as an ideal dipole for simplification. Based on a theoretical model, the RSI can be directly predicted from a known dipole location; but estimating a dipole location from RSIs has no direct analytical solution. Here, we propose an efficient solution to the dipole localization problem by using a lookup table (LUT) to store RSIs predicted by our theoretically derived dipole model at many possible dipole positions and orientations. For a given set of RSIs measured at multiple detectors, our algorithm found a dipole location having the closest matching normalized RSIs from the LUT, and further refined the location at higher resolution. Studying the natural behavior of weakly electric fish (WEF) requires efficiently computing their location and the temporal pattern of their electric signals over extended periods. Our dipole localization method was successfully applied to track single or multiple freely swimming WEF in shallow water in real-time, as each fish could be closely approximated by an ideal current dipole in two dimensions. Our optimized search algorithm found the animal’s positions, orientations, and tail-bending angles quickly and accurately under various conditions, without the need for calibrating individual-specific parameters. Our dipole localization method is directly applicable to studying the role of active sensing during spatial navigation, or social interactions between multiple WEF. Furthermore, our method could be extended to other application areas involving dipole source

  6. Real-Time Localization of Moving Dipole Sources for Tracking Multiple Free-Swimming Weakly Electric Fish.

    Directory of Open Access Journals (Sweden)

    James Jaeyoon Jun

    Full Text Available In order to survive, animals must quickly and accurately locate prey, predators, and conspecifics using the signals they generate. The signal source location can be estimated using multiple detectors and the inverse relationship between the received signal intensity (RSI and the distance, but difficulty of the source localization increases if there is an additional dependence on the orientation of a signal source. In such cases, the signal source could be approximated as an ideal dipole for simplification. Based on a theoretical model, the RSI can be directly predicted from a known dipole location; but estimating a dipole location from RSIs has no direct analytical solution. Here, we propose an efficient solution to the dipole localization problem by using a lookup table (LUT to store RSIs predicted by our theoretically derived dipole model at many possible dipole positions and orientations. For a given set of RSIs measured at multiple detectors, our algorithm found a dipole location having the closest matching normalized RSIs from the LUT, and further refined the location at higher resolution. Studying the natural behavior of weakly electric fish (WEF requires efficiently computing their location and the temporal pattern of their electric signals over extended periods. Our dipole localization method was successfully applied to track single or multiple freely swimming WEF in shallow water in real-time, as each fish could be closely approximated by an ideal current dipole in two dimensions. Our optimized search algorithm found the animal's positions, orientations, and tail-bending angles quickly and accurately under various conditions, without the need for calibrating individual-specific parameters. Our dipole localization method is directly applicable to studying the role of active sensing during spatial navigation, or social interactions between multiple WEF. Furthermore, our method could be extended to other application areas involving dipole

  7. Design and testing of small scale fish meat bone separator useful for fish processing.

    Science.gov (United States)

    Ali Muhammed, M; Manjunatha, N; Murthy, K Venkatesh; Bhaskar, N

    2015-06-01

    The present study relates to the food processing machinery and, more specifically machine for producing boneless comminuted meat from raw fish fillet. This machine is of belt and drum type meat bone separator designed for small scale fish processing in a continuous mode. The basic principal involved in this machine is compression force. The electric geared motor consists of 1HP and the conveyor belt has a linear velocity of 19 to 22 m min(-1), which was sufficient to debone the fish effectively. During the meat bone separation trials an efficiency up to 75 % on dressed fish weight basis was observed and with a capacity to separate 70 kg h(-1) of meat from fish at the machine speed of 25 rpm. During the trials, it was demonstrated that there was no significant change in the proximate composition of comminuted fish meat when compared to unprocessed fish meat. This design has a greater emphasis on hygiene, provision for cleaning-in-place (CIP) and gives cost effective need and reliability for small scale industries to produce fish meat in turn used for their value added products.

  8. Development of Solar Drying Model for Selected Cambodian Fish Species

    Science.gov (United States)

    Hubackova, Anna; Kucerova, Iva; Chrun, Rithy; Chaloupkova, Petra; Banout, Jan

    2014-01-01

    A solar drying was investigated as one of perspective techniques for fish processing in Cambodia. The solar drying was compared to conventional drying in electric oven. Five typical Cambodian fish species were selected for this study. Mean solar drying temperature and drying air relative humidity were 55.6°C and 19.9%, respectively. The overall solar dryer efficiency was 12.37%, which is typical for natural convection solar dryers. An average evaporative capacity of solar dryer was 0.049 kg·h−1. Based on coefficient of determination (R 2), chi-square (χ 2) test, and root-mean-square error (RMSE), the most suitable models describing natural convection solar drying kinetics were Logarithmic model, Diffusion approximate model, and Two-term model for climbing perch and Nile tilapia, swamp eel and walking catfish and Channa fish, respectively. In case of electric oven drying, the Modified Page 1 model shows the best results for all investigated fish species except Channa fish where the two-term model is the best one. Sensory evaluation shows that most preferable fish is climbing perch, followed by Nile tilapia and walking catfish. This study brings new knowledge about drying kinetics of fresh water fish species in Cambodia and confirms the solar drying as acceptable technology for fish processing. PMID:25250381

  9. Signal modulation as a mechanism for handicap disposal

    Science.gov (United States)

    Gavassa, Sat; Silva, Ana C.; Gonzalez, Emmanuel; Stoddard, Philip K.

    2012-01-01

    Signal honesty may be compromised when heightened competition provides incentive for signal exaggeration. Some degree of honesty might be maintained by intrinsic handicap costs on signalling or through imposition of extrinsic costs, such as social punishment of low quality cheaters. Thus, theory predicts a delicate balance between signal enhancement and signal reliability that varies with degree of social competition, handicap cost, and social cost. We investigated whether male sexual signals of the electric fish Brachyhypopomus gauderio would become less reliable predictors of body length when competition provides incentives for males to boost electric signal amplitude. As expected, social competition under natural field conditions and in controlled lab experiments drove males to enhance their signals. However, signal enhancement improved the reliability of the information conveyed by the signal, as revealed in the tightening of the relationship between signal amplitude and body length. Signal augmentation in male B. gauderio was independent of body length, and thus appeared not to be curtailed through punishment of low quality (small) individuals. Rather, all individuals boosted their signals under high competition, but those whose signals were farthest from the predicted value under low competition boosted signal amplitude the most. By elimination, intrinsic handicap cost of signal production, rather than extrinsic social cost, appears to be the basis for the unexpected reinforcement of electric signal honesty under social competition. Signal modulation may provide its greatest advantage to the signaller as a mechanism for handicap disposal under low competition rather than as a mechanism for exaggeration of quality under high competition. PMID:22665940

  10. Cellular and circuit properties supporting different sensory coding strategies in electric fish and other systems.

    Science.gov (United States)

    Marsat, Gary; Longtin, André; Maler, Leonard

    2012-08-01

    Neural codes often seem tailored to the type of information they must carry. Here we contrast the encoding strategies for two different communication signals in electric fish and describe the underlying cellular and network properties that implement them. We compare an aggressive signal that needs to be quickly detected, to a courtship signal whose quality needs to be evaluated. The aggressive signal is encoded by synchronized bursts and a predictive feedback input is crucial in separating background noise from the communication signal. The courtship signal is accurately encoded through a heterogenous population response allowing the discrimination of signal differences. Most importantly we show that the same strategies are used in other systems arguing that they evolved similar solutions because they faced similar tasks. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Development of Solar Drying Model for Selected Cambodian Fish Species

    Directory of Open Access Journals (Sweden)

    Anna Hubackova

    2014-01-01

    Full Text Available A solar drying was investigated as one of perspective techniques for fish processing in Cambodia. The solar drying was compared to conventional drying in electric oven. Five typical Cambodian fish species were selected for this study. Mean solar drying temperature and drying air relative humidity were 55.6°C and 19.9%, respectively. The overall solar dryer efficiency was 12.37%, which is typical for natural convection solar dryers. An average evaporative capacity of solar dryer was 0.049 kg·h−1. Based on coefficient of determination (R2, chi-square (χ2 test, and root-mean-square error (RMSE, the most suitable models describing natural convection solar drying kinetics were Logarithmic model, Diffusion approximate model, and Two-term model for climbing perch and Nile tilapia, swamp eel and walking catfish and Channa fish, respectively. In case of electric oven drying, the Modified Page 1 model shows the best results for all investigated fish species except Channa fish where the two-term model is the best one. Sensory evaluation shows that most preferable fish is climbing perch, followed by Nile tilapia and walking catfish. This study brings new knowledge about drying kinetics of fresh water fish species in Cambodia and confirms the solar drying as acceptable technology for fish processing.

  12. Impingement of juvenile and adult fishes during cooling water withdrawal

    International Nuclear Information System (INIS)

    McFarlane, R.W.

    1978-01-01

    Juvenile and adult fishes are impinged upon trash removal screens as Savannah River water is withdrawn for use on the Savannah River Plant (SRP). Thirty-six species of fish, representing half of all riverine species known from the area, were impinged on the screens at three SRP pumping stations during 1977. Based on the average of 11.2 fish impinged per day, annual impingement is estimated to be 4088 fish. SRP thus ranks third lowest for impingement recently reported for 33 electric power plants

  13. Seasonal distribution and abundance of Ohio River fishes at the J.M. Stuart Electric Generating Station

    International Nuclear Information System (INIS)

    Yoder, C.O.; Gammon, J.R.

    1976-01-01

    Distributions of Ohio River fishes were studied in the vicinity of a 2400-Mw coal-fired electric generating plant. Three thermally elevated zones, two ambient river zones, and a backwater zone were sampled intensively from June 1974 through February 1975 following the completion of all four units of the power plant. Less intensive collections were made preceding and during construction from 1970 to 1973. Overall variations in water temperature in 1974 to 1975 ranged from 6 to 40 0 C in the heated zones, 4 to 30 0 C in the ambient river zones, and 5 to 27 0 C in the backwater zone. Seasonal and spatial differences in abundance, diversity, and faunal associations were largely influenced by temperature. Notable changes in species populations from 1970 to 1975 were observed which were attributed to power-plant operation. Although seasonal definitions in terms of summer, fall, and winter were generally used, they were of very limited value, as demonstrated by annual fluctuations in community parameters. Apparently near-freezing temperatures in the ambient river zones, as well as high summer temperatures in the effluent canal, limit the time fish can spend in these areas and force them to seek more hospitable temperatures. This suggests that there are critical winter as well as summer months, with spring/fall transitional periods in between in the vicinity of thermal effluents

  14. Sensory processing and corollary discharge effects in posterior caudal lobe Purkinje cells in a weakly electric mormyrid fish.

    Science.gov (United States)

    Alviña, Karina; Sawtell, Nathaniel B

    2014-07-15

    Although it has been suggested that the cerebellum functions to predict the sensory consequences of motor commands, how such predictions are implemented in cerebellar circuitry remains largely unknown. A detailed and relatively complete account of predictive mechanisms has emerged from studies of cerebellum-like sensory structures in fish, suggesting that comparisons of the cerebellum and cerebellum-like structures may be useful. Here we characterize electrophysiological response properties of Purkinje cells in a region of the cerebellum proper of weakly electric mormyrid fish, the posterior caudal lobe (LCp), which receives the same mossy fiber inputs and projects to the same target structures as the electrosensory lobe (ELL), a well-studied cerebellum-like structure. We describe patterns of simple spike and climbing fiber activation in LCp Purkinje cells in response to motor corollary discharge, electrosensory, and proprioceptive inputs and provide evidence for two functionally distinct Purkinje cell subtypes within LCp. Protocols that induce rapid associative plasticity in ELL fail to induce plasticity in LCp, suggesting differences in the adaptive functions of the two structures. Similarities and differences between LCp and ELL are discussed in light of these results. Copyright © 2014 the American Physiological Society.

  15. Electrolocation-communication discharges of the fish Gymnotus carapo L. (Gymnotidae: Gymnotiformes during behavioral sleep

    Directory of Open Access Journals (Sweden)

    Stopa R.M.

    1999-01-01

    Full Text Available Technical problems have hampered the study of sleep in teleosts. The electrical discharges of Gymnotus carapo L. (Gymnotidae: Gymnotiformes were monitored to evaluate their ease and reliability as parameters to study sleep. The discharges were detected by electrodes immersed in a glass aquarium and were recorded on a conventional polygraph. G. carapo showed conspicuous signs of behavioral sleep. During these periods, opercular beat rates were counted, electric discharges recorded, and the "sharp discharge increase" (SDI of the orienting reflex was investigated. All 20 animals monitored maintained electrical discharges during behavioral sleep. The discharge frequencies during sleep (50.3 ± 10.4 Hz were not significantly different from those observed when the fish was awake and inactive (57.2 ± 12.1 Hz (Wilcoxon matched-pairs signed-ranks test, P>0.05. However, the SDI, which was prevalent in the awake fish, was not observed during periods of behavioral sleep. Additional observations showed that the species had cannibalistic habits. When presented with electrical discharges from a conspecific, the sleeping fish showed an initial decrease or pause in discharge frequency, while the awake fish did not have this response. We conclude that the electrical discharges of G. carapo were not conspicuous indicators of behavioral sleep. Discharges may have been maintained during sleep for sensory purposes, i.e., conspecific detection and avoidance of cannibalistic attacks.

  16. Effects of electro-fishing on galvano-taxis and carcass quality characteristics in sea bass (Dicentrarchus labrax

    Directory of Open Access Journals (Sweden)

    Edo D’Agaro

    2010-01-01

    Full Text Available The aim of this study was to investigate the effects of electro-fishing in sea water. We evaluated the feasibility of an electro-fishing system using numerical simulations for laboratory tanks and the open sea and performing a laboratory experiment. A non-homogeneous bi-dimensional electric-field model for marine water and fish based on discrete formulation of electro-magnetic field equations was developed using GAME (geometric approach for Maxwell equations software. Voltage gradients inside the fish and close to the body were determined. Re- sults showed that fish in the open sea and in groups had greater internal voltage differences than did fish in tanks and single fish. Sea bass (length:10 and 30 cm were exposed in laboratory tanks to pulsed direct current (PDC, 25-125 Hz and duty cycle (5-40%. We measured the electro-taxis and tetanus thresholds after electrical exposure. It is significant that these values decreased with increasing the size of fish. No differences were found after electro-fishing on overall appearance, internal and external haemorrhage, standard freshness scoring techniques and carcass quality characteristics

  17. Strontium-90 and cesium-137 in freshwater fish

    International Nuclear Information System (INIS)

    1983-01-01

    Sr-90 and Cs-137 in freshwater fish were determined using radiochemical analysis. Three species of fish (Carassius auratus, Cyprinus carpio, and Hypomesus transpacificus nipponensis) were collected during the fishing season from seven sampling locations. Only edible part was used in case of larger sized fish, and the whole part was used in case of smaller ones. Each sample was weighed and placed in a stainless steel pan or a porcelain dish. After carbonized, the sample was ashed in an electric muffle furnace. The maximum values of Sr-90 and Cs-137 were 49.0 +- 1.30 pCi/kg and 8.5 +- 0.64 pCi/kg in Carassius auratus collected from Kyoto and Fukui, respectively, in December 1983. (Namekawa, K.)

  18. Long-term recognition memory of individual conspecifics is associated with telencephalic expression of Egr-1 in the electric fish Apteronotus leptorhynchus.

    Science.gov (United States)

    Harvey-Girard, Erik; Tweedle, Jessica; Ironstone, Joel; Cuddy, Martin; Ellis, William; Maler, Leonard

    2010-07-15

    Primates and songbirds can learn to recognize individual conspecifics based on complex sensory cues; this requires a large, highly differentiated dorsal telencephalon. Here we show that the electric fish Apteronotus leptorhynchus can learn to recognize individual conspecifics based on a simple cue, the beat frequency of their summed sinusoidal electric organ discharges (EOD). Male fish produce transient communication signals (chirps) in response to mimic EODs. The chirp response habituates over repeated stimulus presentations within one experimental session, continues to habituate over successive daily sessions and is nearly extinguished after 5-7 days. Habituation of the chirp response was specific to the presented beat frequency. The conversion of short- to long-term habituation could be disrupted by cooling the head 30 minutes after the daily habituation trials. Consolidation of long-term memory in mammals is thought to involve induced expression of an immediate early gene, Egr-1. We cloned the Apteronotid homolog of the Egr-1 gene and found that chirp-evoking stimuli induced strong expression of its mRNA within the dorsal (Dd), central (DC), and lateral (DL) subdivisions of the dorsal telencephalon. Interestingly, the dorsolateral region is hypothesized to be homologous to the amniote hippocampal formation. We conclude that A. leptorhynchus can learn to identify individual conspecifics based on their EOD frequency and can remember these frequencies for several days. We hypothesize that this form of learning, as in primates and songbirds, requires a subset of dorsal telencephalic areas and involves a consolidation-like process that includes the expression of the transcription factor AptEgr-1.

  19. Design of multisegmented freeform lens for LED fishing/working lamp with high efficiency.

    Science.gov (United States)

    Lai, Min-Feng; Anh, Nguyen Doan Quoc; Gao, Jia-Zhi; Ma, Hsin-Yi; Lee, Hsiao-Yi

    2015-10-01

    A novel LED fishing/working light is proposed to enhance the lighting efficiency of a fishing boat. The study is focused on the freeform secondary lens design so as to create a lamp that attracts fish and sheds light on the deck for the crew's work. The experimental results show that the proposed multisegmented freeform lens can deliver the proposed aim, giving 3 times as much illuminating power as the traditional high-intensity discharge fishing lamp does with the same input of electrical power.

  20. Diversity of neotropical electric fish Microsternarchus (Teleostei: Gymnotiformes: Hypopomidae: an electrophysiological and geometric morphometric approach

    Directory of Open Access Journals (Sweden)

    Adília Nogueira

    2015-11-01

    Full Text Available The South American hypopomid electric fish tribe Microsternarchini includes three small species from the Upper Orinoco and Negro rivers. These are placed in monotypic genera: Microsternarchus, Racenisia and Procerusternarchus. Recent collections from tributaries in Negro, Solimões and Amazonas Basins have revealed new specimens of Microsternarchus with significant variations in external morphology and in Electric Organ Discharge parameters (EOD. In order to estimate the diversity within the genus a previous molecular study was done using DNA barcoding, that suggested the presence of multiple Microsternarchus's lineages with high levels of genetic divergence between them. Here we try to determine if the variation in morphology and EOD parameters in the new specimens meet the genetic divergence found. To test the presence of differences in shape among the different lineages we performed a geometric morphometric analysis, which included a relative warp and multivariate analysis on distances between 14 anatomical landmarks defined on the basis of external morphology and homologous among the lineages. The EOD variations were also explored using multivariate analyses of 20 electrophysiological parameters calculated through an algorithm developed in Matlab. The results show that there are significant differences in body shape and EOD in three lineages of Microsternarchus, and the features that contributed most were related to the shape of the head, the coefficient of variation of the signal and the duration and area of the different phases of the pulse. The discrimination of the three lineages confirms the occurrence of new species in the group that are currently being described.

  1. Impact of habitat diversity on the sampling effort required for the assessment of river fish communities and IBI

    NARCIS (Netherlands)

    Van Liefferinge, C.; Simoens, I.; Vogt, C.; Cox, T.J.S.; Breine, J.; Ercken, D.; Goethals, P.; Belpaire, C.; Meire, P.

    2010-01-01

    The spatial variation in the fish communities of four small Belgian rivers with variable habitat diversity was investigated by electric fishing to define the minimum sampling distance required for optimal fish stock assessment and determination of the Index of Biotic Integrity. This study shows that

  2. Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington

    International Nuclear Information System (INIS)

    1996-12-01

    The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included

  3. Environmental assessment, K Pool fish rearing, Hanford Site, Richland, Washington

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The US Department of Energy (DOE) has a need to respond to a request to lease facilities at the Hanford Site 100-KE and 100-KW filter plant pools (K Pools) for fish rearing activities. These fish rearing activities would be: (1) business ventures with public and private funds and (2) long-term enhancement and supplementation programs for game fish populations in the Columbia River Basin. The proposed action is to enter into a use permit or lease agreement with the YIN or other parties who would rear fish in the 100-K Area Pools. The proposed action would include necessary piping, pump, and electrical upgrades of the facility; cleaning and preparation of the pools; water withdrawal from the Columbia River, and any necessary water or wastewater treatment; and introduction, rearing and release of fish. Future commercial operations may be included.

  4. Evaluation of an eicher fish diversion screen at Elwha Dam

    International Nuclear Information System (INIS)

    Winchell, F.C.; Sullivan, C.W.

    1991-01-01

    This paper reports that in the spring of 1990, the Electric Power Research Institute (EPRI) initiated testing of an inclined fish screen installed in a 9-foot diameter penstock at the Elwhat Hydroelectric Project in Washington State. In tests performed with coho salmon smolts, over 99 percent of the fish were diverted without mortality. At penstock velocities from 4 to 6 fps, less than 0.1 percent of the fish had scale loss exceeding 16 percent on either side (considered descaled in criteria used on the Columbia River), and less than 5 percent showed any type of injury. Slightly more descaling was observed at higher penstock velocities. At the maximum velocity tested (7.8 fps), 3.6 percent of the fish had scale loss of over 16 percent, and 18.1 percent of the fish had scale loss between 3 percent and 16 percent. Mortality after a 3 to 10-day holding period averaged 0.21 percent for test fish and 0.14 percent for controls

  5. Concurrent assessment of fish and habitat in warmwater streams in Wyoming

    Science.gov (United States)

    Quist, M.C.; Hubert, W.A.; Rahel, F.J.

    2006-01-01

    Fisheries research and management in North America have focused largely on sport fishes, but native non-game fishes have attracted increased attention due to their declines. The Warmwater Stream Assessment (WSA) was developed to evaluate simultaneously both fish and habitat in Wyoming streams by a process that includes three major components: (1) stream-reach selection and accumulation of existing information, (2) fish and habitat sampling and (3) summarisation and evaluation of fish and habitat information. Fish are sampled by electric fishing or seining and habitat is measured at reach and channel-unit (i.e. pool, run, riffle, side channel, or backwater) scales. Fish and habitat data are subsequently summarised using a data-matrix approach. Hierarchical decision trees are used to assess critical habitat requirements for each fish species expected or found in the reach. Combined measurements of available habitat and the ecology of individual species contribute to the evaluation of the observed fish assemblage. The WSA incorporates knowledge of the fish assemblage and habitat features to enable inferences of factors likely influencing both the fish assemblage and their habitat. The WSA was developed for warmwater streams in Wyoming, but its philosophy, process and conceptual basis may be applied to environmental assessments in other geographical areas. ?? 2006 Blackwell Publishing Ltd.

  6. Fish habitat considerations associated with hydro-electric developments in Quebec region

    International Nuclear Information System (INIS)

    Bain, H.; Stoneman, M.

    2005-01-01

    Alternative approaches for evaluating the effects of 2 large Hydro Quebec proposed facilities on fish habitats were presented. The proposed projects will convert long stretches of river into water reservoirs and reduce the flow in the rivers below the impoundments for parts of the year. Rivers will be transformed into water reservoirs upstream by the dams, and a moderately large river will be transformed downstream into a much smaller river with a regulated flow. Productive capacity of fish populations is difficult to measure in large water bodies, and complications in the evaluation process have posed problems in the application of a traditional no-net-loss policy. It was suggested that estimates of biomass and productivity should be obtained from established methods of electrofishing combined with maps of the river and stream characteristics. For lakes and reservoirs, biomass and production will be estimated from models using a morphoedaphic index and measures of lake reservoir areas. Productivity will be partitioned among species according to surveys of existing lakes and reservoirs. It was also proposed that mitigation and compensation should be considered on a case-by-case basis related to importance of impact on fish production; geographic range of the impacts; regional fisheries management objectives for commercial, recreational, and subsistence fisheries and biodiversity conservation. Special attention will be given to listed species such as Atlantic salmon and lake sturgeon. Additional field sampling was recommended in areas impacted by the developments. Concerns about the technical methods used in sampling and monitoring data were reviewed, as well as issues concerning protected and unprotected species. It was suggested that predictive models of fish population characteristics will need to be parameterized for temperature ranges associated with the projects. It was noted that habitat suitability index methods do not consider the ecological flexibility

  7. Fish allergy and fish allergens

    DEFF Research Database (Denmark)

    Kuehn, A; Hilger, Christiane; Ollert, Markus

    2016-01-01

    Fish is one of the main elicitors for food allergies. For a long time, the clinical picture of fish allergy was reduced to the following features. First, fish-allergic patients suffer from a high IgE cross-reactivity among fishes so that they have to avoid all species. Second, clinically relevant...... symptoms are linked to the presence of IgE-antibodies recognizing parvalbumin, the fish panallergen. This view was challenged by results from recent studies as follows. 1. Allergic reactions which are limited to single or several fish species (mono-or oligosensitisations) apply not only to single cases...... but patients with this phenotype constitute an important sub-group among fish-allergic individuals. 2. Newly identified fish allergens, enolases, aldolases, and fish gelatin, are of high relevance as the majority of the fish-allergic individuals seem to develop specific IgE against these proteins. The present...

  8. Potential for electropositive metal to reduce the interactions of Atlantic sturgeon with fishing gear.

    Science.gov (United States)

    Bouyoucos, Ian; Bushnell, Peter; Brill, Richard

    2014-02-01

    Atlantic sturgeon (Acipenser oxyrhynchus) populations have been declared either endangered or threatened under the U.S. Endangered Species Act. Effective measures to repel sturgeon from fishing gear would be beneficial to both fish and fishers because they could reduce both fishery-associated mortality and the need for seasonal and area closures of specific fisheries. Some chondrostean fishes (e.g., sturgeons and paddlefishes) can detect weak electric field gradients (possibly as low as 5 Μv/cm) due to arrays of electroreceptors (ampullae of Lorenzini) on their snout and gill covers. Weak electric fields, such as those produced by electropositive metals (typically mixtures of the lanthanide elements), could therefore potentially be used as a deterrent. To test this idea, we recorded the behavioral responses of juvenile Atlantic sturgeon (31-43 cm fork length) to electropositive metal (primarily a mixture of the lanthanide elements neodymium and praseodymium) both in the presence and absence of food stimuli. Trials were conducted in an approximately 2.5 m diameter × 0.3 m deep tank, and fish behaviors were recorded with an overhead digital video camera. Video records were subsequently digitized (x, y coordinate system), the distance between the fish and the electropositive metal calculated, and data summarized by compiling frequency distributions with 5-cm bins. Juvenile sturgeon showed clear avoidance of electropositive metal but only when food was present. On the basis of our results, we conclude that the electropositive metals, or other sources of weak electric fields, may eventually be used to reduce the interactions of Atlantic sturgeon with fishing gear, but further investigation is needed. © 2013 Society for Conservation Biology.

  9. Columbia Basin Fish and Wildlife Authority Project Abstracts; May 25-27, Portland, Oregon, 1997 Annual Review.

    Energy Technology Data Exchange (ETDEWEB)

    Allee, Brian J. (Columbia Basin Fish and Wildlife Authority, Portland, OR)

    1997-06-26

    Abstracts are presented from the 1997 Columbia Basin Fish and Wildlife Program Review of Projects. The purpose was to provide information and education on the approximate 127 million dollars in Northwest electric ratepayer fish and wildlife mitigation projects funded annually.

  10. Food and feeding habits of the african electric fish ( Mormyrus rume ...

    African Journals Online (AJOL)

    Mormyrus rume (Osteichthyes: Mormyridae) in Anambra river, Nigeria were studied from October, 2004 to March, 2006. Fish specimens were collected monthly at Otuocha and Ogurugu areas of Anambra River using hook and line, traps, gillnets and ...

  11. Coding conspecific identity and motion in the electric sense.

    Directory of Open Access Journals (Sweden)

    Na Yu

    Full Text Available Interactions among animals can result in complex sensory signals containing a variety of socially relevant information, including the number, identity, and relative motion of conspecifics. How the spatiotemporal properties of such evolving naturalistic signals are encoded is a key question in sensory neuroscience. Here, we present results from experiments and modeling that address this issue in the context of the electric sense, which combines the spatial aspects of vision and touch, with the temporal aspects of audition. Wave-type electric fish, such as the brown ghost knifefish, Apteronotus leptorhynchus, used in this study, are uniquely identified by the frequency of their electric organ discharge (EOD. Multiple beat frequencies arise from the superposition of the EODs of each fish. We record the natural electrical signals near the skin of a "receiving" fish that are produced by stationary and freely swimming conspecifics. Using spectral analysis, we find that the primary beats, and the secondary beats between them ("beats of beats", can be greatly influenced by fish swimming; the resulting motion produces low-frequency envelopes that broaden all the beat peaks and reshape the "noise floor". We assess the consequences of this motion on sensory coding using a model electroreceptor. We show that the primary and secondary beats are encoded in the afferent spike train, but that motion acts to degrade this encoding. We also simulate the response of a realistic population of receptors, and find that it can encode the motion envelope well, primarily due to the receptors with lower firing rates. We discuss the implications of our results for the identification of conspecifics through specific beat frequencies and its possible hindrance by active swimming.

  12. Why the short face? Developmental disintegration of the neurocranium drives convergent evolution in neotropical electric fishes.

    Science.gov (United States)

    Evans, Kory M; Waltz, Brandon; Tagliacollo, Victor; Chakrabarty, Prosanta; Albert, James S

    2017-03-01

    Convergent evolution is widely viewed as strong evidence for the influence of natural selection on the origin of phenotypic design. However, the emerging evo-devo synthesis has highlighted other processes that may bias and direct phenotypic evolution in the presence of environmental and genetic variation. Developmental biases on the production of phenotypic variation may channel the evolution of convergent forms by limiting the range of phenotypes produced during ontogeny. Here, we study the evolution and convergence of brachycephalic and dolichocephalic skull shapes among 133 species of Neotropical electric fishes (Gymnotiformes: Teleostei) and identify potential developmental biases on phenotypic evolution. We plot the ontogenetic trajectories of neurocranial phenotypes in 17 species and document developmental modularity between the face and braincase regions of the skull. We recover a significant relationship between developmental covariation and relative skull length and a significant relationship between developmental covariation and ontogenetic disparity. We demonstrate that modularity and integration bias the production of phenotypes along the brachycephalic and dolichocephalic skull axis and contribute to multiple, independent evolutionary transformations to highly brachycephalic and dolichocephalic skull morphologies.

  13. Systematics and biogeography of Sternarchellini (Gymnotiformes: Apteronotidae: Diversification of electric fishes in large Amazonian rivers

    Directory of Open Access Journals (Sweden)

    Stephen J. Ivanyisky III

    Full Text Available The Sternarchellini (Gymnotiformes, Apteronotidae is a clade of 10 electric fish species that inhabit deep river channels of the Amazon and Orinoco basins, attain moderate adult body sizes (15-50 cm TL, and have a predatory life style. Here we trace the evolutionary origin and diversification of Sternarchellini using standard phylogenetic and biogeographic procedures and a dataset of 70 morphological characters. The main results are: 1 the genus Sternarchellaincludes both species currently assigned to the genus Magosternarchus; and 2 neither of the multi-species assemblages of Sternarchellini in the Amazon and Orinoco basins are monophyletic. Historical biogeographic analysis suggests that sternarchelline evolution was linked to the large-scale river capture event that formed the modern Amazon and Orinoco basins, i.e. the Late Miocene rise of the Vaupes structural arch and concomitant breaching of the Purus structural arch. This event is hypothesized to have contributed to formation of the modern sternarchelline species, and to the formation of the modern basin-wide sternarchelline species assemblages. The results indicate that cladogenesis (speciation and anagenesis (adaptive evolution were decoupled processes in the evolution of Sternarchellini.

  14. Effectiveness of water release as mitigation for hydroelectric impacts to fish

    International Nuclear Information System (INIS)

    Lewis, A.F.; Mitchell, A.C.

    1995-01-01

    Utility companies release water to mitigate the effects of hydroelectric projects on fish habitats. Utility companies, government agencies, and research communities in Canada, the US, Europe, New Zealand, and Australia were surveyed as part of a Canadian Electrical Association study to evaluate the effectiveness of water release as a mitigation. Respondents identified only 28 projects in which water was released specifically to protect fish habitats. Fewer than half of these projects (12) were judged as being effective. Six case histories with preimpact assessment and postimpact monitoring were reviewed. In four cases fish habitat or fish populations or both were maintained; in two cases they were not. The effectiveness of water release differed among rivers and fish species, and was greatest when designed to meet the habitat requirements of each life-history stage. A review of the literature did not support the theory that a particular fraction of the mean annual flow provides the bet fish habitat. Although smaller changes in the flow regime had smaller effects, increasing minimum flows above those historically observed did not necessarily increase fish production

  15. Central control of cardiorespiratory interactions in fish.

    Science.gov (United States)

    Taylor, Edwin W; Leite, Cleo A C; Levings, Jennifer J

    2009-01-01

    Fish control the relative flow rates of water and blood over the gills in order to optimise respiratory gas exchange. As both flows are markedly pulsatile, close beat-to-beat relationships can be predicted. Cardiorespiratory interactions in fish are controlled primarily by activity in the parasympathetic nervous system that has its origin in cardiac vagal preganglionic neurons. Recordings of efferent activity in the cardiac vagus include units firing in respiration-related bursts. Bursts of electrical stimuli delivered peripherally to the cardiac vagus or centrally to respiratory branches of cranial nerves can recruit the heart over a range of frequencies. So, phasic, efferent activity in cardiac vagi, that in the intact fish are respiration-related, can cause heart rate to be modulated by the respiratory rhythm. In elasmobranch fishes this phasic activity seems to arise primarily from central feed-forward interactions with respiratory motor neurones that have overlapping distributions with cardiac neurons in the brainstem. In teleost fish, they arise from increased levels of efferent vagal activity arising from reflex stimulation of chemoreceptors and mechanoreceptors in the orobranchial cavity. However, these differences are largely a matter of emphasis as both groups show elements of feed-forward and feed-back control of cardiorespiratory interactions.

  16. Development of Solar Drying Model for Selected Cambodian Fish Species

    OpenAIRE

    Hubackova, Anna; Kucerova, Iva; Chrun, Rithy; Chaloupkova, Petra; Banout, Jan

    2014-01-01

    A solar drying was investigated as one of perspective techniques for fish processing in Cambodia. The solar drying was compared to conventional drying in electric oven. Five typical Cambodian fish species were selected for this study. Mean solar drying temperature and drying air relative humidity were 55.6°C and 19.9%, respectively. The overall solar dryer efficiency was 12.37%, which is typical for natural convection solar dryers. An average evaporative capacity of solar dryer was 0.049 kg·h...

  17. Use of electric and bubble barriers to limit the movement of Eurasian ruffe (Gymnocephalus cernuus)

    Science.gov (United States)

    Dawson, Heather A.; Reinhardt, Ulrich G.; Savino, Jacqueline F.

    2006-01-01

    Eurasian ruffe (Gymnocephalus cernuus) is an aquatic invasive species accidentally introduced via ballast water to the Great Lakes in the mid-1980s. Fish barrier technology is being studied to stop the spread of invasive fish species such as ruffe. Electrical barriers have been constructed, most notably in the Chicago Sanitary and Ship Canal, to prevent non-indigenous species such as ruffe from spreading into areas where they are currently absent. Information on the response of an invasive fish to barriers can help managers determine strategies to prevent the spread of these species via artificial waterways. In this laboratory study electrical barriers were set up to determine effectiveness of four electrical settings for repelling Eurasian ruffe measuring 10 cm or more in length. In separate tests, airbubble curtains with two bubble sizes and densities were created to test this type of barrier in blocking movement of ruffe less than 10 cm in length. The most effective electrical settings found (5 ms, 6 Hz) repelled only about half of the attempted passes. When ruffe were offered food or shelter on the opposite side of the electrical barrier, neither food-starved nor shelter-deprived ruffe made significantly more attempts to cross the barrier. Ruffe were significantly repelled by all air-bubble curtains, but a large proportion of passes (4.5 passes per fish on average in the treatments) were still observed. Electrical barrier settings and air-bubble curtains used in this study were found ineffective at completely blocking the movement, but somewhat effective at inhibiting the passage of ruffe.

  18. Microbiological spoilage of fish and fish products

    DEFF Research Database (Denmark)

    Gram, Lone; Huss, Hans Henrik

    1996-01-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative...... biochemical indicators of spoilage. Shewanzella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram......- positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish...

  19. Microbiological spoilage of fish and fish products.

    Science.gov (United States)

    Gram, L; Huss, H H

    1996-11-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative biochemical indicators of spoilage. Shewanella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram-positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish is well understood, much less is known about spoilage of lightly preserved fish products. It is concluded that the spoilage is probably caused by lactic acid bacteria, certain psychotrophic Enterobacteriaceae and/or Photobacterium phosphoreum. However, more work is needed in this area.

  20. Lindane residues in cultivated cucumber and in the most consumed fish in Caspian Sea (Iran).

    Science.gov (United States)

    Shokrzadeh, M; Saeedi Saravi, S S; Zehtab Yazdi, Y

    2009-09-01

    In this study, the concentrations of lindane residues (organochlorine pesticides) were analyzed in samples of cultivated cucumbers (Cucumis sativus L.) and four species of most consumed fish (Sefid, Koli, Kilca and Kafal fish). Samples of cucumber were collected from five sites in Sari city (north, south, east, west and central areas) and samples of fish were caught using electric fishing from four major fishing centers (Chalous and Babolsar cities, Khazar Abad and Miankaleh regions) in Mazandaran province of Iran. Quantitative determination of the lindane content was performed by gas chromatography electron-capture detection (GC-ECD). The results showed that the concentration of lindane in cucumber samples and in the dorsal muscle of the selected fish were less than the Food and Agriculture Organization/World Health Organization (FAO/WHO) recommended intake.

  1. Innovation in utilization of fish tanks for fish culture among fish ...

    African Journals Online (AJOL)

    This study investigated innovation in utilization of fish tanks for fish culture among fish farmers in Obio/Akpor Local Government Area of Rivers State, Nigeria. Data for this study was obtained through the administration of questionnaire and scheduled interview to 120 sampled fish farmers randomly selected from the study ...

  2. Fish health and fish quality

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian

    Aquaculture is an expanding worldwide industry producing an increasing amount of fish every year. The quality of the fish meat is dependent upon many biological and non-biological factors. Infectious diseases are known to cause bleedings and damage of the muscle tissue that may lead to scarring...... are poorly described in fish. The present work in this thesis focused on: 1) examination of potential changes in the quality regarding texture of the muscle tissue in rainbow trout (Oncorhynchus mykiss) after previous infection with the bacterial pathogens Yersinia ruckeri and Vibrio anguillarum; 2...... of these studies showed that previous infections by Yersinia ruckeri and Vibrio anguillarum gave rise to subsequent changes regarding textural quality parameters in fresh fish meat, while no differences were seen for cold-smoked meat from the same fish. The texture in previous infected fish was less flaky and less...

  3. Fish Synucleins: An Update

    Directory of Open Access Journals (Sweden)

    Mattia Toni

    2015-10-01

    Full Text Available Synucleins (syns are a family of proteins involved in several human neurodegenerative diseases and tumors. Since the first syn discovery in the brain of the electric ray Torpedo californica, members of the same family have been identified in all vertebrates and comparative studies have indicated that syn proteins are evolutionary conserved. No counterparts of syns were found in invertebrates suggesting that they are vertebrate-specific proteins. Molecular studies showed that the number of syn members varies among vertebrates. Three genes encode for α-, β- and γ-syn in mammals and birds. However, a variable number of syn genes and encoded proteins is expressed or predicted in fish depending on the species. Among biologically verified sequences, four syn genes were identified in fugu, encoding for α, β and two γ (γ1 and γ2 isoforms, whereas only three genes are expressed in zebrafish, which lacks α-syn gene. The list of “non verified” sequences is much longer and is often found in sequence databases. In this review we provide an overview of published papers and known syn sequences in agnathans and fish that are likely to impact future studies in this field. Indeed, fish models may play a key role in elucidating some of the molecular mechanisms involved in physiological and pathological functions of syn proteins.

  4. Fish oil quality of by-product (fish skin from swangi fish

    Directory of Open Access Journals (Sweden)

    La Ode Huli

    2015-01-01

    Full Text Available The skin of swangi fish is a potential fish skin to be produced for fish oil. The objectives of this research were aimed to determine the yield and the best quality of fish oil and also to compare fatty acid profile of the fish according to different extraction methods. Fish oil extractions were used by wet rendering method with extraction temperatures of 60, 70, 80, 90, 100°C for 20, 30, and 40 minutes. Fish oil quality was determined by the chemical oil characteristics i.e. PV, FFA, AV, anisidin, and TOTOX. Fatty acid profile was analyzed using gas chromatography (Shimadzu. The results of the study showed that the highest fish oil yield in each treatment was obtained extraction temperature of 60°C for 30 minutes with percentage of 0.33, (70°C for 30 minutes 0.46, (80°C for 30 minutes 1.23, (90°C for 20 minutes 1.14 and (100°C for 20 minutes 0.84. These values were lower compare to Bligh & Dyer and Soxhlet methods. Then, the best fish oil quality was resulted on temperature extraction of 60°C for 30 minutes with PV, FFA, anisidin, AV, and TOTOX were 9.17 meq/kg, 6.92%, 13,77 mg KOH/g, 0.86 meq/kg and 19.19 meq/kg, respectively. FUFA fatty acid compositions of swangi skin fish oil especially EPA and DHA in wet rendering method were gained 0.73% and 2.53%, respectively. These results were lower than Bligh & Dyer method which was consisted of 3.66% (EPA, and 13.29% (DHA and also Soxhlet extraction method with value of EPA was 2.78% and DHA was 9.62%.Keywords: EPA, extraction temperature, DHA, fish oil quality, fish skin

  5. Fishing down the largest coral reef fish species.

    Science.gov (United States)

    Fenner, Douglas

    2014-07-15

    Studies on remote, uninhabited, near-pristine reefs have revealed surprisingly large populations of large reef fish. Locations such as the northwestern Hawaiian Islands, northern Marianas Islands, Line Islands, U.S. remote Pacific Islands, Cocos-Keeling Atoll and Chagos archipelago have much higher reef fish biomass than islands and reefs near people. Much of the high biomass of most remote reef fish communities lies in the largest species, such as sharks, bumphead parrots, giant trevally, and humphead wrasse. Some, such as sharks and giant trevally, are apex predators, but others such as bumphead parrots and humphead wrasse, are not. At many locations, decreases in large reef fish species have been attributed to fishing. Fishing is well known to remove the largest fish first, and a quantitative measure of vulnerability to fishing indicates that large reef fish species are much more vulnerable to fishing than small fish. The removal of large reef fish by fishing parallels the extinction of terrestrial megafauna by early humans. However large reef fish have great value for various ecological roles and for reef tourism. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Evaluation of radioactivity concentrations from the Fukushima nuclear accident in fish products and associated risk to fish consumers

    International Nuclear Information System (INIS)

    Chen, J.

    2013-01-01

    Radioactive contamination of the Pacific Ocean following the Fukushima nuclear accident has raised public concerns about seafood safety(1, 2). Many people are wondering whether fish products from the Pacific Ocean and Japan are safe to eat 2 y after the accident. There is also some concern about seafood caught locally, outside of Japan. Based on monitoring data reported in July 2013, radioactive caesium concentrations in fish products from Fukushima and adjacent prefectures are evaluated. Resulting radiation doses from annual consumption at average contamination levels and occasional fish meals at much higher levels of caesium are calculated. To put radiation doses from caesium intake in perspective, comparisons are made to doses from naturally occurring radioactive polonium commonly found in fish. Discussion and conclusions are given subsequently. The Tokyo Electric Power Company has conducted routine radioactivity measurements ( 134 Cs and 137 Cs) of various marine fish and shellfish in the ocean area within a 20-km radius of the Fukushima Daiichi Nuclear Power Station (FDNPS). Based on their posted summary on 16 August 2013(3), a total of 100 fish samples were collected from 7 to 23 July, offshore of the FDNPS and outside of its port area. The nuclide analysis report showed that 134 Cs was detected in 64 samples with concentrations varying from 3.5 to 130 Bq kg -1 . 137 Cs was detected in 79 samples and the concentration varied from 3.6 to 260 Bq kg -1 . On average, fish and shellfish caught within 20-km offshore of the FDNPS contain 12 Bq kg -1 of 134 Cs and 26 Bq kg -1 of 137 Cs. The Japanese Fisheries Agency (JFA), in cooperation with the relevant prefectural governments and organisations, has conducted sampling and inspections of fishery products at the major fishing ports in Fukushima and adjacent prefectures on a weekly basis to examine the possible contamination of fishery products by radioactive materials released from the FDNPS. (authors)

  7. Effects of offshore wind power on the pelagic fish; Effekter av havsbaserad vindkraft paa pelagisk fisk

    Energy Technology Data Exchange (ETDEWEB)

    Axenrot, Thomas (SLU, Institutionen foer Akvatiska Resurser, Soetvattenlaboratoriet (Sweden)); Didrikas, Tomas (AquaBiota Water Research AB (Sweden); Stockholms universitet (Sweden))

    2012-02-15

    Marine wind parks are being planned for and built in coastal and shallow offshore areas in response to an increasing demand for renewable energy. Today's knowledge is limited about possible effects on fish from habitat change and generated underwater sound when wind parks are running. There may also be consequences for the fishery. Studies on fish hearing have shown that many fishes hear low frequency sound like that produced by wind turbines. This study consists of two parts. The first part of the study investigated pelagic fish abundance and spatial distribution at one wind park and two reference areas (200 m to 10 km distance from fundaments) at five different occasions from 2005 through 2007 in the Kalmar Sound of the Baltic Sea. The highest fish densities was found in the most remote reference area. The difference between areas was statistically significant for fish of the size groups 30-80 mm (stickleback), 80-140 mm (sprat, small herring) and 140-250 mm (adult herring). For fish >250 mm, representing cod and salmon, no statistically significant difference between areas was observed. For one group (sticklebacks) Area was significantly pointed out as the most important factor for the observed differences in fish density. No data on fish densities in the investigated areas were collected before the wind park (Utgrunden 1) was built which is a drawback to this part of the study. The second part of the study focused on possible effects of underwater sound generated by wind turbines on fish behaviour in the close vicinity of the fundaments (2-35 m distance). Stationary horizontal acoustics was used to estimate fish abundance and swimming speed in relation to turbine rotor speed and electricity production. The changes of abundance were not consistent and difficult to interpret. Fish swimming speed decreased with increasing turbine rotor speed and electricity production. However, it cannot be distinguished if this was an effect of sound emitted by wind turbines

  8. Innovative water withdrawal system re-establishes fish migration runs

    International Nuclear Information System (INIS)

    Anon.

    2008-01-01

    This article described a unique water withdrawal and fish bypass structure that is under construction in Oregon to re-establish anadromous fish runs and to improve water quality downstream of the Round Butte dam. Portland General Electric and the Confederated Tribes of the Warm Springs Reservation, which co-own the dam, have committed to re-establish fish runs in response to concerns over the declining numbers of salmon and trout in the region. Water intakes are routinely added at hydroelectric facilities to protect native fish in compliance with the Federal Energy Regulatory Commission and the Clean Water Act. The Round Butte Hydroelectric project had a complex set of challenges whereby surface-current directions had to be changed to help migrating salmon swim easily into a fish handling area and create a fish collection system. CH2M HILL designed the system which consists of a large floating structure, an access bridge, a large vertical conduit and a base structure resting on the lake bed. Instead of using 2D CAD file methods, CH2M HILL decided to take advantage of 3D models to visualize the complex geometry of these structures. The 3D models were used to help designers and consultants understand the issues, resolve conflicts and design solutions. The objective is to have the system operating by the 2009 migrating season. 1 ref., 4 figs

  9. Strontium-90 and cesium-137 in fresh-water fish; April, 1977 to March, 1978

    International Nuclear Information System (INIS)

    1979-01-01

    Each sample is washed in water and wiped with filter paper. Only the estable portion is used in case of a large-sized fish, and the whole is used in case of a small fish. Each is weighed, placed on a stainless pan or porcelain dish, carbonized and further ashed in an electric oven. The results obtained from April 1977 to March 1978 were shown in a table. (J.P.N.)

  10. Alexander von Humboldt: galvanism, animal electricity, and self-experimentation part 2: the electric eel, animal electricity, and later years.

    Science.gov (United States)

    Finger, Stanley; Piccolino, Marco; Stahnisch, Frank W

    2013-01-01

    After extensive experimentation during the 1790s, Alexander von Humboldt remained skeptical about "animal electricity" (and metallic electricity), writing instead about an ill-defined galvanic force. With his worldview and wishing to learn more, he studied electric eels in South America just as the new century began, again using his body as a scientific instrument in many of his experiments. As had been the case in the past and for many of the same reasons, some of his findings with the electric eel (and soon after, Italian torpedoes) seemed to argue against biological electricity. But he no longer used galvanic terminology when describing his electric fish experiments. The fact that he now wrote about animal electricity rather than a different "galvanic" force owed much to Alessandro Volta, who had come forth with his "pile" (battery) for multipling the physical and perceptable effects of otherwise weak electricity in 1800, while Humboldt was deep in South America. Humboldt probably read about and saw voltaic batteries in the United States in 1804, but the time he spent with Volta in 1805 was probably more significant in his conversion from a galvanic to an electrical framework for understanding nerve and muscle physiology. Although he did not continue his animal electricity research program after this time, Humboldt retained his worldview of a unified nature and continued to believe in intrinsic animal electricity. He also served as a patron to some of the most important figures in the new field of electrophysiology (e.g., Hermann Helmholtz and Emil du Bois-Reymond), helping to take the research that he had participated in to the next level.

  11. A new signal development process and sound system for diverting fish from water intakes

    International Nuclear Information System (INIS)

    Klinet, D.A.; Loeffelman, P.H.; van Hassel, J.H.

    1992-01-01

    This paper reports that American Electric Power Service Corporation has explored the feasibility of using a patented signal development process and underwater sound system to divert fish away from water intake areas. The effect of water intakes on fish is being closely scrutinized as hydropower projects are re-licensed. The overall goal of this four-year research project was to develop an underwater guidance system which is biologically effective, reliable and cost-effective compared to other proposed methods of diversion, such as physical screens. Because different fish species have various listening ranges, it was essential to the success of this experiment that the sound system have a great amount of flexibility. Assuming a fish's sounds are heard by the same kind of fish, it was necessary to develop a procedure and acquire instrumentation to properly analyze the sounds that the target fish species create to communicate and any artificial signals being generated for diversion

  12. Fish welfare: Fish capacity to experience pain

    Directory of Open Access Journals (Sweden)

    Vučinić Marijana

    2009-01-01

    Full Text Available Teleost fish possess similar nociceptive processing systems to those found in terrestrial vertebrates. It means that they react to potential painful stimuli in a similar manner as mammals and birds. However, the welfare of fish has been the focus of less research than that of higher vertebrates. Humans may affect the welfare of fish through fisheries, aquaculture and a number of other activities. There is scientific evidence to support the assumption that fish have the capacity to experience pain because they possess functional nociceptors, endogenous opioids and opioid receptors, brain structures involved in pain processing and pathways leading from nociceptors to higher brain structures. Also, it is well documented that some anaesthetics and analgesics may reduce nociceptive responses in fish. Behavioural indicators in fish such as lip-rubbing and rocking behaviours are the best proof that fish react to potential painful stimuli. This paper is an overview of some scientific evidence on fish capacity to experience pain.

  13. Fish-allergic patients may be able to eat fish.

    Science.gov (United States)

    Mourad, Ahmad A; Bahna, Sami L

    2015-03-01

    Reported fish allergy prevalence varies widely, with an estimated prevalence of 0.2% in the general population. Sensitization to fish can occur by ingestion, skin contact or inhalation. The manifestations can be IgE or non-IgE mediated. Several fish allergens have been identified, with parvalbumins being the major allergen in various species. Allergenicity varies among fish species and is affected by processing or preparation methods. Adverse reactions after eating fish are often claimed to be 'allergy' but could be a reaction to hidden food allergen, fish parasite, fish toxins or histamine in spoiled fish. Identifying such causes would allow free consumption of fish. Correct diagnosis of fish allergy, including the specific species, might provide the patient with safe alternatives. Patients have been generally advised for strict universal avoidance of fish. However, testing with various fish species or preparations might identify one or more forms that can be tolerated.

  14. Fish Allergy

    Science.gov (United States)

    ... Cause Blog Vision Awards Common Allergens Fish Allergy Fish Allergy Learn about fish allergy, how to read ... that you must avoid both. Allergic Reactions to Fish Finned fish can cause severe and potentially life- ...

  15. Performance of Azolla caroliniana Willd. and Salvinia auriculata Aubl. on fish farming effluent.

    Science.gov (United States)

    Toledo, J J; Penha, J

    2011-02-01

    The increasing release of untreated fish farming effluents into water courses that flow to the Pantanal wetlands in Mato Grosso (Brazil) may drive this ecosystem to eutrophication. Therefore, the growth of Azolla caroliniana Willd. and Salvinia auriculata Aubl. in fish farming effluent and their effect on its quality were evaluated for 48 days in a greenhouse. The results were compared to those obtained in a nutrient rich solution (Hoagland ½ medium). Azolla caroliniana showed lower relative growth rate in fish farming effluent (0.020 d-1) than in Hoagland ½ medium (0.029 d-1). However, S. auriculata grew slightly better in fish farming effluent (0.030 d-1) than in Hoagland ½ medium (0.025 d-1). The species apparently contributed to reduce nitrate and phosphate concentration in Hoagland ½ medium. However, in fish farming effluent, only electrical conductivity and pH were reduced by plants compared to the control without plants. Thus, A. caroliniana and S. auriculata show low potential for improving effluent quality.

  16. Improved intake design for downstream migrating fish at hydropower plants

    International Nuclear Information System (INIS)

    Mih, W.C.

    1991-01-01

    This paper reports on hydroelectric power projects on the Columbia River which provided low-cost electricity to the Pacific Northwest. However, they are detrimental to anadromous fisheries resources. Anadromous fish are migratory. They begin their life in shallow mountain streams. After several months, they migrate to the ocean, where the fish grow to maturity before their return migration. Remarkably, most anadromous fish return to spawn in their natal streams. At dams, the upstream migration of grown salmon and steelhead is accomplished through fishways. The downstream migration of juveniles remains a serious problem. Juvenile fish follow the water flow during their sea-ward migration. When passing through a turbine, fish can be severely injured due to the sudden pressure drop, high velocity shear zones, and rotating turbine blades. Stunned fish that survive the gauntlet of the turbine are easy prey for sea gulls and squawfish in the tailrace of the powerhouse. Fish mortality per turbine passage is estimated at 15 percent. With nine hydropower projected on the main steam of the Columbia River, their combined mortality is very serious. The historical Columbia River anadromous run of about 12 million fish has declined to 2.5 million in recent years. Modern high-output hydraulic turbines are designed to be placed at a lower elevation to minimize cavitation damage to turbine blades. The modern design trend of deep intake submergence has caused parallel and unsteady vortex flow patterns in the forebay, resulting in a decrease in the guiding efficiency of the screens, such as at Bonneville Second Powerhouse and at Rocky Reach Project

  17. Reproductive Ecology of Prochilodus brevis an Endemic Fish from the Semiarid Region of Brazil

    Directory of Open Access Journals (Sweden)

    Liliane de Lima Gurgel

    2012-01-01

    Full Text Available The commercially important migratory fish Prochilodus brevis is from the Neotropical region, and understanding the reproductive ecology of this potamodromous fish is essential for its conservation and management. This study investigated the length-mass relationship, sex ratio, length at first gonadal maturity, gonadal development stages, gonadosomatic index, condition factor, and reproductive period of P. brevis. Temporal distribution of rainfall, temperature, dissolved oxygen concentration, pH, and electrical conductivity of the water were related to the reproductive period of this fish. Rainfall seems to be the main environmental factor which modulates changes in limnological parameters and the timing of the spawning period of this fish. P. brevis migrates into lower reaches of the river to feed during the dry season and returns to the upper reaches during the rainy season to spawn. Inadequate facilities for migration create obstacles for spawning success of this ecologically important fish.

  18. Electrical stimulation in exercise training

    Science.gov (United States)

    Kroll, Walter

    1994-01-01

    Electrical stimulation has a long history of use in medicine dating back to 46 A.D. when the Roman physician Largus found the electrical discharge of torpedo fishes useful in the treatment of pain produced by headache and gout. A rival Greek physician, Dioscorides, discounted the value of the torpedo fish for headache relief but did recommend its use in the treatment of hemorrhoids. In 1745, the Leyden jar and various sized electrostatic generators were used to treat angina pectoris, epilepsy, hemiplegia, kidney stones, and sciatica. Benjamin Franklin used an electrical device to treat successfully a young woman suffering from convulsive fits. In the late 1800's battery powered hydroelectric baths were used to treat chronic inflammation of the uterus while electrified athletic supporters were advertised for the treatment of male problems. Fortunately, such an amusing early history of the simple beginnings of electrical stimulation did not prevent eventual development of a variety of useful therapeutic and rehabilitative applications of electrical stimulation. Over the centuries electrical stimulation has survived as a modality in the treatment of various medical disorders with its primary application being in the rehabilitation area. Recently, a surge of new interest in electrical stimulation has been kindled by the work of a Russian sport scientist who reported remarkable muscle strength and endurance improvements in elite athletes. Yakov Kots reported his research on electric stimulation and strength improvements in 1977 at a Canadian-Soviet Exchange Symposium held at Concordia University in Montreal. Since then an explosion of new studies has been seen in both sport science and in medicine. Based upon the reported works of Kots and the present surge of new investigations, one could be misled as to the origin of electrical stimulation as a technique to increase muscle strength. As a matter of fact, electric stimulation has been used as a technique to improve

  19. What fish and how many there are in Danube Delta?

    Directory of Open Access Journals (Sweden)

    NĂVODARU Ion

    2011-09-01

    Full Text Available The real figure of fish fauna and fishery of the Danube delta is difficult to be estimated due to the limitation in fish sampling and underreporting of catch. This paper proposes to compare output of fish sampling with commercial catch statistics. Fish fauna from Danube delta complex lakes was sampled in 2006-2008 period and catchstatistics represent a long time series data recording. For fish sampling was used two complementary methods: electric fishing for shallow border zone and Nordic gillnet fishing for deep open water. The frequency of occurrence and the dominance in abundance analysis was based on 267 samples including 57158 individuals from both sampling methods since the dominance in biomass was based on 640 kg of fish only from gillnet sampling. In total was sampled 40 fish species, while catch statistics recorded 10 commercial species plus more 3 categories that include more other different species. In the sampling analysis, the most frequent species (very frequent were perch, bleak, roach, rudd and white bream. The most abundant(eudominant and dominant species were bleak, roach, rudd, perch, and white bream. In biomass dominate (eudominant and dominant roach, rudd, perch, white bream, bleak, gibel carp and pike. This analysis shows that Danube delta lakes are dominate by small eurytopic and opportunistic species, favoured by eutrophication of lakes. However, this figure is expression of sampling methods that are limited in estimation of real fish population status. Nevertheless, when this structure is compared to commercial statistics, it is noticed completely other figure. The difference in fish structure may be explained by targeting fishing to large size and high market value fish species. It is not neglected that commercial statistics is deformed by unreported catch sold on black market. According with recorded statistics from 1920 until 2010 the catch trend continuously decrease and species composition was well balanced before

  20. Strontium-90 and cesium-137 in freshwater fish (from Jul. 1984 to Dec. 1984)

    International Nuclear Information System (INIS)

    1984-01-01

    Sr-90 and Cs-137 in freshwater fish were determined using radiochemical analysis. Three species of fish (Cyprinus carpio, Carassius auratus, and Hypomesus transpacificus nipponensis) were collected during the fishing season from eight sampling locations. Only the edible part was used in case of larger sized fish, and the whole part was used in case of smaller ones. Each sample was weighed and placed in a stainless steel pan or a porcelain dish. After carbonized, the sample was ashed in an electric muffle furnace. The maximum value of Sr-90 was 96 +- 1.7 pCi/kg in Cyprinus carpio collected from Akita in July 1984; and that of Cs-137 was 11 +- 0.7 pCi/kg in Carassius auratus from Fukui in December 1984. (Namekawa, K.)

  1. 49 CFR 173.218 - Fish meal or fish scrap.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Fish meal or fish scrap. 173.218 Section 173.218... Fish meal or fish scrap. (a) Except as provided in Column (7) of the HMT in § 172.101 of this subchapter, fish meal or fish scrap, containing at least 6%, but not more than 12% water, is authorized for...

  2. Fish Ontology framework for taxonomy-based fish recognition

    Science.gov (United States)

    Ali, Najib M.; Khan, Haris A.; Then, Amy Y-Hui; Ving Ching, Chong; Gaur, Manas

    2017-01-01

    Life science ontologies play an important role in Semantic Web. Given the diversity in fish species and the associated wealth of information, it is imperative to develop an ontology capable of linking and integrating this information in an automated fashion. As such, we introduce the Fish Ontology (FO), an automated classification architecture of existing fish taxa which provides taxonomic information on unknown fish based on metadata restrictions. It is designed to support knowledge discovery, provide semantic annotation of fish and fisheries resources, data integration, and information retrieval. Automated classification for unknown specimens is a unique feature that currently does not appear to exist in other known ontologies. Examples of automated classification for major groups of fish are demonstrated, showing the inferred information by introducing several restrictions at the species or specimen level. The current version of FO has 1,830 classes, includes widely used fisheries terminology, and models major aspects of fish taxonomy, grouping, and character. With more than 30,000 known fish species globally, the FO will be an indispensable tool for fish scientists and other interested users. PMID:28929028

  3. Fish Ontology framework for taxonomy-based fish recognition

    Directory of Open Access Journals (Sweden)

    Najib M. Ali

    2017-09-01

    Full Text Available Life science ontologies play an important role in Semantic Web. Given the diversity in fish species and the associated wealth of information, it is imperative to develop an ontology capable of linking and integrating this information in an automated fashion. As such, we introduce the Fish Ontology (FO, an automated classification architecture of existing fish taxa which provides taxonomic information on unknown fish based on metadata restrictions. It is designed to support knowledge discovery, provide semantic annotation of fish and fisheries resources, data integration, and information retrieval. Automated classification for unknown specimens is a unique feature that currently does not appear to exist in other known ontologies. Examples of automated classification for major groups of fish are demonstrated, showing the inferred information by introducing several restrictions at the species or specimen level. The current version of FO has 1,830 classes, includes widely used fisheries terminology, and models major aspects of fish taxonomy, grouping, and character. With more than 30,000 known fish species globally, the FO will be an indispensable tool for fish scientists and other interested users.

  4. Entrainment, retention, and transport of freely swimming fish in junction gaps between commercial barges operating on the Illinois Waterway

    Science.gov (United States)

    Davis, Jeremiah J.; Jackson, P. Ryan; Engel, Frank; LeRoy, Jessica Z.; Neeley, Rebecca N.; Finney, Samuel T.; Murphy, Elizabeth A.

    2016-01-01

    Large Electric Dispersal Barriers were constructed in the Chicago Sanitary and Ship Canal (CSSC) to prevent the transfer of invasive fish species between the Mississippi River Basin and the Great Lakes Basin while simultaneously allowing the passage of commercial barge traffic. We investigated the potential for entrainment, retention, and transport of freely swimming fish within large gaps (> 50 m3) created at junction points between barges. Modified mark and capture trials were employed to assess fish entrainment, retention, and transport by barge tows. A multi-beam sonar system enabled estimation of fish abundance within barge junction gaps. Barges were also instrumented with acoustic Doppler velocity meters to map the velocity distribution in the water surrounding the barge and in the gap formed at the junction of two barges. Results indicate that the water inside the gap can move upstream with a barge tow at speeds near the barge tow travel speed. Water within 1 m to the side of the barge junction gaps was observed to move upstream with the barge tow. Observed transverse and vertical water velocities suggest pathways by which fish may potentially be entrained into barge junction gaps. Results of mark and capture trials provide direct evidence that small fish can become entrained by barges, retained within junction gaps, and transported over distances of at least 15.5 km. Fish entrained within the barge junction gap were retained in that space as the barge tow transited through locks and the Electric Dispersal Barriers, which would be expected to impede fish movement upstream.

  5. Design and dynamic modeling of electrorheological fluid-based variable-stiffness fin for robotic fish

    Science.gov (United States)

    Bazaz Behbahani, Sanaz; Tan, Xiaobo

    2017-08-01

    Fish actively control their stiffness in different swimming conditions. Inspired by such an adaptive behavior, in this paper we study the design, prototyping, and dynamic modeling of compact, tunable-stiffness fins for robotic fish, where electrorheological (ER) fluid serves as the enabling element. A multi-layer composite fin with an ER fluid core is prototyped and utilized to investigate the influence of electrical field on its performance. Hamilton's principle is used to derive the dynamic equations of motion of the flexible fin, and Lighthill's large-amplitude elongated-body theory is adopted to estimate the hydrodynamic force when the fin undergoes base-actuated rotation. The dynamic equations are then discretized using the finite element method, to obtain an approximate numerical solution. Experiments are conducted on the prototyped flexible ER fluid-filled beam for parameter identification and validation of the proposed model, and for examining the effectiveness of electrically controlled stiffness tuning. In particular, it is found that the natural frequency is increased by almost 40% when the applied electric field changes from 0 to 1.5× {10}6 {{V}} {{{m}}}-1.

  6. Do bacteria, not fish, produce 'fish kairomone'?

    NARCIS (Netherlands)

    Ringelberg, J.; Van Gool, E.

    1998-01-01

    Fish-associated chemicals enhance phototactic downward swimming in Daphnia. If perch were treated with the antibiotic ampicillin, this enhancement was significantly decreased. Therefore, not fish, but bacteria associated with fish, seem to produce this kairomone. [KEYWORDS: Diel vertical migration;

  7. Adoption Of Improved Fish Technologies Among Fish Farmers In ...

    African Journals Online (AJOL)

    A shortfall exists between fish supply and fish demand in the country despite the introduction of improved technology to fish farmers. This led to huge wage bill on the importation of fish to meet the protein need of the ever increasing population. This prompted this study with focus on adoption of improved fish technologies ...

  8. Which Fish Should I Eat? Perspectives Influencing Fish Consumption Choices

    Science.gov (United States)

    Choi, Anna L.; Karagas, Margaret R.; Mariën, Koenraad; Rheinberger, Christoph M.; Schoeny, Rita; Sunderland, Elsie; Korrick, Susan

    2012-01-01

    Background: Diverse perspectives have influenced fish consumption choices. Objectives: We summarized the issue of fish consumption choice from toxicological, nutritional, ecological, and economic points of view; identified areas of overlap and disagreement among these viewpoints; and reviewed effects of previous fish consumption advisories. Methods: We reviewed published scientific literature, public health guidelines, and advisories related to fish consumption, focusing on advisories targeted at U.S. populations. However, our conclusions apply to groups having similar fish consumption patterns. Discussion: There are many possible combinations of matters related to fish consumption, but few, if any, fish consumption patterns optimize all domains. Fish provides a rich source of protein and other nutrients, but because of contamination by methylmercury and other toxicants, higher fish intake often leads to greater toxicant exposure. Furthermore, stocks of wild fish are not adequate to meet the nutrient demands of the growing world population, and fish consumption choices also have a broad economic impact on the fishing industry. Most guidance does not account for ecological and economic impacts of different fish consumption choices. Conclusion: Despite the relative lack of information integrating the health, ecological, and economic impacts of different fish choices, clear and simple guidance is necessary to effect desired changes. Thus, more comprehensive advice can be developed to describe the multiple impacts of fish consumption. In addition, policy and fishery management inter-ventions will be necessary to ensure long-term availability of fish as an important source of human nutrition. PMID:22534056

  9. Bioaccumulation of methylmercury in fish tissue from the Roosevelt River, Southwestern Amazon basin

    Directory of Open Access Journals (Sweden)

    Marcelo Rodrigues dos Anjos

    2016-06-01

    Full Text Available Mercury is a major pollutant in the Amazon River system, and its levels in fish and human hair are usually above the limit recommended by health agencies. The objective of this study was to analyze the methylmercury (MeHg concentration in fish tissue from the Roosevelt River. The river's water velocity, depth, pH, temperature, electrical conductivity, dissolved oxygen and substrate type were measured, and fifty specimens distributed in 14 fish species were collected. A total of 64.3% of the sampled species were of the order Characiform and 71.4% of the species were carnivores. Fifty percent of the species had MeHg concentrations above threshold limit (Hg-T 0.5 mg kg-1 established for food by the World Health Organization. Cichla monoculus had the highest value of MeHg (2.45 mg kg-1. The MeHg concentration in fish varied according to dietary habits. The study also found bioaccumulation of MeHg in fish tissue in the following descending order: carnivorous > detritivorous > frugivore. Low significant correlations were found between fish weight or length and MeHg. Further studies on MeHg contamination are recommended in tissues of fish consumed in human riverine communities in the Roosevelt River Basin.

  10. Fish Rhabdoviruses

    Science.gov (United States)

    Kurath, G.; Winton, J.

    2008-01-01

    Many important viral pathogens of fish are members of the family Rhabdoviridae. The viruses in this large group cause significant losses in populations of wild fish as well as among fish reared in aquaculture. Fish rhabdoviruses often have a wide host and geographic range, and infect aquatic animals in both freshwater and seawater. The fish rhabdoviruses comprise a diverse collection of isolates that can be placed in one of two quite different groups: isolates that are members of the established genusNovirhabdovirus, and those that are most similar to members of the genus Vesiculovirus. Because the diseases caused by fish rhabdoviruses are important to aquaculture, diagnostic methods for their detection and identification are well established. In addition to regulations designed to reduce the spread of fish viruses, a significant body of research has addressed methods for the control or prevention of diseases caused by fish rhabdoviruses, including vaccination. The number of reported fish rhabdoviruses continues to grow as a result of the expansion of aquaculture, the increase in global trade, the development of improved diagnostic methods, and heightened surveillance activities. Fish rhabdoviruses serve as useful components of model systems to study vertebrate virus disease, epidemiology, and immunology.

  11. Fish for Feed vs Fish for Food

    OpenAIRE

    Allan, Geoff L.

    2004-01-01

    Aquaculture is the fastest-growing food producing industry sector in the world. Demand for feed ingredients, particularly for preferred protein sources such as fishmeal, fish oil and ‘trash fish’, has also increased, raising questions about sustainability and uses of fish for aquaculture feeds or directly as human food. Approximately 30 million metric tonnes (MMT) of fish from capture fisheries are used each year to produce fishmeal and fish oil. The species used are not usually consumed dire...

  12. Fish Allergy

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Fish Allergy KidsHealth / For Parents / Fish Allergy What's in this ... Print en español Alergia al pescado About Fish Allergy A fish allergy is not exactly the same ...

  13. Strontium-90 and cesium-137 in sea fish (from Nov. 1984 to Jun. 1985)

    International Nuclear Information System (INIS)

    1985-01-01

    Sr-90 and Cs-137 in sea fish were determined using radiochemical analysis. Seven species of fish (Branchiostegus sp., Katsuwonus pelamis, Limanda herzensteini, Sillago sihama, Scomber japonicus, Caesio chrysozonus cuvier, and Sebastes Inermis) were collected during the fishing season from nine sampling locations. Only the edible part was used in cases of larger sized fish, and the whole part was used in cases of smaller ones. Each sample was weighed and placed in a stainless steel pan or a porcelain dish. After carbonization, the sample was ashed in an electric muffle furnace. The maximum value of Sr-90 was 0.9 +- 0.26 pCi/kg in Limanda herzensteini collected from Hiroshima in March 1985; and that of Cs-137 was 12 +- 0.5 pCi/kg in Katsuwonus pelamis collected from Kochi in May 1985. (Namekawa, K.)

  14. Strontium-90 and cesium-137 in sea fish from Nov. 1983 to Jun. 1984

    International Nuclear Information System (INIS)

    1984-01-01

    Sr-90 and Cs-137 in sea fish were determined using radiochemical analysis. Seven species of fish (Branchiostegus sp., Katsuwonus pelamis, Limanda herzensteini, Sillago sihama, Pneumatophorus japonicus, Caesio chrysozonus cuvier, and Sebastes Inermis) were collected during the fishing season from 8 sampling locations. Only the edible part was used in case of larger sized fish, and the whole part was used in case of smaller ones. Each sample was weighed and placed in a stainless steel pan or a porcelain dish. After carbonized, the sample was ashed in an electric muffle furnace. The maximum values of Sr-90 was 1.0+-0.25 pCi/kg in Sebastes Inermis collected from Yamaguchi in April 1984; the maximum value of Cs-137 was 14.0+-0.60 pCi/kg in Katsuwonus pelamis collected from Kochi in May 1984. (Namekawa, K.)

  15. Performance of Azolla caroliniana Willd. and Salvinia auriculata Aubl. on fish farming effluent

    Directory of Open Access Journals (Sweden)

    JJ. Toledo

    Full Text Available The increasing release of untreated fish farming effluents into water courses that flow to the Pantanal wetlands in Mato Grosso (Brazil may drive this ecosystem to eutrophication. Therefore, the growth of Azolla caroliniana Willd. and Salvinia auriculata Aubl. in fish farming effluent and their effect on its quality were evaluated for 48 days in a greenhouse. The results were compared to those obtained in a nutrient rich solution (Hoagland ½ medium. Azolla caroliniana showed lower relative growth rate in fish farming effluent (0.020 d-1 than in Hoagland ½ medium (0.029 d-1. However, S. auriculata grew slightly better in fish farming effluent (0.030 d-1 than in Hoagland ½ medium (0.025 d-1. The species apparently contributed to reduce nitrate and phosphate concentration in Hoagland ½ medium. However, in fish farming effluent, only electrical conductivity and pH were reduced by plants compared to the control without plants. Thus, A. caroliniana and S. auriculata show low potential for improving effluent quality.

  16. Cell Proliferation, Migration, and Neurogenesis in the Adult Brain of the Pulse Type Weakly Electric Fish, Gymnotus omarorum

    Directory of Open Access Journals (Sweden)

    Valentina Olivera-Pasilio

    2017-08-01

    Full Text Available Adult neurogenesis, an essential mechanism of brain plasticity, enables brain development along postnatal life, constant addition of new neurons, neuronal turnover, and/or regeneration. It is amply distributed but negatively modulated during development and along evolution. Widespread cell proliferation, high neurogenic, and regenerative capacities are considered characteristics of teleost brains during adulthood. These anamniotes are promising models to depict factors that modulate cell proliferation, migration, and neurogenesis, and might be intervened to promote brain plasticity in mammals. Nevertheless, the migration path of derived cells to their final destination was not studied in various teleosts, including most weakly electric fish. In this group adult brain morphology is attributed to sensory specialization, involving the concerted evolution of peripheral electroreceptors and electric organs, encompassed by the evolution of neural networks involved in electrosensory information processing. In wave type gymnotids adult brain morphology is proposed to result from lifelong region specific cell proliferation and neurogenesis. Consistently, pulse type weakly electric gymnotids and mormyrids show widespread distribution of proliferation zones that persists in adulthood, but their neurogenic potential is still unknown. Here we studied the migration process and differentiation of newborn cells into the neuronal phenotype in the pulse type gymnotid Gymnotus omarorum. Pulse labeling of S-phase cells with 5-Chloro-2′-deoxyuridine thymidine followed by 1 to 180 day survivals evidenced long distance migration of newborn cells from the rostralmost telencephalic ventricle to the olfactory bulb, and between layers of all cerebellar divisions. Shorter migration appeared in the tectum opticum and torus semicircularis. In many brain regions, derived cells expressed early neuronal markers doublecortin (chase: 1–30 days and HuC/HuD (chase: 7–180 days

  17. Impingement and entrainment of fishes at the Savannah River Plant: an NPDES 316b demonstration

    International Nuclear Information System (INIS)

    McFarlane, R.W.; Frietsche, R.F.; Miracle, R.D.

    1978-02-01

    Environmental impacts of the Savannah River Plant's withdrawal of Savannah River water include impingement of juvenile and adult fish on trash removal screens, and entrainment of planktonic fish eggs and larval fish into the pumping system. The Savannah River Plant (SRP) has the capacity to pump 3.6 million cubic meters of water per day--25% of the minimal river discharge--for cooling and other purposes. Present removal is 7% of the actual river discharge. In the river and intake canals reside sixty-nine species of fishes. The species composition of the resident fish community of the intake canals is similar to the species composition in the river, but different in relative species abundance. The dominant sunfishes tend to reside in the canals for long periods and seldom go from canal to canal. The fish impingement rate at the plant ranks very low in comparison with electric power plants on inland waters. Thirty-five species of fishes were impinged during 1977. The average impingement rate of 7.3 fish per day extrapolates to 2,680 fish per year. No single species comprised more than 10% of the sample. The most commonly impinged species were bluespotted sunfish, warmouth, channel catfish, and yellow perch. The relative abundance of those species impinged deviates from their relative abundance in the canal fish population

  18. Fish consumption and track to a fish feed formulation

    Science.gov (United States)

    Cai-Juan, Soong; Ramli, Razamin; Rahman, Rosshairy Abdul

    2015-12-01

    Strategically located in the equator, Malaysia is blessed with plenty of fish supply. The high demand in fish consumption has helped the development in the fishery industry and provided numerous jobs in the secondary sector, contributing significantly to the nation's income. A survey was conducted to understand the trend of current demands for fish for the purpose of designing a feed formulation, which is still limited in this area of study. Results showed that grouper fish in restaurants commanded a very high price compared to other species of fish. Tiger grouper gained the highest demand in most restaurants, while giant grouper had the highest price in restaurants. Due to the demand and challenges to culture this type of fish, a framework for fish feed formulation is proposed. The formulation framework when materialized could be an alternative to the use of trash fish as the feed for grouper.

  19. 75 FR 6058 - Federal Sport Fish Restoration; California Department of Fish and Game Fish Hatchery and Stocking...

    Science.gov (United States)

    2010-02-05

    ...] Federal Sport Fish Restoration; California Department of Fish and Game Fish Hatchery and Stocking Program... (NEPA) of 1969, as amended, for the EIR/EIS jointly prepared with CDFG. Under the Sport Fish Restoration... has authority to grant Federal funds from the Sport Fish Restoration and Boating Trust Fund to support...

  20. Relative and combined effects of habitat and fishing on reef fish communities across a limited fishing gradient at Ningaloo.

    Science.gov (United States)

    Wilson, Shaun K; Babcock, Russ C; Fisher, Rebecca; Holmes, Thomas H; Moore, James A Y; Thomson, Damian P

    2012-10-01

    Habitat degradation and fishing are major drivers of temporal and spatial changes in fish communities. The independent effects of these drivers are well documented, but the relative importance and interaction between fishing and habitat shifts is poorly understood, particularly in complex systems such as coral reefs. To assess the combined and relative effects of fishing and habitat we examined the composition of fish communities on patch reefs across a gradient of high to low structural complexity in fished and unfished areas of the Ningaloo Marine Park, Western Australia. Biomass and species richness of fish were positively correlated with structural complexity of reefs and negatively related to macroalgal cover. Total abundance of fish was also positively related to structural complexity, however this relationship was stronger on fished reefs than those where fishing is prohibited. The interaction between habitat condition and fishing pressure is primarily due to the high abundance of small bodied planktivorous fish on fished reefs. However, the influence of management zones on the abundance and biomass of predators and target species is small, implying spatial differences in fishing pressure are low and unlikely to be driving this interaction. Our results emphasise the importance of habitat in structuring reef fish communities on coral reefs especially when gradients in fishing pressure are low. The influence of fishing effort on this relationship may however become more important as fishing pressure increases. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Fishing degrades size structure of coral reef fish communities.

    Science.gov (United States)

    Robinson, James P W; Williams, Ivor D; Edwards, Andrew M; McPherson, Jana; Yeager, Lauren; Vigliola, Laurent; Brainard, Russell E; Baum, Julia K

    2017-03-01

    Fishing pressure on coral reef ecosystems has been frequently linked to reductions of large fishes and reef fish biomass. Associated impacts on overall community structure are, however, less clear. In size-structured aquatic ecosystems, fishing impacts are commonly quantified using size spectra, which describe the distribution of individual body sizes within a community. We examined the size spectra and biomass of coral reef fish communities at 38 US-affiliated Pacific islands that ranged in human presence from near pristine to human population centers. Size spectra 'steepened' steadily with increasing human population and proximity to market due to a reduction in the relative biomass of large fishes and an increase in the dominance of small fishes. Reef fish biomass was substantially lower on inhabited islands than uninhabited ones, even at inhabited islands with the lowest levels of human presence. We found that on populated islands size spectra exponents decreased (analogous to size spectra steepening) linearly with declining biomass, whereas on uninhabited islands there was no relationship. Size spectra were steeper in regions of low sea surface temperature but were insensitive to variation in other environmental and geomorphic covariates. In contrast, reef fish biomass was highly sensitive to oceanographic conditions, being influenced by both oceanic productivity and sea surface temperature. Our results suggest that community size structure may be a more robust indicator than fish biomass to increasing human presence and that size spectra are reliable indicators of exploitation impacts across regions of different fish community compositions, environmental drivers, and fisheries types. Size-based approaches that link directly to functional properties of fish communities, and are relatively insensitive to abiotic variation across biogeographic regions, offer great potential for developing our understanding of fishing impacts in coral reef ecosystems. © 2016

  2. Essential Fish Habitat (EFH) Areas Protected From Fishing

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Designated Essential Fish Habitat (EFH) areas where fishing or the use of fishing gears has been restricted or modified in order to minimize the adverse effects of...

  3. New classical inversion formulas for centrosymmetric electric and magnetic fields; focusing potentials

    International Nuclear Information System (INIS)

    Bogdanov, I.V.; Demkov, Y.N.

    1982-01-01

    New inversion formulas are obtained for the classical scattering of a charged particle by a spherical or axisymmetric electric or magnetic field at a fixed impact parameter or angular momentum. For different cases, focusing fields are obtained similar to those previously considered for scattering by an electric field at a given energy, viz., of the backscattering (cat's eye), Maxwell fish eye, or Luneberg lens type. A magnetoelectric analogy is formulated, namely the existence of equivalent axisymmetric electric and magnetic fields that scatter charged particles in identical fashion

  4. Fishing Fish Stem Cells and Nuclear Transplants

    OpenAIRE

    Hong, Yunhan

    2011-01-01

    Fish has been the subject of various research fields, ranging from ecology, evolution, physiology and toxicology to aquaculture. In the past decades fish has attracted considerable attention for functional genomics, cancer biology and developmental genetics, in particular nuclear transfer for understanding of cytoplasmic-nuclear relationship. This special issue reports on recent progress made in fish stem cells and nuclear transfer.

  5. Do Fish Resist?

    Directory of Open Access Journals (Sweden)

    Dinesh Joseph Wadiwel

    2016-03-01

    Full Text Available There have been a number of scientific studies on the question of whether fish feel pain. Some have suggested that some fish indeed do feel pain and that this has significant welfare implications (2003. Others have argued that fish do not have the brain development necessary to feel pain. In terms of number of animals killed, the slaughter of sea animals for human consumption significantly exceeds that of any land animals that we use for food, and sea animal slaughter practices frequently lack any basic welfare protections. If fish can be shown to feel pain—or more importantly, if humans can agree that fish feel pain—then this would place a significant question mark over many contemporary fishing practices.  This article substitutes the question 'Do Fish Feel Pain?' with an alternative: 'Do Fish Resist?' It explores the conceptual problems of understanding fish resistance, and the politics of epistemology that surrounds and seeks to develop a conceptual framework for understanding fish resistance to human capture by exploring the development of fishing technologies - the hook, the net and contemporary aquaculture.

  6. Consumer evaluation of fish quality as basis for fish market segmentation

    DEFF Research Database (Denmark)

    Verbeke, Wim; Vermeir, Iris; Brunsø, Karen

    2007-01-01

    evaluation: personal relevance attached to fish quality and self-confidence in fish quality evaluation, which allow segmenting the market in four fish consumer segments. The segments are typified as Uninvolved, Uncertain, Self-confident and Connoisseurs, and have distinctive behavioural, attitudinal......This paper focuses on consumer evaluation of fish quality and its association with fish consumption, risk and benefit beliefs and information processing variables. Cross-sectional data were collected from a sample of 429 consumers in March 2003 in Belgium. Two dimensions shape fish quality...... and socio-demographic profiles. The Uninvolved are mainly young males, have the lowest fish consumption level, weakest belief in health benefits from eating fish, and lowest interest in both search and credence information cues. Uncertain fish consumers are mainly females, with a tendency of lower education...

  7. Fish Commoditization: Sustainability Strategies to Protect Living Fish

    Science.gov (United States)

    Lam, Mimi E.; Pitcher, Tony J.

    2012-01-01

    The impacts of early fishing on aquatic ecosystems were minimal, as primitive technologies were used to harvest fish primarily for food. As fishing technology grew more sophisticated and human populations dispersed and expanded, local economies transitioned from subsistence to barter and trade. Expanded trade networks and mercantilization led to…

  8. Fish silage as feed ingredient for fish and livestock

    NARCIS (Netherlands)

    Rurangwa, E.; Vuuren, van A.M.; Poelman, M.

    2014-01-01

    The present report analyses through a literature review the potential of fish silage to valorise fish processing by-products into economically relevant protein sources for fish and livestock feed production in East Africa.

  9. Northwest conservation and electric power plan 1986. Volume I

    International Nuclear Information System (INIS)

    Anon.

    1988-01-01

    This 20 year plan is prepared in accordance with the Pacific Northwest Electric Power Planning and Conservation Act - Public Law 96-501, of 1980. This Act required the Council to develop and adopt a 20-year electrical power plan for the region with a program to protect, mitigate and enhance the fish and wildlife affected by hydroelectric development in the Columbia River Basin. The plan provides a 25 year history of the regions power development and comments on its unique features and changing nature. Presentations covers problems, solutions and the planning strategy for risk management. The existing electrical power system is discussed along with future electricity needs, generating resources, conservation of resources, regional needs and resources, and the 1986 action plan. Underlying details are provided in Volume II

  10. Ultrafast traveling wave dominates the electric organ discharge of Apteronotus leptorhynchus: an inverse modelling study.

    Science.gov (United States)

    Shifman, Aaron R; Longtin, André; Lewis, John E

    2015-10-30

    Identifying and understanding the current sources that give rise to bioelectric fields is a fundamental problem in the biological sciences. It is very difficult, for example, to attribute the time-varying features of an electroencephalogram recorded from the head surface to the neural activity of specific brain areas; model systems can provide important insight into such problems. Some species of fish actively generate an oscillating (c. 1000 Hz) quasi-dipole electric field to communicate and sense their environment in the dark. A specialized electric organ comprises neuron-like cells whose collective signal underlies this electric field. As a step towards understanding the detailed biophysics of signal generation in these fish, we use an anatomically-detailed finite-element modelling approach to reverse-engineer the electric organ signal over one oscillation cycle. We find that the spatiotemporal profile of current along the electric organ constitutes a travelling wave that is well-described by two spatial Fourier components varying in time. The conduction velocity of this wave is faster than action potential conduction in any known neuronal axon (>200 m/s), suggesting that the spatiotemporal features of high-frequency electric organ discharges are not constrained by the conduction velocities of spinal neuron pathways.

  11. Introducing a open-quote modular close-quote approach to fish screen installation

    International Nuclear Information System (INIS)

    Taft, E.P.; Winchell, F.C.; Cook, T.C.; Sullivan, C.W.

    1992-01-01

    A new fish screen design-the modular inclined screen-promises to offer a versatile and cost-effective solution for fish protection in many situation. In an effort to provide the hydroelectric industry with more cost-effective alternatives to existing fish screen designs, the Electric Power Research Institute (EPRI) recently has undertaken several research projects. One focus of EPRI's research has been on the development and testing of high-velocity fish screens. This program has led to the development of a new screening concept, which shows promise for providing effective protection for a wide range of fish species at hydro plants, steam generating facilities, and irrigation diversions. The concept, known as the Modular Inclined Screen (MIS), currently is being evaluated in laboratory studies prior to field application. The screen is of open-quotes modularclose quotes design so as to provide the flexibility necessary for application at a broad range of water intakes. The module is suitable for installation in penstocks, canals, and head pond intakes. The MIS module consists of an entrance with a trashrack, dewatering stoplog slots, an inclined wedgewire screen set at a shallow angle of 10 to 20 degrees to the flow, and a bypass for diverting fish to a transport pipe. The screen is mounted on a pivot shaft so that it can be cleaned via rotation and backflushing. The module is completely enclosed, and is designed to operate at water velocities ranging from 2 to 10 feet per second depending on the fish species and life stages to be protected. Laboratory studies are under way to evaluate the design configuration that yields the best hydraulic conditions for safe fish passage, and the biological effectiveness of this design in diverting selected fish species to the bypass

  12. Fish elevator and method of elevating fish

    Science.gov (United States)

    Truebe, Jonathan; Drooker, Michael S.

    1984-01-01

    A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water.

  13. Reduced Spill at Hydropower Dams: Opportunities for More Generation and Increased Fish Population

    Energy Technology Data Exchange (ETDEWEB)

    Coutant, Charles C [ORNL; Mann, Roger [RMecon, Davis, California; Sale, Michael J [ORNL

    2006-09-01

    This report indicates that reduction of managed spill at hydropower dams can speed implementation of technologies for fish protection and achieve economic goals. Spill of water over spillways is managed in the Columbia River basin to assist downstream-migrating juvenile salmon, and is generally believed to be the most similar to natural migration, benign and effective passage route; other routes include turbines, intake screens with bypasses, and surface bypasses. However, this belief may be misguided, because spill is becoming recognized as less than natural, with deep intakes below normal migration depths, and likely causing physical damages from severe shear on spillways, high turbulence in tail waters, and collisions with baffle blocks that lead to disorientation and predation. Some spillways induce mortalities comparable to turbines. Spill is expensive in lost generation, and controversial. Fish-passage research is leading to more fish-friendly turbines, screens and bypasses that are more effective and less damaging, and surface bypasses that offer passage of more fish per unit water volume than does spill (leaving more water for generation). Analyses by independent economists demonstrated that goals of increased fish survival over the long term and net gain to the economy can be obtained by selectively reducing spill and diverting some of the income from added power generation to research, development, and installation of fish-passage technologies. Such a plan would selectively reduce spill when and where least damaging to fish, increase electricity generation using the water not spilled and use innovative financing to direct monetary gains to improving fish passage.

  14. Effect of electric barrier on passage and physical condition of juvenile and adult rainbow trout

    Science.gov (United States)

    Layhee, Megan J.; Sepulveda, Adam; Shaw, Amy; Smuckall, Matthew; Kapperman, Kevin; Reyes, Alejandro

    2016-01-01

    Electric barriers can inhibit passage and injure fish. Few data exist on electric barrier parameters that minimize these impacts and on how body size affects susceptibility, especially to nontarget fish species. The goal of this study was to determine electric barrier voltage and pulse-width settings that inhibit passage of larger bodied rainbow trout Oncorhynchus mykiss (215–410 mm fork length) while allowing passage of smaller bodied juvenile rainbow trout (52–126 mm) in a static laboratory setting. We exposed rainbow trout to 30-Hz pulsed-direct current voltage gradients (0.00–0.45 V cm−1) and pulse widths (0.0–0.7 ms) and recorded their movement, injury incidence, and mortality. No settings tested allowed all juveniles to pass while impeding all adult passage. Juvenile and adult rainbow trout avoided the barrier at higher pulse widths, and fewer rainbow trout passed the barrier at 0.7-ms pulse width compared to 0.1 ms and when the barrier was turned off. We found no effect of voltage gradient on fish passage. No mortality occurred, and we observed external bruising in 5 (7%) juvenile rainbow trout and 15 (21%) adult rainbow trout. This study may aid managers in selecting barrier settings that allow for increased juvenile passage.

  15. Fluctuations and trends in structure of fish community in Koporskaya Bay coastal waters (Gulf of Finland, Baltic Sea) and influence of water-intake facilities of the Leningrad nuclear power plant on fish fauna

    International Nuclear Information System (INIS)

    Zimin, V.L.

    1996-01-01

    The investigation is based on data obtained in 1978-1995 in Koporskaya Bay (eastern part of the Gulf of Finland), known as the cooling water-body of Leningrad (St. Petersburg) nuclear power plant Leningrad (NPP). 45 fish species were recorded in this period. The fish species diversity reduced significantly in last decade (from 8-9 in early 1980s up to 4-5 species in the nucleus of fish community in 1990s). Most vulnerable species, such as salmonids and coregonids, tend to disappear. Koporskaya Bay coastal area is now dominated by abundant three-spined and nine-spined sticklebacks. However, the relatively improved situation have occurred after beginning of reparation works at the 1st reactor unit, when the thermal loading was declined significantly. Great amount of fishes were perished at the water-intake facilities (more than 400 ton/year, in average). Changes in fish community structure caused noticeable changes in commercial fishing: the average percentage part of baltic herring (main object of fishing in the eastern Gulf of Finland) in commercial catches ranged from 90 up to 98% in the time before the LNPP started in operating, but from 1975, especially in last decade when LNPP has reached their project electrical capacity in 1981, we can see significant variations in herring's share (29-80%) in catches

  16. Laboratory Studies of the Effects of Static and Variable Magnetic Fields on Freshwater Fish

    Energy Technology Data Exchange (ETDEWEB)

    Cada, Glenn F [ORNL; Bevelhimer, Mark S [ORNL; Fortner, Allison M [ORNL; Riemer, Kristina P [ORNL; Schweizer, Peter E [ORNL

    2012-04-01

    There is considerable interest in the development of marine and hydrokinetic energy projects in rivers, estuaries, and coastal ocean waters of the United States. Hydrokinetic (HK) technologies convert the energy of moving water in river or tidal currents into electricity, without the impacts of dams and impoundments associated with conventional hydropower or the extraction and combustion of fossil fuels. The Federal Energy Regulatory Commission (FERC) maintains a database that displays the geographical distribution of proposed HK projects in inland and tidal waters (FERC 2012). As of March 2012, 77 preliminary permits had been issued to private developers to study HK projects in inland waters, the development of which would total over 8,000 MW. Most of these projects are proposed for the lower Mississippi River. In addition, the issuance of another 27 preliminary permits for HK projects in inland waters, and 3 preliminary permits for HK tidal projects (totaling over 3,100 MW) were under consideration by FERC. Although numerous HK designs are under development (see DOE 2009 for a description of the technologies and their potential environmental effects), the most commonly proposed projects entail arrays of rotating devices, much like submerged wind turbines, that are positioned in the high-velocity (high energy) river channels. The many diverse HK designs imply a diversity of environmental impacts, but a potential impact common to most is the effect on aquatic organisms of electromagnetic fields (EMF) created by the projects. The submerged electrical generator will emit an EMF into the surrounding water, as will underwater cables used to transmit electricity from the generator to the shore, between individual units in an array (inter-turbine cables), and between the array and a submerged step-up transformer. The electric current moving through these cables will induce magnetic fields in the immediate vicinity, which may affect the behavior or viability of fish and

  17. Mercury and stable isotope signatures in caged marine fish and fish feeds

    Energy Technology Data Exchange (ETDEWEB)

    Onsanit, Sarayut; Chen, Min; Ke, Caihuan [State Key Laboratory for Marine Environmental Science, College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005 (China); Wang, Wen-Xiong [State Key Laboratory for Marine Environmental Science, College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005 (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Mercury concentrations in caged fish were closely related to Hg concentrations in fish feeds. Black-Right-Pointing-Pointer The trophic transfer factor of methylmercury was dependent on fish feeds, and was the highest for fish fed on pellet feeds. Black-Right-Pointing-Pointer Fish farming may be a good way of reducing the human exposure to Hg because Hg levels can be carefully controlled. - Abstract: Total mercury (THg) and methylmercury (MeHg) concentrations were determined in four species of marine caged carnivorous fish, one species of herbivorous fish and three types of fish feeds (dried pellet feed, forage fish and fish viscera), collected from five cage sites in the rural areas along Fujian coastline, China. For the carnivorous fish, the concentrations of THg and MeHg ranged from 0.03 to 0.31 {mu}g/g and from 0.02 to 0.30 {mu}g/g on wet weight basis, respectively. The concentrations were lower for the herbivorous fish with both within the range of 0.01-0.03 {mu}g/g. Out of the three tested fish feeds, tuna viscera contained the highest level of mercury (0.20 {mu}g/g THg and 0.13 {mu}g/g MeHg), with pellet feed containing the lowest level (0.05 {mu}g/g THg and 0.01 {mu}g/g MeHg). The calculated trophic transfer factor of MeHg was the highest (12-64) for fish fed on pellet feeds, and was the lowest for fish fed on tuna viscera. A significant relationship was found between Hg concentrations in caged fish and in fish feeds, thus Hg was primarily accumulated from the diet. Furthermore, the stable isotope {delta}{sup 15}N was positively correlated with the Hg concentration in two caged sites, indicating that {delta}{sup 15}N may be a suitable tool for tracking mercury in caged fish. We conclude that fish farming may be a good way of reducing the human exposure to Hg because mercury levels can be carefully controlled in such farming systems.

  18. Mercury and stable isotope signatures in caged marine fish and fish feeds

    International Nuclear Information System (INIS)

    Onsanit, Sarayut; Chen, Min; Ke, Caihuan; Wang, Wen-Xiong

    2012-01-01

    Highlights: ► Mercury concentrations in caged fish were closely related to Hg concentrations in fish feeds. ► The trophic transfer factor of methylmercury was dependent on fish feeds, and was the highest for fish fed on pellet feeds. ► Fish farming may be a good way of reducing the human exposure to Hg because Hg levels can be carefully controlled. - Abstract: Total mercury (THg) and methylmercury (MeHg) concentrations were determined in four species of marine caged carnivorous fish, one species of herbivorous fish and three types of fish feeds (dried pellet feed, forage fish and fish viscera), collected from five cage sites in the rural areas along Fujian coastline, China. For the carnivorous fish, the concentrations of THg and MeHg ranged from 0.03 to 0.31 μg/g and from 0.02 to 0.30 μg/g on wet weight basis, respectively. The concentrations were lower for the herbivorous fish with both within the range of 0.01–0.03 μg/g. Out of the three tested fish feeds, tuna viscera contained the highest level of mercury (0.20 μg/g THg and 0.13 μg/g MeHg), with pellet feed containing the lowest level (0.05 μg/g THg and 0.01 μg/g MeHg). The calculated trophic transfer factor of MeHg was the highest (12–64) for fish fed on pellet feeds, and was the lowest for fish fed on tuna viscera. A significant relationship was found between Hg concentrations in caged fish and in fish feeds, thus Hg was primarily accumulated from the diet. Furthermore, the stable isotope δ 15 N was positively correlated with the Hg concentration in two caged sites, indicating that δ 15 N may be a suitable tool for tracking mercury in caged fish. We conclude that fish farming may be a good way of reducing the human exposure to Hg because mercury levels can be carefully controlled in such farming systems.

  19. Unintended effects of electrofishing on nongame fishes

    Science.gov (United States)

    Miranda, Leandro E.; Kidwell, R. H.

    2010-01-01

    Most studies of injury associated with electrofishing have focused on game fishes, but few have given attention to cohabiting small nongame species. Under controlled laboratory conditions, we subjected small nongame cyprinids, ictalurids, and percids to a wide range of voltages and waveforms to examine potential harmful effects. Fish were treated with power levels distributed uniformly between the thresholds required to immobilize game fish and also were subjected multiple times to those thresholds to simulate the range of conditions that might exist in a heterogeneous electrical field formed during electrofishing in field situations. Across waveforms and species, the incidence of hemorrhages averaged 2% (range = 0–20%), the incidence of spinal injuries averaged 6% (range = 0–30%), and mortality averaged 16% (range = 0–90%). Continuous DC was generally less harmful than pulsed-DC waveforms; hemorrhages and spinal injuries tended to increase with high pulse frequencies, and mortalities tended to increase with low pulse frequencies. Ambiguities in the results were apparent, suggesting that some species may experience extensive harm, whereas others may not. Given the potential to harm numerically small populations and populations of imperiled species, we suggest (1) expanded efforts to overcome the power limitations that prevent effective use of continuous-DC electrofishing in many field situations and (2) pilot studies at geographic locations where numerically small populations of nongame species may be a concern.

  20. Tendency in fishing development and fish consumption in Serbia

    Directory of Open Access Journals (Sweden)

    Tešić Milan

    2013-01-01

    Full Text Available Production and catch of fish in Serbia increases from year to year, while in the world it reached its peak at the beginning of this century. Serbia has all the favorable natural and economic conditions for further development of fishing. Out of total production, that is, annual fish catch in Serbia, the greatest part is sold by organized purchase, lower part is exported, and the reminder goes to the market through retail. It is well known that food consumption, therefore fish consumption, depends on several factors such as the production level, retail price, consumers purchasing power and their eating habits. Therefore, when analyzing the tendency of production and consumption of fish in Serbia, it is important to investigate the influence of production, price and purchasing power of consumers on it. In order to investigate the set objective, there were used corresponding quantitative data obtained by Statistical Office of the Republic of Serbia. On the basis of the original data, there were determined certain parameters, which were used as variables for calculation of correlational-regressive and maginal analysis for determining the elasticity of demand and consummation of fish per capita in Serbia. Production and catch of fish in Serbia tended to increase during the observed period, with annual growth rate of 17.4%. Beside the fact that annual growth rate is 4.8%, fish consumption per capita in Serbia is still quite small (X=4.89kg, what is a consequence of population habit to consume predominantly meat. In our study we have found out that fish consumption in Serbia mostly depend on fish production per capita (rxy=0.6364, as well as on groos (rxy=0.6045 and net (rxy=0.5969 earnings. Also, it is determined that consumption elasticity has the highest growth in regard to fish production per capita. [Projekat Ministarstva nauke Republike Srbije, br. TR 31011

  1. Fish ladders: safe fish passage or hotspot for predation?

    Directory of Open Access Journals (Sweden)

    Angelo Antonio Agostinho

    Full Text Available Fish ladders are a strategy for conserving biodiversity, as they can provide connectivity between fragmented habitats and reduce predation on shoals that accumulate immediately below dams. Although the impact of predation downstream of reservoirs has been investigated, especially in juvenile salmonids during their downstream movements, nothing is known about predation on Neotropical fish in the attraction and containment areas commonly found in translocation facilities. This study analysed predation in a fish passage system at the Lajeado Dam on the Tocantins River in Brazil. The abundance, distribution, and the permanence (time spent of large predatory fish along the ladder, the injuries imposed by piranhas during passage and the presence of other vertebrate predators were investigated. From December 2002 to October 2003, sampling was conducted in four regions (downstream, along the ladder, in the forebay, and upstream of the reservoir using gillnets, cast nets and counts or visual observations. The captured fish were tagged with thread and beads, and any mutilations were registered. Fish, birds and dolphins were the main predator groups observed, with a predominance of the first two groups. The entrance to the ladder, in the downstream region, was the area with the highest number of large predators and was the only region with relevant non-fish vertebrates. The main predatory fish species were Rhaphiodon vulpinus, Hydrolycus armatus, and Serrasalmus rhombeus. Tagged individuals were detected predating along the ladder for up to 90 days. Mutilations caused by Serrasalmus attacks were noted in 36% of species and 4% of individuals at the top of the ladder. Our results suggested that the high density of fish in the restricted ladder environment, which is associated with injuries suffered along the ladder course and the presence of multiple predator groups with different predation strategies, transformed the fish corridor into a hotspot for

  2. Occurrence of PCDD/F, PCB, PBDE, PFAS, and organotin compounds in fish meal, fish oil and fish feed.

    Science.gov (United States)

    Suominen, K; Hallikainen, A; Ruokojärvi, P; Airaksinen, R; Koponen, J; Rannikko, R; Kiviranta, H

    2011-10-01

    We analysed polychlorinated dibenzo-p-dioxins and furans (PCDD/F, dioxins), and polychlorinated biphenyls (PCB) in 13 fish meal, five fish oil, and seven fish feed samples. Polybrominated diphenyl ethers (PBDE), organotin compounds (OTC), and perfluoroalkylated substances (PFAS) were analysed in ten fish meal, two fish oil, and two fish feed samples. All measured TEQ concentrations of PCDD/F and PCB were below the maximum levels set by Directive 2002/32/EC. There was no correlation between concentrations of WHOPCDD/F-TEQ and indicator PCB in our samples. The most common congeners among PBDEs were BDE-47 and BDE-100. BDE-209 was present in five fish meals of the ten analysed. Tributyltin (TBT) was the predominant congener in all samples except in three fish meals, where monobutyltin (MBT) was the major congener. Perfluorooctane sulphonate (PFOS) was the predominant congener in six fish meals of the ten analysed. There was large variation in concentrations and congener distributions of the studied compounds between our samples. Our results underline a need to pay special attention to the origin and purity of feed raw material of marine origin. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Fish elevator and method of elevating fish

    Energy Technology Data Exchange (ETDEWEB)

    Truebe, J.; Drooker, M.S.

    1984-02-14

    A means and method are disclosed for transporting fish from a lower body of water to a higher body of water. The means comprise a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder. The movement of the fish into the discharge passage is aided by the continuous overflow of water still being pumped into the lock. A pipe may be connected to the discharge passage to deliver the fish to a selected location in the upper body of water. 6 figs.

  4. Fish under exercise

    NARCIS (Netherlands)

    Palstra, A.P.; Planas, J.V.

    2011-01-01

    Improved knowledge on the swimming physiology of fish and its application to fisheries science and aquaculture (i.e., farming a fitter fish) is currently needed in the face of global environmental changes, high fishing pressures, increased aquaculture production as well as increased concern on fish

  5. DNA metabarcoding of fish larvae for detection of non-native fishes

    Science.gov (United States)

    Our objective was to evaluate the use of fish larvae for early detection of non-native fishes, comparing traditional and molecular taxonomy approaches to investigate potential efficiencies. Fish larvae present an interesting opportunity for non-native fish early detection because...

  6. Improvement of cooking quality and gel formation capacity of Bombay duck (Harpodon nehereus) fish meat.

    Science.gov (United States)

    Rupsankar, Chakrabarti

    2010-10-01

    High moisture content (89%) along with high enzymatic and bacteriological activity in Bombay duck (Harpodon nehereus) meat are responsible for short shelf life and disintegration of meat in cooking. Minimum solubility was at pH 5 (iso-electric point) of muscle protein. Citric acid- sodium citrate buffer (pH 5) with 0.2% potassium sorbate was very effective in reducing moisture in dressed fish and in increasing shelf life up to 4 days at ambient temperature (25-28 °C). Reduction in moisture in meat improved its cooking quality and gel formation capacity with increased protein content. Fish meat contained 1.0-1.5% NaCl and produced stronger gel by using 2% NaCl than conventionally prepared gel with 4% NaCl. Washing fish mince with cold water followed by pressing at pH 5, gave fish cake with more salt soluble protein and better gel strength (>500 gcm) than the same operation done at ambient temperature.

  7. Preservation of fish and fish products by use of ionizing radiation

    International Nuclear Information System (INIS)

    Chuaqui-Offermanns, Noemi.

    1986-09-01

    This report reviews the use of the radurization process in the preservation of fish and fish products. The literature describes several aspects of the process such as the fish species and the doses required, the wholesomeness of the radurized fish, and recommendations by international authorities on the applicability of the process. Areas of further research have been identified. The report concludes that radurization is an effective process for extending the shelf life of fish and fish products. Doses ranging from 0.75 to 2.5 kGy extend the shelf life two to three times compared to unirradiated controls. The loss of nutritional value at these doses is insignificant, and no deleterious short- or long-term toxicological effects have been detected in studies on animals. However, further study is required on consumer acceptance, economic feasibility, and radiation sensitivity of parasites in fish and fish products. 159 refs

  8. "Fish Friendly" Hydropower Turbine Development and Deployment. Alden Turbine Preliminary Engineering and Model Testing

    Energy Technology Data Exchange (ETDEWEB)

    Dixon, D. [Electric Power Research Institute, Palo Alto, CA (United States)

    2011-10-01

    This report presents the results of a collaborative research project funded by the Electric Power Research Institute (EPRI), the U.S. Department of Energy (DOE), and hydropower industry partners with the objective of completing the remaining developmental engineering required for a “fish-friendly” hydropower turbine called the Alden turbine.

  9. Artisan fishing and the fishing company in Óbidos, Pará

    Directory of Open Access Journals (Sweden)

    Adriana de Aviz

    2006-08-01

    Full Text Available This work is product of the Project "The time of the plant: the disciplinamento of the workers of the fishing industry (Óbidos-Pará: a comparative study", developed in the years of 2002 and 2003 in the municipality of Óbidos, Pará, objectifying to understand the importance of the time in the disciplinamento of the work in the obidense fishing company. Interviews opened in entrepreneurs had been carried through of fish, controlling, heads of quality control, people in charge of hall and other actors involved in the sector fishing boat and applied half-open questionnaires with laborers and fishing. One used the photographic, recording register and the notebook of notations. The research was carried through in the fishing companies Mundial and Pasquarelli, Colony Z-19 Fishing, in the boats (river Amazon of the artisan fishing and in its residences. As central focus it was looked for to unmask the characteristics of the 'disciplined time' in the sector of improvement of the fishing company, and to detach the joint of the 'natural time' in the process of capture of the fished one. Leaving of these estimated, it was used the 'disciplined time' and the 'natural time' conceived by Thompson (1975.

  10. Concentration of elements in whole-body fish, fish fillets, fish muscle plugs, and fish eggs from the 2008 Missouri Department of Conservation General Contaminant Monitoring Program

    Science.gov (United States)

    May, Thomas W.; Walther, Michael J.; Brumbaugh, William G.; McKee, Michael J.

    2009-01-01

    This report presents the results of a contaminant monitoring survey conducted annually by the Missouri Department of Conservation to examine the levels of selected elemental contaminants in whole-body fish, fish fillets, fish muscle plugs, and fish eggs. Whole-body, fillet, or egg samples of catfish (Ictalurus punctatus, Ictalurus furcatus, Pylodictis olivaris), largemouth bass (Micropterus salmoides), walleye (Sander vitreus), crappie (Pomoxis annularis, Pomoxis nigromaculatus), shovelnose sturgeon (Scaphirhynchus platorynchus), northern hog sucker (Hypentelium nigricans), and Missouri saddled darter (Etheostoma tetrazonum) were collected from 23 sites as part of the Missouri Department of Conservation's Fish Contaminant Monitoring Program. Fish dorsal muscle plugs also were collected from walleye (Sander vitreus) at one of the sites.

  11. Fishing-gear restrictions and biomass gains for coral reef fishes in marine protected areas.

    Science.gov (United States)

    Campbell, Stuart J; Edgar, Graham J; Stuart-Smith, Rick D; Soler, German; Bates, Amanda E

    2018-04-01

    Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing-gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no-take, hook-and-line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no-take zones) most benefited community- and family-level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community-level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing-gear types that affect biomass of a diverse set of reef fish families. © 2017 Society for Conservation Biology.

  12. Chapter 11 - Electrical Coupling in the Generation of Vertebrate Motor Rhythms

    DEFF Research Database (Denmark)

    Li, W.C.; Rekling, Jens Christian

    2017-01-01

    Many forms of vertebrate motor activity like chewing, breathing, and locomotion are rhythmic. This requires synchronized discharges of motoneurons controlling different muscle groups in an orchestrated manner. We provide a brief review of the presence and role of electrical coupling in a few well...... of electrical coupling in vertebrate motor rhythms appears to be critically dependent on developmental age, with more crucial functions in the early postnatal period than in the adult.......-studied systems: the pacemaker nucleus in weakly electric fish; mesencephalic trigeminal nucleus involved in chewing rhythms; mammalian spinal motoneurons and excitatory interneurons in the Xenopus tadpole swimming circuit, brainstem circuits underlying breathing rhythm, and central respiratory chemosensitivity...

  13. The campaign to DNA barcode all fishes, FISH-BOL.

    Science.gov (United States)

    Ward, R D; Hanner, R; Hebert, P D N

    2009-02-01

    FISH-BOL, the Fish Barcode of Life campaign, is an international research collaboration that is assembling a standardized reference DNA sequence library for all fishes. Analysis is targeting a 648 base pair region of the mitochondrial cytochrome c oxidase I (COI) gene. More than 5000 species have already been DNA barcoded, with an average of five specimens per species, typically vouchers with authoritative identifications. The barcode sequence from any fish, fillet, fin, egg or larva can be matched against these reference sequences using BOLD; the Barcode of Life Data System (http://www.barcodinglife.org). The benefits of barcoding fishes include facilitating species identification, highlighting cases of range expansion for known species, flagging previously overlooked species and enabling identifications where traditional methods cannot be applied. Results thus far indicate that barcodes separate c. 98 and 93% of already described marine and freshwater fish species, respectively. Several specimens with divergent barcode sequences have been confirmed by integrative taxonomic analysis as new species. Past concerns in relation to the use of fish barcoding for species discrimination are discussed. These include hybridization, recent radiations, regional differentiation in barcode sequences and nuclear copies of the barcode region. However, current results indicate these issues are of little concern for the great majority of specimens.

  14. Fish parasites, fish food, and the marine environment | Nnadi ...

    African Journals Online (AJOL)

    The paper addresses the incontrovertible fact that fish and fish products have historically been a reliable supplier of protein, in particular, and food, in general for humans. Seventy to a hundred metric tons arc caught each year since the early seventies. Fish protein represents about twenty five percent of the total animal ...

  15. Fish Marketing of Ribbon Fish (Trichiurus sp. in Nusantara Fishing Port (NFPat Palabuhanratu, West Java

    Directory of Open Access Journals (Sweden)

    Nur Bambang Azis

    2018-01-01

    Full Text Available The objective of this research is to study the marketing process of ribbon fish (Trichiurus sp., including the marketing margin, marketing agencies, traders and marketing channels The research was carried out for 3 mo in Nusantara Fishing Port (NFP, Palabuhanratu, Sukabumi, West Java. A case study was used in this research. A purposive sampling method was used to collect data from 55 respondents of fish marketing, consisting of fishermen, agents, traders, and retailers, who were involved in the marketing of ribbon fish in NFP Palabuhanratu. The result of the research showed that ribbon fish production in Palabuhanratu fluctuated from year to year. There are two types of ribbon fish marketing, i.e. type one is from fishermen to retailers, and type two is indirect marketing from fisherman to consumers through intermediate traders (exporters. The greatest marketing margin was obtained from the first type, while the smallest marketing margin was obtained from type two. The form of the market was considered to be oligopsony market. Fisherman’s share is greatest in the collectors and the smallest share is on retailers. Marketing process in traders is efficient due to its lowest margin and highest fisherman’s share.

  16. 21 CFR 102.45 - Fish sticks or portions made from minced fish.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Fish sticks or portions made from minced fish. 102... for Specific Nonstandardized Foods § 102.45 Fish sticks or portions made from minced fish. (a) The common or usual name of the food product that resembles and is of the same composition as fish sticks or...

  17. The Use of Advanced Hydroelectric Turbines to Improve Water Quality and Fish Populations

    International Nuclear Information System (INIS)

    Brookshier, P.A.; Cada, G.F.; Flynn, J.V.; Rinehart, B.N.; Sale, M.J.; Sommers, G.L.

    1999-01-01

    Hydroelectric power contributes about 10 percent of the electrical energy generated in the United States, and nearly 20 percent of the worlds electrical energy. It is a renewable energy source that can contribute significantly to reduction of greenhouse gases by offsetting conventional carbon-based electricity generation. However, rather than growing in importance, hydroelectric generation has actually declined in recent years, often as a consequence of environmental concerns centering around (1) restriction of upstream and downstream fish passage by the dam, and (2) alteration of water quality and river flows by the impoundment. The Advanced Hydropower Turbine System (AHTS) Program of the U.S. Department of Energy is developing turbine technology which would help to maximize global hydropower resources while minimizing adverse environmental effects. Major technical goals for the Program are (1) the reduction of mortality among turbine-passed fish to 2 percent or less, compared to current levels ranging up to 30 percent or greater; and (2) development of aerating turbines that would ensure that water discharged from reservoirs has a dissolved oxygen concentration of at least 6 mg/L. These advanced, environmentally friendly turbines would be suitable both for new hydropower installations and for retrofitting at existing dams. Several new turbine designs that have been developed in the initial phases of the AHTS program are described

  18. Fish Karyome: A karyological information network database of Indian Fishes.

    Science.gov (United States)

    Nagpure, Naresh Sahebrao; Pathak, Ajey Kumar; Pati, Rameshwar; Singh, Shri Prakash; Singh, Mahender; Sarkar, Uttam Kumar; Kushwaha, Basdeo; Kumar, Ravindra

    2012-01-01

    'Fish Karyome', a database on karyological information of Indian fishes have been developed that serves as central source for karyotype data about Indian fishes compiled from the published literature. Fish Karyome has been intended to serve as a liaison tool for the researchers and contains karyological information about 171 out of 2438 finfish species reported in India and is publically available via World Wide Web. The database provides information on chromosome number, morphology, sex chromosomes, karyotype formula and cytogenetic markers etc. Additionally, it also provides the phenotypic information that includes species name, its classification, and locality of sample collection, common name, local name, sex, geographical distribution, and IUCN Red list status. Besides, fish and karyotype images, references for 171 finfish species have been included in the database. Fish Karyome has been developed using SQL Server 2008, a relational database management system, Microsoft's ASP.NET-2008 and Macromedia's FLASH Technology under Windows 7 operating environment. The system also enables users to input new information and images into the database, search and view the information and images of interest using various search options. Fish Karyome has wide range of applications in species characterization and identification, sex determination, chromosomal mapping, karyo-evolution and systematics of fishes.

  19. 50 CFR 14.23 - Live farm-raised fish and farm-raised fish eggs.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 1 2010-10-01 2010-10-01 false Live farm-raised fish and farm-raised fish eggs. 14.23 Section 14.23 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF... Exportation at Designated Ports § 14.23 Live farm-raised fish and farm-raised fish eggs. Live farm-raised fish...

  20. Three Kinds of Fish

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2012-01-01

    There are three kinds of fish. Fish you were given, fish you bought and fish you lease. This might sound a bit odd, but it is nevertheless the basis for the activities of Danish commercial fishers since the introduction of transferable fishing concessions (TFCs) in 2007. In the current 2012 reform...... of market based systems are wild speculation, concentration and monopolization of fishing access and subsequent leasing with fishing communities and new entrants very likely being worse off (see for example the chapter “From fishing rights to financial derivatives” is this volume or Olson 2011; Sumaila 2010...... will examine five Danish fishing operations and discuss how they have reacted in different ways to the newly introduced system of transferable fishing concessions. By introducing TFCs as a solution to fleet overcapacity, the EU Commission will also be introducing a system where buying, selling and leasing...

  1. Fishing Access Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish & Wildlife Department maintains developed fishing access areas. These sites provide public access to waters in Vermont for shore fishing...

  2. Fish consumption behavior and fish farming attitude in Kingdom of Saudi Arabia (KSA

    Directory of Open Access Journals (Sweden)

    Abdul Qader Khan

    2018-04-01

    Full Text Available This study aimed to explore fish consumption behavior and fish farming attitude of the Saudi households in the Kingdom of Saudi Arabia (KSA. The survey was conducted in Sharurah town situated in Najran province. The data were collected through a well-structured questionnaire from 100 respondents residing in the province. Pearson Correlation Coefficient was used to see the significant and non-significant impact of the two variables. The results showed that majority (37% of the respondents fell in the age group of 25–34 and majority (35% of the respondents have high level of education i.e. up to university level. The results also depicted that majority (31% of the people consume fish and were aware of the nutritional value of fish. However, majority (85% of the respondents were not satisfied by the fish price. The results further indicated that none of the respondent was engaged in fish farming activity i.e. they had no fish farms at their homes. Furthermore, majority (83% respondents had no intentions to start fish farming at their homes in future. The study concludes that fish consumption and preference is high in the study area and people prefer fish more than chicken and meat for consumption purposes because of their knowledge regarding the nutritional value of fish. However, the age and educational level have negative impact on the respondent’s opinion about fish price in the study area. The study recommends that proper policies should be formulated to educate people about fish farming (aquaponics and its importance through fisheries extension services to enhance the interest of people in fish farming. Keywords: Fish consumption, Fish farming, Attitude, Intentions, Saudi Arabia, Aquaponics

  3. From Fishing to Fish Processing: Separation of Fish from Crustaceans in the Norway Lobster-Directed Multispecies Trawl Fishery Improves Seafood Quality.

    Directory of Open Access Journals (Sweden)

    Junita D Karlsen

    Full Text Available Fishing gears have negative impacts on seafood quality, especially on fish in the mixed trawl fishery targeting Norway lobster (Nephrops norvegicus. In this fishery, which is worth about €80 millions in Denmark alone, the quality of fish can be significantly improved by simple gear changes. A trawl codend divided into an upper and lower codend was designed to separate fish from Norway lobster during the fishing process by encourage fish to swim into the upper codend by using a frame at the entrance of the lower codend. Separate codends for fish and Norway lobster in the same gear provide the opportunity to selectively reduce small low-value fish, which will reduce catch weight and sorting time onboard the vessel. For this horizontally divided test codend and a standard codend, in which the catch was mixed, quality assessments were performed on the same batches of fish during three steps of the value chain: i aboard the fishing vessel; ii at the Fishermen's Collection Central, and iii in the production plant. Four species of fish and fillets from fish caught in the upper codend of the test codend were of significantly better quality for several of the assessed parameters compared with those caught in the standard codend: i newly caught fish showed significantly less scale loss and discolourations and had significantly better texture; ii landed fish had significantly better skin appearance and texture and significantly fewer discolourations; and iii fillets showed significantly fewer blood spots and had significantly better texture. There were no differences in injuries for newly caught fish or gaping and bruises for fillets between the test and standard codends. The decrease in catch-related damages in the test codend is explained by little contact between fish and animals with hard or spiny surfaces due to successful separation of fish and Norway lobster into the upper and lower codends, respectively, and by lower catch weight in the upper

  4. Fish tapeworm infection

    Science.gov (United States)

    Fish tapeworm infection is an intestinal infection with a parasite found in fish. ... The fish tapeworm ( Diphyllobothrium latum ) is the largest parasite that infects humans. Humans become infected when they eat raw ...

  5. Fish allergy: in review.

    Science.gov (United States)

    Sharp, Michael F; Lopata, Andreas L

    2014-06-01

    Globally, the rising consumption of fish and its derivatives, due to its nutritional value and divergence of international cuisines, has led to an increase in reports of adverse reactions to fish. Reactions to fish are not only mediated by the immune system causing allergies, but are often caused by various toxins and parasites including ciguatera and Anisakis. Allergic reactions to fish can be serious and life threatening and children usually do not outgrow this type of food allergy. The route of exposure is not only restricted to ingestion but include manual handling and inhalation of cooking vapors in the domestic and occupational environment. Prevalence rates of self-reported fish allergy range from 0.2 to 2.29 % in the general population, but can reach up to 8 % among fish processing workers. Fish allergy seems to vary with geographical eating habits, type of fish processing, and fish species exposure. The major fish allergen characterized is parvalbumin in addition to several less well-known allergens. This contemporary review discusses interesting and new findings in the area of fish allergy including demographics, novel allergens identified, immunological mechanisms of sensitization, and innovative approaches in diagnosing and managing this life-long disease.

  6. Meet the surrogate fish

    International Nuclear Information System (INIS)

    Johnson, Bob; Neitzel, Duane; Moxon, Suzanne

    1999-01-01

    This article gives details of the US Department of Energy's innovative research into the development of a sensor system that will work as a surrogate fish to provide information to aid the design of fish-friendly turbines for hydroelectric power plants. The selection of the dams for the testing of sensor fish, the release and recovery of the sensor fish, the recording of the physical forces exerted on fish as they pass through the turbines, and use of the information gathered to build more sensor fish are discussed. Fish investigations conducted at the Pacific Northwest National Laboratory are briefly described. (UK)

  7. Molecular evolution of ependymin and the phylogenetic resolution of early divergences among euteleost fishes.

    Science.gov (United States)

    Ortí, G; Meyer, A

    1996-04-01

    The rate and pattern of DNA evolution of ependymin, a single-copy gene coding for a highly expressed glycoprotein in the brain matrix of teleost fishes, is characterized and its phylogenetic utility for fish systematics is assessed. DNA sequences were determined from catfish, electric fish, and characiforms and compared with published ependymin sequences from cyprinids, salmon, pike, and herring. Among these groups, ependymin amino acid sequences were highly divergent (up to 60% sequence difference), but had surprisingly similar hydropathy profiles and invariant glycosylation sites, suggesting that functional properties of the proteins are conserved. Comparison of base composition at third codon positions and introns revealed AT-rich introns and GC-rich third codon positions, suggesting that the biased codon usage observed might not be due to mutational bias. Phylogenetic information content of third codon positions was surprisingly high and sufficient to recover the most basal nodes of the tree, in spite of the observation that pairwise distances (at third codon positions) were well above the presumed saturation level. This finding can be explained by the high proportion of phylogenetically informative nonsynonymous changes at third codon positions among these highly divergent proteins. Ependymin DNA sequences have established the first molecular evidence for the monophyly of a group containing salmonids and esociforms. In addition, ependymin suggests a sister group relationship of electric fish (Gymnotiformes) and Characiformes, constituting a significant departure from currently accepted classifications. However, relationships among characiform lineages were not completely resolved by ependymin sequences in spite of seemingly appropriate levels of variation among taxa and considerably low levels of homoplasy in the data (consistency index = 0.7). If the diversification of Characiformes took place in an "explosive" manner, over a relatively short period of time

  8. Economic differential of integrated fish, rice cum piggery and fish ...

    African Journals Online (AJOL)

    Fish, rice cum piggery and fish, rice cum poultry production integration platforms were set up to perfect the ideas of integrated fish farming in Sierra Leone. Water quality parameters measured biweekly included: dissolved oxygen, water temperature, pH, water hardness, water alkalinity, ammonia, nitrate, BOD and nitrite.

  9. Effects of fire on fish populations: Landscape perspectives on persistance of native fishes and nonnative fish invasions

    Science.gov (United States)

    Dunham, J.B.; Young, M.; Gresswell, Robert E.; Rieman, B.

    2003-01-01

    Our limited understanding of the short and long-term effects of fire on fish contributes to considerable uncertainty in assessments of the risks and benefits of fire management alternatives. A primary concern among the many potential effects of fire is the effects of fire and fire management on persistence of native fish populations. Limited evidence suggests vulnerability of fish to fire is contingent upon the quality of affected habitats, the amount and distribution of habitat (habitat fragmentation), and habitat specificity of the species in question. Species with narrow habitat requirements in highly degraded and fragmented systems are likely to be most vulnerable to fire and fire-related disturbance. In addition to effects of fire on native fish, there are growing concerns about the effects of fire on nonnative fish invasions. The role of fire in facilitating invasions by nonnative fishes is unknown, but experience with other species suggests some forms of disturbance associated with fire may facilitate invasion. Management efforts to promote persistence of fishes in fire-prone landscapes can take the form of four basic alternatives: (1) pre-fire management; (2) post-fire management; (3) managing fire itself (e.g. fire fighting); and (4) monitoring and adaptive management. Among these alternatives, pre-fire management is likely to be most effective. Effective pre-fire management activities will address factors that may render fish populations more vulnerable to the effects of fire (e.g. habitat degradation, fragmentation, and nonnative species). Post-fire management is also potentially important, but suffers from being a reactive approach that may not address threats in time to avert them. Managing fire itself can be important in some contexts, but negative consequences for fish populations are possible (e.g. toxicity of fire fighting chemicals to fish). Monitoring and adaptive management can provide important new information for evaluating alternatives, but

  10. Fish assemblages

    Science.gov (United States)

    McGarvey, Daniel J.; Falke, Jeffrey A.; Li, Hiram W.; Li, Judith; Hauer, F. Richard; Lamberti, G.A.

    2017-01-01

    Methods to sample fishes in stream ecosystems and to analyze the raw data, focusing primarily on assemblage-level (all fish species combined) analyses, are presented in this chapter. We begin with guidance on sample site selection, permitting for fish collection, and information-gathering steps to be completed prior to conducting fieldwork. Basic sampling methods (visual surveying, electrofishing, and seining) are presented with specific instructions for estimating population sizes via visual, capture-recapture, and depletion surveys, in addition to new guidance on environmental DNA (eDNA) methods. Steps to process fish specimens in the field including the use of anesthesia and preservation of whole specimens or tissue samples (for genetic or stable isotope analysis) are also presented. Data analysis methods include characterization of size-structure within populations, estimation of species richness and diversity, and application of fish functional traits. We conclude with three advanced topics in assemblage-level analysis: multidimensional scaling (MDS), ecological networks, and loop analysis.

  11. Alexander von Humboldt: galvanism, animal electricity, and self-experimentation part 1: formative years, naturphilosophie, and galvanism.

    Science.gov (United States)

    Finger, Stanley; Piccolino, Marco; Stahnisch, Frank W

    2013-01-01

    During the 1790s, Alexander von Humboldt (1769-1859), who showed an early interest in many facets of natural philosophy and natural history, delved into the controversial subject of galvanism and animal electricity, hoping to shed light on the basic nature of the nerve force. He was motivated by his broad worldview, the experiments of Luigi Galvani, who favored animal electricity in more than a few specialized fishes, and the thinking of Alessandro Volta, who accepted specialized fish electricity but was not willing to generalize to other animals, thinking Galvani's frog experiments flawed by his use of metals. Differing from many German Naturphilosophen, who shunned "violent" experiments, the newest instruments, and detailed measurement, Humboldt conducted thousands of galvanic experiments on animals and animal parts, as well as many on his own body, some of which caused him great pain. He interpreted his results as supporting some but not all of the claims made by both Galvani and Volta. Notably, because of certain negative findings and phenomenological differences, he remained skeptical about the intrinsic animal force being qualitatively identical to true electricity. Hence, he referred to a "galvanic force," not animal electricity, in his letters and publications, a theoretical position he would abandon with Volta's help early in the new century.

  12. Fish Marketing of Ribbon Fish (Trichiurus sp.) in Nusantara Fishing Port (NFP)at Palabuhanratu, West Java

    Science.gov (United States)

    Bambang, Azis Nur

    2018-02-01

    The objective of this research is to study the marketing process of ribbon fish (Trichiurus sp.), including the marketing margin, marketing agencies, traders and marketing channels The research was carried out for 3 mo in Nusantara Fishing Port (NFP), Palabuhanratu, Sukabumi, West Java. A case study was used in this research. A purposive sampling method was used to collect data from 55 respondents of fish marketing, consisting of fishermen, agents, traders, and retailers, who were involved in the marketing of ribbon fish in NFP Palabuhanratu. The result of the research showed that ribbon fish production in Palabuhanratu fluctuated from year to year. There are two types of ribbon fish marketing, i.e. type one is from fishermen to retailers, and type two is indirect marketing from fisherman to consumers through intermediate traders (exporters). The greatest marketing margin was obtained from the first type, while the smallest marketing margin was obtained from type two. The form of the market was considered to be oligopsony market. Fisherman's share is greatest in the collectors and the smallest share is on retailers. Marketing process in traders is efficient due to its lowest margin and highest fisherman's share.

  13. Changes in the North Sea fish community: evidence of indirect effects of fishing?

    DEFF Research Database (Denmark)

    Daan, N.; Gislason, Henrik; Pope, J.

    2005-01-01

    , but such changes may simply reflect the cumulative, direct effects of fishing through selective removal of large individuals. If there is resilience in a fish community towards fishing, we may expect increases in specific components, for instance as a consequence of an associated reduction in predation and....... Taking average fishing mortality of assessed commercial species as an index of exploitation rate of the fish community, it appears that fishing effort reached its maximum in the mid-1980s and has declined slightly since. If the observed changes in the community are caused by indirect effects of fishing...

  14. New salty waffle products "Fish Krekis" with fish & plant semifinished products

    Directory of Open Access Journals (Sweden)

    Fedorova Dina

    2016-04-01

    Full Text Available The study examines the directions of expansion of the range of wafer snack products of high nutritional value by using fish & plant semifinished products. The study scientifically grounds the benefits of using the new fish & plant semifinished products in manufacturing waffle salty snack products. The data provided in the article prove that the use of the fish & plant semifinished products & herbal ingredients enable a range of the new wafer snack products «Fish krekis» with high content of proteins, organic calcium, fiber and vitamins, with improved consumer properties, as well as more efficient use of Ukrainian raw fish materials.

  15. Vaccination in Fish

    DEFF Research Database (Denmark)

    Chettri, Jiwan Kumar

    vaccines have reduced the need for usage of antibiotics with more than 99 % since the 1980s. Fish can be vaccinated by three different administration routes: injection, immersion and oral vaccination. Injection vaccination (intraperitoneal injection of vaccine) is the most time consuming and labor...... intensive method, which however, provides the best protection of the fish. Immersion vaccination is used for immunization of a high number of small fish is cost-efficient and fast (30 sec immersion into vaccine). Oral vaccination (vaccine in feed) is the least efficient. As in higher vertebrates fish...... respond to vaccination by increasing the specific antibody titer and by activating the cellular responses. My talk will cover vaccination methods in fish, immune responses and some adverse effect of oil-adjuvanted vaccines in fish with reference to our work in rainbow trout, Oncorhynchus mykiss....

  16. Fish mercury levels in lakes - adjusting for Hg and fish-size covariation

    International Nuclear Information System (INIS)

    Sonesten, Lars

    2003-01-01

    Fish-size covariation can be circumvented by regression intercepts of Hg vs. fish length as lake-specific Hg levels. - Accurate estimates of lake-specific mercury levels are vital in assessing the environmental impact on the mercury content in fish. The intercepts of lake-specific regressions of Hg concentration in fish vs. fish length provide accurate estimates when there is a prominent Hg and fish-size covariation. Commonly used regression methods, such as analysis of covariance (ANCOVA) and various standardization techniques are less suitable, since they do not completely remove the fish-size covariation when regression slopes are not parallel. Partial least squares (PLS) regression analysis reveals that catchment area and water chemistry have the strongest influence on the Hg level in fish in circumneutral lakes. PLS is a multivariate projection method that allows biased linear regression analysis of multicollinear data. The method is applicable to statistical and visual exploration of large data sets, even if there are more variables than observations. Environmental descriptors have no significant impact on the slopes of linear regressions of the Hg concentration in perch (Perca fluviatilis L.) vs. fish length, suggesting that the slopes mainly reflect ontogenetic dietary shifts during the perch life span

  17. From fishing to fish processing: Separation of fish from crustaceans in the Norway lobster-directed multispecies trawl fishery improves seafood quality

    DEFF Research Database (Denmark)

    Karlsen, Junita Diana; Krag, Ludvig Ahm; Albertsen, Christoffer Moesgaard

    2015-01-01

    Fishing gears have negative impacts on seafood quality, especially on fish in the mixed trawl fishery targeting Norway lobster (Nephrops norvegicus). In this fishery, which is worth about €80 millions in Denmark alone, the quality of fish can be significantly improved by simple gear changes....... A trawl codend divided into an upper and lower codend was designed to separate fish from Norway lobster during the fishing process by encourage fish to swim into the upper codend by using a frame at the entrance of the lower codend. Separate codends for fish and Norway lobster in the same gear provide...... with hard or spiny surfaces due to successful separation of fish and Norway lobster into the upper and lower codends, respectively, and by lower catch weight in the upper codend of the test codend compared with the standard codend. The decrease in damages may also improve quality indirectly by inflicting...

  18. Using Smart Packaging in Fish and Fish Based Product

    Directory of Open Access Journals (Sweden)

    Elif Tuğçe AKSUN

    2016-11-01

    Full Text Available Food packaging have three main roles during protection, preservation and storage are still involved better continuance of food quality. Evolution of civilization and improvement of new kind of food stuffs, packaging industry must created new possibilities for preventation of food quality during shelf-life. The quality and safety of perishable food is related to microbial quality has got a significance role. Fish is a very perishable food product. It is a very low acidic food and thus is very liable to the expansion of food poisoning bacteria. Also decomposition of fish can be by reason of enzymatic spoilage, oxidation and/or bacterial spoilage. Fish is an important resource of polyunsaturated fatty acids stated to have defensive effects in opposition to heartconnected diseases. Some smart packaging mechanisms liable to determine this break down incident thought storage. In this review, smart packaging technologies that could be used to detect breakdown compounds from packed fish and fish products.

  19. In vitro evaluation of crosslinked electrospun fish gelatin scaffolds

    International Nuclear Information System (INIS)

    Gomes, S.R.; Rodrigues, G.; Martins, G.G.; Henriques, C.M.R.; Silva, J.C.

    2013-01-01

    Gelatin from cold water fish skin was electrospun, crosslinked and investigated as a substrate for the adhesion and proliferation of cells. Gelatin was first dissolved in either water or concentrated acetic acid and both solutions were successfully electrospun. Cross-linking was achieved via three different routes: glutaraldehyde vapor, genipin and dehydrothermal treatment. Solution's properties (surface tension, electrical conductivity and viscosity) and scaffold's properties (chemical bonds, weight loss and fiber diameters) were measured. Cellular viability was analyzed culturing 3T3 fibroblasts plated on the scaffolds and grown up to 7 days. The cells were fixed and observed with SEM or stained for DNA and F-actin and observed with confocal microscopy. In all scaffolds, the cells attached and spread with varying degrees. The evaluation of cell viability showed proliferation of cells until confluence in scaffolds crosslinked by glutaraldehyde and genipin; however the rate of growth in genipin crosslinked scaffolds was slow, recovering only by day five. The results using the dehydrothermal treatment were the less satisfactory. Our results show that glutaraldehyde treated fish gelatin is the most suitable substrate, of the three studied, for fibroblast adhesion and proliferation. - Highlights: ► Electrospinning of fish gelatin dissolved in both water or concentrated acetic acid ► Glutaraldehyde, genipin and dehydrothermal treatment effectively crosslink the fish gelatin fibers ► Fibroblasts effectively adhere to and propagate on all scaffolds ► Cell population is highest for glutaraldehyde crosslinked scaffolds ► Cells exhibit more filopodia and stress fibers on glutaraldehyde crosslinked scaffolds

  20. In vitro evaluation of crosslinked electrospun fish gelatin scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, S.R. [Centro de Física e Investigação Tecnológica / Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Rodrigues, G.; Martins, G.G. [Centro de Biologia Ambiental / Departamento de Biologia Animal, Faculdade de Ciências da Universidade de Lisboa, FCUL, 1749-016 Campo Grande, Lisboa (Portugal); Henriques, C.M.R. [Centro de Física e Investigação Tecnológica / Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Silva, J.C., E-mail: jcs@fct.unl.pt [Centro de Física e Investigação Tecnológica / Departamento de Física, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2013-04-01

    Gelatin from cold water fish skin was electrospun, crosslinked and investigated as a substrate for the adhesion and proliferation of cells. Gelatin was first dissolved in either water or concentrated acetic acid and both solutions were successfully electrospun. Cross-linking was achieved via three different routes: glutaraldehyde vapor, genipin and dehydrothermal treatment. Solution's properties (surface tension, electrical conductivity and viscosity) and scaffold's properties (chemical bonds, weight loss and fiber diameters) were measured. Cellular viability was analyzed culturing 3T3 fibroblasts plated on the scaffolds and grown up to 7 days. The cells were fixed and observed with SEM or stained for DNA and F-actin and observed with confocal microscopy. In all scaffolds, the cells attached and spread with varying degrees. The evaluation of cell viability showed proliferation of cells until confluence in scaffolds crosslinked by glutaraldehyde and genipin; however the rate of growth in genipin crosslinked scaffolds was slow, recovering only by day five. The results using the dehydrothermal treatment were the less satisfactory. Our results show that glutaraldehyde treated fish gelatin is the most suitable substrate, of the three studied, for fibroblast adhesion and proliferation. - Highlights: ► Electrospinning of fish gelatin dissolved in both water or concentrated acetic acid ► Glutaraldehyde, genipin and dehydrothermal treatment effectively crosslink the fish gelatin fibers ► Fibroblasts effectively adhere to and propagate on all scaffolds ► Cell population is highest for glutaraldehyde crosslinked scaffolds ► Cells exhibit more filopodia and stress fibers on glutaraldehyde crosslinked scaffolds.

  1. Retardation Of Lipid Oxidation In Fish Oil-Enriched Fish Pâté- Combination Effects

    DEFF Research Database (Denmark)

    Nielsen, Nina Skall; Jacobsen, Charlotte

    2013-01-01

    The oxidative stability during storage of fish pâté made from cod and enriched with 5% oil was investigated. Pâtés were produced with neat fish oil, pre-emulsified fish oil, microencapsulated fish oil, inert medium chain triacylglycerol (MCT) oil or a fish/rapeseed oil mixture. Addition of fish...... stored at 2 or 10C were equally stable. Mixing fish oil with rapeseed oil before emulsification slightly increased the stability of the fish pâtés. Addition of antimicrobial agents, sodium benzoate and potassium sorbate increased oxidative stability. It is recommended to produce enriched fish pâté...... by adding pre-emulsified fish oil or microencapsulated fish oil and store at preferentially 2-10C. Practical Applications: The results from this study can directly be transferred to practical applications in the food industry. Thus, the study showed that fish oil-enriched fish pâté with an acceptable...

  2. [Effects of fish on field resource utilization and rice growth in rice-fish coculture].

    Science.gov (United States)

    Zhang, Jian; Hu, Liang Liang; Ren, Wei Zheng; Guo, Liang; Wu, Min Fang; Tang, Jian Jun; Chen, Xin

    2017-01-01

    Rice field can provide habitat for fish and other aquatic animals. Rice-fish coculture can increase rice yield and simultaneously reduce the use of chemicals through reducing rice pest occurrence and nutrient complementary use. However, how fish uses food sources (e.g. phytoplankton, weeds, duckweed, macro-algal and snail) from rice field, and whether the nutrients releasing from those food sources due to fish transforming can improve rice growth are still unknown. Here, we conducted two field experiments to address these questions. One was to investigate the pattern of fish activity in the field using the method of video recording. The other was to examine the utilization of field resources by fish using stable isotope technology. Rice growth and rice yield were also exa-mined. Results showed that fish tended to be more active and significantly expanded the activity range in the rice-fish coculture compared to fish monoculture (fish not living together with rice plants). The contributions of 3 potential aquatic organisms (duckweed, phytoplankton and snail) to fish dietary were 22.7%, 34.8% and 30.0% respectively under rice-fish coculture without feed. Under the treatment with feed, however, the contributions of these 3 aquatic organisms to the fish die-tary were 8.9%, 5.9% and 1.6% respectively. The feed contribution was 71.0%. Rice-fish coculture significantly increased the nitrogen concentration in rice leaves, prolonged tillering stage by 10-12 days and increased rice spike rate and yield. The results suggested that raising fish in paddy field may transform the nutrients contained in field resources to bioavailable for rice plants through fish feeding activity, which can improve rice growth and rice yield.

  3. Advanced, Environmentally Friendly Hydroelectric Turbines for the Restoration of Fish and Water Quality

    International Nuclear Information System (INIS)

    Brookshier, P.A.; Cada, G.F.; Flynn, J.V.; Rinehart, B.N.; Sale, M.J.; Sommers, G.L.

    1999-01-01

    Hydroelectric power contributes about 10 percent of the electrical energy generated in the United States, and nearly 20 percent of the worlds electrical energy. The contribution of hydroelectric generation has declined in recent years, often as a consequence of environmental concerns centering around (1) restriction of upstream and downstream fish passage by the dam, and (2) alteration of water quality and river flows by the impoundment. The Advanced Hydropower Turbine System (AHTS) Program of the U.S. Department of Energy is developing turbine technology which would help to maximize global hydropower resources while minimizing adverse environmental effects. Major technical goals for the Program are (1) the reduction of mortality among turbine-passed fish to 2 percent or less, compared to current levels ranging up to 30 percent or greater; and (2) development of aerating turbines that would ensure that water discharged from reservoirs has a dissolved oxygen concentration of at least 6 mg/L. These advanced, environmentally friendly turbines would be suitable both for new hydropower installations and for retrofitting at existing dams. Several new turbine designs that have been he AHTS program are described

  4. Can north american fish passage tools work for South american migratory fishes?

    Directory of Open Access Journals (Sweden)

    Claudio Rafael Mariano Baigún

    Full Text Available In North America, the Numerical Fish Surrogate (NFS is used to design fish bypass systems for emigrating juvenile salmon as they migrate from hatchery outfalls and rearing habitats to adult habitat in the oceans. The NFS is constructed of three linked modules: 1 a computational fluid dynamics model describes the complex flow fields upstream of dams at a scale sufficiently resolved to analyze, understand and forecast fish movement, 2 a particle tracking model interpolates hydraulic information from the fixed nodes of the computational fluid model mesh to multiple locations relevant to migrating fish, and 3 a behavior model simulates the cognition and behavior of individual fish in response to the fluid dynamics predicted by the computational fluid dynamics model. These three modules together create a virtual reality where virtual fish exhibit realistic dam approach behaviors and can be counted at dam exits in ways similar to the real world. Once calibrated and validated with measured fish movement and passage data, the NFS can accurately predict fish passage proportions with sufficient precision to allow engineers to select one optimum alternative from among many competing structural or operational bypass alternatives. Although South American fish species are different from North American species, it is likely that the basic computational architecture and numerical methods of the NFS can be used for fish conservation in South America. Consequently, the extensive investment made in the creation of the NFS need not be duplicated in South America. However, its use in South America will require that the behavioral response of the continent's unique fishes to hydrodynamic cues must be described, codified and tested before the NFS can be used to conserve fishes by helping design efficient South American bypass systems. To this end, we identify studies that could be used to describe the movement behavior of South American fishes of sufficient detail

  5. Fish eye optics

    Science.gov (United States)

    Hudec, R.; Michalova, S.

    2017-07-01

    We report on small student (high—school) project of the Czech Academy of Sciences dealing with animal (fish) eyes and possible application in science and technology. Albeit most fishes have refractive eyes, the recent discoveries confirm that some fishes have reflective eyes with strange arrangements as well.

  6. Anadromous fish behaviour important for fish passage

    International Nuclear Information System (INIS)

    Kynard, B.E.

    1993-01-01

    An understanding of the behavior of target fish species is necessary for proper design, location, and operation of a successful upstream or downstream fishway for anadromous migrants. Important fish behaviors are seasonal and daily timing of migration; rheotaxis and near field behavior; stimulus-response behavior; swimming capability; shoaling behavior; response to physical environmental factors such as illumination, sound, water depth, current velocity, and structure; response to chemicals; and response to biological factors such as competition for space and response to predators. The information on migrant fish behavior is reviewed, using examples from the literature on the behavior of eastern anadromous species, particularly Atlantic salmon (Salmo salar) and American shad (Alosa sapidissima). 87 refs

  7. Distribution of fish species for the generic Appropriate Assessment for the construction of offshore wind farms.

    NARCIS (Netherlands)

    Hofstede, ter R.; Winter, H.V.; Os, O.G.

    2008-01-01

    The Dutch government aims at the production of 450 MW of electricity by offshore wind farms by 2010 and 6000 MW by 2020. Possibly the construction, exploitation and dismantlement of the wind farms will influence fish in the North Sea, which are protected under the European Habitat Directive or are

  8. Recombinant fish parvalbumins: Candidates for diagnosis and treatment of fish allergy.

    Science.gov (United States)

    Swoboda, Ines; Bugajska-Schretter, A; Valenta, R; Spitzauer, S

    2002-01-01

    Fish and fish products represent one of the most important causes of IgE-mediated food hypersensitivity. In sensitized individuals contact with and consumption of fish can lead to severe health problems, ranging from urticaria and dermatitis to angiedema, diarrhoea, asthma and, at worst, systemic anaphylactic reactions and death. Parvalbumin, a small calcium-binding protein present in the muscles of vertebrates, was identified as the major fish allergen. We describe the isolation and characterization of cDNA clones coding for carp parvalbumin by IgE immunoscreening of a carp muscle expression library. These clones will be the basis for the production of recombinant carp parvalbumin, a useful tool for in vitro and in vivo diagnosis of fish allergy.

  9. Selectivity of fish ladders: a bottleneck in Neotropical fish movement

    Directory of Open Access Journals (Sweden)

    Carlos Sérgio Agostinho

    Full Text Available Although dozens of fish ladders have been constructed at dams of Brazilian reservoirs, there are few studies evaluating their efficiency as a tool for the conservation of Neotropical ichthyofauna, especially for migratory species. Therefore, the present study evaluated the selectivity of the species that entered and ascended the fish ladder located next to Lajeado Dam (Luis Eduardo Magalhães Hydroelectric Power Plant on the Tocantins River. Samples were taken monthly from November, 2002 through October, 2003, in the resting pools of the ladder, using cast nets, and in the downstream stretch, using gillnets. The selectivity of the ladder in attracting fish was evaluated by comparing the occurrence, relative abundance, dominance and the congruence of abundance ranks of migratory and non-migratory species in the ladder and in the stretch of river immediately downstream. Species richness and fish abundance in the resting pools were used to evaluate selectivity along the ladder. The effects on selectivity by temporal variations in water level downriver and maximum flow velocity in the fish ladder were also analyzed. Out of the 130 species recorded downriver, 62.3% were caught in the ladder, and migratory species were clearly favored. However, more than 2/3 of the catch belonged to only three species (Rhaphiodon vulpinus, Psectrogaster amazonica and Oxydoras niger. Although the majority of the species that entered the ladder were able to reach its top, there was a sharp reduction in abundance of individuals towards the top. Temporal variations in the water level below the dam influenced richness and abundance of fish concentrated downstream and in the ladder, with lower values during periods of low water. In the ladder, a maximum flow velocity of 2.3 m/s, although also selective, proved to be more appropriate for fish ascension than a velocity of 2.8 m/s. It was concluded that the entry and ascension of the fish in the ladder were not congruent with

  10. Genotype-environment interaction in passive avoidance learning of the paradise fish (Macropodus opercularis).

    Science.gov (United States)

    Csányi, V; Gervai, J

    1985-01-01

    Passive dark avoidance conditioning and effects of the presence and absence of a fish-like dummy on the training process were studied in four inbred strains of paradise fish. Strain differences were found in the shuttle activity during habituation trials, and in the sensitivity to the mild electric shock punishment. The presence or absence of the dummy in the punished dark side of the shuttle box had a genotype-dependent effect on the measures taken during the conditioning process. The statistical analysis of the learning curves revealed differences in the way the strains varied in the different environments, i.e. genotype--environment interaction components of variances were identified. The results are discussed in the light of previous investigations and their implication in further genetic analysis.

  11. Fish-T1K (Transcriptomes of 1,000 Fishes) Project: large-scale transcriptome data for fish evolution studies.

    Science.gov (United States)

    Sun, Ying; Huang, Yu; Li, Xiaofeng; Baldwin, Carole C; Zhou, Zhuocheng; Yan, Zhixiang; Crandall, Keith A; Zhang, Yong; Zhao, Xiaomeng; Wang, Min; Wong, Alex; Fang, Chao; Zhang, Xinhui; Huang, Hai; Lopez, Jose V; Kilfoyle, Kirk; Zhang, Yong; Ortí, Guillermo; Venkatesh, Byrappa; Shi, Qiong

    2016-01-01

    Ray-finned fishes (Actinopterygii) represent more than 50 % of extant vertebrates and are of great evolutionary, ecologic and economic significance, but they are relatively underrepresented in 'omics studies. Increased availability of transcriptome data for these species will allow researchers to better understand changes in gene expression, and to carry out functional analyses. An international project known as the "Transcriptomes of 1,000 Fishes" (Fish-T1K) project has been established to generate RNA-seq transcriptome sequences for 1,000 diverse species of ray-finned fishes. The first phase of this project has produced transcriptomes from more than 180 ray-finned fishes, representing 142 species and covering 51 orders and 109 families. Here we provide an overview of the goals of this project and the work done so far.

  12. 'Fish matters': the relevance of fish skin biology to investigative dermatology.

    Science.gov (United States)

    Rakers, Sebastian; Gebert, Marina; Uppalapati, Sai; Meyer, Wilfried; Maderson, Paul; Sell, Anne F; Kruse, Charli; Paus, Ralf

    2010-04-01

    Fish skin is a multi-purpose tissue that serves numerous vital functions including chemical and physical protection, sensory activity, behavioural purposes or hormone metabolism. Further, it is an important first-line defense system against pathogens, as fish are continuously exposed to multiple microbial challenges in their aquatic habitat. Fish skin excels in highly developed antimicrobial features, many of which have been preserved throughout evolution, and infection defense principles employed by piscine skin are still operative in human skin. This review argues that it is both rewarding and important for investigative dermatologists to revive their interest in fish skin biology, as it provides insights into numerous fundamental issues that are of major relevance to mammalian skin. The basic molecular insights provided by zebrafish in vivo-genomics for genetic, regeneration and melanoma research, the complex antimicrobial defense systems of fish skin and the molecular controls of melanocyte stem cells are just some of the fascinating examples that illustrate the multiple potential uses of fish skin models in investigative dermatology. We synthesize the essentials of fish skin biology and highlight selected aspects that are of particular comparative interest to basic and clinically applied human skin research.

  13. Fish allergens at a glance: variable allergenicity of parvalbumins, the major fish allergens.

    Science.gov (United States)

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1) isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases, and fish gelatin, seem to be important allergens. New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings were useful for the advancement of the IgE-based diagnosis and also for the management of fish allergies consisting of advice and treatment of fish-allergic patients.

  14. Fish allergens at a glance: Variable allergenicity of parvalbumins, the major fish allergens

    Directory of Open Access Journals (Sweden)

    Annette eKuehn

    2014-04-01

    Full Text Available Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1 isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases and fish gelatin, seem to be important allergens.New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings will be useful for the advancement of the IgE-based diagnosis but also for the management of fish allergies consisting of advice and treatment of fish-allergic patients.

  15. Perceptions of recreational fishing boat captains: knowledge and effects of fish consumption advisories.

    Science.gov (United States)

    Burger, J; Johnson, B B; Shukla, S; Gochfeld, M

    2003-04-01

    The impacts of fish consumption advisories on recreational and subsistence fishing, particularly in fresh waters, have been examined extensively. By contrast, little attention has focused on organized recreational fishing, such as from party and charter boats, and particularly for salt water fish. We interviewed 93 New Jersey boat captains to determine their knowledge about fish consumption advisories, and whether, in their opinion, clients knew of fish consumption advisories, and whether they thought advisories had an effect on recreational fishing and their businesses. Advisories were ranked by captains as a moderate influence on the success of their business, less so than number of fish caught, strength of the economy, overfishing by commercial boats, and management regulations. Only one boat captain had not heard warnings about eating fish, but what captains said they had heard was mixed in its accuracy and completeness. Clients expect captains to know about fish, and about half of boat captains said clients had asked about the safety of eating fish. Captains who felt advisories were affecting their businesses tended to fish for species without high levels of mercury (except for bluefish) or PCBs, the primary contaminants of concern for state advisories and federal advice. However, these captains worked closer to areas (e.g., Raritan Bay complex and New York Harbor) subject to advisories than did other captains, and were more prone to say that management regulations (e.g., fish size, creel limits, seasons) and marketing and advertising by the industry or state were strong influences on the success of their seasons. Comparing captains who thought advisories had some or great effect (60%) versus those reporting "no effect" (40%), there was no difference in the mean percentage of trips targeting high mercury species such as swordfish and shark. Many captains said they would or might post advisories, but 42% of the boat captains said they would not post consumption

  16. Fish Passage Center; Columbia Basin Fish and Wildlife Authority, 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, Michele (Columbia Basin Fish and Wildlife Authority, Fish Passage Center, Portland, OR)

    2001-06-01

    The year 2000 hydrosystem operations illustrated two main points: (1) that the NMFS Biological Opinion on the operations of the Federal Columbia River Power System (FCRPS) fish migration measures could not be met in a slightly below average water year, and; (2) the impacts and relationships of energy deregulation and volatile wholesale energy prices on the ability of the FCRPS to provide the Biological Opinion fish migration measures. In 2000, a slightly below average water year, the flow targets were not met and, when energy ''emergencies'' were declared, salmon protection measures were reduced. The 2000 migration year was a below average runoff volume year with an actual run off volume of 61.1 MAF or 96% of average. This year illustrated the ability of the hydro system to meet the migration protection measures established by the NMFS Biological Opinion. The winter operation of storage reservoirs was based upon inaccurate runoff volume forecasts which predicted a January-July runoff volume forecast at The Dalles of 102 to 105% of average, from January through June. Reservoir flood control drafts during the winter months occurred according to these forecasts. This caused an over-draft of reservoirs that resulted in less volume of water available for fish flow augmentation in the spring and the summer. The season Biological Opinion flow targets for spring and summer migrants at Lower Granite and McNary dams were not met. Several power emergencies were declared by BPA in the summer of 2000. The first in June was caused by loss of resources (WNP2 went off-line). The second and third emergencies were declared in August as a result of power emergencies in California and in the Northwest. The unanticipated effects of energy deregulation, power market volatility and rising wholesale electricity prices, and Californian energy deregulation reduced the ability of the FCRPS to implement fish protection measures. A Spill Plan Agreement was implemented in

  17. Duration of pregnancy in relation to fish oil supplementation and habitual fish intake: a randomised clinical trial with fish oil

    DEFF Research Database (Denmark)

    Olsen, Sjurdur Frodi; Østerdal, M L; Salvig, J D

    2007-01-01

    OBJECTIVE: To examine the effect of fish oil supplementation on duration of pregnancy, conditional on the woman's habitual fish intake. DESIGN: Multicentre 1:1 randomised clinical trial of effect of fish oil in a high-risk population of pregnant women in whom habitual fish intake was assessed...... at randomisation. SETTING: Nineteen university delivery wards in seven European countries. SUBJECTS: Pregnant women with preterm delivery, intrauterine growth retardation (IUGR), or pregnancy-induced hypertension (PIH) in a previous pregnancy (group 1, n=495); with twin pregnancies (group 2, n=367......); or with suspicion of IUGR or threatening preeclampsia in the current pregnancy (group 3, n=106). Women were stratified into low, middle, or high fish consumers. METHODS: The intervention group received fish oil capsules providing 2.7 g long-chain n-3 fatty acids per day (n-3 poly unsaturated fatty acids (PUFA...

  18. Habitat degradation and fishing effects on the size structure of coral reef fish communities.

    Science.gov (United States)

    Wilson, S K; Fisher, R; Pratchett, M S; Graham, N A J; Dulvy, N K; Turner, R A; Cakacaka, A; Polunin, N V C

    2010-03-01

    Overfishing and habitat degradation through climate change pose the greatest threats to sustainability of marine resources on coral reefs. We examined how changes in fishing pressure and benthic habitat composition influenced the size spectra of island-scale reef fish communities in Lau, Fiji. Between 2000 and 2006 fishing pressure declined in the Lau Islands due to declining human populations and reduced demand for fresh fish. At the same time, coral cover declined and fine-scale architectural complexity eroded due to coral bleaching and outbreaks of crown-of-thorns starfish, Acanthaster planci. We examined the size distribution of reef fish communities using size spectra analysis, the linearized relationship between abundance and body size class. Spatial variation in fishing pressure accounted for 31% of the variation in the slope of the size spectra in 2000, higher fishing pressure being associated with a steeper slope, which is indicative of fewer large-bodied fish and/or more small-bodied fish. Conversely, in 2006 spatial variation in habitat explained 53% of the variation in the size spectra slopes, and the relationship with fishing pressure was much weaker (approximately 12% of variation) than in 2000. Reduced cover of corals and lower structural complexity was associated with less steep size spectra slopes, primarily due to reduced abundance of fish < 20 cm. Habitat degradation will compound effects of fishing on coral reefs as increased fishing reduces large-bodied target species, while habitat loss results in fewer small-bodied juveniles and prey that replenish stocks and provide dietary resources for predatory target species. Effective management of reef resources therefore depends on both reducing fishing pressure and maintaining processes that encourage rapid recovery of coral habitat.

  19. Mathematical modeling of fish burger baking using fractional calculus

    Directory of Open Access Journals (Sweden)

    Bainy Eduarda M.

    2017-01-01

    Full Text Available Tilapia (Oreochromis sp. is the most important and abundant fish species in Brazil due to its adaptability to different environments. The development of tilapia-based products could be an alternative in order to aggregate value and increase fish meat consumption. However, there is little information available on fishburger freezing and cooking in the literature. In this work, the mathematical modeling of the fish burger baking was studied. Previously to the baking process, the fishburgers were assembled in cylindrical shape of height equal to 8mm and diameter 100mm and then baked in an electrical oven with forced heat convection at 150ºC. A T-type thermocouple was inserted in the burger to obtain its temperature profile at the central position. In order to describe the temperature of the burger during the baking process, lumped-parameter models of integer and fractional order and also a nonlinear model due to heat capacity temperature dependence were considered. The burger physical properties were obtained from the literature. After proper parameter estimation tasks and statistical validation, the fractional order model could better describe the experimental temperature behavior, a value of 0.91±0.02 was obtained for the fractional order of the system with correlation coefficient of 0.99. Therefore, with the better temperature prediction, process control and economic optimization studies of the baking process can be conducted.

  20. Intelligent Fish Freshness Assessment

    Directory of Open Access Journals (Sweden)

    Hamid Gholam Hosseini

    2008-01-01

    Full Text Available Fish species identification and automated fish freshness assessment play important roles in fishery industry applications. This paper describes a method based on support vector machines (SVMs to improve the performance of fish identification systems. The result is used for the assessment of fish freshness using artificial neural network (ANN. Identification of the fish species involves processing of the images of fish. The most efficient features were extracted and combined with the down-sampled version of the images to create a 1D input vector. Max-Win algorithm applied to the SVM-based classifiers has enhanced the reliability of sorting to 96.46%. The realisation of Cyranose 320 Electronic nose (E-nose, in order to evaluate the fish freshness in real-time, is experimented. Intelligent processing of the sensor patterns involves the use of a dedicated ANN for each species under study. The best estimation of freshness was provided by the most sensitive sensors. Data was collected from four selected species of fishes over a period of ten days. It was concluded that the performance can be increased using individual trained ANN for each specie. The proposed system has been successful in identifying the number of days after catching the fish with an accuracy of up to 91%.

  1. Why fishing magnifies fluctuations in fish abundance.

    Science.gov (United States)

    Anderson, Christian N K; Hsieh, Chih-hao; Sandin, Stuart A; Hewitt, Roger; Hollowed, Anne; Beddington, John; May, Robert M; Sugihara, George

    2008-04-17

    It is now clear that fished populations can fluctuate more than unharvested stocks. However, it is not clear why. Here we distinguish among three major competing mechanisms for this phenomenon, by using the 50-year California Cooperative Oceanic Fisheries Investigations (CalCOFI) larval fish record. First, variable fishing pressure directly increases variability in exploited populations. Second, commercial fishing can decrease the average body size and age of a stock, causing the truncated population to track environmental fluctuations directly. Third, age-truncated or juvenescent populations have increasingly unstable population dynamics because of changing demographic parameters such as intrinsic growth rates. We find no evidence for the first hypothesis, limited evidence for the second and strong evidence for the third. Therefore, in California Current fisheries, increased temporal variability in the population does not arise from variable exploitation, nor does it reflect direct environmental tracking. More fundamentally, it arises from increased instability in dynamics. This finding has implications for resource management as an empirical example of how selective harvesting can alter the basic dynamics of exploited populations, and lead to unstable booms and busts that can precede systematic declines in stock levels.

  2. Augmented fish health monitoring

    International Nuclear Information System (INIS)

    Michak, P.; Rogers, R.; Amos, K.

    1991-05-01

    The Bonneville Power Administration (BPA) initiated the Augmented Fish Health Monitoring project in 1986. This project was a five year interagency project involving fish rearing agencies in the Columbia Basin. Historically, all agencies involved with fish health in the Columbia Basin were conducting various levels of fish health monitoring, pathogen screening and collection. The goals of this project were; to identify, develop and implement a standardized level of fish health methodologies, develop a common data collection and reporting format in the area of artificial production, evaluate and monitor water quality, improve communications between agencies and provide annual evaluation of fish health information for production of healthier smolts. This completion report will contain a project evaluation, review of the goals of the project, evaluation of the specific fish health analyses, an overview of highlights of the project and concluding remarks. 8 refs., 1 fig., 4 tabs

  3. Monitoring of heavy metals in marine and freshwater fishes and nutritional evaluation of fish consumption

    International Nuclear Information System (INIS)

    Rina Mulyaningsih

    2014-01-01

    Fish is a food source of minerals. Uptake of heavy metals in fish could come from water, sediment and fish feed. Monitoring of minerals content and contaminants in fish has been carried out to evaluate nutrition and food safety, using neutron activation analysis techniques. Marine fish species that being analyzed are Kembung (Rastrelliger faughni), mackerel (Acanthocybium solandri), Tuna (Authis thazard) and freshwater fishes are Bawal (Colossoma macropomum), Nila (Oreochromis niloticus), Mas (Cyprinus carpio), sampled from 6 markets in North Jakarta. Monitoring results indicate that the essential minerals contained in fish are Fe, K, Na, Zn, Ca, Mg, and Se. Se and Ca concentrations in marine fish are higher than in freshwater fish. The concentration of other essential elements varies depending on the type of fish. The concentration of arsenic in marine fish is 3 times higher than that of freshwater fish; Hg and Cr content in all fish species were observed. From the evaluation of the adequacy of nutrition, with assuming a consumption of 86.68 g fish/day, for men aged 19 - 30 years, and referring to data from the Institute of Medicine USA, the Ca intake : 2.5 - 6.3; Cl : 1.5 - 3.3; Fe : 11.5 - 26.9; Na : 1.5 - 4.1; K : 3.4 - 6.7 and Zn 3.9 - 7.2% of the recommended value. Cr intake exceeds the recommended value, while As and Hg is not recommended in the food. In fact these metals contained in the studied fish, but the concentration is still below the value of standards issued by BPOM. (author)

  4. A Study of Fish Lice (Argulus Sp.) Infection in Freshwater Food Fish

    OpenAIRE

    Aalberg K.; Koščová L.; Šmiga Ľ.; Košuth P.; Koščo J.; Oros M.; Barčák D.; Lazar P.

    2016-01-01

    Argulus sp., commonly referred to as fish lice, are crustacean ectoparasites of fishes. The hematophagous parasites attach to and feed off the integument of their hosts. Outbreaks of epizootics have been reported worldwide, causing mass mortalities and having serious economic implications for fish farms and culture efforts. Argulus fish lice may also serve as vectors of infectious diseases and as intermediate hosts of other parasites. Two native European species, A. foliaceus and A. coregoni,...

  5. BIOTECHNOLOGY OF THE FISH AQUACULTURE

    Directory of Open Access Journals (Sweden)

    L. P. Buchatsky

    2013-12-01

    Full Text Available The latest progress in biotechnology on fish aquaculture and different modern methods of investigations for increasing of fish productivity in aquaculture are analyzed. Except for the applied aspect, the use of modern biotechnological methods of investigations opens new possibilities for fundamental researches of sex-determining mechanisms, polyploidy, distant hybridization, and developmental biology of bony fishes. Review contains examples of utilizing modern biotechnology methods to obtain transgenic fishes with accelerated growth and for designing surrogate fishes. Methods for receiving unisexual shoals of salmon and sturgeon female fishes with the view of obtaining a large quantity of caviar, as well as receiving sterile (triploid fishes are analyzed. Great attention is given to androgenesis, particularly to disperm one, in connection with the problem of conserving rare and vanishing fish species using only sperm genetic material. Examples how distant hybrids may be obtained with the use of disperm androgenesis and alkylated DNA are given. Methods of obtaining fish primordium germ cells, recent developments in cultivation of fish stem cells and their use in biotechnology, as well as ones of transplantation of oogonium and spermatogonium to obtain surrogate fishes. The examples of successful experiments on spermatogonial xenotransplantation and characteristic of antifreezing fish proteins and also the prospect of their practical usage are given.

  6. Reproductive ecology of a neotropical cichlid fish, Cichla monoculus (Osteichthyes: Cichlidae

    Directory of Open Access Journals (Sweden)

    S. Chellappa

    Full Text Available The reproductive ecology of the freshwater fish Cichla monoculus Spix, 1831 (Osteichthyes: Cichlidae was investigated in the Campo Grande Reservoir, Northeast Brazil. Rainfall, temperature, pH, dissolved oxygen and electrical conductivity of the water were recorded monthly. Fish collected on a monthly basis were measured, weighed, dissected, sexed and the stage of maturation of the gonads were assessed by macro and microscopic means. The semi-arid study region has short spells of rain of 2-3 months duration interspersed with dry seasons. A positive correlation was observed between rainfall and air and water temperatures and conductivity of the water. The study population had an extended spawning season, with peak reproductive activity coinciding with low water temperatures. Males were longer and heavier than females on average and were larger at onset of sexual maturity. The size frequency distributions of the oocytes indicate that C. monoculus is a multiple spawner with an estimated batch fecundity of 3100. Condition factor showed an inverse relationship in relation to gonad size during maturation in both sexes and spent fish were in poor condition. In mature males, lipid stores in the post-occipital cephalic protuberance, a secondary sexual characteristic developed during the reproductive phase, which depleted in spent individuals. The success of this fish is attributed to its reproductive capacity and to the phenotypic plasticity that allows it to adapt to the harsh ecological conditions that prevail in the semi-arid region of Northeast Brazil.

  7. Enzymes in Fermented Fish.

    Science.gov (United States)

    Giyatmi; Irianto, H E

    Fermented fish products are very popular particularly in Southeast Asian countries. These products have unique characteristics, especially in terms of aroma, flavor, and texture developing during fermentation process. Proteolytic enzymes have a main role in hydrolyzing protein into simpler compounds. Fermentation process of fish relies both on naturally occurring enzymes (in the muscle or the intestinal tract) as well as bacteria. Fermented fish products processed using the whole fish show a different characteristic compared to those prepared from headed and gutted fish. Endogenous enzymes like trypsin, chymotrypsin, elastase, and aminopeptidase are the most involved in the fermentation process. Muscle tissue enzymes like cathepsins, peptidases, transaminases, amidases, amino acid decarboxylases, glutamic dehydrogenases, and related enzymes may also play a role in fish fermentation. Due to the decreased bacterial number during fermentation, contribution of microbial enzymes to proteolysis may be expected prior to salting of fish. Commercial enzymes are supplemented during processing for specific purposes, such as quality improvement and process acceleration. In the case of fish sauce, efforts to accelerate fermentation process and to improve product quality have been studied by addition of enzymes such as papain, bromelain, trypsin, pepsin, and chymotrypsin. © 2017 Elsevier Inc. All rights reserved.

  8. Bibliographic review of works accomplished about irradiated chicken, fish and fish products , spices and condiments

    International Nuclear Information System (INIS)

    Bernardes, B.; Dias Filho, M.

    1983-07-01

    Table of foods that can be irradiated and its respective nominal doses are shown. Bibliographic reviews of works performed about irradiated chicken, fish and fish products, spices and condiments are shown. The irradiation purpose in chicken were to increase the shelf-life and to eliminate the pathogenic microorganism in chicken stored below 10 0 C; in fish and fish products the purposes were to control the insect infestation in dry-fish during the storage and the sell exposure to reduce the macrobian charge in packed and non packed fish and in fish products. To reduce pathogenic microorganism in packing and unpacking fish; in spices and condiments to control the insect infestation, to reduce the microbial contamination. (L.M.J.)

  9. Benzo[a]pyrene and Benzo[k]fluoranthene in Some Processed Fish and Fish Products

    Directory of Open Access Journals (Sweden)

    Olatunde S. Olatunji

    2015-01-01

    Full Text Available In this study, the concentration levels of the probable carcinogenic PAH fractions, benzo[a]pyrene (BaP and benzo[k]fluoranthrene (BkF in fillets of some processed fish species were investigated. Fish species comprising Merluccius poli (hake, Tyrsites atun (snoek, Seriola lalandi (yellow-tail and Brama brama (angel fish were bought in fish shops at Gordon’s Bay, Western Cape, South Africa. The fish were gutted, filleted and prepared for edibility by frying, grilling and boiling. Polycyclic aromatic hydrocarbons were extracted from each homogenized fish sample, cleaned-up using solid phase extraction (SPE, and analysed for the PAH fractions, BaP and BkF using a Gas Chromatograph coupled with a Flame Ionization Detector (GC-FID. The sum of the two PAHs (∑2PAH i.e., BaP and BkF ranged between 0.56 and 1.46 µg/kg, in all boiled, grilled and fried fish species. The fried fish extracts showed significantly higher (p < 0.05 abundance of ∑2PAH, than grilled and boiled fish. Dietary safety and PAHs toxicity was also discussed.

  10. Fish allergy in childhood.

    Science.gov (United States)

    Pascual, Cristina Y; Reche, Marta; Fiandor, Ana; Valbuena, Teresa; Cuevas, Teresa; Esteban, Manuel Martin

    2008-11-01

    Fish and its derived products play an important role in human nutrition, but they may also be a potent food allergen. Fish can be an ingested, contact, and inhalant allergen. Gad c I, a Parvalbumin, the major allergen in codfish, is considered as fish and amphibian pan-allergen. Prevalence of fish allergy appears to depend on the amount of fish eaten in the local diet. In Europe, the highest consumption occurs in Scandinavian countries, Spain and Portugal. In Spain, fish is the third most frequent allergen in children under 2 yr of age after egg and cow's milk. An adverse reaction to fish may be of non-allergic origin, due to food contamination or newly formed toxic products, but the most frequent type of adverse reactions to fish are immunologic-mediated reactions (allergic reactions). Such allergic reactions may be both IgE-mediated and non-IgE-mediated. Most cases are IgE-mediated, due to ingestion or contact with fish or as a result of inhalation of cooking vapors. Some children develop non-IgE-mediated type allergies such as food protein induced enterocolitis syndrome. The clinical symptoms related to IgE-mediated fish allergy are most frequently acute urticaria and angioedema as well as mild oral symptoms, worsening of atopic dermatitis, respiratory symptoms such as rhinitis or asthma, and gastrointestinal symptoms such as nausea and vomiting. Anaphylaxis may also occur. Among all the species studied, those from the Tunidae and Xiphiidae families appear to be the least allergenic.

  11. FISH and PNA FISH for the diagnosis of Q fever endocarditis and vascular infections.

    Science.gov (United States)

    Prudent, Elsa; Lepidi, Hubert; Angelakis, Emmanouil; Raoult, Didier

    2018-06-13

    Purpose. Endocarditis and vascular infections are common manifestations of persistent localized infection due to Coxiella burnetii and recently, fluorescence in situ hybridization (FISH) was proposed as an alternative tool for their diagnosis. In this study, we evaluated the efficiency of FISH in a series of valve and vascular samples infected by C. burnetii. Methods. We tested 23 C. burnetii -positive valves and thrombus samples obtained from patients with Q fever endocarditis. Seven aneurysms and thrombus specimens were retrieved from patients with Q fever vascular infection. Samples were analyzed by culture, immunochemistry and FISH with oligonucleotide and PNA probes targeting C. burnetii -specific 16S ribosomal RNA sequences. Results. Immunohistochemical analysis was positive for five (17%) samples with significantly more copies of C. burnetii DNA than the negative ones ( p= 0.02). FISH was positive for 13 (43%) samples and presented 43% and 40% sensitivity compared to qPCR and culture, respectively. PNA FISH detected C. burnetii in 18 (60%) samples and presented 60% and 55% sensitivity compared to qPCR and culture, respectively. Immunohistochemistry had 38% and 28% sensitivity compared to FISH and PNA FISH, respectively. Samples found positive by both immunohistochemistry and PNA FISH contained significantly more copies of C. burnetii DNA than the negative ones ( p= 0.03). Finally, PNA FISH was more sensitive than FISH (60% versus 43%) for the detection of C. burnetii Conclusion. We provide evidence that PNA FISH and FISH are important assays for the diagnosis of C. burnetii endocarditis and vascular infections. Copyright © 2018 American Society for Microbiology.

  12. Fish-Friendly Hydropower Turbine Development & Deployment: Alden Turbine Preliminary Engineering and Model Testing

    Energy Technology Data Exchange (ETDEWEB)

    Foust, J. [Voith Hydro, Inc., York, PA (USA); Hecker, G. [Alden Research Laboratory, Inc., Holden, MA (USA); Li, S. [Alden Research Laboratory, Inc., Holden, MA (USA); Allen, G. [Alden Research Laboratory, Inc., Holden, MA (USA)

    2011-10-01

    The Alden turbine was developed through the U.S. Department of Energy's (DOE's) former Advanced Hydro Turbine Systems Program (1994-2006) and, more recently, through the Electric Power Research Institute (EPRI) and the DOE's Wind & Water Power Program. The primary goal of the engineering study described here was to provide a commercially competitive turbine design that would yield fish passage survival rates comparable to or better than the survival rates of bypassing or spilling flow. Although the turbine design was performed for site conditions corresponding to 92 ft (28 m) net head and a discharge of 1500 cfs (42.5 cms), the design can be modified for additional sites with differing operating conditions. During the turbine development, design modifications were identified for the spiral case, distributor (stay vanes and wicket gates), runner, and draft tube to improve turbine performance while maintaining features for high fish passage survival. Computational results for pressure change rates and shear within the runner passage were similar in the original and final turbine geometries, while predicted minimum pressures were higher for the final turbine. The final turbine geometry and resulting flow environments are expected to further enhance the fish passage characteristics of the turbine. Computational results for the final design were shown to improve turbine efficiencies by over 6% at the selected operating condition when compared to the original concept. Prior to the release of the hydraulic components for model fabrication, finite element analysis calculations were conducted for the stay vanes, wicket gates, and runner to verify that structural design criteria for stress and deflections were met. A physical model of the turbine was manufactured and tested with data collected for power and efficiency, cavitation limits, runaway speed, axial and radial thrust, pressure pulsations, and wicket gate torque. All parameters were observed to fall

  13. Fish mucus metabolome reveals fish life-history traits

    Science.gov (United States)

    Reverter, M.; Sasal, P.; Banaigs, B.; Lecchini, D.; Lecellier, G.; Tapissier-Bontemps, N.

    2017-06-01

    Fish mucus has important biological and ecological roles such as defense against fish pathogens and chemical mediation among several species. A non-targeted liquid chromatography-mass spectrometry metabolomic approach was developed to study gill mucus of eight butterflyfish species in Moorea (French Polynesia), and the influence of several fish traits (geographic site and reef habitat, species taxonomy, phylogeny, diet and parasitism levels) on the metabolic variability was investigated. A biphasic extraction yielding two fractions (polar and apolar) was used. Fish diet (obligate corallivorous, facultative corallivorous or omnivorous) arose as the main driver of the metabolic differences in the gill mucus in both fractions, accounting for 23% of the observed metabolic variability in the apolar fraction and 13% in the polar fraction. A partial least squares discriminant analysis allowed us to identify the metabolites (variable important in projection, VIP) driving the differences between fish with different diets (obligate corallivores, facultative corallivores and omnivorous). Using accurate mass data and fragmentation data, we identified some of these VIP as glycerophosphocholines, ceramides and fatty acids. Level of monogenean gill parasites was the second most important factor shaping the gill mucus metabolome, and it explained 10% of the metabolic variability in the polar fraction and 5% in the apolar fraction. A multiple regression tree revealed that the metabolic variability due to parasitism in the polar fraction was mainly due to differences between non-parasitized and parasitized fish. Phylogeny and butterflyfish species were factors contributing significantly to the metabolic variability of the apolar fraction (10 and 3%, respectively) but had a less pronounced effect in the polar fraction. Finally, geographic site and reef habitat of butterflyfish species did not influence the gill mucus metabolome of butterflyfishes.

  14. Detection and identification of globally distributed mycobacterial fish pathogens in some ornamental fish in India.

    Science.gov (United States)

    Shukla, Shubhra; Sharma, Rolee; Shukla, Sanjeev Kumar

    2013-09-01

    Mycobacteriosis is a progressive disease of a wide range of wild and captive, marine and freshwater fish species. Conventional detection of fish Mycobacteria is based on histopathology, culture, and biochemical characteristics. The present study analyzed the occurrence of Mycobacteria in clinically ill ornamental fish of different species, from different places of India. In first group, 60 fish were examined for presence of granulomatous inflammation and acid-fast bacteria. Thirty-eight (63.34 %) fish were positive for granulomatous inflammations. Presences of acid-fast bacteria were detected in 27 (45 %) fish having granulomatous inflammation and in two (3.33 %) fish without granulomatous inflammation. In total, AFB were found in 29 (48.34 %) of the 60 fish examined. In second group, 20 fish having granulomatous inflammation, 12 (60 %) samples were positive using Ziehl-Neelsen (Z-N) staining and 11 (55 %) of them were culture positive. Eight (40 %) samples were Z-N negative but two (10 %) of them were culture positive. In total, 13 (65 %) of the 20 examined fish were culture positive. On the basis of biochemical tests and 16S rRNA sequencing, 13 isolates were identified: five as Mycobacterium fortuitum, five as Mycobacterium gordonae, and three as Mycobacterium chelonae. In comparison of two decontamination methods, 2 % HCl treatment was better than 4 % NaOH treatment. Mycobacteria recovery from decontaminated samples was significantly high on Lowenstein-Jensen medium compared to Middlebrook 7H11 agar and Stonebrink (SB) media. The disease is transmissible from fish to fish and also from fish to human, so the significance of Mycobacteria in ornamental fish should not be overlooked.

  15. Immunostimulants in fish diets

    Science.gov (United States)

    Gannam, A.L.; Schrock, R.M.

    1999-01-01

    Various immunostimulants and their methods of application in fish culture are examined in this review. Important variables such as life stage and innate disease resistance of the fish; immunostimulant used, its structure and mode of action; and the fish's environment are discussed. Conflicting results have been published about the efficacy of immunostimulants in fish diets. Some researchers have had positive responses demonstrated as increased fish survival, others have not. Generally, immunostimulants enhance individual components of the non-specific immune response but that does not always translate into increased fish survival. In addition, immunostimulants fed at too high a dose or for too long can be immunosuppressive. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: getinfo@haworthpressinc.com ].

  16. Fish and hydroelectricity

    International Nuclear Information System (INIS)

    Zorpette, G.

    1990-01-01

    This paper reports on the problems that hydroelectric plants have regarding fish populations. The utilities that operate these plants are finding that accommodating migrating fish presents unique engineering challenges, not the least of which involves designing and building systems to protect fish species whose migratory behavior remains something of a mystery. Where such systems cannot be built, the status of hydroelectric dams may be in doubt, as is now the case with several dams in the United States. A further twist in some regions in the possibility that certain migratory fish will be declared threatened or endangered-a development that could wreak havoc on the hydroelectric energy supply in those regions

  17. Fish impingement at estuarine power stations and its significance to commercial fishing

    International Nuclear Information System (INIS)

    Turnpenny, A.W.H.

    1989-01-01

    The abstraction of cooling water (CW) at power stations sited on tidal waters inevitably leads to mortalities of some fish which are drawn in with the CW supply and become impinged on the intake screens. These fish are predominantly 0- or 1-group juveniles which, owing to their small size, are unable to resist intake currents. Commercial fishermen often object to the fact that juvenile fish are killed in this way. Their concern stems from the fact that in order to protect stocks, commercial fishing is restricted to fish which are above a statutory minimum landing size, whereas the majority of fish killed by impingement are below this size. This Report considers the significance of impingement mortalities at four estuarine sites in Britain for six commercially important species. Life tables are used to establish expected survival trajectories for each species and to compute reproductive potential. Each fish killed on intake screens is then considered in terms of the fraction of the reproductive potential of a single adult at maturity, and is ascribed an 'adult equivalent' value. Total catches of mixed juveniles and adults are then presented as 'adult equivalent' values. (author)

  18. Emerging role of phenolic compounds as natural food additives in fish and fish products.

    Science.gov (United States)

    Maqsood, Sajid; Benjakul, Soottawat; Shahidi, Fereidoon

    2013-01-01

    Chemical and microbiological deteriorations are principal causes of quality loss of fish and fish products during handling, processing, and storage. Development of rancid odor and unpleasant flavor, changes of color and texture as well as lowering nutritional value in fish can be prevented by appropriate use of additives. Due to the potential health hazards of synthetic additives, natural products, especially antioxidants and antimicrobial agents, have been intensively examined as safe alternatives to synthetic compounds. Polyphenols (PP) are the natural antioxidants prevalent in fruits, vegetables, beverages (tea, wine, juices), plants, seaweeds, and some herbs and show antioxidative and antimicrobial activities in different fish and fish products. The use of phenolic compounds also appears to be a good alternative for sulphiting agent for retarding melanosis in crustaceans. Phenolic compounds have also been successfully employed as the processing aid for texture modification of fish mince and surimi. Thus, plant polyphenolic compounds can serve as potential additives for preventing quality deterioration or to retain the quality of fish and fish products.

  19. Improving fish survival through turbines

    International Nuclear Information System (INIS)

    Ferguson, J.W.

    1993-01-01

    Much of what is known about fish passage through hydroturbines has been developed by studying migratory species of fish passing through large Kaplan turbine units. A review of the literature on previous fish passage research presented in the accompanying story illustrates that studies have focused on determining mortality levels, rather than identifying the causal mechanism involved. There is a need for understanding how turbine designs could be altered to improve fish passage conditions, how to retrofit existing units, and how proposed hydro plant operational changes may affect fish survival. The US Army Corps of Engineers has developed a research program to define biologically based engineering criteria for improving fish passage conditions. Turbine designs incorporating these criteria can be evaluated for their effects on fish survival, engineering issues, costs, and power production. The research program has the following objectives: To gain a thorough knowledge of the mechanisms of fish mortality; To define the biological sensitivities of key fish species to these mechanisms of mortality; To develop new turbine design criteria to reduce fish mortality; To construct prototype turbine designs, and to test these designs for fish passage, hydro-mechanical operation, and power production; and To identify construction and power costs associated with new turbine designs

  20. Fish as bioindicators in aquatic environmental pollution assessment: A case study in Lake Victoria wetlands, Uganda

    Science.gov (United States)

    Naigaga, I.; Kaiser, H.; Muller, W. J.; Ojok, L.; Mbabazi, D.; Magezi, G.; Muhumuza, E.

    Growing human population and industrialization have led to the pollution of most aquatic ecosystems and consequent deterioration in environmental water quality. Indicator organisms are needed to improve assessment programmes on the ecological impacts of anthropogenic activities on the aquatic environment. Fish have been widely documented as useful indicators of environmental water quality because of their differential sensitivity to pollution. This study investigated the environmental water quality of selected wetland ecosystems using fish as biological indicators. Fish community structure in relation to water quality was assessed in five wetlands along the shoreline of Lake Victoria from August 2006 to June 2008. Four urban wetlands were variedly impacted by anthropogenic activities while one rural wetland was less impacted, and served as a reference site. Fish species diversity, abundance and richness were assessed, and canonical correspondence analysis (CCA) was used to evaluate the relationship between the fish communities and environmental variables. Results revealed that urban effluent impacted negatively on water quality and consequently the fish community structure. A total of 29 fish species were recorded throughout the study with the lowest number of 15 species recorded in the most impacted site. Shannon diversity and Margalef species richness indices were highest at the references site and lowest at the most impacted site. Wetland haplochromis species dominated the reference site, while oreochromis species dominated the most impacted site. The inshore locations registered higher species diversity and low species richness than the offshore locations. Low dissolved oxygen, pH, secchi depth and high electrical conductivity, total phosphorous, and total nitrogen were strongly associated with the effluent-impacted sites and greatly influenced the fish community structure. This study recommends the use of fish as valuable biological indicators in aquatic

  1. Selenium poisoning of fish by coal ash wastewater in Herrington Lake, Kentucky.

    Science.gov (United States)

    Lemly, A Dennis

    2018-04-15

    Selenium pollution from the E.W. Brown Electric Generating Station was investigated in Herrington Lake, KY. Coal ash wastewater is discharged as surface water overflow from ash disposal ponds into the lake via a National Pollutant Discharge Elimination System permit issued by the Kentucky Division of Water, but the permit does not restrict or limit the amount of selenium released. Unpermitted discharges occur from seeps and drainage through leaks in ash pond dams. Together, these discharges have resulted in selenium concentrations in water, sediment, benthic macroinvertebrates, and fish that are 2-9 times the level that is toxic for fish reproduction and survival. A large proportion (12.2%, or 25 times background) of juvenile largemouth bass (Micropterus salmoides, the only species examined) exhibited spinal and/or craniofacial malformations that are consistent with selenium poisoning. Teratogenic Deformity Index values indicated a 3.05% population-level impact on the bass fishery, with total selenium-induced mortality (including pre-swimup mortality) estimated to be in excess of 25% per year. These findings confirm that coal ash discharges into Herrington Lake are contributing selenium to the Lake that is poisoning fish. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Persistent Organohalogens in Paired Fish Fillet and Eggs: Implications for Fish Consumption Advisories.

    Science.gov (United States)

    Zhang, Xianming; Gandhi, Nilima; Bhavsar, Satyendra P

    2016-04-13

    Fish consumption is associated with both health benefits from high-quality proteins, minerals, vitamins, and fatty acids and risks from contaminants in fish. Fish consumption advisories are issued by many government agencies to keep exposure to contaminants at a safe level. Such advisories are typically based on fillets and neglect consumption of other fish parts such as eggs by certain subpopulations. To evaluate potential for dietary exposure to toxic organic chemicals via fish eggs, we analyzed polybrominated diphenyl ethers (PBDEs), polychlorinated naphthalenes (PCNs), dioxin-like polychlorinated biphenyls (dlPCBs), and polychlorinated dibenzodioxins/furans (PCDD/Fs) in paired fillet and eggs of fish from a tributary to Lake Ontario, one of the North American Great Lakes. All wet weight based concentrations in fish eggs were statistically higher than in the paired fillet samples. In fish eggs, concentrations of Σ14PBDEs, Σ14PCNs, and Σ12dlPCBs were 41-118, 0.3-1.7, and 30-128 ng/g wet weight (ww), respectively; Σ3PCDD/Fs and total (dlPCB+ PCDD/Fs) toxic equivalents (TEQs) were 4-22 and 9-54 pg/g ww, respectively. In fillet samples, Σ14PBDEs, Σ14PCNs, and Σ12dlPCBs were 4-116, 0.05-0.66, and 6-85 ng/g, respectively; Σ3PCDD/Fs and TEQs were 2-10 and 3.4-31 pg/g ww, respectively. In contrast, the fillets had higher lipid normalized concentrations than the paired egg samples, suggesting that these chemicals did not reach equilibrium between the fillets and eggs. Accordingly, measured concentrations in eggs or empirical relationship with fillet rather than prediction from equilibrium partitioning model should be used to evaluate contaminant exposure via consumption of fish eggs. For fatty fish from the lower Great Lakes area, we suggest one fillet meal be reduced from the advised fish consumption frequency for consumptions of 207 ± 37, 39 ± 2, 105 ± 51, and 119 ± 9 g fish eggs of brown trout, Chinook salmon, Coho salmon, and rainbow trout, respectively.

  3. Fishing effects on energy use by North Sea fishes

    NARCIS (Netherlands)

    Jennings, S.; Hal, van R.; Hiddink, J.G.; Maxwell, T.A.D.

    2008-01-01

    Fishing affects patterns of energy use in fish populations, as demonstrated by changes in population energy consumption and the size and age when energy demands are greatest. We compare theoretical predictions and observed patterns of energy use (expressed as the primary production required to

  4. Multiple cues produced by a robotic fish modulate aggressive behaviour in Siamese fighting fishes.

    Science.gov (United States)

    Romano, Donato; Benelli, Giovanni; Donati, Elisa; Remorini, Damiano; Canale, Angelo; Stefanini, Cesare

    2017-07-05

    The use of robotics to establish social interactions between animals and robots, represents an elegant and innovative method to investigate animal behaviour. However, robots are still underused to investigate high complex and flexible behaviours, such as aggression. Here, Betta splendens was tested as model system to shed light on the effect of a robotic fish eliciting aggression. We evaluated how multiple signal systems, including a light stimulus, affect aggressive responses in B. splendens. Furthermore, we conducted experiments to estimate if aggressive responses were triggered by the biomimetic shape of fish replica, or whether any intruder object was effective as well. Male fishes showed longer and higher aggressive displays as puzzled stimuli from the fish replica increased. When the fish replica emitted its full sequence of cues, the intensity of aggression exceeded even that produced by real fish opponents. Fish replica shape was necessary for conspecific opponent perception, evoking significant aggressive responses. Overall, this study highlights that the efficacy of an artificial opponent eliciting aggressive behaviour in fish can be boosted by exposure to multiple signals. Optimizing the cue combination delivered by the robotic fish replica may be helpful to predict escalating levels of aggression.

  5. Growth performance of pearl goldfish juvenile carassius auratus cultured in 3 ppt salinity with different exposure time of electric field

    Directory of Open Access Journals (Sweden)

    Kukuh Nirmala

    2015-04-01

    Full Text Available ABSTRACTGrowth rate of pearl goldfish juvenile Carassius auratus relatively slow to reach market size which will take approximately three months. To accelerate its growth can be done by providing exposure of the fish to low-power electric fields (10 V via 3 ppt salinity water, with the goal of providing the close isoosmotic conditions, and also to streamline the flow of electricity from the electrodes to the body of the fish. This study aims to calculate the survival and growth rate of pearl goldfish juvenile of S sizes (2‒4 cm of body length which were maintained at 3 ppt salinity water and treated by different exposure time of electric field (zero, two, four, and six minutes before feeding with 10 volt electric power. Fish were cultured at a density of 2 fish/L in the (20×30×20 cm3 aquaria in volume of 6 L of water. Test fish had an average body length of 4.11±0.05 cm and the average body weight of 2.89±0.05 g. Exposure time of electric field were zero, two, four, and six minutes before the fish are fed, performed every day as much as three times i.e. morning, afternoon, and evening. The research design used was completely randomized design with four treatments, namely 0, 2, 4, and 6 (time for exposure is zero/control, two, four, and six minute with three replications. The results show test fishes exposed to 10 volt electrical field for zero, two, four, and six minutes, have no significant effect on survival rate (P>0.05. For growth performance, four minute exposure treatment gives the best results compared to controls (P<0.05, supported by an increase in the percentage of the ratio of gut length to body length of the fish and higher feed efficiency.Keywords: long exposure to the electric field, growth performance, pearl goldfishABSTRAKPertumbuhan benih ikan hias maskoki mutiara Carassius auratus relatif lambat, karena untuk mencapai ukuran jual memerlukan waktu sekitar tiga bulan. Untuk mempercepat pertumbuhannya dapat dilakukan dengan

  6. Turbine related fish mortality

    International Nuclear Information System (INIS)

    Eicher, G.J.

    1993-01-01

    A literature review was conducted to assess the factors affecting turbine-related fish mortality. The mechanics of fish passage through a turbine is outlined, and various turbine related stresses are described, including pressure and shear effects, hydraulic head, turbine efficiency, and tailwater level. The methodologies used in determining the effects of fish passage are evaluated. The necessity of adequate controls in each test is noted. It is concluded that mortality is the result of several factors such as hardiness of study fish, fish size, concentrations of dissolved gases, and amounts of cavitation. Comparisons between Francis and Kaplan turbines indicate little difference in percent mortality. 27 refs., 5 figs

  7. Immunity to Fish Rhabdoviruses

    OpenAIRE

    Purcell, Maureen K.; Laing, Kerry J.; Winton, James R.

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabd...

  8. The prevalence of parasites in ornamental fish from fish market in Medan

    Science.gov (United States)

    Dewi, R. R.; Desrita; Fadhilla, A.

    2018-02-01

    Parasites still become the major problem in ornamental fish as the fast grown of its trading in Indonesia. Parasites causes diseases in ornamental fish hence followed by death and reducing its appearence. In this study, the prevalence of parasites in 100 apparently healthy ornamental fishes namely Guppy (Poecilia reticulate) and Goldfish (Carrasius auratus) were determined. The method of this research used was survey in local fish market in Medan from March to May 2017 The aim of this study was to determine the parasite that infects aquarium fishes and find out its prevalence. For this purpose, ornamental fishes were examined for parasites from their skin, fin, gill and intestine using wet mount method under a light microscope. The survey result showed that parasites that infect Guppy and Goldfish were Monogenea (Dactylogyrus sp and Gyrodactylus sp) in their skin and gill, Protozoa (piscinodinium sp) in their gill and Nematoda (Capillaria sp) in abdominal cavity. Prevalence rate of parasites that attack Guppy in Medan is Dactylogyrus sp (8%), Gyrodactylus sp (14 %), Piscinodinium sp (6%) and Capillaria sp (8%). Then, prevalence rate of Capilaria sp that attack Goldfish is 4%. The conclusion of this work revealed that the prevalence rate of ectoparasite and endoparasites in ornamental fishes in Medan had the low rate as well as there was no pathological findings is observed. However, these parasites could be a harmful parasitic diseases in case there is the changes in aquarium environment and improper fish handling.

  9. Fish reproduction

    National Research Council Canada - National Science Library

    Rocha, Maria João; Arukwe, Augustine; Kapoor, B. G

    2008-01-01

    ... of reproductive systems is essential for such studies. Fishes comprise over 28,000 species, with a remarkable variability in morphology, physiology and environmental adaptation. Knowledge on fish reproduction is scattered across numerous sources that shows a dynamic research field. The Editors believe it to be an opportune moment for a...

  10. Monetary values of freshwater fish and fish-kill counting guidelines

    National Research Council Canada - National Science Library

    1982-01-01

    .... The product is a set of documented monetary values of freshwater fish that may be used, in conjunction with standard sampling programs outlined in Part II of this book, to assess the value of fish...

  11. Soluble protein isolated from low cost fish and fish wastes

    OpenAIRE

    Lekshmy Nair, A.; Gopakumar, K.

    1982-01-01

    The method of preparation, composition, amino acid content, protein efficiency ratio and areas of possible application of water soluble protein isolates from low cost fish and fish wastes are discussed in detail in this communication.

  12. Quantifying relative fishing impact on fish populations based on spatio-temporal overlap of fishing effort and stock density

    DEFF Research Database (Denmark)

    Vinther, Morten; Eero, Margit

    2013-01-01

    Evaluations of the effects of management measures on fish populations are usually based on the analyses of population dynamics and estimates of fishing mortality from stock assessments. However, this approach may not be applicable in all cases, in particular for data-limited stocks, which may...... GAM analyses to predict local cod densities and combine this with spatio-temporal data of fishing effort based on VMS (Vessel Monitoring System). To quantify local fishing impact on the stock, retention probability of the gears is taken into account. The results indicate a substantial decline...... in the impact of the Danish demersal trawl fleet on cod in the Kattegat in recent years, due to a combination of closed areas, introduction of selective gears and changes in overall effort....

  13. Technical Suitability and Static Stability of Sungkur Fishing Boats for Fish and Shrimp Catching

    Science.gov (United States)

    Rusmilyansari; Rosadi, E.; Iriansyah

    2017-10-01

    Sungkur fishing gear is operated actively on one the side of fishing boat, which requires technical suitability and fishing gear stability to ensure success in fish catching. This is a case study which aimed to analyze some technical issues related to the boat, boat’s hydrostatic parameters, and the boat’s stability. The data were collected though observation, measuring the boat to obtain the offset table. The data were analyzed numerically and descriptively. The data were processed with technical formula, Microsoft Office’s Excel software, graphic display, minitab, statistical data processing, and maxsurf program. The research results showed that: (1) the sungkur fishing boat dimensional ratio L/B (6.47 - 7.00); L/D (10.90 - 11.20) and B/D (1.60 - 1.668) is within the range value of Indonesian fishing boats suitable to operate the fishing gear by towing or dragging. However, during fish catching operation, there have been problems in a hydrodynamic force due to the fishing gear movement, which affect the fish catching efficiency. (2) The boat’s coefficient of fineness is in the fine type shape; the displacement on each waterline has increased; the loads of the boat are getting larger following the increase of waterline from one to five; this is also shown from the increasing midship area value. Ton per centimeter immersion to change wl 1 by 1 cm needs 0.04 tons of weight. (3) Sungkur fishing boat have a good static stability, which is proven by the positive value of angle of maximum GZ by 79.1 - 83.6. In other words, the boat has the ability to return to its original position after tilting; however, stability dynamics happens because fishing gear operation are located on just one side of boat.

  14. Contaminants in popular farmed fish consumed in The Netherlands and their levels in fish feedContaminants in popular farmed fish consumed in The Netherlands and their levels in fish feed

    NARCIS (Netherlands)

    Leeuwen, van S.; Velzen, van M.; Swart, K.; Veen, van der I.; Traag, W.A.; Spanjer, M.; Scholten, J.; Rijn, van H.

    2008-01-01

    Investigated is a wide range of pollutants in the top five consumed fish in the Netherlands (salmon, trout, tilapia, pangasius and shrimps). Farmed fish samples were collected from different sources (supermarkets, fish stores, markets and suppliers for restaurants) and analysed for PCDD/Fs, PCBs,

  15. Perspectives on fish impingement

    International Nuclear Information System (INIS)

    Sharma, R.K.

    1977-01-01

    Data on fish impingement and related parameters are being gathered at a large number of power stations throughout the country at substantial monetary and manpower costs. A national survey of fish impingement at power plants was conducted and much of the information compiled in a standardized format--an effort that we think will aid in planning improvements in the design, siting, and operation of the cooling-water intakes. This paper examines the objectives of the fish impingement studies, monitoring programs, variables affecting fish impingement, siting and design criteria, state-of-the-art of screening systems, and suggestions for meeting 316(b) requirements. It also discusses where the emphasis should be placed in future fish-impingement related activities

  16. A Hydropower Biological Evaluation Toolset (HBET) for Characterizing Hydraulic Conditions and Impacts of Hydro-Structures on Fish

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Hongfei; Deng, Zhiqun; Martinez, Jayson; Fu, Tao; Duncan, Joanne; Johnson, Gary; Lu, Jun; Skalski, John; Townsend, Richard; Tan, Li

    2018-04-01

    Currently, approximately 16% of the world’s electricity and over 80% of the world’s renewable electricity is generated from hydropower resources, and there is potential for development of a significant amount of new hydropower capacity. However, in practice, realizing all the potential hydropower resource is limited by various factors, including environmental effects and related mitigation requirements. That is why hydropower regulatory requirements frequently call for targets to be met regarding fish injury and mortality rates. Hydropower Biological Evaluation Toolset (HBET), an integrated suite of software tools, is designed to characterize hydraulic conditions of hydropower structures and provide quantitative estimates of fish injury and mortality rates due to various physical stressors including strike, pressure, and shear. HBET enables users to design new studies, analyze data, perform statistical analyses, and evaluate biological responses. In this paper, we discuss the features of the HBET software and describe a case study that illustrates its functionalities. HBET can be used by turbine manufacturers, hydropower operators, and regulators to design and operate hydropower systems that minimize ecological impacts in a cost-effective manner.

  17. Fish and mussels: importance of fish for freshwater mussel conservation

    Directory of Open Access Journals (Sweden)

    Ronaldo Sousa

    2015-12-01

    Full Text Available Co-extinctions have received trivial consideration in discussions about the global conservation crisis, even though recent studies have emphasised their importance. This situation is even more pronounced in freshwater ecosystems where this phenomenon is largely unrecognized. In this presentation we explore the role of fish for freshwater mussels’ conservation. Freshwater mussels’ need fish as a host to complete their life cycle and given this premise is expected that changes in the fish community due to species extinctions or additions may have great effects. We reviewed the published information and we found: 1 that most of the studies were published in the last few years; 2 that most of the studies were performed in North America (69%, which is probably due to the high number of endemic threatened species in this continent; 3 that most of the mussel species that are specialists in fish hosting are listed as vulnerable or endangered (55%; 4 most studies were performed in laboratory (83% and 5 that the majority of studies were focused on life cycle or on identifying suitable fish hosts of freshwater mussel species with few studies focusing on threats. Since the interaction between fish and freshwater mussels can be easily disrupted and serious threats to this interaction have arisen (e.g. loss and fragmentation of habitat, changes in river flow, climate change, introduction of invasive species, pollution a more holistic approach is needed to find the best management strategies to conserve these animals. In addition, more field studies are required and more information on African, South American and Asian species is essential. Neglect the possible fundamental role of fish in the decline or extinction of freshwater mussels may impair the success of any measure devoted to their conservation; therefore, this issue cannot be ignored.

  18. Effect of Recreational Fish Feeding on Reef Fish Community ...

    African Journals Online (AJOL)

    ... that the reaction to bread at feeding sites was quicker than at control sites, which indicates that some species learn to feed on this novel source of food. Keywords:human-animal interactions, reef fish, recreational fish feeding, tourism impacts, MPAs, coral reefs, Kenya West Indian Ocean Journal of Marine Science Vol.

  19. Impacts of electromagnetic fields associated with marine and hydrokinetic surrogate technologies on fish movements and behaviors.

    Energy Technology Data Exchange (ETDEWEB)

    Claisse, Jeremy T. [Vantuna Research Group, Los Angeles, CA (United States); Pondella, Daniel J. [Vantuna Research Group, Los Angeles, CA (United States); Williams, Chelsea M. [Vantuna Research Group, Los Angeles, CA (United States); Zahn, Laurel A. [Vantuna Research Group, Los Angeles, CA (United States); Williams, Jonathan P. [Vantuna Research Group, Los Angeles, CA (United States)

    2015-09-30

    Marine and hydrokinetic energy (MHK) and offshore wind devices are being developed and deployed in U.S. and international waters. Electric current flowing through subsea transmission cables associated with these devices will generate electromagnetic fields (EMF), which may interact with, and potentially impact, marine fishes. Some marine fishes can detect electric and/or magnetic fields and use them to navigate, orientate, and sense prey, mates and predators. Over the past five years there have been multiple comprehensive reviews and studies evaluating the potential vulnerability of marine fishes to EMF produced by MHK devices. Most documented effects involve sub-lethal behavioral responses of individual fish when in close proximity to EMF (e.g., fish being repelled by or attracted to fields). These reviews reach conclusions that the current state of research on this topic is still in its infancy and evaluations of potential impacts are associated with great uncertainty. A variety of MHK technologies are likely to be considered for deployment offshore of the Hawaiian Islands, and there is a need to be able to better predict and assess potential associated environmental impacts. The goal of this study was to provide a complementary piece to these previous reviews (e.g., Normandeau et al. 2011) by focusing on marine fish species in the Hawaii region. We compiled the relevant available information, then prioritized fish species as candidates for various paths of future research. To address this, we first developed a list of Hawaii Region Focal Species, which included fishes that are more likely to be sensitive to EMF. We then compiled species-specific information available in the literature on their sensitivity to EMF, as well as life history, movement and habitat use information that could inform an analysis of their likelihood of encountering EMF from subsea cables associated with MHK devices. Studies have only documented EMF sensitivity in 11 of the marine fish

  20. Fish losses due to bacterial flora and infections of fishes in Kainji ...

    African Journals Online (AJOL)

    This paper assesses the losses incurred as a result of bacterial flora and infection in captured and cultured fish. The role played by these bacterial flora on the overall quality and health of fish is discussed. Bacteria have been reported to cause diseases in ponds and increase in the spoilage rate of raw and preserved fish in ...

  1. Effects of water quality alterations on fish behavior

    International Nuclear Information System (INIS)

    Gray, R.H.; Haynes, J.M.; Montgomery, J.C.; Genoway, R.G.; Barraclough, S.A.; Anderson, D.R.; Thatcher, T.O.; Bean, R.M.; Page, T.L.

    1977-01-01

    Objectives of this project are to study behavioral patterns of ecologically or economically valuable fish. Information on sensory--avoidance behavior, or preferential foraging habits, if definitively established by systematic observation can be constructively used in both outfall and water intake design to ameliorate potentially noxious disturbances caused by these structures. The work is applicable to both nuclear and fossil fuel-fired steam electric plants. The instantaneous response of juvenile chinook salmon encountering a simulated river thermal plume interface was also evaluated in a model raceway. Tests indicate that juvenile chinook salmon perceive and avoid discharge temperatures greater than 9 to 11 0 C above ambient, regardless of acclimation temperature. Chlorine is a major chemical compound to reduce biofouling in steam electric power plants. Chlorination of large volumes of cooling waters poses the problem of the formation of chlorination by-products discharged to natural water systems. Long-term bioassays, both fresh and salt water, are underway with indepth analytical chemistry to determine the magnitude of the chlorination by-product problem

  2. Distance from a fishing community explains fish abundance in a no-take zone with weak compliance.

    Science.gov (United States)

    Advani, Sahir; Rix, Laura N; Aherne, Danielle M; Alwany, Magdy A; Bailey, David M

    2015-01-01

    There are numerous examples of no-take marine reserves effectively conserving fish stocks within their boundaries. However, no-take reserves can be rendered ineffective and turned into 'paper parks' through poor compliance and weak enforcement of reserve regulations. Long-term monitoring is thus essential to assess the effectiveness of marine reserves in meeting conservation and management objectives. This study documents the present state of the 15-year old no-take zone (NTZ) of South El Ghargana within the Nabq Managed Resource Protected Area, South Sinai, Egyptian Red Sea. Previous studies credited willing compliance by the local fishing community for the increased abundances of targeted fish within the designated NTZ boundaries compared to adjacent fished or take-zones. We compared benthic habitat and fish abundance within the NTZ and the adjacent take sites open to fishing, but found no significant effect of the reserve. Instead, the strongest evidence was for a simple negative relationship between fishing pressure and distance from the closest fishing village. The abundance of targeted piscivorous fish increased significantly with increasing distance from the village, while herbivorous fish showed the opposite trend. This gradient was supported by a corresponding negative correlation between the amount of discarded fishing gear observed on the reef and increasing distance from the village. Discarded fishing gear within the NTZ suggested decreased compliance with the no-take regulations. Our findings indicate that due to non-compliance the no-take reserve is no longer functioning effectively, despite its apparent initial successes and instead a gradient of fishing pressure exists with distance from the nearest fishing community.

  3. THE CLASSIC WAY OF FISH PROCESSING

    Directory of Open Access Journals (Sweden)

    Đurica Kalember

    1998-04-01

    Full Text Available Today's population faces great difficulties in fish marketing, although it is very valuable food. The classic supply with fresh fish has little influence on its consumption, which is not remarkable anyhow. Therefore one shulud be reminded on the classic, almost forgotten, ways of fish processing that can substantially increase fish assortment and improve its distribution. After cleaning and cutting the fish (primary procedures in its processing, comes salting, after which the salted fish can become an end-product or it can be one of many semi-products in the fish production chain. The most common methods of fish salting are dry-salting, dry-wet-salting (Greek-Dalmatian and wet-salting (pickling. The aim of fish drying is its dehydratation. Our country has the experience of traditional drying, sun-drying and natural drying of fish. Each of these has its own special qualities, depending on the fish species and the drying temperature. Smoked fish gets a very distinctive and spicy aroma and a specific colour. There are two kinds of smoking - cold and warm - based on the smoke derived from burning some special trees or, lately, from smoke preparations. Marinades are old procedures of fish processing in acetic acid and specific spices which can be prepared cold, fried or cooked. Fish-roe of some specific fish species has a special value and is considered a delicacy. The most precious black caviar is derived from the sturgeon roe and some of its related species.

  4. One Fish, Two Fish, Redfish, You Fish!

    Science.gov (United States)

    White, Katherine; Timmons, Maryellen; Medders, Paul

    2011-01-01

    The recreational fishing activity presented in this article provides a hands-on, problem-based experience for students; it unites biology, math, economics, environmental policy, and population dynamics concepts. In addition, the activity allows students to shape environmental policy in a realistic setting and evaluate their peers' work. By…

  5. Scorpion fish sting

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/002849.htm Scorpion fish sting To use the sharing features on this page, please enable JavaScript. Scorpion fish are members of the family Scorpaenidae, which includes ...

  6. A Study of Fish Lice (Argulus Sp. Infection in Freshwater Food Fish

    Directory of Open Access Journals (Sweden)

    Aalberg K.

    2016-09-01

    Full Text Available Argulus sp., commonly referred to as fish lice, are crustacean ectoparasites of fishes. The hematophagous parasites attach to and feed off the integument of their hosts. Outbreaks of epizootics have been reported worldwide, causing mass mortalities and having serious economic implications for fish farms and culture efforts. Argulus fish lice may also serve as vectors of infectious diseases and as intermediate hosts of other parasites. Two native European species, A. foliaceus and A. coregoni, as well as the invasive Japanese fish louse A. japonicus, have previously been recorded in Slovakia. This study investigated samples collected at fish farms and culture sites of Common carp (Cyprinus carpio L., Pike-perch (Sander lucioperca L. and Brook trout (Salvelinus fontinalis M. in Eastern Slovakia, as well as samples collected from live fish imported to the Slovak Republic. A quantitative description of the of Argulus sp. was recorded from each locality. Samples from Common carp were identified as the invasive A. japonicus, and samples from Pike-perch and Brook trout were identified as A. foliaceus. Evidence of a mixed infection of Pike-perch with both A. foliaceus and A. japonicus was found in samples from Zemplínska Šírava, which was substantiated by electron microscopic examination. Morphometric characteristics were measured and averages and ranges produced for each species and sex.

  7. Fish parasites

    DEFF Research Database (Denmark)

    This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems......This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems...

  8. Fish pelleting

    African Journals Online (AJOL)

    PUBLICATIONS1

    fish meal pelletizing machine utilized 4kg of ingredients to produce 3.77kg pellets at an effi- ciency of .... Design and fabrication of fish meal pellet processing machine ... 53 ... horsepower for effective torque application on .... two edges were tacked with a spot weld to hold ... then welded on to the shaft making sure that the.

  9. [Performance evaluation of a fluorescamine-HPLC method for determination of histamine in fish and fish products].

    Science.gov (United States)

    Kikuchi, Hiroyuki; Tsutsumi, Tomoaki; Matsuda, Rieko

    2012-01-01

    A method for the quantification of histamine in fish and fish products using tandem solid-phase extraction and fluorescence derivatization with fluorescamine was previously developed. In this study, we improved this analytical method to develop an official test method for quantification of histamine in fish and fish products, and performed a single laboratory study to validate it. Recovery tests of histamine from fillet (Thunnus obesus), and two fish products (fish sauce and salted and dried whole big-eye sardine) that were spiked at the level of 25 and 50 µg/g for T. obesus, and 50 and 100 µg/g for the two fish products, were carried out. The recoveries of histamine from the three samples tested were 88.8-99.6% with good repeatability (1.3-2.1%) and reproducibility (2.1-4.7%). Therefore, this method is acceptable for the quantification of histamine in fish and fish products. Moreover, surveillance of histamine content in food on the market was conducted using this method, and high levels of histamine were detected in some fish products.

  10. Test results on vegetable cultivation using fish breeding water; Yogyosui riyo ni yoru yasai saibai shikenkekka ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Nishida, S. [Hokuriku Electric Power Co. Inc., Toyama (Japan)

    1997-10-30

    Although a part of the entrails of fishes, birds and livestock is used for food, most of them are treated by costly combustion because of their bad odor and looking, and International Environment and Welfare Laboratory, Toyama prefecture in Japan is studying their profitable treatment. As a part of such study, possibility of hydroponic cultivation of vegetable was tested using fish breeding water including excretions of fishes and residual feeds after use of waste as feed, and the growth condition, safety and effectiveness of cultured vegetable were verified. Three-hundred and fifty viviparous Oryzias were released into a breeding water area with no controlled pH and EC (electric conductivity). For comparison a culture solution area of 6.0 in pH and 1.2ms/cm in EC was prepared. The result on cultivation of 6 kinds of vegetable in culture beds supported by circulation of these water showed that hydroponic cultivation of vegetable using fish breeding water is possible, and average growth of 68% is obtained although difference in growth for every vegetable is found. 8 figs., 5 tabs.

  11. Fish population dynamics

    National Research Council Canada - National Science Library

    Gulland, J. A

    1977-01-01

    This book describes how the dynamics of fish populations can be analysed in terms of the factors affecting their rates of growth, mortality and reproduction, with particular emphasis on the effects of fishing...

  12. Grande Ronde Basin Fish Habitat Enhancement Project : 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Vance R.; Powell, Russ M.; Stennfeld, Scott P.

    2001-04-01

    On July 1, 1984 the Bonneville Power Administration and the Oregon Department of Fish and Wildlife entered into an agreement to initiate fish habitat enhancement work in the Joseph Creek subbasin of the Grande Ronde River Basin in northeast Oregon. In July of 1985 the Upper and Middle Grande Ronde River, and Catherine Creek subbasins were included in the intergovernmental contract, and on March 1, 1996 the Wallowa River subbasin was added. The primary goal of ''The Grande Ronde Basin Fish Habitat Enhancement Project'' is to access, create, improve, protect, and restore riparian and instream habitat for anadromous salmonids, thereby maximizing opportunities for natural fish production within the basin. This project provided for implementation of Program Measure 703 (C)(1), Action Item 4.2 of the Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program (NPPC, 1987), and continues to be implemented as offsite mitigation for mainstem fishery losses caused by the Columbia River hydro-electric system. All work conducted by the Oregon Department of Fish and Wildlife is on private lands and therefore requires that considerable time be spent developing rapport with landowners to gain acceptance of, and continued cooperation with this program throughout 10-15 year lease periods. This project calls for passive regeneration of habitat, using riparian enclosure fencing as the primary method to restore degraded streams to a normative condition. Active remediation techniques using plantings, off-site water developments, site-specific instream structures, or whole channel alterations are also utilized where applicable. Individual projects contribute to and complement ecosystem and basin-wide watershed restoration efforts that are underway by state, federal, and tribal agencies, and local watershed councils. Work undertaken during 2000 included: (1) Implementing 2 new projects in the Grande Ronde drainage, and retrofitting one old

  13. Histamine fish poisoning revisited.

    Science.gov (United States)

    Lehane, L; Olley, J

    2000-06-30

    Histamine (or scombroid) fish poisoning (HFP) is reviewed in a risk-assessment framework in an attempt to arrive at an informed characterisation of risk. Histamine is the main toxin involved in HFP, but the disease is not uncomplicated histamine poisoning. Although it is generally associated with high levels of histamine (> or =50 mg/100 g) in bacterially contaminated fish of particular species, the pathogenesis of HFP has not been clearly elucidated. Various hypotheses have been put forward to explain why histamine consumed in spoiled fish is more toxic than pure histamine taken orally, but none has proved totally satisfactory. Urocanic acid, like histamine, an imidazole compound derived from histidine in spoiling fish, may be the "missing factor" in HFP. cis-Urocanic acid has recently been recognised as a mast cell degranulator, and endogenous histamine from mast cell degranulation may augment the exogenous histamine consumed in spoiled fish. HFP is a mild disease, but is important in relation to food safety and international trade. Consumers are becoming more demanding, and litigation following food poisoning incidents is becoming more common. Producers, distributors and restaurants are increasingly held liable for the quality of the products they handle and sell. Many countries have set guidelines for maximum permitted levels of histamine in fish. However, histamine concentrations within a spoiled fish are extremely variable, as is the threshold toxic dose. Until the identity, levels and potency of possible potentiators and/or mast-cell-degranulating factors are elucidated, it is difficult to establish regulatory limits for histamine in foods on the basis of potential health hazard. Histidine decarboxylating bacteria produce histamine from free histidine in spoiling fish. Although some are present in the normal microbial flora of live fish, most seem to be derived from post-catching contamination on board fishing vessels, at the processing plant or in the

  14. Parvalbumin--the major tropical fish allergen.

    Science.gov (United States)

    Lim, Dawn Li-Chern; Neo, Keng Hwee; Yi, Fong Cheng; Chua, Kaw Yan; Goh, Denise Li-Meng; Shek, Lynette Pei-Chi; Giam, Yoke Chin; Van Bever, Hugo P S; Lee, Bee Wah

    2008-08-01

    Fish allergy is common in countries where consumption is high. Asian nations are amongst the world's largest consumers of fish but the allergen profiles of tropical fish are unknown. This study sought to evaluate the allergenicity of four commonly consumed tropical fish, the threadfin (Polynemus indicus), Indian anchovy (Stolephorus indicus), pomfret (Pampus chinensis) and tengirri (Scomberomorus guttatus). Immunoglobulin E (IgE) cross-reactivity with parvalbumin of cod fish (Gad c 1), the major fish allergen, was also studied. Detection of tropical fish and cod specific-IgE was performed by UniCap assay, and skin prick tests were also carried out. The IgE-binding components of tropical fish were identified using IgE immunoblot techniques, and cross-reactivity with Gad c 1 was assessed by ELISA inhibition and IgE immunoblot inhibition. Clinically, nine of 10 patients studied were allergic to multiple fish. All patients exhibited detectable specific-IgE to cod fish (10 of 10 skin prick test positive, eight of 10 UniCap assay positive) despite lack of previous exposure. The major allergen of the four tropical fish was the 12-kDa parvalbumin. IgE cross-reactivity of these allergens to Gad c 1 was observed to be moderate to high in the tropical fish studied. Parvalbumins are the major allergens in commonly consumed tropical fish. They are cross-reactive with each other as well as with Gad c 1. Commercial tests for cod fish appear to be sufficient for the detection of tropical fish specific-IgE.

  15. Distance from a fishing community explains fish abundance in a no-take zone with weak compliance.

    Directory of Open Access Journals (Sweden)

    Sahir Advani

    Full Text Available There are numerous examples of no-take marine reserves effectively conserving fish stocks within their boundaries. However, no-take reserves can be rendered ineffective and turned into 'paper parks' through poor compliance and weak enforcement of reserve regulations. Long-term monitoring is thus essential to assess the effectiveness of marine reserves in meeting conservation and management objectives. This study documents the present state of the 15-year old no-take zone (NTZ of South El Ghargana within the Nabq Managed Resource Protected Area, South Sinai, Egyptian Red Sea. Previous studies credited willing compliance by the local fishing community for the increased abundances of targeted fish within the designated NTZ boundaries compared to adjacent fished or take-zones. We compared benthic habitat and fish abundance within the NTZ and the adjacent take sites open to fishing, but found no significant effect of the reserve. Instead, the strongest evidence was for a simple negative relationship between fishing pressure and distance from the closest fishing village. The abundance of targeted piscivorous fish increased significantly with increasing distance from the village, while herbivorous fish showed the opposite trend. This gradient was supported by a corresponding negative correlation between the amount of discarded fishing gear observed on the reef and increasing distance from the village. Discarded fishing gear within the NTZ suggested decreased compliance with the no-take regulations. Our findings indicate that due to non-compliance the no-take reserve is no longer functioning effectively, despite its apparent initial successes and instead a gradient of fishing pressure exists with distance from the nearest fishing community.

  16. Consumers’ attitude towards fish meat

    Directory of Open Access Journals (Sweden)

    Francesca Conte

    2014-09-01

    Full Text Available The overall aim of this paper is to show the factors that may affect consumers’ attitude towards farmed fish products. Consumers ask new products on the basis of different quality attributes: stability, safety, composition, better health effects, environment protection, etc. Different and controversial opinions on farmed and wild fish are also explored by literature review. The authors pay attention also to fish welfare as an emerging issue and effective information about fish products as a factor exerting a positive influence on consumers’ decision of purchase. Some relevant legislative notes on the paper’s topics are also cited. The qualitative aspects of aquaculture fish and the consumers’ demand and choice need further studies, according to some factors, such as the changing consumers’ attitudes towards fish products, the different fish quality perception and the development in the aquaculture systems.

  17. Comparative effect of pesticides on brain acetylcholinesterase in tropical fish.

    Science.gov (United States)

    Assis, Caio Rodrigo Dias; Linhares, Amanda Guedes; Oliveira, Vagne Melo; França, Renata Cristina Penha; Carvalho, Elba Veronica Matoso Maciel; Bezerra, Ranilson Souza; de Carvalho, Luiz Bezerra

    2012-12-15

    Monitoring of pesticides based on acetylcholinesterase (AChE; EC 3.1.1.7) inhibition in vitro avoids interference of detoxification defenses and bioactivation of some of those compounds in non-target tissues. Moreover, environmental temperature, age and stress are able to affect specific enzyme activities when performing in vivo studies. Few comparative studies have investigated the inter-specific differences in AChE activity in fish. Screening studies allow choosing the suitable species as source of AChE to detect pesticides in a given situation. Brain AChE from the tropical fish: pirarucu (Arapaima gigas), cobia (Rachycentron canadum) and Nile tilapia (Oreochromis niloticus) were characterized and their activities were assayed in the presence of pesticides (the organophosphates: dichlorvos, diazinon, chlorpyrifos, temephos, tetraethyl pyrophosphate- TEPP and the carbamates: carbaryl and carbofuran). Inhibition parameters (IC₅₀ and Ki) for each species were found and compared with commercial AChE from electric eel (Electrophorus electricus). Optimal pH and temperature were found to be 8.0 and 35-45 °C, respectively. A. gigas AChE retained 81% of the activity after incubation at 50 °C for 30 min. The electric eel enzyme was more sensitive to the compounds (mainly carbofuran, IC₅₀ of 5 nM), excepting the one from A. gigas (IC₅₀ of 9 nM) under TEPP inhibition. These results show comparable sensitivity between purified and non-purified enzymes suggesting them as biomarkers for organophosphorus and carbamate detection in routine environmental and food monitoring programs for pesticides. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Contamination with heavy metals and bacteria in some local and imported fish and fish products

    International Nuclear Information System (INIS)

    Salem, S.B.; El-Dashlout, A.A.; El-Schiwee, M.A.; EL-Shourbagy, G.A.; Ibrahim, R.E.

    2004-01-01

    Some local and imported fish and fish products sold in retail markets of three cities at Sharkia Governorate, Egypt, were examined against heavy metals contamination (i.e. Pb, Cd and Hg) and the presence of some specific groups of bacteria. The results showed that concentrations of Pb in fresh and frozen fish, salted and smoked fish and canned fish samples were lower than the permissible limits recommended by the Egyptian Organization 1993 (1.0 mg/kg). On the other hand, all the tested fish and fish products of collected samples showed levels of Cd (0.29-0.41 mg/kg) higher than the permissible limit (0.10 mg/kg) recommended by the Egyptian Organization. Such limits should be re-considered because the limit determined by WHO (1992) was 0.5 mg/kg. Mercury level in fresh mullet was equal or lower (0.46-0.50 mg/kg) than the limit of Egyptian Organization (0.50 mg/kg) while other fresh and frozen fish, salted and smoked fish samples had higher Hg than the allowance. In most cases, imported canned products of sardine, mackerel and tuna had higher Pb, Cd and Hg concentrations than that found in the local ones. Among fresh fish samples, such as mackarona, contained the highest total bacterial count, while mullet was the lowest. Considering salted and smoked fish, heavy salted mullet had the highest total bacterial count, while the lowest number was recorded in salted sardine. Smoked herring showed lowest total bacterial count than salted samples. Generally, no correlation was observed between fish species or consumption place and the contamination with heavy metals and bacteria

  19. [Imported tropical fish causes ciguatera fish poisoning in Germany].

    Science.gov (United States)

    Zimmermann, Katharina; Eisenblätter, Anneka; Vetter, Irina; Ebbecke, Martin; Friedemann, Miriam; Desel, Herbert

    2015-01-01

    Ciguatera is a seafood-borne illness caused by consumption of tropical fish contaminated with ciguatoxins, lipophilic polyethers that are produced in benthic dinoflagellates and accumulate through the marine food chain. Ciguatera cases in Europe usually occur in travellers returning from tropical and subtropical regions of the Pacific and Carribean, where ciguatera is endemic. In 2012, several cases of ciguatera occurred in Germany due to sale of contaminated fish products originating from the Indian Ocean. Although the symptomatology in these cases were typical of ciguatera, with patients reporting gastrointestinal discomfort including nausea, vomiting and diarrhea as well as neurological effects including widespread intense pruritus, paresthesias, hypothermia or altered temperature sensation and diffuse pain, correct diagnosis was delayed in all cases due to lack of awareness of the treating medical practitioners. In light of increasing global mobility, trade, and occurrence of ciguatoxic fish in previously non-endemic areas, ciguatera should be considered as a possible diagnosis if gastrointestinal and neurological symptoms occur shortly after consumption of fish. Georg Thieme Verlag Stuttgart.

  20. Fish-friendly future

    International Nuclear Information System (INIS)

    Brookshier, P.; Newman, Gemma

    2001-01-01

    The latest US research into ways of reducing the harm to fish from hydroelectric turbines is outlined. Laboratory studies, field studies and advanced computational studies are being carried out to improve the understanding of and reduce the effects of stress and injury to fish from turbines. The Advanced Hydro Turbine System programme is part of the Department of Energy's Hydropower Programme. Turbine passage injuries are caused by a number of mechanisms, leaving the fish either dead or stunned. Advanced turbine technology can help to minimise fish injury and can add dissolved oxygen to the discharged water, thus improving water quality. Turbine modifications are aimed at all species, but studies have focussed on salmon, trout and eels. The new minimum gap runner (MGR) appear as efficient as standard Kaplan turbines

  1. Of Fish and Micrornas

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    Fish is an important small vertebrate multidisciplinary model for investigating various aspects of reproduction, development, disease (immunology, toxicology, carcinogenesis), and aging. It is also an important model for comparative and evolutionary studies because it represents the lower...... to the mechanisms of control of gene expression, impacting a broad range of biological processes. Thus far, >25, 000 miRNA sequences have been identified in 193 species, including fish. In fish, the interest on miRNAs started with the analysis of their expression and function during embryonic development. In our...... selection markers to identify disease-resistant fish....

  2. Changes in the North Sea fish community: evidence of indirect effects of fishing?

    NARCIS (Netherlands)

    Daan, N.; Gislason, H.; Pope, J.G.; Rice, J.C.

    2005-01-01

    We investigate changes in the North Sea fish community with particular reference to possible indirect effects of fishing, mediated through the ecosystem. In the past, long-term changes in the slope of size spectra of research vessel catches have been related to changes in fishing effort, but such

  3. A review on robotic fish enabled by ionic polymer-metal composite artificial muscles.

    Science.gov (United States)

    Chen, Zheng

    2017-01-01

    A novel actuating material, which is lightweight, soft, and capable of generating large flapping motion under electrical stimuli, is highly desirable to build energy-efficient and maneuverable bio-inspired underwater robots. Ionic polymer-metal composites are important category of electroactive polymers, since they can generate large bending motions under low actuation voltages. IPMCs are ideal artificial muscles for small-scale and bio-inspired robots. This paper takes a system perspective to review the recent work on IPMC-enabled underwater robots, from modeling, fabrication, and bio-inspired design perspectives. First, a physics-based and control-oriented model of IPMC actuator will be reviewed. Second, a bio-inspired robotic fish propelled by IPMC caudal fin will be presented and a steady-state speed model of the fish will be demonstrated. Third, a novel fabrication process for 3D actuating membrane will be introduced and a bio-inspired robotic manta ray propelled by two IPMC pectoral fins will be demonstrated. Fourth, a 2D maneuverable robotic fish propelled by multiple IPMC fin will be presented. Last, advantages and challenges of using IPMC artificial muscles in bio-inspired robots will be concluded.

  4. Activation of Pax7-positive cells in a non-contractile tissue contributes to regeneration of myogenic tissues in the electric fish S. macrurus.

    Directory of Open Access Journals (Sweden)

    Christopher M Weber

    Full Text Available The ability to regenerate tissues is shared across many metazoan taxa, yet the type and extent to which multiple cellular mechanisms come into play can differ across species. For example, urodele amphibians can completely regenerate all lost tissues, including skeletal muscles after limb amputation. This remarkable ability of urodeles to restore entire limbs has been largely linked to a dedifferentiation-dependent mechanism of regeneration. However, whether cell dedifferentiation is the fundamental factor that triggers a robust regeneration capacity, and whether the loss or inhibition of this process explains the limited regeneration potential in other vertebrates is not known. Here, we studied the cellular mechanisms underlying the repetitive regeneration of myogenic tissues in the electric fish S. macrurus. Our in vivo microinjection studies of high molecular weight cell lineage tracers into single identified adult myogenic cells (muscle or noncontractile muscle-derived electrocytes revealed no fragmentation or cellularization proximal to the amputation plane. In contrast, ultrastructural and immunolabeling studies verified the presence of myogenic stem cells that express the satellite cell marker Pax7 in mature muscle fibers and electrocytes of S. macrurus. These data provide the first example of Pax-7 positive muscle stem cells localized within a non-contractile electrogenic tissue. Moreover, upon amputation, Pax-7 positive cells underwent a robust replication and were detected exclusively in regions that give rise to myogenic cells and dorsal spinal cord components revealing a regeneration process in S. macrurus that is dependent on the activation of myogenic stem cells for the renewal of both skeletal muscle and the muscle-derived electric organ. These data are consistent with the emergent concept in vertebrate regeneration that different tissues provide a distinct progenitor cell population to the regeneration blastema, and these

  5. Farming in a fish tank.

    Science.gov (United States)

    Youth, H

    1992-01-01

    Water, fish, and vegetables are all things that most developing countries do not have enough of. There is a method of food production called aquaculture that integrates fish and vegetable growing and conserves and purifies water at the same time. A working system that grows vegetables and fish for regional supermarkets in Massachusetts is a gravity fed system. At the top of the system is a 3,000 gallon fish rearing tank that measures 12 feet in diameter. Water trickles out of the tank and fish wastes are captured which can be composted and used in farm fields. The water goes into a bio filter that contains bacteria which convert harmful ammonia generated from fish waste into beneficial nitrate. Then the water flows into 100 foot long hydroponic tanks where lettuce grows. A 1/6 horsepower pump return the purified water to the fish tank and completes the cycle. The key to success is maintaining a balance between the fish nutrients and waste and the plants nutrients and waste. The system is estimated to produce 35,000 heads of lettuce and 2 tons of fish annually which translates into $23,500. The system could be adapted to developing countries with several modifications to reduce the start up cost.

  6. A survey of dioxin-like contaminants in fish from recreational fishing.

    Science.gov (United States)

    Heimstad, Eldbjørg Sofie; Grønstøl, Gaute; Hetland, Karl Torstein; Alarcon, Javier Martinez; Rylander, Charlotta; Mariussen, Espen

    2015-08-01

    The dioxin and dioxin-like compounds are regarded as one of the most toxic group of environmental contaminants. Food for the commercial market is regularly monitored for their dioxin levels and the concentration allowed in food is strictly regulated. Less is known about locally caught fish from recreational fishing, which is often brought home for consumption. This can be fish caught from nearby lakes or streams or fish with marine origin close to industrial areas or harbours that are not regularly monitored for their dioxin levels. In this study, we established collaboration with schools in 13 countries. We received 203 samples of 29 different fish species of which Atlantic cod was the most abundant followed by brown trout and pollock. In general, the majority of samples from the participating countries had low concentrations (between 0.1 and 0.2 pg/g chemical-activated luciferase gene expression toxic equivalency wet weight (CALUX TEQ w.w.)) of dioxins and dioxin-like PCBs. Only 18 samples had concentrations above 1 pg/g CALUX TEQ w.w., and only 2 dab samples had concentration above maximum levels set by the European Commission. The Atlantic cod samples showed a significant reduction in the concentrations of dioxins with increasing latitude indicating less contamination of dioxin and dioxin-like compounds in the north of Norway. The results indicate that a moderate consumption of self-caught fish at presumed non-contaminated sites does not represent a major risk for exposure to dioxins or dioxin-like compounds at concentrations associated with adverse health effects. Recreational fishermen should, however, obtain knowledge about local fish consumption advice.

  7. DEVELOPMENT OF TECHNOLOGY FOR FISH CANNED PATE'S COD-FISH SPECIES

    Directory of Open Access Journals (Sweden)

    A. A. Efremova

    2014-01-01

    Full Text Available Summary. Fish and seafood play an important role in a balanced diet. The most reliable method of preservation is the production of canned fish. Cod fishery considered traditional objects of the North Basin, which catches in recent years stored at a consistently high level. They are represented, mainly cod, haddock, pollack, whiting. Lately there has been a tendency to increase yield loaves (polar bib. The aim of this work - the development of technology - canned pate's cod fish species with the addition of plant materials. We used the adopted research microbiological, chemical and physical methods. The weight proportion of water, lipids, protein, mineral raw determined according to State standard 7636-85. Developed a technology - canned pate's cod fish species with the addition of plant materials. Optimized formulation is set to sterilization. Experimentally determined parameters of quality canned and given comprehensive assessment nutritional value of new products, organoleptic, physico-chemical, biochemical and microbiological tests showed that canned pates of Gadidae species of fish with vegetables, meet all safety requirements and are characterized, along with excellent consumer properties, high nutritional value. Based on the results of the research complex developed technical documentation for production of canned vegetables, pates of Gadidae species.

  8. Why do fish school?

    Institute of Scientific and Technical Information of China (English)

    Matz LARSSON

    2012-01-01

    Synchronized movements (schooling) emit complex and overlapping sound and pressure curves that might confuse the inner ear and lateral line organ (LLO) of a predator.Moreover,prey-fish moving close to each other may blur the electro-sensory perception of predators.The aim of this review is to explore mechanisms associated with synchronous swimming that may have contributed to increased adaptation and as a consequence may have influenced the evolution of schooling.The evolutionary development of the inner ear and the LLO increased the capacity to detect potential prey,possibly leading to an increased potential for cannibalism in the shoal,but also helped small fish to avoid joining larger fish,resulting in size homogeneity and,accordingly,an increased capacity for moving in synchrony.Water-movements and incidental sound produced as by-product of locomotion (ISOL) may provide fish with potentially useful information during swimming,such as neighbour body-size,speed,and location.When many fish move close to one another ISOL will be energetic and complex.Quiet intervals will be few.Fish moving in synchrony will have the capacity to discontinue movements simultaneously,providing relatively quiet intervals to allow the reception of potentially critical environmental signals.Besides,synchronized movements may facilitate auditory grouping of ISOL.Turning preference bias,well-functioning sense organs,good health,and skillful motor performance might be important to achieving an appropriate distance to school neighbors und aid the individual fish in reducing time spent in the comparatively less safe school periphery.Turning preferences in ancestral fish shoals might have helped fish to maintain groups and stay in formarion,reinforcing aforementioned predator confusion mechanisms,which possibly played a role in the lateralization of the vertebrate brain [Current Zoology 58 (1):116-128,2012].

  9. 50 CFR 404.10 - Commercial fishing.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Commercial fishing. 404.10 Section 404.10... MARINE NATIONAL MONUMENT § 404.10 Commercial fishing. (a) Lobster fishing. Any commercial lobster fishing... species. (1) Notwithstanding the prohibitions in § 404.7(a) and (h), commercial fishing for bottomfish and...

  10. Guidelines for risk-based fish inspection

    OpenAIRE

    2015-01-01

    Fish and fishery products are nutritious and healthy and are an important source of food and livelihood for many millions of people worldwide. Fish inspection is concerned with ensuring that the consumer has access to safe and nutritious fish and fish products, whether the fish is from domestic sources of supply, imported or to be exported to consumers in another country. The present guidelines will assist fish inspectors to carry out these responsibilities--Publisher's description.

  11. Trace elements in two marine fish cultured in fish cages in Fujian province, China

    International Nuclear Information System (INIS)

    Onsanit, Sarayut; Ke Caihuan; Wang Xinhong; Wang Kejian; Wang Wenxiong

    2010-01-01

    Two cultured marine fish, the Japanese seabass (Lateolabrax japonicus) and red seabream (Pagrus major) were collected from eight fish cage sites along the coast of Fujian province in China. The concentrations of Ag, As, Cd, Co, Cu, Fe, Mn, Se, and Zn in their muscle, stomach and liver tissue were quantified. The risk of these trace elements to humans through fish consumption was then assessed. The highest concentrations of As, Cd, Se and Zn in fish feed from fish cages were found in Dongshan Station. Moreover, the As levels in the muscles of both species at all sites were generally higher than China's national standard (>1.0 μg/g). Trace element concentrations in two marine fish followed the order of livers > stomachs > muscles. Although the As levels in two marine caged fish exceeded the permissible standards, the estimated daily intake of As did not exceed the reference dose guideline established by US EPA. For other trace elements examined in this study, their concentrations did not exceed the permissible concentrations of the international standards. - As levels in two marine caged fish from China exceeded the permissible standards, whereas the levels of others trace elements did not exceed the permissible concentrations.

  12. Fishing Farmers or Farming Fishers? Fishing Typology of Inland Small-Scale Fishing Households and Fisheries Management in Singkarak Lake, West Sumatra, Indonesia

    Science.gov (United States)

    Yuerlita; Perret, Sylvain Roger; Shivakoti, Ganesh P.

    2013-07-01

    Technical and socio-economic characteristics are known to determine different types of fishers and their livelihood strategies. Faced with declining fish and water resources, small-scale fisheries engage into transformations in livelihood and fishing practices. The paper is an attempt to understand these changes and their socio-economic patterns, in the case of Singkarak Lake in West Sumatra, Indonesia. Based upon the hypothesis that riparian communities have diverse, complex yet structured and dynamic livelihood systems, the paper's main objective is to study, document and model the actual diversity in livelihood, practices and performance of inland small-scale fisheries along the Singkarak Lake, to picture how households are adapted to the situation, and propose an updated, workable model (typology) of those for policy. Principal component analysis and cluster analysis were used to develop a typology of fishing households. The results show that small-scale fishers can be classified into different types characterized by distinct livelihood strategies. Three household types are identified, namely "farming fishers" households (type I, 30 %), "fishing farmers" households (type II, 30 %), and "mainly fishers" households (type III, 40 %). There are significant differences among these groups in the number of boats owned, annual fishing income, agriculture income and farming experience. Type I consists of farming fishers, well equipped, with high fishing costs and income, yet with the lowest return on fishing assets. They are also landowners with farming income, showing the lowest return on land capital. Type II includes poor fishing farmers, landowners with higher farming income; they show the highest return on land asset. They have less fishing equipment, costs and income. Type III (mainly fishers) consists of poorer, younger fishers, with highest return on fishing assets and on fishing costs. They have little land, low farming income, and diversified livelihood

  13. The fishes of Genome 10K

    KAUST Repository

    Bernardi, Giacomo

    2012-09-01

    The Genome 10K project aims to sequence the genomes of 10,000 vertebrates, representing approximately one genome for each vertebrate genus. Since fishes (cartilaginous fishes, ray-finned fishes and lobe-finned fishes) represent more than 50% of extant vertebrates, it is planned to target 4,000 fish genomes. At present, nearly 60 fish genomes are being sequenced at various public funded labs, and under a Genome 10K and BGI pilot project. An additional 100 fishes have been identified for sequencing in the next phase of Genome 10K project. © 2012 Elsevier B.V.

  14. The fishes of Genome 10K

    KAUST Repository

    Bernardi, Giacomo; Wiley, Edward O.; Mansour, Hicham; Miller, Michael R.; Ortí , Guillermo; Haussler, David H.; O'Brien, Stephen J O; Ryder, Oliver A.; Venkatesh, Byrappa

    2012-01-01

    The Genome 10K project aims to sequence the genomes of 10,000 vertebrates, representing approximately one genome for each vertebrate genus. Since fishes (cartilaginous fishes, ray-finned fishes and lobe-finned fishes) represent more than 50% of extant vertebrates, it is planned to target 4,000 fish genomes. At present, nearly 60 fish genomes are being sequenced at various public funded labs, and under a Genome 10K and BGI pilot project. An additional 100 fishes have been identified for sequencing in the next phase of Genome 10K project. © 2012 Elsevier B.V.

  15. Conditions for instant electrical stunning of farmed Atlantic cod after de-watering, maintenance of unconsciousness, effects of stress, and fillet quality — A comparison with AQUI-S™

    NARCIS (Netherlands)

    Erikson, U.; Lambooij, E.; Digre, H.; Reimert, H.G.M.; Bondø, M.; Vis, van de H.

    2012-01-01

    Electrical stunning of farmed Atlantic cod is a method used to render the fish unconscious before further processing. However, evaluations of the stunning method at plants have shown that the electrical parameters need to be optimized to achieve instant stunning and prolonged duration of

  16. Freshwater and fish

    International Nuclear Information System (INIS)

    Saxen, R.

    1997-01-01

    Severe radioactive contamination of the freshwater environment could have serious consequences for both drinking water and fish. Most of the Nordic countries have an abundance of freshwater lakes and rivers. Finland alone has about 56,000 lakes, each with a surface area of 1 hectare or more. Nearly 10% of Finland's surface is covered with lakes and rivers. In Sweden, about 9% of the surface area is freshwater, in Norway about 5%, and in Denmark only about 2%. Freshwater plays a minor role in Iceland, but even there numerous rivers discharge from the volcanic soils to the Ocean. Cs-137 and 90 Sr are likely to be the most important radionuclides with respect to long term radioactive contamination of freshwater. If radioactive deposition occurs in the absence of snow and ice radionuclides will contaminate the surface water directly and may rapidly enter the aquatic food chain. Fish which eat contaminated plankton become contaminated almost immediately. Deposition during summer increases the transfer for radionuclides to fish since fish metabolism is faster during the warm season. During the cold period, fish metabolism is slow and thus uptake and excretion of radiocaesium are also slow. (EG)

  17. Maryland ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Maryland. Vector polygons in this data...

  18. Virginia ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and brackishwater fish species in Virginia. Vector polygons in this data...

  19. Louisiana ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for freshwater (inland) fish species in coastal Louisiana. Vector polygons represent water-bodies and other...

  20. Effects of human population density and proximity to markets on coral reef fishes vulnerable to extinction by fishing.

    Science.gov (United States)

    Brewer, T D; Cinner, J E; Green, A; Pressey, R L

    2013-06-01

    Coral reef fisheries are crucial to the livelihoods of tens of millions of people; yet, widespread habitat degradation and unsustainable fishing are causing severe depletion of stocks of reef fish. Understanding how social and economic factors, such as human population density, access to external markets, and modernization interact with fishing and habitat degradation to affect fish stocks is vital to sustainable management of coral reef fisheries. We used fish survey data, national social and economic data, and path analyses to assess whether these factors explain variation in biomass of coral reef fishes among 25 sites in Solomon Islands. We categorized fishes into 3 groups on the basis of life-history characteristics associated with vulnerability to extinction by fishing (high, medium, and low vulnerability). The biomass of fish with low vulnerability was positively related to habitat condition. The biomass of fishes with high vulnerability was negatively related to fishing conducted with efficient gear. Use of efficient gear, in turn, was strongly and positively related to both population density and market proximity. This result suggests local population pressure and external markets have additive negative effects on vulnerable reef fish. Biomass of the fish of medium vulnerability was not explained by fishing intensity or habitat condition, which suggests these species may be relatively resilient to both habitat degradation and fishing. © 2012 Society for Conservation Biology.

  1. Survey of n-3 and n-6 polyunsaturated fatty acids in fish and fish products.

    Science.gov (United States)

    Strobel, Claudia; Jahreis, Gerhard; Kuhnt, Katrin

    2012-10-30

    The imbalance of the n-3/n-6 ratio in the Western diet is characterised by a low intake of n-3 long-chain (LC) PUFA and a concurrent high intake of n-6 PUFA. Fish, in particular marine fish, is a unique source of n-3 LC PUFA. However, FA composition of consumed fish changed, due to the increasing usage of n-6 PUFA-rich vegetable oils in aquaculture feed and in fish processing (frying) which both lead to a further shift in n-6 PUFA to the detriment of n-3 LC PUFA.The aim of this study was to determine the ratio of n-3/n-6 including the contents of EPA and DHA in fish fillets and fish products from the German market (n=123). Furthermore, the study focussed on the FA content in farmed salmon compared to wild salmon as well as in processed Alaska pollock fillet, e.g., fish fingers. Total fat and FA content in fish products varied considerably depending on fish species, feed management, and food processing. Mackerel, herring and trout fillets characteristically contained adequate dietary amounts of absolute EPA and DHA, due to their high fat contents. However, despite a lower fat content, tuna, pollock, and Alaska pollock can contribute considerable amounts of EPA and DHA to the human supply.Farmed salmon are an appropriate source of EPA and DHA owing to their higher fat content compared to wild salmon (12.3 vs. 2.1 wt %), however with elevated SFA, n-9 and n-6 FA contents representing the use of vegetable oils and oilseeds in aquaculture feed. The n-3/n-6 ratio was deteriorated (2.9 vs. 12.4) but still acceptable. Compared to pure fish fillets, breaded and pre-fried Alaska pollock fillet contained extraordinarily high fat and n-6 PUFA levels. Since fish species vary with respect to their n-3 LC PUFA contents, eating a variety of fish is advisable. High n-6 PUFA containing pre-fried fish support the imbalance of n-3/n-6 ratio in the Western diet. Thus, consumption of pure fish fillets is to be favoured. The lower n-3 PUFA portion in farmed fish can be offset by the

  2. Survey of n-3 and n-6 polyunsaturated fatty acids in fish and fish products

    Directory of Open Access Journals (Sweden)

    Strobel Claudia

    2012-10-01

    Full Text Available Abstract Background The imbalance of the n-3/n-6 ratio in the Western diet is characterised by a low intake of n-3 long-chain (LC PUFA and a concurrent high intake of n-6 PUFA. Fish, in particular marine fish, is a unique source of n-3 LC PUFA. However, FA composition of consumed fish changed, due to the increasing usage of n-6 PUFA-rich vegetable oils in aquaculture feed and in fish processing (frying which both lead to a further shift in n-6 PUFA to the detriment of n-3 LC PUFA. The aim of this study was to determine the ratio of n-3/n-6 including the contents of EPA and DHA in fish fillets and fish products from the German market (n=123. Furthermore, the study focussed on the FA content in farmed salmon compared to wild salmon as well as in processed Alaska pollock fillet, e.g., fish fingers. Results Total fat and FA content in fish products varied considerably depending on fish species, feed management, and food processing. Mackerel, herring and trout fillets characteristically contained adequate dietary amounts of absolute EPA and DHA, due to their high fat contents. However, despite a lower fat content, tuna, pollock, and Alaska pollock can contribute considerable amounts of EPA and DHA to the human supply. Farmed salmon are an appropriate source of EPA and DHA owing to their higher fat content compared to wild salmon (12.3 vs. 2.1 wt %, however with elevated SFA, n-9 and n-6 FA contents representing the use of vegetable oils and oilseeds in aquaculture feed. The n-3/n-6 ratio was deteriorated (2.9 vs. 12.4 but still acceptable. Compared to pure fish fillets, breaded and pre-fried Alaska pollock fillet contained extraordinarily high fat and n-6 PUFA levels. Conclusions Since fish species vary with respect to their n-3 LC PUFA contents, eating a variety of fish is advisable. High n-6 PUFA containing pre-fried fish support the imbalance of n-3/n-6 ratio in the Western diet. Thus, consumption of pure fish fillets is to be favoured. The lower

  3. Consumption patterns and why people fish

    International Nuclear Information System (INIS)

    Burger, Joanna

    2002-01-01

    Recreational and subsistence fishing play major roles in the lives of any people, although their importance in urban areas is often underestimated. There are fish and shellfish consumption advisories in the new York-New Jersey harbor estuary, particularly in the waters of the Newark Bay Complex. This paper examines fishing behavior, consumption patterns, and the reasons that people fish in the Newark Bay Complex. I test the null hypotheses that there are no differences among Asians, Blacks, Hispanics, and whites in consumption patterns for fish and crabs and in the reasons that they fish or crab. Most people either fished or crabbed, but not both. People who fish and crab ate more grams of crab than fish in a given meal; people who crab only consumed more grams of crab at a meal than those who fish only consumed of fish. Although 30% or more of the people who fished and crabbed in the Newark Bay Complex did not eat their self-caught fish or crabs 8-25% of the people ate more than 1500 g/month. Some people angling in the Newark Bay Complex are eating crabs at a rate well over 1500 g/month, and about 70% are eating crabs even though there is a total ban on both harvest and consumption because of the health risks from dioxin. Consumption patterns were negatively correlated with mean income and positively correlated with mean age. Most people rated relaxation and being outdoors the highest reasons or angling, although on an open-ended question they usually listed recreation. There were no ethnic differences in reasons for angling, although other studies have shown ethnic differences in consumption. Obtaining fish or crabs to eat, give away, trade, or sell were rated low, suggesting that consumption advisories fail partly because people are not primarily fishing or food

  4. Discovering the African freshwater "torpedo": legendary Ethiopia, religious controversies, and a catfish capable of reanimating dead fish.

    Science.gov (United States)

    Piccolino, Marco; Finger, Stanley; Barbara, Jean-Gaël

    2011-07-01

    The electric catfishes of African rivers and lakes, once depicted on Egyptian tomb art, have been largely overlooked in histories and reviews of electric fish biology and animal electricity. This article examines how Westerners, especially Dominican and Jesuit missionaries, discovered them in Ethiopia and other parts of Africa at the beginning of the seventeenth century. What transpired took place against the backdrop of tales involving the Bible, Prester John's mythical empire, and imaginary animals with fabulous powers. In effect, how they were found is related to attempts to convert Ethiopian Christians to true Catholicism, hopes of discovering great riches, and opportunities to trade, and not with the efforts of skilled natural philosophers to document and conduct experiments on the wildlife of this continent. Nevertheless, the early descriptions by Europeans circulated, and during the next century these catfishes began to be used in experiments that helped to make animal electricity a reality.

  5. Lipid oxidation in milk, yoghurt, and salad dressing enriched with neat fish oil or pre-emulsified fish oil

    DEFF Research Database (Denmark)

    Bruni Let, Mette; Jacobsen, Charlotte; Meyer, Anne S.

    2007-01-01

    stability than fish-oil-enriched dressings, irrespective of the mode of fish oil addition. Yoghurt thus seemed to be a good delivery system of lipids containing n-3 polyunsaturated fatty acids. Different effects of adding fish oil either as neat fish oil or as a fish-oil-in-water emulsion were observed...... of neat fish oil was a good option for preserving the final quality in yoghurt and dressings, but a pre-emulsion may still be considered for the fish oil enrichment of certain food products, for example, milk. Keywords: Fish oil; lipid oxidation; oil-in-water emulsion; n-3 PUFA; milk; yoghurt; salad......Abstract: This study compared the oxidative stabilities of fish-oil-enriched milk, yoghurt, and salad dressing and investigated the effects on oxidation of adding either neat fish oil or a fish-oil-in-water emulsion to these products. Milk emulsions had higher levels of a fishy off...

  6. Fish irradiation

    International Nuclear Information System (INIS)

    Kovacs, J.; Tengumnuay, C.; Juangbhanich, C.

    1970-01-01

    Chub-mackerel was chosen for the study because they are the most common fish in Thailand. Preliminary investigations were conducted to determine the maximum radiation dose of gamma-rays by organoleptic tests. The samples were subjected to radiation at various doses up to 4 Mrad. Many experiments were conducted using other kinds of fish. The results showed that 1 Mrad would be the maximum acceptable dose for fish. Later, the influence of the radiation dose from 0.1-1 Mrad was studied in order to find the optimum acceptable dose for preservation of fish without off-flavour. For this purpose, the Hedonic scale was used. It was found that 0.2 and 0.5 Mrad gave the best result on Chub mackerel. The determinations of optimum dose, organoleptic, microbiological and trimethylamine content changes were done. The results showed that Chub mackerel irradiated at 0.2, 0.5 and 1 Mrad stored at 3 0 C for 71 days were still acceptable, on the contrary the untreated samples were found unacceptable at 14 days. The trimethylamine increment was significantly higher in the untreated samples. At 15 days storage, trimethylamine in the non-irradiated Chub-mackerel was about 10 times higher than the irradiated ones. At 51 and 79 days storage, about 13 times higher in the control samples than the irradiated samples except 0.1 Mrad. Only 2 times higher was found for the 0.1 Mrad. The microbiological results showed that the irradiation above 0.2 Mrad gave favorable extension of shelf-life of fish

  7. Biochemical and hematological responses of the banded knife fish Gymnotus carapo (Linnaeus, 1758 exposed to environmental hypoxia

    Directory of Open Access Journals (Sweden)

    G. MORAES

    Full Text Available Oxygen of tropical freshwater environments fluctuates drastically. Eutrophic lakes and ponds of warm waters frequently reach very low oxygen concentrations. This is the most common habitat of the banded knife fish "tuvira" Gymnotus carapo. This electric fish is reported to present bimodal breathing to cope with low environmental oxygen. Biochemical responses can be also observed in fishes facing hypoxia but none were studied in tuvira. In the present study, haematological and metabolic changes were investigated in two groups of fish exposed to hypoxia for 1 and 3 hours. Haematocrit, red blood cells and haemoglobin concentration indicated erythrocyte release from hematopoietic organs and swelling of red blood cells. Glycogen, glucose, lactate, pyruvate, and amino acids were quantified in liver, kidney and white muscle. The metabolic profile of G. carapo to cope with hypoxia suggested liver gluconeogenesis probably supported by proteolysis. The kidney and liver presented the same biochemical trend suggesting similar metabolic role for both organs. Glucogenolysis followed by glucose fermentation and protein mobilisation was observed in the white muscle. The air breathing behaviour of tuvira works in parallel with metabolism to prevent damages from hypoxia. Metabolic adjustments are observed when the air taking is avoided.

  8. Biochemical and hematological responses of the banded knife fish Gymnotus carapo (Linnaeus, 1758 exposed to environmental hypoxia

    Directory of Open Access Journals (Sweden)

    MORAES G.

    2002-01-01

    Full Text Available Oxygen of tropical freshwater environments fluctuates drastically. Eutrophic lakes and ponds of warm waters frequently reach very low oxygen concentrations. This is the most common habitat of the banded knife fish "tuvira" Gymnotus carapo. This electric fish is reported to present bimodal breathing to cope with low environmental oxygen. Biochemical responses can be also observed in fishes facing hypoxia but none were studied in tuvira. In the present study, haematological and metabolic changes were investigated in two groups of fish exposed to hypoxia for 1 and 3 hours. Haematocrit, red blood cells and haemoglobin concentration indicated erythrocyte release from hematopoietic organs and swelling of red blood cells. Glycogen, glucose, lactate, pyruvate, and amino acids were quantified in liver, kidney and white muscle. The metabolic profile of G. carapo to cope with hypoxia suggested liver gluconeogenesis probably supported by proteolysis. The kidney and liver presented the same biochemical trend suggesting similar metabolic role for both organs. Glucogenolysis followed by glucose fermentation and protein mobilisation was observed in the white muscle. The air breathing behaviour of tuvira works in parallel with metabolism to prevent damages from hypoxia. Metabolic adjustments are observed when the air taking is avoided.

  9. Adirondack lakes survey: An interpretive analysis of fish communities and water chemistry, 1984--1987

    Energy Technology Data Exchange (ETDEWEB)

    Baker, J.P. (Baker (Joan P.), Raleigh, NC (USA)); Gherini, S.A.; Munson, R.K. (Tetra Tech, Inc., Pasadena, CA (USA)); Christensen, S.W. (Oak Ridge National Lab., TN (USA)); Driscoll, C.T. (Syracuse Univ., NY (USA)); Gallagher, J. (Adirondack Lakes Survey Corp., Ray Brook, NY (USA)); Newton, R.M. (Smith Coll., Northampton, MA (USA)); Reckhow, K.H. (Duke Univ., Durham, NC (USA)); Schofield, C.L. (Co

    1990-01-01

    The Adirondack Lakes Survey Corporation (ALSC) was formed as a cooperative effort of the New York State Department of Environmental Conservation and the Empire State Electric Energy Research Corporation to better characterize the chemical and biological status of Adirondack lakes. Between 1984 and 1987, the ALSC surveyed 1469 lakes within the Adirondack ecological zone. As a follow-up to the survey, the ALSC sponsored a series of interpretive analyses of the ALSC data base. The primary objectives of these analyses were as follows: Evaluate the influence of mineral acids (from acidic deposition) and nonmineral acids (natural organic acids) on lake pH levels; classify Adirondack lakes according to lake and watershed features expected to influence their responsiveness to changes in acidic deposition; evaluate the sensitivity of Adirondack lakes to changes in environmental conditions, such as changes in mineral acids or dissolved organic carbon concentrations; identify lake characteristics important in explaining the observed present-day status of fish communities in Adirondack lakes, in particular the relative importance of lake acidity; evaluate changes that have occurred over time in Adirondack fish communities and probable causes for these trends by using the available historical data on fish communities in the Adirondacks and the ALSC data base; and determine the degree to which the existing fish resource might be at risk from continued acidic deposition, or might recover if acidity levels were reduced. The basic approach examined relationships observed in the ALSC data base among watershed characteristics, lake chemistry, and fish status. Individual reports are processed separately for the data bases.

  10. Alabama ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and freshwater fish species in Alabama. Vector polygons in this data set represent...

  11. PBDE and PCB levels correlated in wild caught and farm-raised fish fillets in the USA

    Energy Technology Data Exchange (ETDEWEB)

    Hayward, D.; Wong, J.; Krynitsky, A. [US Food and Drug Administration, College Park (United States)

    2004-09-15

    Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are two classes of industrial chemicals that have been widely used in the manufacture of many materials found commonly in highly industrial societies. PCBs used as an electrical insulator and in plastics have been banned in the US since 1977. PCB levels have steadily declined in foods. PBDEs are currently used as effective flame retardant in electronics, automobiles, home furnishings, textiles and in building materials. Environmental levels have not reached equilibrium. Both classes are ubiquitous contaminants with a strong tendency for bioaccumulation. The detection of PBDEs in human and some animal fats and fish/shellfish has been reported1. Recent reports of PBDEs in the US population have reported PBDE levels higher than most other industrialized countries. The pathway of these exposures is not precisely known, but one likely pathway is food. US FDA is planning to monitor some PBDE congeners beginning 2005. Data collection will begin with fish and shellfish and most likely be expanded to other foods. Fish/shellfish are already being monitored for PCDD/F and some PCB content. Several different instrumental approaches have been used successfully to measure PBDEs in human tissues and in environmental media including HRGC/HRMS, ECNI-LRMS, EI-LRMS and tandem mass spectrometry. The focus of this study is to determine PBDE levels in fish that are already known to have higher levels of PCBs relative to other fish or other foods. EI-LRMS was selected for initial testing with PBDE measurements in fish for its simplicity and availability in every FDA field laboratory.

  12. Fishes and humankind III. Editorial.

    Directory of Open Access Journals (Sweden)

    Andrew K. G. Jones

    1999-12-01

    Full Text Available The publication of this group of three papers form part of the 1987 meeting of the International Council for Archaeozoologists Fish Remains Working Group which took place at the University of York, U. K. The papers illustrate an increased awareness of the significance of ichthyological research to archaeology and cover three areas of research: taphonomy; fishing artefacts; and fish remains recovered from an excavation. Jones sheds some light on the relative robustness of the bewildering array of elements in a fish skeleton by recording damage to a skeleton when it is trampled. His paper suggests an index of robustness which might be used to assess the degree of fragmentation in archaeological assemblages. Kemp reports on the excavation of a small medieval building located adjacent to medieval fish ponds created by Cistercian monks in North Yorkshire, England. In addition to the structural evidence, an impressive assemblage of weights, presumably net weights, found on or near the site is published. Perhaps most significant is a large lead weight which may have been used to weight catches of fish from the ponds. Fish remains recovered from two excavations at the quayside at Newcastle-upon-Tyne, England are discussed by Nicholson. Around 6000 identified bones form the basis for the study, the majority of which were identified as Gadid (cod family or herring. While the main food fishes typify fish bone assemblages from most post-Roman urban archaeological sites, the identification of small fishes such as sandeels, smelt, gobies and buttefish may indicate the utilisation of fish not nowadays considered as food at all. Given the diversity of species (30 individual species identified it is suggested that the remains from the main bone-producing organic horizons, dated to the late twelfth to thirteenth centuries, may include discard from a nearby fishmarket.

  13. In vitro evaluation of crosslinked electrospun fish gelatin scaffolds.

    Science.gov (United States)

    Gomes, S R; Rodrigues, G; Martins, G G; Henriques, C M R; Silva, J C

    2013-04-01

    Gelatin from cold water fish skin was electrospun, crosslinked and investigated as a substrate for the adhesion and proliferation of cells. Gelatin was first dissolved in either water or concentrated acetic acid and both solutions were successfully electrospun. Cross-linking was achieved via three different routes: glutaraldehyde vapor, genipin and dehydrothermal treatment. Solution's properties (surface tension, electrical conductivity and viscosity) and scaffold's properties (chemical bonds, weight loss and fiber diameters) were measured. Cellular viability was analyzed culturing 3T3 fibroblasts plated on the scaffolds and grown up to 7 days. The cells were fixed and observed with SEM or stained for DNA and F-actin and observed with confocal microscopy. In all scaffolds, the cells attached and spread with varying degrees. The evaluation of cell viability showed proliferation of cells until confluence in scaffolds crosslinked by glutaraldehyde and genipin; however the rate of growth in genipin crosslinked scaffolds was slow, recovering only by day five. The results using the dehydrothermal treatment were the less satisfactory. Our results show that glutaraldehyde treated fish gelatin is the most suitable substrate, of the three studied, for fibroblast adhesion and proliferation. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Recycle food wastes into high quality fish feeds for safe and quality fish production.

    Science.gov (United States)

    Wong, Ming-Hung; Mo, Wing-Yin; Choi, Wai-Ming; Cheng, Zhang; Man, Yu-Bon

    2016-12-01

    The amount of food waste generated from modern societies is increasing, which has imposed a tremendous pressure on its treatment and disposal. Food waste should be treated as a valuable resource rather than waste, and turning it into fish feeds would be a viable alternative. This paper attempts to review the feasibility of using food waste to formulate feed pellets to culture a few freshwater fish species, such as grass carp, grey mullet, and tilapia, under polyculture mode (growing different species in the same pond). These species occupy different ecological niches, with different feeding modes (i.e., herbivorous, filter feeding, etc.), and therefore all the nutrients derived from the food waste could be efficiently recycled within the ecosystem. The problems facing environmental pollution and fish contamination; the past and present situation of inland fish culture (focusing on South China); upgrade of food waste based feed pellets by adding enzymes, vitamin-mineral premix, probiotics (yeast), prebiotics, and Chinese medicinal herbs into feeds; and potential health risks of fish cultivated by food waste based pellets are discussed, citing some local examples. It can be concluded that appropriate portions of different types of food waste could satisfy basic nutritional requirements of lower trophic level fish species such as grass carp and tilapia. Upgrading the fish pellets by adding different supplements mentioned above could further elevated the quality of feeds, leading to higher growth rates, and enhanced immunity of fish. Health risk assessments based on the major environmental contaminants (mercury, PAHs and DDTs) in fish flesh showed that fish fed food waste based pellets are safer for consumption, when compared with those fed commercial feed pellets. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. GENOTYPING OF CLOSTRIDIUM PERFRINGENS FROM FRESH WATER FISH AND FISH PICKLES

    Directory of Open Access Journals (Sweden)

    Adarsh Jain

    2012-08-01

    Full Text Available This study aims to evaluate the genotypes of Clostridium perfringens in fish and fish based products from Tamil Nadu and Kerala states of India. A total of 301 samples consisting intestinal contents of freshwater fish (234 from various dams, freshwater lakes, ponds, retail shops and markets and fish pickles (67 obtained from randomly selected retail shops and supermarkets were investigated. Bacterial isolations, identifications and phenotypic characterization of virulence factors were carried out as per standard microbiological procedures. Genotyping of the C. perfringens isolates were done by amplifying four major lethal toxin genes namely- alpha toxin gene (cpa, beta toxin gene (cpb, epsilon toxin gene (etx, iota toxin gene (iA in a Thermal Cycler. Isolates were also screened for the presence of enterotoxin gene (cpe and beta2 toxin gene (cpb2 by single step PCR. Biochemical tests and phenotypic determination of virulence factors tentatively identified 82 (27.24% isolates of C. perfringens. In PCR assay, all 82 (100% isolates harbored cpa toxin genes of C. perfringens, however, 65 (79.26% isolates also carried additional cpb2 toxin genes. None of the isolates were found positive for beta, epsilon, iota and enterotoxin genes. Genotyping of the 82 isolates by PCR revealed that all the isolated bacteria were belonged to C. perfringens type A and both cpa and cpb2 toxin genes were prevalent among the isolates of C. perfringens type A, impending the risk of pathogenicity to human via freshwater fish and fish pickles.

  16. How many fish in a tank? Constructing an automated fish counting system by using PTV analysis

    Science.gov (United States)

    Abe, S.; Takagi, T.; Takehara, K.; Kimura, N.; Hiraishi, T.; Komeyama, K.; Torisawa, S.; Asaumi, S.

    2017-02-01

    Because escape from a net cage and mortality are constant problems in fish farming, health control and management of facilities are important in aquaculture. In particular, the development of an accurate fish counting system has been strongly desired for the Pacific Bluefin tuna farming industry owing to the high market value of these fish. The current fish counting method, which involves human counting, results in poor accuracy; moreover, the method is cumbersome because the aquaculture net cage is so large that fish can only be counted when they move to another net cage. Therefore, we have developed an automated fish counting system by applying particle tracking velocimetry (PTV) analysis to a shoal of swimming fish inside a net cage. In essence, we treated the swimming fish as tracer particles and estimated the number of fish by analyzing the corresponding motion vectors. The proposed fish counting system comprises two main components: image processing and motion analysis, where the image-processing component abstracts the foreground and the motion analysis component traces the individual's motion. In this study, we developed a Region Extraction and Centroid Computation (RECC) method and a Kalman filter and Chi-square (KC) test for the two main components. To evaluate the efficiency of our method, we constructed a closed system, placed an underwater video camera with a spherical curved lens at the bottom of the tank, and recorded a 360° view of a swimming school of Japanese rice fish (Oryzias latipes). Our study showed that almost all fish could be abstracted by the RECC method and the motion vectors could be calculated by the KC test. The recognition rate was approximately 90% when more than 180 individuals were observed within the frame of the video camera. These results suggest that the presented method has potential application as a fish counting system for industrial aquaculture.

  17. Reproductive biology of weakly electric fish Eigenmannia trilineata López and Castello, 1966 (Teleostei, Sternopygidae

    Directory of Open Access Journals (Sweden)

    Júlia Giora

    2009-06-01

    Full Text Available This study described the reproductive biology of a population of the weakly electric fish Eigenmannia trilineata from southern Brazil, providing the information on the estimation of reproductive period, fecundity, spawning type, first maturation size, and analysis of gonadal morphology and histology of the species, relating these data to alimentary and abiotic characters. The species showed a relatively long reproductive period, a relative fecundity of 0.27 oocytes per mg of total weight and a parcelled spawning type. First maturation size estimated for the females was 80.5 mm and for the males 63.5 mm of total length. Sex ratio did not differ from 1:1 under a X²test (α= 0.01 during all the sampled months. Sexual dimorphism was related to total length, and males had larger total length than females. The abiotic factors photoperiod and water conductivity presented significant correlations with female GSI, while male GSI presented a significant correlation only with photoperiod.Este trabalho descreve a biologia reprodutiva de uma população do peixe elétrico Eigenmannia trilineata do Sul do Brasil. São apresentadas informações a respeito do período reprodutivo, fecundidade, tipo de desova, tamanho de primeira maturação, morfologia e histologia das gônadas da espécie, relacionando estes dados a caracteres alimentares e abióticos. A espécie apresentou período reprodutivo relativamente longo, com fecundidade relativa de 0,27 ovócito por miligrama do peso da fêmea e desova do tipo parcelada. O tamanho de primeira maturação gonadal estimado para fêmeas foi 80,5 mm e para machos, 63,5 mm de comprimento total. A proporção sexual, testada pelo teste X² (Α= 0.01, foi de 1:1 durante todos os meses amostrados; dimorfismo sexual relacionado ao comprimento total foi detectado, possuindo os machos um maior comprimento total. Dos fatores abióticos testados, fotoperíodo e condutividade da água mostraram correlação significativa com o

  18. Fishing drives declines in fish parasite diversity and has variable effects on parasite abundance.

    Science.gov (United States)

    Wood, Chelsea L; Sandin, Stuart A; Zgliczynski, Brian; Guerra, Ana Sofía; Micheli, Fiorenza

    2014-07-01

    Despite the ubiquity and ecological importance of parasites, relatively few studies have assessed their response to anthropogenic environmental change. Heuristic models have predicted both increases and decreases in parasite abundance in response to human disturbance, with empirical support for both. However, most studies focus on one or a few selected parasite species. Here, we assess the abundance of parasites of seven species of coral reef fishes collected from three fished and three unfished islands of the Line Islands archipelago in the central equatorial Pacific. Because we chose fish hosts that spanned different trophic levels, taxonomic groups, and body sizes, we were able to compare parasite responses across a broad cross section of the total parasite community in the presence and absence of fishing, a major human impact on marine ecosystems. We found that overall parasite species richness was substantially depressed on fished islands, but that the response of parasite abundance varied among parasite taxa: directly transmitted parasites were significantly more abundant on fished than on unfished islands, while the reverse was true for trophically transmitted parasites. This probably arises because trophically transmitted parasites require multiple host species, some of which are the top predators most sensitive to fishing impacts. The increase in directly transmitted parasites appeared to be due to fishing-driven compensatory increases in the abundance of their hosts. Together, these results provide support for the predictions of both heuristic models, and indicate that the direction of fishing's impact on parasite abundance is mediated by parasite traits, notably parasite transmission strategies.

  19. Food wastes as fish feeds for polyculture of low-trophic-level fish: bioaccumulation and health risk assessments of heavy metals in the cultured fish.

    Science.gov (United States)

    Cheng, Zhang; Lam, Cheung-Lung; Mo, Wing-Yin; Nie, Xiang-Ping; Choi, Wai-Ming; Man, Yu-Bon; Wong, Ming-Hung

    2016-04-01

    The major purpose of this study was to use different types of food wastes which serve as the major sources of protein to replace the fish meal used in fish feeds to produce quality fish. Two types of food waste-based feed pellets FW A (with cereals) and FW B (with cereals and meat products) and the commercial feed Jinfeng® were used to culture fingerlings of three low-trophic-level fish species: bighead carp, grass carp, and mud carp (in the ratio of 1:3:1) for 1 year period in the Sha Tau Kok Organic Farm in Hong Kong. Heavy metal concentrations in all of the fish species fed with food waste pellets and commercial pellets in Sha Tau Kok fish ponds were all below the local and international maximum permissible levels in food. Health risk assessments indicated that human consumption of the fish fed with food waste feed pellets was safe for the Hong Kong residents. The present results revealed that recycling of food waste for cultivating low-trophic-level fish (mainly herbivores and detritus feeders) is feasible, and at the same time will ease the disposal pressure of food waste, a common problem of densely populated cities like Hong Kong.

  20. Hawaii ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, marine, estuarine, and native stream fish species in coastal Hawaii. Vector polygons in this data...

  1. Fish crackers development from minced fish and starch: an innovative approach to a traditional product

    Directory of Open Access Journals (Sweden)

    Cristiane Rodrigues Pinheiro Neiva

    2011-12-01

    Full Text Available This study aimed to develop sensory acceptable, high nutritional value fish crackers that could be kept at room temperature for 180 days. Minced fish of different low-value species was the raw material employed to produce two types of fish crackers: a the traditional keropok cracker, which was expanded by deep frying; and b a low-fat fish cracker, expanded by microwave cooking. The protein content of the fried fish crackers (FFCs and that of the microwaved fish crackers (MFCs were high (10.86 and 14.70%, respectively. The essential amino acid contents of the two types of fish cracker were above the FAO requirements for adults, and the lysine content was above the requirements for children. Sensory analysis, performed by adult panelists, resulted in a general level of acceptability of 90% for the MFCs and of 97% for the FFCs. Vacuum packaging maintained microbiological and physicochemical properties for a storage period of 180 days at room temperature.

  2. Electrospun fish protein fibers as a biopolymer-based carrier – implications for oral protein delivery

    DEFF Research Database (Denmark)

    Boutrup Stephansen, Karen; García-Díaz, María; Jessen, Flemming

    2014-01-01

    Purpose: Protein-based electrospun fibers have emerged as novel nanostructured materials for tissue engineering and drug delivery due to their unique structural characteristics, biocompatibility and biodegradability. The aim of this study was to explore the use of electrospun fibers based on fish...... sarcoplasmic proteins as an oral delivery platform for biopharmaceuticals, using insulin as a model protein. Methods: Fish sarcoplasmic proteins (FSP) were isolated from fresh cod and electrospun into nanomicrofibers using insulin as a model payload. The morphology of FSP fibers was characterized using...... differentiated Caco-2 cell monolayers was followed by RP-HPLC and ELISA, and the transepithelial electrical resistance (TEER) was measured before and after the experiment. Cell viability was assessed by the MTS/PMS assay. Results: Insulin was encapsulated in the electrospun FSP fibers with high efficiency, high...

  3. Do fish have rights in artisanal fisheries?

    Directory of Open Access Journals (Sweden)

    Mustapha MK

    2013-09-01

    Full Text Available Artisanal fishers in developing world are unaware that fish are capable of suffering or discomfort, though researches have shown that fish do feel pain. Five fish welfare domains have been identified which constitute their rights in their environment. The needs of wild fish are usually provided in their natural, undisturbed and unperturbed aquatic environment, of which the fish will prefer. However, various anthropogenic activities by humans (including artisanal fisheries itself and some natural perturbations in the watershed, riparian zone, water body of the fish habitat and on the fish tend to take away these needs thereby compromising the fish welfare. These activities include environmental degradation, boat/canoe building, use of motorized engine boats/canoes, use of active and passive fishing gears, obnoxious cultural, religious and social fishing practices, fish harvesting, handling and processing among others. One way to understand the welfare needs of an individual fish is to understand its biology. Poor welfare conditions could then be assessed by how far the individual fish has deviated from the normal conditions. Non-intrusive signs based on the health, behavior, morphological anomalies, swimming, reduction in population and growth, outbreak of parasitic infections, injuries and loss of condition can be used to assess fish whose welfare has been compromised. Artisanal fishers should not only be concerned with catch, but, also the welfare of the fish being caught. This is because if the welfare of the fish is compromised, it is going to definitely affect the catch. As indispensable as fish is to humans, humans should not derive its pleasure at the expense of fish suffering. Human activities that impinge on the welfare of wild fish may not necessarily be stopped, but at least minimized in order to have continued sustainable artisanal exploitation of the fisheries.

  4. The control of the upstream movement of fish with pulsated direct current

    Science.gov (United States)

    McLain, Alberton L.

    1957-01-01

    Alternating-current electromechanical devices installed in the mouths of streams have proved effective in stopping the spawning migrations of the parasitic sea lamprey (Petromyzon marinus) which has seriously damaged Great Lakes fisheries. In a few streams, excessive mortality has occurred to other fish at the alternating-current barriers. A direct-current unit was developed in an attempt to reduce this mortality. This direct-current “diversion device” consists of a row of suspended negative electrodes which begins at the end of a trap wing and extends across the river at a downstream angle of 45° and a series of pipes (positive electrodes) driven into the stream bank. A second array, consisting of horizontal pipes installed downstream and parallel to the suspended electrodes and connected to a series of rods driven into the bank near the positive electrodes, controls the electrical field and dissipates the collecting influence of the positive side of the circuit. The electrical field is established from the end of the trap wing to the opposite bank. Fish are diverted away from the negative electrodes and toward the bank near which the trap is located. The array is activiated by pulsated direct current of essentially square wave shape with pulses at a duty cycle of 0.66 and a repetition rate of 3 per second. Direct-current diversion devices were operated in conjunction with alternating-current barriers during 1956 in the Chocolay River, Marquette County, and the Silver River, Baraga County, Michigan.

  5. Colville Tribal Fish Hatchery, annual report 2001

    International Nuclear Information System (INIS)

    2001-01-01

    Federal hydropower projects as well as private power utility systems have had a devastating impact upon anadromous fish resources that once flourished in the Columbia River and it's tributaries. Several areas were completely blocked to anadromous fish by dams, causing the native people who's number one food resource was salmon to rely entirely upon resident fish to replace lost fisheries resources. The Colville Tribal Fish Hatchery is an artificial production program to partially mitigate for anadromous fish losses in the ''Blocked Area'' above Chief Joseph and Grand Coulee Dams pursuant to Resident Fish Substitution Policy of the Northwest Power Planning Councils Fish and Wildlife Program. The hatchery was accepted into the Council's Fish and Wildlife Program in 1984 as a resident fish substitution measure and the hatchery was completed in 1990. The minimum production quota for this facility is 22,679 kg (50,000 lbs.) of trout. To achieve this quota the Colville Tribal Hatchery was scheduled to produce 174,000 fingerling rainbow trout (5 grams/fish), 330,000 sub-yearling rainbow trout (15 grams/fish), 80,000 legal size rainbow trout (90 grams/fish), 196,000 fingerling brook trout (5 grams/fish), 330,000 subyearling brook trout (15 grams/fish) and 60,000 lahontan cutthroat trout (15 grams/fish) in 2001. All fish produced are released into reservation waters, including boundary waters in an effort to provide a successful subsistence /recreational fishery for Colville Tribal members as well as a successful non-member sport fishery. The majority of the fish distributed from the facility are intended to provide a ''carry-over'' fishery. Fish produced at the facility are intended to be capable of contributing to the natural production component of the reservation fish populations. Contribution to the natural production component will be achieved by producing and releasing fish of sufficient quality and quantity for fish to survive to spawning maturity, to spawn

  6. Cowlitz Falls fish passage

    International Nuclear Information System (INIS)

    1995-09-01

    The upper Cowlitz was once home to native salmon and steelhead. But the combined impacts of overharvest, farming, logging and road building hammered fish runs. And in the 1960s, a pair of hydroelectric dams blocked the migration path of ocean-returning and ocean-going fish. The lower Cowlitz still supports hatchery runs of chinook, coho and steelhead. But some 200 river miles in the upper river basin--much of it prime spawning and rearing habitat--have been virtually cut off from the ocean for over 26 years. Now the idea is to trap-and-haul salmon and steelhead both ways and bypass previously impassable obstacles in the path of anadromous fish. The plan can be summarized, for the sake of explanation, in three steps: (1) trap and haul adult fish--collect ocean-returning adult fish at the lowermost Cowlitz dam, and truck them upstream; (2) reseed--release the ripe adults above the uppermost dam, and let them spawn naturally, at the same time, supplement these runs with hatchery born fry that are reared and imprinted in ponds and net pens in the watershed; (3) trap and haul smolts--collection the new generation of young fish as they arrive at the uppermost Cowlitz dam, truck them past the three dams, and release them to continue their downstream migration to the sea. The critical part of any fish-collection system is the method of fish attraction. Scientists have to find the best combination of attraction system and screens that will guide young fish to the right spot, away from the turbine intakes. In the spring of 1994 a test was made of a prototype system of baffles and slots on the upriver face of the Cowlitz Falls Dam. The prototype worked at 90% efficiency in early tests, and it worked without the kind of expensive screening devices that have been installed on other dams. Now that the success of the attraction system has been verified, Harza engineers and consultants will design and build the appropriate collection part of the system

  7. Swimbladder on Fish Target Strength

    Directory of Open Access Journals (Sweden)

    Sunardi

    2008-08-01

    Full Text Available This paper discusses of target strength (TS for the Selar boops (Oxeye scad and Megalaspis cordyla (Torpedo scad, the most commercially fish in Malaysia. TS can be determined from in situ measurements and acoustic calculation of fish model. TS value, depth, and position (x-y-z of targeted fish can be viewed from echogram using FQ-80 Analyzer by in situ measurement. X-ray imaged can be deployed to develop the acoustic fish model. The percentage of length and upper surface area for swimbladder to body fish of Selar boops more than Megalaspis cordyla can be measured after X-ray process. The percentage of width and volume of swimbladders to its each body are no significantly difference for both fish. These data of swimbladder physic support the result of in situ measurement which TS of Megalaspis cordyla stronger Selar boops.

  8. Sub-indicator: Prey fish

    Science.gov (United States)

    Weidel, Brian C.; Dunlop, Erin

    2017-01-01

    Prey fish communities across the Great Lakes continue to change, although the direction and magnitude of those changes are not consistent across the lakes. The metrics used to categorize prey fish status in this and previous periods are based on elements that are common among each of the lake’s Fish Community Objectives and include diversity and the relative role of native species in the prey fish communities. The diversity index categorized three of lakes as ‘fair’, while Superior and Erie were ‘good’ (Table 1). The short term trend, from the previous period (2008-2010) to the current period (2011-2014) found diversity in Erie and Superior to be unchanging, but the other three lakes to be ‘deteriorating’, resulting in an overall trend categorization of ‘undetermined’ (Table 1). The long term diversity trend suggested Lakes Superior and Erie have the most diverse prey communities although the index for those prey fish have been quite variable over time (Figure 1). In Lake Huron, where non-native alewife have substantially declined, the diversity index has also declined. The continued dominance of alewife in Lake Ontario (96% of the prey fish biomass) resulted in the lowest diversity index value (Figure 1). The proportion of native species within the community was judged as ‘good’ in Lakes Superior and Huron, ‘fair’ in Michigan and Erie and ‘poor’ in Ontario (Table 2). The short term trend was improving in in all lakes except Michigan (‘deteriorating’) and Ontario (‘unchanging’), resulting in an overall short term trend of ‘undetermined’ (Table 2). Over the current period, Lake Superior consistently had the highest proportion native prey fish (87%) while Lake Ontario had the lowest (1%) (Figure 2). Lake Michigan’s percent native has declined as round goby increase and comprises a greater proportion of the community. Native prey fish make up 51% of Lake Erie, although basin-specific values differed (Figure 2). Most notably

  9. Fish wariness is a more sensitive indicator to changes in fishing pressure than abundance, length or biomass.

    Science.gov (United States)

    Goetze, Jordan S; Januchowski-Hartley, Fraser A; Claudet, Joachim; Langlois, Tim J; Wilson, Shaun K; Jupiter, Stacy D

    2017-06-01

    Identifying the most sensitive indicators to changes in fishing pressure is important for accurately detecting impacts. Biomass is thought to be more sensitive than abundance and length, while the wariness of fishes is emerging as a new metric. Periodically harvested closures (PHCs) that involve the opening and closing of an area to fishing are the most common form of fisheries management in the western Pacific. The opening of PHCs to fishing provides a unique opportunity to compare the sensitivity of metrics, such as abundance, length, biomass and wariness, to changes in fishing pressure. Diver-operated stereo video (stereo-DOV) provides data on fish behavior (using a proxy for wariness, minimum approach distance) simultaneous to abundance and length estimates. We assessed the impact of PHC protection and harvesting on the abundance, length, biomass, and wariness of target species using stereo-DOVs. This allowed a comparison of the sensitivity of these metrics to changes in fishing pressure across four PHCs in Fiji, where spearfishing and fish drives are common. Before PHCs were opened to fishing they consistently decreased the wariness of targeted species but were less likely to increase abundance, length, or biomass. Pulse harvesting of PHCs resulted in a rapid increase in the wariness of fishes but inconsistent impacts across the other metrics. Our results suggest that fish wariness is the most sensitive indicator of fishing pressure, followed by biomass, length, and abundance. The collection of behavioral data simultaneously with abundance, length, and biomass estimates using stereo-DOVs offers a cost-effective indicator of protection or rapid increases in fishing pressure. Stereo-DOVs can rapidly provide large amounts of behavioral data from monitoring programs historically focused on estimating abundance and length of fishes, which is not feasible with visual methods. © 2017 by the Ecological Society of America.

  10. The economics of fishing the high seas.

    Science.gov (United States)

    Sala, Enric; Mayorga, Juan; Costello, Christopher; Kroodsma, David; Palomares, Maria L D; Pauly, Daniel; Sumaila, U Rashid; Zeller, Dirk

    2018-06-01

    While the ecological impacts of fishing the waters beyond national jurisdiction (the "high seas") have been widely studied, the economic rationale is more difficult to ascertain because of scarce data on the costs and revenues of the fleets that fish there. Newly compiled satellite data and machine learning now allow us to track individual fishing vessels on the high seas in near real time. These technological advances help us quantify high-seas fishing effort, costs, and benefits, and assess whether, where, and when high-seas fishing makes economic sense. We characterize the global high-seas fishing fleet and report the economic benefits of fishing the high seas globally, nationally, and at the scale of individual fleets. Our results suggest that fishing at the current scale is enabled by large government subsidies, without which as much as 54% of the present high-seas fishing grounds would be unprofitable at current fishing rates. The patterns of fishing profitability vary widely between countries, types of fishing, and distance to port. Deep-sea bottom trawling often produces net economic benefits only thanks to subsidies, and much fishing by the world's largest fishing fleets would largely be unprofitable without subsidies and low labor costs. These results support recent calls for subsidy and fishery management reforms on the high seas.

  11. Relation of contaminants to fish intersex in riverine sport fishes.

    Science.gov (United States)

    Grieshaber, Casey A; Penland, Tiffany N; Kwak, Thomas J; Cope, W Gregory; Heise, Ryan J; Law, J Mac; Shea, Damian; Aday, D Derek; Rice, James A; Kullman, Seth W

    2018-06-20

    Endocrine active compounds (EACs) are pollutants that have been recognized as an emerging and widespread threat to aquatic ecosystems globally. Intersex, the presence of female germ cells within a predominantly male gonad, is considered a biomarker of endocrine disruption caused by EACs. We measured a suite of EACs and assessed their associated impacts on fish intersex occurrence and severity in a large, regulated river system in North Carolina and South Carolina, USA. Our specific objective was to determine the relationship of contaminants in water, sediment, and fish tissue with the occurrence and severity of the intersex condition in wild, adult black bass (Micropterus), sunfish (Lepomis), and catfish (Ictaluridae) species at 11 sites located on the Yadkin-Pee Dee River. Polycyclic aromatic hydrocarbons (PAHs), ethinylestradiol (EE2), and heavy metals were the most prevalent contaminants that exceeded effect levels for the protection of aquatic organisms. Fish intersex condition was most frequently observed and most severe in black basses and was less frequently detected and less severe in sunfishes and catfishes. The occurrence of the intersex condition in fish showed site-related effects, rather than increasing longitudinal trends from upstream to downstream. Mean black bass and catfish tissue contaminant concentrations were higher than that of sunfish, likely because of the latter's lower trophic position in the food web. Principal component analysis identified waterborne PAHs as the most correlated environmental contaminant with intersex occurrence and severity in black bass and sunfish. As indicated by the intersex condition, EACs have adverse but often variable effects on the health of wild sport fishes in this river, likely due to fluctuations in EAC inputs and the dynamic nature of the riverine system. These findings enhance the understanding of the relationship between contaminants and fish health and provide information to guide ecologically

  12. Comparative studies of metals in fish organs, sediments and water from Nigerian fresh water fish ponds

    International Nuclear Information System (INIS)

    Ipinmoroti, K.O.; Oshodi, A.A.; Owolabi, R.A.

    1997-01-01

    Fish samples (Illisha africana) were collected from six man-made fish pond in Edo and Ondo states, Nigeria. Some organs of the fish sediment and water from the fish habitat were analysed for Cd, Pb, Hg, Ca, Fe, Zn, Cu and Cr, Physico-chemical properties of water samples from the ponds were also re-corded. The concentration of the metals varied in the sediment water as well as in different organs of the fish. However, chromium was absent in all the samples. The descending order of metal concentration in fish organs was: gills intestine, head and muscle. To avoid harmful accumulation of these metals in the human system, the gills and the intestine should preferably be discarded while processing fish for consumption. The head with a relatively high concentration of calcium might be useful in feed formulation. (author)

  13. Fish4Knowledge collecting and analyzing massive coral reef fish video data

    CERN Document Server

    Chen-Burger, Yun-Heh; Giordano, Daniela; Hardman, Lynda; Lin, Fang-Pang

    2016-01-01

    This book gives a start-to-finish overview of the whole Fish4Knowledge project, in 18 short chapters, each describing one aspect of the project. The Fish4Knowledge project explored the possibilities of big video data, in this case from undersea video. Recording and analyzing 90 thousand hours of video from ten camera locations, the project gives a 3 year view of fish abundance in several tropical coral reefs off the coast of Taiwan. The research system built a remote recording network, over 100 Tb of storage, supercomputer processing, video target detection and tracking, fish species recognition and analysis, a large SQL database to record the results and an efficient retrieval mechanism. Novel user interface mechanisms were developed to provide easy access for marine ecologists, who wanted to explore the dataset. The book is a useful resource for system builders, as it gives an overview of the many new methods that were created to build the Fish4Knowledge system in a manner that also allows readers to see ho...

  14. Founders of fish culture - European origins

    Science.gov (United States)

    Fish, F.F.

    1936-01-01

    Just where true fish culture appeared in history depends entirely upon what one considers fish culture to be. If the transportation of fishes from regions of plenty to those of few is to be regarded as fish culture - as it is by some even today - then this story should start in remotest antiquity and deal with an amazing series of failures. However, fish culture to be classed as a science must include far more than mere transportation, it must include a deliberate effort on the part of man to master a technique of fish raising which will yield results far superior to Nature's. Accordingly, the wheel of history must be spun forward to the fifteenth century, A. D., when man first conceived the idea that with care and exactitude, he could improve upon Nature. The fish cultural efforts of the Chinese, the Egyptians, the Greeks, and the Romans may be skipped over in a hurry, for they represented little more than the transportation and rearing of wild fish. With the renaissance of modern civilization in Europe came the birth of scientific fish culture.

  15. Technical Resources for Fish and Shellfish Consumption

    Science.gov (United States)

    Information on ways to develop local fish advisories, access national state and local fish advisories, obtain information on fish tissue contamination and fish tissue studies, and access information on fish consumption and human health.

  16. Grande Ronde Basin Fish Habitat Enhancement Project, Annual Report 2002-2003.

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Vance

    2003-08-01

    On July 1, 1984 the Bonneville Power Administration and the Oregon Department of Fish and Wildlife entered into an agreement to initiate fish habitat enhancement work in the Joseph Creek subbasin of the Grande Ronde River Basin in northeast Oregon. In July of 1985 the Upper and Middle Grande Ronde River, and Catherine Creek subbasins were included in the intergovernmental contract, and on March 1, 1996 the Wallowa River subbasin was added. The primary goal of 'The Grande Ronde Basin Fish Habitat Enhancement Project' is to create, protect, and restore riparian and instream habitat for anadromous salmonids, thereby maximizing opportunities for natural fish production within the basin. This project provided for implementation of Program Measure 703 (C)(1), Action Item 4.2 of the Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program (NPPC, 1987), and continues to be implemented as offsite mitigation for mainstem fishery losses caused by the Columbia River hydro-electric system. All work conducted by the Oregon Department of Fish and Wildlife is on private lands and therefore requires that considerable time be spent developing rapport with landowners to gain acceptance of, and continued cooperation with this program throughout 10-15 year lease periods. This project calls for passive regeneration of habitat, using riparian exclosure fencing as the primary method to restore degraded streams to a normative condition. Active remediation techniques using plantings, off-site water developments, site-specific instream structures, or whole channel alterations are also utilized where applicable. Individual projects contribute to and complement ecosystem and basin-wide watershed restoration efforts that are underway by state, federal, and tribal agencies, and local watershed councils. Work undertaken during 2002 included: (1) Implementing 1 new fencing project in the Wallowa subbasin that will protect an additional 0.95 miles of stream

  17. A Mixed-Method Approach for Quantifying Illegal Fishing and Its Impact on an Endangered Fish Species.

    Science.gov (United States)

    Free, Christopher M; Jensen, Olaf P; Mendsaikhan, Bud

    2015-01-01

    Illegal harvest is recognized as a widespread problem in natural resource management. The use of multiple methods for quantifying illegal harvest has been widely recommended yet infrequently applied. We used a mixed-method approach to evaluate the extent, character, and motivations of illegal gillnet fishing in Lake Hovsgol National Park, Mongolia and its impact on the lake's fish populations, especially that of the endangered endemic Hovsgol grayling (Thymallus nigrescens). Surveys for derelict fishing gear indicate that gillnet fishing is widespread and increasing and that fishers generally use 3-4 cm mesh gillnet. Interviews with resident herders and park rangers suggest that many residents fish for subsistence during the spring grayling spawning migration and that some residents fish commercially year-round. Interviewed herders and rangers generally agree that fish population sizes are decreasing but are divided on the causes and solutions. Biological monitoring indicates that the gillnet mesh sizes used by fishers efficiently target Hovsgol grayling. Of the five species sampled in the monitoring program, only burbot (Lota lota) showed a significant decrease in population abundance from 2009-2013. However, grayling, burbot, and roach (Rutilus rutilus) all showed significant declines in average body size, suggesting a negative fishing impact. Data-poor stock assessment methods suggest that the fishing effort equivalent to each resident family fishing 50-m of gillnet 11-15 nights per year would be sufficient to overexploit the grayling population. Results from the derelict fishing gear survey and interviews suggest that this level of effort is not implausible. Overall, we demonstrate the ability for a mixed-method approach to effectively describe an illegal fishery and suggest that these methods be used to assess illegal fishing and its impacts in other protected areas.

  18. Trawl catch composition during different fishing intensity periods in two Mediterranean demersal fishing grounds

    Directory of Open Access Journals (Sweden)

    Pilar Sánchez

    2007-12-01

    Full Text Available The study was carried out in two fishing grounds on the Mediterranean continental shelf: one in the Adriatic Sea and one in the Catalan Sea. Samplings on board otter trawlers were performed from November 2002 to December 2003 in the Catalan Sea and from February 2003 to January 2004 in the Adriatic Sea. The Adriatic fishing ground was affected by high fishing intensity from January to June, while the Catalan area was highly exploited from September to February. Fishing activity in the Adriatic area was closed for 45 days, and 62 days in the Catalan area; both periods were in summer. Totals of 92 and 88 species were collected in the Adriatic and Catalan fishing grounds respectively. The species composition of the retained and discarded fractions showed close agreement between the two areas. Mullus barbatus showed very low discard rates in both areas, as well as Loligo vulgaris in the Catalan Sea and Merluccius merluccius in the Adriatic Sea. In both fishing grounds Squilla mantis showed high catch rates with low discards, except in March in the Catalan area. In the Adriatic Sea Liocarcinus depurator was characterized by large discard fractions. In both fishing grounds the retained fraction was slightly higher in the high fishing intensity periods than in the low intensity ones (Adriatic Sea: 0.613 vs 0.524; Catalan Sea: 0.597 vs 0.539, even though the Kruskall Wallis test revealed significant differences (p

  19. Fishes in a changing world: learning from the past to promote sustainability of fish populations.

    Science.gov (United States)

    Gordon, T A C; Harding, H R; Clever, F K; Davidson, I K; Davison, W; Montgomery, D W; Weatherhead, R C; Windsor, F M; Armstrong, J D; Bardonnet, A; Bergman, E; Britton, J R; Côté, I M; D'agostino, D; Greenberg, L A; Harborne, A R; Kahilainen, K K; Metcalfe, N B; Mills, S C; Milner, N J; Mittermayer, F H; Montorio, L; Nedelec, S L; Prokkola, J M; Rutterford, L A; Salvanes, A G V; Simpson, S D; Vainikka, A; Pinnegar, J K; Santos, E M

    2018-03-01

    Populations of fishes provide valuable services for billions of people, but face diverse and interacting threats that jeopardize their sustainability. Human population growth and intensifying resource use for food, water, energy and goods are compromising fish populations through a variety of mechanisms, including overfishing, habitat degradation and declines in water quality. The important challenges raised by these issues have been recognized and have led to considerable advances over past decades in managing and mitigating threats to fishes worldwide. In this review, we identify the major threats faced by fish populations alongside recent advances that are helping to address these issues. There are very significant efforts worldwide directed towards ensuring a sustainable future for the world's fishes and fisheries and those who rely on them. Although considerable challenges remain, by drawing attention to successful mitigation of threats to fish and fisheries we hope to provide the encouragement and direction that will allow these challenges to be overcome in the future. © 2018 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of The Fisheries Society of the British Isles.

  20. Fish Oncology: Diseases, Diagnostics, and Therapeutics.

    Science.gov (United States)

    Vergneau-Grosset, Claire; Nadeau, Marie-Eve; Groff, Joseph M

    2017-01-01

    The scientific literature contains a wealth of information concerning spontaneous fish neoplasms, although ornamental fish oncology is still in its infancy. The occurrence of fish neoplasms has often been associated with oncogenic viruses and environmental insults, making them useful markers for environmental contaminants. The use of fish, including zebrafish, as models of human carcinogenesis has been developed and knowledge gained from these models may also be applied to ornamental fish, although more studies are required. This review summarizes information available about fish oncology pertaining to veterinary clinicians. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. [Effects of submarine topography and water depth on distribution of pelagic fish community in minnan-taiwan bank fishing ground].

    Science.gov (United States)

    Fang, Shuimei; Yang, Shengyun; Zhang, Chengmao; Zhu, Jinfu

    2002-11-01

    According to the fishing record of the light-seine information vessel in Minnan-Taiwan bank ground during 1989 to 1999, the effects of submarine topography and water depth on distribution of pelagic fish community in Minnan-Taiwan bank fishing ground was studied. The results showed that the pelagic fish distributed concentratively, while the submarine topography and water depth varied widely, but in different fishing regions, the distribution of pelagic fishes was uneven. The distribution of fishing yield increased from north to south, and closed up from sides of the bank to south or north in the regions. Pelagic fish distributed mainly in mixed water in the southern Taiwan Strait, and in warm water in the Taiwan Strait. The central fishing grounds were at high salt regions. Close gathering regions of pelagic fish or central fishing ground would be varied with the seasonal variation of mixed water in the southern Taiwan Strait and warm water in the Taiwan Strait. Central fishing ground was not only related to submarine topography and water depth, but also related to wind direction, wind-power and various water systems. In the fishing ground, the gathering depth of pelagic fish was 30-60 m in spring and summer, and 40-80 m in autumn and winter.

  2. Fuel properties of biodiesel produced from the crude fish oil from the soapstock of marine fish

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Cherng-Yuan; Li, Rong-Ji [Department of Marine Engineering, National Taiwan Ocean, University, Keelung 20224 (China)

    2009-01-15

    The soapstock of a mixture of marine fish was used as the raw material to produce the biodiesel in this study. The soapstock was collected from discarded fish products. Crude fish oil was squeezed from the soapstock of the fish and refined by a series of processes. The refined fish oil was transesterified to produce biodiesel. The fuel properties of the biodiesel were analyzed. The experimental results showed that oleic acid (C18:1) and palmitic acid (C16:0) were the two major components of the marine fish-oil biodiesel. The biodiesel from the mixed marine fish oil contained a significantly greater amount of polyunsaturated fatty acids than did the biodiesel from waste cooking oil. In addition, the marine fish-oil biodiesel contained as high as 37.07 wt.% saturated fatty acids and 37.3 wt.% long chain fatty acids in the range between C20 and C22. Moreover, the marine fish-oil biodiesel appeared to have a larger acid number, a greater increase in the rate of peroxidization with the increase in the time that it was stored, greater kinematic viscosity, higher heating value, higher cetane index, more carbon residue, and a lower peroxide value, flash point, and distillation temperature than those of waste cooking-oil biodiesel. (author)

  3. Fish Oil in Diabetic Nephropathy

    DEFF Research Database (Denmark)

    Rossing, Peter; Hansen, Birgitte V.; Nielsen, Flemming S.

    1996-01-01

    OBJECTIVE: Recent studies in nondiabetic kidney diseases suggest that dietary supplementation with n-3 polyunsaturated fatty acids (fish oil) may have beneficial effects on albuminuria, kidney function, arterial blood pressure, and dyslipidemia. Therefore, we evaluated the long-term effect of fish...... in the fish oil compared with the placebo group. CONCLUSIONS: Our study does not suggest that fish oil has beneficial effects on albuminuria, kidney function, blood pressure, and dyslipidemia in normotensive IDDM patients suffering from diabetic nephropathy....

  4. Traditional method of fish treatment, microbial count and palatability studies on spoiled fish

    Directory of Open Access Journals (Sweden)

    Abd Aziz, N. A.

    2013-01-01

    Full Text Available Aims: To evaluate the microbial count and palatability acceptance of spoiled fish after treatment with traditionally used naturalsolution.Methodology and results: To compare microbial count of spoiled fish before and after treatment with natural solution practicedby local people in Malaysia, 10 g of spoiled fish was respectively rinsed with 100 mL of 0.1% of natural solution such as Averrhoabilimbi extract, rice rinsed water, rice vinegar, Citrus aurantifolia extract, salt, flour, and Tamarindus indica extract. Flesh of fishrinsed with rice vinegar was found to be able to reduce microbial count (CFU/mL = 0.37 X 107 more than 4.5 times whencompared to spoiled fish (CFU/mL=1.67x 107. Spoiled fish that was treated with rice vinegar was prepared into a cutlet and fried.The cutlet was subjected to palatability acceptance study by a group of residents in Palm Court Condominium, Brickfields, KualaLumpur. The palatability study from the Cronbach alpha shown that the taste have the reliability of 0.802, the aroma has thereliability of 0.888, colour with the reliability of 0.772, texture or mouth feel have reliability of 0.840 and physical structure of thecutlet is 0.829.Conclusion, significance and impact of study: Treatment of spoiled fish using rice vinegar as practice by local peopletraditionally shown a significant reduction in microbial count and the vinegar-treated fish could be developed into a product that issafe and acceptable by the consumer.

  5. Effects of recreational fishing on three fish species from the Posidonia oceanica meadows off Minorca (Balearic archipelago, western Mediterranean

    Directory of Open Access Journals (Sweden)

    Luis Cardona

    2007-12-01

    Full Text Available Experimental fishing and visual censuses were conducted at nine Posidonia oceanica sites off Minorca exposed to different levels of fishing intensity to assess the effects of recreational fishing on the species that dominate the catch. Total catch per unit effort (CPUE was highly seasonal and a statistically significant interaction term existed between the season and the level of fishing intensity. CPUE decreased everywhere at the end of the fishing season (autumn, but such a reduction was more intense at those sites exposed to the highest level of fishing. Visual censuses confirmed that there was a lower abundance of vulnerable fish in autumn. Differences vanished in spring probably because fish reshuffled between the considered sites throughout the winter, when the level of fishing intensity was extremely low. Although the average total lengths of Serranus scriba and Diplodus annularis were unaffected by the level of fishing intensity, the average total length of Coris julis was smaller at the most heavily fished sites. In conclusion, recreational fishing has a relevant impact on most of the exploited species and some of the seasonality reported for the Posidonia oceanica fish assemblages might be caused by the seasonality of the fishery.

  6. Iodine stability and sensory quality of fermented fish and fish sauce produced with the use of iodated salt.

    Science.gov (United States)

    Chanthilath, Boualapha; Chavasit, Visith; Chareonkiatkul, Somsri; Judprasong, Kunchit

    2009-06-01

    Universal salt iodization promotes the use of iodated salt for producing industrial food products, although it might affect product quality and iodine stability. To assess iodine loss during fermentation of fermented fish and fish sauces produced by using iodated salt and the effect on product sensory quality. Fermented fish and fish sauces were produced with iodated rock and grain sea salts (approximately 30 ppm iodine). Fermented fish was prepared from freshwater fish mixed with salt and rice bran and fermented for 6 months at room temperature. Fish sauces were prepared by mixing anchovy with salt and fermenting either exposed to sunlight or in the shade for 12 months. Residual iodine was determined with a spectrophotometer at day 0 and months 1, 3, and 6 for fermented fish and day 0 and months 3, 6, and 12 for fish sauces. After fermentation, the products were tested for sensory acceptability by Laotian and Thai panelists (approximately 50 in each panel) after they were cooked and served in the traditional manner. After fermentation, the level of residual iodine was 7.61 ppm (16% loss) infermented fish, 5.57 ppm (55% loss) in fish sauce prepared with exposure to sunlight, and 9.52 ppm (13% loss) in fish sauce prepared in the shade. Sensory qualities of the products that were produced from fortified and unfortified salts as well as dishes prepared from these products were not significantly different (p > 0.05). It is feasible to produce fermented fish and fish sauces with iodated salt and maintain acceptable iodine levels.

  7. Mercury in fish from two Nicaraguan lakes: A recommendation for increased monitoring of fish for international commerce

    International Nuclear Information System (INIS)

    McCrary, Jeffrey K.; Castro, Mark; McKaye, Kenneth R.

    2006-01-01

    We measured total mercury concentrations in water and fish of Lake Managua and Lake Apoyo. Water mercury concentrations were 10-fold higher in Lake Managua than in Lake Apoyo, although differences in mercury concentration in the most common native fish were not significant. One-fourth of the commercially fished tilapia in Lake Managua exceeded maximum recommended mercury levels for consumption among pregnant women and other at-risk groups, although bioavailability to fishes was lower than in previously studied sites in Brazil and Western Maryland. The lower bioavailiability may present important information for management options to reduce mercury exposure to fishes and humans. We recommend closer mercury monitoring among freshwater fish destined for international commerce. - Fish commonly exported into the international food supply may be contaminated with mercury

  8. Mercury in fish from two Nicaraguan lakes: A recommendation for increased monitoring of fish for international commerce

    Energy Technology Data Exchange (ETDEWEB)

    McCrary, Jeffrey K. [University of Central America, Apdo. 69, Managua (Nicaragua) and College of Natural Resources, Virginia Tech, Blacksburg, VA 24061 (United States)]. E-mail: jmccrary2@yahoo.com; Castro, Mark [Appalachian Laboratory, University of Maryland Center for Environmental Science, 301 Braddock Road, Frostburg, MD 21532 (United States); McKaye, Kenneth R. [University of Central America, Apdo. 69, Managua (Nicaragua); Appalachian Laboratory, University of Maryland Center for Environmental Science, 301 Braddock Road, Frostburg, MD 21532 (United States)

    2006-06-15

    We measured total mercury concentrations in water and fish of Lake Managua and Lake Apoyo. Water mercury concentrations were 10-fold higher in Lake Managua than in Lake Apoyo, although differences in mercury concentration in the most common native fish were not significant. One-fourth of the commercially fished tilapia in Lake Managua exceeded maximum recommended mercury levels for consumption among pregnant women and other at-risk groups, although bioavailability to fishes was lower than in previously studied sites in Brazil and Western Maryland. The lower bioavailiability may present important information for management options to reduce mercury exposure to fishes and humans. We recommend closer mercury monitoring among freshwater fish destined for international commerce. - Fish commonly exported into the international food supply may be contaminated with mercury.

  9. Fish Karyome version 2.1: a chromosome database of fishes and other aquatic organisms.

    Science.gov (United States)

    Nagpure, Naresh Sahebrao; Pathak, Ajey Kumar; Pati, Rameshwar; Rashid, Iliyas; Sharma, Jyoti; Singh, Shri Prakash; Singh, Mahender; Sarkar, Uttam Kumar; Kushwaha, Basdeo; Kumar, Ravindra; Murali, S

    2016-01-01

    A voluminous information is available on karyological studies of fishes; however, limited efforts were made for compilation and curation of the available karyological data in a digital form. 'Fish Karyome' database was the preliminary attempt to compile and digitize the available karyological information on finfishes belonging to the Indian subcontinent. But the database had limitations since it covered data only on Indian finfishes with limited search options. Perceiving the feedbacks from the users and its utility in fish cytogenetic studies, the Fish Karyome database was upgraded by applying Linux, Apache, MySQL and PHP (pre hypertext processor) (LAMP) technologies. In the present version, the scope of the system was increased by compiling and curating the available chromosomal information over the globe on fishes and other aquatic organisms, such as echinoderms, molluscs and arthropods, especially of aquaculture importance. Thus, Fish Karyome version 2.1 presently covers 866 chromosomal records for 726 species supported with 253 published articles and the information is being updated regularly. The database provides information on chromosome number and morphology, sex chromosomes, chromosome banding, molecular cytogenetic markers, etc. supported by fish and karyotype images through interactive tools. It also enables the users to browse and view chromosomal information based on habitat, family, conservation status and chromosome number. The system also displays chromosome number in model organisms, protocol for chromosome preparation and allied techniques and glossary of cytogenetic terms. A data submission facility has also been provided through data submission panel. The database can serve as a unique and useful resource for cytogenetic characterization, sex determination, chromosomal mapping, cytotaxonomy, karyo-evolution and systematics of fishes. Database URL: http://mail.nbfgr.res.in/Fish_Karyome. © The Author(s) 2016. Published by Oxford University Press.

  10. Cyprinid fishes: systematics, biology, and exploitation

    National Research Council Canada - National Science Library

    Winfield, Ian J; Nelson, Joseph S

    1991-01-01

    .... As this family is extremely important as forage fish for other animals, as food fish for humans and are commonly used as models in experimental work, the book will be of great interest to all those with an interest in freshwater fish, fish ecology, fisheries biology and aquaculture systems.

  11. Poisoning - fish and shellfish

    Science.gov (United States)

    Fish poisoning; Dinoflagellate poisoning; Seafood contamination; Paralytic shellfish poisoning; Ciguatera poisoning ... algae and algae-like organisms called dinoflagellates. Small fish that eat the algae become contaminated. If larger ...

  12. Bacterial zoonoses of fishes: a review and appraisal of evidence for linkages between fish and human infections.

    Science.gov (United States)

    Gauthier, David T

    2015-01-01

    Human contact with and consumption of fishes presents hazards from a range of bacterial zoonotic infections. Whereas many bacterial pathogens have been presented as fish-borne zoonoses on the basis of epidemiological and phenotypic evidence, genetic identity between fish and human isolates is not frequently examined or does not provide support for transmission between these hosts. In order to accurately assess the zoonotic risk from exposure to fishes in the context of aquaculture, wild fisheries and ornamental aquaria, it is important to critically examine evidence of linkages between bacteria infecting fishes and humans. This article reviews bacteria typically presented as fish-borne zoonoses, and examines the current strength of evidence for this classification. Of bacteria generally described as fish-borne zoonoses, only Mycobacterium spp., Streptococcus iniae, Clostridium botulinum, and Vibrio vulnificus appear to be well-supported as zoonoses in the strict sense. Erysipelothrix rhusiopathiae, while transmissible from fishes to humans, does not cause disease in fishes and is therefore excluded from the list. Some epidemiological and/or molecular linkages have been made between other bacteria infecting both fishes and humans, but more work is needed to elucidate routes of transmission and the identity of these pathogens in their respective hosts at the genomic level. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Fish and wildlife surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Poston, T.M.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the monitoring of radioactive contaminants in fish and wildlife species that inhabit the Colombia River and Hanford Site. Wildlife have access to areas of the Site containing radioactive contamination, and fish can be exposed to contamination in spring water entering the river along the shoreline. Therefore, samples are collected at various locations annually, generally during the hunting or fishing season, for selected species.

  14. Fish and wildlife surveillance

    International Nuclear Information System (INIS)

    Poston, T.M.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report summarizes the monitoring of radioactive contaminants in fish and wildlife species that inhabit the Colombia River and Hanford Site. Wildlife have access to areas of the Site containing radioactive contamination, and fish can be exposed to contamination in spring water entering the river along the shoreline. Therefore, samples are collected at various locations annually, generally during the hunting or fishing season, for selected species

  15. ILLEGAL FISHING SEBAGAI KEJAHATAN KORPORASI SUATU TEROBOSAN HUKUM PIDANA MENGADILI KEJAHATAN ILLEGAL FISHING

    Directory of Open Access Journals (Sweden)

    Moch. Iqbal

    2012-11-01

    Full Text Available Cakupan, pengertian dan pemahaman illegal fishing yang dipahami dan dianut dalam hukum positif Indonesia adalah pencurian ikan yang berdampak dan berpengaruh besar terhadap perekonomian negara. Oleh karenanya esensi regulasi dan penindakan terhadap illegal fishing di Indonesia seharusnya dipahami pada penindakan pencurian ikan yang berskala besar, yang pada umumnya dilakukan oleh armada-armada asing, kapal-kapal asing yang illegal, yang telah pula berakibat merugikan perekonomian negara (Indonesia triliunan rupiah tiap tahunnya. Dengan model dan jenis pencurian yang berskala besar dan membahayakan perekonomian nasional tersebut, penanganan regulasinya patut diarahkan pada atau untuk mengatasi kejahatan-kejahatan berskala besar dan rumit (sophisticated, yang tergolong dalam jenis kejahatan white collar crime atau kejahatan korporasi. Mengenal dan memahami seluk beluk serta keberadaan kejahatan korporasi, bagi para penegak hukum adalah sebuah keharusan di era modern ini, oleh karenanya tulisan ini memfokuskan pada dua kata kunci (key word illegal fishing dan corporate crime. Mengetahui dan memahami konsep dan regulasi seputar illegal fishing serta kejahatan korporasi menjadi kontribusi penting dalam proses penegakan hukum. Dengan pemahaman atas illegal fishing dan kejahatan korporasi akan menjadi landasan yang kuat bagi setiap praktisi hukum, khususnya penegak hukum dalam berproses acara maupun menentukan jenis dan klasifikasi pertanggungjawaban pidana yang tepat dan benar bagi penegak hukum khususnya para hakim agar berani dan tidak ragu dalam menjatuhkan sanksi pada setiap pelaku illegal fishing atau pelaku kejahatan korporasi. Dengan hukuman yang tegas dan jelas serta pasti, para penegak hukum tidak saja menegakkan hukum dan keadilan melainkan juga telah menyelamatkan perekonomian negara, dengan mencegah potensi kehilangan kekayaan nasional, sebagai pelaksanaan dari fungsi hukum sebagai alat rekayasa sosial.   Coverage, insight, and

  16. Physiology of fish endocrine pancreas.

    Science.gov (United States)

    Plisetskaya, E M

    1989-06-01

    From the very beginning of physiological studies on the endocine pancreas, fish have been used as experimental subjects. Fish insulin was one of the first vertebrate insulins isolated and one of the first insulins whose primary and then tertiary structures were reported. Before a second pancreatic hormone, glucagon, was characterized, a physiologically active 'impurity', similar to that in mammalian insulin preparations, was found in fish insulins.Fish have become the most widely used model for studies of biosynthesis and processing of the pancreatic hormones. It seems inconceivable, therefore, that until the recent past cod and tuna insulins have been the only purified piscine islet hormones available for physiological experiments. The situation has changed remarkably during the last decade.In this review the contemporary status of physiological studies on the fish pancreas is outlined with an emphasis on the following topics: 1) contents of pancreatic peptides in plasma and in islet tissue; 2) actions of piscine pancreatic hormones in fish; 3) specific metabolic consequences of an acute insufficiency of pancreatic peptides; 4) functional interrelations among pancreatic peptides which differ from those of mammals. The pitfalls, lacunae and the perspectives of contemporary physiological studies on fish endocrine pancreas are outlined.

  17. A Fast-Starting Robotic Fish

    Science.gov (United States)

    Modarres-Sadeghi, Yahya; Watts, Matthew; Conte, Joe; Hover, Franz; Triantafyllou, Michael

    2009-11-01

    We have built a simple mechanical system to emulate the fast-start performance of fish. The system consisted of a thin metal beam covered by a urethane rubber fish body. The body form of the mechanical fish in this work was modeled from a pike species, which is the most successfully studied fast-start specialist species. The mechanical fish was held in curvature and hung in water by two restraining lines, which were simultaneously released by pneumatic cutting mechanisms. The potential energy in the beam was transferred into the fluid, thereby accelerating the fish, similar to a pike. We measured the resulting velocity and acceleration, as well as the efficiency of propulsion for the mechanical fish model and also ran a series of flow visualization tests to observe the resulting flow pattern. We also studied the influence of stiffness and geometry of the tail on the efficiency of propulsion and flow pattern. The hydrodynamic efficiency of the fish, calculated by the transfer of energy, was around 10%. Flow visualization of the mechanical fast-start wake was also analyzed, showing that the acceleration is associated with the fast movement of an intense vortex in a near-lateral direction.

  18. How to Represent a Fish?

    Directory of Open Access Journals (Sweden)

    Elspeth Probyn

    2017-05-01

    Full Text Available This article canvasses a broad range of fish representations across several disciplines. It asks what cultural studies can learn from scientific representation of fish, and argues that in turn cultural studies can be a nuanced understanding of the work of images. The objective of the article is to open debate about fish and their sustainability beyond discrete disciplines and/or ideologies. This, it is argued, is crucial if we are to go beyond a simplified cultural politics of fish.

  19. PARASITES OF FISH

    Science.gov (United States)

    The intent of this chapter is to describe the parasites of importance to fishes maintained and used in laboratory settings. In contrast to the frist edition, the focus will be only on those parasites that pose a serious threat to or are common in fishes held in these confined en...

  20. Management of Artisanal Fishing Port: a Case Study on Labuhanhaji Fishing Port, South Aceh Regency, Aceh Province

    OpenAIRE

    NurJannah, Betri; ', Syaifuddin; Zain, Jonny

    2014-01-01

    A series survey activity was carried out for evaluating management function atlabuanhaji fishing port, South Aceh regency. This research was emphasis on planning, organizing, action and controlling at management pattern of labuhanhaji fishing port. The facilities of fishing port data and daily activities description of staff at labuhanhaji fishing port was used as additional information and consideration in management of labuhanhaji fishing port. Lack of good management was impact on staff an...

  1. Fish welfare in capture fisheries

    NARCIS (Netherlands)

    Veldhuizen, L.J.L.; Berentsen, P.B.M.; Boer, de I.J.M.; Vis, van de J.W.; Bokkers, E.A.M.

    2018-01-01

    Concerns about the welfare of production animals have extended from farm animals to fish, but an overview of the impact of especially capture fisheries on fish welfare is lacking. This review provides a synthesis of 85 articles, which demonstrates that research interest in fish welfare in capture

  2. Reef fish communities in the central Red Sea show evidence of asymmetrical fishing pressure

    KAUST Repository

    Kattan, Alexander; Coker, Darren James; Berumen, Michael L.

    2017-01-01

    In order to assess human impacts and develop rational restoration goals for corals reefs, baseline estimates of fish communities are required. In Saudi Arabian waters of the Red Sea, widespread unregulated fishing is thought to have been ongoing for decades, but there is little direct evidence of the impact on reef communities. To contextualize this human influence, reef-associated fish assemblages on offshore reefs in Saudi Arabia and Sudan in the central Red Sea were investigated. These reefs have comparable benthic environments, experience similar oceanographic influences, and are separated by less than 300 km, offering an ideal comparison for identifying potential anthropogenic impacts such as fishing pressure. This is the first study to assess reef fish biomass in both these regions, providing important baselines estimates. We found that biomass of top predators on offshore Sudanese reefs was on average almost three times that measured on comparable reefs in Saudi Arabia. Biomass values from some of the most remote reefs surveyed in Sudan’s far southern region even approach those previously reported in the Northwestern Hawaiian Islands, northern Line Islands, Pitcairn Islands, and other isolated Pacific islands and atolls. The findings suggest that fishing pressure has significantly altered the fish community structure of Saudi Arabian Red Sea reefs, most conspicuously in the form of top predator removal. The results point towards the urgent need for enhanced regulation and enforcement of fishing practices in Saudi Arabia, while making a strong case for protection in the form of no-take marine protected areas to maintain preservation of the relatively intact southern Sudanese Red Sea.

  3. Reef fish communities in the central Red Sea show evidence of asymmetrical fishing pressure

    KAUST Repository

    Kattan, Alexander

    2017-03-09

    In order to assess human impacts and develop rational restoration goals for corals reefs, baseline estimates of fish communities are required. In Saudi Arabian waters of the Red Sea, widespread unregulated fishing is thought to have been ongoing for decades, but there is little direct evidence of the impact on reef communities. To contextualize this human influence, reef-associated fish assemblages on offshore reefs in Saudi Arabia and Sudan in the central Red Sea were investigated. These reefs have comparable benthic environments, experience similar oceanographic influences, and are separated by less than 300 km, offering an ideal comparison for identifying potential anthropogenic impacts such as fishing pressure. This is the first study to assess reef fish biomass in both these regions, providing important baselines estimates. We found that biomass of top predators on offshore Sudanese reefs was on average almost three times that measured on comparable reefs in Saudi Arabia. Biomass values from some of the most remote reefs surveyed in Sudan’s far southern region even approach those previously reported in the Northwestern Hawaiian Islands, northern Line Islands, Pitcairn Islands, and other isolated Pacific islands and atolls. The findings suggest that fishing pressure has significantly altered the fish community structure of Saudi Arabian Red Sea reefs, most conspicuously in the form of top predator removal. The results point towards the urgent need for enhanced regulation and enforcement of fishing practices in Saudi Arabia, while making a strong case for protection in the form of no-take marine protected areas to maintain preservation of the relatively intact southern Sudanese Red Sea.

  4. 2010 Great Lakes Human Health Fish Tissue Study Fish Tissue Data Dictionary

    Science.gov (United States)

    The Office of Science and Technology (OST) is providing the fish tissue results from the 2010 Great Lakes Human Health Fish Tissue Study (GLHHFTS). This document includes the “data dictionary” for Mercury, PFC, PBDE and PCBs.

  5. Otolith Length-Fish Length Relationships of Eleven US Arctic Fish Species and Their Application to Ice Seal Diet Studies

    Science.gov (United States)

    Walker, K. L.; Norcross, B.

    2016-02-01

    The Arctic ecosystem has moved into the spotlight of scientific research in recent years due to increased climate change and oil and gas exploration. Arctic fishes and Arctic marine mammals represent key parts of this ecosystem, with fish being a common part of ice seal diets in the Arctic. Determining sizes of fish consumed by ice seals is difficult because otoliths are often the only part left of the fish after digestion. Otolith length is known to be positively related to fish length. By developing species-specific otolith-body morphometric relationships for Arctic marine fishes, fish length can be determined for fish prey found in seal stomachs. Fish were collected during ice free months in the Beaufort and Chukchi seas 2009 - 2014, and the most prevalent species captured were chosen for analysis. Otoliths from eleven fish species from seven families were measured. All species had strong linear relationships between otolith length and fish total length. Nine species had coefficient of determination values over 0.75, indicating that most of the variability in the otolith to fish length relationship was explained by the linear regression. These relationships will be applied to otoliths found in stomachs of three species of ice seals (spotted Phoca largha, ringed Pusa hispida, and bearded Erignathus barbatus) and used to estimate fish total length at time of consumption. Fish lengths can in turn be used to calculate fish weight, enabling further investigation into ice seal energetic demands. This application will aid in understanding how ice seals interact with fish communities in the US Arctic and directly contribute to diet comparisons among and within ice seal species. A better understanding of predator-prey interactions in the US Arctic will aid in predicting how ice seal and fish species will adapt to a changing Arctic.

  6. Fish radurization on board of mediterranean fishing boats

    International Nuclear Information System (INIS)

    Leonardi, M.; Tata, A.

    1988-01-01

    The paper presents the results of a feasibility-study carrie out by ENEA with the technical support of ICRAP. Owing to its conclusions, the authors can locate some areas of possible application of fish-radurization both for the inner and for the foreign market. The former may offer in particular the opportunity of the on-board radurization, because of its peculiar characteristics. The latter may be particularly receptive in the case of those countries where refrigerating line is lacking and where the distribution of fresh fish-products seems rather difficult

  7. Fish & Wildlife Annual Project Summary, 1983.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1984-07-01

    BPA's Division of Fish and Wildlife was created in 1982 to develop, coordinate and manage BPA's fish and wildlife program. Division activities protect, mitigate, and enhance fish and wildlife resources impacted by hydroelectric development and operation in the Columbia River Basin. At present the Division spends 95% of its budget on restoration projects. In 1983, 83 projects addressed all aspects of the anadromous fish life cycle, non-migratory fish problems and the status of wildlife living near reservoirs.

  8. Monitoring translocations by M-FISH and three-color FISH painting techniques. A study of two radiotherapy patients

    International Nuclear Information System (INIS)

    Pouzoulet, F.; Roch-Lefevre, S.; Giraudet, AL.

    2007-01-01

    To compare translocation rate using either M-FISH or FISH-3 in two patients treated for head and neck cancer, with a view to retrospective dosimetry. Translocation analysis was performed on peripheral blood lymphocyte cultures from blood samples taken at different times during the radiotherapy (0 Gy, 12 Gy and 50 Gy) and a few months after the end of the treatment (follow-up). Estimated translocation yield varied according to the FISH technique used. At 50 Gy and follow-up points, the translocation yields were higher with FISH-3 than with M-FISH. This difference can be attributed to three events. First, an increase in complex aberrations was observed for 50 Gy and follow-up points compared with 0 Gy and 12 Gy points. Second, at the end of treatment for patient A, involvement of chromosomes 2, 4, 12 in translocations was less than expected according to the Lucas formula. Third, a clone bearing a translocation involving a FISH-3 painted chromosome was detected. More translocations were detected with M-FISH than with FISH-3, and so M-FISH is expected to improve the accuracy of chromosome aberration analyses in some situations. (author)

  9. Clostridium botulinum in irradiated fish

    International Nuclear Information System (INIS)

    Hobbs, G.

    1977-01-01

    The properties of the Cl. botulinum resp. its toxin are described with a view to a combined heat and radiation treatment for fish conservation. The method is tested in several laboratories on 10 different fish products. It is found that the spore former Cl. botulinum is a critical factor in this type of preservation which can hardly be overcome although this method has organoleptic advantages over heat pasteurization of fish. At a storage temperatue over 5 0 C, there is a strong increase in toxin; the same applies to fish with a high fat content. Under poor hygienic conditions, the risk is markedly increased. The author recommends strict control measures in the production and distribution of fish, i.e. cooling and salt treatment. (AJ) [de

  10. Impact of fishing on size composition and diversity of demersal fish communities

    DEFF Research Database (Denmark)

    Bianchi, G.; Gislason, Henrik; Graham, K.

    2000-01-01

    . but particularly in high-latitude regions, we observe a decreasing trend in the slope, reflecting changes in size composition toward a relative decline in larger fish. The results from tropical regions are less conclusive, partly owing to the difficulty in obtaining consistent data series, but probably also......By analysing data sets from different world regions we add evidence to documented changes in demersal fish community structure that may be related to fishing. Changes are analysed by community properties that might be expected to capture relevant overall changes - size spectra slopes and intercepts...... because the generally higher growth rates of the constituent species make the slope less sensitive to changes in fishing. No evidence was found of any decline in species richness, while changes in diversity (richness and evenness) were caused either by changes in patterns of dominance or by changes...

  11. Columbia River ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Columbia River. Vector polygons in this...

  12. Life histories of potamodromous fishes [Chapter 4

    Science.gov (United States)

    Russell F. Thurow

    2016-01-01

    Potamodromous fishes move and complete their life cycle entirely within freshwater. Myers (1949) proposed the term potamodromous to distinguish freshwater migratory fishes from diadromous fishes, which migrate between the sea and freshwater and oceanodromous fishes that migrate wholly within the sea. Diadromous fishes include anadromous, catadromous and amphidromous...

  13. Prevalence of fish diseases in fish farms in Katsina State, Nigeria ...

    African Journals Online (AJOL)

    Prevalence of fish disease in fish farms in Nigeria was investigated using data from structured questionnaire obtained during farm visits, and analysed using descriptive statistics and multiple linear regression. Findings from the study revealed that majority of the farm manager's (45.7) have less than 3 years of experience in ...

  14. Evaluation of Fish Passage Conditions for Juvenile Salmonids Using Sensor Fish at Detroit Dam, Oregon

    International Nuclear Information System (INIS)

    Duncan, Joanne P.

    2010-01-01

    Fish passage conditions through two spillways at Detroit Dam on the North Santiam River in Oregon were evaluated by Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers (USACE), Portland District, using Sensor Fish devices. The objective of the study was to describe and compare passage exposure conditions through Spillbay 3 and Spillbay 6 at 1.5- and 3.5-ft gate openings, identifying potential fish injury regions of the routes. The study was performed in July 2009, concurrent with HI-Z balloon-tag studies by Normandeau Associates, Inc. Sensor Fish and live fish were deployed at elevations approximately 3 ft above structure at depths determined using a computational fluid dynamics model. Data collected were analyzed to estimate (1) exposure conditions, particularly exposure to severe collision and shear events by passage route sub-regions; (2) differences in passage conditions between passage routes; and (3) relationships to live-fish injury and mortality data estimates.

  15. Possibilities of the fish pass restoration

    Science.gov (United States)

    Čubanová, Lea

    2018-03-01

    According to the new elaborated methodology of the Ministry of Environment of the Slovak Republic: Identification of the appropriate fish pass types according to water body typology (2015) each barrier on the river must be passable. On the barriers or structures without fish passes new ones should be design and built and on some water structures with existed but nonfunctional fish passes must be realized reconstruction or restoration of such objects. Assessment should be done in terms of the existing migratory fish fauna and hydraulic conditions. Fish fauna requirements resulting from the ichthyological research of the river section with barrier. Hydraulic conditions must than fulfil these requirements inside the fish pass body.

  16. Response of PCB contamination in stream fish to abatement actions at an industrial site

    International Nuclear Information System (INIS)

    Southworth, G.R.; Peterson, M.J.; McCarthy, J.F.; Milne, G.

    1995-01-01

    The Paducah Gaseous Diffusion Plant (PGDP) in Paducah, Kentucky, used large quantities of PCBs in equipment associated with the great electric power requirements of isotopic enrichment of uranium. Historic losses of PCBs in the 1950s and 1960s have left a legacy of contamination at the site. A biological monitoring program implemented in 1987 found PCBs in PGDP effluents and in fish downstream from facility discharges. As a consequence, a fish consumption advisory was posted on Little Bayou Creek by the Commonwealth of Kentucky in 1987, and regulatory discharge limits for PCBs at PGDP were reduced. Monitoring at multiple locations in receiving streams indicated that PGDP discharges were more important than in stream sediment contamination as sources of PCBs to fish. Environmental management and compliance staff at PGDP led an effort to reduce PCB discharges and monitor the effects of those actions. The active discharge of uncontaminated process water to historically PCB-contaminated drainage systems was found to mobilize PCBs into KPDES (Clean Water Act) regulated effluents. Efforts to locate PCB sources within the plant, coupled with improvements in management practices and remedial actions, appear to have been successful in reducing PCB discharges from these sources. Actions included emplacing passive monitors in the plant drainage system to identify this as a chronic source, and consolidating and re-routing effluents to minimize flow through PCB-contaminated channels. As a consequence, PCB contamination in fish in small streams receiving plant discharges decreased 75% over from 1992--1995

  17. Western Alaska ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and anadromous fish species in Western Alaska. Vector polygons in this data set...

  18. Impacts of fishing and environmental factors driving changes on littoral fish assemblages in a subtropical oceanic island

    Science.gov (United States)

    Sangil, Carlos; Martín-García, Laura; Hernández, José Carlos; Concepción, Laura; Fernández, Raúl; Clemente, Sabrina

    2013-08-01

    The structure of demersal fish assemblages of commercial interest was studied at 51 sites on La Palma Island (Canary Islands, northeastern Atlantic). On this island, demersal fish populations are limited and independent from other islands. As deep water separates the islands and the shallow sublittoral platforms are not continuous, adult inter-island migrations are not possible except between the islands of Lanzarote and Fuerteventura. Otherwise, each island functions as a closed system, and the status of an island fish assemblage depends on local environmental conditions and activities performed in situ by the islanders. These circumstances provide a unique opportunity to test the intrainsular variability of fish assemblages. With this background, environmental parameters, fishing pressure and distance to the MPA were considered to identify the main factors explaining the spatial variation of fish assemblages off La Palma Island. Twenty-six fish species were recorded, but 60% of the total fish biomass was represented by only five species (Sparisoma cretense, Pomadasys incisus, Canthidermis sufflamen, Diplodus cervinus cervinus and Bodianus scrofa). However, the structure of assemblages was heterogeneous in response to different variables and showed substantial spatial variation. The assemblages were strongly modified by the presence of upright seaweed cover, fishing activities, and certain environmental variables. Differences were more pronounced in species that occupied the higher trophic levels. The most disturbed assemblages were those located in areas with lower upright seaweed cover and with higher fishing pressure, whereas the best-preserved assemblages corresponded to sites with controlled fishing activities, located within the MPA.

  19. Fishing fleet profiling methodology

    National Research Council Canada - National Science Library

    Ferraris, Jocelyne

    2002-01-01

    A fishing fleet profile aims tho assist in understanding the complexity and structure of fisheries from a technical and socio-economic point of view, or from the point of view of fishing strategies...

  20. Contents of radionuclides and heavy metals in fish roe of commercial fish of the Zaporizhya reservoir

    International Nuclear Information System (INIS)

    Belokon', A.S.; Marenkov, O.N.; Dvoretskij, A.I.

    2013-01-01

    Comprehensive radiation-toxicological studies of fish roe of some commercial fish of the Zaporizhya Reservoir were conducted. It was found that the greatest number of 137 Cs (4,5 Bq/kg) and 90 Sr (3,2 Bq/kg) was accumulated by fish roe of perch. Heavy metals (cadmium, copper, zinc and lead), and natural radionuclides 226 Ra and 232 Th were accumulated to a greater amount of bream fish roe

  1. Freshwater fishes of Tsitsikamma National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2002-12-01

    Full Text Available This study aimed to determine the distribution and relative abundance of freshwater fishes in the Tsitsikamma National Park. Fish assemblages in six river systems were sampled in 2001, with a total of 323 fish from eight species recorded. Indigenous fish collected included four freshwater species (Pseudobarbus afer, Pseudobarbus tenuis, Sandelia capensis, Anguilla mossambica, three estuarine species (Monodactylus falciformis, Caffrogobius gilchristi, Myxus capensis, and one alien (Micropterus salmoides. One additional indigenous species (Galaxias zebratus and two aliens (Salmo trutta, Oncorhynchus mykiss could potentially occur within the park. The topography and locality of the park presents a unique opportunity to meaningfully conserve the endangered P. tenuis as well as other fish characteristic of the eastern reaches of the Cape Floristic Region. Management action is required to minimise opportunities for further establishment and spread of alien fish species and to conserve indigenous fish assemblages within the park.

  2. Area-based management and fishing efficiency

    DEFF Research Database (Denmark)

    Marchal, P.; Ulrich, Clara; Pastoors, M.

    2002-01-01

    The scope of this study is to investigate the extent to which area-based management may have influenced the fishing efficiency of the Danish and Dutch demersal fleets harvesting cod, plaice and sole in the North Sea. Special consideration is given to the 'plaice box', a restricted area where...... fishing is prohibited to towed-gear fleets of horsepower exceeding 300 hp. An index of fishing power is calculated as the log-ratio between the catch per unit effort (CPUE) of any vessel and some survey abundance index. Annual trends in fishing are calculated as the year-effect derived from a general...... linear model (GLM) analysis of the index of fishing power. The fishing efficiency of Danish gill-netters and, to some extent, Danish seiners, has overall increased inside the 'plaice box', whilst remaining relatively stable outside. However, the fishing efficiency of the other exemption fleets has...

  3. Fish allergens at a glance: Variable allergenicity of parvalbumins, the major fish allergens

    OpenAIRE

    Annette eKuehn; Ines eSwoboda; Karthik eArumugam; Christiane eHilger; François eHentges; François eHentges

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand,...

  4. Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens

    OpenAIRE

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand,...

  5. Phylogenetic classification of bony fishes.

    Science.gov (United States)

    Betancur-R, Ricardo; Wiley, Edward O; Arratia, Gloria; Acero, Arturo; Bailly, Nicolas; Miya, Masaki; Lecointre, Guillaume; Ortí, Guillermo

    2017-07-06

    Fish classifications, as those of most other taxonomic groups, are being transformed drastically as new molecular phylogenies provide support for natural groups that were unanticipated by previous studies. A brief review of the main criteria used by ichthyologists to define their classifications during the last 50 years, however, reveals slow progress towards using an explicit phylogenetic framework. Instead, the trend has been to rely, in varying degrees, on deep-rooted anatomical concepts and authority, often mixing taxa with explicit phylogenetic support with arbitrary groupings. Two leading sources in ichthyology frequently used for fish classifications (JS Nelson's volumes of Fishes of the World and W. Eschmeyer's Catalog of Fishes) fail to adopt a global phylogenetic framework despite much recent progress made towards the resolution of the fish Tree of Life. The first explicit phylogenetic classification of bony fishes was published in 2013, based on a comprehensive molecular phylogeny ( www.deepfin.org ). We here update the first version of that classification by incorporating the most recent phylogenetic results. The updated classification presented here is based on phylogenies inferred using molecular and genomic data for nearly 2000 fishes. A total of 72 orders (and 79 suborders) are recognized in this version, compared with 66 orders in version 1. The phylogeny resolves placement of 410 families, or ~80% of the total of 514 families of bony fishes currently recognized. The ordinal status of 30 percomorph families included in this study, however, remains uncertain (incertae sedis in the series Carangaria, Ovalentaria, or Eupercaria). Comments to support taxonomic decisions and comparisons with conflicting taxonomic groups proposed by others are presented. We also highlight cases were morphological support exist for the groups being classified. This version of the phylogenetic classification of bony fishes is substantially improved, providing resolution

  6. Ocular media transmission of coral reef fish--can coral reef fish see ultraviolet light?

    Science.gov (United States)

    Siebeck, U E; Marshall, N J

    2001-01-15

    Many coral reef fish are beautifully coloured and the reflectance spectra of their colour patterns may include UVa wavelengths (315-400 nm) that are largely invisible to the human eye (Losey, G. S., Cronin, T. W., Goldsmith, T. H., David, H., Marshall, N. J., & McFarland, W.N. (1999). The uv visual world of fishes: a review. Journal of Fish Biology, 54, 921-943; Marshall, N. J. & Oberwinkler, J. (1999). The colourful world of the mantis shrimp. Nature, 401, 873-874). Before the possible functional significance of UV patterns can be investigated, it is of course essential to establish whether coral reef fishes can see ultraviolet light. As a means of tackling this question, in this study the transmittance of the ocular media of 211 coral reef fish species was measured. It was found that the ocular media of 50.2% of the examined species strongly absorb light of wavelengths below 400 nm, which makes the perception of UV in these fish very unlikely. The remaining 49.8% of the species studied possess ocular media that do transmit UV light, making the perception of UV possible.

  7. Southeast Alaska ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for estuarine, benthic, and pelagic fish in Southeast Alaska. Vector polygons in this data set represent locations of...

  8. Discharge residence of TLD tagged fish

    International Nuclear Information System (INIS)

    Romberg, G.P.; Prepejchal, W.

    1974-01-01

    Although visual observations suggested that fish remained in the discharge for considerable periods, temperature-sensitive tags indicated the majority of fish spend less than 50 hr or 10 percent of the time at discharge temperatures. During 1974 a second fish tagging study was conducted, using temperature-sensitive tags to yield discharge residence times of Lake Michigan salmonids at Point Beach thermal discharge. Preliminary results revealed that many fish tag values were close to Unit I line indicating that calculated maximum discharge residence times for these fish will be nearly 100 percent of the elapsed time

  9. Intake of mercury through fish consumption

    International Nuclear Information System (INIS)

    Sarmani, S.B.; Kiprawi, A.Z.; Ismail, R.B.; Hassan, R.B.; Wood, A.K.; Rahman, S.A.

    1995-01-01

    Fish has been known as a source of non-occupational mercury exposure to fish consuming population groups, and this is shown by the high hair mercury levels. In this study, hair samples collected from fishermen and their families, and commercial marine fishes were analyzed for mercury and methylmercury by neutron activation and gas chromatography. The results showed a correlation between hair mercury levels and fish consumption patterns. The levels of mercury found in this study were similar to those reported by other workers for fish consuming population groups worldwide. (author)

  10. Do Fish Enhance Tank Mixing?

    DEFF Research Database (Denmark)

    Rasmussen, Michael R.; Laursen, Jesper; Craig, Steven R.

    2005-01-01

    The design of fish rearing tanks represents a critical stage in the development of optimal aquaculture systems, especially in the context of recirculating systems. Poor hydrodynamics can compromise water quality, waste management and the physiology and behaviour of fish, and thence, production...... potential and operational profitability. The hydrodynamic performance of tanks, therefore, represents an important parameter during the tank design process. Because there are significant complexities in combining the rigid principles of hydrodynamics with the stochastic behaviour of fish, however, most data...... upon tank hydrokinetics has been derived using tanks void of fish. Clearly, the presence of randomly moving objects, such as fish, in a water column will influence not only tank volumes by displacing water, but due to their activity, water dynamics and associated in-tank processes. In order...

  11. The role of middlemen in fish marketing in Igbokoda fish market, Ondo-state, south western Nigeria

    Directory of Open Access Journals (Sweden)

    F.O. Agbebi

    2012-12-01

    Full Text Available The study on the role of middlemen in fish marketing was carried out in Igbokoda fish market in Ondo State, Nigeria with the use of structured questionnaire and personal interview to know the various activities in the fishing community and to be able to examine the socio-economic activities and characteristics of the fish marketers, the challenges in the market, the marketing procedures, the role middlemen plays and structures encountered in the fish business using descriptive analysis, such as the use of table, frequency, counts, mean and percentage. From this study, it was discovered that majority (42% of the respondents were within the age group of 31-40 years, thus indicating that most of them are within the economically active population. Majority of the marketers were involved in co-operative societies while only 10% were not involved in any co-operative society, which on the other hand indicate high level of rural poverty in the fishing community. 35% of the respondents have only one middleman, 22% have 2 middlemen and 38% of the respondents have 3 middlemen which indicate that their profit margin reduced as the number of middlemen increased. Fish sales in bulk and unit were observed in the area. Fish marketing, challenges and benefits that can be derived from it was also considered as well as facilities as a way of strengthening fish marketing structure by improving the bargaining power of traders and increasing the profit margin.

  12. Comparing demersal fish assemblage between periods of contrasting climate and fishing pressure

    NARCIS (Netherlands)

    Hofstede, ter R.; Rijnsdorp, A.D.

    2011-01-01

    Fish communities are dynamic and their structure is known to change over time. Traditionally, these changes were considered to be fisheries-induced, but recent analyses also suggest that global warming could affect the distribution, abundance, and assemblage composition of marine fish. However,

  13. Impact of using raw or fermented manure as fish feed on microbial quality of water and fish

    Directory of Open Access Journals (Sweden)

    Nagham Elsaidy

    2015-01-01

    Full Text Available The microbial water and fish quality was assessed due to feeding of chicken manure (CM and fermented chicken manure (FCM to fish in ponds, using Nile tilapia (Oreochromis niloticus which were classified into 7 groups (G. Each group received different mixtures of CM or FCM with fish ration (FR, 0:100, 25:75, 50:50 and 100:0 (%CM or FCM:% FR. The obtained results revealed that total bacterial count (TBC and total coliform count (TCC were significantly high at P ⩽ 0.05 in CM than both FCM and fish ration (FR. Escherichia coli and Salmonella were isolated from CM but not from FCM or FR. Additionally, TBC and TCC were significantly high at P ⩽ 0.05 at water and fish samples raised at CM ponds followed by FCM ponds in comparison with FR. Both E. coli and Salmonella were isolated from water and fish raised in ponds receiving either CM or FCM with higher incidence in those with CM. However all water and fish samples examined were free from E-coli O157: H7. The obtained results, proved the influence of CM on water and fish quality and recommend the use of FCM as a bacteriologically safe fish pond fertilizer.

  14. 50 CFR 622.38 - Landing fish intact.

    Science.gov (United States)

    2010-10-01

    ... that is operating under the respective trip limits. Such cut-off fish also may be sold. A maximum of... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Landing fish intact. 622.38 Section 622.38... Landing fish intact. The operator of a vessel that fishes in the EEZ is responsible for ensuring that fish...

  15. Production of Fish Hydrolysates Protein From Waste of Fish Carp (Cyprinus Carpio by Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Dede Saputra

    2016-03-01

    Full Text Available Fish Protein Hydrolysates (FPH is the mixed products of polypeptide, dipeptides, and amino acid. It can be produced from materials that contained of protein by acid reaction, base reaction or enzymatic hydrolysis. The objectives of this study were to study the production of FPH from fish carp meat at post rigor phase and viscera by enzymatic hydrolysis, to determine the specific activity of papain enzyme, and to determine the solubility of FPH. Capacity of fish hydrolyzing can be identified by analyzing the content of dissolved total nitrogen (NTT compared with nitrogen total ingredient (NTB in order to get the value of total soluble nitrogen/total nitrogen material (NTT/NTB. The hydrolysis processes were carried out in 0,26% (w/v papain, 60 οC for 3 hours. The result showed that the specific activity of papain enzyme was about 3.28 U/mg. Solubility of FPH by comparing NTT/NTB was about 0.29% (fish meat and 0.40% (fish viscera. Proximate test of protein content of fish meat was 18.34 ± 0.04 (g/100 g; while viscera was about 0.95±0.04 (g/100 g. The result indicated that product waste of fish carp had potential as a major of source of FPH.

  16. Hawaiian Fish Distributors Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is proprietary sales data from one Kona-based fish dealer for August 1986 to Decemeber 1988. Fishing was generally around Kona. This is Dealer Data and is...

  17. The impact on the fishing industry

    International Nuclear Information System (INIS)

    Buchan, G.; Allan, R.

    1992-01-01

    When the first signs of the oil boom manifested themselves on the Scottish business and community scene in the early 1970's those in the fishing industry in particular had no idea of the magnitude of the impact that it would have on their way of life or the manner in which they had traditionally earned their living. Some 20 years on from that emerging scenario, the reality must e faced that the fishing industry has a very formidable and still growing competitor in the North Sea, which has at times threatened to overwhelm fishing, in terms of its sheer technical, economic and political muscle and know-how. This chapter examines the individual aspects of the interaction between the fishing industry and the oil resource development process that contribute to the overall impact. These include: lack of consultation with the fishing industry by the government when granting exploration licences; the location of platforms, drilling rigs, subsea installations and suspended well-heads; damage occurring when fishing gear makes contact with pipelines lying proud on the seabed in traditional fishing grounds; the amount of debris dumped by the oil and gas industry; economic loss suffered by the fishing industry as a result of its exclusion from many traditional areas; concern over decommissioned and abandoned off-shore installations. Nevertheless, it is acknowledged that the fishing industry has derived significant benefits from the presence of the oil industry in the North Sea, particularly from the readiness of platform personnel to respond to needs and emergencies on any fishing vessels. (UK)

  18. Additive and Synergistic Impacts of Fishing and Warming on the Growth of a Temperate Marine Fish

    Science.gov (United States)

    Morrongiello, J.

    2016-02-01

    Fishing and climate change are having profound impacts on the trajectory and variability of marine populations. However, despite the wealth of work undertaken in marine environments on the causes of longer-term biological change, the effects of these two drivers have traditionally been considered in isolation or just additively. Such an approach obviously overlooks the potential for significant synergistic or antagonistic interactions between fishing and climate to occur. Indeed, it is increasingly becoming acknowledged that the direction and magnitude of biological responses to natural environmental variation and climate change can be mediated by other anthropogenic disturbances such as fishing, and vice versa. Somatic growth is an ideal candidate with which to explore the impacts of fishing and environmental variability due to its strong biological relevance and its heightened sensitivity to natural and anthropogenic drivers. I developed 19-year growth biochronologies (1980-1999) for three south-east Australian populations of a site-attached temperate reef fish, purple wrasse (Notolabrus fucicola) using individual-based growth information naturally archived in otoliths. A commercial wrasse fishery began in the early 1990s; before this there was negligible recreational or commercial fishing. The growth of older fish was proportionally higher and that of the youngest fish proportionally lower after the onset of commercial fishing; 2-year olds grew 7.4% slower, but 5-year-olds grew 10.3% and 10-year-olds 26% faster in the latter period. These results are consistent with a density dependent response to harvesting. Average growth rates across all ages increased by 6.6%.oC-1, reflecting either a direct or indirect temperature effect in this global marine 'hotspot'. Finally, the distribution of individual thermal reaction norms significantly changed post fishing, showing that fishing and temperature can have a synergetic impact on marine populations via within

  19. Snapshots of past fish faunas

    DEFF Research Database (Denmark)

    Enghoff, Inge Bødker; Ediger, Vedat

    2016-01-01

    Analyses of fish remains from sediment cores make it possible to detect not only commonly caught fish from prehistoric times, but also species without any economic importance, but with high value of paleaoecological reconstructions. In this study, fish bones from sediment cores reaching several...... thousand years back and taken in the Baltic and Black Seas were analysed. All fish remains dealt with postdate the last glaciations and are from the last marine/brackish stages of both seas. In the Baltic cores, 13+ species were found, the most abundant ones being sand-eel and clupeids (herring and sprat...... before industrial fishing for them began. Clupeids, in the Baltic samples also sand-eel, dominate the materials. Both contain species that would hardly be expected on archaeological sites. Experience from this study leads to methodological recommendations regarding dating of material from sediment cores...

  20. An overview of the ongoing insights in selenium research and its role in fish nutrition and fish health.

    Science.gov (United States)

    Khan, Kifayat Ullah; Zuberi, Amina; Fernandes, João Batista Kochenborger; Ullah, Imdad; Sarwar, Huda

    2017-12-01

    In the present review, the ongoing researches about selenium research in fish nutrition have been comprehensively discussed. Selenium research is getting popularity in fish nutrition as it is required for the normal growth and proper physiological and biochemical functions in fish. Its deficiency or surplus amounts create severe problems in fish. It is available as inorganic form, organic form, and nano form. In fish, most of the previous research is about the selenium requirements for fish by using only one selenium source mainly the inorganic one. Selenium shows maximum biological activity and bioavailability when it is supplied in proper form. However, to differentiate the more bioavailable and less toxic form of selenium, sufficient information is needed about the comparative bioavailability of different selenium forms in different fish species. In fish, important data about the new forms of selenoproteins is still scarce. Therefore, it is necessary to focus on the determination and elucidation of the new selenoproteins in fish through the utilization of recent approaches of molecular biology and proteomics. The adaptation of these new approaches will replace the old fashioned methodologies regarding the selenium research in fish nutrition. Moreover, the use of molecular biology and proteomics-based new approaches in combination with selenium research will help in optimizing the area of fish nutrition and will improve the feed intake, growth performance, and more importantly the flesh quality which has a promising importance in the consumer market.

  1. 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.

  2. Examination of the Fish Price Offered for Sale During 2012-2013 Fishing Season in Sinop, Turkey

    Directory of Open Access Journals (Sweden)

    Şennan Yücel

    2017-10-01

    Full Text Available The aim of the study was to determine the monthly price distribution of the offered fish species for sale within the scope of information received from the centers engaged in the sale of retail fish during 2012-2013 fishing season in Sinop, Turkey. The enterprises were grouped as I (the most, II (middle and III (the least according to the sales volume and fish species. Each group was represented by two different fish enterprise and so a total of six separate enterprises were determined by purpose sampling method. During the study, sale prices and fish species were obtained twice every month at the same time of day. It was determined that anchovy (Engraulis encrasicolus ponticus, horse mackerel (Trachurus trachurus, bluefish (Pomatomus saltatrix, atlantic bonito (Sarda sarda, twait shad (Alosa fallax nilotica, needlefish (Belone belone, mullet (Mugil cephalus, shi drum (Umbrina cirrosa, brown meagre (Sciana umbra, common two-banded seabream (Diplodus vulgaris, annular bream (Diplodus annularis, tub gurnard (Trigla lucerna, picarel (Maena smaris, turbot (Psetta maxima, red mullet (Mullus barbatus, whiting (Merlangus merlangus, scorpion fish (Scorpaena porcus, goby (Gobius niger were offered for sale in fish markets. While the prices of higher economic valued fish species like anchovy, bluefish, atlantic bonito and turbot prices were different between the enterprises, the prices of horse mackerel, red mullet and whiting species were not different. When considering the fish prices based on years, the prices of horse mackerel, bluefish, atlantic bonito, red mullet and haddock during 2012-2013 years were close to the average price of 2008-2012 years and the prices of anchovy and turbot during 2012-2013 years were higher than the average price of 2008-2012 years in Sinop.

  3. Life history variation in Barents Sea fish: implications for sensitivity to fishing in a changing environment.

    Science.gov (United States)

    Wiedmann, Magnus A; Primicerio, Raul; Dolgov, Andrey; Ottesen, Camilla A M; Aschan, Michaela

    2014-09-01

    Under exploitation and environmental change, it is essential to assess the sensitivity and vulnerability of marine ecosystems to such stress. A species' response to stress depends on its life history. Sensitivity to harvesting is related to the life history "fast-slow" continuum, where "slow" species (i.e., large, long lived, and late maturing) are expected to be more sensitive to fishing than "fast" ones. We analyze life history traits variation for all common fish species in the Barents Sea and rank fishes along fast-slow gradients obtained by ordination analyses. In addition, we integrate species' fast-slow ranks with ecosystem survey data for the period 2004-2009, to assess life history variation at the community level in space and time. Arctic fishes were smaller, had shorter life spans, earlier maturation, larger offspring, and lower fecundity than boreal ones. Arctic fishes could thus be considered faster than the boreal species, even when body size was corrected for. Phylogenetically related species possessed similar life histories. Early in the study period, we found a strong spatial gradient, where members of fish assemblages in the southwestern Barents Sea displayed slower life histories than in the northeast. However, in later, warmer years, the gradient weakened caused by a northward movement of boreal species. As a consequence, the northeast experienced increasing proportions of slower fish species. This study is a step toward integrating life history traits in ecosystem-based areal management. On the basis of life history traits, we assess the fish sensitivity to fishing, at the species and community level. We show that climate warming promotes a borealization of fish assemblages in the northeast, associated with slower life histories in that area. The biology of Arctic species is still poorly known, and boreal species that now establish in the Arctic are fishery sensitive, which calls for cautious ecosystem management of these areas.

  4. Immunity to fish rhabdoviruses

    Science.gov (United States)

    Purcell, Maureen K.; Laing, Kerry J.; Winton, James R.

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN) system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M) protein to mediate host-cell shutoff and the non-virion (NV) protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  5. Fish robotics and hydrodynamics

    Science.gov (United States)

    Lauder, George

    2010-11-01

    Studying the fluid dynamics of locomotion in freely-swimming fishes is challenging due to difficulties in controlling fish behavior. To provide better control over fish-like propulsive systems we have constructed a variety of fish-like robotic test platforms that range from highly biomimetic models of fins, to simple physical models of body movements during aquatic locomotion. First, we have constructed a series of biorobotic models of fish pectoral fins with 5 fin rays that allow detailed study of fin motion, forces, and fluid dynamics associated with fin-based locomotion. We find that by tuning fin ray stiffness and the imposed motion program we can produce thrust both on the fin outstroke and instroke. Second, we are using a robotic flapping foil system to study the self-propulsion of flexible plastic foils of varying stiffness, length, and trailing edge shape as a means of investigating the fluid dynamic effect of simple changes in the properties of undulating bodies moving through water. We find unexpected non-linear stiffness-dependent effects of changing foil length on self-propelled speed, and as well as significant effects of trailing edge shape on foil swimming speed.

  6. Immunity to fish rhabdoviruses.

    Science.gov (United States)

    Purcell, Maureen K; Laing, Kerry J; Winton, James R

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN) system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M) protein to mediate host-cell shutoff and the non‑virion (NV) protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  7. Immunity to Fish Rhabdoviruses

    Directory of Open Access Journals (Sweden)

    Maureen K. Purcell

    2012-01-01

    Full Text Available Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M protein to mediate host-cell shutoff and the non‑virion (NV protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  8. Monitoring fish distributions along electrofishing segments

    Science.gov (United States)

    Miranda, Leandro E.

    2014-01-01

    Electrofishing is widely used to monitor fish species composition and relative abundance in streams and lakes. According to standard protocols, multiple segments are selected in a body of water to monitor population relative abundance as the ratio of total catch to total sampling effort. The standard protocol provides an assessment of fish distribution at a macrohabitat scale among segments, but not within segments. An ancillary protocol was developed for assessing fish distribution at a finer scale within electrofishing segments. The ancillary protocol was used to estimate spacing, dispersion, and association of two species along shore segments in two local reservoirs. The added information provided by the ancillary protocol may be useful for assessing fish distribution relative to fish of the same species, to fish of different species, and to environmental or habitat characteristics.

  9. [Food hygiene aspects in the production of food fish in fishing].

    Science.gov (United States)

    Hörmansdorfer, S; Brand, U; Stein, H; Bauer, J

    1997-03-01

    The development of the aerob-mesophilic bacteria on epidermis and peritoneum of 68 barbels was determined at 0, 4 and 8 hours after slaughtering. Therefore, one group of 34 animals was stored at 15.3 degrees C, an other equal one at 21.6 degrees C. A change in germ counts per cm2 could be seen in none of the groups during the first 4 hours. However, unrefrigerated carcasses showed an increase of bacteria up to 5-fold between the 4th and 8th hour, whereas in the refrigerated group no change occurred during that time, too. Rinsing the fish after slaughtering resulted in a decrease of the initial bacterial counts by up to 65.4% and so in significantly lower germ loads at the end of the storage time. These results were confirmed by contaminating 24 rainbow trout with Salmonella Infantis artificially. The frequency of detection did not change in refrigerated fish over 8 hours, while nearly doubling in unrefrigerated ones. Moreover, it could be shown that a Salmonella-concentration of only 30 CFU per 100 ml water was sufficient for contaminating fish in detectable grades. The study leads to the conclusion that the storage of instantly slaughtered fish in a common thermobox with freezing elements is suited for preserving its microbiological status for at least 8 hours. The caging of living fish after capture, which must be regarded critically under the aspect of treating animals in a humane way, seems therefore unnecessary.

  10. Climate Change and Fish Availability

    Science.gov (United States)

    Teng, Paul P. S.; Lassa, Jonatan; Caballero-Anthony, Mely

    Human consumption of fish has been trending upwards in the past decades and this is projected to continue. The main sources of fish are from wild fisheries (marine and freshwater) and aquaculture. Climate change is anticipated to affect the availability of fish through its effect on these two sources as well as on supply chain processes such as storage, transport, processing and retail. Climate change is known to result in warmer and more acid oceans. Ocean acidification due to higher CO2 concentration levels at sea modifies the distribution of phytoplankton and zooplankton to affect wild, capture fisheries. Higher temperature causes warm-water coral reefs to respond with species replacement and bleaching, leading to coral cover loss and habitat loss. Global changes in climatic systems may also cause fish invasion, extinction and turnover. While this may be catastrophic for small scale fish farming in poor tropical communities, there are also potential effects on animal protein supply shifts at local and global scales with food security consequences. This paper discusses the potential impacts of climate change on fisheries and aquaculture in the Asian Pacific region, with special emphasis on Southeast Asia. The key question to be addressed is “What are the impacts of global climate change on global fish harvests and what does it mean to the availability of fish?”

  11. Invasion of parasitic isopods in marine fishes

    Directory of Open Access Journals (Sweden)

    Ganapathy Rameshkumar

    2013-02-01

    Full Text Available Objective: To carry out a detailed three-year observation study on isopod parasites infestation in fish. Methods: Fish samples were collected from different localities in various landing centers along the Tamil Nadu coastal area. The prevalence and mean intensity were calculated. The proximate composition of infestation and uninfestation were studied in different marine fishes. A comparative analysis of bacteria and fungi in the infected and uninfected regions of fishes were analysed. Results: Tweenty six species including 12 genera of isopods (Cymothoidae distributed in 39 species of marine fishes along the Tamil Nadu coast. The isopod parasites were attached in three different microhabitats in host fishes viz. , buccal, branchial and body surfaces. They exhibited host and site specific occurrence. Maximum prevalence 17.11% was recorded in March 2010 and minimum 0.27% in Febuary 2010. The intensity ranged from 1 to 1.7 parasites per fish during the different months from Decmber 2008 to November 2011. There was a decrease in the protein, carbohydrate and lipid content in the infested fishes compared to uninfected fishes. A comparative analysis of bacteria and fungi in the infected and uninfected region of fishes were analysed. It revealed that infected portions had dense bacterial load as observed in the lesions of infected fishes than uninfected fishes. Conclusion: Factors which are able to induce parasitic manifestation are stock quality, stocking density, environmental conditions, biological and physiological characteristics of parasite, zoo technical measures, food quantity, feeding strategies, etc.

  12. Colville Tribal Fish Hatchery, 2000-2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Arteburn, John; Christensen, David (Colville Confederated Tribes, Nespelem, WA)

    2003-03-01

    Federal hydropower projects as well as private power utility systems have had a devastating impact upon anadromous fish resources that once flourished in the Columbia River and it's tributaries. Several areas were completely blocked to anadromous fish by dams, causing the native people who's number one food resource was salmon to rely entirely upon resident fish to replace lost fisheries resources. The Colville Tribal Fish Hatchery is an artificial production program to partially mitigate for anadromous fish losses in the ''Blocked Area'' above Chief Joseph and Grand Coulee Dams pursuant to Resident Fish Substitution Policy of the Northwest Power Planning Councils Fish and Wildlife Program. The hatchery was accepted into the Council's Fish and Wildlife Program in 1984 as a resident fish substitution measure and the hatchery was completed in 1990. The minimum production quota for this facility is 22,679 kg (50,000 lbs.) of trout. To achieve this quota the Colville Tribal Hatchery was scheduled to produce 174,000 fingerling rainbow trout (5 grams/fish), 330,000 sub-yearling rainbow trout (15 grams/fish), 80,000 legal size rainbow trout (90 grams/fish), 196,000 fingerling brook trout (5 grams/fish), 330,000 subyearling brook trout (15 grams/fish) and 60,000 lahontan cutthroat trout (15 grams/fish) in 2001. All fish produced are released into reservation waters, including boundary waters in an effort to provide a successful subsistence /recreational fishery for Colville Tribal members as well as a successful non-member sport fishery. The majority of the fish distributed from the facility are intended to provide a ''carry-over'' fishery. Fish produced at the facility are intended to be capable of contributing to the natural production component of the reservation fish populations. Contribution to the natural production component will be achieved by producing and releasing fish of sufficient quality and quantity for

  13. Guidelines for Eating Fish that Contain Mercury

    Science.gov (United States)

    Learn about how to minimize exposure to methylmercury while eating fish. Read about fish advisories, how to use them to consume fish safely, and use the national fish advisories locator to find them in an area near you.

  14. Finding NEMO (novel electromaterial muscle oscillator): a polypyrrole powered robotic fish with real-time wireless speed and directional control

    International Nuclear Information System (INIS)

    McGovern, Scott; Alici, Gursel; Spinks, Geoffrey; Truong, Van-Tan

    2009-01-01

    This paper presents the development of an autonomously powered and controlled robotic fish that incorporates an active flexural joint tail fin, activated through conducting polymer actuators based on polypyrrole (PPy). The novel electromaterial muscle oscillator (NEMO) tail fin assembly on the fish could be controlled wirelessly in real time by varying the frequency and duty cycle of the voltage signal supplied to the PPy bending-type actuators. Directional control was achieved by altering the duty cycle of the voltage input to the NEMO tail fin, which shifted the axis of oscillation and enabled turning of the robotic fish. At low speeds, the robotic fish had a turning circle as small as 15 cm (or 1.1 body lengths) in radius. The highest speed of the fish robot was estimated to be approximately 33 mm s −1 (or 0.25 body lengths s −1 ) and was achieved with a flapping frequency of 0.6–0.8 Hz which also corresponded with the most hydrodynamically efficient mode for tail fin operation. This speed is approximately ten times faster than those for any previously reported artificial muscle based device that also offers real-time speed and directional control. This study contributes to previously published studies on bio-inspired functional devices, demonstrating that electroactive polymer actuators can be real alternatives to conventional means of actuation such as electric motors

  15. Finding NEMO (novel electromaterial muscle oscillator): a polypyrrole powered robotic fish with real-time wireless speed and directional control

    Science.gov (United States)

    McGovern, Scott; Alici, Gursel; Truong, Van-Tan; Spinks, Geoffrey

    2009-09-01

    This paper presents the development of an autonomously powered and controlled robotic fish that incorporates an active flexural joint tail fin, activated through conducting polymer actuators based on polypyrrole (PPy). The novel electromaterial muscle oscillator (NEMO) tail fin assembly on the fish could be controlled wirelessly in real time by varying the frequency and duty cycle of the voltage signal supplied to the PPy bending-type actuators. Directional control was achieved by altering the duty cycle of the voltage input to the NEMO tail fin, which shifted the axis of oscillation and enabled turning of the robotic fish. At low speeds, the robotic fish had a turning circle as small as 15 cm (or 1.1 body lengths) in radius. The highest speed of the fish robot was estimated to be approximately 33 mm s-1 (or 0.25 body lengths s-1) and was achieved with a flapping frequency of 0.6-0.8 Hz which also corresponded with the most hydrodynamically efficient mode for tail fin operation. This speed is approximately ten times faster than those for any previously reported artificial muscle based device that also offers real-time speed and directional control. This study contributes to previously published studies on bio-inspired functional devices, demonstrating that electroactive polymer actuators can be real alternatives to conventional means of actuation such as electric motors.

  16. Pittsburgh Fish Fry Locations

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — Lenten Fish Fry records for the Greater Pittsburgh region. Data is collected before and during the Lenten fish fry season each year by Code for Pittsburgh. Data is...

  17. Fish with Chips: Tracking Reef Fish Movements to Evaluate Size and Connectivity of Caribbean Marine Protected Areas

    Science.gov (United States)

    Pittman, Simon J.; Monaco, Mark E.; Friedlander, Alan M.; Legare, Bryan; Nemeth, Richard S.; Kendall, Matthew S.; Poti, Matthew; Clark, Randall D.; Wedding, Lisa M.; Caldow, Chris

    2014-01-01

    Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs) have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves) for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families) moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40–64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness. PMID:24797815

  18. Fish with chips: tracking reef fish movements to evaluate size and connectivity of Caribbean marine protected areas.

    Directory of Open Access Journals (Sweden)

    Simon J Pittman

    Full Text Available Coral reefs and associated fish populations have experienced rapid decline in the Caribbean region and marine protected areas (MPAs have been widely implemented to address this decline. The performance of no-take MPAs (i.e., marine reserves for protecting and rebuilding fish populations is influenced by the movement of animals within and across their boundaries. Very little is known about Caribbean reef fish movements creating a critical knowledge gap that can impede effective MPA design, performance and evaluation. Using miniature implanted acoustic transmitters and a fixed acoustic receiver array, we address three key questions: How far can reef fish move? Does connectivity exist between adjacent MPAs? Does existing MPA size match the spatial scale of reef fish movements? We show that many reef fishes are capable of traveling far greater distances and in shorter duration than was previously known. Across the Puerto Rican Shelf, more than half of our 163 tagged fish (18 species of 10 families moved distances greater than 1 km with three fish moving more than 10 km in a single day and a quarter spending time outside of MPAs. We provide direct evidence of ecological connectivity across a network of MPAs, including estimated movements of more than 40 km connecting a nearshore MPA with a shelf-edge spawning aggregation. Most tagged fish showed high fidelity to MPAs, but also spent time outside MPAs, potentially contributing to spillover. Three-quarters of our fish were capable of traveling distances that would take them beyond the protection offered by at least 40-64% of the existing eastern Caribbean MPAs. We recommend that key species movement patterns be used to inform and evaluate MPA functionality and design, particularly size and shape. A re-scaling of our perception of Caribbean reef fish mobility and habitat use is imperative, with important implications for ecology and management effectiveness.

  19. Ecological characterization of two species of exotic fish, pumpkinseed sunfish (Lepomis gibbosus and largemouth bass (Micropterus salmoides in the international Minho river

    Directory of Open Access Journals (Sweden)

    Ana Cristina Lages

    2015-11-01

    Full Text Available The introduction of exotic species is considered the main cause for the decline of native species. The largemouth bass (Micropterus salmoides and pumpkinseed sunfish (Lepomis gibbosus are two native species from North America, introduced in Portugal to enhance sport fishing. However, their diet and great adaptability made them considered predatory and harmful. In order to understand the ecological impact of M. salmoides and L. gibbosus in the international section of the Minho River, three sampling sites were selected: two in Vila Nova de Cerveira and one in Lapela, at distance of the mouth of the river of 17 and 45 Km, respectively. The fish were gathered using fyke nets and trammel nets, electric fishing and fishing rod, with performed samplings since July 2014 until October 2015. For all fish caught the biometric data (weight, total and fork length, gonad and liver weight, sex, stomach contents analysis were registered as well as collection of otoliths and scales for age reading. Both species feed on small macroinvertebrates specially the juveniles while adults of largemouth bass and pumpkinseed sunfish prefer eat fish and gastropods, respectively. Because L. gibbosus is a recent introduction in the Minho river estuary its abundance increased a lot in the last two years and it was possible verify the increase of the fish population average length. With this work it is intended to evaluate the impact in the Minho River estuary of both exotic species studying the population structure, trophic webs and reproduction.

  20. Fish pass assessment by remote control: a novel framework for quantifying the hydraulics at fish pass entrances

    Science.gov (United States)

    Kriechbaumer, Thomas; Blackburn, Kim; Gill, Andrew; Breckon, Toby; Everard, Nick; Wright, Ros; Rivas Casado, Monica

    2014-05-01

    Fragmentation of aquatic habitats can lead to the extinction of migratory fish species with severe negative consequences at the ecosystem level and thus opposes the target of good ecological status of rivers defined in the EU Water Framework Directive (WFD). In the UK, the implementation of the EU WFD requires investments in fish pass facilities of estimated 532 million GBP (i.e. 639 million Euros) until 2027 to ensure fish passage at around 3,000 barriers considered critical. Hundreds of passes have been installed in the past. However, monitoring studies of fish passes around the world indicate that on average less than half of the fish attempting to pass such facilities are actually successful. There is a need for frameworks that allow the rapid identification of facilities that are biologically effective and those that require enhancement. Although there are many environmental characteristics that can affect fish passage success, past research suggests that variations in hydrodynamic conditions, reflected in water velocities, velocity gradients and turbulences, are the major cues that fish use to seek migration pathways in rivers. This paper presents the first steps taken in the development of a framework for the rapid field-based quantification of the hydraulic conditions downstream of fish passes and the assessment of the attractivity of fish passes for salmonids and coarse fish in UK rivers. For this purpose, a small-sized remote control platform carrying an acoustic Doppler current profiler (ADCP), a GPS unit, a stereo camera and an inertial measurement unit has been developed. The large amount of data on water velocities and depths measured by the ADCP within relatively short time is used to quantify the spatial and temporal distribution of water velocities. By matching these hydraulic features with known preferences of migratory fish, it is attempted to identify likely migration routes and aggregation areas at barriers as well as hydraulic features that

  1. Randomized trial of weight-loss-diets for young adults varying in fish and fish oil content

    NARCIS (Netherlands)

    Thorsdottir, I.; Tomasson, H.; Gunnarsdottir, I.; Gisladottir, E.; Kiely, M.; Parra, M.D.; Bandarra, N.M.; Schaafsma, G.; Martinez, J.A.

    2007-01-01

    Objective: To investigate the effect of including seafood and fish oils, as part of an energy-restricted diet, on weight loss in young overweight adults. Design: Randomized controlled trial of energy-restricted diet varying in fish and fish oil content was followed for 8 weeks. Subjects were

  2. Fishing top predators indirectly affects condition and reproduction in a reef-fish community.

    Science.gov (United States)

    Walsh, S M; Hamilton, S L; Ruttenberg, B I; Donovan, M K; Sandin, S A

    2012-03-01

    To examine the indirect effects of fishing on energy allocation in non-target prey species, condition and reproductive potential were measured for five representative species (two-spot red snapper Lutjanus bohar, arc-eye hawkfish Paracirrhites arcatus, blackbar devil Plectroglyphidodon dickii, bicolour chromis Chromis margaritifer and whitecheek surgeonfish Acanthurus nigricans) from three reef-fish communities with different levels of fishing and predator abundance in the northern Line Islands, central Pacific Ocean. Predator abundance differed by five to seven-fold among islands, and despite no clear differences in prey abundance, differences in prey condition and reproductive potential among islands were found. Body condition (mean body mass adjusted for length) was consistently lower at sites with higher predator abundance for three of the four prey species. Mean liver mass (adjusted for total body mass), an indicator of energy reserves, was also lower at sites with higher predator abundance for three of the prey species and the predator. Trends in reproductive potential were less clear. Mean gonad mass (adjusted for total body mass) was high where predator abundance was high for only one of the three species in which it was measured. Evidence of consistently low prey body condition and energy reserves in a diverse suite of species at reefs with high predator abundance suggests that fishing may indirectly affect non-target prey-fish populations through changes in predation and predation risk. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  3. Trophic interactions between native and introduced fish species in a littoral fish community.

    Science.gov (United States)

    Monroy, M; Maceda-Veiga, A; Caiola, N; De Sostoa, A

    2014-11-01

    The trophic interactions between 15 native and two introduced fish species, silverside Odontesthes bonariensis and rainbow trout Oncorhynchus mykiss, collected in a major fishery area at Lake Titicaca were explored by integrating traditional ecological knowledge and stable-isotope analyses (SIA). SIA suggested the existence of six trophic groups in this fish community based on δ(13)C and δ(15)N signatures. This was supported by ecological evidence illustrating marked spatial segregation between groups, but a similar trophic level for most of the native groups. Based on Bayesian ellipse analyses, niche overlap appeared to occur between small O. bonariensis (<90 mm) and benthopelagic native species (31.6%), and between the native pelagic killifish Orestias ispi and large O. bonariensis (39%) or O. mykiss (19.7%). In addition, Bayesian mixing models suggested that O. ispi and epipelagic species are likely to be the main prey items for the two introduced fish species. This study reveals a trophic link between native and introduced fish species, and demonstrates the utility of combining both SIA and traditional ecological knowledge to understand trophic relationships between fish species with similar feeding habits. © 2014 The Fisheries Society of the British Isles.

  4. Identification of tetrodotoxin and fish species in a dried dressed fish fillet implicated in food poisoning.

    Science.gov (United States)

    Hwang, Deng-Fwu; Hsieh, Yu-Wen; Shiu, Yu-Cheng; Chen, Shu-Kong; Cheng, Chao-An

    2002-02-01

    There were five victims of neurotoxic food poisoning from a dried dressed fish fillet in Changhua County, Taiwan, in February 2000. The toxicity of the dried dressed fish fillets was 243 mouse units per g according to a tetrodotoxin bioassay. The partially purified toxin was identified as tetrodotoxin and anhydrotetrodotoxin. The sequence of the 376-nucleotide region in the cytochrome b gene of the mitochondrial DNA exhibited the same genotype as that of the toxic puffer fish Lagocephalus lunaris. The same single restriction site for Hinfl was found in the polymerase chain reaction (PCR) products from the dried dressed fish fillet and the muscle of L. lunaris, yielding two DNA fragments of 170 and 206 bp. However, no restriction site for Hinfl was found in the PCR products from other toxic puffer fishes, including Takifugu niphobles, Takifugu oblongus, and Takifugu rubripes. Therefore, the species of the dried dressed fish fillet was identified as L. lunaris and its causative agent was identified as tetrodotoxin.

  5. Fish screens at hydroelectric diversions

    International Nuclear Information System (INIS)

    Ott, R.F.

    1994-01-01

    Preventing downstream migrating fish from entering the turbines at hydroelectric projects is a standard mitigation goal of state and federal fishery management agencies. The object is to minimize the adverse impacts to the fish associated with the exclusion and passage through the bypass water conveyance facilities. In the western United States, most of the fishery management agencies have fish screen design criteria that focus on the approach and transportational velocities, maximum opening dimensions of the screen material, and the cleaning standards. Recently, more attention has been given to fish behavioral traits such as attraction and sustained and darting swimming speed, which has resulted in more attention to the position of the screens to the flow and the length of time the downstream migrants are exposed to the screens. Criteria for length of time of exposure, size and position of bypass, flow and velocities in the bypass entrances, discharge requirements back into the receiving water, and exposure to predation have created unique challenges to the fish screen designer. This paper discusses some of the more recent types of fixed fish screens that are being installed at hydroelectric plants that meet these challenges

  6. Sensor Fish: an autonomous sensor package for characterizing complex flow fields and fish passage

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Zhiqun; Martinez, Jayson J.; Lu, Jun

    2016-10-04

    Fish passing through dams or other hydraulic structures may be injured or killed despite advances in turbine design, project operations, and other fish bypass systems. The Sensor Fish (SF) device is an autonomous sensor package that characterizes the physical conditions and stressors to which fish are exposed during passage through hydro facilities. It was designed to move passively as a neutrally buoyant object through severe hydraulic environments, while collecting high-resolution sensor data. Since its first generation1, the SF device has been successfully deployed in many fish passage studies and has evolved to be a major tool for characterizing fish passage conditions during fish passage in the Columbia River Basin. To better accelerate hydropower development, the U.S. Department of Energy Water Power Program provided funding to develop a new generation (Gen 2 SF) to incorporate more capabilities and accommodate a wider range of users over a broader range of turbine designs and operating environments. The Gen 2 SF (Figure 1) is approximately the size and density of a yearling salmon smolt and is nearly neutrally buoyant. It contains three-dimensional (3D) rotation sensors, 3D linear acceleration sensors, a pressure sensor, a temperature sensor, a 3D orientation sensor, a radiofrequency (RF) transmitter, and a recovery module2. A low-power microcontroller collects data from the sensors and stores up to 5 min of data on internal flash memory at a sampling frequency of 2048 Hz. The recovery module makes the SF positively buoyant after a pre-programmed period of time, causing it to float to the surface for recovery.

  7. Classification and coding of commercial fishing injuries by work processes: an experience in the Danish fresh market fishing industry

    DEFF Research Database (Denmark)

    Jensen, Olaf Chresten; Stage, Søren; Noer, Preben

    2005-01-01

    BACKGROUND: Work-related injuries in commercial fishing are of concern internationally. To better identify the causes of injury, this study coded occupational injuries by working processes in commercial fishing for fresh market fish. METHODS: A classification system of the work processes was deve......BACKGROUND: Work-related injuries in commercial fishing are of concern internationally. To better identify the causes of injury, this study coded occupational injuries by working processes in commercial fishing for fresh market fish. METHODS: A classification system of the work processes...... to working with the gear and nets vary greatly in the different fishing methods. Coding of the injuries to the specific working processes allows for targeted prevention efforts....

  8. Anisakidae in fishing products sold in Sicily

    Directory of Open Access Journals (Sweden)

    Vincenzo Ferrantelli

    2014-04-01

    Full Text Available One of the parasite diseases associated with the consumption of raw fish that occurs with some frequency is the anisakiasis, a human disease caused by the accidental ingestion of larval nematodes of the genus Anisakis, family Anisakidae. At the National Reference Centre for Anisakiasis (C.Re.N.A. from October 2012 to February 2013, a number of 231 bony fish (Trichiuridae, Engraulidae, Scombridae and Clupeidae were received from different fishing sites in Sicily. Anisakis pegreffii is the main species detected in fish, as identified by molecular analysis based on polymerase chain reaction-restriction fragment length polymorphism, while Anisakis simplex sensu stricto was found only in Scomber scombrus caught in the Mediterranean Sea (Fishing Areas 37, in the Spanish coast (Fishing Areas 37 and in the Atlantic Ocean (Fishing Areas 34. Larvae of the genus Pseudoterranova were found only in fish caught in the Norwegian Sea.

  9. Marine soundscape shaped by fishing activity.

    Science.gov (United States)

    Coquereau, Laura; Lossent, Julie; Grall, Jacques; Chauvaud, Laurent

    2017-01-01

    Marine communities face anthropogenic pressures that degrade ecosystems. Because underwater soundscapes carry information about habitat quality, we explored whether destructive impacts of fishing could be evaluated via the soundscape. Maerl beds are recognized as biodiversity hotspots and they experience major worldwide degradation owing to fishing. We collected field acoustic recordings in maerl beds exposed to different fishing practices. We found that unfished maerl beds were threefold louder and exhibited sound frequencies more diversified than those recorded in fished maerl beds. Analyses of associated fauna samples indicated that snapping shrimps provided a major contribution to the maerl bed soundscape. Moreover, sea urchins and squat lobsters most likely contributed to differences between the soundscapes of unfished and fished maerl beds. Our results supported the idea that the soundscape can provide valuable information on maerl bed ecosystem health related to fishing activity.

  10. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is

  11. Wild-Caught Versus Farmed Fish – Consumer Perception

    Directory of Open Access Journals (Sweden)

    Tomić Marina

    2017-06-01

    Full Text Available We have limited knowledge of determinants of consumer preferences for wild-caught versus farmed-raised fish, so this work aims to investigate the impact of sociodemographics, habits and frequency of fresh fish consumption, such as involvement in cooking, on the preferences for wild versus farmed fish. A survey was done on a sample of 1151 fish consumers in Croatia. Results showed that female, older consumers, consumers with higher income and those living in coastal parts of Croatia give higher preferences for wild fish and they detect differences between the taste of wild and farmed fish. Consumers with higher levels of habits of fresh fish consumption, who eat fresh fish often and are more involved in cooking, prefer wild-caught fish. These findings provide valuable information for the aquaculture sector, especially for planning marketing strategies for the promotion of farmed fish.

  12. Fish hemoglobins

    Directory of Open Access Journals (Sweden)

    P.C. de Souza

    2007-06-01

    Full Text Available Vertebrate hemoglobin, contained in erythrocytes, is a globular protein with a quaternary structure composed of 4 globin chains (2 alpha and 2 beta and a prosthetic group named heme bound to each one. Having myoglobin as an ancestor, hemoglobin acquired the capacity to respond to chemical stimuli that modulate its function according to tissue requirements for oxygen. Fish are generally submitted to spatial and temporal O2 variations and have developed anatomical, physiological and biochemical strategies to adapt to the changing environmental gas availability. Structurally, most fish hemoglobins are tetrameric; however, those from some species such as lamprey and hagfish dissociate, being monomeric when oxygenated and oligomeric when deoxygenated. Fish blood frequently possesses several hemoglobins; the primary origin of this finding lies in the polymorphism that occurs in the globin loci, an aspect that may occasionally confer advantages to its carriers or even be a harmless evolutionary remnant. On the other hand, the functional properties exhibit different behaviors, ranging from a total absence of responses to allosteric regulation to drastic ones, such as the Root effect.

  13. Evolutionary Dynamics of 5S rDNA and Recurrent Association of Transposable Elements in Electric Fish of the Family Gymnotidae (Gymnotiformes): The Case of Gymnotus mamiraua.

    Science.gov (United States)

    da Silva, Maelin; Barbosa, Patricia; Artoni, Roberto F; Feldberg, Eliana

    2016-01-01

    Gymnotidae is a family of electric fish endemic to the Neotropics consisting of 2 genera: Electrophorus and Gymnotus. The genus Gymnotus is widely distributed and is found in all of the major Brazilian river systems. Physical and molecular mapping data for the ribosomal DNA (rDNA) in this genus are still scarce, with its chromosomal location known in only 11 species. As other species of Gymnotus with 2n = 54 chromosomes from the Paraná-Paraguay basin, G. mamiraua was found to have a large number of 5S rDNA sites. Isolation and cloning of the 5S rDNA sequences from G. mamiraua identified a fragment of a transposable element similar to the Tc1/mariner transposon associated with a non-transcribed spacer. Double fluorescence in situ hybridization analysis of this element and the 5S rDNA showed that they were colocalized on several chromosomes, in addition to acting as nonsyntenic markers on others. Our data show the association between these sequences and suggest that the Tc1 retrotransposon may be the agent that drives the spread of these 5S rDNA-like sequences in the G. mamiraua genome. © 2016 S. Karger AG, Basel.

  14. Perspektif Six Sigma dalam Analisis Manajemen Kualitas Kasus Produksi Fish Fillet di PT Dharma Samudra Fishing Industry, Jakarta

    OpenAIRE

    Farmayanti, Narni; ., Dinarwan; S, I I Fithri Yunindari

    2006-01-01

    Fish fillet is a superior commodity for the company of PT Dharma Samudra Fishing Industry (DSFI), and having the highest production and demand. The product of fish fillet giving a big opportunity for defect level of fish fillet and it´s caused from some mistakes that happen in process production. Hence, the optimalization of input process of fish fillet production is related with six sigma methods application which try to eliminate or minimize mistakes and wastes of time and money. It is hope...

  15. Water intake fish diversion apparatus

    International Nuclear Information System (INIS)

    Taft, E.P. III; Cook, T.C.

    1995-01-01

    A fish diversion apparatus uses a plane screen to divert fish for variety of types of water intakes in order to protect fish from injury and death. The apparatus permits selection of a relatively small screen angle, for example ten degrees, to minimize fish injury. The apparatus permits selection of a high water velocity, for example ten feet per second, to maximize power generation efficiency. The apparatus is especially suitable retrofit to existing water intakes. The apparatus is modular to allow use plural modules in parallel to adjust for water flow conditions. The apparatus has a floor, two opposite side walls, and a roof which define a water flow passage and a plane screen within the passage. The screen is oriented to divert fish into a fish bypass which carries fish to a safe discharge location. The dimensions of the floor, walls, and roof are selected to define the dimensions of the passage and to permit selection of the screen angle. The floor is bi-level with a level upstream of the screen and a level beneath screen selected to provide a uniform flow distribution through the screen. The apparatus may include separation walls to provide a water flow channel between the apparatus and the water intake. Lead walls may be used to adjust water flow conditions into the apparatus. The apparatus features stoplog guides near its upstream and downstream ends to permit the water flow passage to be dewatered. 3 figs

  16. Temperature and diet effects on omnivorous fish performance: Implications for the latitudinal diversity gradient in herbivorous fishes

    Science.gov (United States)

    Behrens, M.D.; Lafferty, K.D.

    2007-01-01

    Herbivorous fishes show a clear latitudinal diversity gradient, making up a larger proportion of the fish species in a community in tropical waters than in temperate waters. One proposed mechanism that could drive this gradient is a physiological constraint due to temperature. One prediction based on this mechanism is that if herbivorous fishes could shift their diet to animal material, they would be better able to grow, survive, and reproduce in cold waters. We tested this prediction on the omnivore Girella nigricans under different temperature and diet regimes using RNA-DNA ratios as an indicator of performance. Fish had increased performance (100%) at low temperatures (12??C) when their diet was supplemented with animal material. In contrast, at higher temperatures (17, 22, and 27??C) fish showed no differences between diets. This indicates that omnivorous fishes could increase their performance at low temperatures by consuming more animal matter. This study supports the hypothesis that a relative increase in the nutritional value of plant material at warmer temperatures could drive the latitudinal diversity gradient in herbivorous fishes. ?? 2007 NRC.

  17. Values, attitudes and intention to consume wild fish versus farmed fish in Nha Trang

    OpenAIRE

    Nelka Rajani, Pemattuge

    2010-01-01

    The primary purpose of this study was to investigate the consumers’ values and the difference in consumption, attitude and intention to consume wild fish versus farmed fish in Vietnam. Second, it aimed to investigate the relationship between values, attitudes and intention to consume wild versus farmed fish by applying value-attitude-behavior model. The measurement scales used here were adapted from previous studies found in the literature. The survey was conducted in Nha Trang, Vietnam, amon...

  18. The evaluation of energy in fish feed

    NARCIS (Netherlands)

    Haidar, Mahmoud

    2017-01-01

    New and alternative plant ingredients are increasingly incorporated in fish feed due to the scarcity of captured fish and increased fishmeal and fish oil prices. As a result, current fish feeds are characterized by a highly variable ingredients composition, leading to a similar variability in the

  19. Undulatory fish swimming : from muscles to flow

    NARCIS (Netherlands)

    Müller, U.K.; Leeuwen, van J.L.

    2006-01-01

    Undulatory swimming is employed by many fish for routine swimming and extended sprints. In this biomechanical review, we address two questions: (i) how the fish's axial muscles power swimming; and (ii) how the fish's body and fins generate thrust. Fish have adapted the morphology of their axial

  20. The effect of monsoon variability on fish landing in the Sadeng Fishing Port of Yogyakarta, Indonesia

    Science.gov (United States)

    Subarna, D.

    2018-03-01

    The volume of landing fish of the Sadeng Fishing Port within certain months showed an increase from year to year, especially during June, July and August (JJA). While in other months the fish production was low. The purpose of this research was to understand the influence of monsoon variability on fish landing in the Sadeng Fishing Port. Data were analyzed descriptively as spatial and temporal catch. Data were namely catch fish production collected from fishing port, while satellite and HYCOM model during 2011–2012 period were selected. The wind data, sea surface temperature (SST) and chlorophyll-a were analyzed from ASCAT and MODIS sensors during the Southeast Monsoon. The result showed the wind from the southeasterly provide wind stress at sea level and caused Ekman Transport to move away water mass from the sea shore. The lost water mass in the ocean surface was replaced by cold water from deeper layer which was rich in nutrients. The distribution of chlorophyll-a during the Southeast Monsoon was relatively higher in the southern coast of Java than during the Northwest monsoon. The SST showed approximately 25.3 °C. The abundance of nutrients indicated by the distribution of chlorophyll-a around the coast during the Southeast Monsoon, will enhance the arrival of larger fish. Thus, it can be understood that during June, July, and August the catch production is higher than the other months.

  1. [Progress in transgenic fish techniques and application].

    Science.gov (United States)

    Ye, Xing; Tian, Yuan-Yuan; Gao, Feng-Ying

    2011-05-01

    Transgenic technique provides a new way for fish breeding. Stable lines of growth hormone gene transfer carps, salmon and tilapia, as well as fluorescence protein gene transfer zebra fish and white cloud mountain minnow have been produced. The fast growth characteristic of GH gene transgenic fish will be of great importance to promote aquaculture production and economic efficiency. This paper summarized the progress in transgenic fish research and ecological assessments. Microinjection is still the most common used method, but often resulted in multi-site and multi-copies integration. Co-injection of transposon or meganuclease will greatly improve the efficiency of gene transfer and integration. "All fish" gene or "auto gene" should be considered to produce transgenic fish in order to eliminate misgiving on food safety and to benefit expression of the transferred gene. Environmental risk is the biggest obstacle for transgenic fish to be commercially applied. Data indicates that transgenic fish have inferior fitness compared with the traditional domestic fish. However, be-cause of the genotype-by-environment effects, it is difficult to extrapolate simple phenotypes to the complex ecological interactions that occur in nature based on the ecological consequences of the transgenic fish determined in the laboratory. It is critical to establish highly naturalized environments for acquiring reliable data that can be used to evaluate the environ-mental risk. Efficacious physical and biological containment strategies remain to be crucial approaches to ensure the safe application of transgenic fish technology.

  2. Fish is healthy, but too expensive

    DEFF Research Database (Denmark)

    Jeppesen, Lisbeth Fruensgaard; Stacey, Julia

    2006-01-01

    Nowadays most consumers perceive fish as a healthy and nutritious meal and many are fully aware of the various nutritious values of fish. In spite of this, the consumption of fish has diminished or stagnated in many European countries in recent years....

  3. Forecasting Tools Point to Fishing Hotspots

    Science.gov (United States)

    2009-01-01

    Private weather forecaster WorldWinds Inc. of Slidell, Louisiana has employed satellite-gathered oceanic data from Marshall Space Flight Center to create a service that is every fishing enthusiast s dream. The company's FishBytes system uses information about sea surface temperature and chlorophyll levels to forecast favorable conditions for certain fish populations. Transmitting the data to satellite radio subscribers, FishBytes provides maps that guide anglers to the areas they are most likely to make their favorite catch.

  4. Nutrition, feeding, and behavior of fish.

    Science.gov (United States)

    Lall, Santosh P; Tibbetts, Sean M

    2009-05-01

    Nutrition and feeding influence growth, reproduction, and health of fish and their response to physiologic and environmental stressors and pathogens. The basics of fish metabolism are similar to those of warm-blooded animals in that they involve food intake, digestion, absorption, and transport of nutrients to the various tissues. Fish, however, being the most primitive form of vertebrates, possess some distinguishing features which will be discussed. Unlike warm-blooded animals, which are homoeothermic, fish are poikilothermic, so their body temperature and metabolic rate depends on the water temperature and this has practical implications for the nutrition, feeding and health of fish. Several behavioral responses have been linked to methods of feeding, feeding habits, frequency of feeding, mechanisms of food detection, and food preferences. Fish are also unique among vertebrates in their ability to absorb minerals not only from their diets but also from water through their gills and skin.

  5. Fish consumption limit for mercury compounds

    Directory of Open Access Journals (Sweden)

    Abbas Esmaili-Sari

    2011-09-01

    Full Text Available Background and objectives: Methyl mercury can carry out harmful effects on the reproductive, respiratory, and nervous system of human. Moreover, mercury is known as the most toxic heavy metal in nature. Fish and seafood consumption is the major MeHg exposure route for human. The present study tries to cover researches which have been conducted on mercury levels in 21 species of fish from Persian Gulf, Caspian Sea and Anzali Wetland during the past 6 years, and in addition to stating mercury level, it provides recommendations about the restriction of monthly fish consumption for each species separately. Material and methods: Fish samples were transferred to the laboratory and stored in refrigerator under -20oC until they were dissected. Afterwards, the muscle tissues were separated and dried. The dried samples were ground and changed into a homogenous powder and then the mercury concentration rate has been determined by advanced mercury analyzer, model 254. Results: In general, mercury contamination in fishes caught from Anzali Wetland was much more than fishes from Caspian Sea. Also, from among all studied fishes, oriental sole (Euryglossa orientalis, caught from Persian Gulf, allocated the most mercury level to itself with the rate of 5.61ml per kg., therefore, it exercises a severe consumption restriction for pregnant women and vulnerable groups. Conclusion: Based on the calculations, about 50% of fishes, mostly with short food chain, can be easily consumed during the year. However, with regard to Oriental sole (Euryglossa orientalis and shark (Carcharhinus dussumieri, caught from Persian Gulf, special consideration should be taken in their consumption. On the other hand, careful planning should be made for the high rate of fish consumption among fishing community.

  6. The offshore benthic fish community

    Science.gov (United States)

    Lantry, Brian F.; Lantry, Jana R.; Weidel, Brian C.; Walsh, Maureen; Hoyle, James A.; Schaner, Teodore; Neave, Fraser B.; Keir, Michael

    2014-01-01

    Lake Ontario’s offshore benthic fish community includes primarily slimy sculpin, lake whitefish, rainbow smelt, lake trout, burbot, and sea lamprey. Of these, lake trout have been the focus of an international restoration effort for more than three decades (Elrod et al. 1995; Lantry and Lantry 2008). The deepwater sculpin and three species of deepwater ciscoes (Coregonus spp.) that were historically important in the offshore benthic zone became rare or were extirpated by the 1960s (Christie 1973; Owens et al. 2003; Lantry et al. 2007b; Roth et al. 2013). Ecosystem changes continue to influence the offshore benthic fish community, including the effects of dreissenid mussels, the near disappearance of burrowing amphipods (Diporeia spp.) (Dermott et al. 2005; Watkins et al. 2007), and the increased abundance and expanded geographic distribution of round goby (see Nearshore Fish Community chapter) (Lantry et al. 2007b). The fish-community objectives for the offshore benthic fish community, as described by Stewart et al. (1999), are:

  7. North Slope, Alaska ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species for the North Slope of Alaska. Vector...

  8. Health effects of fish and fish oils

    National Research Council Canada - National Science Library

    Chandra, Ranjit Kumar

    1989-01-01

    .... Based on epidemiologic data, it has been suggested that a fish-containing diet is beneficial in the prevention and management of a variety of disorders including coronary heart disease, hypertension, and psoriasis...

  9. Arthropod pests of dried fish and fish by product in a tropical urban ...

    African Journals Online (AJOL)

    A four months research survey of arthropod pests infesting dried fish sold in a tropical urban community market (Ogige), Nsukka, Ngeria showed that 10 genera o dried freshwater fish (Synodontis, Hemisynodontis, Oreochromis, Hepsetus, Gymnarchus, Labeo, Protopterus, Heterobranchus, Alestes, Heterotis) and two ...

  10. Parvalbumin in fish skin-derived gelatin: is there a risk for fish allergic consumers?

    Science.gov (United States)

    Koppelman, S J; Nordlee, J A; Lee, P-W; Happe, R P; Hessing, M; Norland, R; Manning, T; Deschene, R; De Jong, G A H; Taylor, S L

    2012-01-01

    The major allergen parvalbumin was purified from cod muscle tissues, and polyclonal antibodies were raised towards it. The antibodies were tested for specificity and an enzyme-linked immunosorbent assay (ELISA) was developed using these antibodies. The ELISA was applied to measure parvalbumin in cod skin, the starting material for fish gelatin made from deep sea, wild fish. The ELISA was sufficiently sensitive (LLOQ = 0.8 ng ml(-1) in extracts, corresponding to 0.02 µg of parvalbumin per g of tissue), and did not cross-react with common food constituents. Fish gelatin, wine and beer, matrices for the potential use of this ELISA, did not cause disturbance of the assay performance. The data show that the parvalbumin content in cod muscle tissue is 6.25 mg g(-1), while the skins contained considerably less, 0.4 mg g(-1). Washing of the skins, a common industrial procedure during the manufacturing of fish gelatin, reduced the level of parvalbumin about 1000-fold to 0.5 µg g(-1), or 0.5 ppm. From 95 commercial lots of fish gelatin it is shown that 73 are below 0.02 µg g(-1) parvalbumin. From the other 22 lots, the one with the highest concentration contained 0.15 µg g(-1) of parvalbumin. These levels are generally assumed to be safe for fish-allergic individuals.

  11. Fishing. Unit 1, Colorado Division of Wildlife.

    Science.gov (United States)

    Hetzel, George K.; Smith, Dwight R.

    This booklet on fishing is part of a series developed to encourage youth to pursue outdoor projects. Fish anatomy, equipment, casting techniques, knot and leader tying, hooks, fishing areas, cleaning and cooking fish, types of bait, lures, and regulations are discussed and illustrated. Suggested activities and field trips are listed. (MR)

  12. Farm-level risk factors for fish-borne zoonotic trematode infection in integrated small-scale fish farms in northern Vietnam.

    Directory of Open Access Journals (Sweden)

    Van Thi Phan

    Full Text Available BACKGROUND: Northern Vietnam is an endemic region for fish-borne zoonotic trematodes (FZT, including liver and intestinal flukes. Humans acquire the FZT infection by eating raw or inadequately cooked fish. The production of FZT-free fish in aquaculture is a key component in establishing a sustainable program to prevent and control the FZT transmission to humans. Interventions in aquaculture should be based on knowledge of the main risk factors associated with FZT transmission. METHODOLOGY/PRINCIPAL FINDINGS: A longitudinal study was carried out from June 2006 to May 2007 in Nam Dinh province, Red River Delta to investigate the development and risk factors of FZT infections in freshwater cultured fish. A total of 3820 fish were sampled six times at two-month intervals from 96 fish farms. Logistic analysis with repeated measurements was used to evaluate potential risk factors based on information collected through questionnaire interviews with 61 fish farm owners. The results showed that the FZT infections significantly increased from first sampling in June to July 2006 (65% to sixth sampling in April to May, 2007 (76%. The liver fluke, Clonorchis sinensis and different zoonotic intestinal flukes including Haplochis pumilio, H. taichui, H. yokogawai, Centrocestus formosanus and Procerovum varium were found in sampled fish. Duration of fish cultured (sampling times, mebendazole drug self-medication of household members, presence of snails in the pond, and feeding fish with green vegetation collected outside fish farms all had a significant effect on the development of FZT prevalence in the fish. CONCLUSIONS/SIGNIFICANCE: The FZT prevalence in fish increased by 11 percentage points during a one-year culture period and the risk factors for the development of infection were identified. Results also highlight that the young fish are already highly infected when stocked into the grow-out systems. This knowledge should be incorporated into control

  13. Ecomorphology as a predictor of fish diet: a case study on the North Sea benthic fish community

    NARCIS (Netherlands)

    Diderich, W.P.

    2006-01-01

    A methodological approach based on fish ecomorphology was chosen to predict potential fish diet. This study tests a method used in earlier research on a marine ecosystem containing phylogenetically diverse organisms: the North Sea. Fish feeding morphology imposes constraints on feeding options. A

  14. African Fish Biodiversity, Fishbase and Fishculture

    Directory of Open Access Journals (Sweden)

    Boden, G.

    2004-01-01

    Full Text Available At present, about 28 600 fish species are considered valid, whilst the total number is estimated at 30 000 to 35 000. For Africa, about 3 000 valid fresh- and brackish water species are currently recognized. Conserving the biodiversity of these fishes and at the same time managing their exploitation in a sustainable way is a difficult exercise. In sub-Saharan Africa, the importance of aquaculture is not very high. Nonetheless, 18 different species are used commercially, of which six have a non-African origin. Documenting and characterizing the ichthyodiversity is vital for conservation and sustainable development purposes. The presence of a large collection, a specialised library and a considerable know-how in the Africa Museum has led to various revisions, checklists, species (redescriptions and regional guides. All the information on African fishes is currently being entered in FishBase, a huge freely accessible database with information on the taxonomy, ecology and various other aspects of the biology of fishes, based on scientific publications and reviewed by specialists. FishBase also includes high quality tools for applied research on fishes, such as a disease wizard, biogeography tools, trophic pyramids, and the species invasiveness tool.

  15. Effects of fish density and river fertilization on algal standing stocks, invertebrates communities, and fish production in an Arctic River

    Science.gov (United States)

    Deegan, Linda A.; Peterson, B.J.; Golden, H.; McIvor, C.C.; Miller, M.C.

    1997-01-01

    This study examined the relative importance of bottom-up and top-down controls of an arctic stream food web by simultaneous manipulation of the top predator and nutrient availability. We created a two-step trophic system (algae to insects) by removal of the top predator (Arctic grayling, Thymallus arcticus) in fertilized and control stream reaches. Fish abundance was also increased 10 times to examine the effect of high fish density on stream ecosystem dynamics and fish. We measured the response of epilithic algae, benthic and drifting insects, and fish to nutrient enrichment and to changes in fish density. Insect grazers had little effect on algae and fish had little effect on insects. In both the control and fertilized reaches, fish growth, energy storage, and reproductive response of females declined with increased fish density. Fish growth and energy storage were more closely correlated with per capita insect availability than with per capita algal standing stock

  16. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: South Florida: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine and estuarine fish species in South Florida. Vector polygons in this data set represent fish...

  17. Fish and robots swimming together in a water tunnel: robot color and tail-beat frequency influence fish behavior.

    Directory of Open Access Journals (Sweden)

    Giovanni Polverino

    Full Text Available The possibility of integrating bioinspired robots in groups of live social animals may constitute a valuable tool to study the basis of social behavior and uncover the fundamental determinants of animal functions and dysfunctions. In this study, we investigate the interactions between individual golden shiners (Notemigonus crysoleucas and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish positional preference with respect to the robot is experimentally analyzed as the robot's color pattern and tail-beat frequency are varied. Behavioral observations are corroborated by particle image velocimetry studies aimed at investigating the flow structure behind the robotic fish. Experimental results show that the time spent by golden shiners in the vicinity of the bioinspired robotic fish is the highest when the robot mimics their natural color pattern and beats its tail at the same frequency. In these conditions, fish tend to swim at the same depth of the robotic fish, where the wake from the robotic fish is stronger and hydrodynamic return is most likely to be effective.

  18. Fish and robots swimming together in a water tunnel: robot color and tail-beat frequency influence fish behavior.

    Science.gov (United States)

    Polverino, Giovanni; Phamduy, Paul; Porfiri, Maurizio

    2013-01-01

    The possibility of integrating bioinspired robots in groups of live social animals may constitute a valuable tool to study the basis of social behavior and uncover the fundamental determinants of animal functions and dysfunctions. In this study, we investigate the interactions between individual golden shiners (Notemigonus crysoleucas) and robotic fish swimming together in a water tunnel at constant flow velocity. The robotic fish is designed to mimic its live counterpart in the aspect ratio, body shape, dimension, and locomotory pattern. Fish positional preference with respect to the robot is experimentally analyzed as the robot's color pattern and tail-beat frequency are varied. Behavioral observations are corroborated by particle image velocimetry studies aimed at investigating the flow structure behind the robotic fish. Experimental results show that the time spent by golden shiners in the vicinity of the bioinspired robotic fish is the highest when the robot mimics their natural color pattern and beats its tail at the same frequency. In these conditions, fish tend to swim at the same depth of the robotic fish, where the wake from the robotic fish is stronger and hydrodynamic return is most likely to be effective.

  19. Investigation of Fish Consumption in Giresun City

    OpenAIRE

    Mustafa Türkmen; Aysun Türkmen; Köksal Duran

    2016-01-01

    This study aimed to investigate the fish consumption in Giresun by survey method. Fish meat was compared with other meat types according to education, level of income, consumption rate and quantity. In research carried out according to the random sampling method. Questions were asked face to face a total of 433 persons. A total 428 participants (98.9%) stated that they consumed fish. However, the most consumed meat type is chicken, second is fish. A total 91% participant preferred marine fish...

  20. Combined heat and power economic dispatch by a fish school search algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Leonardo Trigueiro dos; Costa e Silva, Marsil de Athayde [Undergraduate in Mechatronics Engineering, Pontifical Catholic University of Parana, Curitiba, PR (Brazil); Coelho, Leandro dos Santos [Industrial and Systems Engineering Graduate Program, PPGEPS, Pontifical Catholic University of Parana, Curitiba, PR (Brazil)], e-mail: leandro.coelho@pucpr.br

    2010-07-01

    The conversion of primary fossil fuels, such as coal and gas, to electricity is a a relatively inefficient process. Even the most modern combined cycle plants can only achieve efficiencies of between 50-60%. A great portion of the energy wasted in this conversion process is released to the environment as waste heat. The principle of combined heat and power, also known as cogeneration, is to recover and make beneficial use of this heat, significantly raising the overall efficiency of the conversion process. However, the optimal utilization of multiple combined heat and power systems is a complicated problem which needs powerful methods to solve. This paper presents a fish school search (FSS) algorithm to solve the combined heat and power economic dispatch problem. FSS is a novel approach recently proposed to perform search in complex optimization problems. Some simulations presented in the literature indicated that FSS can outperform many bio-inspired algorithms, mainly in multimodal functions. The search process in FSS is carried out by a population of limited-memory individuals - the fishes. Each fish represents a possible solution to the problem. Similarly to particle swarm optimization or genetic algorithm, search guidance in FSS is driven by the success of some individual members of the population. A four-unit system proposed recently which is a benchmark case in the power systems field has been validated as a case study in this paper. (author)

  1. Swimming Performance of Toy Robotic Fish

    Science.gov (United States)

    Petelina, Nina; Mendelson, Leah; Techet, Alexandra

    2015-11-01

    HEXBUG AquaBotsTM are a commercially available small robot fish that come in a variety of ``species''. These models have varying caudal fin shapes and randomly-varied modes of swimming including forward locomotion, diving, and turning. In this study, we assess the repeatability and performance of the HEXBUG swimming behaviors and discuss the use of these toys to develop experimental techniques and analysis methods to study live fish swimming. In order to determine whether these simple, affordable model fish can be a valid representation for live fish movement, two models, an angelfish and a shark, were studied using 2D Particle Image Velocimetry (PIV) and 3D Synthetic Aperture PIV. In a series of experiments, the robotic fish were either allowed to swim freely or towed in one direction at a constant speed. The resultant measurements of the caudal fin wake are compared to data from previous studies of a real fish and simplified flapping propulsors.

  2. Some conclusions of studies on irradiation of whole fish aboard fishing vessels

    International Nuclear Information System (INIS)

    Reinacher, E.; Ehlermann, D.A.E.

    1978-01-01

    Studies were conducted on irradiation of whole redfish and haddock (at 100 krad) and subsequent storage of the irradiated fish for up to approx. 30 days in ice. The fish were organoleptically evaluated at intervals during storage. The results show no significant difference in organoleptic quality between irradiated and non-irradiated samples during storage for [de

  3. 25 CFR 242.5 - Disposition of unmarketable fish.

    Science.gov (United States)

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Disposition of unmarketable fish. 242.5 Section 242.5 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR FISH AND WILDLIFE COMMERCIAL FISHING ON RED LAKE INDIAN RESERVATION § 242.5 Disposition of unmarketable fish. All unmarketable live fish taken...

  4. The technology of fish-vegetable feed production

    Directory of Open Access Journals (Sweden)

    Mukatova M. D.

    2016-09-01

    Full Text Available Perspective direction of the Volga-Caspian basin fisheries is increasing the productivity of aquaculture production which requires the availability of sufficient quantities of feed. The cutting waste of carp and crucian carp, crayfish processing (cephalothorax, wheat bran, soy isolate, freshwater plants – pondweed perfoliate, fish-vegetable ration, produced feeding staffs have been investigated. In researching samples of manufactured pelleted feeds the standard methods adopted in the animal feed industry have been used. The number of nitrogen-free extractives and energy value has been determined by calculation. The composition of fish-vegetable ration has been worked out. Some manufacturing inspection of fish-vegetable feed technology using proofing process has been carried out. The possibility of manufacturing on the basis of crushed fish waste of the company LLC "VES" and dry ingredients of fish-vegetable feed has been determined; the output of feed at water content of not more than 10 % is 43 % of feed mix based on the mass of directed waste equal to 84 %. The pilot batch of dry fish-vegetable feed has been investigated to establish quality indicators. It has been determined that fish-vegetable feed meets the requirements of GOST 10385–2014 "Combined feeding staffs for fishes. General specifications" as for main quality indicators and refers to economic grower for catfish and carp fish weighing more than 50 g. This reveals good palatability of the experimental batch of floating feed by carp fish species and African catfish. Thus, fish-vegetable feed manufacturing technology can be implemented in the production for processing secondary raw materials: waste from butchering fish by grinding, cooking, mixing with selected vegetable fillings which is waste of flour or grain processing industries and freshwater plants mowed annually during the reclamation works on the Volga delta.

  5. 21 CFR 172.340 - Fish protein isolate.

    Science.gov (United States)

    2010-04-01

    ... Special Dietary and Nutritional Additives § 172.340 Fish protein isolate. (a) The food additive fish... accordance with recognized good manufacturing practice for fish to be used as human food. (4) The additive... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Fish protein isolate. 172.340 Section 172.340 Food...

  6. Targeting Abundant Fish Stocks while Avoiding Overfished Species: Video and Fishing Surveys to Inform Management after Long-Term Fishery Closures

    Science.gov (United States)

    2016-01-01

    Historically, it has been difficult to balance conservation goals and yield objectives when managing multispecies fisheries that include stocks with various vulnerabilities to fishing. As managers try to maximize yield in mixed-stock fisheries, exploitation rates can lead to less productive stocks becoming overfished. In the late 1990s, population declines of several U.S. West Coast groundfish species caused the U.S. Pacific Fishery Management Council to create coast-wide fishery closures, known as Rockfish Conservation Areas, to rebuild overfished species. The fishery closures and other management measures successfully reduced fishing mortality of these species, but constrained fishing opportunities on abundant stocks. Restrictive regulations also caused the unintended consequence of reducing fishery-dependent data available to assess population status of fished species. As stocks rebuild, managers are faced with the challenge of increasing fishing opportunities while minimizing fishing mortality on rebuilding species. We designed a camera system to evaluate fishes in coastal habitats and used experimental gear and fishing techniques paired with video surveys to determine if abundant species could be caught in rocky habitats with minimal catches of co-occurring rebuilding species. We fished a total of 58 days and completed 741 sets with vertical hook-and-line fishing gear. We also conducted 299 video surveys in the same locations where fishing occurred. Comparison of fishing and stereo-video surveys indicated that fishermen could fish with modified hook-and-line gear to catch abundant species while limiting bycatch of rebuilding species. As populations of overfished species continue to recover along the U.S. West Coast, it is important to improve data collection, and video and fishing surveys may be key to assessing species that occur in rocky habitats. PMID:28002499

  7. Ford Hatchery; Washington Department of Fish and Wildlife Fish Program, Hatcheries Division, Annual Report 2003.

    Energy Technology Data Exchange (ETDEWEB)

    Lovrak, Jon; Ward, Glen

    2004-01-01

    Bonneville Power Administration's participation with the Washington Department of Fish and Wildlife, Ford Hatchery, provides the opportunity for enhancing the recreational and subsistence kokanee fisheries in Banks Lake. The artificial production and fisheries evaluation is done cooperatively through the Spokane Hatchery, Sherman Creek Hatchery (WDFW), Banks Lake Volunteer Net Pen Project, and the Lake Roosevelt Fisheries Evaluation Program. Ford Hatchery's production, together with the Sherman Creek and the Spokane Tribal Hatchery, will contribute to an annual goal of one million kokanee yearlings for Lake Roosevelt and 1.4 million kokanee fingerlings and fry for Banks Lake. The purpose of this multi-agency program is to restore and enhance kokanee salmon and rainbow trout populations in Lake Roosevelt and Banks Lake due to Grand Coulee Dam impoundments. The Ford Hatchery will produce 9,533 lbs. (572,000) kokanee annually for release as fingerlings into Banks Lake in October. An additional 2,133 lbs. (128,000) kokanee will be transferred to net pens on Banks Lake at Electric City in October. The net pen raised kokanee will be reared through the fall, winter, and early spring to a total of 8,533 lbs and released in May. While the origin of kokanee comes from Lake Whatcom, current objectives will be to increase the use of native (or, indigenous) stocks for propagation in Banks Lake and the Upper Columbia River. Additional stocks planned for future use in Banks Lake include Lake Roosevelt kokanee and Meadow Creek kokanee. The Ford Hatchery continues to produce resident trout (80,584 lb. per year) to promote the sport fisheries in trout fishing lakes in eastern Washington (WDFW Management, Region 1). Operation and maintenance funding for the increased kokanee program was implemented in FY 2001 and scheduled to continue through FY 2010. Funds from BPA allow for an additional employee at the Ford Hatchery to assist in the operations and maintenance associated

  8. Fishing long-fingered bats (Myotis capaccinii) prey regularly upon exotic fish

    DEFF Research Database (Denmark)

    Aizpurua, Ostaizka; Garin, Inazio; Alberdi, Antton

    2013-01-01

    The long-fingered bat Myotis capaccinii is a European trawling bat reported to feed on fish in several Mediterranean locations, but the ecological circumstances of this behavior have not yet been studied. To elucidate the importance of fishing in this bat's diet, we evaluated the frequency...

  9. The Impact of Marine Protected Areas on Reef-Wide Population Structure and Fishing-Induced Phenotypes in Coral-Reef Fishes

    Science.gov (United States)

    Fidler, Robert Young, III

    Overfishing and destructive fishing practices threaten the sustainability of fisheries worldwide. In addition to reducing population sizes, anthropogenic fishing effort is highly size-selective, preferentially removing the largest individuals from harvested stocks. Intensive, size-selective mortality induces widespread phenotypic shifts toward the predominance of smaller and earlier-maturing individuals. Fish that reach sexual maturity at smaller size and younger age produce fewer, smaller, and less viable larvae, severely reducing the reproductive capacity of exploited populations. These directional phenotypic alterations, collectively known as "fisheries-induced evolution" (FIE) are among the primary causes of the loss of harvestable fish biomass. Marine protected areas (MPAs) are one of the most widely utilized components of fisheries management programs around the world, and have been proposed as a potential mechanism by which the impacts of FIE may be mitigated. The ability of MPAs to buffer exploited populations against fishing pressure, however, remains debated due to inconsistent results across studies. Additionally, empirical evidence of phenotypic shifts in fishes within MPAs is lacking. This investigation addresses both of these issues by: (1) using a categorical meta-analysis of MPAs to standardize and quantify the magnitude of MPA impacts across studies; and (2) conducting a direct comparison of life-history phenotypes known to be influenced by FIE in six reef-fish species inside and outside of MPAs. The Philippines was used as a model system for analyses due to the country's significance in global marine biodiversity and reliance on MPAs as a fishery management tool. The quantitative impact of Philippine MPAs was assessed using a "reef-wide" meta-analysis. This analysis used pooled visual census data from 39 matched pairs of MPAs and fished reefs surveyed twice over a mean period of 3 years. In 17 of these MPAs, two additional surveys were conducted

  10. Fish habitat mitigation measures for hydrotechnical projects

    International Nuclear Information System (INIS)

    McPhail, G.D.; MacMillan, D.B.; Katopodis, C.

    1992-01-01

    In recent years, the identification and mitigation of environmental impacts of hydrotechnical projects, particularly on fish and fish habitats, have become a major component of project planning and design. Potential impacts to fish and fish habitat may include increased fish mortality, decreased species diversity, and loss or decreases in fish production due to loss of habitat or alteration of its suitability. These impacts arise from flooding of riverine habitat, alteration of flow quantity and distribution, changes in morphology, and alteration of water quality, including suspended sediments, temperature, dissolved oxygen, and mercury. The results of a study for the Canadian Federal Department of Fisheries and Oceans Central and Arctic Region, examining fish habitat mitigation techniques for their applicability to hydrotechnical projects in Canada are summarized. The requirements for achievement and verification of the no net loss policy for a project are discussed. 10 refs., 2 tabs

  11. 77 FR 30995 - Permits; Foreign Fishing

    Science.gov (United States)

    2012-05-24

    ... Office of International Affairs at 1315 East-West Highway, Silver Spring, MD 20910 (phone: (301) 427-8365... fishing consisting solely of transporting fish or fish products at sea from a point within the United States Exclusive Economic Zone (EEZ) or, with the concurrence of a state, within the boundaries of that...

  12. 78 FR 36526 - Permits; Foreign Fishing

    Science.gov (United States)

    2013-06-18

    ... of International Affairs at 1315 East-West Highway, Silver Spring, MD 20910 (phone: (301) 427-8386... engage in fishing consisting solely of transporting fish or fish products at sea from a point within the United States Exclusive Economic Zone (EEZ) or, with the concurrence of a state, within the boundaries of...

  13. Proxy measures of fitness suggest coastal fish farms can act as population sources and not ecological traps for wild gadoid fish.

    Directory of Open Access Journals (Sweden)

    Tim Dempster

    Full Text Available BACKGROUND: Ecological traps form when artificial structures are added to natural habitats and induce mismatches between habitat preferences and fitness consequences. Their existence in terrestrial systems has been documented, yet little evidence suggests they occur in marine environments. Coastal fish farms are widespread artificial structures in coastal ecosystems and are highly attractive to wild fish. METHODOLOGY/PRINCIPAL FINDINGS: To investigate if coastal salmon farms act as ecological traps for wild Atlantic cod (Gadus morhua and saithe (Pollachius virens, we compared proxy measures of fitness between farm-associated fish and control fish caught distant from farms in nine locations throughout coastal Norway, the largest coastal fish farming industry in the world. Farms modified wild fish diets in both quality and quantity, thereby providing farm-associated wild fish with a strong trophic subsidy. This translated to greater somatic (saithe: 1.06-1.12 times; cod: 1.06-1.11 times and liver condition indices (saithe: 1.4-1.8 times; cod: 2.0-2.8 times than control fish caught distant from farms. Parasite loads of farm-associated wild fish were modified from control fish, with increased external and decreased internal parasites, however the strong effect of the trophic subsidy overrode any effects of altered loads upon condition. CONCLUSIONS AND SIGNIFICANCE: Proxy measures of fitness provided no evidence that salmon farms function as ecological traps for wild fish. We suggest fish farms may act as population sources for wild fish, provided they are protected from fishing while resident at farms to allow their increased condition to manifest as greater reproductive output.

  14. Freshwater fish Fauna and Restock Fish Activities of Reservoir in the Dardanelles (Canakkale-Turkey

    Directory of Open Access Journals (Sweden)

    Hüseyin SASI

    2012-06-01

    Full Text Available Turkey has, with geographic location including Istanbul and Çanakkale straits the system, 178,000 km in length streams, 906,000 ha of natural lakes, and 411,800 ha of dam lakes, and 28,000 ha of ponds due to richness inland waters which include freshwater fish. The fingerling fish (fry were restocked approximately 250,000,000 in natural lakes, dam lakes and ponds for fisheries between years of 1979 and 2005. Canakkale has rich freshwater potential with 7 major rivers (Büyükdere, Karamenderes stream, Kavak brook, Kocacay stream, Sarıcay stream, Tuzla brook, Umurbey brook, 7 Dam Lakes (Atikhisar, Zeytinlikoy, Bayramic, Bakacak, Tayfur, Umurbey and Yenice-Gönen Dam lakes. In the studies, it has been determined that 15 fish species belonging to 6 families (Anguillidae, Atherinidae, Salmonidae, Cobitidae, Cyprinidae and Poecilidae can be found in reservoirs. Fish restocking of the activities of the reservoir until today approximately 1,120,000 (Cyprinus carpio L., 1758 is introduced. In this study, the activity of Canakkale province in the fish restocking and reservoir exploiting possibilities were discussed in view of reservoir fisheries potential which is used insufficiently today.

  15. [Study on tetrodotoxin detection and toxic puffer fish identification of roasted fish fillet at the retail in Beijing and Qingdao].

    Science.gov (United States)

    Shen, Qing; Jiang, Tao; Li, Nan; Wang, Jiahui; Han, Chunhui; Zhang, Jing; Xu, Jin; Zhang, Dongfeng; Li, Fengqin

    2014-11-01

    The roasted fish fillet sample at the retail collected in Beijing and Qingdao were detected for TTX, and the TTX positive samples was analyzed for fish species identification. TTX was tested by EUSA method and the cytochrome c oxidase I (COI) genome of TTX-positive samples was extracted and identified by DNA barcode. Totally, 90 samples were tested by EUSA and 58 (64.4%) samples were positive for TTX with the levels ranging from 0.10 mg/kg to 63.81 mg/kg. Among the TTX positive samples, 24 (41.3%) were identified containing toxic puffer fish and 21 (87.5%) were Lagocephalus lunaris, the highly toxic puffer fish. Some roasted fish fillet samples obtained from the retail in two cities were positive for TTX and contained toxic puffer fish. Based on these results, we suggest that roasted fish fillet producers should prevent toxic puffer fish from mixing in the raw material and the I regulators should strengthen the TTX surveillance and product labeling supervision of roasted fish fillet.

  16. Heavy metals in commercial fish in New Jersey

    International Nuclear Information System (INIS)

    Burger, Joanna; Gochfeld, Michael

    2005-01-01

    Levels of contaminants in fish are of particular interest because of the potential risk to humans who consume them. While attention has focused on self-caught fish, most of the fish eaten by the American public comes from commercial sources. We sampled 11 types of fish and shellfish obtained from supermarkets and specialty fish markets in New Jersey and analyzed them for arsenic, cadmium, chromium, lead, manganese, mercury, and selenium. We test the null hypothesis that metal levels do not vary among fish types, and we consider whether the levels of any metals could harm the fish themselves or their predators or pose a health risk for human consumers. There were significant interspecific differences for all metals, and no fish types had the highest levels of more than two metals. There were few significant correlations (Kendall tau) among metals for the three most numerous fish (yellowfin tuna, bluefish, and flounder), the correlations were generally low (below 0.40), and many correlations were negative. Only manganese and lead positively were correlated for tuna, bluefish, and flounder. The levels of most metals were below those known to cause adverse effects in the fish themselves. However, the levels of arsenic, lead, mercury, and selenium in some fish were in the range known to cause some sublethal effects in sensitive predatory birds and mammals and in some fish exceeded health-based standards. The greatest risk from different metals resided in different fish; the species of fish with the highest levels of a given metal sometimes exceeded the human health guidance or standards for that metal. Thus, the risk information given to the public (mainly about mercury) does not present a complete picture. The potential of harm from other metals suggests that people not only should eat smaller quantities of fish known to accumulate mercury but also should eat a diversity of fish to avoid consuming unhealthy quantities of other heavy metals. However, consumers should

  17. Fish innate immunity against intestinal helminths.

    Science.gov (United States)

    Dezfuli, B S; Bosi, G; DePasquale, J A; Manera, M; Giari, L

    2016-03-01

    Most individual fish in farmed and wild populations are infected with parasites. Upon dissection of fish, helminths from gut are often easily visible. Enteric helminths include several species of digeneans, cestodes, acanthocephalans and nematodes. Some insights into biology, morphology and histopathological effects of the main fish enteric helminths taxa will be described here. The immune system of fish, as that of other vertebrates, can be subdivided into specific and aspecific types, which in vivo act in concert with each other and indeed are interdependent in many ways. Beyond the small number of well-described models that exist, research focusing on innate immunity in fish against parasitic infections is lacking. Enteric helminths frequently cause inflammation of the digestive tract, resulting in a series of chemical and morphological changes in the affected tissues and inducing leukocyte migration to the site of infection. This review provides an overview on the aspecific defence mechanisms of fish intestine against helminths. Emphasis will be placed on the immune cellular response involving mast cells, neutrophils, macrophages, rodlet cells and mucous cells against enteric helminths. Given the relative importance of innate immunity in fish, and the magnitude of economic loss in aquaculture as a consequence of disease, this area deserves considerable attention and support. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Bacterial spoilage profiles to identify irradiated fish

    International Nuclear Information System (INIS)

    Alur, M.D.; Venugopal, V.; Nerkar, D.P.; Nair, P.M.

    1991-01-01

    Effects of low dose gamma-irradiation of fish product on spoilage potentials of bacteria (Aeromonas hydrophila, Salmonella typhimurium, Bacillus megaterium, and Pseudomonas marinoglutinosa) and mixed flora were examined for ability to proliferate in radurized fish and produce volatile acids (TVA) and bases (TVBN). Bacteria proliferated well in unirradiated and irradiated fish, but formation of VA and VB were lower in irradiated than unirradiated counterparts. This was found in Bombay duck, Indian mackerel, white pomfret, seer and shrimp gamma-irradiated at 0 to 5 kGy under ice. TVA and TVBN produced by the organisms or mixed flora from fish were only 30-50% those of controls. A method for identifying radiation-processed fish could evolve based on lower susceptibility of irradiated fish to bacterial spoilage

  19. Swimming activity in marine fish.

    Science.gov (United States)

    Wardle, C S

    1985-01-01

    Marine fish are capable of swimming long distances in annual migrations; they are also capable of high-speed dashes of short duration, and they can occupy small home territories for long periods with little activity. There is a large effect of fish size on the distance fish migrate at slow swimming speeds. When chased by a fishing trawl the effect of fish size on swimming performance can decide their fate. The identity and thickness of muscle used at each speed and evidence for the timing of myotomes used during the body movement cycle can be detected using electromyogram (EMG) electrodes. The cross-sectional area of muscle needed to maintain different swimming speeds can be predicted by relating the swimming drag force to the muscle force. At maximum swimming speed one completed cycle of swimming force is derived in sequence from the whole cross-sectional area of the muscles along the two sides of the fish. This and other aspects of the swimming cycle suggest that each myotome might be responsible for generating forces involved in particular stages of the tail sweep. The thick myotomes at the head end shorten during the peak thrust of the tail blade whereas the thinner myotomes nearer the tail generate stiffness appropriate for transmission of these forces and reposition the tail for the next cycle.

  20. The Gut Microbiota of Marine Fish

    Science.gov (United States)

    Egerton, Sian; Culloty, Sarah; Whooley, Jason; Stanton, Catherine; Ross, R. Paul

    2018-01-01

    The body of work relating to the gut microbiota of fish is dwarfed by that on humans and mammals. However, it is a field that has had historical interest and has grown significantly along with the expansion of the aquaculture industry and developments in microbiome research. Research is now moving quickly in this field. Much recent focus has been on nutritional manipulation and modification of the gut microbiota to meet the needs of fish farming, while trying to maintain host health and welfare. However, the diversity amongst fish means that baseline data from wild fish and a clear understanding of the role that specific gut microbiota play is still lacking. We review here the factors shaping marine fish gut microbiota and highlight gaps in the research. PMID:29780377

  1. [Ciguatera fish poisoning].

    Science.gov (United States)

    Oehler, Erwan; Bouchut, Jérémie

    2014-09-01

    Ciguatera, an ichtyosarcotoxism linked to the consumption of usually healthy coral fish is a common poisoning in the Pacific, Caribbean and Indian Ocean where it is endemic. However, increased tourism and commercial transportation of tropical fish for consumption make it an unexceptional intoxication in countries away from its endemic area. Environmental stresses such as climate changes also contribute to the expansion of its geographical area. The non-specific clinical symptomatology is characterized by the occurrence of gastrointestinal, cardiovascular, nervous and general signs few hours after eating a ciguatoxic fish. The diagnosis is clinical and relatively easy in endemic areas but much less for physicians who are rarely confronted with, which is a source of prolonged diagnostic delays and a significant increase in spending. Treatment of ciguatera is symptomatic but new treatments, still experimental, give a real hope for the future. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  2. Flushing and pruritus secondary to prescription fish oil ingestion in a patient with allergy to fish.

    Science.gov (United States)

    Howard-Thompson, Amanda; Dutton, Anna; Hoover, Robert; Goodfred, Jennifer

    2014-12-01

    A brand of fish oil capsules contains omega-3 fatty acids obtained from several fish sources. Although the manufacturer calls for caution in patients with fish hypersensitivity, insufficient data is available to make a definitive recommendation regarding its use in this population. A patient with documented seafood allergy presented to the emergency department 4 days after the initiation of prescription brand name fish oil capsules complaining of chest tightness, shortness of breath, tingling of upper extremities, flushing, and pruritus that was minimally relieved by excessive nonprescription diphenhydramine administration. During subsequent follow-up, the patient reported that all symptoms had resolved within 5 days of discontinuing the medication and 3 days of disposing of her pillbox and all medications that had come in contact with the fish oil capsules. Due to the patient's allergic history, timing of onset/offset of the reaction, laboratory evidence, and the use of the Naranjo probability scale, prescription fish oil capsules were deemed the probable cause of this patient's pruritus and flushing of the face and trunk. Practitioners and patients should always ensure they have an updated list of allergies within the patient's medical record that includes medications as well as foods and food additives.

  3. Scombroid fish poisoning: an overlooked marine food poisoning.

    Science.gov (United States)

    Wu, M L; Yang, C C; Yang, G Y; Ger, J; Deng, J F

    1997-08-01

    Scombroid fish poisoning is a food-borne chemical intoxication caused by certain spoiled fish that contain a large amount of histamine and some biogenic diamines. It has gradually become a world-wide medical problem and probably is the most common cause of fish poisoning. As the data on the incidents of scombroid fish poisoning in Taiwan remains scarce, we report 2 incidents of scombroid fish poisoning in Northern Taiwan. We collected data of the 2 outbreaks of suspected fish poisoning which were reported to us in 1996. An epidemiological investigation was undertaken. Questionnaire interviews were given to persons who ate lunch in the same cafeteria in outbreak 2. The leftover fish were sent for species identification and toxin analysis. The first incident involving 4 women occurred in March 1996. All cases experienced flush, dizziness, blurred vision and skin rashes after eating lunch. A non-scombroid fish of Makaira with histamine levels as high as 84.13 mg/100 g flesh was implicated in this incident. In August 1996, another incident involving some cases who ate lunch at the same cafeteria were investigated. A total of 146 questionnaires were distributed with a return of 132 questionnaires (90.4%). Fifty-five employees reported positive signs or symptoms; 48 persons who ate fish and 7 women who did not eat fish were ill. Fish was the only food associated with the illness with an attack rate of 73.8% (p < 0.001). The incriminated fish was later identified as a scombroid fish of Euthynnus with a histamine content of 271.9 mg/100 g flesh in 1 leftover piece and 118.5 mg/100 g flesh in another piece. Most cases in these 2 outbreaks received treatment with antihistamines and had rapid and complete recovery. The diagnosis of scombroid fish poisoning could be misdiagnosed as food allergy or bacterial food poisoning if physicians are not aware of such poisoning. The nonspecific but characteristic symptomatology of histamine food poisoning and previous consumption of fish

  4. Production of Fish Hydrolysates Protein From Waste of Fish Carp (Cyprinus Carpio) by Enzymatic Hydrolysis

    OpenAIRE

    Saputra, Dede; Nurhayati, Tati

    2016-01-01

    Fish Protein Hydrolysates (FPH) is the mixed products of polypeptide, dipeptides, and amino acid. It can be produced from materials that contained of protein by acid reaction, base reaction or enzymatic hydrolysis. The objectives of this study were to study the production of FPH from fish carp meat at post rigor phase and viscera by enzymatic hydrolysis, to determine the specific activity of papain enzyme, and to determine the solubility of FPH. Capacity of fish hydrolyzing can be identified ...

  5. Fish production practices and use of aquaculture technologies ...

    African Journals Online (AJOL)

    The study investigated types of improved aquaculture technologies used by the ... fish farmers culture fish in earthen ponds, for commercial and home consumption ... fishes/m2 (98.3%), water quality management (99.1%) and fish ...

  6. 75 FR 20986 - Permits; Foreign Fishing

    Science.gov (United States)

    2010-04-22

    .... Comments on this notice may also be submitted by e-mail to [email protected] . Include in the... engage in fishing consisting solely of transporting fish or fish products at sea from a point within the... that state to a point outside the United States. In addition, Public Law 104-297, section 105(e...

  7. Use of Sound for Fish Protection at Power Facilities : A Historical Perspective of the State of the Art : Phase 1 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Thomas J.

    1994-11-01

    This paper summarizes the current state of the knowledge of fish hearing, i.e., what is known about fish response to sound, and provides a starting place for investigation into the use of sonic behavior modification to help solve pressing problems in the maintenance and recovery of anadromous and resident fish stocks of the Columbia River Basin. The challenge for scientists and engineers is to understand (1) how and what fish hear, and (2) how to use this knowledge to influence fish behavior or to factor fish sensory systems and behavior into the design of fish protection devices at power-production and water-control facilities. The sections that follow are a studied response to this challenge. In many respects, the search for effective and economical ways to modify fish behavior without physical intervention is one of the grails of fish management, particularly (although not exclusively), relative to electric power production. Within the Columbia River Basin and elsewhere, water is put to many uses not conducive to the health of indigenous fish. Irrigation, impoundment, and hydropower production frequently modify the riverine environment to the detriment of indigenous stocks while creating productive environments for competing or predatory species. The mechanisms of impact are numerous. Water project managers, when faced with the need to reduce impacts of their operations on fish health, generally attempt to divert fish from high-risk to lower-risk regions or manage the environment in such a way as to increase the survival prospects of impacted species. Almost without exception, risk reduction is accomplished by using physical barriers of one form or another. Unfortunately, physical barriers at water projects have several drawbacks, e.g., reducing available water flow for energy production and incurring high maintenance costs. In addition, recent studies (Sale et al. 1991) have documented that once these barriers are installed, they are rarely evaluated for

  8. Histamine (Scombroid) Fish Poisoning: a Comprehensive Review.

    Science.gov (United States)

    Feng, Charles; Teuber, Suzanne; Gershwin, M Eric

    2016-02-01

    Histamine fish poisoning, also known as scombroid poisoning, is the most common cause of ichythyotoxicosis worldwide and results from the ingestion of histamine-contaminated fish in the Scombroidae and Scomberesocidae families, including mackerel, bonito, albacore, and skipjack. This disease was first described in 1799 in Britain and re-emerged in the medical literature in the 1950s when outbreaks were reported in Japan. The symptoms associated with histamine fish poisoning are similar to that of an allergic reaction. In fact, such histamine-induced reactions are often misdiagnosed as IgE-mediated fish allergy. Indeed, histamine fish poisoning is still an underrecognized disease. In this review, we discuss the epidemiology, pathophysiology, evaluation, and treatment of scombroid disease. Because more than 80% of fish consumed in the USA is now imported from other countries, the disease is intimately linked with the global fish trade (National Marine Fisheries Service, 2012). Preventing future scombroid outbreaks will require that fishermen, public health officials, restaurant workers, and medical professionals work together to devise international safety standards and increase awareness of the disease. The implications of scombroid poisoning go far beyond that of fish and have broader implications for the important issues of food safety.

  9. What determines fresh fish consumption in Croatia?

    Science.gov (United States)

    Tomić, Marina; Matulić, Daniel; Jelić, Margareta

    2016-11-01

    Although fresh fish is widely available, consumption still remains below the recommended intake levels among the majority of European consumers. The economic crisis affects consumer food behaviour, therefore fresh fish is perceived as healthy but expensive food product. The aim of this study was to determine the factors influencing fresh fish consumption using an expanded Theory of Planned Behaviour (Ajzen, 1991) as a theoretical framework. The survey was conducted on a heterogeneous sample of 1151 Croatian fresh fish consumers. The study investigated the relationship between attitudes, perceived behavioural control, subjective norm, moral obligation, involvement in health, availability, intention and consumption of fresh fish. Structural Equation Modeling by Partial Least Squares was used to analyse the collected data. The results indicated that attitudes are the strongest positive predictor of the intention to consume fresh fish. Other significant predictors of the intention to consume fresh fish were perceived behavioural control, subjective norm, health involvement and moral obligation. The intention to consume fresh fish showed a strong positive correlation with behaviour. This survey provides valuable information for food marketing professionals and for the food industry in general. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Experimental investigation of fish downstream passage and turbine related fish mortality at an innovative hydro power setup

    International Nuclear Information System (INIS)

    Geiger, Franz; Cuchet, Mathilde; Rutschmann, Peter

    2016-01-01

    The fish downstream passage of small fish at the innovative TUM hydro shaft power plant concept was investigated experimentally. The behavior of 1974 inserted individuals of brown trout, grayling, barbel, minnow and bullhead of 45 mm to 220 mm body length was observed in a fully functional test setup which included a 35 kW Kaplan turbine and a horizontal screen with 20 mm bar clearance. The 24 h tests were conducted under nature like conditions whereas the laboratory environment also enabled targeted hydraulic situations and modifications of the bypass during the test series. A recapture rate of the fish of 99% and a subsequent 96 h observation period yielded detailed information about the migration behavior and instant as well as long term mortality. The results reveal the actual passage distribution of small fish between bypass and turbine and the turbine related injury and mortality rates in dependency of fish species, fish length, turbine discharge and bypass arrangement. General trends as well as species specific particularities could be deduced. The work confirms the suitability of the employed experimental approach and the ecological potential of the investigated hydro power plant concept. The behavioral barrier effect of the screen on small fish and the necessary of appropriate downstream migration corridor were proved and quantified. (authors)

  11. PIXE analysis of fish otoliths. Application to fish stock discrimination

    International Nuclear Information System (INIS)

    Arai, Nobuaki; Sakamoto, Wataru; Tateno, Koji; Yoshida, Koji.

    1996-01-01

    PIXE was adopted to analyze trace elements in otoliths of Japanese flounder to discriminate among several local fish stocks. The otoliths were removed from samples caught at five different sea areas along with the coast of the Sea of Japan: Akita, Ishikawa, Kyoto (2 stations), and Fukuoka. Besides calcium as main component, strontium, manganese, and zinc were detected. Especially Sr concentrations were different among 4 areas except between 2 stations in Kyoto. It suggested that the fish in the 2 stations in Kyoto were the same stock differed to the others. (author)

  12. Consumer attitudes on buying fish in Banja Luka

    Directory of Open Access Journals (Sweden)

    Ostojić Aleksandar

    2017-01-01

    Full Text Available The objective of research presented in the paper is to determine the basic parameters affecting the purchase, supply and consumption of fish in the market of the city of Banja Luka (Bosnia and Herzegovina. The survey was conducted on a random sample of 100 respondents. The data were analyzed by univariante (frequency and distribution and two-variant statistical methods and cross-tabulation. The conclusions are that for the purchase of fish, freshness is a primary factor, which is to be expected given the type of product as well as the origin, and price and type of fish. Out of all respondents, 41% said they were not informed enough about the fish as a food, while the remaining 59% said they got information through different media channels. It was found that consumers are generally informed about the importance of fish as a foodstuff through secondary promotion channels, i.e. 'word of mouth'. Consumers in Banja Luka prefer fresh fish, and the most consumed is freshwater fish. As a place of buying fish, both hypermarket and fish shops are equally represented. Factors of purchase may have a major role in creating consumer attitude towards fish and therefore, producers and sellers of fish are recommended too take into account the results of this and similar studies, in order to segment their markets and develop better marketing tools/strategies and thus make better approach of fish consumers to defined market segments.

  13. Domestic sludge and fish pond effluents in the municipality of Pentecoste, Ceará State, Brazil - doi: 10.4025/actascitechnol.v34i4.12004

    Directory of Open Access Journals (Sweden)

    Marcelo Vinícius do Carmo e Sá

    2012-10-01

    Full Text Available The present work aimed to compare the physical and chemical quality of domestic sludge in the city of Pentecoste, State of Ceará, Brazil, to fish pond effluents from the Aquaculture Research Center of the Departamento Nacional de Obras Contras as Secas – DNOCS, located in the same city. The work was carried out in Pentecoste (State of Ceará, Brazil in three sampling campaigns, with 30-day intervals between them. In each campaign, four samples were collected at different points of the following sites: (1 fish pond supply channel from the Aquaculture Research Center (CPAq of the DNOCS; (2 fish pond drainage channel of CPAq/DNOCS; (3 tap water from four homes in Pentecoste; and (4 domestic sludge channel of Pentecoste. In the lab, samples were analyzed for dissolved oxygen, total ammonia, free CO2, nitrite, reactive phosphorus, electric conductivity and chemical oxygen demand (COD, following standard methods. It was concluded that Pentecoste’s domestic sludge has a much stronger eutrophication impact on the receiving water than that caused by the CPAq/DNOCS’s fish pond effluents.

  14. 50 CFR 223.203 - Anadromous fish.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Anadromous fish. 223.203 Section 223.203... Threatened Marine and Anadromous Species § 223.203 Anadromous fish. Available guidance documents cited in the...)(1) of the ESA (16 U.S.C. 1538(a)(1)) relating to endangered species apply to fish with an intact...

  15. Cooperative Search and Rescue with Artificial Fishes Based on Fish-Swarm Algorithm for Underwater Wireless Sensor Networks

    Science.gov (United States)

    Zhao, Wei; Tang, Zhenmin; Yang, Yuwang; Wang, Lei; Lan, Shaohua

    2014-01-01

    This paper presents a searching control approach for cooperating mobile sensor networks. We use a density function to represent the frequency of distress signals issued by victims. The mobile nodes' moving in mission space is similar to the behaviors of fish-swarm in water. So, we take the mobile node as artificial fish node and define its operations by a probabilistic model over a limited range. A fish-swarm based algorithm is designed requiring local information at each fish node and maximizing the joint detection probabilities of distress signals. Optimization of formation is also considered for the searching control approach and is optimized by fish-swarm algorithm. Simulation results include two schemes: preset route and random walks, and it is showed that the control scheme has adaptive and effective properties. PMID:24741341

  16. Cooperative Search and Rescue with Artificial Fishes Based on Fish-Swarm Algorithm for Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wei Zhao

    2014-01-01

    Full Text Available This paper presents a searching control approach for cooperating mobile sensor networks. We use a density function to represent the frequency of distress signals issued by victims. The mobile nodes’ moving in mission space is similar to the behaviors of fish-swarm in water. So, we take the mobile node as artificial fish node and define its operations by a probabilistic model over a limited range. A fish-swarm based algorithm is designed requiring local information at each fish node and maximizing the joint detection probabilities of distress signals. Optimization of formation is also considered for the searching control approach and is optimized by fish-swarm algorithm. Simulation results include two schemes: preset route and random walks, and it is showed that the control scheme has adaptive and effective properties.

  17. Development of forage cryo minced fish technology

    Directory of Open Access Journals (Sweden)

    Titova S. A.

    2017-11-01

    Full Text Available The technology of grinding the frozen fish raw material using the useful model of a piston-type extrusion plant with cold working bodies for fodder minced fish (cryo minced fish feed by the method of cryoextrusion has been developed. The possibility of replacing the standard manufacturing operations (defrosting and subsequent grinding of raw materials to the one (cryoextrusion has been substantiated. The optimal shape of holes of the die for forcing the raw material has been determined in the form of "hourglass", the hole diameter is 7 mm, the length of the process of pushing is 40 s. It has been established that the finished product (cryo minced fish feed has a homogeneous grinding, juicy, crumbly texture, the temperature in the thickness of the product is equal to the temperature of the raw material before processing (–18 °C. The technological scheme of producing the minced fish feed by the method of cryoextrusion has been developed. Researching the chemical composition of fish and feed of mince produced by the traditional and developed methods it has been established that protein content in the cryo minced fish feed remains unchanged. The amino acid composition of cryo minced fish feed has been determined, the amount of essential amino acids is 365.6 mg/g of protein. In the proteins of the cryo minced fish feed methionine has been contained in the minimum quantity (10.0 mg/g protein and in the maximum – serine (155.3 mg/g protein. In the protein of the cryo minced fish feed the only limiting amino acid is methionine. The coefficient of rationality of the cryo minced fish feed whiting is equal to 0.33. The product is not toxic, is not subject to contamination with dangerous microorganisms, has high biological value, contains necessary in animal nutrition mineral elements, the energy value per 100 g of the product is 87 kcal. The combination of the processes of cryoextrusion and lyophilization allows to obtain a new food product with high

  18. Pickering nuclear fish diversion net

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, J.; Lew, A. [Ontario Power Generation, Toronto, Ontario (Canada)

    2013-07-01

    Pickering Fish Diversion Net - An Engineered Environmental Solution that has significantly reduced fish impingement at the Pickering Nuclear Facility. Note: As a recent urgent request/discussed by Mark Elliot, CNE-OPG and Jacques Plourde, CNS.

  19. Seasonal variability of rocky reef fish assemblages: Detecting functional and structural changes due to fishing effects

    Science.gov (United States)

    Henriques, Sofia; Pais, Miguel Pessanha; Costa, Maria José; Cabral, Henrique Nogueira

    2013-05-01

    The present study analyzed the effects of seasonal variation on the stability of fish-based metrics and their capability to detect changes in fish assemblages, which is yet poorly understood despite the general idea that guilds are more resilient to natural variability than species abundances. Three zones subject to different levels of fishing pressure inside the Arrábida Marine Protected Area (MPA) were sampled seasonally. The results showed differences between warm (summer and autumn) and cold (winter and spring) seasons, with the autumn clearly standing out. In general, the values of the metrics density of juveniles, density of invertebrate feeders and density of omnivores increased in warm seasons, which can be attributed to differences in recruitment patterns, spawning migrations and feeding activity among seasons. The density of generalist/opportunistic individuals was sensitive to the effect of fishing, with higher values at zones with the lowest level of protection, while the density of individuals with high commercial value only responded to fishing in the autumn, due to a cumulative result of both juveniles and adults abundances during this season. Overall, this study showed that seasonal variability affects structural and functional features of the fish assemblage and that might influence the detection of changes as a result of anthropogenic pressures. The choice of a specific season, during warm sea conditions after the spawning period (July-October), seems to be more adequate to assess changes on rocky-reef fish assemblages.

  20. Grande Ronde Basin Fish Habitat Enhancement Project : 2007 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McGowan, Vance R.; Morton, Winston H.

    2008-12-30

    On July 1, 1984 the Bonneville Power Administration and the Oregon Department of Fish and Wildlife entered into an intergovernmental contract to initiate fish habitat enhancement work in the Joseph Creek subbasin of the Grande Ronde River Basin in northeast Oregon. In 1985 the Upper and Middle Grande Ronde River, and Catherine Creek subbasins were included in the contract, and in 1996 the Wallowa River subbasin was added. The primary goal of 'The Grande Ronde Basin Fish Habitat Enhancement Project' is to create, protect, and restore riparian and instream habitat for anadromous salmonids, thereby maximizing opportunities for natural fish production within the basin. This project provided for implementation of Program Measure 703 (C)(1), Action Item 4.2 of the Northwest Power Planning Council's Columbia River Basin Fish and Wildlife Program (NPPC, 1987), and continues to be implemented as offsite mitigation for mainstem fishery losses caused by the Columbia River hydro-electric system. All work conducted by the Oregon Department of Fish and Wildlife and partners is on private lands and therefore requires that considerable time be spent developing rapport with landowners to gain acceptance of, and continued cooperation with this program throughout 10-15 year lease periods. Both passive and active restoration treatment techniques are used. Passive regeneration of habitat, using riparian exclosure fencing and alternate water sources are the primary method to restore degraded streams when restoration can be achieved primarily through changes in management. Active restoration techniques using plantings, bioengineering, site-specific instream structures, or whole stream channel alterations are utilized when streams are more severely degraded and not likely to recover in a reasonable timeframe. Individual projects contribute to and complement ecosystem and basin-wide watershed restoration efforts that are underway by state, federal, and tribal agencies, and

  1. Fish movement ecology in high gradient headwater streams: Its relevance to fish passage restoration through stream culvert barriers

    Science.gov (United States)

    Hoffman, Robert L.; Dunham, Jason B.

    2007-01-01

    Restoration of fish passage through culvert barriers has emerged as a major issue in the Pacific Northwest and nationwide, in part, because of their potential influence on fish movement. Movement is an essential mechanism by which mobile animals acquire the resources necessary for the successful completion of their life-cycles. In this report, we provide a brief review of some essential characteristics of animal movement and examples from a focal group of fishes in Washington State: salmon, trout, and char. We begin by outlining some basic characteristics of animal movement and then apply that foundation to the case of salmonid fishes. Next we consider the consequences of disrupting fish movement with human-constructed barriers, such as culverts. Finally, this body of evidence is summarized, and we propose a short list of what we view as high priority information needs to support more effective restoration of fish passage through culverts.

  2. Ecological role of bluefin tuna (Thunnus thynnus) fish farms for associated wild fish assemblages in the Mediterranean Sea.

    Science.gov (United States)

    Stagličić, Nika; Šegvić-Bubić, Tanja; Ugarković, Pero; Talijančić, Igor; Žužul, Iva; Tičina, Vjekoslav; Grubišić, Leon

    2017-12-01

    The ecological effects of tuna fish farms are largely undocumented. This study confirmed their high capacity to attract surrounding wild fish. The aggregation effect persisted year round, without detectable seasonal differences. Farm impact was restricted to close proximity of the sea cages, and was more prominent over the bottom than in the water column strata. Tuna fish farms proved to be high energy trophic resources, as indicated by the enhanced fitness status of two focal species, bogue and seabream. Under abundant food supply, seabream appear to allocate the majority of energy reserves to gonad development. Farm associated bogue had greater parasite loads, with no detrimental effect on fitness status. Overall, tuna fish farms can be regarded as population sources for aggregated wild fish, and under the no fishing conditions within the leasehold areas, can serve as functional marine protected areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Fish Passage Center 2000 annual report.; ANNUAL

    International Nuclear Information System (INIS)

    Fish Passage Center

    2001-01-01

    The year 2000 hydrosystem operations illustrated two main points: (1) that the NMFS Biological Opinion on the operations of the Federal Columbia River Power System (FCRPS) fish migration measures could not be met in a slightly below average water year, and; (2) the impacts and relationships of energy deregulation and volatile wholesale energy prices on the ability of the FCRPS to provide the Biological Opinion fish migration measures. In 2000, a slightly below average water year, the flow targets were not met and, when energy ''emergencies'' were declared, salmon protection measures were reduced. The 2000 migration year was a below average runoff volume year with an actual run off volume of 61.1 MAF or 96% of average. This year illustrated the ability of the hydro system to meet the migration protection measures established by the NMFS Biological Opinion. The winter operation of storage reservoirs was based upon inaccurate runoff volume forecasts which predicted a January-July runoff volume forecast at The Dalles of 102 to 105% of average, from January through June. Reservoir flood control drafts during the winter months occurred according to these forecasts. This caused an over-draft of reservoirs that resulted in less volume of water available for fish flow augmentation in the spring and the summer. The season Biological Opinion flow targets for spring and summer migrants at Lower Granite and McNary dams were not met. Several power emergencies were declared by BPA in the summer of 2000. The first in June was caused by loss of resources (WNP2 went off-line). The second and third emergencies were declared in August as a result of power emergencies in California and in the Northwest. The unanticipated effects of energy deregulation, power market volatility and rising wholesale electricity prices, and Californian energy deregulation reduced the ability of the FCRPS to implement fish protection measures. A Spill Plan Agreement was implemented in the FCRPS. Under this

  4. Endangered river fish: factors hindering conservation and restoration

    Science.gov (United States)

    Cooke, Steven J.; Paukert, Craig P.; Hogan, Zeb

    2012-01-01

    Globally, riverine fish face many anthropogenic threats including riparian and flood plain habitat degradation, altered hydrology, migration barriers, fisheries exploitation, environmental (climate) change, and introduction of invasive species. Collectively, these threats have made riverine fishes some of the most threatened taxa on the planet. Although much effort has been devoted to identifying the threats faced by river fish, there has been less effort devoted to identifying the factors that may hinder our ability to conserve and restore river fish populations and their watersheds. Therefore, we focus our efforts on identifying and discussing 10 general factors (can also be viewed as research and implementation needs) that constrain or hinder effective conservation action for endangered river fish: (1) limited basic natural history information; (2) limited appreciation for the scale/extent of migrations and the level of connectivity needed to sustain populations; (3) limited understanding of fish/river-flow relationships; (4) limited understanding of the seasonal aspects of river fish biology, particularly during winter and/or wet seasons; (5) challenges in predicting the response of river fish and river ecosystems to both environmental change and various restoration or management actions; (6) limited understanding of the ecosystem services provided by river fish; (7) the inherent difficulty in studying river fish; (8) limited understanding of the human dimension of river fish conservation and management; (9) limitations of single species approaches that often fail to address the broader-scale problems; and (10) limited effectiveness of governance structures that address endangered river fish populations and rivers that cross multiple jurisdictions. We suggest that these issues may need to be addressed to help protect, restore, or conserve river fish globally, particularly those that are endangered.

  5. LCA of Danish fish products

    DEFF Research Database (Denmark)

    Thrane, Mikkel

    2006-01-01

    The article presents the main results from a PhD dissertation about environmental impacts from Danish fish products.......The article presents the main results from a PhD dissertation about environmental impacts from Danish fish products....

  6. Childhood Fish Consumption and Learning and Behavioral Disorders

    Directory of Open Access Journals (Sweden)

    Jenny L. Carwile

    2016-11-01

    Full Text Available Fish is a major source of nutrients critical for brain development during early life. The importance of childhood fish consumption is supported by several studies reporting associations of n-3 polyunsaturated fatty acid (n-3 PUFA supplementation with better behavior and school performance. However, fish may have a different effect than n-3 PUFA alone due to the neurotoxic effects of methylmercury, a frequent contaminant. We investigated associations of childhood fish consumption with learning and behavioral disorders in birth cohort study of the neurotoxic effects of early life exposure to solvent-contaminated drinking water. Childhood (age 7–12 years fish consumption and learning and behavioral problems were reported in self-administered questionnaires (age 23–41 at questionnaire completion. Fish consumption was not meaningfully associated with repeating a grade, tutoring, attending summer school, special class placement, or low educational attainment. However, participants who ate fish several times a week had an elevated odds of Attention Deficit Disorder/Attention Deficit Hyperactivity Disorder (odds ratio: 5.2; 95% confidence interval: 1.5–18 compared to participants who did not eat fish. While these findings generally support the safety of the observed level of fish consumption, the absence of a beneficial effect may be attributed to insufficient fish intake or the choice of relatively low n-3 PUFA fish.

  7. The fish parasite Ichthyophthirius multifiliis

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff

    2017-01-01

    Ichthyophthirius multifiliis, the causative agent of white spot disease (ichthyophthiriasis) is a major burden for fish farmers and aquarists globally. The parasite infects the skin and the gills of freshwater fish, which may acquire a protective adaptive immune response against this disease...... and recognition of carcinogenic and environmentally damaging effects the most efficient compounds are prohibited. A continuous search for novel substances, which are highly effective against the parasites and harmless for the fish is ongoing. These compounds should be environmentally friendly and cost...

  8. Does coastal lagoon habitat quality affect fish growth rate and their recruitment? Insights from fishing and acoustic surveys

    Science.gov (United States)

    Brehmer, P.; Laugier, T.; Kantoussan, J.; Galgani, F.; Mouillot, D.

    2013-07-01

    Ensuring the sustainability of fish resources necessitates understanding their interaction with coastal habitats, which is becoming ever more challenging in the context of ever increasing anthropogenic pressures. The ability of coastal lagoons, exposed to major sources of disturbance, to provide resources and suitable habitats for growth and survival of juvenile fish is especially important. We analysed three lagoons with different ecological statuses and habitat quality on the basis of their eutrophication and ecotoxicity (Trix test) levels. Fish abundances were sampled using fishing and horizontal beaming acoustic surveys with the same protocols in the same year. The relative abundance of Anguilla anguilla, Dicentrarchus labrax or the Mugilidae group was not an indicator of habitat quality, whereas Atherina boyeri and Sparus aurata appeared to be more sensitive to habitat quality. Fish abundance was higher in the two lagoons with high eutrophication and ecotoxicity levels than in the less impacted lagoon, while fish sizes were significantly higher in the two most severely impacted lagoons. This leads us to suggest low habitat quality may increase fish growth rate (by the mean of a cascading effect), but may reduce lagoon juvenile abundance by increasing larval mortality. Such a hypothesis needs to be further validated using greater investigations which take into account more influences on fish growth and recruitment in such variable environments under complex multi-stressor conditions.

  9. Temperature - Live Hauling of Fish

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In certain markets, live fish can be sold for substantially higher prices than fresh dressed fish. A significant live-haul industry has developed in the U.S. and...

  10. KLA - Live Hauling of Fish

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In certain markets, live fish can be sold for substantially higher prices than fresh dressed fish. A significant live-haul industry has developed in the U.S. and...

  11. Fish gelatin.

    Science.gov (United States)

    Boran, Gokhan; Regenstein, Joe M

    2010-01-01

    Gelatin is a multifunctional ingredient used in foods, pharmaceuticals, cosmetics, and photographic films as a gelling agent, stabilizer, thickener, emulsifier, and film former. As a thermoreversible hydrocolloid with a narrower gap between its melting and gelling temperatures, both of which are below human body temperature, gelatin provides unique advantages over carbohydrate-based gelling agents. Gelatin is mostly produced from pig skin, and cattle hides and bones. Some alternative raw materials have recently gained attention from both researchers and the industry not just because they overcome religious concerns shared by Jews and Muslims but also because they provide, in some cases, technological advantages over mammalian gelatins. Fish skins from a number of fish species are among the other sources that have been comprehensively studied as sources for gelatin production. Fish skins have a significant potential for the production of high-quality gelatin with different melting and gelling temperatures over a much wider range than mammalian gelatins, yet still have a sufficiently high gel strength and viscosity. Gelatin quality is industrially determined by gel strength, viscosity, melting or gelling temperatures, the water content, and microbiological safety. For gelatin manufacturers, yield from a particular raw material is also important. Recent experimental studies have shown that these quality parameters vary greatly depending on the biochemical characteristics of the raw materials, the manufacturing processes applied, and the experimental settings used for quality control tests. In this review, the gelatin quality achieved from different fish species is reviewed along with the experimental procedures used to determine gelatin quality. In addition, the chemical structure of collagen and gelatin, the collagen-gelatin conversion, the gelation process, and the gelatin market are discussed. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. Competition for the fish - fish extraction from the Baltic Sea by humans, aquatic mammals and birds

    DEFF Research Database (Denmark)

    Hansson, Sture; Bergström, Ulf; Bonsdorff, E.

    2018-01-01

    Populations of fish eating mammals (primarily seals) and birds have increased in the Baltic Sea and there is concern that their consumption reduces fish stocks and has negative impact on the fishery. Based primarily on published data on fisheries’ landings and abundances, consumption and diets...... to be addressed in basic ecosystem research, management and conservation. This requires improved quantitative data on wildlife diets, abundances and fish production...... of birds and seals around year 2010, we compare consumption of commercial fish species by seals (1*105 metric tons per year) and birds (1*105 tons) to the catch in the commercial and recreational fishery (7*105 tons), and when applicable at the geographical resolution of ICES subdivisions. The large...

  13. The consequences of balanced harvesting of fish communities

    DEFF Research Database (Denmark)

    Jacobsen, Nis Sand; Gislason, Henrik; Andersen, Ken Haste

    2014-01-01

    community structure and yield. We use a size- and trait-based model that resolves individual interactions through competition and predation to compare balanced harvesting with traditional selective harvesting, which protects juvenile fish from fishing. Four different exploitation patterns, generated......Balanced harvesting, where species or individuals are exploited in accordance with their productivity, has been proposed as a way to minimize the effects of fishing on marine fish communities and ecosystems. This calls for a thorough examination of the consequences balanced harvesting has on fish...... by combining selective or unselective harvesting with balanced or unbalanced fishing, are compared. We find that unselective balanced fishing, where individuals are exploited in proportion to their productivity, produces a slightly larger total maximum sustainable yield than the other exploitation patterns and...

  14. Coastal Resources Atlas: Long Island: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species for Long Island, New York. Vector polygons...

  15. Evaluation of Application Space Expansion for the Sensor Fish

    Energy Technology Data Exchange (ETDEWEB)

    DeRolph, Christopher R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevelhimer, Mark S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-02-01

    The Pacific Northwest National Laboratory has developed an instrument known as the sensor fish that can be released into downstream passage routes at hydropower facilities to collect data on the physical conditions that a fish might be exposed to during passage through a turbine. The US Department of Energy Wind and Water Power Program sees value in expanding the sensor fish application space beyond large Kaplan turbines in the northwest United States to evaluate conditions to which a greater variety of fish species are exposed. Development of fish-friendly turbines requires an understanding of both physical passage conditions and biological responses to those conditions. Expanding the use of sensor fish into other application spaces will add to the knowledge base of physical passage conditions and could also enhance the use of sensor fish as a site-specific tool in mitigating potential impacts to fish populations from hydropower. The Oak Ridge National Laboratory (ORNL) National Hydropower Assessment Program (NHAAP) database contains hydropower facility characteristics that, along with national fish distribution data, were used to evaluate potential interactions between fish species and project characteristics related to downstream passage issues. ORNL developed rankings for the turbine types in the NHAAP database in terms of their potential to impact fish through injury or mortality during downstream turbine passage. National-scale fish distributions for 31 key migratory species were spatially intersected with hydropower plant locations to identify facilities where turbines with a high threat to fish injury or mortality overlap with the potential range of a sensitive fish species. A dataset was produced that identifies hydropower facilities where deployment of the sensor fish technology might be beneficial in addressing issues related to downstream fish passage. The dataset can be queried to target specific geographic regions, fish species, license expiration

  16. The Miocene fish Marosichthys, a putative tetraodontiform, actually a perciform surgeon fish (Acanthuridae) related to the recent Naso

    NARCIS (Netherlands)

    Tyler, James C.

    1997-01-01

    Marosichthys huismani (de Beaufort, 1926), a fish from the Miocene of the Celebes, was described in the tripod fish family Triacanthidae, Tetraodontiformes. It is shown here to be a valid genus of the surgeon fish family Acanthuridae, Perciformes, and closely related to the Recent genus Naso.

  17. Biofilm responses to marine fish farm wastes

    Energy Technology Data Exchange (ETDEWEB)

    Sanz-Lazaro, Carlos, E-mail: carsanz@um.es [Departamento de Ecologia e Hidrologia, Facultad de Biologia, Universidad de Murcia, 30100 Murcia (Spain); Navarrete-Mier, Francisco; Marin, Arnaldo [Departamento de Ecologia e Hidrologia, Facultad de Biologia, Universidad de Murcia, 30100 Murcia (Spain)

    2011-03-15

    The changes in the biofilm community due to organic matter enrichment, eutrophication and metal contamination derived from fish farming were studied. The biofilm biomass, polysaccharide content, trophic niche and element accumulation were quantified along an environmental gradient of fish farm wastes in two seasons. Biofilm structure and trophic diversity was influenced by seasonality as well as by the fish farm waste load. Fish farming enhanced the accumulation of organic carbon, nutrients, selenium and metals by the biofilm community. The accumulation pattern of these elements was similar regardless of the structure and trophic niche of the community. This suggests that the biofilm communities can be considered a reliable tool for assessing dissolved aquaculture wastes. Due to the ubiquity of biofilms and its wide range of consumers, its role as a sink of dissolved wastes may have important implications for the transfer of aquaculture wastes to higher trophic levels in coastal systems. - Research highlights: > Biofilms can act as a trophic pathway of fish farm dissolved wastes. > Biofilms are reliable tools for monitoring fish farm dissolved wastes. > The influence of the fish farm dissolved wastes can be detected 120-350 m from farm. - Under the influence of fish farming biofilm accumulates organic carbon, nutrients, selenium and metals, regardless of the structure and trophic niche of the community.

  18. Who cares about fish welfare?

    DEFF Research Database (Denmark)

    Ellingsen, Kristian; Grimsrud, Kristine; Nielsen, Hanne Marie

    2015-01-01

    . Research limitations/implications – In this study willingness to pay is measured using a hypothetical choice experiment. Values people express as citizens, however, may not accurately predict true consumer behaviour. This is generally referred to as “citizen-consumer duality” and may have affected...... about the appropriate way to pay for better welfare standards in fish production. Design/methodology/approach – On the basis of two focus group sessions, a survey questionnaire was developed and distributed to a representative sample of 2,147 Norwegian households via e-mail. Findings – Results showed...... the results. Practical implications – The study shows that there is a national market for welfare-assured fish products, but education initiatives focusing on fish farming and fish welfare issues would further influence the attitudes and purchasing habits of Norwegian consumers. Originality/value – Although...

  19. Enviromental contaminants in Puget Sound fish - Histological Preparation and Chemical Analyses of Puget Sound Fish

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — As part of a long-term contaminant-monitoring program of fish in Puget Sound and Georgia Basin, Washington Department of Fish and Wildlife (WDFW) and NWFSC have...

  20. Larvivorous fish for preventing malaria transmission

    Science.gov (United States)

    Walshe, Deirdre P; Garner, Paul; Adeel, Ahmed A; Pyke, Graham H; Burkot, Thomas R

    2017-01-01

    Background Adult female Anopheles mosquitoes can transmit Plasmodium parasites that cause malaria. Some fish species eat mosquito larvae and pupae. In disease control policy documents, the World Health Organization (WHO) includes biological control of malaria vectors by stocking ponds, rivers, and water collections near where people live with larvivorous fish to reduce Plasmodium parasite transmission. In the past, the Global Fund has financed larvivorous fish programmes in some countries, and, with increasing efforts in eradication of malaria, policymakers may return to this option. Therefore, we assessed the evidence base for larvivorous fish programmes in malaria control. Objectives To evaluate whether introducing larvivorous fish to anopheline larval habitats impacts Plasmodium parasite transmission. We also sought to summarize studies that evaluated whether introducing larvivorous fish influences the density and presence of Anopheles larvae and pupae in water sources. Search methods We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; MEDLINE (PubMed); Embase (Ovid); CABS Abstracts; LILACS; and the metaRegister of Controlled Trials (mRCT) up to 6 July 2017. We checked the reference lists of all studies identified by the search. We examined references listed in review articles and previously compiled bibliographies to look for eligible studies. Also we contacted researchers in the field and the authors of studies that met the inclusion criteria for additional information regarding potential studies for inclusion and ongoing studies. This is an update of a Cochrane Review published in 2013. Selection criteria Randomized controlled trials (RCTs) and non-RCTs, including controlled before-and-after studies, controlled time series, and controlled interrupted time series studies from malaria-endemic regions that introduced fish as a larvicide and