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Sample records for albacore tuna thunnus

  1. How important are coastal fronts to albacore tuna (Thunnus alalunga) habitat in the Northeast Pacific Ocean?

    NASA Astrophysics Data System (ADS)

    Nieto, Karen; Xu, Yi; Teo, Steven L. H.; McClatchie, Sam; Holmes, John

    2017-01-01

    We used satellite sea surface temperature (SST) data to characterize coastal fronts and then tested the effects of the fronts and other environmental variables on the distribution of the albacore tuna (Thunnus alalunga) catches in the coastal areas (from the coast to 200 nm offshore) of the Northeast Pacific Ocean. A boosted regression tree (BRT) model was used to explain the spatial and temporal patterns in albacore tuna catch per unit effort (CPUE) (1988-2011), using frontal features (distance to the front and temperature gradient), and other environmental variables like SST, surface chlorophyll concentration (chlorophyll), and geostrophic currents as explanatory variables. Based on over two decades of high-resolution data, the modeled results confirmed previous findings that albacore CPUE distribution is strongly influenced by SST and chlorophyll at fishing locations, and the distance of fronts from the coast (DFRONT-COAST), albeit with substantial seasonal and interannual variation. Albacore CPUEs were higher near warm, low chlorophyll oceanic waters, and near SST fronts. We performed sequential leave-one-year-out cross-validations for all years and found that the relationships in the BRT models were robust for the entire study period. Spatial distributions of model-predicted albacore CPUE were similar to observations, but the model was unable to predict very high CPUEs in some areas. These results help to explain previously observed variability in albacore CPUE and will likely help improve international fisheries management in the face of environmental changes.

  2. Reproductive Biology of Albacore Tuna (Thunnus alalunga) in the Western Indian Ocean.

    PubMed

    Dhurmeea, Zahirah; Zudaire, Iker; Chassot, Emmanuel; Cedras, Maria; Nikolic, Natacha; Bourjea, Jérôme; West, Wendy; Appadoo, Chandani; Bodin, Nathalie

    2016-01-01

    The reproductive biology of albacore tuna, Thunnus alalunga, in the western Indian Ocean was examined through analysis of the sex ratio, spawning season, length-at-maturity (L50), spawning frequency and fecundity. From 2013 to 2015, a total of 923 female and 867 male albacore were sampled. A bias in sex ratio was found in favor of females with fork length (LF) < 100 cm. Using histological analyses and gonadosomatic index, spawning was found to occur between 10°S and 30°S, mainly to the east of Madagascar from October to January. Large females contributed more to reproduction through their longer spawning period compared to small individuals. The L50 (mean ± standard error) of female albacore was estimated at 85.3 ± 0.7 cm LF. Albacore spawn on average every 2.2 days within the spawning region and spawning months, from November to January. Batch fecundity ranged between 0.26 and 2.09 million oocytes and the relative batch fecundity (mean ± standard deviation) was estimated at 53.4 ± 23.2 oocytes g-1 of somatic-gutted weight. The study provides new information on the reproductive development and classification of albacore in the western Indian Ocean. The reproductive parameters will reduce uncertainty in current stock assessment models which will eventually assist the fishery to be sustainable for future generations.

  3. Reproductive Biology of Albacore Tuna (Thunnus alalunga) in the Western Indian Ocean

    PubMed Central

    Dhurmeea, Zahirah; Zudaire, Iker; Chassot, Emmanuel; Cedras, Maria; Nikolic, Natacha; Bourjea, Jérôme; West, Wendy; Appadoo, Chandani

    2016-01-01

    The reproductive biology of albacore tuna, Thunnus alalunga, in the western Indian Ocean was examined through analysis of the sex ratio, spawning season, length-at-maturity (L50), spawning frequency and fecundity. From 2013 to 2015, a total of 923 female and 867 male albacore were sampled. A bias in sex ratio was found in favor of females with fork length (LF) < 100 cm. Using histological analyses and gonadosomatic index, spawning was found to occur between 10°S and 30°S, mainly to the east of Madagascar from October to January. Large females contributed more to reproduction through their longer spawning period compared to small individuals. The L50 (mean ± standard error) of female albacore was estimated at 85.3 ± 0.7 cm LF. Albacore spawn on average every 2.2 days within the spawning region and spawning months, from November to January. Batch fecundity ranged between 0.26 and 2.09 million oocytes and the relative batch fecundity (mean ± standard deviation) was estimated at 53.4 ± 23.2 oocytes g-1 of somatic-gutted weight. The study provides new information on the reproductive development and classification of albacore in the western Indian Ocean. The reproductive parameters will reduce uncertainty in current stock assessment models which will eventually assist the fishery to be sustainable for future generations. PMID:28002431

  4. Vertical behavior and diet of albacore tuna (Thunnus alalunga) vary with latitude in the South Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Williams, Ashley J.; Allain, Valerie; Nicol, Simon J.; Evans, Karen J.; Hoyle, Simon D.; Dupoux, Cyndie; Vourey, Elodie; Dubosc, Jeff

    2015-03-01

    Albacore tuna (Thunnus alalunga) are an important upper tropic-level oceanic predator with a circum-global distribution. Little is known of the movements and diet of albacore tuna in the South Pacific Ocean and how variability in both might influence the vulnerability of albacore tuna to fisheries across their range. We coupled data derived from satellite-tagged albacore tuna with stomach samples collected from individuals at the same locations to characterize the vertical behavior, thermal and dietary habits of albacore tuna at tropical (New Caledonia and Tonga) and temperate (New Zealand) latitudes. A total of 18 pop-up satellite archival tags deployed on albacore tuna remained attached for 0-50 days. Position estimates, calculated from 11 tags, described short-term movements of predominantly less than 500 km, although one fish moved more than 1000 km over a period of 50 days. Vertical behavior and diet differed substantially between tropical and temperate latitudes. At tropical latitudes, albacore tuna showed a distinct diel pattern in vertical habitat use, occupying shallower, warmer waters above the mixed layer depth (MLD) at night, and deeper, cooler waters below the MLD during the day. In contrast, there was little evidence of a diel pattern of vertical behavior in albacore tuna at temperate latitudes, with fish limited to shallow waters above the MLD almost all of the time. Spatial patterns of species composition in stomach contents were consistent with vertical movement patterns, with significantly more deepwater prey species consumed in tropical waters than in temperate waters. Albacore in tropical waters also consumed significantly greater diversities of prey than in temperate waters, predominately preying on fish species, whereas those in temperate waters predominately preyed on crustacea. Our results indicate that the vertical distribution of albacore is constrained either by thermal preferences with diet reflecting these preferences, by the vertical

  5. New Nuclear SNP Markers Unravel the Genetic Structure and Effective Population Size of Albacore Tuna (Thunnus alalunga)

    PubMed Central

    Laconcha, Urtzi; Iriondo, Mikel; Arrizabalaga, Haritz; Manzano, Carmen; Markaide, Pablo; Montes, Iratxe; Zarraonaindia, Iratxe; Velado, Igor; Bilbao, Eider; Goñi, Nicolas; Santiago, Josu; Domingo, Andrés; Karakulak, Saadet; Oray, Işık; Estonba, Andone

    2015-01-01

    In the present study we have investigated the population genetic structure of albacore (Thunnus alalunga, Bonnaterre 1788) and assessed the loss of genetic diversity, likely due to overfishing, of albacore population in the North Atlantic Ocean. For this purpose, 1,331 individuals from 26 worldwide locations were analyzed by genotyping 75 novel nuclear SNPs. Our results indicated the existence of four genetically homogeneous populations delimited within the Mediterranean Sea, the Atlantic Ocean, the Indian Ocean and the Pacific Ocean. Current definition of stocks allows the sustainable management of albacore since no stock includes more than one genetic entity. In addition, short- and long-term effective population sizes were estimated for the North Atlantic Ocean albacore population, and results showed no historical decline for this population. Therefore, the genetic diversity and, consequently, the adaptive potential of this population have not been significantly affected by overfishing. PMID:26090851

  6. New Nuclear SNP Markers Unravel the Genetic Structure and Effective Population Size of Albacore Tuna (Thunnus alalunga).

    PubMed

    Laconcha, Urtzi; Iriondo, Mikel; Arrizabalaga, Haritz; Manzano, Carmen; Markaide, Pablo; Montes, Iratxe; Zarraonaindia, Iratxe; Velado, Igor; Bilbao, Eider; Goñi, Nicolas; Santiago, Josu; Domingo, Andrés; Karakulak, Saadet; Oray, Işık; Estonba, Andone

    2015-01-01

    In the present study we have investigated the population genetic structure of albacore (Thunnus alalunga, Bonnaterre 1788) and assessed the loss of genetic diversity, likely due to overfishing, of albacore population in the North Atlantic Ocean. For this purpose, 1,331 individuals from 26 worldwide locations were analyzed by genotyping 75 novel nuclear SNPs. Our results indicated the existence of four genetically homogeneous populations delimited within the Mediterranean Sea, the Atlantic Ocean, the Indian Ocean and the Pacific Ocean. Current definition of stocks allows the sustainable management of albacore since no stock includes more than one genetic entity. In addition, short- and long-term effective population sizes were estimated for the North Atlantic Ocean albacore population, and results showed no historical decline for this population. Therefore, the genetic diversity and, consequently, the adaptive potential of this population have not been significantly affected by overfishing.

  7. Maturity Ogives for South Pacific Albacore Tuna (Thunnus alalunga) That Account for Spatial and Seasonal Variation in the Distributions of Mature and Immature Fish

    PubMed Central

    Farley, Jessica H.; Hoyle, Simon D.; Eveson, J. Paige; Williams, Ashley J.; Davies, Campbell R.; Nicol, Simon J.

    2014-01-01

    Length and age at maturity are important life history parameters for estimating spawning stock biomass and reproductive potential of fish stocks. Bias in estimates of size and age at maturity can arise when disparate distributions of mature and immature fish within a population are not accounted for in the analysis. Here we investigate the spatial and temporal variability in observed size and age at maturity of female albacore tuna, Thunnus alalunga, using samples collected across the South Pacific. Maturity status was identified using consistent histological criteria that were precise enough to allow for mature but regenerating females to be distinguished from immature females during the non-spawning season, permitting year-round sampling for maturity estimation in albacore. Using generalised linear mixed models, we found that the proportion of mature females at length varied significantly with latitude and time of year. Specifically, females at northern latitudes (∼10–20°S, where spawning occurs) were mature at significantly smaller lengths and ages than females at southern latitudes (∼20–40°S), particularly during the spawning season (October–March). This variation was due to different geographic distributions of mature and immature fish during the year. We present a method for estimating an unbiased maturity ogive that takes into account the latitudinal variation in proportion mature at length during a given season (spawning or non-spawning). Applying this method to albacore samples from the western region of the South Pacific gave a predicted length at 50% mature of ∼87 cm fork length (4.5 years). PMID:24416153

  8. Influence of fronts on the spatial distribution of albacore tuna (Thunnus alalunga) in the Northeast Pacific over the past 30 years (1982-2011)

    NASA Astrophysics Data System (ADS)

    Xu, Yi; Nieto, Karen; Teo, Steven L. H.; McClatchie, Sam; Holmes, John

    2017-01-01

    The association of albacore tuna distribution with subtropical fronts in the Northeast Pacific was examined on seasonal and interannual scales from 1982 to 2011. Spatial analyses were performed on commercial logbook data from US and Canadian troll and pole-and-line fisheries targeting albacore tuna that were matched with corresponding satellite images from the Advanced Very High Resolution Radiometer (AVHRR). Subtropical fronts were detected by deriving sea surface temperature (SST) gradients on large basin-scales and by using an improved version of the Cayula-Cornillon frontal detection algorithm. Based on our results, we suggest that areas with high albacore catch-per-unit-effort (CPUE) tend to occur in regions with high SST gradients, such as the North Pacific Transition Zone (NPTZ) and the North American coast. Approaching the North American coast along the NPTZ, SST gradients drop off substantially around 130°W before increasing rapidly near the coast, which corresponded to a similar pattern in albacore CPUE. In the NPTZ, the centroid of albacore CPUE showed a seasonal shift northwards in summer and southwards in fall, which coincided with seasonal spatial shifts of areas with high SST gradients. A similar pattern was found on an interannual scale, with the exception of several years with limited fishery data in the NPTZ due to changes in fishery operations. A fine-scale analysis of frontal locations suggested that areas with high albacore CPUE are associated with oceanic fronts, with the highest albacore CPUEs observed within 100 km of the nearest front. In addition, albacore distribution is related to frontal strength, with the highest CPUE found near fronts with high SST gradient values in the range of 0.12-0.16 °C km-1. Integrating our findings on the influence of frontal areas on albacore distribution and abundance in the NEPO should improve the standardization model used to derive abundance indices for North Pacific albacore stock assessments.

  9. Draft Genome Sequences of Histamine-Producing Photobacterium kishitanii and Photobacterium angustum, Isolated from Albacore (Thunnus alalunga) and Yellowfin (Thunnus albacares) Tuna

    PubMed Central

    McCarthy, Susan A.; Dunlap, Paul V.; Timme, Ruth E.; Benner, Ronald A.

    2015-01-01

    Histamine-producing bacteria are responsible for scombrotoxin (histamine) fish poisoning, a leading cause of fish poisoning in the United States. We report here the draft genome sequences of four histamine-producing (HP) Photobacterium kishitanii strains and nine HP Photobacterium angustum strains isolated from tuna. PMID:25931609

  10. A continuous time delay-difference type model (CTDDM) applied to stock assessment of the southern Atlantic albacore Thunnus alalunga

    NASA Astrophysics Data System (ADS)

    Liao, Baochao; Liu, Qun; Zhang, Kui; Baset, Abdul; Memon, Aamir Mahmood; Memon, Khadim Hussain; Han, Yanan

    2016-09-01

    A continuous time delay-diff erence model (CTDDM) has been established that considers continuous time delays of biological processes. The southern Atlantic albacore ( Thunnus alalunga) stock is the one of the commercially important tuna population in the marine world. The age structured production model (ASPM) and the surplus production model (SPM) have already been used to assess the albacore stock. However, the ASPM requires detailed biological information and the SPM lacks the biological realism. In this study, we focus on applying a CTDDM to the southern Atlantic albacore ( T. alalunga) species, which provides an alternative method to assess this fishery. It is the first time that CTDDM has been provided for assessing the Atlantic albacore ( T. alalunga) fishery. CTDDM obtained the 80% confidence interval of MSY (maximum sustainable yield) of (21 510 t, 23 118t). The catch in 2011 (24 100 t) is higher than the MSY values and the relative fishing mortality ratio ( F 2011/ F MSY) is higher than 1.0. The results of CTDDM were analyzed to verify the proposed methodology and provide reference information for the sustainable management of the southern Atlantic albacore stock. The CTDDM treats the recruitment, the growth, and the mortality rates as all varying continuously over time and fills gaps between ASPM and SPM in this stock assessment.

  11. Modelling the impact of climate change on South Pacific albacore tuna

    NASA Astrophysics Data System (ADS)

    Lehodey, Patrick; Senina, Inna; Nicol, Simon; Hampton, John

    2015-03-01

    The potential impact of climate change under the IPCC AR4-A2 scenario (close to the AR5-RCP8.5 scenario) on south Pacific albacore tuna (Thunnus alalunga) is simulated with the Spatial Ecosystem And Population Dynamics Model (SEAPODYM) and environmental forcing variables provided by the Earth Climate model IPSL-CM4. Parameters controlling the habitat and dynamics of the population were optimized by fitting the model, using maximum likelihood, to a complete fishing data set for the historical fishing period since 1950. Albacore undertake clear seasonal migrations between feeding and spawning grounds, as evidenced by seasonal catch and size composition changes. This seasonality was well predicted by the SEAPODYM albacore simulations. The total biomass estimate of south Pacific albacore was predicted to have decreased from ~1.8 million tonnes (Mt) at the beginning of industrial fisheries in 1950 to 1.25 Mt in 2006, in good agreement with an independent estimate from stock assessment analysis. A simulation without fishing indicated an equivalent contribution of environmental variability and fishing to the historical decrease of the stock biomass. The parameterized SEAPODYM model was used to project the dynamics of the population until the end of the 21st century with an average fishing effort based on recent years. Under this fishing and climate change scenario, the population was predicted to decrease and to stabilize after 2035 just below 0.8 Mt, i.e., 55% below the initial biomass of 1960. After 2080 however, the trend was reversed when a new spawning ground emerged in the north Tasman Sea. A test simulation highlighted the sensitivity of the model results to projected dissolved oxygen concentration for which there is large uncertainty in the tropical region. A second test simulation showed that genetic selection favouring albacore with preferences for higher optimal ambient spawning temperature would maintain a reduced level of spawning in current tropical spawning

  12. Application of a Delay-difference model for the stock assessment of southern Atlantic albacore ( Thunnus alalunga)

    NASA Astrophysics Data System (ADS)

    Zhang, Kui; Liu, Qun; Kalhoro, Muhsan Ali

    2015-06-01

    Delay-difference models are intermediate between simple surplus-production models and complicated age-structured models. Such intermediate models are more efficient and require less data than age-structured models. In this study, a delay-difference model was applied to fit catch and catch per unit effort (CPUE) data (1975-2011) of the southern Atlantic albacore ( Thunnus alalunga) stock. The proposed delay-difference model captures annual fluctuations in predicted CPUE data better than Fox model. In a Monte Carlo simulation, white noises (CVs) were superimposed on the observed CPUE data at four levels. Relative estimate error was then calculated to compare the estimated results with the true values of parameters α and β in Ricker stock-recruitment model and the catchability coefficient q. a is more sensitive to CV than β and q. We also calculated an 80% percentile confidence interval of the maximum sustainable yield (MSY, 21756 t to 23408 t; median 22490 t) with the delay-difference model. The yield of the southern Atlantic albacore stock in 2011 was 24122 t, and the estimated ratios of catch against MSY for the past seven years were approximately 1.0. We suggest that care should be taken to protect the albacore fishery in the southern Atlantic Ocean. The proposed delay-difference model provides a good fit to the data of southern Atlantic albacore stock and may be a useful choice for the assessment of regional albacore stock.

  13. On the movements, aggregations and the foraging habitat of bluefin tuna (Thunnus thynnus and Thunnus orientalis)

    NASA Astrophysics Data System (ADS)

    Walli, Andreas G.

    To exploit the ocean's patchy resources, large open ocean fish species have evolved highly migratory foraging strategies. In this thesis, a synoptic study of Atlantic bluefin tuna (Thunnus thynnus) and Pacific bluefin tuna (Thunnus orientalis) and their environment was conducted to identify feeding behavior and foraging related horizontal and vertical movements, and to elucidate foraging habitat. First, electronic archival tags (n=561) were used to examine seasonal movements (1996-2005), aggregations and diving behaviors of Atlantic bluefin tuna (ABFT) to better understand their migration ecology and oceanic habitat utilization. Throughout the North Atlantic mean diving depth was significantly correlated with thermocline depth and dive behavior changed in relation to the stratification of the water column. Distribution behavior was characterized by seasonal aggregations and rapid movement phases. Throughout the North Atlantic, high residence times (167 +/- 33 days) were identified in four spatially confined regions on a seasonal scale. In these regions, mean diving depths were significantly shallower and dive frequency and internal temperature variance were significantly higher than during transit movements between the regions, suggesting foraging behavior. Residence time in high-use areas was correlated to primary productivity in northern latitudes and these areas represent critical foraging habitats with seasonally abundant prey. To be able to study feeding in wild bluefin tunas, the heat increment of feeding (HIF) in response to known quantities and caloric value of food ingested by captive individuals was evaluated. Feeding experiments were conducted using stomach and peritoneal placed archival tags in captive Pacific bluefin tuna (PBFT, n=31). Peritoneal temperature measurements indicate a significant correlation between food energy content and the duration from the start of post-grandial heat increment to the maximum thermal excess (TXmax ) in all ambient

  14. Mitochondrial genome of the blackfin tuna Thunnus atlanticus Lesson, 1831 (Perciformes, Scrombidae).

    PubMed

    Márquez, Edna J; Isaza, Juan P; Alzate, Juan F

    2016-05-01

    Blackfin tuna, Thunnus atlanticus is a widespread epipelagic oceanic species in the western Atlantic. So far the mitochondrial genome of this species remained unknown, although the mitogenomes of all congeners are known. The mitochondrial genome encodes for 13 proteins, 21 tRNAs, 2 ribosomal RNAs and the gene synteny is conserved with other previously reported mitogenomes of tunas.

  15. Using stable isotopes of albacore tuna and predictive models to characterize bioregions and examine ecological change in the SW Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Pethybridge, Heidi R.; Young, Jock W.; Kuhnert, Petra M.; Farley, Jessica H.

    2015-05-01

    Broad-scale food web inferences of 534 albacore tuna, Thunnus alalunga, in the south-west Pacific Ocean in 2009 and 2010 were made using bulk nitrogen (δ15N) and carbon (δ13C) stable isotopes. Condition was also examined for the same fish using C:N ratios. A Generalized Additive Modeling (GAM) approach was used to analyze spatio-temporal, biological and environmental drivers that impact the distribution of tuna isotopes and to create oceanographic maps. Based on model formulations, five bioregions with distinct isotopic signatures were identified and were related to known biological, nutrient cycling and oceanographic (temperature, primary productivity and eddy) features associated with the East Australian Current. δ15N values showed a large-scale, uniform latitudinal gradient decreasing from the south to north, in a region encompassing oligotrophic waters in the Coral Sea. In contrast, δ13C values were lower in the nutrient rich Tasman Sea waters and offshore East Australia. C:N ratios suggested that albacore occupying southern and offshore waters were in better condition. Ontogenetic trends in all three biochemical parameters were identified and related to differences in size distribution. Regional-specific temporal variations were detected including similar monthly changes for both isotopes and significantly less enriched δ13C (by 1.9‰) than in previous work undertaken in 2006, potentially signifying a substantial shift in the carbon cycle that supports food webs off central east Australia. Our results showed that isotopic measurements in tuna and the GAM framework provide powerful tools to assess ecosystem functioning and change by linking sources of nutrients and organic matter to local food web assembly. Such knowledge is vital to support an ecosystem based approach to fisheries management including biogeochemical whole-of-ecosystem models and monitoring programs at regional and landscape-scales.

  16. Atlantic Bluefin Tuna (Thunnus thynnus) Biometrics and Condition

    PubMed Central

    Abid, Noureddine; Addis, Piero; Alot, Enrique; Andrushchenko, Irene; Deguara, Simeon; Di Natale, Antonio; Gatt, Mark; Golet, Walter; Karakulak, Saadet; Kimoto, Ai; Macias, David; Saber, Samar; Santos, Miguel Neves; Zarrad, Rafik

    2015-01-01

    The compiled data for this study represents the first Atlantic and Mediterranean-wide effort to pool all available biometric data for Atlantic bluefin tuna (Thunnus thynnus) with the collaboration of many countries and scientific groups. Biometric relationships were based on an extensive sampling (over 140,000 fish sampled), covering most of the fishing areas for this species in the North Atlantic Ocean and Mediterranean Sea. Sensitivity analyses were carried out to evaluate the representativeness of sampling and explore the most adequate procedure to fit the weight-length relationship (WLR). The selected model for the WLRs by stock included standardized data series (common measurement types) weighted by the inverse variability. There was little difference between annual stock-specific round weight-straight fork length relationships, with an overall difference of 6% in weight. The predicted weight by month was estimated as an additional component in the exponent of the weight-length function. The analyses of monthly variations of fish condition by stock, maturity state and geographic area reflect annual cycles of spawning and feeding behavior. We update and improve upon the biometric relationships for bluefin currently used by the International Commission for the Conservation of Atlantic Tunas, by incorporating substantially larger datasets than ever previously compiled, providing complete documentation of sources and employing robust statistical fitting. WLRs and other conversion factors estimated in this study differ from the ones used in previous bluefin stock assessments. PMID:26505476

  17. Atlantic Bluefin Tuna (Thunnus thynnus) Biometrics and Condition.

    PubMed

    Rodriguez-Marin, Enrique; Ortiz, Mauricio; Ortiz de Urbina, José María; Quelle, Pablo; Walter, John; Abid, Noureddine; Addis, Piero; Alot, Enrique; Andrushchenko, Irene; Deguara, Simeon; Di Natale, Antonio; Gatt, Mark; Golet, Walter; Karakulak, Saadet; Kimoto, Ai; Macias, David; Saber, Samar; Santos, Miguel Neves; Zarrad, Rafik

    2015-01-01

    The compiled data for this study represents the first Atlantic and Mediterranean-wide effort to pool all available biometric data for Atlantic bluefin tuna (Thunnus thynnus) with the collaboration of many countries and scientific groups. Biometric relationships were based on an extensive sampling (over 140,000 fish sampled), covering most of the fishing areas for this species in the North Atlantic Ocean and Mediterranean Sea. Sensitivity analyses were carried out to evaluate the representativeness of sampling and explore the most adequate procedure to fit the weight-length relationship (WLR). The selected model for the WLRs by stock included standardized data series (common measurement types) weighted by the inverse variability. There was little difference between annual stock-specific round weight-straight fork length relationships, with an overall difference of 6% in weight. The predicted weight by month was estimated as an additional component in the exponent of the weight-length function. The analyses of monthly variations of fish condition by stock, maturity state and geographic area reflect annual cycles of spawning and feeding behavior. We update and improve upon the biometric relationships for bluefin currently used by the International Commission for the Conservation of Atlantic Tunas, by incorporating substantially larger datasets than ever previously compiled, providing complete documentation of sources and employing robust statistical fitting. WLRs and other conversion factors estimated in this study differ from the ones used in previous bluefin stock assessments.

  18. Temperature sensitivity of cardiac function in pelagic fishes with different vertical mobilities: yellowfin tuna (Thunnus albacares), bigeye tuna (Thunnus obesus), mahimahi (Coryphaena hippurus), and swordfish (Xiphias gladius).

    PubMed

    Galli, Gina L J; Shiels, Holly A; Brill, Richard W

    2009-01-01

    We measured the temperature sensitivity, adrenergic sensitivity, and dependence on sarcoplasmic reticulum (SR) Ca(2+) of ventricular muscle from pelagic fishes with different vertical mobility patterns: bigeye tuna (Thunnus obesus), yellowfin tuna (Thunnus albacares), and mahimahi (Coryphaena hippurus) and a single specimen from swordfish (Xiphias gladius). Ventricular muscle from the bigeye tuna and mahimahi exhibited a biphasic response to an acute decrease in temperature (from 26 degrees to 7 degrees C); twitch force and kinetic parameters initially increased and then declined. The magnitude of this response was larger in the bigeye tuna than in the mahimahi. Under steady state conditions at 26 degrees C, inhibition of SR Ca(2+) release and reuptake with ryanodine and thapsigargin decreased twitch force and kinetic parameters, respectively, in the bigeye tuna only. However, the initial inotropy associated with decreasing temperature was abolished by SR inhibition in both the bigeye tuna and the mahimahi. Application of adrenaline completely reversed the effects of ryanodine and thapsigargin, but this effect was diminished at cold temperatures. In the yellowfin tuna, temperature and SR inhibition had minor effects on twitch force and kinetics, while adrenaline significantly increased these parameters. Limited data suggest that swordfish ventricular muscle responds to acute temperature reduction, SR inhibition, and adrenergic stimulation in a manner similar to that of bigeye tuna ventricular muscle. In aggregate, our results show that the temperature sensitivity, SR dependence, and adrenergic sensitivity of pelagic fish hearts are species specific and that these differences reflect species-specific vertical mobility patterns.

  19. Mercury Concentrations in Tuna (Thunnus albacares and Thunnus obesus) from the Brazilian Equatorial Atlantic Ocean.

    PubMed

    Lacerda, L D; Goyanna, F; Bezerra, M F; Silva, G B

    2017-02-01

    Average total Hg concentrations measured in muscle of two species of tuna (Thunnus obesus and T. albacares) captured in the Brazilian Equatorial Atlantic Ocean varied from 95 to 1748 ng.g(-1) wet weight in T. obesus and 48 to 500 ng.g(-1) wet weight in T. albacares. Higher concentrations in T. obesus are probably related to foraging on deep water carnivorous fish. Smaller individuals of both species showed the lowest concentrations, but a significant positive relationship between fish weight and length and Hg concentrations was found for T. obesus, but not for T. albacares. Largest individuals (>30 kg) of T. obesus showed Hg concentrations ≥1000 ng.g(-1), surpassing the legal limits for human consumption, although the average concentration for this species was much lower (545 ng.g(-1)). Concentrations in T. albacares from the Brazilian Equatorial were lower than those found in the African and in the North Atlantic. No comparison could be made for T. obesus due to few studies for this species in the Atlantic Ocean.

  20. Discrimination of Juvenile Yellowfin (Thunnus albacares) and Bigeye (T. obesus) Tunas using Mitochondrial DNA Control Region and Liver Morphology

    PubMed Central

    Pedrosa-Gerasmio, Ivane R.; Babaran, Ricardo P.; Santos, Mudjekeewis D.

    2012-01-01

    Yellowfin tuna, Thunnus albacares (Bonnaterre, 1788) and bigeye tuna, Thunnus obesus (Lowe, 1839) are two of the most economically important tuna species in the world. However, identification of their juveniles, especially at sizes less than 40 cm, is very difficult, often leading to misidentification and miscalculation of their catch estimates. Here, we applied the mitochondrial DNA control region D-loop, a recently validated genetic marker used for identifying tuna species (Genus Thunnus), to discriminate juvenile tunas caught by purse seine and ringnet sets around fish aggregating devices (FADs) off the Southern Iloilo Peninsula in Central Philippines. We checked individual identifications using the Neighbor-Joining Method and compared results with morphometric analyses and the liver phenotype. We tested 48 specimens ranging from 13 to 31 cm fork length. Morpho-meristic analyses suggested that 12 specimens (25%) were bigeye tuna and 36 specimens (75%) were yellowfin tuna. In contrast, the genetic and liver analyses both showed that 5 specimens (10%) were bigeye tuna and 43 (90%) yellowfin tuna. This suggests that misidentification can occur even with highly stringent morpho-meristic characters and that the mtDNA control region and liver phenotype are excellent markers to discriminate juveniles of yellowfin and bigeye tunas. PMID:22536417

  1. Molecular Identification of Atlantic Bluefin Tuna (Thunnus thynnus, Scombridae) Larvae and Development of a DNA Character-Based Identification Key for Mediterranean Scombrids

    PubMed Central

    Puncher, Gregory Neils; Arrizabalaga, Haritz; Alemany, Francisco; Cariani, Alessia; Oray, Isik K.; Karakulak, F. Saadet; Basilone, Gualtiero; Cuttitta, Angela; Mazzola, Salvatore; Tinti, Fausto

    2015-01-01

    The Atlantic bluefin tuna, Thunnus thynnus, is a commercially important species that has been severely over-exploited in the recent past. Although the eastern Atlantic and Mediterranean stock is now showing signs of recovery, its current status remains very uncertain and as a consequence their recovery is dependent upon severe management informed by rigorous scientific research. Monitoring of early life history stages can inform decision makers about the health of the species based upon recruitment and survival rates. Misidentification of fish larvae and eggs can lead to inaccurate estimates of stock biomass and productivity which can trigger demands for increased quotas and unsound management conclusions. Herein we used a molecular approach employing mitochondrial and nuclear genes (CO1 and ITS1, respectively) to identify larvae (n = 188) collected from three spawning areas in the Mediterranean Sea by different institutions working with a regional fisheries management organization. Several techniques were used to analyze the genetic sequences (sequence alignments using search algorithms, neighbour joining trees, and a genetic character-based identification key) and an extensive comparison of the results is presented. During this process various inaccuracies in related publications and online databases were uncovered. Our results reveal important differences in the accuracy of the taxonomic identifications carried out by different ichthyoplanktologists following morphology-based methods. While less than half of larvae provided were bluefin tuna, other dominant taxa were bullet tuna (Auxis rochei), albacore (Thunnus alalunga) and little tunny (Euthynnus alletteratus). We advocate an expansion of expertise for a new generation of morphology-based taxonomists, increased dialogue between morphology-based and molecular taxonomists and increased scrutiny of public sequence databases. PMID:26147931

  2. Molecular Identification of Atlantic Bluefin Tuna (Thunnus thynnus, Scombridae) Larvae and Development of a DNA Character-Based Identification Key for Mediterranean Scombrids.

    PubMed

    Puncher, Gregory Neils; Arrizabalaga, Haritz; Alemany, Francisco; Cariani, Alessia; Oray, Isik K; Karakulak, F Saadet; Basilone, Gualtiero; Cuttitta, Angela; Mazzola, Salvatore; Tinti, Fausto

    2015-01-01

    The Atlantic bluefin tuna, Thunnus thynnus, is a commercially important species that has been severely over-exploited in the recent past. Although the eastern Atlantic and Mediterranean stock is now showing signs of recovery, its current status remains very uncertain and as a consequence their recovery is dependent upon severe management informed by rigorous scientific research. Monitoring of early life history stages can inform decision makers about the health of the species based upon recruitment and survival rates. Misidentification of fish larvae and eggs can lead to inaccurate estimates of stock biomass and productivity which can trigger demands for increased quotas and unsound management conclusions. Herein we used a molecular approach employing mitochondrial and nuclear genes (CO1 and ITS1, respectively) to identify larvae (n = 188) collected from three spawning areas in the Mediterranean Sea by different institutions working with a regional fisheries management organization. Several techniques were used to analyze the genetic sequences (sequence alignments using search algorithms, neighbour joining trees, and a genetic character-based identification key) and an extensive comparison of the results is presented. During this process various inaccuracies in related publications and online databases were uncovered. Our results reveal important differences in the accuracy of the taxonomic identifications carried out by different ichthyoplanktologists following morphology-based methods. While less than half of larvae provided were bluefin tuna, other dominant taxa were bullet tuna (Auxis rochei), albacore (Thunnus alalunga) and little tunny (Euthynnus alletteratus). We advocate an expansion of expertise for a new generation of morphology-based taxonomists, increased dialogue between morphology-based and molecular taxonomists and increased scrutiny of public sequence databases.

  3. A Validated Methodology for Genetic Identification of Tuna Species (Genus Thunnus)

    PubMed Central

    Viñas, Jordi; Tudela, Sergi

    2009-01-01

    Background Tuna species of the genus Thunnus, such as the bluefin tunas, are some of the most important and yet most endangered trade fish in the world. Identification of these species in traded forms, however, may be difficult depending on the presentation of the products, which may hamper conservation efforts on trade control. In this paper, we validated a genetic methodology that can fully distinguish between the eight Thunnus species from any kind of processed tissue. Methodology After testing several genetic markers, a complete discrimination of the eight tuna species was achieved using Forensically Informative Nucleotide Sequencing based primarily on the sequence variability of the hypervariable genetic marker mitochondrial DNA control region (mtDNA CR), followed, in some specific cases, by a second validation by a nuclear marker rDNA first internal transcribed spacer (ITS1). This methodology was able to distinguish all tuna species, including those belonging to the subgenus Neothunnus that are very closely related, and in consequence can not be differentiated with other genetic markers of lower variability. This methodology also took into consideration the presence of introgression that has been reported in past studies between T. thynnus, T. orientalis and T. alalunga. Finally, we applied the methodology to cross-check the species identity of 26 processed tuna samples. Conclusions Using the combination of two genetic markers, one mitochondrial and another nuclear, allows a full discrimination between all eight tuna species. Unexpectedly, the genetic marker traditionally used for DNA barcoding, cytochrome oxidase 1, could not differentiate all species, thus its use as a genetic marker for tuna species identification is questioned. PMID:19898615

  4. Spatial variation in fatty acid trophic markers in albacore tuna from the southwestern Pacific Ocean-A potential 'tropicalization' signal

    NASA Astrophysics Data System (ADS)

    Parrish, Christopher C.; Pethybridge, Heidi; Young, Jock W.; Nichols, Peter D.

    2015-03-01

    Signature fatty acids were used to explore trophic variations in albacore and skipjack tuna sampled from the southwestern Pacific Ocean. There were clear spatial differences in fatty acid profiles between albacore sampled in the Coral (tropical zone centered at ~20°S) and Tasman (temperate zone centered at ~42°S) Seas; however, few differences were observed in fatty acid profiles of albacore sampled off Tasmania and New Zealand. Fatty acid signatures of the Tasman Sea samples reflected a food web based more on diatoms and included: 20:5ω3 (EPA), 18:1ω7, 22:1ω11, 18:2ω6, 18:4ω3, 18:3ω3, and 20:4ω3. In contrast, albacore from the Coral Sea had a distinct fatty acid signature which included 20:4ω6, 22:5ω6, 17:0, 22:4ω6, 24:0, and 17:1. Multivariate analyses revealed the importance of 22:6ω3 (DHA) in Coral Sea-caught albacore which also had a DHA/EPA ratio more than twice that in all other groups suggesting a greater dinoflagellate contribution and/or a higher trophic position. Fatty acid markers indicative of krill consumption were significantly higher in temperate-caught albacore although skipjack were closest in fatty acid composition to krill. These results were likely due to differences at the base of the food web in these two seas suggesting that signature fatty acids can be used as indicators of ecosystem change: in this case the gradual 'tropicalization' of the eastern seaboard of Australia through the southward extension of the East Australian Current. Our findings also indicate comparatively lower concentrations of healthful ω3 long-chain polyunsaturated fatty acids, in particular the content of DHA and EPA, in the tropical samples. This suggests that tropicalization could adversely affect the dietary intake of albacore and other marine predators in the region. Such changes are readily detectable by fatty acid analysis.

  5. Total mercury in canned yellowfin tuna Thunnus albacares marketed in northwest Mexico.

    PubMed

    Ruelas-Inzunza, Jorge; Patiño-Mejía, Carlos; Soto-Jiménez, Martín; Barba-Quintero, Guillermo; Spanopoulos-Hernández, Milton

    2011-12-01

    Mercury (Hg) was determined in Thunnus albacares canned in oil (from 7 to 10 samples per brand) and water (from 5 to 10 samples per brand) of five leading brands in Mexico in 2008. Potential health risk was estimated on the basis of Hg concentration and rate (1.43 kg year(-1)per capita) of tuna consumption in Mexico. Highest Hg concentrations were 0.51 ± 0.26 and 0.40 ± 0.24 μ gg(-1) dry weight in water and oil, respectively. Averaged Hg concentrations in tuna canned in water in the current study were comparable to values in Katsuwonus pelamis from Alabama; regarding the oil presentation, Hg levels were lower than in canned tuna collected in Mexico and comparable to values in canned tuna (species not identified) from Turkey. Hazard quotients were 0.0166 and 0.012 in water and oil, respectively. For the analyzed brands and considering tuna consumption in Mexican population, reference dose for this element was not exceeded; therefore, no human health risk is likely to occur. More work is necessary in relation to exposure to Hg from other sources, rates of consumption in strata of population with elevated fish consumption, size of canned tuna and on the role of Se against Hg toxicity.

  6. Do captive conditions favor shedding of parasites in the reared Atlantic bluefin tuna (Thunnus thynnus)?

    PubMed

    Mladineo, I; Segvić, T; Petrić, M

    2011-01-01

    Tuna (Thunnus spp.) has been characterized by long distance migrations, highly predatory behavior and longevity, all of which in turn, enable infections with a wide spectrum of different parasitic groups, reflecting in a remarkable diversity of tuna parasite communities. Since 2003, we have been monitoring parasite communities of Atlantic bluefin tuna (Thunnus thynnus) that are caught from the wild and transferred into cages during spring-summer months, as well as assemblages in fish that exit rearing cycle during the winter harvest period after 1.5 years. Interestingly in reared tuna, parasitic populations exhibit a significant decreasing trend at the end of the rearing cycle, rarely observed in other intensive productions that represent a suitable environment for the emergence, establishment and transmission of pathogens. In order to assess epizootiological behavior of tuna parasites assemblages at the beginning (B group) and at the end (A group) of 1.5 year rearing cycle, we examined data on parasite prevalence and abundance over 4 years. The aim was to evaluate parasite diversity indices and emerging differences between newly caught and harvested fish, as well as community compositions and their nestedness in respect to the event in the rearing cycle (capture or harvest time). In order to be able to predict classification of tuna in two categories (newly caught or heavily infected and harvested or less infected fish), based on empirical didymozoids abundances and year of sampling, we built a decision tree model. Results suggest that specificities of parasite assemblages and their dynamics in tuna before and after farming have no similar precedents in aquaculture. A trend of parasitic pauperization repeating in each rearing cycle over four-years time, in once diverse and species rich parasite communities is observed, however, structures of both B and A group rearing assemblages remain nested, with the same species being core parasites (Didymosulcus katsuwonicola

  7. Seasonal Movements, Aggregations and Diving Behavior of Atlantic Bluefin Tuna (Thunnus thynnus) Revealed with Archival Tags

    PubMed Central

    Walli, Andreas; Teo, Steven L. H.; Boustany, Andre; Farwell, Charles J.; Williams, Tom; Dewar, Heidi; Prince, Eric; Block, Barbara A.

    2009-01-01

    Electronic tags were used to examine the seasonal movements, aggregations and diving behaviors of Atlantic bluefin tuna (Thunnus thynnus) to better understand their migration ecology and oceanic habitat utilization. Implantable archival tags (n = 561) were deployed in bluefin tuna from 1996 to 2005 and 106 tags were recovered. Movement paths of the fish were reconstructed using light level and sea-surface-temperature-based geolocation estimates. To quantify habitat utilization we employed a weighted kernel estimation technique that removed the biases of deployment location and track length. Throughout the North Atlantic, high residence times (167±33 days) were identified in four spatially confined regions on a seasonal scale. Within each region, bluefin tuna experienced distinct temperature regimes and displayed different diving behaviors. The mean diving depths within the high-use areas were significantly shallower and the dive frequency and the variance in internal temperature significantly higher than during transit movements between the high-use areas. Residence time in the more northern latitude high-use areas was significantly correlated with levels of primary productivity. The regions of aggregation are associated with areas of abundant prey and potentially represent critical foraging habitats that have seasonally abundant prey. Throughout the North Atlantic mean diving depth was significantly correlated with the depth of the thermocline, and dive behavior changed in relation to the stratification of the water column. In this study, with numerous multi-year tracks, there appear to be repeatable patterns of clear aggregation areas that potentially are changing with environmental conditions. The high concentrations of bluefin tuna in predictable locations indicate that Atlantic bluefin tuna are vulnerable to concentrated fishing efforts in the regions of foraging aggregations. PMID:19582150

  8. Spatiotemporal variability in bigeye tuna ( Thunnus obesus) dive behavior in the central North Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Howell, Evan A.; Hawn, Donald R.; Polovina, Jeffrey J.

    2010-07-01

    Data from 29 pop-up archival transmission (PAT) tags deployed on commercial-size bigeye tuna ( Thunnus obesus) in the central North Pacific Ocean from 4°N to 32°N were analyzed to describe variability in their dive behavior across space and time. During the day, bigeye tuna generally spent time in the 0-50 m and 300-400 m depth ranges, with spatial and temporal variability in the deep mode. At night, bigeye tuna generally inhabited the 0-100 m depth range. Three daily dive types were defined based on the percentage of time tuna spent in specific depth layers during the day. These three types were defined as shallow, intermediate, and deep and represented 24.4%, 18.8%, and 56.8% of the total number of days in the study, respectively. More shallow and intermediate dive-type behavior was found in the first half of the year, and in latitudes from 14°N to 16°N and north of 28°N. A greater amount of deep-dive behavior was found in the regions south of 10°N and between 18°N and 28°N during the third and fourth quarters of the year. Dive-type behavior also varied with oceanographic conditions, with more shallow and intermediate behavior found in colder surface waters. Intermediate and deep-dive types were pooled to reflect the depths where bigeye tuna may have potential interactions with fishing gear. A Generalized Additive Model was used to quantify the effects of time, space, and sea surface temperature on this pooled dive type. Results from the model showed that while latitude and quarter of the year were important parameters, sea surface temperature had the most significant effect on the pooled intermediate and deep-dive behavior. Model predictions indicated that the largest percentage of potential interaction would occur in the fourth quarter in the region from 18°N-20°N, which corresponds to the time and place of the highest bigeye tuna catch rates by the Hawaii-based long-line fishery. These results suggest that a model framework using these three

  9. Transectional heat transfer in thermoregulating bigeye tuna (Thunnus obesus) - a 2D heat flux model.

    PubMed

    Boye, Jess; Musyl, Michael; Brill, Richard; Malte, Hans

    2009-11-01

    We developed a 2D heat flux model to elucidate routes and rates of heat transfer within bigeye tuna Thunnus obesus Lowe 1839 in both steady-state and time-dependent settings. In modeling the former situation, we adjusted the efficiencies of heat conservation in the red and the white muscle so as to make the output of the model agree as closely as possible with observed cross-sectional isotherms. In modeling the latter situation, we applied the heat exchanger efficiencies from the steady-state model to predict the distribution of temperature and heat fluxes in bigeye tuna during their extensive daily vertical excursions. The simulations yielded a close match to the data recorded in free-swimming fish and strongly point to the importance of the heat-producing and heat-conserving properties of the white muscle. The best correspondence between model output and observed data was obtained when the countercurrent heat exchangers in the blood flow pathways to the red and white muscle retained 99% and 96% (respectively) of the heat produced in these tissues. Our model confirms that the ability of bigeye tuna to maintain elevated muscle temperatures during their extensive daily vertical movements depends on their ability to rapidly modulate heating and cooling rates. This study shows that the differential cooling and heating rates could be fully accounted for by a mechanism where blood flow to the swimming muscles is either exclusively through the heat exchangers or completely shunted around them, depending on the ambient temperature relative to the body temperature. Our results therefore strongly suggest that such a mechanism is involved in the extensive physiological thermoregulatory abilities of endothermic bigeye tuna.

  10. Muscular system in the pacific bluefin tuna Thunnus orientalis (Teleostei: Scombridae).

    PubMed

    Nakae, Masanori; Sasaki, Kunio; Shinohara, Gento; Okada, Tokihiko; Matsuura, Keiichi

    2014-02-01

    The muscular system in the Pacific bluefin tuna Thunnus orientalis is studied in detail. For the first time, a complete description of the muscular anatomy of a thunnid is provided here. Eighty-two elements including subdivisions of components of the muscular system are identified. This is less than found in a basal perciform and two other investigated scombrid species, owing mainly to the absence or fusion of pectoral, pelvic and caudal fin muscles. The absence of elements of the basal perciform pattern was most prominent in the caudal fin, which includes only the flexor dorsalis, flexor ventralis, hypochordal longitudinalis, and interradialis. In the caudal fin, the medial fan-shaped ray was identified as the first dorsal ray, judging from myological and neuroanatomical characters. The highly developed gill filament muscles in Thunnus orientalis and sheet-like rectus communis control gill ventilation. Long body muscle tendons reduce the metabolic energy needed during rapid and continuous swimming. These characters are interpreted as adaptations in the context of the oceanic life style of the species.

  11. Mercury in Pacific bluefin tuna (Thunnus orientalis):bioaccumulation and trans-Pacific Ocean migration

    USGS Publications Warehouse

    Colman, John A.; Nogueira, Jacob I.; Pancorbo, Oscar C.; Batdorf, Carol A.; Block, Barbara A.

    2015-01-01

    Pacific bluefin tuna (Thunnus orientalis) have the largest home range of any tuna species and are well known for the capacity to make transoceanic migrations. We report the measurement of mercury (Hg) concentrations in wild Pacific bluefin tuna (PBFT), the first reported with known size-of-fish and capture location. The results indicate juvenile PBFT that are recently arrived in the California Current from the western Pacific Ocean have significantly higher Hg concentrations in white muscle (0.51 ug/g wet mass, wm) than PBFT of longer California Current residency (0.41 ug/g wm). These new arrivals are also higher in Hg concentration than PBFT in farm pens (0.43 ug/g wm) that were captured on arrival in the California Current and raised in pens on locally derived feed. Analysis by direct Hg analyzer and attention to Hg by tissue type and location on the fish allowed precise comparisons of mercury among wild and captive fish populations. Analysis of migration and nearshore residency, determined through extensive archival tagging, bioaccumulation models, trophic investigations, and potential coastal sources of methylmercury, indicates Hg bioaccumulation is likely greater for PBFT juvenile habitats in the western Pacific Ocean (East China Sea, Yellow Sea) than in the eastern Pacific Ocean (California Current). Differential bioaccumulation may be a trophic effect or reflect methylmercury availability, with potential sources for coastal China (large hypoxic continental shelf receiving discharge of three large rivers, and island-arc volcanism) different from those for coastal Baja California (small continental shelf, no large rivers, spreading-center volcanism).

  12. Electronic Tagging of Atlantic Bluefin Tuna (Thunnus thynnus, L.) Reveals Habitat Use and Behaviors in the Mediterranean Sea

    PubMed Central

    Cermeño, Pablo; Quílez-Badia, Gemma; Ospina-Alvarez, Andrés; Sainz-Trápaga, Susana; Boustany, Andre M.; Seitz, Andy C.; Tudela, Sergi; Block, Barbara A.

    2015-01-01

    We analyzed the movements of Atlantic tuna (Thunnus thynnus L.) in the Mediterranean Sea using data from 2 archival tags and 37 pop-up satellite archival tags (PAT). Bluefin tuna ranging in size from 12 to 248 kg were tagged on board recreational boats in the western Mediterranean and the Adriatic Sea between May and September during two different periods (2000 to 2001 and 2008 to 2012). Although tuna migrations between the Mediterranean Sea and the Atlantic Ocean have been well reported, our results indicate that part of the bluefin tuna population remains in the Mediterranean basin for much of the year, revealing a more complex population structure. In this study we demonstrate links between the western Mediterranean, the Adriatic and the Gulf of Sidra (Libya) using over 4336 recorded days of location and behavior data from tagged bluefin tuna with a maximum track length of 394 days. We described the oceanographic preferences and horizontal behaviors during the spawning season for 4 adult bluefin tuna. We also analyzed the time series data that reveals the vertical behavior of one pop-up satellite tag recovered, which was attached to a 43.9 kg tuna. This fish displayed a unique diving pattern within 16 days of the spawning season, suggesting a use of the thermocline as a thermoregulatory mechanism compatible with spawning. The results obtained hereby confirm that the Mediterranean is clearly an important habitat for this species, not only as spawning ground, but also as an overwintering foraging ground. PMID:25671316

  13. The potential impact of ocean acidification upon eggs and larvae of yellowfin tuna (Thunnus albacares)

    NASA Astrophysics Data System (ADS)

    Bromhead, Don; Scholey, Vernon; Nicol, Simon; Margulies, Daniel; Wexler, Jeanne; Stein, Maria; Hoyle, Simon; Lennert-Cody, Cleridy; Williamson, Jane; Havenhand, Jonathan; Ilyina, Tatiana; Lehodey, Patrick

    2015-03-01

    Anthropogenic carbon dioxide (CO2) emissions are resulting in increasing absorption of CO2 by the earth's oceans, which has led to a decline in ocean pH, a process known as ocean acidification (OA). Evidence suggests that OA may have the potential to affect the distribution and population dynamics of many marine organisms. Early life history processes (e.g. fertilization) and stages (eggs, larvae, juveniles) may be relatively more vulnerable to potential OA impacts, with implications for recruitment in marine populations. The potential impact of OA upon tuna populations has not been investigated, although tuna are key components of pelagic ecosystems and, in the Pacific Ocean, form the basis of one of the largest and most valuable fisheries in the world. This paper reviews current knowledge of potential OA impacts on fish and presents results from a pilot study investigating how OA may affect eggs and larvae of yellowfin tuna, Thunnus albacares. Two separate trials were conducted to test the impact of pCO2 on yellowfin egg stage duration, larval growth and survival. The pCO2 levels tested ranged from present day (~400 μatm) to levels predicted to occur in some areas of the spawning habitat within the next 100 years (<2500 μatm) to 300 years (~<5000 μatm) to much more extreme levels (~10,000 μatm). In trial 1, there was evidence for significantly reduced larval survival (at mean pCO2 levels≥4730 μatm) and growth (at mean pCO2 levels≥2108 μatm), while egg hatch time was increased at extreme pCO2 levels≥10,000 μatm (*intermediate levels were not tested). In trial 2, egg hatch times were increased at mean pCO2 levels≥1573 μatm, but growth was only impacted at higher pCO2 (≥8800 μatm) and there was no relationship with survival. Unstable ambient conditions during trial 2 are likely to have contributed to the difference in results between trials. Despite the technical challenges with these experiments, there is a need for future empirical work which

  14. Incidence of three Kudoa spp., K. neothunni, K. hexapunctata, and K. thunni (Myxosporea: Multivalvulida), in Thunnus tunas distributed in the western Pacific Ocean.

    PubMed

    Kasai, Akihiro; Tsuduki, Hideaki; Jimenez, Lea Angsinco; Li, Ying-Chun; Tanaka, Shuhei; Sato, Hiroshi

    2017-04-01

    A variety of tunas of the genus Thunnus are consumed daily in Japan as sliced raw fish (sashimi and sushi). The consumption of fresh sliced raw fish, i.e., unfrozen or uncooked, can sometimes cause food poisoning that is manifested by transient diarrhea and vomiting for a single day. One of the causes of this type of food poisoning has been identified as live Kudoa septempunctata (Myxosporea: Multivalvulida) in the olive flounder (Paralichthys olivaceus). Furthermore, raw slices of fresh tunas are highly suspected to be a possible causative fish of similar food poisoning in Japan. In the present study, we conducted a survey of kudoid infections in tunas (the yellowfin tuna Thunnus albacares, the Pacific bluefin tuna Thunnus orientalis, and the longtail tuna Thunnus tonggol) fished in the western Pacific Ocean off Japan and several East Asian countries and characterized morphologically and genetically the kudoid myxospores in pseudocysts or cysts dispersed in the trunk muscles. Pseudocysts of solely Kudoa hexapunctata were identified in the Pacific bluefin tuna (four isolates), whereas in the yellowfin tuna (21 isolates) pseudocysts of Kudoa neothunni and K. hexapunctata were detected at a ratio of 15:6, respectively, in addition to cyst-forming Kudoa thunni in five yellowfin tunas. In the trunk muscles of six longtail tunas examined, pseudocysts of K. neothunni (all six fish) and K. hexapunctata (two fish) were densely dispersed. The myxospores of K. neothunni found in these longtail tunas had seven shell valves and polar capsules (SV/PC) instead of the more common six SV/PC arranged symmetrically. Nucleotide sequences of the 18S and 28S ribosomal RNA gene (rDNA), some with the internal transcribed spacer regions as well, of K. hexapunctata and K. neothunni from the three Thunnus spp., including the seven-SV/PC morphotype, were very similar to previously characterized nucleotide sequences of each species, whereas the 18S and 28S rDNA of four isolates of K. thunni

  15. Carbon Monoxide Residues in Vacuum-Packed Yellowfin Tuna Loins (Thunnus Albacares)

    PubMed Central

    Mascolo, Celestina; Palma, Giuseppe; Smaldone, Giorgio; Girasole, Mariagrazia; Anastasio, Aniello

    2015-01-01

    The use of carbon monoxide (CO) in fresh fish has generated considerable debate. Carbon monoxide is used to treat fresh fish in order to retain its fresh red appearance for a longer period. It reacts with the oxy-myoglobin to form a fairly stable cherry red carboxy-myoglobin complex that may mask spoilage, because the CO-complex can be stable beyond the microbiological shelf life of the meat. The presence of CO in tuna fish (Thunnus Albacares) has been investigated by means of optical spectroscopy. Formation of the CO adduct can be easily detected by the combined analysis of electronic absorption spectra in their normal and second derivative modes, monitoring the intense Soret band at 420 nm. Samples were judged as CO treated when their levels were higher than 200 ng/g. Only two positive samples out of 29 analyzed were detected. The high level of uncertainty (0.30) of the method requires the use of more specific and sensitive methods for confirmatory analysis. PMID:27800404

  16. Near resonance acoustic scattering from organized schools of juvenile Atlantic bluefin tuna (Thunnus thynnus).

    PubMed

    Weber, Thomas C; Lutcavage, Molly E; Schroth-Miller, Madeline L

    2013-06-01

    Schools of Atlantic bluefin tuna (Thunnus thynnus) can exhibit highly organized spatial structure within the school. This structure was quantified for dome shaped schools using both aerial imagery collected from a commercial spotter plane and 400 kHz multibeam echo sounder data collected on a fishing vessel in 2009 in Cape Cod Bay, MA. Observations from one school, containing an estimated 263 fish within an approximately ellipsoidal volume of 1900 m(3), were used to seed an acoustic model that estimated the school target strength at frequencies between 10 and 2000 Hz. The fish's swimbladder resonance was estimated to occur at approximately 50 Hz. The acoustic model examined single and multiple scattering solutions and also a completely incoherent summation of scattering responses from the fish. Three levels of structure within the school were examined, starting with fish locations that were constrained by the school boundaries but placed according to a Poisson process, then incorporating a constraint on the distance to the nearest neighbor, and finally adding a constraint on the bearing to the nearest neighbor. Results suggest that both multiple scattering and spatial organization within the school should be considered when estimating the target strength of schools similar to the ones considered here.

  17. Responses of the red blood cells from two high-energy-demand teleosts, yellowfin tuna (Thunnus albacares) and skipjack tuna (Katsuwonus pelamis), to catecholamines.

    PubMed

    Lowe, T E; Brill, R W; Cousins, K L

    1998-08-01

    In fishes, catecholamines increase red blood cell intracellular pH through stimulation of a sodium/proton (Na+/H+) antiporter. This response can counteract potential reductions in blood O2 carrying capacity (due to Bohr and Root effects) when plasma pH and intracellular pH decrease during hypoxia, hypercapnia, or following exhaustive exercise. Tuna physiology and behavior dictate exceptionally high rates of O2 delivery to the tissues often under adverse conditions, but especially during recovery from exhaustive exercise when plasma pH may be reduced by as much as 0.4 pH units. We hypothesize that blood O2 transport during periods of metabolic acidosis could be especially critical in tunas and the response of rbc to catecholamines elevated to an extreme. We therefore investigated the in vitro response of red blood cells from yellowfin tuna (Thunnus albacares) and skipjack tuna (Katsuwonus pelamis) to catecholamines. Tuna red blood cells had a typical response to catecholamines, indicated by a rapid decrease in plasma pH. Amiloride reduced the response, whereas 4,4'diisothiocyanatostilbene-2,2'-disulphonic acid enhanced both the decrease in plasma pH and the increase in intracellular pH. Changes in plasma [Na+], [Cl-], and [K+] were consistent with the hypothesis that tuna red blood cells have a Na+/H+ antiporter similar to that described for other teleost red blood cells. Red blood cells from both tuna species were more responsive to noradrenaline than adrenaline. At identical catecholamine concentrations, the decrease in plasma pH was greater in skipjack tuna blood, the more active of the two tuna species. Based on changes in plasma pH, the response of red blood cells to catecholamines from both tuna species was less than that of rainbow trout (Oncorhynchus mykiss) red blood cells, but greater than that of cod (Gadus morhua) red blood cells. Noradrenaline had no measurable influence on the O2 affinity of skipjack tuna blood and only slightly increased the O2

  18. Changes in the Distribution of Atlantic Bluefin Tuna (Thunnus thynnus) in the Gulf of Maine 1979-2005

    PubMed Central

    Golet, Walter J.; Galuardi, Benjamin; Cooper, Andrew B.; Lutcavage, Molly E.

    2013-01-01

    The Gulf of Maine, NW Atlantic Ocean, is a productive, seasonal foraging ground for Atlantic bluefin tuna (Thunnus thynnus), but commercial landings of adult size classes were up to 40% below the allocated total allowable catch between 2004 to 2008 for the rod and reel, harpoon, and purse seine categories in the Gulf of Maine. Reduction in Atlantic bluefin tuna catches in the Gulf of Maine could represent a decline in spawning stock biomass, but given wide-ranging, complex migration patterns, and high energetic requirements, an alternative hypothesis is that their dispersal patterns shifted to regions with higher prey abundance or profitability, reducing availability to U.S. fishing fleets. This study fit generalized linear models to Atlantic bluefin tuna landings data collected from fishermen’s logbooks (1979-2005) as well as the distances between bluefin tuna schools and Atlantic herring (Clupeaharengus), a primary prey species, to test alternative hypotheses for observed shifts in Atlantic bluefin tuna availability in the Gulf of Maine. For the bluefin model, landings varied by day of year, latitude and longitude. The effect of latitude differed by day of year and the effect of longitude differed by year. The distances between Atlantic bluefin tuna schools and Atlantic herring schools were significantly smaller (p<0.05) than would be expected from a randomly distributed population. A time series of average bluefin tuna school positions was positively correlated with the average number of herring captured per tow on Georges Bank in spring and autumn surveys respectively (p<0.01, r2=0.24, p<0.01, r2=0.42). Fishermen’s logbooks contributed novel spatial and temporal information towards testing these hypotheses for the bluefin tuna fishery. PMID:24069420

  19. Changes in the distribution of atlantic bluefin tuna (Thunnus thynnus) in the Gulf of Maine 1979-2005.

    PubMed

    Golet, Walter J; Galuardi, Benjamin; Cooper, Andrew B; Lutcavage, Molly E

    2013-01-01

    The Gulf of Maine, NW Atlantic Ocean, is a productive, seasonal foraging ground for Atlantic bluefin tuna (Thunnus thynnus), but commercial landings of adult size classes were up to 40% below the allocated total allowable catch between 2004 to 2008 for the rod and reel, harpoon, and purse seine categories in the Gulf of Maine. Reduction in Atlantic bluefin tuna catches in the Gulf of Maine could represent a decline in spawning stock biomass, but given wide-ranging, complex migration patterns, and high energetic requirements, an alternative hypothesis is that their dispersal patterns shifted to regions with higher prey abundance or profitability, reducing availability to U.S. fishing fleets. This study fit generalized linear models to Atlantic bluefin tuna landings data collected from fishermen's logbooks (1979-2005) as well as the distances between bluefin tuna schools and Atlantic herring (Clupeaharengus), a primary prey species, to test alternative hypotheses for observed shifts in Atlantic bluefin tuna availability in the Gulf of Maine. For the bluefin model, landings varied by day of year, latitude and longitude. The effect of latitude differed by day of year and the effect of longitude differed by year. The distances between Atlantic bluefin tuna schools and Atlantic herring schools were significantly smaller (p<0.05) than would be expected from a randomly distributed population. A time series of average bluefin tuna school positions was positively correlated with the average number of herring captured per tow on Georges Bank in spring and autumn surveys respectively (p<0.01, r(2)=0.24, p<0.01, r(2)=0.42). Fishermen's logbooks contributed novel spatial and temporal information towards testing these hypotheses for the bluefin tuna fishery.

  20. Stereological comparison of oocyte recruitment and batch fecundity estimates from paraffin and resin sections using spawning albacore (Thunnus alalunga) ovaries as a case study

    NASA Astrophysics Data System (ADS)

    Saber, Sámar; Macías, David; Ortiz de Urbina, Josetxu; Kjesbu, Olav Sigurd

    2015-01-01

    Traditional histological protocols in marine fish reproductive laboratories using paraffin as the embedding medium are now increasingly being replaced with protocols using resin instead. These procedures entail different degrees of tissue shrinkage complicating direct comparisons of measurement results across laboratories or articles. In this work we selected ovaries of spawning Mediterranean albacore (Thunnus alalunga) as the subject of our study to address the issue of structural changes, by contrasting values on oocyte recruitment and final batch fecundity given from the same tissue samples in both paraffin and resin. A modern stereological method, the oocyte packing density (OPD) theory, was used supported by initial studies on ovarian tissue sampling and measurement design. Examples of differences in the volume fraction of oocyte stages, free space and connective tissue were found between the embedding media. Mean oocyte diameters were smaller in paraffin than in resin with differences ranging between 0.5% in primary growth and 24.3% in hydration (HYD) stage oocytes. Fresh oocyte measurements showed that oocytes shrank as a consequence of the embedding process, reaching the maximal degree of shrinkage for oocytes in the HYD stage (45.8% in paraffin and 26.5% in resin). In order to assess the effect of oocyte shrinkage on the OPD result, and thereby on relative batch fecundity (Fr), oocyte diameters corrected and uncorrected for shrinkage, were used for estimations. Statistical significant differences were found (P < 0.05) between these two approaches in both embedding media. The average Fr was numerically smaller in paraffin compared to resin (86 ± 61 vs. 106 ± 54 oocytes per gram of body mass (mean ± SD)). For both embedding media statistical significant differences (P < 0.05) were seen between Fr results based on either oocytes in the germinal vesicle migration stage or HYD stage. As a valuable adjunct, the present use of the OPD theory made it possible

  1. [Spatial-temporal distribution of bigeye tuna Thunnus obesus in the tropical Atlantic Ocean based on Argo data].

    PubMed

    Yang, Sheng-long; Jin, Shao-fei; Hua, Cheng-jun; Dai, Yang

    2015-02-01

    In order to analyze the correlation between spatial-temporal distribution of the bigeye tuna ( Thunnus obesus) and subsurface factors, the study explored the isothermal distribution of subsurface temperatures in the bigeye tuna fishing grounds in the tropical Atlantic Ocean, and built up the spatial overlay chart of the isothermal lines of 9, 12, 13 and 15 °C and monthly CPUE (catch per unit effort) from bigeye tuna long-lines. The results showed that the bigeye tuna mainly distributed in the water layer (150-450 m) below the lower boundary depth of thermocline. At the isothermal line of 12 °C, the bigeye tuna mainly lived in the water layer of 190-260 m, while few individuals were found at water depth more than 400 m. As to the 13 °C isothermal line, high CPUE often appeared at water depth less than 250 m, mainly between 150-230 m, while no CPUE appeared at water depth more than 300 m. The optimum range of subsurface factors calculated by frequency analysis and empirical cumulative distribution function (ECDF) exhibited that the optimum depth range of 12 °C isothermal depth was 190-260 m and the 13 °C isothermal depth was 160-240 m, while the optimum depth difference range of 12 °C isothermal depth was -10 to 100 m and the 13 °C isothermal depth was -40 to 60 m. The study explored the optimum range of subsurface factors (water temperature and depth) that drive horizontal and vertical distribution of bigeye tuna. The preliminary result would help to discover the central fishing ground, instruct fishing depth, and provide theoretical and practical references for the longline production and resource management of bigeye tuna in the Atlantic Ocean.

  2. Spawning Dynamics and Size Related Trends in Reproductive Parameters of Southern Bluefin Tuna, Thunnus maccoyii

    PubMed Central

    Farley, Jessica. H.; Davis, Tim L. O.; Bravington, Mark V.; Andamari, Retno; Davies, Campbell R.

    2015-01-01

    Knowledge of spawning behaviour and fecundity of fish is important for estimating the reproductive potential of a stock and for constructing appropriate statistical models for assessing sustainable catch levels. Estimates of length-based reproductive parameters are particularly important for determining potential annual fecundity as a function of fish size, but they are often difficult to estimate reliably. Here we provide new information on the reproductive dynamics of southern bluefin tuna (SBT) Thunnus maccoyii through the analysis of fish size and ovary histology collected on the spawning ground in 1993–1995 and 1999–2002. These are used to refine previous parameter estimates of spawning dynamics and investigate size related trends in these parameters. Our results suggest that the small SBT tend to arrive on the spawning ground slightly later and depart earlier in the spawning season relative to large fish. All females were mature and the majority were classed as spawning capable (actively spawning or non-spawning) with a very small proportion classed as regressing. The fraction of females spawning per day decreased with fish size, but once females start a spawning episode, they spawned daily irrespective of size. Mean batch fecundity was estimated directly at 6.5 million oocytes. Analysis of ovary histology and ovary weight data indicated that relative batch fecundity, and the duration of spawning and non-spawning episodes, increased with fish size. These reproductive parameter estimates could be used with estimates of residency time on the spawning ground as a function of fish size (if known) and demographic data for the spawning population to provide a time series of relative annual fecundity for SBT. PMID:25993276

  3. Schooling behaviour of juvenile Pacific bluefin tuna Thunnus orientalis depends on their vision development.

    PubMed

    Torisawa, S; Fukuda, H; Suzuki, K; Takagi, T

    2011-11-01

    The effects of vision development and light intensity on schooling behaviour during growth in juvenile Pacific bluefin tuna Thunnus orientalis were investigated using both behavioural and histological approaches. The schooling behaviour of three age groups [25, 40 and 55 days post hatching (dph)] of juvenile T. orinetalis were examined under various light intensities. Subsequently, schooling variables, such as the nearest neighbour distance (D(NN) ) and the separation swimming index (I(SS) ), were also measured under different light intensities. Furthermore, retinal indices of light adaptation in juvenile fish at each experimental light intensity and visual acuities in six stages (25-55 dph) of juveniles were examined histologically. During growth, the light intensity thresholds of I(SS) decreased from 5 to 0·05 lx, and D(NN) under light conditions (>300 lx) also decreased from 9·2 times the standard length (L(S) ) to 1·2 times L(S) . The thresholds of light intensities for the light adaptation of retinas in juveniles (25-55 dph) similarly decreased from 5 to 0·05 lx with growth. In addition, the visual acuities of juveniles developed from 0·04 to 0·17 with decreasing D(NN) . These data clearly indicate that the characteristics of schooling behaviour strongly correspond to the degree of vision development. Juvenile T. orinetalis also appear to be more dependent on cone rather than rod cells under low light intensity conditions, resulting in a relatively high light intensity threshold for schooling. These results suggest that juveniles can adapt to darker conditions during growth by developing improved visual capabilities.

  4. Habitat and behaviour of yellowfin tuna Thunnus albacares in the Gulf of Mexico determined using pop-up satellite archival tags.

    PubMed

    Weng, K C; Stokesbury, M J W; Boustany, A M; Seitz, A C; Teo, S L H; Miller, S K; Block, B A

    2009-05-01

    This study presents the first data on movement, habitat use and behaviour for yellowfin tuna Thunnus albacares in the Atlantic Basin. Six individuals were tracked in the Gulf of Mexico using pop-up satellite archival tags. Records up to 80 days in length were obtained, providing information on depth and temperature preferences as well as horizontal movements. Thunnus albacares in the Gulf of Mexico showed a strong preference for the mixed layer and thermocline, consistent with findings for this species in other ocean basins. Fish showed a diel pattern in depth distribution, remaining in surface and mixed layer waters at night and diving to deeper waters during the day. The vertical extent of T. albacares habitat appeared to be temperature limited, with fish generally avoiding waters that were >6 degrees C cooler than surface waters. The vertical and thermal habitat usage of T. albacares differs from that of bigeye Thunnus obesus and bluefin Thunnus thynnus, Thunnus orientalis and Thunnus maccoyii tunas. These results are consistent with the results of earlier studies conducted on T. albacares in other oceans.

  5. Atlantic bluefin tuna Thunnus thynnus feeding ecology in the northern Gulf of Mexico: a preliminary description of diet from the western Atlantic spawning grounds.

    PubMed

    Butler, C M; Logan, J M; Provaznik, J M; Hoffmayer, E R; Staudinger, M D; Quattro, J M; Roberts, M A; Ingram, G W; Pollack, A G; Lutcavage, M E

    2015-01-01

    A combination of stomach contents, nitrogen stable-isotope and tissue C:N values are presented to demonstrate feeding activity of Atlantic bluefin tuna Thunnus thynnus on the Gulf of Mexico (GOMEX) spawning grounds. Diets include teleosts, cephalopods, crustaceans and a pelagic tunicate (Pyrosoma atlanticum). Results reveal the need to classify the GOMEX as a T. thynnus feeding ground.

  6. HCB, p,p'-DDE and PCB ontogenetic transfer and magnification in bluefin tuna (Thunnus thynnus) from the Mediterranean Sea.

    PubMed

    Corsolini, Simonetta; Sarà, Gianluca; Borghesi, Nicoletta; Focardi, Silvano

    2007-06-15

    The bluefin tuna, Thunnus thynnus (Linnaeus 1758), is biologically and economically important in the Atlantic--Mediterranean ecosystems. Bluefin tuna feed on diverse food items depending on their age, thus they occupy different trophic levels during their lifespan. Hexachlorobenzene (HCB), p,p'-DDE and polychlorinated biphenyls (PCBs) are well-known persistent organic pollutants (POPs) in the Mediterranean basin. The relationship between stable isotopes of nitrogen (N) and the POP residue levels in tissues has recently increased knowledge on the link between the trophic levels and the contaminant accumulation. Trophic levels were estimated by using 15N/14N ratio (delta15N) and HCB, p,p'-DDE, and forty-three PCBs were quantified in bluefin tuna from the southern Tyrrhenian Sea. Results showed that changes in PCB and p,p'-DDE concentrations were a function of size and trophic level, while no correlations were observed for HCB. Apart from HCB and PCB nos. 101, 207, 95, 158, and 60 + 56, which did not show any significant increase per trophic level, the other PCBs and the p,p'-DDE increased significantly. The ontogenetic magnification factor of PCBs was 6.6 +/- 0.5, which was significantly (12 times) higher (p < 0.05) than the values found for p,p'-DDE (1.4) and HCB (1.4).

  7. Spawning behaviour and post-spawning migration patterns of atlantic bluefin tuna (Thunnus thynnus) ascertained from satellite archival tags.

    PubMed

    Aranda, Guillermo; Abascal, Francisco Javier; Varela, José Luis; Medina, Antonio

    2013-01-01

    Spawning behaviour of Atlantic bluefin tuna (Thunnus thynnus) was investigated using electronic satellite tags deployed in the western Mediterranean spawning ground, around the Balearic Islands (years 2009-2011). All the fish were tagged underwater and released within schools. In general, the fish tagged in the same year/school displayed common migratory trends. Following extended residency around the Balearic Islands, most tagged tuna crossed the Strait of Gibraltar heading for the North Atlantic. Discrepancies between the migratory tracks reconstructed from this and previous electronic tagging studies suggest that the bluefin tuna Mediterranean population may comprise distinct units exhibiting differing migratory behaviours. The diving behaviour varied between oceanic regions throughout the migratory pathways, the shallowest distribution taking place in the spawning ground and the deepest at the Strait of Gibraltar. A unique diving pattern was found on the majority of nights while the fish stayed at the spawning ground; it consisted of frequent and brief oscillatory movements up and down through the mixed layer, resulting in thermal profiles characterized by oscillations about the thermocline. Such a pattern is believed to reflect recent courtship and spawning activity. Reproductive parameters inferred from the analysis of vertical profiles are consistent with those estimated in previous studies based on biological samples.

  8. Spawning Behaviour and Post-Spawning Migration Patterns of Atlantic Bluefin Tuna (Thunnus thynnus) Ascertained from Satellite Archival Tags

    PubMed Central

    Aranda, Guillermo; Abascal, Francisco Javier; Varela, José Luis; Medina, Antonio

    2013-01-01

    Spawning behaviour of Atlantic bluefin tuna (Thunnus thynnus) was investigated using electronic satellite tags deployed in the western Mediterranean spawning ground, around the Balearic Islands (years 2009-2011). All the fish were tagged underwater and released within schools. In general, the fish tagged in the same year/school displayed common migratory trends. Following extended residency around the Balearic Islands, most tagged tuna crossed the Strait of Gibraltar heading for the North Atlantic. Discrepancies between the migratory tracks reconstructed from this and previous electronic tagging studies suggest that the bluefin tuna Mediterranean population may comprise distinct units exhibiting differing migratory behaviours. The diving behaviour varied between oceanic regions throughout the migratory pathways, the shallowest distribution taking place in the spawning ground and the deepest at the Strait of Gibraltar. A unique diving pattern was found on the majority of nights while the fish stayed at the spawning ground; it consisted of frequent and brief oscillatory movements up and down through the mixed layer, resulting in thermal profiles characterized by oscillations about the thermocline. Such a pattern is believed to reflect recent courtship and spawning activity. Reproductive parameters inferred from the analysis of vertical profiles are consistent with those estimated in previous studies based on biological samples. PMID:24098502

  9. Increased liver apoptosis and tumor necrosis factor expression in Atlantic bluefin tuna (Thunnus thynnus) reared in the northern Adriatic Sea.

    PubMed

    Corriero, Aldo; Zupa, Rosa; Pousis, Chrysovalentinos; Santamaria, Nicoletta; Bello, Giambattista; Jirillo, Emilio; Carrassi, Michele; De Giorgi, Carla; Passantino, Letizia

    2013-06-15

    The Atlantic bluefin tuna Thunnus thynnus (ABFT) is intensely fished in the Mediterranean Sea to supply a prosperous capture-based mariculture industry. Liver apoptotic structures and tumor necrosis factor (TNF) gene expression were determined in: wild ABFT caught in the eastern Atlantic; juvenile ABFT reared in the central Adriatic Sea; juvenile ABFT reared in the northern Adriatic Sea; adult ABFT reared in the western Mediterranean. The highest density of liver apoptotic structures was found in the juveniles from the northern Adriatic. Two partial TNF cDNAs (TNF1 and TNF2) were cloned and sequenced. TNF1 gene expression was higher in juveniles than in adults. The highest expression of TNF2 was found in the juveniles from the northern Adriatic. These findings might be related to the juvenile exposure to environmental pollutants.

  10. Benefits and risks associated with consumption of raw, cooked, and canned tuna (Thunnus spp.) based on the bioaccessibility of selenium and methylmercury.

    PubMed

    Afonso, C; Costa, S; Cardoso, C; Oliveira, R; Lourenço, H M; Viula, A; Batista, I; Coelho, I; Nunes, M L

    2015-11-01

    The Se, Hg, and methylmercury (MeHg) levels in raw, cooked (boiled and grilled), and canned tuna (Thunnus spp.) were determined before and after an in vitro digestion, thereby enabling the calculation of the respective bioaccessibility percentages. A risk-benefit evaluation of raw and canned tuna on the basis of the Se and MeHg data was performed. Selenium bioaccessibility was high in tuna, though slightly lower in canned than in raw products. Mercury levels were high in raw and cooked tuna. Hg bioaccessibility percentages were low (39-48%) in the cooked tuna and even lower (<20%) in canned tuna. For the bioaccessible fraction, all molar Se:MeHg ratios were higher than one (between 10 and 74). A probabilistic assessment of MeHg risk vs Se benefit showed that while a weekly meal of canned tuna presents very low risk, raw, boiled, and grilled tuna consumption should not exceed a monthly meal, at least, for pregnant and nursing women.

  11. Through the stomach of a predator: Regional patterns of forage in the diet of albacore tuna in the California Current System and metrics needed for ecosystem-based management

    NASA Astrophysics Data System (ADS)

    Glaser, Sarah M.; Waechter, Katrina E.; Bransome, Nicole C.

    2015-06-01

    Foraging habits of predators can reveal patterns in prey ecology and guide ecosystem-based management by informing species interactions. This study describes the diet habits of albacore tuna in three regions (north, central, south) of the California Current System (CCS) and estimates the total predation mortality imposed on twenty prey taxa. The northern CCS was defined by predation on decapods, euphausiids, anchovy and hake. The central CCS was defined by predation on squid, hake and Pacific saury. The southern CCS was defined by predation on anchovy. We estimate North Pacific albacore consumed each year, on average, 54,000 mt of decapods and euphausiids, 43,000 mt of cephalopods, 84,000 mt of juvenile hake, 1600 mt of myctophids, 21,000 mt of juvenile sardine, 10,000 mt of juvenile rockfishes, almost 43,000 mt of Pacific saury, and over 107,000 mt of juvenile anchovy. While variability in predation certainly exists, this and prior studies show that diet habits of albacore are fairly stable through time. The northern CCS appears to be a more significant source of energy for albacore. When designing ecosystem-based approaches to the management of CCS-based fisheries, we recommend that the forage contribution of saury, hake and anchovy to the albacore population be considered.

  12. Mercury accumulation in Yellowfin tuna (Thunnus albacares) with regards to muscle type, muscle position and fish size.

    PubMed

    Bosch, Adina C; O'Neill, Bernadette; Sigge, Gunnar O; Kerwath, Sven E; Hoffman, Louwrens C

    2016-01-01

    The concentrations and relationships between individual mercury species and total mercury were investigated in different muscle parts and sizes of Yellowfin tuna (Thunnus albacares). Fourteen Yellowfin tuna caught in the South Atlantic off the coast of South Africa had an average total Hg (tHg) concentration of 0.77 mg/kg wet weight. No differences were detected (p > 0.05) in tHg, MethylHg (MeHg) or inorganic Hg (iHg) accumulation among the four white muscle portions across the carcass, but both tHg and iHg were found in higher concentrations (p < 0.001) in dark muscle than white muscle. Positive linear correlations with fish weight were found for both tHg (r = 0.79, p < 0.001) and MeHg (r = 0.75, p < 0.001) concentrations. A prediction model was formulated to calculate toxic MeHg concentrations from measured tHg concentrations and fish weight (cMeHg = 0.073 + 1.365 · tHg-0.008 · w). As sampling sites and subsampling methods could affect toxicity measurements, we provide recommendations for sampling guidelines.

  13. Microsatellite and mitochondrial DNA analyses of Atlantic bluefin tuna (Thunnus thynnus thynnus) population structure in the Mediterranean Sea.

    PubMed

    Carlsson, Jens; McDowell, Jan R; Díaz-Jaimes, Píndaro; Carlsson, Jeanette E L; Boles, Sandra B; Gold, John R; Graves, John E

    2004-11-01

    Genetic variation was surveyed at nine microsatellite loci and the mitochondrial control region (868 bp) to test for the presence of genetic stock structure in young-of-the-year Atlantic bluefin tuna (Thunnus thynnus thynnus) from the Mediterranean Sea. Bluefin tuna were sampled over a period of 5 years from the Balearic and Tyrrhenian seas in the western basin of the Mediterranean Sea, and from the southern Ionian Sea in the eastern basin of the Mediterranean Sea. Analyses of multilocus microsatellite genotypes and mitochondrial control region sequences revealed no significant heterogeneity among collections taken from the same location in different years; however, significant spatial genetic heterogeneity was observed across all samples for both microsatellite markers and mitochondrial control region sequences (FST=0.0023, P=0.038 and PhiST=0.0233, P=0.000, respectively). Significant genetic differentiation between the Tyrrhenian and Ionian collections was found for both microsatellite and mitochondrial markers (FST=0.0087, P=0.015 and PhiST=0.0367, P=0.030, respectively). These results suggest the possibility of a genetically discrete population in the eastern basin of the Mediterranean Sea.

  14. Heavy metals in yellowfin tuna (Thunnus albacares) and common dolphinfish (Coryphaena hippurus) landed on the Ecuadorian coast.

    PubMed

    Araújo, Cristiano V M; Cedeño-Macias, Luis A

    2016-01-15

    Heavy metals are contaminants of great environmental concern due to their multiple origins (natural and anthropogenic), the ability to accumulate in organs and tissues, and the deleterious effects they can cause in organisms. Studies on the accumulation of metals in seafood, such as fish, have increased in importance due to the risk for human health when consuming fish contaminated by metals. The present work was aimed at verifying the concentrations of cadmium (Cd), mercury (Hg) and lead (Pb) in the muscular tissue and liver of yellowfin tuna (Thunnus albacares) and common dolphinfish (Coryphaena hippurus) from the Eastern Pacific Ocean landed in Manta city, Ecuador. Samples were analyzed by inductively coupled plasma mass spectroscopy (ICP-MS). Around half of the muscle samples of both species presented levels of Cd and Hg above the limits considered safe for human consumption established by the European Union. For Pb,most of the muscle samples were considered acceptable for consumption. Results indicate that both species should be consumed with some caution. Considering the tolerable weekly intake recommended for adults by the World Health Organization, results indicate that Hg is the main metal that limits the consumption of yellowfin tuna and common dolphinfish, with a recommended maximum ingestion, respectively, of 191 and 178 g per week for an adult.c

  15. Microarray gene expression profiles from mature gonad tissues of Atlantic bluefin tuna, Thunnus thynnus in the Gulf of Mexico

    PubMed Central

    2012-01-01

    Background Bluefin tunas are highly prized pelagic fish species representing a significant economic resource to fisheries throughout the world. Atlantic bluefin tuna (Thunnus thynnus) populations have significantly declined due to overexploitation. As a consequence of their value and population decline, T. thynnus has been the focus of considerable research effort concerning many aspects of their life history. However, in-depth understanding of T. thynnus reproductive biology is still lacking. Knowledge of reproductive physiology is a very important tool for determining effective fisheries and aquaculture management. Transcriptome techniques are proving powerful and provide novel insights into physiological processes. Construction of a microarray from T. thynnus ESTs sourced from reproductive tissues has provided an ideal platform to study the reproductive physiology of bluefin tunas. The aim of this investigation was to compare transcription profiles from the ovaries and testes of mature T. thynnus to establish sex specific variations underlying their reproductive physiology. Results Male and females T. thynnus gonad tissues were collected from the wild and histologically staged. Sub-samples of sexually mature tissues were also measured for their mRNA differential expression among the sexes using the custom microarray design BFT 4X44K. A total of 7068 ESTs were assessed for differential expression of which 1273 ESTs were significantly different (p<0.05) with >2 fold change in expression according to sex. Differential expression for 13 of these ESTs was validated with quantitative PCR. These include genes involved in egg envelope formation, hydration, and lipid transport/accumulation more highly expressed in ovaries compared with testis, while genes involved in meiosis, sperm motility and lipid metabolism were more highly expressed in testis compared with ovaries. Conclusions This investigation has furthered our knowledge of bluefin tunas reproductive biology by

  16. Metazoan gill parasites of the Atlantic bluefin tuna Thunnus thynnus (Linnaeus) (Osteichthyes: Scombridae) from the Mediterranean and their possible use as biological tags.

    PubMed

    Culurgioni, Jacopo; Mele, Salvatore; Merella, Paolo; Addis, Piero; Figus, Vincenza; Cau, Angelo; Karakulak, Firdes Saadet; Garippa, Giovanni

    2014-04-01

    The gills of 63 specimens of the Atlantic bluefin tuna Thunnus thynnus (Linnaeus) (Osteichthyes: Scombridae) from three localities of the Mediterranean (Sardinian, Tyrrhenian and Levantine Seas) were examined for metazoan parasites. The parasite fauna of T. thynnus from the Sea of Sardinia included 11 species: five didymozoid trematodes, three capsalid and one hexostomid monogeneans, and one caligid and one pseudocycnid copepods. Four didymozoids were found in fish from the Levantine Sea and only one didymozoid was recorded in fish from the Tyrrhenian Sea. Dividing the hosts into four size-groups (small, medium-sized, large and extra large), the pairwise comparison of prevalence and mean abundance of the new and literary data) showed differences according to host size. The differences in the composition of the parasitic faunas and in the prevalence of parasites, observed between the small tunas from the Tyrrhenian Sea and the medium-sized tunas from the Adriatic Sea, Levantine Sea and the North-East (NE) Atlantic Ocean, indicated that these groups form discrete units. The parasite fauna of the large tunas from the Sea of Sardinia is the richest among the bluefin tuna populations of the Mediterranean and the NE Atlantic, due to the presence of species not found elsewhere in bluefin tunas, such as Caligus coryphaenae Steenstrup et Lütken, 1861, Capsala magronum (Ishii, 1936) and C. paucispinosa (Mamaev, 1968). This fact and the prevalence of some parasites of this group (lower than those of medium-sized fish from the NE Atlantic and higher than the small and medium-sized tunas from the Mediterranean) suggest that the large-sized tuna group in the western Mediterranean is formed by Mediterranean resident tunas (poorly infected), and by tunas migrating from the Atlantic Ocean (heavily infected).

  17. 75 FR 67948 - Proposed Information Collection; Comment Request; U.S.-Canada Albacore Treaty Reporting System

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-04

    ... Information Collection; Comment Request; U.S.-Canada Albacore Treaty Reporting System AGENCY: National Oceanic....)-Canada Albacore Tuna Treaty of 1981 (Treaty). Owners of vessels that fish from U.S. West Coast ports for... Canada each year indicating vessels eligible to fish for albacore tuna in waters under the...

  18. Discovery of a spawning ground reveals diverse migration strategies in Atlantic bluefin tuna (Thunnus thynnus)

    PubMed Central

    Richardson, David E.; Marancik, Katrin E.; Guyon, Jeffrey R.; Lutcavage, Molly E.; Galuardi, Benjamin; Lam, Chi Hin; Walsh, Harvey J.; Wildes, Sharon; Yates, Douglas A.; Hare, Jonathan A.

    2016-01-01

    Atlantic bluefin tuna are a symbol of both the conflict between preservationist and utilitarian views of top ocean predators, and the struggle to reach international consensus on the management of migratory species. Currently, Atlantic bluefin tuna are managed as an early-maturing eastern stock, which spawns in the Mediterranean Sea, and a late-maturing western stock, which spawns in the Gulf of Mexico. However, electronic tagging studies show that many bluefin tuna, assumed to be of a mature size, do not visit either spawning ground during the spawning season. Whether these fish are spawning in an alternate location, skip-spawning, or not spawning until an older age affects how vulnerable this species is to anthropogenic stressors including exploitation. We use larval collections to demonstrate a bluefin tuna spawning ground in the Slope Sea, between the Gulf Stream and northeast United States continental shelf. We contend that western Atlantic bluefin tuna have a differential spawning migration, with larger individuals spawning in the Gulf of Mexico, and smaller individuals spawning in the Slope Sea. The current life history model, which assumes only Gulf of Mexico spawning, overestimates age at maturity for the western stock. Furthermore, individual tuna occupy both the Slope Sea and Mediterranean Sea in separate years, contrary to the prevailing view that individuals exhibit complete spawning-site fidelity. Overall, this complexity of spawning migrations questions whether there is complete independence in the dynamics of eastern and western Atlantic bluefin tuna and leads to lower estimates of the vulnerability of this species to exploitation and other anthropogenic stressors. PMID:26951668

  19. Discovery of a spawning ground reveals diverse migration strategies in Atlantic bluefin tuna (Thunnus thynnus).

    PubMed

    Richardson, David E; Marancik, Katrin E; Guyon, Jeffrey R; Lutcavage, Molly E; Galuardi, Benjamin; Lam, Chi Hin; Walsh, Harvey J; Wildes, Sharon; Yates, Douglas A; Hare, Jonathan A

    2016-03-22

    Atlantic bluefin tuna are a symbol of both the conflict between preservationist and utilitarian views of top ocean predators, and the struggle to reach international consensus on the management of migratory species. Currently, Atlantic bluefin tuna are managed as an early-maturing eastern stock, which spawns in the Mediterranean Sea, and a late-maturing western stock, which spawns in the Gulf of Mexico. However, electronic tagging studies show that many bluefin tuna, assumed to be of a mature size, do not visit either spawning ground during the spawning season. Whether these fish are spawning in an alternate location, skip-spawning, or not spawning until an older age affects how vulnerable this species is to anthropogenic stressors including exploitation. We use larval collections to demonstrate a bluefin tuna spawning ground in the Slope Sea, between the Gulf Stream and northeast United States continental shelf. We contend that western Atlantic bluefin tuna have a differential spawning migration, with larger individuals spawning in the Gulf of Mexico, and smaller individuals spawning in the Slope Sea. The current life history model, which assumes only Gulf of Mexico spawning, overestimates age at maturity for the western stock. Furthermore, individual tuna occupy both the Slope Sea and Mediterranean Sea in separate years, contrary to the prevailing view that individuals exhibit complete spawning-site fidelity. Overall, this complexity of spawning migrations questions whether there is complete independence in the dynamics of eastern and western Atlantic bluefin tuna and leads to lower estimates of the vulnerability of this species to exploitation and other anthropogenic stressors.

  20. Lipid metabolism-related gene expression pattern of Atlantic bluefin tuna (Thunnus thynnus L.) larvae fed on live prey.

    PubMed

    Betancor, Mónica B; Ortega, Aurelio; de la Gándara, Fernando; Tocher, Douglas R; Mourente, Gabriel

    2016-11-04

    The present study is the first to evaluate lipid metabolism in first-feeding Atlantic bluefin tuna (ABT; Thunnus thynnus L.) larvae fed different live prey including enriched rotifers Brachionus plicatilis and Acartia sp. copepod nauplii from 2 days after hatch. Understanding the molecular basis of lipid metabolism and regulation in ABT will provide insights to optimize diet formulations for this high-value species new to aquaculture. To this end, we investigated the effect of dietary lipid on whole larvae lipid class and fatty acid compositions and the expression of key genes involved in lipid metabolism in first feeding ABT larvae fed different live prey. Additionally, the expression of lipid metabolism genes in tissues of adult broodstock ABT was evaluated. Growth and survival data indicated that copepods were the best live prey for first feeding ABT and that differences in growth performance and lipid metabolism observed between larvae from different year classes could be a consequence of broodstock nutrition. In addition, expression patterns of lipid metabolic genes observed in ABT larvae in the trials could reflect differences in lipid class and fatty acid compositions of the live prey. The lipid nutritional requirements, including essential fatty acid requirements of larval ABT during the early feeding stages, are unknown, and the present study represents a first step in addressing these highly relevant issues. However, further studies are required to determine nutritional requirements and understand lipid metabolism during development of ABT larvae and to apply the knowledge to the commercial culture of this iconic species.

  1. Potential impacts of climate change on the distribution of longline catches of yellowfin tuna (Thunnus albacares) in the Tasman sea

    NASA Astrophysics Data System (ADS)

    Dell, James T.; Wilcox, Chris; Matear, Richard J.; Chamberlain, Matthew A.; Hobday, Alistair J.

    2015-03-01

    The spatial distribution of living marine resources in the Tasman Sea is expected to shift due to the impacts of global climate change. Understanding the most likely future locations of valuable pelagic species will inform the sustainable harvest and management of species such as yellowfin tuna (YFT; Thunnus albacares). We estimate future upper ocean structure in the Tasman Sea, using both historical data and dynamically downscaled ocean projections for the 2060s, and apply a catch distribution model to estimate possible changes to the YFT catch in the eastern Australia domestic longline fishery. Both approaches project that locations with concentrated YFT catch in the Tasman Sea will shift poleward in response to likely climate change. By the 2060s, the core fishing areas are projected to have shifted both poleward and offshore of existing high catch areas. Shifts in the distribution and hence availability of this species may require future domestic fishing vessels to modify their fishing behaviors, which in turn may require social and economic adjustments.

  2. Determination of cadmium, lead and mercury residual levels in meat of canned light tuna (Katsuwonus pelamis and Thunnus albacares) and fresh little tunny (Euthynnus alletteratus) in Libya

    PubMed Central

    Abolghait, S.K.; Garbaj, A.M.

    2015-01-01

    Surveillance for mercury (Hg), lead (Pb) and cadmium (Cd) contamination in tuna products is crucial for consumer food safety. Hg, Pb and Cd contaminants were monitored in a total of 60 specimens of fresh little tunny (Euthynnus alletteratus) and popular brands of skipjack and yellowfin (Katsuwonus pelamis and Thunnus albacares) canned tuna commercially available in Tripoli, Libya. Direct Mercury Analyzer (DMA-80) was implemented for determination of total Hg level and graphite furnace atomic absorption spectrometry (GFAAS) was employed for determination of Cd and Pb concentrations. The results indicated that Hg had the highest concentration level and Cd had the lowest concentration level either in tested canned tuna or fresh little tunny samples. The average concentration of Hg in fresh little tunny samples was 1.185 ± 0.968 mg kg-1 wet weight (ww) and often exceeded the standard permissible limit. In addition, canned yellowfin tuna had the lowest levels of Cd (0.027 ± 0.026 mg kg-1 ww), Pb (0.075 ± 0.071) and Hg (0.163 ± 0.122 mg kg-1 ww). Results of the current surveillance indicated that canned skipjack and yellowfin tuna sold in Tripoli markets show contaminant levels well under the European thresholds adopted for Cd, Pb and Hg. However, consumption of large quantities of Mediterranean little tunny products significantly increases human exposure to the risk of Hg toxicity. PMID:26623379

  3. Shifting from marine reserves to maritime zoning for conservation of Pacific bigeye tuna (Thunnus obesus)

    PubMed Central

    Sibert, John; Senina, Inna; Lehodey, Patrick; Hampton, John

    2012-01-01

    Over 50% of the total bigeye tuna (BET) landed in the Western Central Pacific Ocean is caught incidentally in the purse seine fishery and sold for canning at prices less than US$2/kg. The remainder is landed in longline fisheries directed at BET and sold as fresh or frozen tuna at prices greater than US$10/kg. The combined fishing mortality by all gears will soon reduce the BET biomass in the Pacific Ocean to less than that capable of producing maximum sustainable yield. Closure of the high-seas enclaves in 2009 was hailed as a conservation measure, but was not scientifically evaluated before implementation and appears to have had no beneficial effect on the BET stock. A spatially explicit age-structured ecosystem model, SEAPODYM, is used to simulate alternative area-based fishery management policies to conserve bigeye tuna in the Western Central Pacific Ocean. Closing the high-seas enclaves to purse seine fishing has negligible effect on the BET biomass. Fishery management policies that control mortality on both juveniles and adults, through prohibition of fish aggregation devices in the purse seine fishery and restrictions on longline fishing in spawning areas, are the most efficient conservation policies. Large-scale benefits from bigeye conservation measures will become apparent only in the 2030s, assuming timely implementation and minimal effects of climate change. PMID:23064639

  4. Shifting from marine reserves to maritime zoning for conservation of Pacific bigeye tuna (Thunnus obesus).

    PubMed

    Sibert, John; Senina, Inna; Lehodey, Patrick; Hampton, John

    2012-10-30

    Over 50% of the total bigeye tuna (BET) landed in the Western Central Pacific Ocean is caught incidentally in the purse seine fishery and sold for canning at prices less than US$2/kg. The remainder is landed in longline fisheries directed at BET and sold as fresh or frozen tuna at prices greater than US$10/kg. The combined fishing mortality by all gears will soon reduce the BET biomass in the Pacific Ocean to less than that capable of producing maximum sustainable yield. Closure of the high-seas enclaves in 2009 was hailed as a conservation measure, but was not scientifically evaluated before implementation and appears to have had no beneficial effect on the BET stock. A spatially explicit age-structured ecosystem model, SEAPODYM, is used to simulate alternative area-based fishery management policies to conserve bigeye tuna in the Western Central Pacific Ocean. Closing the high-seas enclaves to purse seine fishing has negligible effect on the BET biomass. Fishery management policies that control mortality on both juveniles and adults, through prohibition of fish aggregation devices in the purse seine fishery and restrictions on longline fishing in spawning areas, are the most efficient conservation policies. Large-scale benefits from bigeye conservation measures will become apparent only in the 2030s, assuming timely implementation and minimal effects of climate change.

  5. Biomagnification of mercury and its antagonistic interaction with selenium in yellowfin tuna Thunnus albacares in the trophic web of Baja California Sur, Mexico.

    PubMed

    Ordiano-Flores, Alfredo; Rosíles-Martínez, Rene; Galván-Magaña, Felipe

    2012-12-01

    Mercury and selenium concentrations were determined in muscle of 37 yellowfin tuna (Thunnus albacares) captured aboard of Mexican purse-seiners boats off western coast of Baja California Sur, between Punta Eugenia and Cabo Falso, from October to December 2006. Also, its prey (mainly, jumbo squid Dosidicus gigas and pelagic red crab Pleuroncodes planipes) were analyzed from the stomach contents. All the mercury values obtained were lower that mercury content recommended by standard legal limits for seafood adopted by Mexican norms (typically 0.5-1.0μg g(-1)). Mercury concentrations vary between 0.06 and 0.51μg g(-1) in yellowfin tuna, and from 0.01 to 0.20μg g(-1) in its prey, suggesting that mercury can accumulate in prey tissues and that of their predator. Biomagnification factors (BMF) between predator-prey associations were calculated. The BMFs were >1, indicating that mercury biomagnifies along the food web of yellowfin tuna. In all species studied there was a molar excess of selenium over mercury. The rank order of mean selenium/mercury molar ratios was for pufferfish (42.62)> diamond squid (15.09)>yellowfin tuna (10.29)>pelagic red crab (10.05)>panama lightfish (9.54)> jumbo squid (8.91). The selenium health benefit value (Se-HBV) was calculated to have an improved understanding of the health benefits and risk of fish consumption.

  6. Genetic structuring and migration patterns of Atlantic bigeye tuna, Thunnus obesus (Lowe, 1839)

    PubMed Central

    2008-01-01

    Background Large pelagic fishes are generally thought to have little population genetic structuring based on their cosmopolitan distribution, large population sizes and high dispersal capacities. However, gene flow can be influenced by ecological (e.g. homing behaviour) and physical (e.g. present-day ocean currents, past changes in sea temperature and levels) factors. In this regard, Atlantic bigeye tuna shows an interesting genetic structuring pattern with two highly divergent mitochondrial clades (Clades I and II), which are assumed to have been originated during the last Pleistocene glacial maxima. We assess genetic structure patterns of Atlantic bigeye tuna at the nuclear level, and compare them with mitochondrial evidence. Results We examined allele size variation of nine microsatellite loci in 380 individuals from the Gulf of Guinea, Canary, Azores, Canada, Indian Ocean, and Pacific Ocean. To investigate temporal stability of genetic structure, three Atlantic Ocean sites were re-sampled a second year. Hierarchical AMOVA tests, RST pairwise comparisons, isolation by distance (Mantel) tests, Bayesian clustering analyses, and coalescence-based migration rate inferences supported unrestricted gene flow within the Atlantic Ocean at the nuclear level, and therefore interbreeding between individuals belonging to both mitochondrial clades. Moreover, departures from HWE in several loci were inferred for the samples of Guinea, and attributed to a Wahlund effect supporting the role of this region as a spawning and nursery area. Our microsatellite data supported a single worldwide panmictic unit for bigeye tunas. Despite the strong Agulhas Current, immigration rates seem to be higher from the Atlantic Ocean into the Indo-Pacific Ocean, but the actual number of individuals moving per generation is relatively low compared to the large population sizes inhabiting each ocean basin. Conclusion Lack of congruence between mt and nuclear evidences, which is also found in other

  7. Burst Feeding of Pelagia noctiluca ephyrae on Atlantic Bluefin Tuna (Thunnus thynnus) Eggs

    PubMed Central

    Gordoa, Ana; Acuña, José Luis; Farrés, Roser; Bacher, Kathrin

    2013-01-01

    This study investigates the predation of P. noctiluca ephyrae on Atlantic Bluefin tuna (ABFT) eggs under different experimental conditions. The specific factors considered in the experimental design were: a) water mix conditions to explore predation under two-dimensional (2D) and three-dimensional (3D) prey distributions, b) prey density to investigate the ingestion rate capacity, and c) incubation time to inspect gut saturation. The eggs and jellyfish ephyrae were collected during the 2012 ABFT spawning survey off Ibiza (Balearic Isl., Western Mediterranean). The results showed that the proportion of feeding ephyrae increased with size. The mean clearance rate of feeding ephyrae, 4.14 L h-1, was the highest ever recorded for ephyrae. Under calm conditions the eggs floated at the surface (2D spatial arrangement) and the clearance rates, at low prey densities, were at least twice those under mixed conditions (3D spatial arrangement). At high prey density, clearance rate did not differ between mix conditions, probably due to the fast gut saturation, which was reached in c.a. 15 min, as revealed by time series observations of gut contents. The fast saturation of ephyrae and their slow digestion time of approximately 18 h suggest the existence of a diel feeding periodicity. We conclude that in the Western Mediterranean, P. noctiluca ephyrae are capable of predating on ABFT eggs, a highly pulsed and spatially restricted resource that potentially switches from a 3D to a 2D configuration in the absence of wind-generated turbulence. The P. noctiluca and Atlantic Bluefin tuna egg system might represent an example of a general mechanism linking pelagic and neustonic food webs. PMID:24069335

  8. Endogenous level of acetic acid in yellowfin tuna (Thunnus albacares): a pilot study about a possible controversy on its residue nature.

    PubMed

    Chiesa, Luca Maria; Pasquale, Elisa; Panseri, Sara; Britti, Domenico; Malandra, Renato; Villa, Roberto; Arioli, Francesco

    2017-03-01

    A method based on headspace solid-phase microextraction (HS-SPME) followed by GC-MS analysis was developed for the determination of underivatised acetic acid in fresh tuna fish muscle. Parameters such as the fibre selected and the extraction time and temperature were optimised and the linearity, detection limits and precision of the whole analytical procedure were assessed. The method was then applied to determine the acetic acid concentration in fresh yellowfin tuna muscles (Thunnus albacares) in order to evaluate the endogenous level and its variations during the shelf life under different storage conditions. A qualitative comparison was also made with variations in histamine levels to evaluate the possibility of the joint monitoring of acetic acid and histamine to identify fish stored in poor conditions. The caudal area always had a lower content of acetic acid than the ventral area, independent of the storage time and temperature. A difference was found between the 6- and 3-day time points and day 0 at a storage temperature of 8°C and between the 6-day time point and day 0 at a storage temperature of 0°C, independent of the anatomical area of the sampled tissue. The evaluation of acetic acid could represent an important approach in the field of food safety to detect the illicit use of acetic acid as an antibacterial preservative treatment or to eliminate the unpleasant smell of trimethylamine.

  9. Skin lesions on yellowfin tuna Thunnus albacares from Gulf of Mexico outer continental shelf: Morphological, molecular, and histological diagnosis of infection by a capsalid monogenoid.

    PubMed

    Bullard, Stephen A; Womble, Matthew R; Maynard, Margaret K; Orélis-Ribeiro, Raphael; Arias, Cova R

    2015-12-01

    We characterize lesion-associated capsaline infections on yellowfin tuna, Thunnus albacares, in the Gulf of Mexico by comparing our specimens with published descriptions and museum specimens ascribed to Capsala biparasiticum and its synonyms: vouchers of C. biparasiticum from parasitic copepods; the holotype of Capsala neothunni; and vouchers of Capsala abidjani. Those from parasitic copepods differed by having a small, rounded body, large anterior attachment organs, closely spaced dorsomarginal body sclerites, small testes, and a short and wide testicular field. No morphometric feature in the holotype of C. neothunni ranged outside of that reported for the newly-collected specimens, indicating conspecificity of our specimens. The specimens of C. abidjani differed by having a large anterior attachment organ, few and dendritic testes, and a short, wide testicular field. Large subunit ribosomal DNA (28S) sequences grouped our specimens and Capsala sp. as sister taxa and indicated a phylogenetic affinity of Nasicola klawei. The haptoral attachment site comprised a crater-like depression surrounded by a blackish-colored halo of extensively rugose skin, with abundant pockmarked-like, irregularly-shaped oblong or semi-circular epidermal pits surrounding these attachment sites. Histology confirmed extensive folding of epidermis and underlying stratum laxum, likely epidermal hyperplasia, foci of weak cell-to-cell adhesions among apical malpighian cells as well as that between stratum germinativum and stratum laxum, myriad goblet cells in epidermis, rodlet cells in apical layer of epidermis, and lymphocytic infiltrates and melanin in dermis. The present study comprises (i) the first published report of this parasite from yellowfin tuna captured in the Gulf of Mexico-NW Atlantic Ocean Basin, (ii) confirmation of its infection on the skin (rather than on a parasitic copepod), (iii) the first molecular data for this capsaline, and (iv) the first observations of

  10. Characterization of the spawning habitat of Atlantic bluefin tuna and related species in the Balearic Sea (western Mediterranean)

    NASA Astrophysics Data System (ADS)

    Alemany, F.; Quintanilla, L.; Velez-Belchí, P.; García, A.; Cortés, D.; Rodríguez, J. M.; Fernández de Puelles, M. L.; González-Pola, C.; López-Jurado, J. L.

    2010-07-01

    Within the framework of the TUNIBAL project that focused on Atlantic bluefin tuna ( Thunnus thynnus) larval ecology, ichthyoplankton surveys were conducted from 2001 to 2005 off the Balearic archipelago, which is recognized as one of the main spawning areas of the eastern Atlantic stock of this species. In each survey, a regular sampling grid of about 200 stations, 10 nautical miles apart were sampled. CTD casts and oblique Bongo 60 and surface Bongo 90 plankton tows were carried out. The occurrence frequencies of Atlantic bluefin tuna, albacore tuna ( Thunnus alalunga) and bullet tuna ( Auxis rochei) larvae in quantitative Bongo 60 samples were 0.14, 0.29 and 0.49 respectively. Mean larval abundances in these positive samples were relatively high: 31 larvae 10 m -2 for Atlantic bluefin tuna, 17 for albacore tuna and 31 for bullet tuna. All species had patchy distributions since more than 90% of the stations showed larval densities under 10 larvae 100 m -3 (70% showed even less than 2 larvae 100 m -3), whereas in some isolated spots, we recorded abundances as high as 867 (Atlantic bluefin) or 872 (bullet tuna) larvae 10 m -2. These results allowed us to relate larval distribution to mesoscale hydrographic features and to characterize the spawning habitat of these species. Single Quotient Parameter analyses were applied to spatial (depth), physical (temperature, salinity, dissolved oxygen and geostrophic current velocities) and biological (mesozooplankton biomass) variables to determine the environmental preferences of each species for spawning. Results showed that the complex hydrodynamic scenarios around the Balearic Islands, due to the interaction between the inflowing surface Atlantic water masses (AW) and Mediterranean surface waters (MW), play a key role in determining the abundance and distribution of tuna larvae in this area, especially in the case of Atlantic bluefin tuna. Spawning of this species seems to take place mainly in offshore mixed waters, as

  11. Mercury in tunas and blue marlin in the North Pacific Ocean.

    PubMed

    Drevnick, Paul E; Brooks, Barbara A

    2017-03-06

    Models and data from the North Pacific Ocean indicate that mercury concentrations in water and biota are increasing in response to (global or hemispheric) anthropogenic mercury releases. In the present study, we provide an updated record of mercury in yellowfin tuna (Thunnus albacares) caught near Hawaii that confirms an earlier conclusion that mercury concentrations in these fish are increasing at a rate similar to that observed in waters shallower than 1000 m. We also compiled and reanalyzed data from bigeye tuna (Thunnus obesus) and blue marlin (Makaira nigricans) caught near Hawaii in the 1970s and 2000s. Increases in mercury concentrations in bigeye tuna are consistent with the trend found in yellowfin tuna, in both timing and magnitude. The data available for blue marlin do not allow for a fair comparison among years, because mercury concentrations differ between sexes for this species, and sex was identified (or reported) in only 3 of 7 studies. Also, mercury concentrations in blue marlin may be insensitive to modest changes in mercury exposure, because this species appears to have the ability to detoxify mercury. The North Pacific Ocean is a region of both relatively high rates of atmospheric mercury deposition and capture fisheries production. Other data sets that allow temporal comparisons in mercury concentrations, such as pacific cod (Gadus macrocephalus) in Alaskan waters and albacore tuna (Thunnus alalunga) off the US Pacific coast, should be explored further, to aid in understanding human health and ecological risks and to develop additional baseline knowledge for assessing changes in a region expected to respond strongly to reductions in anthropogenic mercury emissions. Environ Toxicol Chem 2016;9999:1-10. © 2017 SETAC.

  12. Characterization of the ribosomal RNA gene of Kudoa neothunni (Myxosporea: Multivalvulida) in tunas (Thunnus spp.) and Kudoa scomberi n. sp. in a chub mackerel (Scomber japonicus).

    PubMed

    Li, Ying-Chun; Sato, Hiroshi; Tanaka, Shuhei; Ohnishi, Takahiro; Kamata, Yoichi; Sugita-Konishi, Yoshiko

    2013-05-01

    Kudoa neothunni is the first described Kudoa species having six shell valves and polar capsules, previously assigned to the genus Hexacapsula Arai and Matsumoto, 1953. Since its genetic analyses remain to be conducted, the present study characterizes the ribosomal RNA gene (rDNA) using two isolates from a yellowfin tuna (Thunnus albacares) with post-harvest myoliquefaction and a northern bluefin tuna (Thunnus thynnus) without tissue degradation. Spores of the two isolates localized in the myofiber of trunk muscles, forming pseudocysts, and showed typical morphology of K. neothunni with six equal-sized shell valves radially arranged in apical view: spores (n = 15) measuring 9.5-11.4 μm in width, 7.3-8.6 μm in suture width, 8.9-10.9 μm in thickness, and 7.3-7.7 μm in length; and polar capsules measuring 3.6-4.1 μm by 1.8-2.3 μm. In lateral view, the spores were pyramidal in shape without apical protrusions. Their 18S and 5.8S rDNA sequences were essentially identical, but variations in the ITS1 (62.4 % similarity across 757-bp length), ITS2 (66.9 % similarity across 599-bp length), and 28S (99.0 % similarity across 2,245-bp length) rDNA regions existed between the two isolates. On phylogenetic trees based on the 18S or 28S rDNA sequence, K. neothunni formed a clade with Kudoa spp. with more than four shell valves and polar capsules, particularly K. grammatorcyni and K. scomberomori. Semiquadrate spores of a kudoid species with four shell valves and polar capsules were detected from minute cysts (0.30-0.75 mm by 0.20-0.40 mm) embedded in the trunk muscle of a chub mackerel (Scomber japonicus) fished in the Sea of Japan. Morphologically, it resembled K. caudata described from a chub mackerel fished in the southeastern Pacific Ocean off Peru; however, it lacked filamentous projections on the shell valves of spores. Additionally, it morphologically resembled K. thunni described from a yellowfin tuna also fished in the Pacific Ocean; spores (n

  13. Effects of on-board and dockside handling on the formation of biogenic amines in mahimahi (Coryphaena hippurus), skipjack tuna (Katsuwonus pelamis), and yellowfin tuna (Thunnus albacares).

    PubMed

    Staruszkiewicz, Walter F; Barnett, James D; Rogers, Patricia L; Benner, Ronald A; Wong, Lynn L; Cook, John

    2004-01-01

    Consumer illnesses by scombroid poisonings have been a continuing problem for many years. The intoxications follow the ingestion of fish such as tuna and mahimahi that have undergone bacterial decomposition, leading to the formation of biogenic amines. Research studies have concluded that histamine is one of the indicators of scombrotoxic fish and that other amines, such as cadaverine, could be involved in the illnesses. Guidance for the handling of fish on board fishing vessels to prevent the production of scombrotoxic fish has been limited by a lack of data addressing changes that occur in fish from the water to delivery at dockside. In this study, the changes in selected biogenic amines were determined in mahimahi and tuna, which were captured and held in seawater at 25 to 35 degrees C for incubation times up to 18 h. The fillets from the treated fish were sectioned by transverse cuts and analyzed for histamine, cadaverine, and putrescine. Results showed that at 26 degrees C, more than 12 h of incubation were required before a histamine concentration of 50 ppm was reached in mahimahi. At 35 degrees C, 50 ppm histamine formed within 9 h. Similar results were found for skipjack and yellowfin tuna. Histamine concentrations exceeded 500 ppm within an additional 3 h of incubation in mahimahi. At both temperatures, an increase in the concentration of cadaverine preceded an increase in histamine levels. Changes in putrescine concentrations in the fish were less pronounced. The study also demonstrated that histidine decarboxylase activity was retained in some frozen samples of fish and could result in further increases in histamine on thawing.

  14. The relationship between fat content and biological parameters of bigeye tuna ( Thunnus obseus) in the Western Central Indian Ocean

    NASA Astrophysics Data System (ADS)

    Song, Liming; Shen, Zhibin; Li, Jie; Li, Dongjing; Li, Yuwei

    2016-10-01

    Comparing fat content with physiological status can throw light on the reproduction and feeding behavior of the fish. The biological data of 586 bigeye tuna were collected from the longline fishery in the waters of Western Central Indian Ocean from November, 2012 to March, 2013. The spatial or temporal distribution of the fat content, and the relationships of fat content with gender, round weight, gonadal maturity and fork length were analyzed. A generalized additive model (GAM) was used to analyze the relationships between fat content and fork length (FL), gonadosomatic index (GSI), condition factor (K), and somatic index (SI). Results showed that: 1) the fat content of bigeye tuna was in the range of 3.1%-27.1% with the average 12.8%; 2) there were no significant geographical differences of average fat content ( P > 0.05) among 1° squares in general; 3) there were no significant differences ( P > 0.05) of the fat content for different genders, months, or gonad maturity stages; 4) there was an extremely significant correlation ( P = 0.000) between fat content and FL and GSI. There was no significant correlation ( P = 0.051) between fat content and K. There was a significant correlation ( P = 0.003) between fat content and SI. The results of this study suggest that the fat content of the matured fish was relatively stable. The survey area was in a spawning region, and the survey period was the spawning season for bigeye tuna.

  15. Evidence of discrete yellowfin tuna (Thunnus albacares) populations demands rethink of management for this globally important resource

    NASA Astrophysics Data System (ADS)

    Grewe, P. M.; Feutry, P.; Hill, P. L.; Gunasekera, R. M.; Schaefer, K. M.; Itano, D. G.; Fuller, D. W.; Foster, S. D.; Davies, C. R.

    2015-11-01

    Tropical tuna fisheries are central to food security and economic development of many regions of the world. Contemporary population assessment and management generally assume these fisheries exploit a single mixed spawning population, within ocean basins. To date population genetics has lacked the required power to conclusively test this assumption. Here we demonstrate heterogeneous population structure among yellowfin tuna sampled at three locations across the Pacific Ocean (western, central, and eastern) via analysis of double digest restriction-site associated DNA using Next Generation Sequencing technology. The differences among locations are such that individuals sampled from one of the three regions examined can be assigned with close to 100% accuracy demonstrating the power of this approach for providing practical markers for fishery independent verification of catch provenance in a way not achieved by previous techniques. Given these results, an extended pan-tropical survey of yellowfin tuna using this approach will not only help combat the largest threat to sustainable fisheries (i.e. illegal, unreported, and unregulated fishing) but will also provide a basis to transform current monitoring, assessment, and management approaches for this globally significant species.

  16. Distribution of persistent organic pollutants (POPS) IN wild Bluefin tuna (Thunnus thynnus) from different FAO capture zones.

    PubMed

    Chiesa, L M; Labella, G F; Panseri, S; Pavlovic, R; Bonacci, S; Arioli, F

    2016-06-01

    Residues of environmental contaminants in food represent a concern in food safety programs. In this study, the distribution of persistent organic pollutants (POPs) were evaluated in 79 tuna samples from FAO areas 51 (Indian Ocean), 71 (Pacific Ocean), 34 (Atlantic Ocean), and 37 (Mediterranean Sea). 6 polychlorinated biphenyls (PCBs), 16 organochlorines (OCs) and 7 polybrominated biphenyl ethers (PBDEs) were selected as representative compounds according to EFSA POPs monitoring guidelines. An analytical method, based on Accelerated Solvent Extraction (ASE), with an "in-line" clean-up step and GC-MS/MS detection, was developed, validated and applied. PCBs were detected in all FAO areas, with a prevalence of 100% for most of them. In the FAO area 37, only, all PBDEs were detected. Only 5 OCs were detected. The results showed that POPs contamination of tuna reflects FAO area contamination; in particular FAO area 37 was the most polluted. Moreover, tuna muscle was an appropriate matrix for monitoring contamination and for obtaining information about food safety.

  17. Case-control study of epidemic mortality and Cardicola forsteri-associated disease in farmed southern bluefin tuna (Thunnus maccoyii) of South Australia.

    PubMed

    Dennis, M M; Landos, M; D'Antignana, T

    2011-07-01

    Cardicola forsteri is a blood fluke that is highly prevalent among cultured southern bluefin tuna (SBT), Thunnus maccoyii, in South Australia. The role of C forsteri in annual SBT mortality outbreaks, which peak 6 to 12 weeks poststocking, is unknown. The objective of this study was to identify lesions unique to cultured SBT that died during a mortality event in 2009 and to determine the significance of C forsteri-associated lesions. Cultured SBT were sampled from 4 pontoons of a single site in Spencer Gulf that experienced a mortality epidemic that spanned 5 to 14 weeks poststocking. Study SBT comprised 7 that died during peak mortality, 27 that did not die, and 10 wild-caught (noncultured) SBT. All cultured SBT had branchitis and myocarditis due to C forsteri, whereas no life stages of C forsteri were histologically identified in any wild-caught SBT. Mortality was associated with the presence of severe branchitis (P<.005), and the odds of severe branchitis were 90 times greater for SBT that died than for SBT that were live caught during peak mortality (95% confidence interval, 5 to 1,684). In SBT that had died, no lesions other than those associated with C forsteri were of sufficient severity or physiologic significance to account for death. Other lesions common among cultured SBT included systemic granulocytic perivascular infiltrate, granulocytic gastric infiltrate, hepatic lipidosis, visceral granulomas, and branchial parasitic infestation. This study shows for the first time that a substantial proportion of poststocking mortality in cultured SBT is strongly associated with severe branchitis caused by C forsteri.

  18. Evaluation of FAD-associated purse seine fishery reduction strategies for bigeye tuna ( Thunnus obesus) in the Indian Ocean

    NASA Astrophysics Data System (ADS)

    Tong, Yuhe; Chen, Xinjun; Xu, Liuxiong; Chen, Yong

    2013-07-01

    In the Indian Ocean, bigeye tuna supports one of the most important fisheries in the world. This fishery mainly consists of two components: longline and purse seine fisheries. Evidence of overfishing and stock depletion of bigeye tuna calls for an evaluation of alternative management strategies. Using an age-structured operating model, parameterized with the results derived in a recent stock assessment, we evaluated the effectiveness of applying constant fishing mortality (CF) and quasi-constant fishing mortality (QCF) strategies to reduce fishing effort of purse seining with fish aggregating devices (FADs) at different rates. Three different levels of productivity accounted for the uncertainty in our understanding of stock productivity. The study shows that the results of CF and QCF are similar. Average SSB and catch during simulation years would be higher if fishing mortality of FAD-associated purse seining was reduced rapidly. The banning or rapid reduction of purse seining with FAD resulted in a mean catch, and catch in the last simulation year, higher than that of the base case in which no change was made to the purse seine fishery. This could be caused by growth overfishing by purse seine fisheries with FADs according to the per-recruit analysis. These differences would be more obvious when stock productivity was low. Transferring efforts of FAD-associated purse seining to longline fisheries is also not feasible. Our study suggests that changes are necessary to improve the performance of the current management strategy.

  19. Empirical models to identify mechanisms driving reductions in tissue mercury concentration during culture of farmed southern bluefin tuna Thunnus maccoyii.

    PubMed

    Balshaw, S; Edwards, J W; Ross, K E; Ellis, D; Padula, D J; Daughtry, B J

    2008-12-01

    Two empirical models are presented to elucidate the mechanisms driving reductions in the mercury concentration of southern bluefin tuna (SBT) during culture. Model 1 predicts temporal fluctuations in mercury concentration in response to growth dilution. Model 2 predicts the combined effects of growth dilution and linear mercury accumulation. Model 2 was found to be the more accurate model. Over a typical farming period of 136 days, growth dilution resulted in a reduction in mean mercury concentration of SBT edible tissues from 0.51 mg/kg down to 0.33 mg/kg. Extended culture beyond 136 days resulted in an increase in mercury concentration due to the combined effects of mercury accumulation and seasonal lipid depletion. Results indicate that under current industry practice, cultured SBT can be consumed twice as frequently as that of wild caught SBT while maintaining total dietary mercury intake below national recommendations.

  20. Standardization of a geo-referenced fishing data set for the Indian Ocean bigeye tuna, Thunnus obesus (1952-2014)

    NASA Astrophysics Data System (ADS)

    Wibawa, Teja A.; Lehodey, Patrick; Senina, Inna

    2017-02-01

    Geo-referenced catch and fishing effort data of the bigeye tuna fisheries in the Indian Ocean over 1952-2014 were analyzed and standardized to facilitate population dynamics modeling studies. During this 62-year historical period of exploitation, many changes occurred both in the fishing techniques and the monitoring of activity. This study includes a series of processing steps used for standardization of spatial resolution, conversion and standardization of catch and effort units, raising of geo-referenced catch into nominal catch level, screening and correction of outliers, and detection of major catchability changes over long time series of fishing data, i.e., the Japanese longline fleet operating in the tropical Indian Ocean. A total of 30 fisheries were finally determined from longline, purse seine and other-gears data sets, from which 10 longline and 4 purse seine fisheries represented 96 % of the whole historical geo-referenced catch. Nevertheless, one-third of total nominal catch is still not included due to a total lack of geo-referenced information and would need to be processed separately, accordingly to the requirements of the study. The geo-referenced records of catch, fishing effort and associated length frequency samples of all fisheries are available at doi:10.1594/PANGAEA.864154.

  1. Fin spine bone resorption in atlantic bluefin tuna, Thunnus thynnus, and comparison between wild and captive-reared specimens.

    PubMed

    Santamaria, Nicoletta; Bello, Giambattista; Pousis, Chrysovalentinos; Vassallo-Agius, Robert; de la Gándara, Fernando; Corriero, Aldo

    2015-01-01

    Bone resorption in the first spine of the first dorsal fin of Atlantic bluefin tuna (ABFT) has long been considered for age estimation studies. In the present paper spine bone resorption was assessed in wild (aged 1 to 13 years) and captive-reared (aged 2 to 11 years) ABFT sampled from the Mediterranean Sea. Total surface (TS), solid surface (SS) and reabsorbed surface (RS) were measured in spine transverse sections in order to obtain proportions of SS and RS. The spine section surface was found to be isometrically correlated to the fish fork length by a power equation. The fraction of solid spine bone progressively decreased according to a logarithmic equation correlating SS/TS to both fish size and age. The values ranged from 57% in the smallest examined individuals to 37% in the largest specimens. This phenomenon was further enhanced in captive-reared ABFT where SS/TS was 22% in the largest measured specimen. The difference between the fraction of SS of wild and captive-reared ABFT was highly significant. In each year class from 1- to 7-year-old wild specimens, the fraction of spine reabsorbed surface was significantly higher in specimens collected from March to May than in those sampled during the rest of the year. In 4-year-old fish the normal SS increase during the summer did not occur, possibly coinciding with their first sexual maturity. According to the correlations between SS/TS and age, the rate of spine bone resorption was significantly higher, even almost double, in captive-reared specimens. This could be attributed to the wider context of systemic dysfunctions occurring in reared ABFT, and may be related to a number of factors, including nutritional deficiencies, alteration of endocrine profile, cortisol-induced stress, and loss of spine functions during locomotion in rearing conditions.

  2. Fin Spine Bone Resorption in Atlantic Bluefin Tuna, Thunnus thynnus, and Comparison between Wild and Captive-Reared Specimens

    PubMed Central

    Santamaria, Nicoletta; Bello, Giambattista; Pousis, Chrysovalentinos; Vassallo-Agius, Robert; de la Gándara, Fernando; Corriero, Aldo

    2015-01-01

    Bone resorption in the first spine of the first dorsal fin of Atlantic bluefin tuna (ABFT) has long been considered for age estimation studies. In the present paper spine bone resorption was assessed in wild (aged 1 to 13 years) and captive-reared (aged 2 to 11 years) ABFT sampled from the Mediterranean Sea. Total surface (TS), solid surface (SS) and reabsorbed surface (RS) were measured in spine transverse sections in order to obtain proportions of SS and RS. The spine section surface was found to be isometrically correlated to the fish fork length by a power equation. The fraction of solid spine bone progressively decreased according to a logarithmic equation correlating SS/TS to both fish size and age. The values ranged from 57% in the smallest examined individuals to 37% in the largest specimens. This phenomenon was further enhanced in captive-reared ABFT where SS/TS was 22% in the largest measured specimen. The difference between the fraction of SS of wild and captive-reared ABFT was highly significant. In each year class from 1- to 7-year-old wild specimens, the fraction of spine reabsorbed surface was significantly higher in specimens collected from March to May than in those sampled during the rest of the year. In 4-year-old fish the normal SS increase during the summer did not occur, possibly coinciding with their first sexual maturity. According to the correlations between SS/TS and age, the rate of spine bone resorption was significantly higher, even almost double, in captive-reared specimens. This could be attributed to the wider context of systemic dysfunctions occurring in reared ABFT, and may be related to a number of factors, including nutritional deficiencies, alteration of endocrine profile, cortisol-induced stress, and loss of spine functions during locomotion in rearing conditions. PMID:25751271

  3. [Vertical distribution of main species captured by tuna longline fishery in the southeast Pacific Ocean].

    PubMed

    Zhang, Yan-bo; Dai, Xiao-jie; Zhu, Jiang-feng; Gao, Chun-xia; Wu, Feng; Zheng, Xiao-chun

    2015-03-01

    Information of vertical distribution of longline-hook species is important for the development of effective measures to mitigate bycatch, and very helpful for better understanding of the oceanic ecosystem structure and implementation of ecosystem-based fisheries management. Based on depth data of longline hook and capture hook position of pelagic species, collected by on board scientific observer in the southeast Pacific Ocean from September 2013 to January 2014, shoaling rate of longline hook and vertical distribution of 14 pelagic species were analyzed. The results showed that the relative shoaling rate range of longline hook was 8.9% - 17.1%, and the average relative shoaling rate was 13.5%. The depth ranges of 14 capture species were different. The species with the deepest depth was Opah (Lampris guttatus), and the species with the shallowest depth was skipjack (Katsuwonus pelamis). Except for yellowfin tuna (Thunnus albacares) and striped marlin (Tetrapturus audax), the mean depth and depth distributions of bycatch species were significantly different from that of the targeted albacore tuna (Thunnus alalunga).

  4. [Fatty acid variation in yellowfin tuna, spotted weakfish and Florida pompano when submitted to six cooking techniques].

    PubMed

    Castro-González, María Isabel; Maafs-Rodríguez, Ana Gabriela; Romo Pérez-Gil, Fernando

    2013-03-01

    The aim of the present study was to analyze the effect of six cooking techniques (steamed, foiled, foiled with banana leaf, baked, microwave-cooked and light frying) in the fatty acid content of Thunnus albacore (yellowfin tuna), Cynoscionnebulosus (spotted weakfish) and Trachinotuscarolinus (Florida pompano). After cooking the fish fillets, fatty acid analyses were performed using gas chromatography. Total lipids increased in all cooking techniques in tunaand spotted weakfish. Saturated fatty acids of tuna and spotted weakfish increased in three cooking techniques, while in Florida pompano only gas oven raised their content. Lightly frying generated the highest content of n-3 in tuna and spotted weakfish, and the lowest in Florida pompano, specie that presented less variation. In tuna fish, the most recommended cooking techniques are foiled with aluminum and microwave oven; for spotted weakfish, foiled with banana leaf; while Florida pompano can be prepared using all cooking methods except gas oven. This information is useful to enrich data from chemical composition tables, in which concentrations are usually presented in raw food.

  5. Effect of Storage Temperature on the Outgrowth and Toxin Production of Staphylococcus aureus in Freeze-Thawed Precooked Tuna Meat.

    PubMed

    Kataoka, Ai; Enache, Elena; Napier, Carla; Hayman, Melinda; Weddig, Lisa

    2016-04-01

    The aim of this study was to determine the time for a 3-log CFU/g outgrowth of Staphylococcus aureus and its toxin production in previously frozen precooked tuna meat (albacore [Thunnus alalunga] prepared as loin, chunk, and flake or skipjack [Katsuwonus pelamis] prepared as chunk and flake) held either at 21 or 27°C. A five-strain cocktail of enterotoxin-producing S. aureus was surface inoculated with ∼10(3) CFU/g onto tuna samples. The experimental time-temperature conditions were designed to mimic common industry holding conditions. After a 3-h incubation at 37°C, inoculated samples were individually vacuum sealed and stored at 20°C for 4 weeks. Following frozen storage, samples were thawed to the target temperature (21 or 27°C) and then incubated aerobically. Growth of S. aureus in tuna was then monitored using Baird Parker agar; simultaneously, aerobic plate counts, enterotoxin production, and sensory profile (color and odor) were determined. The results showed that the time for a 3-log CFU/g increase was >20 h at 21°C and 8 to 12 h at 27°C for albacore, with toxin production observed at 14 to 16 h at 21°C and at 8 h at 27°C. A 3-log CFU/g increase for skipjack occurred at 22 to 24 h at 21°C and at 10 to 14 h at 27°C. The toxin production in skipjack started at 20 to 22 h at 21°C and at 8 to 10 h at 27°C. Toxin production was observed before a 3-log increase was achieved in albacore samples at 21°C. Under all conditions, toxins were detected when the cell density of S. aureus was 6 log CFU/g. Overall, significantly faster S. aureus growth was observed in albacore compared with skipjack (P < 0.05), possibly owing to differences in sample composition (e.g., pH and salt content). The data developed from this study can be used by the tuna industry to model the growth and enterotoxin production of S. aureus and to design manufacturing controls that ensure food safety.

  6. Effect of oceanographic parameters on daily albacore catches in the Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Goñi, Nicolas; Didouan, Canelle; Arrizabalaga, Haritz; Chifflet, Marina; Arregui, Igor; Goikoetxea, Nerea; Santiago, Josu

    2015-03-01

    In recent years, albacore (Thunnus alalunga) catches decreased strongly in the Eastern part of the Bay of Biscay. In order to understand the drivers of local albacore catches by fisheries in this area, we analyzed the influence of temperature, salinity and trophic parameters on albacore daily catches by three fleets (baitboat, trolling line and pelagic trawling) traditionally operating in the Bay of Biscay and its surrounding waters. For this, we used oceanographic data obtained from the operational model Regional Ocean Model System (ROMS), for each catch date and location. A Principal Component Analysis performed on these oceanographic data, on Julian day, latitude and longitude, yielded three synthetic variables used as explanatory variables in Generalized Additive Models (GAMs). The first one synthesized most of the variability related to temperature, plankton concentration and longitude. The second one synthesized most of the variability related to surface mixing associated with a seasonal trend. The third one synthesized most of the variability related to salinity and latitude. GAMs revealed a non-linear effect of salinity and latitude on daily catches for all fleets. The effect of mixing was negative for surface gear catches and positive for trawl catches. The trophic and planktonic component had a clear influence only on baitboat and trolling catches. The results are discussed in terms of albacore habitat preferences, vertical distribution and feeding behavior. We suggest that these environmental influences should be considered when using albacore catch data for stock assessment and extrapolating the effects of climate change on albacore abundance in the Bay of Biscay.

  7. Analysis of carbon monoxide in commercially treated tuna (Thunnus spp.) and mahi-mahi (Coryphaena hippurus) by gas chromatography/mass spectrometry.

    PubMed

    Anderson, Collin R; Wu, Wen-Hsin

    2005-09-07

    A simple and confirmative method for quantitative determination of carbon monoxide in tuna and mahi-mahi tissues using GC/MS, following chemical liberation of CO into headspace, is described. Carbon monoxide in recent years has been employed by the fishery industry to preserve fresh appearance in selected species of finfish during frozen storage, particularly in vacuum-packaged products. Indigenous CO contents of fresh Ahi tuna and mahi-mahi were examined using the method described in this study and found to be close to or less than 150 and 100 ng/g, respectively. Commercially CO-treated, vacuum-packaged tuna from multiple sources consistently showed CO level near or greater than 1 mug/g, while CO level in the only CO-treated frozen mahi-mahi sample was in the 500 ng/g range. The difference between untreated and treated specimens was in the range of 1 order of magnitude and thus suggested an easy quantitative and confirmative method of CO using widely available instrumentation that may be potentially useful for regulatory purpose in determining whether a commercially available product has been exposed to CO even if not labeled as such.

  8. Development of Formaldehyde Biosensor for Determination of Formalin in Fish Samples; Malabar Red Snapper (Lutjanus malabaricus) and Longtail Tuna (Thunnus tonggol)

    PubMed Central

    Noor Aini, Bohari; Siddiquee, Shafiquzzaman; Ampon, Kamaruzaman

    2016-01-01

    Electrochemical biosensors are widely recognized in biosensing devices due to the fact that gives a direct, reliable, and reproducible measurement within a short period. During bio-interaction process and the generation of electrons, it produces electrochemical signals which can be measured using an electrochemical detector. A formaldehyde biosensor was successfully developed by depositing an ionic liquid (IL) (e.g., 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([EMIM][Otf])), gold nanoparticles (AuNPs), and chitosan (CHIT), onto a glassy carbon electrode (GCE). The developed formaldehyde biosensor was analyzed for sensitivity, reproducibility, storage stability, and detection limits. Methylene blue was used as a redox indicator for increasing the electron transfer in the electrochemical cell. The developed biosensor measured the NADH electron from the NAD+ reduction at a potential of 0.4 V. Under optimal conditions, the differential pulse voltammetry (DPV) method detected a wider linear range of formaldehyde concentrations from 0.01 to 10 ppm within 5 s, with a detection limit of 0.1 ppm. The proposed method was successfully detected with the presence of formalin in fish samples, Lutjanus malabaricus and Thunnus Tonggol. The proposed method is a simple, rapid, and highly accurate, compared to the existing technique. PMID:27376338

  9. The Real maccoyii: Identifying Tuna Sushi with DNA Barcodes – Contrasting Characteristic Attributes and Genetic Distances

    PubMed Central

    Lowenstein, Jacob H.; Amato, George; Kolokotronis, Sergios-Orestis

    2009-01-01

    Background The use of DNA barcodes for the identification of described species is one of the least controversial and most promising applications of barcoding. There is no consensus, however, as to what constitutes an appropriate identification standard and most barcoding efforts simply attempt to pair a query sequence with reference sequences and deem identification successful if it falls within the bounds of some pre-established cutoffs using genetic distance. Since the Renaissance, however, most biological classification schemes have relied on the use of diagnostic characters to identify and place species. Methodology/Principal Findings Here we developed a cytochrome c oxidase subunit I character-based key for the identification of all tuna species of the genus Thunnus, and compared its performance with distance-based measures for identification of 68 samples of tuna sushi purchased from 31 restaurants in Manhattan (New York City) and Denver, Colorado. Both the character-based key and GenBank BLAST successfully identified 100% of the tuna samples, while the Barcode of Life Database (BOLD) as well as genetic distance thresholds, and neighbor-joining phylogenetic tree building performed poorly in terms of species identification. A piece of tuna sushi has the potential to be an endangered species, a fraud, or a health hazard. All three of these cases were uncovered in this study. Nineteen restaurant establishments were unable to clarify or misrepresented what species they sold. Five out of nine samples sold as a variant of “white tuna” were not albacore (T. alalunga), but escolar (Lepidocybium flavorunneum), a gempylid species banned for sale in Italy and Japan due to health concerns. Nineteen samples were northern bluefin tuna (T. thynnus) or the critically endangered southern bluefin tuna (T. maccoyii), though nine restaurants that sold these species did not state these species on their menus. Conclusions/Significance The Convention on International Trade

  10. Trophic ecology of Atlantic Bluefin Tuna (Thunnus thynnus) [corrected] larvae from the Gulf of Mexico and NW Mediterranean spawning grounds: A Comparative Stable Isotope Study.

    PubMed

    Laiz-Carrión, Raúl; Gerard, Trika; Uriarte, Amaya; Malca, Estrella; Quintanilla, José María; Muhling, Barbara A; Alemany, Francisco; Privoznik, Sarah L; Shiroza, Akihiro; Lamkin, John T; García, Alberto

    2015-01-01

    The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C) as trophic indicators for Atlantic bluefin tuna larvae (BFT) (6-10 mm standard length) in the highly contrasting environmental conditions of the Gulf of Mexico (GOM) and the Balearic Sea (MED). These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton-zooplankton-larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae.

  11. Total mercury in canned tuna sold in Canada in 2006.

    PubMed

    Dabeka, Robert W; Mckenzie, Arthur D; Forsyth, Donald S

    2014-01-01

    Total mercury was measured in 156 composites prepared from 936 samples of canned tuna sold in Canada in 2006. Each composite comprised a single brand. Yellowfin tuna contained the lowest concentrations, averaging 0.066 mg/kg. Skipjack tuna contained slightly higher concentrations, averaging 0.132 mg/kg. The highest average concentration was found in the Albacore tuna: mean 0.325 mg/kg, range 0.174-0.507 mg/kg. The second highest concentration among the 49 albacore composites was 0.469 mg/kg. There were 72 composites for which the type of tuna was not specified. The mercury in these averaged 0.095 mg/kg and ranged from 0.016 to 0.237 mg/kg.

  12. Relationship of Northeast Atlantic albacore juveniles with surface thermal and chlorophyll-a fronts

    NASA Astrophysics Data System (ADS)

    Sagarminaga, Y.; Arrizabalaga, H.

    2014-09-01

    When the spring seasonal warming starts, North Atlantic albacore (Thunnus alalunga) juveniles and pre-adults perform a trophic migration to the northeastern Atlantic, to the Bay of Biscay, and to the southeast of Ireland. During this migration, albacore juveniles are mainly exploited by Spanish trolling and baitboat fleets. The present study analyzes the relationship between the albacore spatio-temporal distribution and the upper surface horizontal fronts in their migration paths and destinations. For this, albacore catches from personal fishing logbooks from Basque trolling and live-bait fleets and daily MODIS AQUA Chlorophyll-a and SST products covering the period 2003-2005 have being used. Gradients have been calculated with the front algorithm proposed by Belkin and O'Reilly (2009). The approach used to study the relationship of catches location with frontal areas is based in the comparison of distributions of gradient magnitude around catch locations versus gradient magnitudes in a Monthly Occupation Area. The results obtained show that there is a high spatio- temporal variability of SST and Chl-a fronts in the area. SST and Chl-a fronts are not coincident in time or in space. However, there is a clear seasonal pattern of SST and Chl-a frontal activity in the area with a peak in July for SST gradient magnitudes and a peak in April for Chl-a gradient magnitudes. The relationship of albacore juvenile catches with high gradient magnitude areas is different according to the months and fleets analysed. In general, there is no evidence of consistent adherence of albacore catches to areas with higher SST gradients. However, results suggest a potential association between both fleets catches and Chl-a high gradient magnitude areas in August and September.

  13. The Southern Oscillation, Hypoxia, and the Eastern Pacific Tuna Fishery

    NASA Astrophysics Data System (ADS)

    Webster, D.; Kiefer, D.; Lam, C. H.; Harrison, D. P.; Armstrong, E. M.; Hinton, M.; Luo, L.

    2012-12-01

    The Eastern Pacific tuna fishery, which is one of the world's major fisheries, covers thousands of square kilometers. The vessels of this fishery are registered in more than 30 nations and largely target bigeye (Thunnus obesus), skipjack (Katsuwonus pelamis), and yellowfin (T. albacores) tuna. In both the Pelagic Habitat Analysis Module project, which is sponsored by NASA, and the Fishscape project, which is sponsored by NSF, we have attempted to define the habitat of the three species by matching a 50 year time series on fish catch and effort with oceanographic information obtained from satellite imagery and from a global circulation model. The fishery time series, which was provided by the Inter-American Tropical Tuna Commission, provided spatial maps of catch and effort at monthly time steps; the satellite imagery of the region consisted of sea surface temperature, chlorophyll, and height from GHRSST, SEAWiFS, and AVISO products, and the modeled flow field at selected depths was output from ECCO-92 simulations from 1992 to present. All information was integrated and analyzed within the EASy marine geographic information system. This GIS will also provides a home for the Fishscape spatial simulation model of the coupled dynamics of the ocean, fish, fleets, and markets. This model will then be applied to an assessment of the potential ecological and economic impacts of climate change, technological advances in fleet operations, and increases in fuel costs. We have determined by application of EOF analysis that the ECCO-2 simulation of sea surface height fits well with that of AVISO imagery; thus, if driven properly by predictions of future air-sea exchange, the model should provide good estimates of circulation patterns. We have also found that strong El Nino events lead to strong recruitment of all three species and strong La Nina events lead to weak recruitment. Finally, we have found that the general spatial distribution of the Eastern Pacific fishing grounds

  14. Identification of five highly priced tuna species by quantitative real-time polymerase chain reaction.

    PubMed

    Liu, Shasha; Xu, Kunhua; Wu, Zhigang; Xie, Xiao; Feng, Junli

    2016-09-01

    Tunas are economically important fishery worldwide, and are often used for commercial processed production. For effective fishery management and protection of consumers' rights, it is important to develop a molecular method to identify species in canned tuna products rapidly and reliably. Here, we have developed a duplex quantitative real-time PCR (qPCR) for identification of five highly priced tuna species (Thunnus maccoyii, Thunnus obesus, Thunnus albacares, Thunnus alalunga and Katsuwonus pelamis) from processed as well as fresh fish. After amplification and sequencing of seven genetic markers commonly used for species identification, 16S rDNA and control region (CR) of mitochondrial DNA were selected as the reference gene markers for genus Thunnus and tuna species identification, respectively. Subsequently, a 73 bp fragment of 16S rDNA and 85-99 bp fragment of CR were simultaneously amplified from each target species by qPCR. The qPCR efficiency of each reaction was calculated according to the standard curves, and the method was validated by amplification DNA extracted from single or mixed tuna specimen. The developed duplex qPCR system was applied to authenticate species of 14 commercial tuna products successfully, which demonstrated it was really a useful and academic technique to identify highly priced tuna species.

  15. Tuna Longline Fishing around West and Central Pacific Seamounts

    PubMed Central

    Morato, Telmo; Hoyle, Simon D.; Allain, Valerie; Nicol, Simon J.

    2010-01-01

    Background Seamounts have been identified as aggregating locations for pelagic biodiversity including tuna; however the topography and prevailing oceanography differ between seamounts and not all are important for tuna. Although a relatively common feature in oceanic ecosystems, little information is available that identifies those that are biologically important. Improved knowledge offers opportunities for unique management of these areas, which may advance the sustainable management of oceanic resources. In this study, we evaluate the existence of an association between seamounts and tuna longline fisheries at the ocean basin scale, identify significant seamounts for tuna in the western and central Pacific Ocean, and quantify the seamount contribution to the tuna longline catch. Methodology/Principal Findings We use data collected for the Western and Central Pacific Ocean for bigeye, yellowfin, and albacore tuna at the ocean basin scale. GLMs were applied to a coupled dataset of longline fisheries catch and effort, and seamount location information. The analyses show that seamounts may be associated with an annual longline combined catch of 35 thousand tonnes, with higher catch apparent for yellowfin, bigeye, and albacore tuna on 17%, 14%, and 14% of seamounts respectively. In contrast 14%, 18%, and 20% of seamounts had significantly lower catches for yellowfin, bigeye and albacore tuna respectively. Studying catch data in relation to seamount positions presents several challenges such as bias in location of seamounts, or lack of spatial resolution of fisheries data. Whilst we recognize these limitations the criteria used for detecting significant seamounts were conservative and the error in identification is likely to be low albeit unknown. Conclusions/Significance Seamounts throughout the study area were found to either enhance or reduce tuna catch. This indicates that management of seamounts is important Pacific-wide, but management approaches must take

  16. Spatial Patterns and Temperature Predictions of Tuna Fatty Acids: Tracing Essential Nutrients and Changes in Primary Producers.

    PubMed

    Pethybridge, Heidi R; Parrish, Christopher C; Morrongiello, John; Young, Jock W; Farley, Jessica H; Gunasekera, Rasanthi M; Nichols, Peter D

    2015-01-01

    Fatty acids are among the least understood nutrients in marine environments, despite their profile as key energy components of food webs and that they are essential to all life forms. Presented here is a novel approach to predict the spatial-temporal distributions of fatty acids in marine resources using generalized additive mixed models. Fatty acid tracers (FAT) of key primary producers, nutritional condition indices and concentrations of two essential long-chain (≥C20) omega-3 fatty acids (EFA) measured in muscle of albacore tuna, Thunnus alalunga, sampled in the south-west Pacific Ocean were response variables. Predictive variables were: location, time, sea surface temperature (SST) and chlorophyll-a (Chla), and phytoplankton biomass at time of catch and curved fork length. The best model fit for all fatty acid parameters included fish length and SST. The first oceanographic contour maps of EFA and FAT (FATscapes) were produced and demonstrated clear geographical gradients in the study region. Predicted changes in all fatty acid parameters reflected shifts in the size-structure of dominant primary producers. Model projections show that the supply and availability of EFA are likely to be negatively affected by increases in SST especially in temperate waters where a 12% reduction in both total fatty acid content and EFA proportions are predicted. Such changes will have large implications for the availability of energy and associated health benefits to high-order consumers. Results convey new concerns on impacts of projected climate change on fish-derived EFA in marine systems.

  17. Relationships between tuna catch and variable frequency oceanographic conditions

    NASA Astrophysics Data System (ADS)

    Ormaza-González, Franklin Isaac; Mora-Cervetto, Alejandra; María Bermúdez-Martínez, Raquel

    2016-08-01

    Skipjack (Katsuwunus pelamis), yellow fin (Thunnus albacares) and albacore (Thunnus alulunga) tunas landed in the Eastern Pacific Ocean (EPO) countries and Ecuador were correlated to the Indexes Oceanic El Niño (ONI) and Multivariate Enso Index (MEI). The temporal series 1983-2012, and 1977-1999 (warm Pacific Decadal Oscillation, PDO), and 2000-2012 (cold PDO) were analyzed. Linear correlation showed that at least 11 % of the total landings were associated with the MEI, with a slightly negative gradient from cold to warm conditions. When non-linear regression (n = 6), the R2 was higher up to 0.304 (MEI, r = 0.551). The correlation shows high spread from -0.5 to +0.5 for both MEI/ONI; the highest landings occurred at 0.34-0.45; both indexes suggested that at extreme values < -1.0 and > 1.1 total landings tend to decrease. Landings were associated up to 21.9 % (MEI) in 2000-2012, 1983-1999 rendered lower R2 (< 0.09); i.e., during cold PDO periods there was a higher association between landings and oceanographic conditions. For the non-linear regression (n = 6) a R2 of 0.374 (MEI) and 0.408 (ONI) were registered, for the 2000-2012, a higher R2 was observed in 1983-1999, 0.443 and 0.711 for MEI and ONI respectively, suggesting that is better to analyze split series (1983-1999, 2000-2012) than as a whole (1983-2012), due to noise produced by the transition from hot to cold PDOs. The highest landings were in the range -0.2 to 0.5 for MEI/ONI. The linear regression of skipjack landings in Ecuador gave an R2 of 0.140 (MEI) and 0.066 (ONI) and the non-linear were 0.440 and 0.183 respectively. Total landings in the EPO associated to oceanographic events of high and low frequencies could be used somehow as predictors of the high El Niño o La Niña. There is a clear evidence that tuna fish biomass are at higher levels when the PDO is on cold phase (2000-2030) and vice versa on warm phase (1980-1999). The analysis of the skipjack catch per unit effort (CPUE) on floating

  18. Expression analysis of the Atlantic bluefin tuna (Thunnus thynnus) pro-inflammatory cytokines, IL-1β, TNFα1 and TNFα2 in response to parasites Pseudocycnus appendiculatus (Copepoda) and Didymosulcus katsuwonicola (Digenea).

    PubMed

    Pleić, Ivana Lepen; Bušelić, Ivana; Trumbić, Željka; Bočina, Ivana; Šprung, Matilda; Mladineo, Ivona

    2015-08-01

    Pro-inflammatory cytokines play an important role in teleost defence against numerous types of pathogens, therefore are often used as biomarkers during various infections. In order to evaluate Atlantic bluefin tuna IL-1β, TNFα1 and TNFα2 induction by PAMPs, we quantified their expression during in vitro stimulation of peripheral blood leukocytes by LPS and Poly I:C. Furthermore, their role in acute and chronic parasitic infection was examined during natural infection of Pseudocycnus appendiculatus (Copepoda) and Didymosulcus katsuwonicola (Digenea), as well as during leukocyte exposure to total protein extracts isolated from two parasite species. Induction of ABT IL-1β and TNFα2 by PAMPs and protein extracts from D. katsuwonicola and P. appendiculatus, as well as during natural infection with two parasites, suggests these cytokines play an important role in inflammation, being engaged in controlling parasite infections, in contrast to ABT TNFα1. Cellular innate response to the digenean D. katsuwonicola showed rather chronic character, resulting with parasite encapsulation in connective tissue. Mast cells, eosinophils, goblet cells, and occasional rodlet cells found at the site of infection, along with the induction of TNFα2, suggest the presence of a moderate inflammatory reaction that fails to seriously endanger digenean existence. In contrast, copepod P. appendiculatus, attached to the gill epithelium by clamping, caused direct tissue disruption with undergoing necrotic or apoptotic processes, and extensive proliferation of rodlet and goblet cells. Differential expression patterns of target cytokines in tissue surrounding two parasites and in vitro PBL model suggest that quality and quantity of tuna immune response is conditioned by parasite adaptive mechanisms and pathogenicity.

  19. Tuna cornea as biomaterial for cardiac applications.

    PubMed

    Parravicini, Roberto; Cocconcelli, Flavio; Verona, Alessandro; Parravicini, Valeriano; Giuliani, Enrico; Barbieri, Alberto

    2012-01-01

    Among available biomaterials, cornea is almost completely devoid of cells and is composed only of collagen fibers oriented in an orderly pattern, which contributes to low antigenicity. Thunnus thynnus, the Atlantic bluefin tuna, is a fish with large eyes that can withstand pressures of approximately 10 MPa. We evaluated the potential of this tuna cornea in cardiac bioimplantation. Eyes from freshly caught Atlantic bluefin tuna were harvested and preserved in a fixative solution. Sterilized samples of corneal stroma were embedded in paraffin and stained with hematoxylin and eosin, and the histologic features were studied. Physical and mechanical resistance tests were performed in comparison with bovine pericardial strips and porcine mitral valves. Corneal material was implanted subcutaneously in 7 rats, to evaluate in vivo calcification rates. Mitral valves made from tuna corneal leaflets were implanted in 9 sheep. We found that the corneal tissue consisted only of parallel collagen fibers without evidence of vascular or neural structures. In tensile strength, the tuna corneal specimens were substantially similar to bovine pericardium. After 23 days, the rat-implanted samples showed no calcium or calcium salt deposition. Hydrodynamic and fatigue testing of valve prototypes yielded acceptable functional and long-term behavioral results. In the sheep, valvular performance was stable during the 180-day follow-up period, with no instrumental sign of calcification at the end of observation. We conclude that low antigenicity and favorable physical properties qualify tuna cornea as a potential material for durable bioimplantation. Further study is warranted.

  20. 50 CFR 660.702 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (Tetrapturus audax) swordfish (Xiphias gladius) Sharks: common thresher shark (Alopias vulpinus) pelagic thresher shark (Alopias pelagicus) bigeye thresher shark (Alopias superciliosus) shortfin mako or bonito shark (Isurus oxyrinchus) blue shark (Prionace glauca) Tunas: north Pacific albacore (Thunnus...

  1. Spatial Patterns and Temperature Predictions of Tuna Fatty Acids: Tracing Essential Nutrients and Changes in Primary Producers

    PubMed Central

    Pethybridge, Heidi R.; Parrish, Christopher C.; Morrongiello, John; Young, Jock W.; Farley, Jessica H.; Gunasekera, Rasanthi M.; Nichols, Peter D.

    2015-01-01

    Fatty acids are among the least understood nutrients in marine environments, despite their profile as key energy components of food webs and that they are essential to all life forms. Presented here is a novel approach to predict the spatial-temporal distributions of fatty acids in marine resources using generalized additive mixed models. Fatty acid tracers (FAT) of key primary producers, nutritional condition indices and concentrations of two essential long-chain (≥C20) omega-3 fatty acids (EFA) measured in muscle of albacore tuna, Thunnus alalunga, sampled in the south-west Pacific Ocean were response variables. Predictive variables were: location, time, sea surface temperature (SST) and chlorophyll-a (Chla), and phytoplankton biomass at time of catch and curved fork length. The best model fit for all fatty acid parameters included fish length and SST. The first oceanographic contour maps of EFA and FAT (FATscapes) were produced and demonstrated clear geographical gradients in the study region. Predicted changes in all fatty acid parameters reflected shifts in the size-structure of dominant primary producers. Model projections show that the supply and availability of EFA are likely to be negatively affected by increases in SST especially in temperate waters where a 12% reduction in both total fatty acid content and EFA proportions are predicted. Such changes will have large implications for the availability of energy and associated health benefits to high-order consumers. Results convey new concerns on impacts of projected climate change on fish-derived EFA in marine systems. PMID:26135308

  2. Bioenergetics, Trophic Ecology, and Niche Separation of Tunas.

    PubMed

    Olson, R J; Young, J W; Ménard, F; Potier, M; Allain, V; Goñi, N; Logan, J M; Galván-Magaña, F

    Tunas are highly specialized predators that have evolved numerous adaptations for a lifestyle that requires large amounts of energy consumption. Here we review our understanding of the bioenergetics and feeding dynamics of tunas on a global scale, with an emphasis on yellowfin, bigeye, skipjack, albacore, and Atlantic bluefin tunas. Food consumption balances bioenergetics expenditures for respiration, growth (including gonad production), specific dynamic action, egestion, and excretion. Tunas feed across the micronekton and some large zooplankton. Some tunas appear to time their life history to take advantage of ephemeral aggregations of crustacean, fish, and molluscan prey. Ontogenetic and spatial diet differences are substantial, and significant interdecadal changes in prey composition have been observed. Diet shifts from larger to smaller prey taxa highlight ecosystem-wide changes in prey availability and diversity and provide implications for changing bioenergetics requirements into the future. Where tunas overlap, we show evidence of niche separation between them; resources are divided largely by differences in diet percentages and size ranges of prey taxa. The lack of long-term data limits the ability to predict impacts of climate change on tuna feeding behaviour. We note the need for systematic collection of feeding data as part of routine monitoring of these species, and we highlight the advantages of using biochemical techniques for broad-scale analyses of trophic relations. We support the continued development of ecosystem models, which all too often lack the regional-specific trophic data needed to adequately investigate climate and fishing impacts.

  3. Tuna aggregation and feeding near fronts observed in satellite imagery

    NASA Astrophysics Data System (ADS)

    Fiedler, Paul C.; Bernard, Hannah J.

    1987-08-01

    Stomach contents of albacore ( Thunnus alalunga) and skipjack ( Katsuwonus pelamis) caught off California in August 1983 showed they were feeding on juvenile northern anchovy ( Engraulis mordax), other fishes, and planktonic crustaceans. The distribution and diet of these predators were related to mesoscale frontal features visible in satellite sea surface temperature and phytoplankton pigment imagery. Albacore were caught in the vicinity of a filament of cold, pigment-rich surface water that varied with the intensity of coastal upwelling on time scales of several days. Stomachs of albacore caught closer to the filament contained relatively more juvenile anchovy and fewer pelagic red crabs ( Pleuroncodes planipes). Skipjack were caught in warm water in the Southern California Bight, north of their normal range due to El Nin˜o warming. They appeared to be feeding most successfully near the strong frontal boundary of a productive, cold water mass south of Pt. Conception, where dense patches of euphausiids were available. Both species were feeding near variable, mesoscale centers of high productivity where prey abundance may be enhanced.

  4. Weight dependence of arsenic concentration in the Arabian Sea tuna fish

    SciTech Connect

    Ashraf, M.; Jaffar, M.

    1988-02-01

    The objective of the present investigation was to estimate the arsenic concentration in the edible muscle of Thunnus thynnus and Thunnus toggel (hereafter called tuna and longtail tune) as they have great commercial value. These fish are widely available along the coastal line of Pakistan and are consumed abundantly in large bulk. Thus, it was felt justifiable on the basis of safety of human health that data, in the first instance, be obtained on arsenic concentration in tuna as a function of weight to check whether the metal distribution was species-specific or it depended on individual mode of development. The data, the first of the kind so far presented on the Arabian Sea tuna, would thus provide the required baseline quantitative information needed in future studies on the physiological processes regulating the distribution and uptake of arsenic by these and other species of fish common to the region.

  5. Mercury in canned tuna: white versus light and temporal variation.

    PubMed

    Burger, Joanna; Gochfeld, Michael

    2004-11-01

    There are abundant data and advisories for mercury levels in wild fish, but far fewer for commercial fish that compose a large majority of the fish most people eat. Until recently, relatively little attention has been devoted to examining mercury in canned tuna, despite its great importance in human diets. There is substantial media coverage of the benefits and risk from fish consumption, but few peer-reviewed data on canned tuna, the most commonly consumed fish in the United States. In this paper, we examine the levels of total mercury in canned tuna obtained from a New Jersey grocery store from 1998 to 2003, looking for temporal consistency within this data set and particularly for comparison with the Food and Drug Administration's 1991 study. We analyzed 168 cans individually for total mercury. All values are reported as parts per million (= microg/g) on a wet weight basis. In a subset of samples analyzed for total and inorganic mercury, the inorganic mercury was below detection levels; hence at least 89% of the mercury can be considered methylmercury. We found that white-style tuna had significantly more total mercury (mean 0.407 ppm) than light-style tuna (mean 0.118 ppm), presumably reflecting that "white" tuna is albacore, a species relatively larger than the skipjack tuna, which is commonly available as "light" or "chunk light." The maximum mercury in a can was 0.997 ppm, but 25% of white tuna samples exceeded 0.5 ppm. Data suggest a slight increase in levels since 1991, and mercury levels were significantly higher in 2001 than in other years. The mean level of mercury in white tuna (mean 0.407 ppm) was significantly higher than the mean value of 0.17 ppm currently used by the U.S. Food and Drug Administration (FDA) in its risk assessment and public information. There were no significant differences in mercury levels in tuna packed in oil compared to water. Draining contents had no effect on mercury levels, and the fluid, both oil and water, contained

  6. Effects of frozen storage on survival of Staphylococcus aureus and enterotoxin production in precooked tuna meat.

    PubMed

    Wu, Xulei; Su, Yi-Cheng

    2014-08-01

    This study investigated the survival of Staphylococcus aureus in precooked tuna meat for producing canned products during frozen storage (-20 ± 2 °C) as well as its growth and enterotoxin production at 35 to 37 °C after the storage. Samples (50 ± 5 g) of precooked albacore (loin, chunk, and flake) and skipjack (chunk and flake) tuna were inoculated with 5 enterotoxin-producing strains of S. aureus at a level of approximately 3.5 log CFU/g and individually packed in a vacuum bag after 3 h incubation at 35 to 37 °C. Vacuum-packed samples were stored in a freezer (-20 ± 2 °C) for 4 wk. The frozen samples were then thawed in 37 °C circulating water for 2 h and incubated at 35 to 37 °C for 22 h. Populations of S. aureus in all precooked tuna samples decreased slightly (<0.7 log CFU/g) after 4 wk of storage at -20 ± 2 °C, but increased rapidly once the samples were thawed and held at 35 to 37 °C. Total S. aureus counts in albacore and skipjack samples increased by greater than 3 log CFU/g after 6 and 8 h of exposure to 35 to 37 °C, respectively. All samples became spoiled after 10 h of exposure to 35 to 37 °C, while no enterotoxin was detected in any samples. However, enterotoxins were detected in albacore loin and other samples after 12 and 24 h of incubation at 35 to 37 °C, respectively. Frozen precooked tuna meat should be used for producing canned tuna within 6 to 8 h of thawing to avoid product spoilage and potential enterotoxin production by S. aureus in contaminated precooked tuna meat.

  7. Anthropogenic and naturally-produced organobrominated compounds in bluefin tuna from the Mediterranean Sea.

    PubMed

    Pena-Abaurrea, Miren; Weijs, Liesbeth; Ramos, Lourdes; Borghesi, Nicoletta; Corsolini, Simonetta; Neels, Hugo; Blust, Ronny; Covaci, Adrian

    2009-09-01

    Anthropogenic compounds, such as polybrominated diphenyl ethers (PBDEs), together with naturally-produced organobromines, such as methoxylated PBDEs (MeO-PBDEs), polybrominated hexahydroxanthene derivatives (PBHDs), 2,4,6-tribromoanisole (TBA) and a mixed halogenated monoterpene (MHC-1), were measured in muscle from 26 farmed and wild bluefin tuna (Thunnus thynnus) caught in the Mediterranean Sea. This species is ecological attractive because of the changes of geographic habitat throughout its long lifespan which affect its feeding. PBDE concentrations were similar between tuna samples of different groups (17-149 ng g(-1) lipid weight - lw in farmed tuna, 25-219 ng g(-1)lw in longline fished tuna and 26-126 ng g(-1)lw in net-fished tuna). However, higher concentrations of naturally-produced MeO-PBDEs and PBHDs were observed in the two types of wild tuna (longline fished and net-fished) compared to farmed tuna suggesting that wild tunas come easily in contact with sources of these compounds. In all cases PBHDs presented the highest contribution to the sum of organobromines (50% in farmed tuna and >90% in wild tuna). TBA was detected at low concentrations (<6 ng g(-1)lw), while MHC-1 was found at higher concentrations (up to 42 ng g(-1)lw) in farmed tuna. The estimated daily ingestion of PBDEs from tuna was 830 ng PBDEs day(-1), regardless of the origin of the tuna. While this value is approximately 600 times lower than the minimum risk level set by the US Department of Health and Human Services, it is approximately eight times higher than the total intake of PBDEs via diet, suggesting that consumption of tuna can add considerably to the total daily intake of PBDEs.

  8. A spatial ecosystem and populations dynamics model (SEAPODYM) Modeling of tuna and tuna-like populations

    NASA Astrophysics Data System (ADS)

    Lehodey, Patrick; Senina, Inna; Murtugudde, Raghu

    2008-09-01

    An enhanced version of the spatial ecosystem and population dynamics model SEAPODYM is presented to describe spatial dynamics of tuna and tuna-like species in the Pacific Ocean at monthly resolution over 1° grid-boxes. The simulations are driven by a bio-physical environment predicted from a coupled ocean physical-biogeochemical model. This new version of SEAPODYM includes expanded definitions of habitat indices, movements, and natural mortality based on empirical evidences. A thermal habitat of tuna species is derived from an individual heat budget model. The feeding habitat is computed according to the accessibility of tuna predator cohorts to different vertically migrating and non-migrating micronekton (mid-trophic) functional groups. The spawning habitat is based on temperature and the coincidence of spawning fish with presence or absence of predators and food for larvae. The successful larval recruitment is linked to spawning stock biomass. Larvae drift with currents, while immature and adult tuna can move of their own volition, in addition to being advected by currents. A food requirement index is computed to adjust locally the natural mortality of cohorts based on food demand and accessibility to available forage components. Together these mechanisms induce bottom-up and top-down effects, and intra- (i.e. between cohorts) and inter-species interactions. The model is now fully operational for running multi-species, multi-fisheries simulations, and the structure of the model allows a validation from multiple data sources. An application with two tuna species showing different biological characteristics, skipjack ( Katsuwonus pelamis) and bigeye ( Thunnus obesus), is presented to illustrate the capacity of the model to capture many important features of spatial dynamics of these two different tuna species in the Pacific Ocean. The actual validation is presented in a companion paper describing the approach to have a rigorous mathematical parameter optimization

  9. Tuna and swordfish catch in the U.S. northwest Atlantic longline fishery in relation to mesoscale eddies.

    PubMed

    Hsu, Ango C; Boustany, Andre M; Roberts, Jason J; Chang, Jui-Han; Halpin, Patrick N

    2015-11-01

    To analyze the effects of mesoscale eddies, sea surface temperature (SST), and gear configuration on the catch of Atlantic bluefin (Thunnus thynnus), yellowfin (Thunnus albacares), and bigeye tuna (Thunnus obesus) and swordfish (Xiphias gladius) in the U.S. northwest Atlantic longline fishery, we constructed multivariate statistical models relating these variables to the catch of the four species in 62 121 longline hauls made between 1993 and 2005. During the same 13-year period, 103 anticyclonic eddies and 269 cyclonic eddies were detected by our algorithm in the region 30-55°N, 30-80°W. Our results show that tuna and swordfish catches were associated with different eddy structures. Bluefin tuna catch was highest in anticyclonic eddies whereas yellowfin and bigeye tuna catches were highest in cyclonic eddies. Swordfish catch was found preferentially in regions outside of eddies. Our study confirms that the common practice of targeting tuna with day sets and swordfish with night sets is effective. In addition, bluefin tuna and swordfish catches responded to most of the variables we tested in the opposite directions. Bluefin tuna catch was negatively correlated with longitude and the number of light sticks used whereas swordfish catch was positively correlated with these two variables. We argue that overfishing of bluefin tuna can be alleviated and that swordfish can be targeted more efficiently by avoiding fishing in anticyclonic eddies and in near-shore waters and using more light sticks and fishing at night in our study area, although further studies are needed to propose a solid oceanography-based management plan for catch selection.

  10. PCB and OCP accumulation and evidence of hepatic alteration in the Atlantic bluefin tuna, T. thynnus, from the Mediterranean Sea.

    PubMed

    Maisano, Maria; Cappello, Tiziana; Oliva, Sabrina; Natalotto, Antonino; Giannetto, Alessia; Parrino, Vincenzo; Battaglia, Pietro; Romeo, Teresa; Salvo, Andrea; Spanò, Nunziacarla; Mauceri, Angela

    2016-10-01

    Persistent organic pollutants (POPs) are known to act as "obesogens", being fat-soluble and affecting lipid metabolism. The Atlantic bluefin tuna, Thunnus thynnus, are top pelagic predators prone to bioaccumulate and biomagnify environmental contaminants. This study aimed at evaluating POPs-induced ectopic lipid accumulation in liver of adult tuna from the Mediterranean Sea. PCBs and organochlorine pesticides were measured in tuna liver, and marked morphological changes observed, namely poorly compacted tissues, intense vacuolization, erythrocyte infiltration and presence of melanomacrophages. The expression of perilipin, a lipid-droplet marker, positively correlated with the gene expression of PPARγ, a master regulator of adipogenesis, and its heterodimeric partner, RXRα. Changes in metabolites involved in fatty acid biosynthesis and ketogenesis were also observed. Although male bluefin tuna appeared to be more sensitive than females to the adverse effects of environmental obesogens, the alterations observed in tuna liver of both sexes suggest a potential onset of hepatic steatosis.

  11. Trace elements in Thunnus thynnus from Mediterranean Sea and benefit-risk assessment for consumers.

    PubMed

    Di Bella, Giuseppa; Potortì, Angela Giorgia; Lo Turco, Vincenzo; Bua, Daniel; Licata, Patrizia; Cicero, Nicola; Dugo, Giacomo

    2015-01-01

    Trace elemental levels were determined by inductively coupled plasma-mass spectrometry in muscle, eggs and sperm of 23 Thunnus thynnus fishes collected from May to August 2013 in the Mediterranean Sea. Zn, Mn, Fe, Cu, Cr, Ni and Se content was compared with Recommended Daily Allowances. Cd, Hg and Pb concentrations were below the maximum limits fixed by the European Legislation. Tuna food safety was evaluated considering Tolerable Weekly Intake (TWI) or Provisional Tolerable Weekly Intake for As, Hg, Cd and Pb. Only BMDL01 data for As and Pb were calculated as established by the Joint FAO/WHO Expert Committed on Food Additives. The daily consumption of fresh tuna ensures a good intake of these elements. None of the tested samples surpassed the European maximum limits. Cd, Hg and Pb remained within safety margins, while As is slightly higher than the provisional TWI.

  12. Potential impact of climate change on the Intra-Americas Sea: Part 2. Implications for Atlantic bluefin tuna and skipjack tuna adult and larval habitats

    NASA Astrophysics Data System (ADS)

    Muhling, Barbara A.; Liu, Yanyun; Lee, Sang-Ki; Lamkin, John T.; Roffer, Mitchell A.; Muller-Karger, Frank; Walter, John F., III

    2015-08-01

    Increasing water temperatures due to climate change will likely have significant impacts on distributions and life histories of Atlantic tunas. In this study, we combined predictive habitat models with a downscaled climate model to examine potential impacts on adults and larvae of Atlantic bluefin tuna (Thunnus thynnus) and skipjack tuna (Katsuwonus pelamis) in the Intra-Americas Sea (IAS). An additional downscaled model covering the 20th century was used to compare habitat fluctuations from natural variability to predicted future changes under two climate change scenarios: Representative Concentration Pathway (RCP) 4.5 (medium-low) and RCP 8.5 (high). Results showed marked temperature-induced habitat losses for both adult and larval bluefin tuna on their northern Gulf of Mexico spawning grounds. In contrast, habitat suitability for skipjack tuna increased as temperatures warmed. Model error was highest for the two skipjack tuna models, particularly at higher temperatures. This work suggests that influences of climate change on highly migratory Atlantic tuna species are likely to be substantial, but strongly species-specific. While impacts on fish populations remain uncertain, these changes in habitat suitability will likely alter the spatial and temporal availability of species to fishing fleets, and challenge equilibrium assumptions of environmental stability, upon which fisheries management benchmarks are based.

  13. Heat resistance of histamine-producing bacteria in irradiated tuna loins.

    PubMed

    Enache, Elena; Kataoka, Ai; Black, D Glenn; Weddig, Lisa; Hayman, Melinda; Bjornsdottir-Butler, Kristin

    2013-09-01

    Consumption of foods high in biogenic amines leads to an illness known as histamine, or scombrotoxin, poisoning. The illness is commonly associated with consumption of fish with high levels of histamine ( $ 500 ppm). The objective of this study was to determine and compare the heat resistance of five histamine-producing bacteria in irradiated albacore tuna loins. Heat-resistance parameters (D- and z-values) were determined for Morganella morganii, Raoultella planticola, Hafnia alvei, and Enterobacter aerogenes. D- or z-values were not determined for Photobacterium damselae, which was the most heat-sensitive organism in this study. P. damselae declined > 5.9 log CFU/g after a heat treatment of 50°C for 10 min, 54°C for 3 min, and 56°C for 0.5 min. M. morganii was the most heat-resistant histamine-producing bacteria in albacore tuna loins, followed by E. aerogenes, H. alvei, and R. planticola. M. morganii and E. aerogenes had the highest D(50°C), 49.7 ± 17.57 and 51.8 ± 17.38 min, respectively. In addition, M. morganii had the highest D-values for all other temperatures (54, 56, and 58°C) tested. D- and zvalues were also determined for M. morganii in skipjack tuna. While no significant (P > 0.05) difference was observed between D(54°C) and D(56°C) of M. morganii in either albacore or skipjack tuna, the D(58°C) (0.4 ± 0.17 min) was significantly lower (P < 0.05) in skipjack than in albacore (0.9 ± 0.24 min). The z-values for all organisms tested were in the range of 3.2 to 3.8°C. This study suggests that heat treatment designed to control M. morganii in tuna loins is sufficient for controlling histamine-producing bacteria in canned-tuna processing environments.

  14. 50 CFR 600.530 - Pacific albacore fishery.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Pacific albacore fishery. 600.530 Section 600.530 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MAGNUSON-STEVENS ACT PROVISIONS Foreign Fishing § 600.530 Pacific...

  15. 50 CFR 600.530 - Pacific albacore fishery.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Pacific albacore fishery. 600.530 Section 600.530 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE MAGNUSON-STEVENS ACT PROVISIONS Foreign Fishing § 600.530 Pacific...

  16. Tuna Species Substitution in the Spanish Commercial Chain: A Knock-On Effect

    PubMed Central

    Gordoa, Ana; Carreras, Gustavo; Sanz, Nuria; Viñas, Jordi

    2017-01-01

    Intentional mislabelling of seafood is a widespread problem, particularly with high-value species like tuna. In this study we examine tuna mislabelling, deliberate species substitution, types of substitution and its impact on prices. The survey covered the commercial chain, from Merca-Barna to fishmongers and restaurants in the Spanish Autonomous Community of Catalonia. To understand the geographic extent of the problem we also sampled Merca-Madrid, Europe’s biggest fish market, and Merca-Málaga for its proximity to the bluefin tuna migratory route and trap fishery. Monthly surveys were carried out over one year. The results showed a high deficiency in labelling: 75% of points of sale and 83% of restaurants did not specify the species, and in those cases the name of the species had to be asked. A total of 375 samples were analysed genetically, the largest dataset gathered in Europe so far. The identified species were Thunnus albacares, Thunnus thynnus and Thunnus obesus. Species substitution began at suppliers, with 40% of observed cases, increasing to 58% at fishmongers and 62% at restaurants. The substitution was mainly on bluefin tuna (T. thynnus), 73% of cases. At restaurants, only during the bluefin fishing season, we observed a decrease of Bluefin tuna substitution and an increase of reverse substitution revealing some illegal fishing. The effect of species substitution on species prices was relevant: T. obesus increased its price by around €12 kg-1 when it was sold as bluefin. In view of the deficiency of labelling, the abuse of generic names and the lack of the bluefin catch document, we conclude that the Spanish regulations are ineffective, highlighting the need for policy execution, and the urgent need for information campaigns to Spanish consumers. PMID:28125686

  17. Tuna Species Substitution in the Spanish Commercial Chain: A Knock-On Effect.

    PubMed

    Gordoa, Ana; Carreras, Gustavo; Sanz, Nuria; Viñas, Jordi

    2017-01-01

    Intentional mislabelling of seafood is a widespread problem, particularly with high-value species like tuna. In this study we examine tuna mislabelling, deliberate species substitution, types of substitution and its impact on prices. The survey covered the commercial chain, from Merca-Barna to fishmongers and restaurants in the Spanish Autonomous Community of Catalonia. To understand the geographic extent of the problem we also sampled Merca-Madrid, Europe's biggest fish market, and Merca-Málaga for its proximity to the bluefin tuna migratory route and trap fishery. Monthly surveys were carried out over one year. The results showed a high deficiency in labelling: 75% of points of sale and 83% of restaurants did not specify the species, and in those cases the name of the species had to be asked. A total of 375 samples were analysed genetically, the largest dataset gathered in Europe so far. The identified species were Thunnus albacares, Thunnus thynnus and Thunnus obesus. Species substitution began at suppliers, with 40% of observed cases, increasing to 58% at fishmongers and 62% at restaurants. The substitution was mainly on bluefin tuna (T. thynnus), 73% of cases. At restaurants, only during the bluefin fishing season, we observed a decrease of Bluefin tuna substitution and an increase of reverse substitution revealing some illegal fishing. The effect of species substitution on species prices was relevant: T. obesus increased its price by around €12 kg-1 when it was sold as bluefin. In view of the deficiency of labelling, the abuse of generic names and the lack of the bluefin catch document, we conclude that the Spanish regulations are ineffective, highlighting the need for policy execution, and the urgent need for information campaigns to Spanish consumers.

  18. Application of the Oxidation-Reduction Potential (ORP) for Pre-grading Tuna Freshness On-board

    NASA Astrophysics Data System (ADS)

    Cheevaporanapivat, Mongkol; Sakai, Hisaharu; Mine, Yuuji; Watanabe, Manabu; Suzuki, Toru

    Application of ORP as a rapid indicator for grading tuna's freshness on the ship was studied. The long line trawling process was used for catching the sample tuna in the South Pacific Ocean. All captured sample tuna were weighed, gender identified and investigated for their mortality, then measured ORP and K value. Three species of tuna were caught: blue marlin (Makaira mazara), yellow fin tuna (Thunnus albacares), and swordfish (Xiphia gladius). Most of the fish captured were male and they had been dead after picking onboard. The measured ORP values of blue marlin varied in the range of 0.295-0.362 Volt, with pH between 5.35-5.84. Both ORP and pH of swordfish was similar to that of blue marlin. But for yellow fin tuna, the ORP value was about the same as blue marlin while its pH was significantly higher. ORP value in all species tended to increase with pH of the fish meat decrease. It is interesting that ORP value of tuna increased in correlation with K value. These results suggested that ORP and pH change, which are measured in the short time, are the effective indicators for grading tuna's freshness on-board.

  19. Total mercury in fresh and processed tuna marketed in Galicia (NW Spain) in relation to dietary exposure.

    PubMed

    García, M Ángeles; Núñez, Ricardo; Alonso, Julián; Melgar, M Julia

    2016-12-01

    Mercury is a toxic trace metal, which can accumulate to levels threatening human and environmental health. In this study, contents of total mercury have been determined by ICP-MS spectrometry in fresh and processed tuna (110 samples) purchased from supermarkets in NW Spain. Mercury was present in all samples analyzed; however, only one sample of fresh tuna (1.070 mg kg(-1) wet weight (w.w.)) slightly exceeded the limit of the EU (1.0 mg kg(-1) w.w.). The average mercury concentration in processed tuna was lower than fresh, 0.306 mg kg(-1) w.w., and ranged from 0.080 to 0.715 mg kg(-1) w.w. Results were compared with literature data. In regard to the three types of preparation-packaging media for canned tuna, total Hg content was found in the following order: olive oil > natural > pickled sauce; the last showed significant statistical differences (p < 0.01) with the other two preparations. Between the two evaluated canned tuna species, significant statistical differences (p = 0.008) were observed and Thunnus alalunga presented a greater mean content (0.332 ± 0.114 mg kg(-1) w.w.) compared to Thunnus albacares (0.266 ± 0.171 mg kg(-1) w.w.).Taking into account the AESAN recommendation for adults and children, as well as the EU regulations and the tuna consumption by the Spanish population, the Hg levels obtained in this study pose no risk to consumer health. However, additional studies, a monitoring process, and efforts to reduce Hg concentration in tuna would be necessary, as well as considering other sources of exposure to Hg.

  20. A Full Lifecycle Bioenergetic Model for Bluefin Tuna

    PubMed Central

    Jusup, Marko; Klanjscek, Tin; Matsuda, Hiroyuki; Kooijman, S. A. L. M.

    2011-01-01

    We formulated a full lifecycle bioenergetic model for bluefin tuna relying on the principles of Dynamic Energy Budget theory. Traditional bioenergetic models in fish research deduce energy input and utilization from observed growth and reproduction. In contrast, our model predicts growth and reproduction from food availability and temperature in the environment. We calibrated the model to emulate physiological characteristics of Pacific bluefin tuna (Thunnus orientalis, hereafter PBT), a species which has received considerable scientific attention due to its high economic value. Computer simulations suggest that (i) the main cause of different growth rates between cultivated and wild PBT is the difference in average body temperature of approximately 6.5°C, (ii) a well-fed PBT individual can spawn an average number of 9 batches per spawning season, (iii) food abundance experienced by wild PBT is rather constant and sufficiently high to provide energy for yearly reproductive cycle, (iv) energy in reserve is exceptionally small, causing the weight-length relationship of cultivated and wild PBT to be practically indistinguishable and suggesting that these fish are poorly equipped to deal with starvation, (v) accelerated growth rate of PBT larvae is connected to morphological changes prior to metamorphosis, while (vi) deceleration of growth rate in the early juvenile stage is related to efficiency of internal heat production. Based on these results, we discuss a number of physiological and ecological traits of PBT, including the reasons for high Feed Conversion Ratio recorded in bluefin tuna aquaculture. PMID:21779352

  1. Modelling retention and dispersion mechanisms of bluefin tuna eggs and larvae in the northwest Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Mariani, Patrizio; MacKenzie, Brian R.; Iudicone, Daniele; Bozec, Alexandra

    2010-07-01

    Knowledge of early life history of most fish species in the Mediterranean Sea is sparse and processes affecting their recruitment are poorly understood. This is particularly true for bluefin tuna, Thunnus thynnus, even though this species is one of the world’s most valued fish species. Here we develop, apply and validate an individually based coupled biological-physical oceanographic model of fish early life history in the Mediterranean Sea. We first validate the general structure of the coupled model with a 12-day Lagrangian drift study of anchovy ( Engraulis encrasicolus) larvae in the Catalan Sea. The model reproduced the drift and growth of anchovy larvae as they drifted along the Catalan coast and yielded similar patterns as those observed in the field. We then applied the model to investigate transport and retention processes affecting the spatial distribution of bluefin tuna eggs and larvae during 1999-2003, and we compared modelled distributions with available field data collected in 2001 and 2003. Modelled and field distributions generally coincided and were patchy at mesoscales (10s-100s km); larvae were most abundant in eddies and along frontal zones. We also identified probable locations of spawning bluefin tuna using hydrographic backtracking procedures; these locations were situated in a major salinity frontal zone and coincided with distributions of an electronically tagged bluefin tuna and commercial bluefin tuna fishing vessels. Moreover, we hypothesized that mesoscale processes are responsible for the aggregation and dispersion mechanisms in the area and showed that these processes were significantly correlated to atmospheric forcing processes over the NW Mediterranean Sea. Interannual variations in average summer air temperature can reduce the intensity of ocean mesoscale processes in the Balearic area and thus potentially affect bluefin tuna larvae. These modelling approaches can increase understanding of bluefin tuna recruitment processes and

  2. Tuna comparative physiology.

    PubMed

    Graham, Jeffrey B; Dickson, Kathryn A

    2004-11-01

    Thunniform swimming, the capacity to conserve metabolic heat in red muscle and other body regions (regional endothermy), an elevated metabolic rate and other physiological rate functions, and a frequency-modulated cardiac output distinguish tunas from most other fishes. These specializations support continuous, relatively fast swimming by tunas and minimize thermal barriers to habitat exploitation, permitting niche expansion into high latitudes and to ocean depths heretofore regarded as beyond their range.

  3. Population assessment of tropical tuna based on their associative behavior around floating objects

    PubMed Central

    Capello, M.; Deneubourg, J. L.; Robert, M.; Holland, K. N.; Schaefer, K. M.; Dagorn, L.

    2016-01-01

    Estimating the abundance of pelagic fish species is a challenging task, due to their vast and remote habitat. Despite the development of satellite, archival and acoustic tagging techniques that allow the tracking of marine animals in their natural environments, these technologies have so far been underutilized in developing abundance estimations. We developed a new method for estimating the abundance of tropical tuna that employs these technologies and exploits the aggregative behavior of tuna around floating objects (FADs). We provided estimates of abundance indices based on a simulated set of tagged fish and studied the sensitivity of our method to different association dynamics, FAD numbers, population sizes and heterogeneities of the FAD-array. Taking the case study of yellowfin tuna (Thunnus albacares) acoustically-tagged in Hawaii, we implemented our approach on field data and derived for the first time the ratio between the associated and the total population. With more extensive and long-term monitoring of FAD-associated tunas and good estimates of the numbers of fish at FADs, our method could provide fisheries-independent estimates of populations of tropical tuna. The same approach can be applied to obtain population assessments for any marine and terrestrial species that display associative behavior and from which behavioral data have been acquired using acoustic, archival or satellite tags. PMID:27808175

  4. Population assessment of tropical tuna based on their associative behavior around floating objects.

    PubMed

    Capello, M; Deneubourg, J L; Robert, M; Holland, K N; Schaefer, K M; Dagorn, L

    2016-11-03

    Estimating the abundance of pelagic fish species is a challenging task, due to their vast and remote habitat. Despite the development of satellite, archival and acoustic tagging techniques that allow the tracking of marine animals in their natural environments, these technologies have so far been underutilized in developing abundance estimations. We developed a new method for estimating the abundance of tropical tuna that employs these technologies and exploits the aggregative behavior of tuna around floating objects (FADs). We provided estimates of abundance indices based on a simulated set of tagged fish and studied the sensitivity of our method to different association dynamics, FAD numbers, population sizes and heterogeneities of the FAD-array. Taking the case study of yellowfin tuna (Thunnus albacares) acoustically-tagged in Hawaii, we implemented our approach on field data and derived for the first time the ratio between the associated and the total population. With more extensive and long-term monitoring of FAD-associated tunas and good estimates of the numbers of fish at FADs, our method could provide fisheries-independent estimates of populations of tropical tuna. The same approach can be applied to obtain population assessments for any marine and terrestrial species that display associative behavior and from which behavioral data have been acquired using acoustic, archival or satellite tags.

  5. Pacific bluefin tuna transport Fukushima-derived radionuclides from Japan to California

    PubMed Central

    Madigan, Daniel J.; Baumann, Zofia; Fisher, Nicholas S.

    2012-01-01

    The Fukushima Dai-ichi release of radionuclides into ocean waters caused significant local and global concern regarding the spread of radioactive material. We report unequivocal evidence that Pacific bluefin tuna, Thunnus orientalis, transported Fukushima-derived radionuclides across the entire North Pacific Ocean. We measured γ-emitting radionuclides in California-caught tunas and found 134Cs (4.0 ± 1.4 Bq kg−1) and elevated 137Cs (6.3 ± 1.5 Bq kg−1) in 15 Pacific bluefin tuna sampled in August 2011. We found no 134Cs and background concentrations (∼1 Bq kg−1) of 137Cs in pre-Fukushima bluefin and post-Fukushima yellowfin tunas, ruling out elevated radiocesium uptake before 2011 or in California waters post-Fukushima. These findings indicate that Pacific bluefin tuna can rapidly transport radionuclides from a point source in Japan to distant ecoregions and demonstrate the importance of migratory animals as transport vectors of radionuclides. Other large, highly migratory marine animals make extensive use of waters around Japan, and these animals may also be transport vectors of Fukushima-derived radionuclides to distant regions of the North and South Pacific Oceans. These results reveal tools to trace migration origin (using the presence of 134Cs) and potentially migration timing (using 134Cs:137Cs ratios) in highly migratory marine species in the Pacific Ocean. PMID:22645346

  6. Metal Concentrations in Two Commercial Tuna Species from an Active Volcanic Region in the Mid-Atlantic Ocean.

    PubMed

    Torres, Paulo; Rodrigues, Armindo; Soares, Lília; Garcia, Patrícia

    2016-02-01

    Concentrations of cadmium (Cd), mercury (Hg), and lead [Pb (µg g(-1) wet weight)] were determined in liver and muscle samples of 15 bigeye (Thunnus obesus) and 15 skipjack tunas (Katsuwonus pelamis) caught over an active volcanic region in the Mid-Atlantic Ocean (Azores, Portugal) and evaluated regarding consumption safety. None of the muscle samples (edible part) exceeded the European Union (EU) maximum limits (MLs) for Hg and Pb. Cd concentrations in muscle were much greater than EU MLs with 53 and 26 % of the bigeye tuna and skipjack tuna, respectively, in exceedance of the limits. Results obtained in this work, together with other studies in the same region, support the existence of an important volcanic source of Cd in waters of the Mid-Atlantic region, which should be carefully monitored given the importance of many commercial marine species for human consumption, mainly in Europe.

  7. The imprint of anthropogenic CO2 emissions on Atlantic bluefin tuna otoliths

    NASA Astrophysics Data System (ADS)

    Fraile, Igaratza; Arrizabalaga, Haritz; Groeneveld, Jeroen; Kölling, Martin; Santos, Miguel Neves; Macías, David; Addis, Piero; Dettman, David L.; Karakulak, Saadet; Deguara, Simeon; Rooker, Jay R.

    2016-06-01

    Otoliths of Atlantic bluefin tuna (Thunnus thynnus) collected from the Mediterranean Sea and North Atlantic Ocean were analyzed to evaluate changes in the seawater isotopic composition over time. We report an annual otolith δ13C record that documents the magnitude of the δ13C depletion in the Mediterranean Sea between 1989 and 2010. Atlantic bluefin tuna in our sample (n = 632) ranged from 1 to 22 years, and otolith material corresponding to the first year of life (back-calculated birth year) was used to reconstruct seawater isotopic composition. Otolith δ18O remained relatively stable between 1989 and 2010, whereas a statistically significant decrease in δ13C was detected across the time interval investigated, with a rate of decline of 0.05‰ yr- 1 (- 0.94‰ depletion throughout the recorded period). The depletion in otolith δ13C over time was associated with the oceanic uptake of anthropogenically derived CO2.

  8. Moving Cages Further Offshore: Effects on Southern Bluefin Tuna, T. maccoyii, Parasites, Health and Performance

    PubMed Central

    Kirchhoff, Nicole T.; Rough, Kirsty M.; Nowak, Barbara F.

    2011-01-01

    The effects of offshore aquaculture on SBT health (particularly parasitic infections and haematology) and performance were the main aim of this study. Two cohorts of ranched Southern Bluefin tuna (SBT) (Thunnus maccoyii) were monitored throughout the commercial season, one maintained in the traditional near shore tuna farming zone and one maintained further offshore. SBT maintained offshore had reduced mortality, increased condition index at week 6 post transfer, reduced blood fluke and sealice loads, and haematological variables such as haemoglobin or lysozyme equal to or exceeding near shore maintained fish. The offshore cohort had no Cardicola forsteri and a 5% prevalence of Caligus spp., compared to a prevalence of 85% for Cardicola forsteri and 55% prevalence for Caligus spp. near shore at 6 weeks post transfer. This study is the first of its kind to examine the effects of commercial offshore sites on farmed fish parasites, health and performance. PMID:21901129

  9. Photobacterium angustum and Photobacterium kishitanii, Psychrotrophic High-Level Histamine-Producing Bacteria Indigenous to Tuna

    PubMed Central

    McCarthy, S. A.; Dunlap, P. V.; Benner, R. A.

    2016-01-01

    Scombrotoxin fish poisoning (SFP) remains the main contributor of fish poisoning incidents in the United States, despite efforts to control its spread. Psychrotrophic histamine-producing bacteria (HPB) indigenous to scombrotoxin-forming fish may contribute to the incidence of SFP. We examined the gills, skin, and anal vents of yellowfin (n = 3), skipjack (n = 1), and albacore (n = 6) tuna for the presence of indigenous HPB. Thirteen HPB strains were isolated from the anal vent samples from albacore (n = 3) and yellowfin (n = 2) tuna. Four of these isolates were identified as Photobacterium kishitanii and nine isolates as Photobacterium angustum; these isolates produced 560 to 603 and 1,582 to 2,338 ppm histamine in marine broth containing 1% histidine (25°C for 48 h), respectively. The optimum growth temperatures and salt concentrations were 26 to 27°C and 1% salt for P. kishitanii and 30 to 32°C and 2% salt for P. angustum in Luria 70% seawater (LSW-70). The optimum activity of the HDC enzyme was at 15 to 30°C for both species. At 5°C, P. kishitanii and P. angustum had growth rates of 0.1 and 0.2 h−1, respectively, and the activities of histidine decarboxylase (HDC) enzymes were 71% and 63%, respectively. These results show that indigenous HPB in tuna are capable of growing at elevated and refrigeration temperatures. These findings demonstrate the need to examine the relationships between the rate of histamine production at refrigeration temperatures, seafood shelf life, and regulatory limits. PMID:26826233

  10. Abundance and Distribution Patterns of Thunnus albacares in Isla del Coco National Park through Predictive Habitat Suitability Models.

    PubMed

    Gonzáles-Andrés, Cristina; F M Lopes, Priscila; Cortés, Jorge; Sánchez-Lizaso, José Luis; Pennino, Maria Grazia

    2016-01-01

    Information on the distribution and habitat preferences of ecologically and commercially important species is essential for their management and protection. This is especially important as climate change, pollution, and overfishing change the structure and functioning of pelagic ecosystems. In this study, we used Bayesian hierarchical spatial-temporal models to map the Essential Fish Habitats of the Yellowfin tuna (Thunnus albacares) in the waters around Isla del Coco National Park, Pacific Costa Rica, based on independent underwater observations from 1993 to 2013. We assessed if observed changes in the distribution and abundance of this species are related with habitat characteristics, fishing intensity or more extreme climatic events, including the El Niño Southern Oscillation, and changes on the average sea surface temperature. Yellowfin tuna showed a decreasing abundance trend in the sampled period, whereas higher abundances were found in shallow and warmer waters, with high concentration of chlorophyll-a, and in surrounding seamounts. In addition, El Niño Southern Oscillation events did not seem to affect Yellowfin tuna distribution and abundance. Understanding the habitat preferences of this species, using approaches as the one developed here, may help design integrated programs for more efficient management of vulnerable species.

  11. Abundance and Distribution Patterns of Thunnus albacares in Isla del Coco National Park through Predictive Habitat Suitability Models

    PubMed Central

    Gonzáles-Andrés, Cristina; F. M. Lopes, Priscila; Cortés, Jorge; Sánchez-Lizaso, José Luis; Pennino, Maria Grazia

    2016-01-01

    Information on the distribution and habitat preferences of ecologically and commercially important species is essential for their management and protection. This is especially important as climate change, pollution, and overfishing change the structure and functioning of pelagic ecosystems. In this study, we used Bayesian hierarchical spatial-temporal models to map the Essential Fish Habitats of the Yellowfin tuna (Thunnus albacares) in the waters around Isla del Coco National Park, Pacific Costa Rica, based on independent underwater observations from 1993 to 2013. We assessed if observed changes in the distribution and abundance of this species are related with habitat characteristics, fishing intensity or more extreme climatic events, including the El Niño Southern Oscillation, and changes on the average sea surface temperature. Yellowfin tuna showed a decreasing abundance trend in the sampled period, whereas higher abundances were found in shallow and warmer waters, with high concentration of chlorophyll-a, and in surrounding seamounts. In addition, El Niño Southern Oscillation events did not seem to affect Yellowfin tuna distribution and abundance. Understanding the habitat preferences of this species, using approaches as the one developed here, may help design integrated programs for more efficient management of vulnerable species. PMID:27973538

  12. Warm fish with cold hearts: thermal plasticity of excitation–contraction coupling in bluefin tuna

    PubMed Central

    Shiels, H. A.; Di Maio, A.; Thompson, S.; Block, B. A.

    2011-01-01

    Bluefin tuna have a unique physiology. Elevated metabolic rates coupled with heat exchangers enable bluefin tunas to conserve heat in their locomotory muscle, viscera, eyes and brain, yet their hearts operate at ambient water temperature. This arrangement of a warm fish with a cold heart is unique among vertebrates and can result in a reduction in cardiac function in the cold despite the elevated metabolic demands of endothermic tissues. In this study, we used laser scanning confocal microscopy and electron microscopy to investigate how acute and chronic temperature change affects tuna cardiac function. We examined the temporal and spatial properties of the intracellular Ca2+ transient (Δ[Ca2+]i) in Pacific bluefin tuna (Thunnus orientalis) ventricular myocytes at the acclimation temperatures of 14°C and 24°C and at a common test temperature of 19°C. Acute (less than 5 min) warming and cooling accelerated and slowed the kinetics of Δ[Ca2+]i, indicating that temperature change limits cardiac myocyte performance. Importantly, we show that thermal acclimation offered partial compensation for these direct effects of temperature. Prolonged cold exposure (more than four weeks) increased the amplitude and kinetics of Δ[Ca2+]i by increasing intracellular Ca2+ cycling through the sarcoplasmic reticulum (SR). These functional findings are supported by electron microscopy, which revealed a greater volume fraction of ventricular SR in cold-acclimated tuna myocytes. The results indicate that SR function is crucial to the performance of the bluefin tuna heart in the cold. We suggest that SR Ca2+ cycling is the malleable unit of cellular Ca2+ flux, offering a mechanism for thermal plasticity in fish hearts. These findings have implications beyond endothermic fish and may help to delineate the key steps required to protect vertebrate cardiac function in the cold. PMID:20667881

  13. Why do tuna maintain elevated slow muscle temperatures? Power output of muscle isolated from endothermic and ectothermic fish.

    PubMed

    Altringham, J D; Block, B A

    1997-10-01

    It has been hypothesised that regional endothermy has evolved in the muscle of some tunas to enhance the locomotory performance of the fish by increasing muscle power output. Using the work loop technique, we have determined the relationship between cycle frequency and power output, over a range of temperatures, in isolated bundles of slow muscle fibres from the endothermic yellowfin tuna (Thunnus albacares) and its ectothermic relative the bonito (Sarda chiliensis). Power output in all preparations was highly temperature-dependent. A counter-current heat exchanger which could maintain a 10 degrees C temperature differential would typically double maximum muscle power output and the frequency at which maximum power is generated (fopt). The deep slow muscle of the tuna was able to operate at higher temperatures than slow muscle from the bonito, but was more sensitive to temperature change than more superficially located slow fibres from both tuna and bonito. This suggests that it has undergone some evolutionary specialisation for operation at higher, but relatively stable, temperatures. fopt of slow muscle was higher than the tailbeat frequency of undisturbed cruising tuna and, together with the high intrinsic power output of the slow muscle mass, suggests that cruising fish have a substantial slow muscle power reserve. This reserve should be sufficient to power significantly higher sustainable swimming speeds, presumably at lower energetic cost than if intrinsically less efficient fast fibres were recruited.

  14. Predicting Interactions between Common Dolphins and the Pole-and-Line Tuna Fishery in the Azores.

    PubMed

    Cruz, Maria João; Menezes, Gui; Machete, Miguel; Silva, Mónica A

    2016-01-01

    Common dolphins (Delphinus delphis) are responsible for the large majority of interactions with the pole-and-line tuna fishery in the Azores but the underlying drivers remain poorly understood. In this study we investigate the influence of various environmental and fisheries-related factors in promoting the interaction of common dolphins with this fishery and estimate the resultant catch losses. We analysed 15 years of fishery and cetacean interaction data (1998-2012) collected by observers placed aboard tuna fishing vessels. Dolphins interacted in less than 3% of the fishing events observed during the study period. The probability of dolphin interaction varied significantly between years with no evident trend over time. Generalized additive modeling results suggest that fishing duration, sea surface temperature and prey abundance in the region were the most important factors explaining common dolphin interaction. Dolphin interaction had no impact on the catches of albacore, skipjack and yellowfin tuna but resulted in significantly lower catches of bigeye tuna, with a predicted median annual loss of 13.5% in the number of fish captured. However, impact on bigeye catches varied considerably both by year and fishing area. Our work shows that rates of common dolphin interaction with the pole-and-line tuna fishery in the Azores are low and showed no signs of increase over the study period. Although overall economic impact was low, the interaction may lead to significant losses in some years. These findings emphasize the need for continued monitoring and for further research into the consequences and economic viability of potential mitigation measures.

  15. Predicting Interactions between Common Dolphins and the Pole-and-Line Tuna Fishery in the Azores

    PubMed Central

    Cruz, Maria João; Menezes, Gui; Machete, Miguel; Silva, Mónica A.

    2016-01-01

    Common dolphins (Delphinus delphis) are responsible for the large majority of interactions with the pole-and-line tuna fishery in the Azores but the underlying drivers remain poorly understood. In this study we investigate the influence of various environmental and fisheries-related factors in promoting the interaction of common dolphins with this fishery and estimate the resultant catch losses. We analysed 15 years of fishery and cetacean interaction data (1998–2012) collected by observers placed aboard tuna fishing vessels. Dolphins interacted in less than 3% of the fishing events observed during the study period. The probability of dolphin interaction varied significantly between years with no evident trend over time. Generalized additive modeling results suggest that fishing duration, sea surface temperature and prey abundance in the region were the most important factors explaining common dolphin interaction. Dolphin interaction had no impact on the catches of albacore, skipjack and yellowfin tuna but resulted in significantly lower catches of bigeye tuna, with a predicted median annual loss of 13.5% in the number of fish captured. However, impact on bigeye catches varied considerably both by year and fishing area. Our work shows that rates of common dolphin interaction with the pole-and-line tuna fishery in the Azores are low and showed no signs of increase over the study period. Although overall economic impact was low, the interaction may lead to significant losses in some years. These findings emphasize the need for continued monitoring and for further research into the consequences and economic viability of potential mitigation measures. PMID:27851763

  16. Gulf of Mexico Ecological Forecasting - Atlantic Bluefin Tuna Population Assessment and Management using Synthetic Aperture Radar (SAR) Data

    NASA Astrophysics Data System (ADS)

    Laygo, K.; Jones, I.; Huerta, J.; Holt, B.

    2010-12-01

    Atlantic Bluefin Tuna (Thunnus thynnus) is one of the largest vertebrates in the world and is in high demand in sushi markets. It is a highly political species and is managed internationally by the International Commission for the Conservation of Atlantic Tuna. The Gulf of Mexico and the Mediterranean Sea are the only two known spawning sites in the world. However, there is a large variance in estimates of adult Atlantic Tuna spawning. This research focuses on extending Earth science research results to existing decision-making systems, National Oceanic and Atmospheric Administration (NOAA) and the National Marine Fisheries Service (NMFS)for population assessment and management of Atlantic Bluefin Tuna. The research team is a multi-sector and multi-disciplinary team composed of government (NOAA_NMFS), academic (University of South Florida Institute for Marine Remote Sensing) and commercial (Roffer’s Ocean Fishing Forecasting Service, Inc.) institutions. Their goal is to reduce the variance in the estimates of adult Bluefin Tuna spawning stock abundance in the Gulf of Mexico (GOM). Therefore, this paper will be derived from the innovative use of several earth orbiting satellites focusing on the use of synthetic aperture radar (SAR) data to identify Sargassum, which is a floating marine algae that may be relevant to the presence of Bluefin Tuna aggregations. The SAR imagery will be examined in combination with MODIS and MERIS Chlorophyll-a products to detect fine-scale surface current shear, eddy and frontal features, as well as biological slicks due to the presence of Sargassum. In addition, wind records from NOAA buoy data will be studied to analyze wind patterns in the Gulf of Mexico. The fine-resolution, all-weather capabilities of SAR provide a valuable complement to optical/IR sensors, which are often impacted by cloud cover. This study will provide an assessment of whether or not SAR can contribute to decision support efforts relevant to commercial fisheries

  17. Spawning of Bluefin Tuna in the Black Sea: Historical Evidence, Environmental Constraints and Population Plasticity

    PubMed Central

    MacKenzie, Brian R.; Mariani, Patrizio

    2012-01-01

    The lucrative and highly migratory Atlantic bluefin tuna, Thunnus thynnus (Linnaeus 1758; Scombridae), used to be distributed widely throughout the north Atlantic Ocean, Mediterranean Sea and Black Sea. Its migrations have supported sustainable fisheries and impacted local cultures since antiquity, but its biogeographic range has contracted since the 1950s. Most recently, the species disappeared from the Black Sea in the late 1980s and has not yet recovered. Reasons for the Black Sea disappearance, and the species-wide range contraction, are unclear. However bluefin tuna formerly foraged and possibly spawned in the Black Sea. Loss of a locally-reproducing population would represent a decline in population richness, and an increase in species vulnerability to perturbations such as exploitation and environmental change. Here we identify the main genetic and phenotypic adaptations that the population must have (had) in order to reproduce successfully in the specific hydrographic (estuarine) conditions of the Black Sea. By comparing hydrographic conditions in spawning areas of the three species of bluefin tunas, and applying a mechanistic model of egg buoyancy and sinking rate, we show that reproduction in the Black Sea must have required specific adaptations of egg buoyancy, fertilisation and development for reproductive success. Such adaptations by local populations of marine fish species spawning in estuarine areas are common as is evident from a meta-analysis of egg buoyancy data from 16 species of fish. We conclude that these adaptations would have been necessary for successful local reproduction by bluefin tuna in the Black Sea, and that a locally-adapted reproducing population may have disappeared. Recovery of bluefin tuna in the Black Sea, either for spawning or foraging, will occur fastest if any remaining locally adapted individuals are allowed to survive, and by conservation and recovery of depleted Mediterranean populations which could through time re

  18. Accumulation pattern of butyltin compounds in dolphin, tuna, and shark collected from Italian coastal waters.

    PubMed

    Kannan, K; Corsolini, S; Focardi, S; Tanabe, S; Tatsukawa, R

    1996-07-01

    Tributyltin (TBT) and its breakdown products, mono-(MBT) and dibutyltin (DBT) were determined in bottlenose dolphin (Tursiops truncatus), bluefin tuna (Thunnus thynnus thynnus) and blue shark (Prionace glauca) collected from the Italian coast of the Mediterranean Sea in 1992-1993. Concentrations of total butyltin (BTs) in the liver of dolphin (1,200-2,200 ng/g wet wt) were an order of magnitude higher than in the blubber (48-320 ng/g wet wt). TBT was the predominant butyltin species in the blubber while DBT accounted for an higher proportion in the liver of dolphins. Butyltin concentrations in bluefin tuna were lower than those in dolphins, with TBT highest in the muscle and DBT in the liver. Concentrations of BTs in blue sharks were lower than those in dolphin and tuna, with kidney having the highest concentrations. TBT was the predominant form of butyltin derivatives in all the tissues of shark. Accumulation of butyltin compounds in liver/kidney seems to be associated with the presence of proteins such as glutathione.

  19. Comparative Assessment of the Reproductive Status of Female Atlantic Bluefin Tuna from the Gulf of Mexico and the Mediterranean Sea

    PubMed Central

    Knapp, Jessica M.; Aranda, Guillermo; Medina, Antonio; Lutcavage, Molly

    2014-01-01

    Despite attention focused on the population status and rebuilding trajectory of Atlantic bluefin tuna (Thunnus thynnus), the reproduction and spawning biology remains poorly understood, especially in the NW Atlantic. At present, the eastern and western spawning populations are believed to exhibit different reproductive characteristics and, consequently, stock productivity. However, our study suggests that the two spawning populations, the Gulf of Mexico and the Mediterranean Sea, could show similar reproductive features and spawning strategies. Between 2007 and 2009, gonad samples from female Atlantic bluefin tuna were collected in the northern Gulf of Mexico (n = 147) and in the western Mediterranean Sea (n = 40). The histological and stereological analysis confirmed that sampled eastern and western bluefin tuna exhibit the same spawning duration (three months) but the spawning in the Gulf of Mexico begins one month earlier than in the Mediterranean Sea. Western bluefin tuna caught in the peak of the spawning season (May) showed a similar spawning frequency (60%) to the spawning peak observed in the Mediterranean Sea (June). Fecundity for the Gulf of Mexico fish () was lower but not significantly different than for fish sampled in the Mediterranean Sea (). Our study represents the first comparative histological analysis of the eastern and western spawning stocks whose findings, combined with new determinations of size/age at maturity and possible alternative spawning areas, might suggest basic life history attributes warrant further scientific and management attention. PMID:24911973

  20. Comparative assessment of the reproductive status of female Atlantic bluefin tuna from the Gulf of Mexico and the Mediterranean Sea.

    PubMed

    Knapp, Jessica M; Aranda, Guillermo; Medina, Antonio; Lutcavage, Molly

    2014-01-01

    Despite attention focused on the population status and rebuilding trajectory of Atlantic bluefin tuna (Thunnus thynnus), the reproduction and spawning biology remains poorly understood, especially in the NW Atlantic. At present, the eastern and western spawning populations are believed to exhibit different reproductive characteristics and, consequently, stock productivity. However, our study suggests that the two spawning populations, the Gulf of Mexico and the Mediterranean Sea, could show similar reproductive features and spawning strategies. Between 2007 and 2009, gonad samples from female Atlantic bluefin tuna were collected in the northern Gulf of Mexico (n = 147) and in the western Mediterranean Sea (n = 40). The histological and stereological analysis confirmed that sampled eastern and western bluefin tuna exhibit the same spawning duration (three months) but the spawning in the Gulf of Mexico begins one month earlier than in the Mediterranean Sea. Western bluefin tuna caught in the peak of the spawning season (May) showed a similar spawning frequency (60%) to the spawning peak observed in the Mediterranean Sea (June). Fecundity for the Gulf of Mexico fish (28.14 eggs · g(-1)) was lower but not significantly different than for fish sampled in the Mediterranean Sea (45.56 eggs · g(-1)). Our study represents the first comparative histological analysis of the eastern and western spawning stocks whose findings, combined with new determinations of size/age at maturity and possible alternative spawning areas, might suggest basic life history attributes warrant further scientific and management attention.

  1. Preliminary forecasts of Pacific bigeye tuna population trends under the A2 IPCC scenario

    NASA Astrophysics Data System (ADS)

    Lehodey, P.; Senina, I.; Sibert, J.; Bopp, L.; Calmettes, B.; Hampton, J.; Murtugudde, R.

    2010-07-01

    An improved version of the spatial ecosystem and population dynamics model SEAPODYM was used to investigate the potential impacts of global warming on tuna populations. The model included an enhanced definition of habitat indices, movements, and accessibility of tuna predators to different vertically migrant and non-migrant micronekton functional groups. The simulations covered the Pacific basin (model domain) at a 2° × 2° geographic resolution. The structure of the model allows an evaluation from multiple data sources, and parameterization can be optimized by adjoint techniques and maximum likelihood using fishing data. A first such optimized parameterization was obtained for bigeye tuna ( Thunnus obesus) in the Pacific Ocean using historical catch data for the last 50 years and a hindcast from a coupled physical-biogeochemical model driven by the NCEP atmospheric reanalysis. The parameterization provided very plausible biological parameter values and a good fit to fishing data from the different fisheries, both within and outside the time period used for optimization. We then employed this model to forecast the future of bigeye tuna populations in the Pacific Ocean. The simulation was driven by the physical-biogeochemical fields predicted from a global marine biogeochemistry - climate simulation. This global simulation was performed with the IPSL climate model version 4 (IPSL-CM4) coupled to the oceanic biogeochemical model PISCES and forced by atmospheric CO 2, from historical records over 1860-2000, and under the SRES A2 IPCC scenario for the 21st century (i.e. atmospheric CO 2 concentration reaching 850 ppm in the year 2100). Potential future changes in distribution and abundance under the IPCC scenario are presented but without taking into account any fishing effort. The simulation showed an improvement in bigeye tuna spawning habitat both in subtropical latitudes and in the eastern tropical Pacific (ETP) where the surface temperature becomes optimal for

  2. Food-web inferences of stable isotope spatial patterns in copepods and yellowfin tuna in the pelagic eastern Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Olson, Robert J.; Popp, Brian N.; Graham, Brittany S.; López-Ibarra, Gladis A.; Galván-Magaña, Felipe; Lennert-Cody, Cleridy E.; Bocanegra-Castillo, Noemi; Wallsgrove, Natalie J.; Gier, Elizabeth; Alatorre-Ramírez, Vanessa; Ballance, Lisa T.; Fry, Brian

    2010-07-01

    Evaluating the impacts of climate and fishing on oceanic ecosystems requires an improved understanding of the trophodynamics of pelagic food webs. Our approach was to examine broad-scale spatial relationships among the stable N isotope values of copepods and yellowfin tuna ( Thunnus albacares), and to quantify yellowfin tuna trophic status in the food web based on stable-isotope and stomach-contents analyses. Using a generalized additive model fitted to abundance-weighted-average δ 15N values of several omnivorous copepod species, we examined isotopic spatial relationships among yellowfin tuna and copepods. We found a broad-scale, uniform gradient in δ 15N values of copepods increasing from south to north in a region encompassing the eastern Pacific warm pool and parts of several current systems. Over the same region, a similar trend was observed for the δ 15N values in the white muscle of yellowfin tuna caught by the purse-seine fishery, implying limited movement behavior. Assuming the omnivorous copepods represent a proxy for the δ 15N values at the base of the food web, the isotopic difference between these two taxa, “ ΔYFT-COP,” was interpreted as a trophic-position offset. Yellowfin tuna trophic-position estimates based on their bulk δ 15N values were not significantly different than independent estimates based on stomach contents, but are sensitive to errors in the trophic enrichment factor and the trophic position of copepods. An apparent inshore-offshore, east to west gradient in yellowfin tuna trophic position was corroborated using compound-specific isotope analysis of amino acids conducted on a subset of samples. The gradient was not explained by the distribution of yellowfin tuna of different sizes, by seasonal variability at the base of the food web, or by known ambit distances (i.e. movements). Yellowfin tuna stomach contents did not show a regular inshore-offshore gradient in trophic position during 2003-2005, but the trophic

  3. Moving with the beat: heart rate and visceral temperature of free-swimming and feeding bluefin tuna.

    PubMed

    Clark, T D; Taylor, B D; Seymour, R S; Ellis, D; Buchanan, J; Fitzgibbon, Q P; Frappell, P B

    2008-12-22

    Owing to the inherent difficulties of studying bluefin tuna, nothing is known of the cardiovascular function of free-swimming fish. Here, we surgically implanted newly designed data loggers into the visceral cavity of juvenile southern bluefin tuna (Thunnus maccoyii) to measure changes in the heart rate (fH) and visceral temperature (TV) during a two-week feeding regime in sea pens at Port Lincoln, Australia. Fish ranged in body mass from 10 to 21 kg, and water temperature remained at 18-19 degrees C. Pre-feeding fH typically ranged from 20 to 50 beats min(-1). Each feeding bout (meal sizes 2-7% of tuna body mass) was characterized by increased levels of activity and fH (up to 130 beats min(-1)), and a decrease in TV from approximately 20 to 18 degrees C as cold sardines were consumed. The feeding bout was promptly followed by a rapid increase in TV, which signified the beginning of the heat increment of feeding (HIF). The time interval between meal consumption and the completion of HIF ranged from 10 to 24 hours and was strongly correlated with ration size. Although fH generally decreased after its peak during the feeding bout, it remained elevated during the digestive period and returned to routine levels on a similar, but slightly earlier, temporal scale to TV. These data imply a large contribution of fH to the increase in circulatory oxygen transport that is required for digestion. Furthermore, these data oppose the contention that maximum fH is exceptional in bluefin tuna compared with other fishes, and so it is likely that enhanced cardiac stroke volume and blood oxygen carrying capacity are the principal factors allowing superior rates of circulatory oxygen transport in tuna.

  4. Moving with the beat: heart rate and visceral temperature of free-swimming and feeding bluefin tuna

    PubMed Central

    Clark, T.D; Taylor, B.D; Seymour, R.S; Ellis, D; Buchanan, J; Fitzgibbon, Q.P; Frappell, P.B

    2008-01-01

    Owing to the inherent difficulties of studying bluefin tuna, nothing is known of the cardiovascular function of free-swimming fish. Here, we surgically implanted newly designed data loggers into the visceral cavity of juvenile southern bluefin tuna (Thunnus maccoyii) to measure changes in the heart rate (fH) and visceral temperature (TV) during a two-week feeding regime in sea pens at Port Lincoln, Australia. Fish ranged in body mass from 10 to 21 kg, and water temperature remained at 18–19°C. Pre-feeding fH typically ranged from 20 to 50 beats min−1. Each feeding bout (meal sizes 2–7% of tuna body mass) was characterized by increased levels of activity and fH (up to 130 beats min−1), and a decrease in TV from approximately 20 to 18°C as cold sardines were consumed. The feeding bout was promptly followed by a rapid increase in TV, which signified the beginning of the heat increment of feeding (HIF). The time interval between meal consumption and the completion of HIF ranged from 10 to 24 hours and was strongly correlated with ration size. Although fH generally decreased after its peak during the feeding bout, it remained elevated during the digestive period and returned to routine levels on a similar, but slightly earlier, temporal scale to TV. These data imply a large contribution of fH to the increase in circulatory oxygen transport that is required for digestion. Furthermore, these data oppose the contention that maximum fH is exceptional in bluefin tuna compared with other fishes, and so it is likely that enhanced cardiac stroke volume and blood oxygen carrying capacity are the principal factors allowing superior rates of circulatory oxygen transport in tuna. PMID:18755679

  5. Simple measurements reveal the feeding history, the onset of reproduction, and energy conversion efficiencies in captive bluefin tuna

    NASA Astrophysics Data System (ADS)

    Jusup, Marko; Klanjšček, Tin; Matsuda, Hiroyuki

    2014-11-01

    We present a numerical approach that, in conjunction with a fully set up Dynamic Energy Budget (DEB) model, aims at consistently approximating the feeding history of cultivated fish from the commonly measured aquaculture data (body length, body mass, or the condition factor). We demonstrate the usefulness of the approach by performing validation of a DEB-based model for Pacific bluefin tuna (Thunnus orientalis) on an independent dataset and exploring the implied bioenergetics of this species in captivity. In the context of validation, the results indicate that the model successfully accounts for more than 75% of the variance in actual fish feed. At the 5% significance level, predictions do not underestimate nor overestimate observations and there is no bias. The overall model accuracy of 87.6% is satisfactory. In the context of tuna bioenergetics, we offer an explanation as to why the first reproduction in the examined case occurred only after the fish reached seven years of age, whereas it takes five years in the wild and sometimes as little as three years in captivity. Finally, we calculate energy conversion efficiencies and the supply stress throughout the entire lifetime to theoretically underpin the relatively low contribution of growth to aerobic metabolism implied by respirometry and high feed conversion ratio observed in bluefin tuna aquaculture.

  6. Individual tuna trolling strategies and transmission of fishing skills in a local community of Shimokita Peninsula.

    PubMed

    Akimichi, T

    1975-12-01

    Trolling techniques and strategies of fishermen of Oma in northern Japan to catch blue-fin tunas Thunnus thynnus are described. Usage patterns of fishing devices revealed to have ecological, psychological, and social implications. Choice of fish baits depended not only on the environmental factors relevant to the ecology of fish, but also on fishermen's skills which were different among different age groups and individuals. Younger fishermen preferred live baits to dead baits or lures whereas middle-aged or older ones chose them significantly less frequently. Moreover, the combination of a bait and a line by the latter denoted particular differences and specializations in terms of fishing strategies. Large differences in tuna landings indicating individual variations of skills were apparently related to techniques of trolling gear operation. In spite of an individual-based work. alternating work exchanging baits, and gifting were important in compensating physiological and technical handicaps through fishermen's interpersonal relationships based on genealogical, generational, and neighboring bondages. The exploitative difference between the coastal and the off-shore fishing grounds, use of baits being more varied in the latter, which were lately developed area, was also referred to as a problem of transmission in a local community of technical and mental skills.

  7. Effect of thermal acclimation on action potentials and sarcolemmal K+ channels from Pacific bluefin tuna cardiomyocytes.

    PubMed

    Galli, G L J; Lipnick, M S; Block, B A

    2009-08-01

    To sustain cardiac muscle contractility relatively independent of temperature, some fish species are capable of temporarily altering excitation-contraction coupling processes to meet the demands of their environment. The Pacific bluefin tuna, Thunnus orientalis, is a partially endothermic fish that inhabits a wide range of thermal niches. The present study examined the effects of temperature and thermal acclimation on sarcolemmal K(+) currents and their role in action potential (AP) generation in bluefin tuna cardiomyocytes. Atrial and ventricular myocytes were enzymatically isolated from cold (14 degrees C)- and warm (24 degrees C)-acclimated bluefin tuna. APs and current-voltage relations of K(+) channels were measured using the whole cell current and voltage clamp techniques, respectively. Data were collected either at the cardiomyocytes' respective acclimation temperature of 14 or 24 degrees C or at a common test temperature of 19 degrees C (to reveal the effects of acclimation). AP duration (APD) was prolonged in cold-acclimated (CA) cardiomyocytes tested at 14 degrees C compared with 19 degrees C and in warm-acclimated (WA) cardiomyocytes tested at 19 degrees C compared with 24 degrees C. This effect was mirrored by a decrease in the density of the delayed-rectifier current (I(Kr)), whereas the density of the background inward-rectifier current (I(K1)) was unchanged. When CA and WA cardiomyocytes were tested at a common temperature of 19 degrees C, no significant effects of temperature acclimation on AP shape or duration were observed, whereas I(Kr) density was markedly increased in CA cardiomyocytes. I(K1) density was unaffected in CA ventricular myocytes but was significantly reduced in CA atrial myocytes, resulting in a depolarization of atrial resting membrane potential. Our results indicate the bluefin AP is relatively short compared with other teleosts, which may allow the bluefin heart to function at cold temperatures without the necessity for thermal

  8. 76 FR 39019 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Quotas and Atlantic Tuna Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-05

    ... the Atlantic tunas possession-at-sea and landing regulations to allow removal of Atlantic tunas tail lobes; and clarifying the transfer-at-sea regulations for Atlantic tunas. This action is necessary to... consideration of overharvest/underharvest from the previous fishing year and any accounting for estimated...

  9. 78 FR 70002 - International Fisheries; Pacific Tuna Fisheries; 2013 Bigeye Tuna Longline Fishery Closure in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-22

    ...; Pacific Tuna Fisheries; 2013 Bigeye Tuna Longline Fishery Closure in the Eastern Pacific Ocean; Correction... in the Eastern Pacific Ocean for the remainder of 2013. DATES: Effective November 11, 2013, through.... SUPPLEMENTARY INFORMATION: NMFS announced that the bigeye tuna longline fishery in the Eastern Pacific...

  10. Determination and quantification of PCBs, POCs and PAHs in Thunnus thynnus from the Straits of Messina (Italy)

    PubMed Central

    Saija, Emanuele; Mangano, Valentina; Casale, Katia Ermina; La Torre, Giovanna Loredana; Dugo, Giacomo; Salvo, Andrea

    2016-01-01

    This data set is composed to assess the accumulation of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs) dioxin like (DL) and not dioxin like (NDL), organochlorine pesticides (POCs) and polycyclic aromatic hydrocarbons (PAHs) in Thunnus thynnus and to elucidate the suitability of this species as a bioindicator for monitoring contaminations of these compounds in the marine ecosystems of the Straits of Messina. This investigation was conducted on liver samples of 14 T. thynnus collected during April 2015. Quantitative determination of PCBs (DL and NDL), POCs and PAHs in the examined samples has been carried out by HRGC-MS/MS. Among the PCBs, high prevalence of DL was found while, generally, the values detected for PCBs–NDL were lower than the legal limits. Tuna samples analyzed for PAHs residues revealed that all the samples were contaminated with acenaphthalene, fluorene, phenanthrene and anthracene. Moreover, generally the residual levels of DDT and DDT metabolites were low. The total content of PCB–DL, in almost all the samples, showed higher concentration than the legal limit. PMID:26933670

  11. Thawing of Frozen Tuna Meat

    NASA Astrophysics Data System (ADS)

    Tanaka, Takeo; Nishiwaki, Kôji; Kakuda, Kitonari; Tomimatsu, Takao

    Frozen southern bluefin tuna meat discolors easily and sometimes contracts when thawed caused by thaw rigor. These phenomenon often become problematic in the transaction or handling of this kind of frozen tuna. Frozen meat blocks of southern Bluefin tuna were thawed separately by air thawing, running water thawing and microwave thawing. Changes occurring during thawing were checked for meat color by met-myoglobin ratio determination and for contract by microscopic observation. Results are as follows : (1) Discoloration scarcely occurred in the process of running water thawing (at 10°C for 50 min, or at 0°C for 6 hr). (2) No contraction was observed during thawing with running water described above and air thawing (at 18-20°C for 6 hr). (3) Discoloration and contraction seemed to be minimized, as to latently contractile blocks, when meat temperature passed through rapidly between -10°C and -5°C, and slowly (for 5-6 hr) between -5°C and -1°C. When the block was originally not contractile, discloration was minimized by rising meat temperature rapidly from -10°C to -l°C.

  12. Space Technology For Tuna Boats

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Freshly-caught tuna is stored below decks in wells cooled to about zero degrees by brine circulated through a refrigerating system. The wells formerly were insulated by cork or fiberglass, but both materials were subject to deterioration; cork, for instance, needs replacement every three years. The Campbell Machine Division of Campbell Industries, San Diego, which manufactures and repairs large boats for the commercial fishing industry, was looking for a better way to insulate tuna storage wells. Learning of the Rockwell technique, Campbell contracted for a test installation on one boat, then bought its own equipment and adopted the spray-foam procedure for their boats. The foam hardens after application. It not only is a superior insulator, it also is considerably lighter and easier to apply. Fishing industry spokesmen say that foam insulation is far more reliable, efficient and economical than prior techniques. More than 40 foam-insulated tuna boats, ranging in cost from $1 million to $4 million, have been built and sold. Principal customers are Ralston Purina's Van Camp Seafood Division and Star-Kist Inc.

  13. 50 CFR 600.525 - Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast. 600.525 Section 600.525 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE...

  14. 50 CFR 600.525 - Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Applicability of subpart F to Canadian Albacore Fishing Vessels off the West Coast. 600.525 Section 600.525 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE...

  15. Seafloor bathymetry and gravity from the ALBACORE marine seismic experiment offshore southern California

    NASA Astrophysics Data System (ADS)

    Shintaku, N.; Weeraratne, D. S.; Kohler, M. D.

    2010-12-01

    Although the North America side of the plate boundary surrounding the southern California San Andreas fault region is well studied and instrumented, the Pacific side of this active tectonic boundary is poorly understood. In order to better understand this complex plate boundary offshore, its microplate structures, deformation, and the California Borderland formation, we have recently conducted the first stage of a marine seismic experiment (ALBACORE - Asthenospheric and Lithospheric Broadband Architecture from the California Offshore Region Experiment) deploying 34 ocean bottom seismometers offshore southern California in August 2010. We present preliminary data consisting of seafloor bathymetry and free air gravity collected from this experiment. We present high-resolution maps of bathymetry and gravity from the ALBACORE experiment compiled with previous ship track data obtained from the NGDC (National Geophysical Data Center) and the USGS. We use gravity data from Smith and Sandwell and study correlations with ship track bathymetry data for the features described below. We observe new seafloor geomorphological features far offshore and within the Borderland. Steep canyon walls which line the edges of the Murray fracture zone with possible volcanic flows along the canyon floor were mapped by multibeam bathymetry for the first time. Deep crevices juxtaposed with high edifices of intensely deformed plateaus indicate high strain deformation along the arcuate boundary of the Arguello microplate. Small volcanic seamounts are mapped which straddle the Ferrelo fault (Outer Borderland) and San Pedro fault (Inner Borderland), and appear to exhibit fracture and fault displacement of a portion of the volcanic centers in a left-lateral sense. A large landslide is also imaged extending approximately 6 miles in length and 3 miles in width in the Santa Cruz basin directly south of Santa Rosa Island. Deformation associated with capture of Arguello and Patton microplates by the

  16. Trade-based estimation of bluefin tuna catches in the Eastern Atlantic and Mediterranean, 2005-2011.

    PubMed

    Gagern, Antonius; van den Bergh, Jeroen; Sumaila, Ussif Rashid

    2013-01-01

    The Eastern Atlantic and Mediterranean stock of Bluefin tuna Thunnus thynnus (BFTE) has long been considered overfished and at risk of collapse. Although ICCAT quotas for this stock have decreased considerably over the past years, uncertainty exists about the degree of catch beyond this quota. The extent of such catch is an important piece of information in stock assessment models as well as being an indicator of the effectiveness of fisheries management. We present a model using Bluefin tuna trade data to infer actual catches. Basing our calculations on 25 countries involved in BFTE trade, we estimate that between 2005 and 2011, allowable quotas were exceeded by 44 percent. This gap between catch and quotas has slightly increased over past years, leading to estimated excess catches of 57 percent for the period between 2008 and 2011. To improve assessments, preparation and design of BFTE management, we suggest that the estimated total removals reported in this paper be included in stock assessment models for BFTE. An implication of our findings is that ICCAT member states should take stronger measures to monitor and enforce compliance with quotas.

  17. Quantifying overlap between the Deepwater Horizon oil spill and predicted bluefin tuna spawning habitat in the Gulf of Mexico

    PubMed Central

    Hazen, Elliott L.; Carlisle, Aaron B.; Wilson, Steven G.; Ganong, James E.; Castleton, Michael R.; Schallert, Robert J.; Stokesbury, Michael J. W.; Bograd, Steven J.; Block, Barbara A.

    2016-01-01

    Atlantic bluefin tuna (Thunnus thynnus) are distributed throughout the North Atlantic and are both economically valuable and heavily exploited. The fishery is currently managed as two spawning populations, with the GOM population being severely depleted for over 20 years. In April-August of 2010, the Deepwater Horizon oil spill released approximately 4 million barrels of oil into the GOM, with severe ecosystem and economic impacts. Acute oil exposure results in mortality of bluefin eggs and larvae, while chronic effects on spawning adults are less well understood. Here we used 16 years of electronic tagging data for 66 bluefin tuna to identify spawning events, to quantify habitat preferences, and to predict habitat use and oil exposure within Gulf of Mexico spawning grounds. More than 54,000 km2 (5%) of predicted spawning habitat within the US EEZ was oiled during the week of peak oil dispersal, with potentially lethal effects on eggs and larvae. Although the oil spill overlapped with a relatively small portion of predicted spawning habitat, the cumulative impact from oil, ocean warming and bycatch mortality on GOM spawning grounds may result in significant effects for a population that shows little evidence of rebuilding. PMID:27654709

  18. Quantifying overlap between the Deepwater Horizon oil spill and predicted bluefin tuna spawning habitat in the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Hazen, Elliott L.; Carlisle, Aaron B.; Wilson, Steven G.; Ganong, James E.; Castleton, Michael R.; Schallert, Robert J.; Stokesbury, Michael J. W.; Bograd, Steven J.; Block, Barbara A.

    2016-09-01

    Atlantic bluefin tuna (Thunnus thynnus) are distributed throughout the North Atlantic and are both economically valuable and heavily exploited. The fishery is currently managed as two spawning populations, with the GOM population being severely depleted for over 20 years. In April-August of 2010, the Deepwater Horizon oil spill released approximately 4 million barrels of oil into the GOM, with severe ecosystem and economic impacts. Acute oil exposure results in mortality of bluefin eggs and larvae, while chronic effects on spawning adults are less well understood. Here we used 16 years of electronic tagging data for 66 bluefin tuna to identify spawning events, to quantify habitat preferences, and to predict habitat use and oil exposure within Gulf of Mexico spawning grounds. More than 54,000 km2 (5%) of predicted spawning habitat within the US EEZ was oiled during the week of peak oil dispersal, with potentially lethal effects on eggs and larvae. Although the oil spill overlapped with a relatively small portion of predicted spawning habitat, the cumulative impact from oil, ocean warming and bycatch mortality on GOM spawning grounds may result in significant effects for a population that shows little evidence of rebuilding.

  19. Trade-Based Estimation of Bluefin Tuna Catches in the Eastern Atlantic and Mediterranean, 2005–2011

    PubMed Central

    Gagern, Antonius; van den Bergh, Jeroen; Sumaila, Ussif Rashid

    2013-01-01

    The Eastern Atlantic and Mediterranean stock of Bluefin tuna Thunnus thynnus (BFTE) has long been considered overfished and at risk of collapse. Although ICCAT quotas for this stock have decreased considerably over the past years, uncertainty exists about the degree of catch beyond this quota. The extent of such catch is an important piece of information in stock assessment models as well as being an indicator of the effectiveness of fisheries management. We present a model using Bluefin tuna trade data to infer actual catches. Basing our calculations on 25 countries involved in BFTE trade, we estimate that between 2005 and 2011, allowable quotas were exceeded by 44 percent. This gap between catch and quotas has slightly increased over past years, leading to estimated excess catches of 57 percent for the period between 2008 and 2011. To improve assessments, preparation and design of BFTE management, we suggest that the estimated total removals reported in this paper be included in stock assessment models for BFTE. An implication of our findings is that ICCAT member states should take stronger measures to monitor and enforce compliance with quotas. PMID:23922870

  20. Quantifying overlap between the Deepwater Horizon oil spill and predicted bluefin tuna spawning habitat in the Gulf of Mexico.

    PubMed

    Hazen, Elliott L; Carlisle, Aaron B; Wilson, Steven G; Ganong, James E; Castleton, Michael R; Schallert, Robert J; Stokesbury, Michael J W; Bograd, Steven J; Block, Barbara A

    2016-09-22

    Atlantic bluefin tuna (Thunnus thynnus) are distributed throughout the North Atlantic and are both economically valuable and heavily exploited. The fishery is currently managed as two spawning populations, with the GOM population being severely depleted for over 20 years. In April-August of 2010, the Deepwater Horizon oil spill released approximately 4 million barrels of oil into the GOM, with severe ecosystem and economic impacts. Acute oil exposure results in mortality of bluefin eggs and larvae, while chronic effects on spawning adults are less well understood. Here we used 16 years of electronic tagging data for 66 bluefin tuna to identify spawning events, to quantify habitat preferences, and to predict habitat use and oil exposure within Gulf of Mexico spawning grounds. More than 54,000 km(2) (5%) of predicted spawning habitat within the US EEZ was oiled during the week of peak oil dispersal, with potentially lethal effects on eggs and larvae. Although the oil spill overlapped with a relatively small portion of predicted spawning habitat, the cumulative impact from oil, ocean warming and bycatch mortality on GOM spawning grounds may result in significant effects for a population that shows little evidence of rebuilding.

  1. Atlantic Bluefin Tuna: A Novel Multistock Spatial Model for Assessing Population Biomass

    PubMed Central

    Taylor, Nathan G.; McAllister, Murdoch K.; Lawson, Gareth L.; Carruthers, Tom; Block, Barbara A.

    2011-01-01

    Atlantic bluefin tuna (Thunnus thynnus) is considered to be overfished, but the status of its populations has been debated, partly because of uncertainties regarding the effects of mixing on fishing grounds. A better understanding of spatial structure and mixing may help fisheries managers to successfully rebuild populations to sustainable levels while maximizing catches. We formulate a new seasonally and spatially explicit fisheries model that is fitted to conventional and electronic tag data, historic catch-at-age reconstructions, and otolith microchemistry stock-composition data to improve the capacity to assess past, current, and future population sizes of Atlantic bluefin tuna. We apply the model to estimate spatial and temporal mixing of the eastern (Mediterranean) and western (Gulf of Mexico) populations, and to reconstruct abundances from 1950 to 2008. We show that western and eastern populations have been reduced to 17% and 33%, respectively, of 1950 spawning stock biomass levels. Overfishing to below the biomass that produces maximum sustainable yield occurred in the 1960s and the late 1990s for western and eastern populations, respectively. The model predicts that mixing depends on season, ontogeny, and location, and is highest in the western Atlantic. Assuming that future catches are zero, western and eastern populations are predicted to recover to levels at maximum sustainable yield by 2025 and 2015, respectively. However, the western population will not recover with catches of 1750 and 12,900 tonnes (the “rebuilding quotas”) in the western and eastern Atlantic, respectively, with or without closures in the Gulf of Mexico. If future catches are double the rebuilding quotas, then rebuilding of both populations will be compromised. If fishing were to continue in the eastern Atlantic at the unregulated levels of 2007, both stocks would continue to decline. Since populations mix on North Atlantic foraging grounds, successful rebuilding policies will

  2. [Fatty acid composition and cholesterol content in naturally canned jurel, sardine, salmon, and tuna].

    PubMed

    Romero, N; Robert, P; Masson, L; Luck, C; Buschmann, L

    1996-03-01

    To obtain more information about fatty acid profile and cholesterol content of fat extracted from canned fish in brine habitually consumed in Chile, four different species Jurel (Trachurus murphyi), Sardine (Sardinops sagax), Salmon (Oncorhynchus kisutch) and Tuna (Thunnus alalunga) were analyzed. The GLC of fatty acid methyl esters showed that the main group of fatty acids belongs to polyunsaturated, being omega-3 family the more important. The principal representants were eicosapentaenoic (EPA) and docosahexaenoic acids (DHA), with percentages between 5%-11% and 12%-22% respectively. Omega-6 family was represented mainly by arachidonic acid (AA) with percentages between 2%-4%. Cholesterol content was similar to the values found in other animal origen meats. The figures were between 41-86 mg of cholesterol per 100 g of edible product, Tuna in brine, was the product with the lowest content of cholesterol. The calculated amount of EPA, DHA and total omega-3 fatty acids indicated values between 95-604, 390-1163 and 609-2775 mg respectively per 100 g of edible product. Due these results is important to emphasize the consumption of this type of canned fish in brine, that they really represent a good dietary source of mainly polyunsaturated omega-3 fatty acids. The international recommendations indicate to increase the consumption of fish, due the beneficial effects described in relation with cardiovascular disease, which is the mean cause of death in Chile, country with a wide variety of marine origen foods, but with a contradictory answer about its consumption which is not incorporated in the current diet.

  3. Atlantic bluefin tuna: a novel multistock spatial model for assessing population biomass.

    PubMed

    Taylor, Nathan G; McAllister, Murdoch K; Lawson, Gareth L; Carruthers, Tom; Block, Barbara A

    2011-01-01

    Atlantic bluefin tuna (Thunnus thynnus) is considered to be overfished, but the status of its populations has been debated, partly because of uncertainties regarding the effects of mixing on fishing grounds. A better understanding of spatial structure and mixing may help fisheries managers to successfully rebuild populations to sustainable levels while maximizing catches. We formulate a new seasonally and spatially explicit fisheries model that is fitted to conventional and electronic tag data, historic catch-at-age reconstructions, and otolith microchemistry stock-composition data to improve the capacity to assess past, current, and future population sizes of Atlantic bluefin tuna. We apply the model to estimate spatial and temporal mixing of the eastern (Mediterranean) and western (Gulf of Mexico) populations, and to reconstruct abundances from 1950 to 2008. We show that western and eastern populations have been reduced to 17% and 33%, respectively, of 1950 spawning stock biomass levels. Overfishing to below the biomass that produces maximum sustainable yield occurred in the 1960s and the late 1990s for western and eastern populations, respectively. The model predicts that mixing depends on season, ontogeny, and location, and is highest in the western Atlantic. Assuming that future catches are zero, western and eastern populations are predicted to recover to levels at maximum sustainable yield by 2025 and 2015, respectively. However, the western population will not recover with catches of 1750 and 12,900 tonnes (the "rebuilding quotas") in the western and eastern Atlantic, respectively, with or without closures in the Gulf of Mexico. If future catches are double the rebuilding quotas, then rebuilding of both populations will be compromised. If fishing were to continue in the eastern Atlantic at the unregulated levels of 2007, both stocks would continue to decline. Since populations mix on North Atlantic foraging grounds, successful rebuilding policies will

  4. Climate effects on historic bluefin tuna captures in the Gibraltar Strait and Western Mediterranean

    NASA Astrophysics Data System (ADS)

    Ganzedo, Unai; Polanco-Martínez, Josué M.; Caballero-Alfonso, Ángela M.; Faria, Sérgio H.; Li, Jianke; Castro-Hernández, José J.

    2016-06-01

    Historical capture records of bluefin tuna (Thunnus thynnus; BFT hereafter) from the Gibraltar Strait and Western Mediterranean show pronounced short- and long-term fluctuations. Some of these fluctuations are believed to be associated with biological and ecological process, as well as distinct climate factors. For the period of study (1700-1936) of this work, we found a long-term increasing trend in the BFT captures and in the climate variables. After applying a statistical time series analysis of relevant climate variables and long-term tuna capture records, it is highlighted the role played by sea-surface temperature (SST) on bluefin population variations. The most relevant result of this study is the strong correlation found between the total solar irradiance (TSI) - an external component of the climate system - and bluefin captures. The solar irradiance could have affected storminess during the period under study, mainly during the time interval 1700-1810. We suggest physico-biological mechanisms that explain the BFT catch fluctuations in two consecutive time intervals. In the first period, from 1700 to 1810, this mechanism could be high storm and wind activity, which would have made the BFT fisheries activities more difficult by reducing their efficacy. In contrast, during the interval from 1810 to 1907, the effects of wind and storms could be on spawning behaviour and larval ecology, and hence on year class strength, rather than on fish or fisherman's behaviour. These findings open up a range of new lines of enquiry that are relevant for both, fisheries and climate change research.

  5. Swimming performance studies on the eastern Pacific bonito Sarda chiliensis, a close relative of the tunas (family Scombridae) I. Energetics.

    PubMed

    Sepulveda, C A; Dickson, K A; Graham, J B

    2003-08-01

    A large swim tunnel respirometer was used to quantify the swimming energetics of the eastern Pacific bonito Sarda chiliensis (tribe Sardini) (45-50 cm fork length, FL) at speeds between 50 and 120 cm s(-1) and at 18+/-2 degrees C. The bonito rate of oxygen uptake ((O(2)))-speed function is U-shaped with a minimum (O(2)) at 60 cm s(-1), an exponential increase in (O(2)) with increased speed, and an elevated increase in (O(2)) at 50 cm s(-1) where bonito swimming is unstable. The onset of unstable swimming occurs at speeds predicted by calculation of the minimum speed for bonito hydrostatic equilibrium (1.2 FL s(-1)). The optimum swimming speed (U(opt)) for the bonito at 18+/-2 degrees C is approximately 70 cm s(-1) (1.4 FL s(-1)) and the gross cost of transport at U(opt) is 0.27 J N(-1) m(-1). The mean standard metabolic rate (SMR), determined by extrapolating swimming (O(2)) to zero speed, is 107+/-22 mg O(2) kg(-1) h(-1). Plasma lactate determinations at different phases of the experiment showed that capture and handling increased anaerobic metabolism, but plasma lactate concentration returned to pre-experiment levels over the course of the swimming tests. When adjustments are made for differences in temperature, bonito net swimming costs are similar to those of similar-sized yellowfin tuna Thunnus albacares (tribe Thunnini), but the bonito has a significantly lower SMR. Because bonitos are the sister group to tunas, this finding suggests that the elevated SMR of the tunas is an autapomorphic trait of the Thunnini.

  6. Co-Occurrence and Habitat Use of Fin Whales, Striped Dolphins and Atlantic Bluefin Tuna in the Northwestern Mediterranean Sea.

    PubMed

    Bauer, Robert Klaus; Fromentin, Jean-Marc; Demarcq, Hervé; Brisset, Blandine; Bonhommeau, Sylvain

    2015-01-01

    Different dolphin and tuna species have frequently been reported to aggregate in areas of high frontal activity, sometimes developing close multi-species associations to increase feeding success. Aerial surveys are a common tool to monitor the density and abundance of marine mammals, and have recently become a focus in the search for methods to provide fisheries-independent abundance indicators for tuna stock assessment. In this study, we present first density estimates corrected for availability bias of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Golf of Lions (GoL), compared with uncorrected estimates of Atlantic bluefin tuna (ABFT; Thunnus thynnus) densities from 8 years of line transect aerial surveys. The raw sighting data were further used to analyze patterns of spatial co-occurrence and density of these three top marine predators in this important feeding ground in the Northwestern Mediterranean Sea. These patterns were investigated regarding known species-specific feeding preferences and environmental characteristics (i. e. mesoscale activity) of the survey zone. ABFT was by far the most abundant species during the surveys in terms of schools and individuals, followed by striped dolphins and fin whales. However, when accounted for availability bias, schools of dolphins and fin whales were of equal density. Direct interactions of the species appeared to be the exception, but results indicate that densities, presence and core sighting locations of striped dolphins and ABFT were correlated. Core sighting areas of these species were located close to an area of high mesoscale activity (oceanic fronts and eddies). Fin whales did not show such a correlation. The results further highlight the feasibility to coordinate research efforts to explore the behaviour and abundance of the investigated species, as demanded by the Marine Strategy Framework Directive (MSFD).

  7. Co-Occurrence and Habitat Use of Fin Whales, Striped Dolphins and Atlantic Bluefin Tuna in the Northwestern Mediterranean Sea

    PubMed Central

    Bauer, Robert Klaus; Demarcq, Hervé; Brisset, Blandine

    2015-01-01

    Different dolphin and tuna species have frequently been reported to aggregate in areas of high frontal activity, sometimes developing close multi-species associations to increase feeding success. Aerial surveys are a common tool to monitor the density and abundance of marine mammals, and have recently become a focus in the search for methods to provide fisheries-independent abundance indicators for tuna stock assessment. In this study, we present first density estimates corrected for availability bias of fin whales (Balaenoptera physalus) and striped dolphins (Stenella coeruleoalba) from the Golf of Lions (GoL), compared with uncorrected estimates of Atlantic bluefin tuna (ABFT; Thunnus thynnus) densities from 8 years of line transect aerial surveys. The raw sighting data were further used to analyze patterns of spatial co-occurrence and density of these three top marine predators in this important feeding ground in the Northwestern Mediterranean Sea. These patterns were investigated regarding known species-specific feeding preferences and environmental characteristics (i. e. mesoscale activity) of the survey zone. ABFT was by far the most abundant species during the surveys in terms of schools and individuals, followed by striped dolphins and fin whales. However, when accounted for availability bias, schools of dolphins and fin whales were of equal density. Direct interactions of the species appeared to be the exception, but results indicate that densities, presence and core sighting locations of striped dolphins and ABFT were correlated. Core sighting areas of these species were located close to an area of high mesoscale activity (oceanic fronts and eddies). Fin whales did not show such a correlation. The results further highlight the feasibility to coordinate research efforts to explore the behaviour and abundance of the investigated species, as demanded by the Marine Strategy Framework Directive (MSFD). PMID:26458254

  8. 78 FR 65887 - International Fisheries; Pacific Tuna Fisheries; 2013 Bigeye Tuna Longline Fishery Closure in the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-04

    ... National Oceanic and Atmospheric Administration 50 CFR Part 300 RIN 0648-XC922 International Fisheries; Pacific Tuna Fisheries; 2013 Bigeye Tuna Longline Fishery Closure in the Eastern Pacific Ocean AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA),...

  9. Estimating diets of pre-spawning Atlantic bluefin tuna from stomach content and stable isotope analyses

    NASA Astrophysics Data System (ADS)

    Varela, José L.; Rodríguez-Marín, Enrique; Medina, Antonio

    2013-02-01

    Stomach content analysis (SCA) and stable isotope analysis (SIA) coupled with isotopic mixing model analysis were used to estimate diet composition of pre-spawning Atlantic bluefin tuna (ABFT), Thunnus thynnus, caught by trap in the Strait of Gibraltar area. SCA provided poor information on diet as most of the stomachs appeared empty or contained only hard remains. Mixing model diet compositions estimated from muscle tissue SIA data did not show clear inter-annual variations and suggested that ABFT fed on prey that occupy high and intermediate level positions of the food web. Otherwise, diet compositions estimated from liver tissue SIA showed greater inter-annual variations and appeared to indicate that ABFT fed on prey located at lower trophic levels. The different dietary compositions inferred from muscle and liver samples were most probably due to the different turnover rates of these organs, which would provide trophic information at two distinct time scales. Our findings suggest that a combination of SCA and SIA is more suitable than using SCA alone to determine temporal and regional variations in ABFT diet composition.

  10. Reconstructing transoceanic migration patterns of Pacific bluefin tuna using a chemical tracer toolbox.

    PubMed

    Madigan, Daniel J; Baumann, Zofia; Carlisle, Aaron B; Hoen, Danielle K; Popp, Brian N; Dewar, Heidi; Snodgrass, Owyn E; Block, Barbara A; Fisher, Nicholas S

    2014-06-01

    Large pelagic predators play important roles in oceanic ecosystems, and may migrate vast distances to utilize resources in different marine ecoregions. Understanding movement patterns of migratory marine animals is critical for effective management, but often challenging, due to the cryptic habitat of pelagic migrators and the difficulty of assessing past movements. Chemical tracers can partially circumvent these challenges by reconstructing recent migration patterns. Pacific bluefin tuna (Thunnus orientalis; PBFT) inhabit the western and eastern Pacific Ocean, and are in steep decline due to overfishing. Understanding age-specific eastward transpacific migration patterns can improve management practices, but these migratory dynamics remain largely unquantified. Here, we combine a Fukushima-derived radiotracer (134Cs) with bulk tissue and amino acid stable isotope analyses of PBFT to distinguish recent migrants from residents of the eastern Pacific Ocean. The proportion of recent migrants to residents decreased in older year classes, though the proportion of older PBFT that recently migrated across the Pacific was greater than previous estimates. This novel toolbox of biogeochemical tracers can be applied to any species that crosses the North Pacific Ocean.

  11. Histamine development and bacterial diversity in microbially-challenged tonggol (Thunnus tonggol) under temperature abuse during canning manufacture.

    PubMed

    Hongpattarakere, Tipparat; Buntin, Nirunya; Nuylert, Aem

    2016-01-01

    Histamine formation and bacteriological changes caused by temperature abuse commonly occurring in the manufacturing process of standard canned tuna was assessed in microbiologically challenged tonggol (Thunnus tonggol). The in situ challenge was performed by water-soaking at 26-28 °C for 7 h to ensure the multiplication and active phase of fish microflora. Right after pre-cooking to back-bone temperature (BBT) of 50-52 °C, histamine dropped to 5.17 ± 2.71 ppm, and slowly reached 6.84 ± 1.69 ppm at 16 h abuse. On the contrary, histamine was reduced to 2.87 ± 1.23 ppm and eventually reached 5.01 ± 1.32 ppm at 24 h abuse in the pre-cooked fish previously frozen. The numbers of total aerobic bacteria, Enterobactericeae, psychrotroph, histamine forming bacteria (HFB) and diversity of fish microflora were revealed by cultural and nested PCR-Denaturing Gradient Gel Electrophoresis (PCR-DGGE) techniques. Interestingly, frozen storage effectively halted histamine formation in raw fish throughout 16 h abuse despite the presence of HFB. These included the prolific strains of Morganella morganii, Proteus penneri, Proteus mirabilin, Citrobacter spp. The nested PCR-DGGE profile confirmed the presence of M. morganii and Citrobacter spp. in raw fish. These prolific strains were hardly observed in the precooked fish previously frozen. Frozen storage did not only promote even histamine distribution throughout fish muscle but also enhanced histamine loss during thawing and pre-cooking. Therefore, pre-cooking and frozen storage were proven to be the effective combined hurdles not only to reduce but also prolong histamine formation of the challenged toggol throughout 24 h of temperature abuse during canning process.

  12. Environmental forcing and the larval fish community associated to the Atlantic bluefin tuna spawning habitat of the Balearic region (Western Mediterranean), in early summer 2005

    NASA Astrophysics Data System (ADS)

    Rodriguez, J. M.; Alvarez, I.; Lopez-Jurado, J. L.; Garcia, A.; Balbin, R.; Alvarez-Berastegui, D.; Torres, A. P.; Alemany, F.

    2013-07-01

    The Balearic region is a highly dynamic area located in the Western Mediterranean, straddling the transition between the Algerian and Provencal basins and constitutes one of the main spawning grounds for the large, migratory Atlantic bluefin (Thunnus thynnus) and other medium and small tuna species (Thunnus alalunga, Auxis rochei, Euthynnus alleteratus and Katsuwonus pelamis). In summer, despite been considered an oligotrophic region as the whole Mediterranean Sea, it harbors a relatively abundant and diverse larval fish community (LFC). In this study, we analyze the composition, abundance and the influence of abiotic and biotic factors on the horizontal structure of the LFC in the Balearic region, in early summer 2005, during the spawning season of Atlantic bluefin tuna. Hydrographically, 2005 was an unusual year with a summer situation of relatively lack of mesoscale features, weak surface currents and a general situation of high stability. A total of 128 taxa of fish larvae, belonging to 52 families, were identified. The average abundance was 1770 larvae 1000 m-3. Multivariate statistical analysis revealed LFC to have a strong horizontal structure. Cluster analysis and non-metric multidimensional scaling ordination identified two larval fish assemblages. These assemblages were mainly delineated by depth and, therefore, by the spawning location of adult fish. Our results also suggest that anticyclonic eddy boundaries constitute favourable habitats for fish larvae. Also, the scenario of higher than unusual hydrographic stability found during the cruise would be responsible for the relatively lack of mesoscale features and, consequently, for the lack of influence of these features on the horizontal distribution of fish larvae and on the horizontal structure of the LFC.

  13. Global integration of European tuna markets

    NASA Astrophysics Data System (ADS)

    Jiménez-Toribio, Ramòn; Guillotreau, Patrice; Mongruel, Rémi

    2010-07-01

    This paper evaluates the degree of integration between the world market and the major European marketplaces of frozen and canned tuna through both vertical and horizontal price relationships. Spatial linkages are investigated horizontally in order to estimate the connection between the European market and the world-wide market on the primary stage of the value chain. One of the key results is the high level of market integration at the ex-vessel stage, and the price leadership of yellowfin tuna over skipjack tuna. The same approach is applied at the ex-factory level. Basically, the European market for final goods appears to be segmented between the Northern countries consuming low-priced canned skipjack tuna imported from Asia (mainly Thailand) and the Southern countries (Italy, Spain) processing and importing yellowfin-based products sold at higher prices. France appears to be an intermediate market where both products are consumed. The former market is found to be well integrated to the world market and can be considered to be competitive, but there is a suspicion of market power being exercised on the latter. Price relationships are therefore tested vertically between the price of frozen tuna paid by the canneries and the price of canned fish in both Italy and France. The two species show an opposite pattern in prices transmission along the value chain: price changes along the chain are far better transmitted for the “global” skipjack tuna than for the more “European” yellowfin tuna. The results are discussed, along with their implications for the fishing industry.

  14. 77 FR 25732 - Tuna-Tariff-Rate Quota; the Tariff-Rate Quota for Calendar Year 2012 Tuna Classifiable Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-01

    ... SECURITY U.S. Customs and Border Protection Tuna--Tariff-Rate Quota; the Tariff-Rate Quota for Calendar.... ACTION: Announcement of the quota quantity of tuna in airtight containers for Calendar Year 2012..., 2012, a document concerning tariff rates for tuna in airtight containers for Calendar Year...

  15. 77 FR 22796 - Tuna-Tariff-Rate Quota; the Tariff-Rate Quota for Calendar Year 2012 Tuna Classifiable Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... Year 2012 Tuna Classifiable Under Subheading 1604.14.22, Harmonized Tariff Schedule of the United..., the tariff-rate quota for tuna described in subheading 1604.14.22, HTSUS, is based on the apparent... subheading 1604.14.22, HTSUS. Any such tuna which is entered, or withdrawn from warehouse, for...

  16. 76 FR 27658 - Tuna-Tariff-Rate Quota; The Tariff-Rate Quota for Calendar Year 2011 Tuna Classifiable Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ... Year 2011 Tuna Classifiable Under Subheading 1604.14.22, Harmonized Tariff Schedule of the United... the tariff-rate quota for tuna described in subheading 1604.14.22, HTSUS, is based on the apparent... 1604.14.22, HTSUS. Any such tuna which is entered or withdrawn from warehouse for consumption...

  17. 78 FR 24430 - Tuna-Tariff Rate Quota; the Tariff-Rate Quota for Calendar Year 2013 Tuna Classifiable Under...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-25

    ... 2013 Tuna Classifiable Under Subheading 1604.14.22, Harmonized Tariff Schedule of the United States... tariff-rate quota for tuna described in subheading 1604.14.22, HTSUS, is based on the apparent United... subheading 1604.14.22, HTSUS. Any such tuna which is entered, or withdrawn from warehouse, for...

  18. Structure and function of tuna tail tendons.

    PubMed

    Shadwick, Robert E; Rapoport, H Scott; Fenger, Joelle M

    2002-12-01

    The caudal tendons in tunas and other scombrid fish link myotomal muscle directly to the caudal fin rays, and thus serve to transfer muscle power to the hydrofoil-like tail during swimming. These robust collagenous tendons have structural and mechanical similarity to tendons found in other vertebrates, notably the leg tendons of terrestrial mammals. Biochemical studies indicate that tuna tendon collagen is composed of the (alpha1)(2),alpha2 heterotrimer that is typical of vertebrate Type I collagen, while tuna skin collagen has the unusual alpha1,alpha2,alpha3 trimer previously described in the skin of some other teleost species. Tuna collagen, like that of other fish, has high solubility due to the presence of an acid-labile intermolecular cross-link. Unlike collagen in mammalian tendons, no differences related to cross-link maturation were detected among tendons in tuna ranging from 0.05 to 72 kg (approx. 0.25-6 years). Tendons excised post-mortem were subjected to load cycling to determine the modulus of elasticity and resilience (mean of 1.3 GPa and 90%, respectively). These material properties compare closely to those of leg tendons from adult mammals that can function as effective biological springs in terrestrial locomotion, but the breaking strength is substantially lower. Peak tendon forces recorded during steady swimming appear to impose strains of much less than 1% of tendon length, and no more than 1.5% during bursts. Thus, the caudal tendons in tunas do not appear to function as elastic storage elements, even at maximal swimming effort.

  19. Thawing of Frozen Dressed Tuna by Microwave Heating

    NASA Astrophysics Data System (ADS)

    Tanaka, Takeo; Nagasaki, Tasuku; Takahashi, Kenji

    Large sized frozen yellowfin tuna and southern bluefin tuna in dressed form (decapitated and gutted) were thawed by microwave (915 MHz) irradiation. Temperature rise of the tuna during thawing was measured. Quality of the tuna meat before and after thawing was compared with each other using objective quality index such as degree of discoloration (met-myoglobin ratio), freshness (K1 value) and taste cornponent (K2 value). Results are as follows : (1) Both frozen tunas were thawed fairly well within as short time as 30 min without any partial over heating. (2) No changes in met-myoglobin ratio, K1 and K2 values were observed in the cases of yellow fin tuna. Slight discoloration, however, occurred in southern bluefin tuna meat during microwave thawing. This problem has been left unsolved.

  20. Trophic influences on mercury accumulation in top pelagic predators from offshore New England waters of the northwest Atlantic Ocean.

    PubMed

    Teffer, Amy K; Staudinger, Michelle D; Taylor, David L; Juanes, Francis

    2014-10-01

    Trophic pathways and size-based bioaccumulation rates of total mercury were evaluated among recreationally caught albacore tuna (Thunnus alalunga), yellowfin tuna (Thunnus albacares), shortfin mako shark (Isurus oxyrinchus), thresher shark (Alopias vulpinus), and dolphinfish (Coryphaena hippurus) from offshore southern New England waters of the northwest Atlantic Ocean between 2008 and 2011. Mercury concentrations were highest in mako (2.65 ± 1.16 ppm) and thresher sharks (0.87 ± 0.71 ppm), and significantly lower in teleosts (albacore, 0.45 ± 0.14 ppm; yellowfin, 0.32 ± 0.09 ppm; dolphinfish, 0.20 ± 0.17 ppm). The relationship between body size and mercury concentration was positive and linear for tunas, and positive and exponential for sharks and dolphinfish. Mercury increased exponentially with δ (15)N values, a proxy for trophic position, across all species. Results demonstrate mercury levels are positively related to size, diet and trophic position in sharks, tunas, and dolphinfish, and the majority of fishes exhibited concentrations greater than the US EPA recommended limit.

  1. Developmental stages of fish blood flukes, Cardicola forsteri and Cardicola opisthorchis (Trematoda: Aporocotylidae), in their polychaete intermediate hosts collected at Pacific bluefin tuna culture sites in Japan.

    PubMed

    Ogawa, Kazuo; Shirakashi, Sho; Tani, Kazuki; Shin, Sang Phil; Ishimaru, Katsuya; Honryo, Tomoki; Sugihara, Yukitaka; Uchida, Hiro'omi

    2017-02-01

    Farming of Pacific bluefin tuna (PBT), Thunnus orientalis, is a rapidly growing industry in Japan. Aporocotylid blood flukes of the genus Cardicola comprising C. orientalis, C. opisthorchis and C. forsteri are parasites of economic importance for PBT farming. Recently, terebellid polychaetes have been identified as the intermediate hosts for all these parasites. We collected infected polychaetes, Terebella sp., the intermediate host of C. opisthorchis, from ropes and floats attached to tuna cages in Tsushima, Nagasaki Prefecture, Japan. Also, Neoamphitrite vigintipes (formerly as Amphitrite sp. sensu Shirakashi et al., 2016), the intermediate host of C. forsteri, were collected from culture cages in Kushimoto, Wakayama Prefecture, Japan. The terebellid intermediate hosts harbored the sporocysts and cercariae in their body cavity. Developmental stages of these blood flukes were molecularly identified using species specific PCR primers. In this paper, we describe the cercaria and sporocyst stages of C. opisthorchis and C. forsteri and compare their morphological characteristics among three Cardicola blood flukes infecting PBT. We also discuss phylogenetic relations of the six genera of the terebellid intermediate hosts (Artacama, Lanassa, Longicarpus, Terebella, Nicolea and Neoamphitrite) of blood flukes infecting marine fishes, based on their morphological characters.

  2. 21 CFR 161.190 - Canned tuna.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... alletteratus (Rafinesque, 1810)—Spotted tunny Euthynnus lineatus Kishinouye, 1920—Black skipjack tuna Euthynnus... approximately 1/2-inch deep and painted flat black inside and outside) so that after tamping and smoothing the... through a suitable rheostat. The stand is equipped with non-glossy black curtains on the side of...

  3. 21 CFR 161.190 - Canned tuna.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... alletteratus (Rafinesque, 1810)—Spotted tunny Euthynnus lineatus Kishinouye, 1920—Black skipjack tuna Euthynnus... approximately 1/2-inch deep and painted flat black inside and outside) so that after tamping and smoothing the... through a suitable rheostat. The stand is equipped with non-glossy black curtains on the side of...

  4. 21 CFR 161.190 - Canned tuna.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... alletteratus (Rafinesque, 1810)—Spotted tunny Euthynnus lineatus Kishinouye, 1920—Black skipjack tuna Euthynnus... approximately 1/2-inch deep and painted flat black inside and outside) so that after tamping and smoothing the... through a suitable rheostat. The stand is equipped with non-glossy black curtains on the side of...

  5. 21 CFR 161.190 - Canned tuna.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... alletteratus (Rafinesque, 1810)—Spotted tunny Euthynnus lineatus Kishinouye, 1920—Black skipjack tuna Euthynnus... approximately 1/2-inch deep and painted flat black inside and outside) so that after tamping and smoothing the... through a suitable rheostat. The stand is equipped with non-glossy black curtains on the side of...

  6. 21 CFR 161.190 - Canned tuna.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... alletteratus (Rafinesque, 1810)—Spotted tunny Euthynnus lineatus Kishinouye, 1920—Black skipjack tuna Euthynnus... approximately 1/2-inch deep and painted flat black inside and outside) so that after tamping and smoothing the... through a suitable rheostat. The stand is equipped with non-glossy black curtains on the side of...

  7. [Otolith microchemistry of tuna species: research progress].

    PubMed

    Zhu, Guo-ping

    2011-08-01

    Microchemistry analysis of trace elements and isotopes in fishes' calcified substances is an emerging approach to analyze the population structure, life history, and migration environmental history of fishes. With the increasing improvement of the researches and applications of otolith microchemistry, this approach has been a good tool for studying the ecology of tuna species. Currently, the research contents of tuna species' otolith microchemistry mainly include trace elements and isotopes, and the former is the emphasis and hotspot in applied research, playing a vital role in the researches of population partitioning, natal origin, migration environmental history, and life history of tuna species, especially bluefin tuna. However, most of the researches are focusing on the variation of otolith's Sr/Ca ratio, and there is no final conclusion on the relationships between the fractionation of isotopes C and O in otolith and the temperature. For the sake of exploiting the huge value of otolith microchemistry, it would be necessary to strengthen the researches on the deposition mechanisms of trace elements in otolith, and to analyze the spatio-temporal variations of various trace elements in otolith by comprehensive research methods.

  8. Kounis syndrome following canned tuna fish ingestion.

    PubMed

    De Gennaro, Luisa; Brunetti, Natale Daniele; Locuratolo, Nicola; Ruggiero, Massimo; Resta, Manuela; Diaferia, Giuseppe; Rana, Michele; Caldarola, Pasquale

    2016-12-20

    Kounis syndrome (KS) is a complex of cardiovascular symptoms and signs following either allergy or hypersensitivity and anaphylactic or anaphylactoid insults. We report the case of 57-year-old man, with hypertension and history of allergy, referred for facial rash and palpitations appeared after consumption of canned tuna fish. Suddenly, the patient collapsed: electrocardiogram showed ST-elevation in inferior leads. The patient was transferred from the spoke emergency room for coronary angio, which did not show any sign of coronary atherosclerosis. A transient coronary spasm was therefore hypothesized and the final diagnosis was KS. To the best of our knowledge, this is one of the first cases of KS following the ingestion of tuna fish. KS secondary to food allergy has also been reported, and shellfish ingestion has been considered as one of the most active KS inducer foods. Canned tuna fish too is well known as an allergy inducer. Tuna fish allergy should be considered, however, within the context of scombroid food poisoning, also called histamine fish poisoning. Fish with high levels of free histidine, the enzyme substrate converted to histamine by bacterial histidine decarboxylase, are those most often implicated in scombroid poisoning. Inflammatory mediators such as histamine constitute the pathophysiologic basis of Kounis hypersensitivity-associated acute coronary syndrome. Patients with coronary risk factors, allergic reaction after food ingestion, and suspected scombroid poisoning should be therefore carefully monitored for a prompt diagnosis of possible coronary complications.

  9. Measurement of Coefficient of Thermal Expansion of Tuna Fish

    NASA Astrophysics Data System (ADS)

    Ogawa, Yutaka

    Considering that gape and heave produced during the freezing of tuna fish derive from changes in the thermophysical properties of tuna fish itself during freezing, the coefficient of linear and cubical expansion of tuna meat were measured continuously between the temperature before freezing and during freezing. The results of measurement were shown that the coefficient of thermal expansion of tuna meat displayed special temperature dependence as sudden change at the boundary temperature of freezing beginning as summarized below: 1) the coefficient of linear expansion of tuna meat were anisotropic according to the tissue and structure of the fish body, but these properties varied according to the test temperature; and 2) the coefficient of cubical expansion during freezing assumed a maximal value when tuna meat was partially frozen.

  10. Habitat suitability of the Atlantic bluefin tuna by size class: An ecological niche approach

    NASA Astrophysics Data System (ADS)

    Druon, Jean-Noël; Fromentin, Jean-Marc; Hanke, Alex R.; Arrizabalaga, Haritz; Damalas, Dimitrios; Tičina, Vjekoslav; Quílez-Badia, Gemma; Ramirez, Karina; Arregui, Igor; Tserpes, George; Reglero, Patricia; Deflorio, Michele; Oray, Isik; Saadet Karakulak, F.; Megalofonou, Persefoni; Ceyhan, Tevfik; Grubišić, Leon; MacKenzie, Brian R.; Lamkin, John; Afonso, Pedro; Addis, Piero

    2016-03-01

    An ecological niche modelling (ENM) approach was used to predict the potential feeding and spawning habitats of small (5-25 kg, only feeding) and large (>25 kg) Atlantic bluefin tuna (ABFT), Thunnus thynnus, in the Mediterranean Sea, the North Atlantic and the Gulf of Mexico. The ENM was built bridging knowledge on ecological traits of ABFT (e.g. temperature tolerance, mobility, feeding and spawning strategy) with patterns of selected environmental variables (chlorophyll-a fronts and concentration, sea surface current and temperature, sea surface height anomaly) that were identified using an extensive set of precisely geo-located presence data. The results highlight a wider temperature tolerance for larger fish allowing them to feed in the northern - high chlorophyll levels - latitudes up to the Norwegian Sea in the eastern Atlantic and to the Gulf of Saint Lawrence in the western basin. Permanent suitable feeding habitat for small ABFT was predicted to be mostly located in temperate latitudes in the North Atlantic and in the Mediterranean Sea, as well as in subtropical waters off north-west Africa, while summer potential habitat in the Gulf of Mexico was found to be unsuitable for both small and large ABFTs. Potential spawning grounds were found to occur in the Gulf of Mexico from March-April in the south-east to April-May in the north, while favourable conditions evolve in the Mediterranean Sea from mid-May in the eastern to mid-July in the western basin. Other secondary potential spawning grounds not supported by observations were predicted in the Azores area and off Morocco to Senegal during July and August when extrapolating the model settings from the Gulf of Mexico into the North Atlantic. The presence of large ABFT off Florida and the Bahamas in spring was not explained by the model as is, however the environmental variables other than the sea surface height anomaly appeared to be favourable for spawning in part of this area. Defining key spatial and

  11. Depressed resilience of bluefin tuna in the western atlantic and age truncation.

    PubMed

    Secor, D H; Rooker, J R; Gahagan, B I; Siskey, M R; Wingate, R W

    2015-04-01

    Following intense overfishing in the 1970s, the western stock of Atlantic bluefin tuna (Thunnus thynnus) experienced a long period of depressed abundance, which has been attributed to failure of the population to periodically produce large numbers of juveniles, the western stock mixing with the more highly exploited eastern stock (fisheries in the Northeast Atlantic Ocean and Mediterranean Sea), and regime shift in the population's ecosystem resulting in lower replacement rates. To evaluate the presence of relatively strong years of juvenile production, we analyzed age structure from a recent sample of otoliths (ear stones) collected from the western stock (2011-2013, North Carolina, U.S.A., winter fishery). Mixing levels for the recent sample were analyzed using otolith stable isotopes to test whether age structure might be biased through immigration of eastern stock bluefin tuna. Age structure from historical samples collected from United States and Canadian fisheries (1975-1981) was compared with more recent samples (1996-2007) to examine whether demographic changes had occurred to the western stock that might have disrupted juvenile production. Relatively high juvenile production occurred in 2003, 2005, and 2006. Otolith stable isotope analysis showed that these recruitments were mostly of western stock origin. However, these high recruitments were >2-fold less than historical recruitment. We found substantial age truncation in the sampled fisheries. Half the historical sample was >20 years old (mean age = 20.1 [SD 3.7]; skewness = -0.3), whereas <5% of the recent sample was >20 years old (mean age = 13.4 [SD 3.8]; skewness = 1.3). Loss of age structure is consistent with changes in fishing selectivity and trends in the stock assessment used for management. We propose that fishing, as a forcing variable, brought about a threshold shift in the western stock toward lower biomass and production, a shift that emulates the regime shift hypothesis. An abbreviated

  12. Hydrodynamics and energy-saving swimming techniques of Pacific bluefin tuna.

    PubMed

    Takagi, Tsutomu; Tamura, Yumiko; Weihs, Daniel

    2013-11-07

    Weihs theoretically revealed that during the movement of fish with negative buoyancy, more kinetic energy is saved in the glide and upward (GAU) swimming mode than in the continuous horizontal swimming mode. Because kinetic energy saving depends on dynamic parameters such as the drag and lift of the body, the effects of variations in these parameters on energy saving for different species remain unknown. Here, the kinetic energy saving of Pacific bluefin tuna (PBT), Thunnus orientalis, exhibiting the GAU swimming mode was investigated. The dynamic properties of PBT were estimated by carrying out CFD analysis. The CFD model was produced by using a three-dimensional laser surface profiler, and the model was controlled such that it exhibited swimming motion similar to that of a live PBT swimming in a flume tank. The drag generated by tail beating, which significantly affects the kinetic energy during motion, was twice that generated in the glide mode. The faster the upward swimming speed, the lesser is the kinetic energy saving; therefore, when the upward swimming speed is more than twice the glide speed, there is no gain in the GAU mode. However, when SMR (Standard Metabolic Rate) is considered, if the energy based on SMR is assumed to be 30% of the total energy spent during motion, the most efficient upward swimming speed is 1.4 times the glide speed. The GAU swimming mode of PBT leads to energy saving during motion, and the upward swimming speed and the lift force produced by the pectoral fins for the most efficient drive are unique for different species of different sizes.

  13. Spatio-temporal population structuring and genetic diversity retention in depleted Atlantic Bluefin tuna of the Mediterranean Sea

    PubMed Central

    Riccioni, Giulia; Landi, Monica; Ferrara, Giorgia; Milano, Ilaria; Cariani, Alessia; Zane, Lorenzo; Sella, Massimo; Barbujani, Guido; Tinti, Fausto

    2010-01-01

    Fishery genetics have greatly changed our understanding of population dynamics and structuring in marine fish. In this study, we show that the Atlantic Bluefin tuna (ABFT, Thunnus thynnus), an oceanic predatory species exhibiting highly migratory behavior, large population size, and high potential for dispersal during early life stages, displays significant genetic differences over space and time, both at the fine and large scales of variation. We compared microsatellite variation of contemporary (n = 256) and historical (n = 99) biological samples of ABFTs of the central-western Mediterranean Sea, the latter dating back to the early 20th century. Measures of genetic differentiation and a general heterozygote deficit suggest that differences exist among population samples, both now and 96–80 years ago. Thus, ABFTs do not represent a single panmictic population in the Mediterranean Sea. Statistics designed to infer changes in population size, both from current and past genetic variation, suggest that some Mediterranean ABFT populations, although still not severely reduced in their genetic potential, might have suffered from demographic declines. The short-term estimates of effective population size are straddled on the minimum threshold (effective population size = 500) indicated to maintain genetic diversity and evolutionary potential across several generations in natural populations. PMID:20080643

  14. 50 CFR 300.225 - Eastern High Seas Special Management Area.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... following species or species groups: yellowfin tuna, bigeye tuna, albacore, skipjack tuna, swordfish, shark..., skipjack tuna, swordfish, shark, other; and (5) An indication of whether the vessel has engaged in or...

  15. 50 CFR 300.225 - Eastern High Seas Special Management Area.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... following species or species groups: yellowfin tuna, bigeye tuna, albacore, skipjack tuna, swordfish, shark..., skipjack tuna, swordfish, shark, other; and (5) An indication of whether the vessel has engaged in or...

  16. Trouble with tuna: two cases of scombrotoxin poisoning.

    PubMed Central

    Stell, I M

    1997-01-01

    Two cases of scombrotoxin poisoning after exposure to tuna are described, the second being unusual in that tinned, rather than fresh, tuna was involved. This relatively rare condition needs to be distinguished from an allergic reaction, for which it can easily be mistaken. Images p111-a PMID:9132185

  17. Environmental Load during the Distribution of Cultured Tuna

    NASA Astrophysics Data System (ADS)

    Sakai, Rirei; Watanabe, Manabu; Suzuki, Toru

    Tuna is the most favorite marine products for Japanese people. Most of them are consumed as Sashimi in Japan, and a half of them are imported. Cold transportation technology is essential to keep freshness of tuna during the oversea transportation. In the case of transporting tuna, ship transportation in ultra low temperature such as -60 °C is applied and also high speed transportation even by using airplane is practically used. On the other hand, it is a fact that such transportation processes of tuna are giving huge environmental load, though it has not been so much focused. Evaluation of cold transportation technologies from this environmental viewpoint must be important in the future. In this article, we compared CO2 emission during cold transportations of frozen tuna (marine transportation) and non-frozen tuna (air transportation) by using LCI analysis. As a result, CO2 emission of non-frozen tuna is found to be about four times greater than that of frozen tuna. This is due to the difference in the amount of freight per transportation of the airplane and the ship.

  18. 78 FR 36685 - Atlantic Highly Migratory Species; 2013 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... Species; 2013 Atlantic Bluefin Tuna Quota Specifications AGENCY: National Marine Fisheries Service (NMFS...: NMFS establishes 2013 quota specifications for the Atlantic bluefin tuna (BFT) fishery and closes the... Commission for the Conservation of Atlantic Tunas (ICCAT), as required by the Atlantic Tunas Convention...

  19. 78 FR 33240 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-04

    ... the overall EPO tuna catch. The number of purse seine vessels that have landed tuna in California...; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean AGENCY: National Marine... rule. SUMMARY: NMFS is issuing regulations under the Tuna Conventions Act of 1950 to...

  20. Sexual maturity in western Atlantic bluefin tuna

    PubMed Central

    Heinisch, Gilad; Rosenfeld, Hanna; Knapp, Jessica M.; Gordin, Hillel; Lutcavage, Molly E.

    2014-01-01

    We introduce a novel endocrine approach for assessing the unresolved matter of the timing of sexual maturation in western Atlantic bluefin tuna (ABFT), a highly migratory population whose status remains uncertain. Ratios of follicle stimulating hormone to luteinizing hormone, a sexual maturity indicator, in all ABFT ≥134 cm curved fork length (CFL) were <0.4, similar to Mediterranean spawners, indicating that western ABFT mature at considerably smaller sizes and at a much younger age than currently assumed (≥185 cm CFL). PMID:25431301

  1. 78 FR 20604 - Enhanced Document Requirements To Support Use of the Dolphin Safe Label on Tuna Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-05

    ... processors, other than tuna canners, of tuna product labeled dolphin-safe; and modify the reporting... processors, other than tuna canners, of tuna product labeled dolphin- safe; and to include modifications to a... the processor indicates the tuna is eligible to be labeled dolphin-safe under 50 CFR 216.91....

  2. Biology, fishery, conservation and management of Indian Ocean tuna fisheries

    NASA Astrophysics Data System (ADS)

    Gopalakrishna Pillai, N.; Satheeshkumar, Palanisamy

    2012-12-01

    The focus of the study is to explore the recent trend of the world tuna fishery with special reference to the Indian Ocean tuna fisheries and its conservation and sustainable management. In the Indian Ocean, tuna catches have increased rapidly from about 179959 t in 1980 to about 832246 t in 1995. They have continued to increase up to 2005; the catch that year was 1201465 t, forming about 26% of the world catch. Since 2006 onwards there has been a decline in the volume of catches and in 2008 the catch was only 913625 t. The Principal species caught in the Indian Ocean are skipjack and yellowfin. Western Indian Ocean contributed 78.2% and eastern Indian Ocean 21.8% of the total tuna production from the Indian Ocean. The Indian Ocean stock is currently overfished and IOTC has made some recommendations for management regulations aimed at sustaining the tuna stock. Fishing operations can cause ecological impacts of different types: by catches, damage of the habitat, mortalities caused by lost or discarded gear, pollution, generation of marine debris, etc. Periodic reassessment of the tuna potential is also required with adequate inputs from exploratory surveys as well as commercial landings and this may prevent any unsustainable trends in the development of the tuna fishing industry in the Indian Ocean.

  3. Tuna fish diet influences cat behavior. [Elevated levels of selenium and mercury in commercial tuna fish cat food

    SciTech Connect

    Houpt, K.A.; Essick, L.A.; Shaw, E.B.; Alo, D.K.; Gilmartin, J.E.; Gutenmann, W.H.; Littman, C.B.; Lisk, D.J.

    1988-01-01

    When observed in their home cages, cats fed commercial tuna fish cat food were less active, vocalized less, and spent more time on the floor and more time eating than cats fed commercial beef cat food. There were no differences in response to human handling between the two groups. There were no differences in learning ability on a two-choice point maze or in reversal learning in the same maze between beef- and tuna-fed cats. The behavior of the groups differed in a 15-min open field test only in the number of toys contacted. Cats fed the tuna had elevated tissue levels of mercury and selenium.

  4. Measurement of Young's Modulus and Poisson's Ratio of Tuna Fish

    NASA Astrophysics Data System (ADS)

    Ogawa, Yutaka; Hagura, Yoshio

    Considering that gape and heave produced during the freezing of tuna fish derive from changes in the mechanical properties of tuna fish itself during freezing,the Poisson's ratio and Young's modulus of tuna meat were measured at the respective temperature conditions of i) no freezing,ii) partial freezing,and iii) freezing. The results of measurement were shown that the mechanical properties of tuna meat displayed temperature dependence as sudden change at the boundary temperature of freezing beginning as summarized below: 1) the mechanical properties of tuna meat were anisotropic according to the tissue and structure of the fish body,but these properties greatly varied according to the test temperature;2) the Young's modulus of non-frozen tuna meat were approximately 50 KPa,but these became an extremely large value (approximately 4 GPa) after being frozen; and 3) the Poisson's ratio decreased as the frozen water percentage increased,but these displayed an approximate value of one or more.

  5. Monitoring of bisphenols in canned tuna from Italian markets.

    PubMed

    Fattore, Margherita; Russo, Giacomo; Barbato, Francesco; Grumetto, Lucia; Albrizio, Stefania

    2015-09-01

    Monitoring of food contamination from bisphenols is a necessary process for the consumers' risk assessment. A method for the quali-quantitative analysis of Bisphenol A (BPA), Bisphenol B (BPB), Bisphenol A Diglycidyl Ether (BADGE), and Bisphenol F Diglycidyl Ether (BFDGE), by liquid chromatography with fluorescence detection (LC-FD), was performed and validated for their determination in 33 samples of tuna fish, canned in either oil or aqueous medium. Samples were collected in Italian markets. Tuna and the correspondent preservation medium were analyzed separately. Detected levels of bisphenols ranged from 19.1 to 187.0 ng/g in tuna matrix and from 6.3 to 66.9 ng/mL in oil medium. No bisphenols were found in aqueous medium. At least one of the analytes was found in 83% of the tuna samples in oil medium, whereas tuna samples in aqueous medium showed BPA alone in 67% of samples. 21% of the oil medium samples resulted positive for at least one bisphenol. On the basis of measured concentrations and general daily ingestion rate of canned tuna fish, the probable daily intake of BPA for Italian population was calculated.

  6. 50 CFR 216.95 - Official mark for “Dolphin-safe” tuna products.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Official mark for âDolphin-safeâ tuna... AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.95 Official mark for “Dolphin-safe... Department of Commerce that may be used to label tuna products that meet the “dolphin-safe” standards...

  7. 50 CFR 216.95 - Official mark for “Dolphin-safe” tuna products.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Official mark for âDolphin-safeâ tuna... AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.95 Official mark for “Dolphin-safe... Department of Commerce that may be used to label tuna products that meet the “dolphin-safe” standards...

  8. 50 CFR 216.95 - Official mark for “Dolphin-safe” tuna products.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Official mark for âDolphin-safeâ tuna... AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.95 Official mark for “Dolphin-safe... Department of Commerce that may be used to label tuna products that meet the “dolphin-safe” standards...

  9. 50 CFR 216.95 - Official mark for “Dolphin-safe” tuna products.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Official mark for âDolphin-safeâ tuna... AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.95 Official mark for “Dolphin-safe... Department of Commerce that may be used to label tuna products that meet the “dolphin-safe” standards...

  10. 50 CFR 216.95 - Official mark for “Dolphin-safe” tuna products.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Official mark for âDolphin-safeâ tuna... AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.95 Official mark for “Dolphin-safe... Department of Commerce that may be used to label tuna products that meet the “dolphin-safe” standards...

  11. 75 FR 54078 - International Fisheries; Pacific Tuna Fisheries; Vessel Capacity Limit in the Purse Seine Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-03

    ... (Resolution C-02-03) to address the problem of excess capacity in the tuna purse-seine fleet operating in the... for tuna in the IATTC Convention Area. However, these vessels (class size 5 and under purse seine... satisfying its obligations under the Tuna Conventions Act and not exceeding its allotted capacity in...

  12. 76 FR 31351 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-31

    ... availability of Office of Vessel Activities Policy Letter 11-05 regarding Distant Water Tuna Fleet vessels... Eligibility on Distant Water Tuna Fleet Vessels policy.\\1\\ A general summary of the comments received and the... SECURITY Coast Guard Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna...

  13. 76 FR 3646 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-20

    ... availability of a draft policy regarding distant water tuna fleet vessels manning exemption eligibility and... SECURITY Coast Guard Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet... Eligibility on Distant Water Tuna Fleet Vessels. DATES: Comments and related material must either be...

  14. 75 FR 30730 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... retention limit adjustment. SUMMARY: NMFS has determined that the Atlantic tunas General category daily Atlantic bluefin tuna (BFT) retention limit should be adjusted for the June through August 2010 time...

  15. 76 FR 32086 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-03

    ... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... retention limit adjustment. SUMMARY: NMFS has determined that the Atlantic tunas General category daily Atlantic bluefin tuna (BFT) retention limit should be adjusted for the June through August 2011 time...

  16. 76 FR 52886 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... retention limit adjustment. SUMMARY: NMFS has determined that the Atlantic tunas General category daily Atlantic bluefin tuna (BFT) retention limit should be adjusted from one to three large medium or giant...

  17. Global population trajectories of tunas and their relatives

    PubMed Central

    Juan-Jordá, Maria José; Mosqueira, Iago; Cooper, Andrew B.; Freire, Juan; Dulvy, Nicholas K.

    2011-01-01

    Tunas and their relatives dominate the world's largest ecosystems and sustain some of the most valuable fisheries. The impacts of fishing on these species have been debated intensively over the past decade, giving rise to divergent views on the scale and extent of the impacts of fisheries on pelagic ecosystems. We use all available age-structured stock assessments to evaluate the adult biomass trajectories and exploitation status of 26 populations of tunas and their relatives (17 tunas, 5 mackerels, and 4 Spanish mackerels) from 1954 to 2006. Overall, populations have declined, on average, by 60% over the past half century, but the decline in the total adult biomass is lower (52%), driven by a few abundant populations. The trajectories of individual populations depend on the interaction between life histories, ecology, and fishing pressure. The steepest declines are exhibited by two distinct groups: the largest, longest lived, highest value temperate tunas and the smaller, short-lived mackerels, both with most of their populations being overexploited. The remaining populations, mostly tropical tunas, have been fished down to approximately maximum sustainable yield levels, preventing further expansion of catches in these fisheries. Fishing mortality has increased steadily to the point where around 12.5% of the tunas and their relatives are caught each year globally. Overcapacity of these fisheries is jeopardizing their long-term sustainability. To guarantee higher catches, stabilize profits, and reduce collateral impacts on marine ecosystems requires the rebuilding of overexploited populations and stricter management measures to reduce overcapacity and regulate threatening trade. PMID:22143785

  18. Occurrence of toxic metals (Hg, Cd and Pb) in fresh and canned tuna: public health implications.

    PubMed

    Storelli, Maria M; Barone, Grazia; Cuttone, Giuseppe; Giungato, Daniele; Garofalo, Rita

    2010-11-01

    Hg, Pb and Cd levels in fresh and canned tuna were determined and assessed by comparing element levels in these samples with maximum permissible limits set by European legislation. The estimated weekly intakes by human consuming both fresh and canned tuna were also evaluated for possible consumer health risks. Among tested metals, Hg had the highest concentrations, followed by Pb and Cd either in fresh tuna or canned tuna. None of the tested samples surpassed the European regulatory limits fixed for Cd and Pb, whereas 8.9% of the tuna cans and 20% of fresh tuna samples exceeded standard for Hg. The size of tuna was a determining factor of Hg burden. A high intake of Hg surpassing the toxicological reference value established by WHO, was associated with consumption of larger size tuna specimens. Also canned tuna consumption with Hg concentrations higher than 1 μg kg(-1), strongly increased the consumer exposure. In contrast, Cd and Pb weekly intakes through consumption either of fresh tuna or canned tuna did not exceed the toxicological reference values established by WHO, and consequently there was no human health risk. A continuous surveillance system of Hg content in these fishery products is crucial for consumer protection.

  19. Baseline concentration of Polonium-210 ((210)Po) in tuna fish.

    PubMed

    Khan, M Feroz; Wesley, S Godwin

    2016-06-15

    Several species of tuna fish were analyzed for (210)Po content in their edible muscle tissues. This study was carried out as a part of baseline data generation around a large nuclear power plant situated at Kudankulam, southeast coast of India. The concentration of (210)Po in the muscle tissue ranged from 40.9±5.2 to 92.5±7.9Bq/kg of fresh fish, and the highest activity was recorded for the tuna Euthynnus affinis and the lowest for Auxis thazard. The committed effective dose to the local residents was calculated to be 62.7-141.8μSvyear(-1).

  20. El Nino Southern Oscillation and Tuna in the Western Pacific

    NASA Technical Reports Server (NTRS)

    Lehodey, P.; Bertignac, M.; Hampton, J.; Lewis, A.; Picaut, J.

    1997-01-01

    Nearly 70% of the world's annual tuna harvest, currently 3.2 million tonnes, comes from the Pacific Ocean. Skipjack tuna (Katsuwonus pelamis) dominate the catch. Although skipjack are distributed in the surface mixed layer throughout the equatorial and subtropical Pacific, catches are highest in the western equatorial Pacific warm pool, a region characterized by low primary productivity rates that has the warmest surface waters of the world's oceans. Assessments of tuna stocks indicate that recent western Pacific skipjack catches approaching one million tonnes annually are sustainable. The warm pool, which is fundamental to the El Nino Southern Oscillation (ENSO) and the Earth's climate in general, must therefore also provide a habitat capable of supporting this highly productive tuna population. Here we show that apparent spatial shifts in the skipjack population are linked to large zonal displacements of the warm pool that occur during ENSO events. This relationship can be used to predict (several months in advance) the region of highest skipjack abundance, within a fishing ground extending over 6,000 km along the Equator.

  1. Radiation hydrolysate of tuna cooking juice with enhanced antioxidant properties

    NASA Astrophysics Data System (ADS)

    Choi, Jong-il; Sung, Nak-Yun; Lee, Ju-Woon

    2012-08-01

    Tuna protein hydrolysates are of increasing interest because of their potential application as a source of bioactive peptides. Large amounts of tuna cooking juice with proteins and extracts are produced during the process of tuna canning, and these cooking juice wastes cause environmental problems. Therefore, in this study, cooking juice proteins were hydrolyzed by irradiation for their utilization as functional additives. The degree of hydrolysis of tuna cooking juice protein increased from 0% to 15.1% at the absorbed doses of 50 kGy. To investigate the antioxidant activity of the hydrolysate, it was performed the ferric reducing antioxidant power (FRAP) assay, and the lipid peroxidation inhibitory and superoxide radical scavenging activities were measured. The FRAP values increased from 1470 μM to 1930 μM and IC50 on superoxide anion was decreased from 3.91 μg/mL to 1.29 μg/mL at 50 kGy. All of the antioxidant activities were increased in the hydrolysate, suggesting that radiation hydrolysis, which is a simple process that does not require an additive catalysts or an inactivation step, is a promising method for food and environmental industries.

  2. Importance of large-scale bathymetry features on 2011 Tohoku tsunami waveforms through comparison of simulations with the spatially dense ALBACORE OBS array data

    NASA Astrophysics Data System (ADS)

    Kohler, M. D.; Lynett, P. J.; Legg, M. R.; Weeraratne, D. S.

    2012-12-01

    In March 2011, a deployment of ocean bottom seismometers (OBSs) off the coast of Southern California recorded the tsunami resulting from the Mw=9.0 Tohoku, Japan earthquake with very high spatial resolution. The ALBACORE (Asthenosphere and Lithosphere Broadband Architecture from the California Offshore Region Experiment) OBS array spanned a region that was 150 km north-south by 400 km east-west, extending into deep open ocean west of the Patton escarpment. In that array, 22 stations with a spacing of 75 km had differential pressure gauges (DPGs) that recorded water pressure waveform data continuously at 50 samples/second. The DPG tsunami records across the entire array show multiple large-amplitude, coherent phases arriving one hour to more than 36 hours after the initial tsunami phase. To determine the source of the large-amplitude coherent phases, gravity ocean wave propagation calculations were carried out for the Pacific Ocean. Simulated pressure waveforms were compared with data for the ALBACORE stations, as well as for the NOAA DART buoys. The linear, non-dispersive shallow-water simulations include bottom frictional effects, and use the USGS NEIC Tohoku slip model and ETOPO2 (two-minute spatial resolution) bathymetry. The predicted travel times of the initial arrivals are found to be less than 1% different from the observed travel times in the southern California ALBACORE DPG data. In order to gauge the effects of large-scale features in Pacific Ocean bathymetry, several large-scale features were individually removed, and simulations were carried out for the modified bathymetry. The removed features include the Emperor Seamount chain, Hawaiian Islands, Oceania, French Polynesia, and the South American coastline. The results show that the removal of these features has an effect on the arrival time of the phases that depends on the feature proximity to the direct path, but their removal does not have a significant effect on the frequency content or phase

  3. 75 FR 36619 - International Fisheries; South Pacific Tuna Fisheries; Procedures to Request Licenses and a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-28

    ... are issued by the Pacific Islands Forum Fisheries Agency (FFA), based in Honiara, Solomon Islands... fishing for albacore by the trolling method to fish in the high seas portion of the Treaty Area. However..., Marshall Islands, Nauru, New Zealand, Niue, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga,...

  4. Massive consumption of gelatinous plankton by Mediterranean apex predators.

    PubMed

    Cardona, Luis; Álvarez de Quevedo, Irene; Borrell, Assumpció; Aguilar, Alex

    2012-01-01

    Stable isotopes of carbon and nitrogen were used to test the hypothesis that stomach content analysis has systematically overlooked the consumption of gelatinous zooplankton by pelagic mesopredators and apex predators. The results strongly supported a major role of gelatinous plankton in the diet of bluefin tuna (Thunnus thynnus), little tunny (Euthynnus alletteratus), spearfish (Tetrapturus belone) and swordfish (Xiphias gladius). Loggerhead sea turtles (Caretta caretta) in the oceanic stage and ocean sunfish (Mola mola) also primarily relied on gelatinous zooplankton. In contrast, stable isotope ratios ruled out any relevant consumption of gelatinous plankton by bluefish (Pomatomus saltatrix), blue shark (Prionace glauca), leerfish (Lichia amia), bonito (Sarda sarda), striped dolphin (Stenella caerueloalba) and loggerhead sea turtles (Caretta caretta) in the neritic stage, all of which primarily relied on fish and squid. Fin whales (Balaenoptera physalus) were confirmed as crustacean consumers. The ratios of stable isotopes in albacore (Thunnus alalunga), amberjack (Seriola dumerili), blue butterfish (Stromaeus fiatola), bullet tuna (Auxis rochei), dolphinfish (Coryphaena hyppurus), horse mackerel (Trachurus trachurus), mackerel (Scomber scombrus) and pompano (Trachinotus ovatus) were consistent with mixed diets revealed by stomach content analysis, including nekton and crustaceans, but the consumption of gelatinous plankton could not be ruled out completely. In conclusion, the jellyvorous guild in the Mediterranean integrates two specialists (ocean sunfish and loggerhead sea turtles in the oceanic stage) and several opportunists (bluefin tuna, little tunny, spearfish, swordfish and, perhaps, blue butterfish), most of them with shrinking populations due to overfishing.

  5. Massive Consumption of Gelatinous Plankton by Mediterranean Apex Predators

    PubMed Central

    Cardona, Luis; Álvarez de Quevedo, Irene; Borrell, Assumpció; Aguilar, Alex

    2012-01-01

    Stable isotopes of carbon and nitrogen were used to test the hypothesis that stomach content analysis has systematically overlooked the consumption of gelatinous zooplankton by pelagic mesopredators and apex predators. The results strongly supported a major role of gelatinous plankton in the diet of bluefin tuna (Thunnus thynnus), little tunny (Euthynnus alletteratus), spearfish (Tetrapturus belone) and swordfish (Xiphias gladius). Loggerhead sea turtles (Caretta caretta) in the oceanic stage and ocean sunfish (Mola mola) also primarily relied on gelatinous zooplankton. In contrast, stable isotope ratios ruled out any relevant consumption of gelatinous plankton by bluefish (Pomatomus saltatrix), blue shark (Prionace glauca), leerfish (Lichia amia), bonito (Sarda sarda), striped dolphin (Stenella caerueloalba) and loggerhead sea turtles (Caretta caretta) in the neritic stage, all of which primarily relied on fish and squid. Fin whales (Balaenoptera physalus) were confirmed as crustacean consumers. The ratios of stable isotopes in albacore (Thunnus alalunga), amberjack (Seriola dumerili), blue butterfish (Stromaeus fiatola), bullet tuna (Auxis rochei), dolphinfish (Coryphaena hyppurus), horse mackerel (Trachurus trachurus), mackerel (Scomber scombrus) and pompano (Trachinotus ovatus) were consistent with mixed diets revealed by stomach content analysis, including nekton and crustaceans, but the consumption of gelatinous plankton could not be ruled out completely. In conclusion, the jellyvorous guild in the Mediterranean integrates two specialists (ocean sunfish and loggerhead sea turtles in the oceanic stage) and several opportunists (bluefin tuna, little tunny, spearfish, swordfish and, perhaps, blue butterfish), most of them with shrinking populations due to overfishing. PMID:22470416

  6. Effect of different types of heat processing on chemical changes in tuna.

    PubMed

    Stephen, Nimish Mol; Jeya Shakila, R; Jeyasekaran, G; Sukumar, D

    2010-03-01

    The chemical changes in skipjack tuna (Katsuwonus pelamis) subjected to cooking, frying, canning and microwave heating were studied. Raw tuna contained an unusual fatty acid C16:3 in high proportion (29.3%) followed by C18:2, C24:1, C16:0 and C18:3. Health beneficial fatty acids, eicosapentaenoic acid (EPA) (1.67%) and docosahexaenoic acid (DHA) (2.50%), were quite low with ω-3/ω-6 ratio 0.28. The total saturated fatty acids suffered major loss in fried (70%) and canned tuna (40%) due to loss of C16:0, C14:0 and C22:0. The monounsaturated fatty acids content increased (38%) in cooked and microwave heated tuna due to C24:1. The polyunsaturated fatty acids content increased in fried (50%) and canned (25%) tuna due to the uptake of frying and filling oil, respectively during processing. The loss of health beneficial ω-3 fatty acids, EPA and DHA were minimum in cooked tuna followed by microwave heated tuna. Canning totally destroyed these fatty acids. In fried tuna, the losses of EPA and DHA were 70 and 85%, respectively. Thiobarbituric acid - reactive substances values increased in heat processed tuna. Cholesterol increased in canned and microwave heated tuna but not in cooked tuna. Reduction of cholesterol in fried tuna was due to its migration into frying oil. This study indicated that cooking and microwave heating are the better processing methods to retain the health beneficial ω-3 fatty acids in comparison to frying and canning.

  7. Front variability and surface ocean features of the presumed southern bluefin tuna spawning grounds in the tropical southeast Indian Ocean

    NASA Astrophysics Data System (ADS)

    Nieblas, Anne-Elise; Demarcq, Hervé; Drushka, Kyla; Sloyan, Bernadette; Bonhommeau, Sylvain

    2014-09-01

    The southern bluefin tuna (SBT, Thunnus maccoyii) is an ecologically and economically valuable fish. However, surprisingly little is known about its critical early life history, a period when mortality is several orders of magnitude higher than at any other life stage, and when larvae are highly sensitive to environmental conditions. Ocean fronts can be important in creating favourable spawning conditions, as they are a convergence of water masses with different properties that can concentrate planktonic particles and lead to enhanced productivity. In this study, we examine the front activity within the only region where SBT have been observed to spawn: the tropical southeast Indian Ocean between Indonesia and Australia (10°S-20°S, 105°E-125°E). We investigate front activity and its relationship to ocean dynamics and surface features of the region. Results are also presented for the entire Indian Ocean (30°N-45°S, 20°E-140°E) to provide a background context. We use an extension of the Cayula and Cornillon algorithm to detect ocean fronts from satellite images of sea surface temperature (SST) and chlorophyll-a concentration (chl-a). Front occurrence represents the probability of occurrence of a front at each pixel of an image. Front intensity represents the magnitude of the difference between the two water masses that make up a front. Relative to the rest of the Indian Ocean, both SST and chl-a fronts in the offshore spawning region are persistent in occurrence and weak in intensity. Front occurrence and intensity along the Australian coast are high, with persistent and intense fronts found along the northwest and west coasts. Fronts in the tropical southeast Indian Ocean are shown to have strong annual variability and some moderate interannual variability. SST front occurrence is found to lead the Southern Oscillation Index by one year, potentially linked to warming and wind anomalies in the Indian Ocean. The surface ocean characteristics of the offshore

  8. 76 FR 67790 - Advisory Committee to the U.S. Section of the Inter-American Tropical Tuna Commission (Committee...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... Advisory Committee to the U.S. Section of the IATTC was established pursuant to Section 4 of the Tuna... major U.S. tuna harvesting, processing, and marketing sectors, as well as recreational fishing...

  9. Convergent evolution in mechanical design of lamnid sharks and tunas.

    PubMed

    Donley, Jeanine M; Sepulveda, Chugey A; Konstantinidis, Peter; Gemballa, Sven; Shadwick, Robert E

    2004-05-06

    The evolution of 'thunniform' body shapes in several different groups of vertebrates, including whales, ichthyosaurs and several species of large pelagic fishes supports the view that physical and hydromechanical demands provided important selection pressures to optimize body design for locomotion during vertebrate evolution. Recognition of morphological similarities between lamnid sharks (the most well known being the great white and the mako) and tunas has led to a general expectation that they also have converged in their functional design; however, no quantitative data exist on the mechanical performance of the locomotor system in lamnid sharks. Here we examine the swimming kinematics, in vivo muscle dynamics and functional morphology of the force-transmission system in a lamnid shark, and show that the evolutionary convergence in body shape and mechanical design between the distantly related lamnids and tunas is much more than skin deep; it extends to the depths of the myotendinous architecture and the mechanical basis for propulsive movements. We demonstrate that not only have lamnids and tunas converged to a much greater extent than previously known, but they have also developed morphological and functional adaptations in their locomotor systems that are unlike virtually all other fishes.

  10. Biomagnifications of mercury and methylmercury in tuna and mackerel.

    PubMed

    Hajeb, P; Jinap, S; Ahmad, I

    2010-12-01

    Seawater may be contaminated by harmful substances, including toxic elements released by human activities. The present study evaluates the total mercury and methylmercury concentrations and their correlations to fish body size in longtail tuna and short-bodied mackerel from Chendring, Kuantan, at east coast and Kuala Perlis at west costs of Peninsular Malaysia during May to November 2007. Total mercury and methylmercury in muscle tissue of 69 samples of longtail tuna and short-bodied mackerel, ranged from 0.180 to 1.460 μg/g and 0.0.169-0.973 μg/g and 0.251-1.470 μg/g and 0.202-1.352, whereas the methylmercury to total mercury ratio ranged from 70% to 83%, respectively. Samples of both species from the east coast showed higher levels of mercury compared to those from west coast. In all of the locations, significant positive correlations were found between fish body weight and mercury content (R(2) > 0.470). The estimated weekly intake of total mercury and methylmercury from the consumption 66.33 g/week of short-bodied mackerel and 18.34 g/week of longtail tuna (based on local dietry survey) was found to be lower than the maximum limit of 5 and 1.5 μg/kg bodyweight established by FAO/WHO and codex, respectively.

  11. Skipjack tuna as a bioindicator of contamination by perfluorinated compounds in the oceans.

    PubMed

    Hart, Kimberly; Kannan, Kurunthachalam; Tao, Lin; Takahashi, Shin; Tanabe, Shinsuke

    2008-09-15

    Perfluorinated chemicals (PFCs) have emerged as global environmental contaminants. Studies have reported the widespread occurrence of PFCs in biota from marine coastal waters and in remote polar regions. However, few studies have reported the distribution of PFCs in biota from offshore waters and open oceans. In this study, concentrations of nine PFCs were determined in the livers of 60 skipjack tuna (Katsuwonus pelamis) collected from offshore waters and the open ocean along the Pacific Rim, including the Sea of Japan, the East China Sea, the Indian Ocean, and the Western North Pacific Ocean, during 1997-1999. At least one of the nine PFCs was found in every tuna sample analyzed. Overall, perfluorooctanesulfonate (PFOS) and perfluoroundecanoic acid (PFUnDA) were the predominant compounds found in livers of tuna at concentrations of <1-58.9 and <1-31.6 ng/g, wet wt, respectively. Long-chain perfluorocarboxylates such as perfluorodecanoic acid (PFDA) and perfluorododecanoic acid (PFDoDA) were common in the tuna livers. In livers of tuna from several offshore and open-ocean locations, concentrations of PFUnDA were greater than the concentrations of PFOS. The profiles and concentrations of PFCs in tuna livers suggest that the sources in East Asia are dominated by long-chain perfluorocarboxylates, especially PFUnDA. High concentrations of PFUnDA in tuna may indicate a shift in sources of PFCs in East Asia. The spatial distribution of PFOS in skipjack tuna reflected the concentrations previously reported in seawater samples from the Pacific and Indian Oceans, suggesting that tuna are good bioindicators of pollution by PFOS. Despite its predominance in ocean waters, PFOA was rarely found in tuna livers, indicative of the low bioaccumulation potential of this compound. Our study establishes baseline concentrations of PFCs in skipjack tuna from the oceans of the Asia-Pacific region, enabling future temporal trend studies of PFCs in oceans.

  12. 50 CFR 216.92 - Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Dolphin-safe requirements for tuna... MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.92 Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels. (a)...

  13. 50 CFR 216.92 - Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 10 2012-10-01 2012-10-01 false Dolphin-safe requirements for tuna... MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.92 Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels. (a)...

  14. 50 CFR 216.92 - Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 9 2011-10-01 2011-10-01 false Dolphin-safe requirements for tuna... MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.92 Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels. (a)...

  15. 50 CFR 216.92 - Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 10 2014-10-01 2014-10-01 false Dolphin-safe requirements for tuna... MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.92 Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels. (a)...

  16. 50 CFR 216.92 - Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 10 2013-10-01 2013-10-01 false Dolphin-safe requirements for tuna... MAMMALS REGULATIONS GOVERNING THE TAKING AND IMPORTING OF MARINE MAMMALS Dolphin Safe Tuna Labeling § 216.92 Dolphin-safe requirements for tuna harvested in the ETP by large purse seine vessels. (a)...

  17. 75 FR 22418 - The Tariff-Rate Quota for Calendar Year 2010 Tuna Classifiable Under Subheading 1604.14.22...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ... Year 2010 Tuna Classifiable Under Subheading 1604.14.22, Harmonized Tariff Schedule of the United... the tariff-rate quota for tuna described in subheading 1604.14.22, HTSUS, is based on the apparent... 1604.14.22, HTSUS. Any such tuna which is entered or withdrawn from warehouse for consumption...

  18. 77 FR 31546 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-29

    ... National Oceanic and Atmospheric Administration 50 CFR Part 635 RIN 0648-XC035 Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... area fishery for large medium and giant Atlantic bluefin tuna (BFT) for the remainder of 2012....

  19. 77 FR 73969 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-12

    ... member of the IATTC and to reduce overfishing of the stock. DATES: Comments must be submitted in writing... are an important step for reducing the overfishing of bluefin tuna. In 2011, NMFS determined overfishing is occurring on Pacific bluefin tuna based on stock assessment results of the...

  20. Separation of gonadotropic fractions with different species specificities from tuna pituitaries

    SciTech Connect

    Ando, H.; Ishii, S.

    1988-05-01

    Eight different gonadotropic glycoprotein fractions were separated from the acetone-dried powder of yellow fin tuna pituitary glands by successive chromatographies on Superose 12 for gel filtration and Mono Q for anion exchange using the Pharmacia fast protein liquid chromatography system. This was preceded by preliminary separations using an ammonium sulfate precipitation method and affinity chromatography on concanavalin A-Sepharose. For biological characterization, we employed two radioreceptor assay systems, one using goby testis plasma membranes and silver carp GTH as the receptor and radioligand, respectively, and the other using testis plasma membranes of the yellow fin tuna and gonadotropin of the same species, respectively. We also employed two testicular cyclic AMP accumulation bioassay methods in vitro, one with the goby testis and the other with the mackerel testis. The least acidic fraction after Mono Q was further separated into four subfractions by rechromatography with Mono Q. They were strongly active in the tuna and mackerel assays but almost inactive in the goby assays. They were referred to as tuna-type tuna gonadotropin. In contrast, the most acidic fraction obtained after the first Mono Q was active in the goby assays but almost inactive in the tuna and mackerel assays. It was referred to as goby-type tuna gonadotropin. The intermediate fractions were active on both assays and are considered to be mixtures of tuna-type and goby-type gonadotropins. The reason for the presence of gonadotropin inactive to homologous species is discussed from the evolutionary viewpoint.

  1. Predicting the Distribution of Yellowfin Tuna in Philippine Waters

    NASA Astrophysics Data System (ADS)

    Perez, G. J. P.; Leonardo, E. M.

    2015-12-01

    The Philippines is considered as a major tuna producer in the Western and Central Pacific Ocean, both for domestic consumption and on industrial scale. However, with the ever-increasing demand of growing population, it has always been a challenge to achieve sustainable fishing. The creation of satellite-derived potential fishing zone maps is a technology that has been adopted by advanced countries for almost three decades already and has led to reduction in search times by up to 40%. In this study, a Generalized Additive Model (GAM) is developed to predict the distribution of the Yellowfin tuna species in seas surrounding the Philippines based on the Catch-Per-Unit-Effort (CPUE) index. Level 3 gridded chlorophyll-a and sea surface temperature from the Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Aqua satellite of the National Aeronautics and Space Administration (NASA) are the main input parameters of the model. Chlorophyll-a is linked with the presence of phytoplankton, which indicates primary productivity and suggests potential regions of fish aggregation. Fish also prefers to stay in regions where the temperature is stable, thus the sea surface temperature fronts serve as a guide to locate concentrations of fish school. Historical monthly tuna catch data from Western and Central Pacific Commissions (WCPFC) is used to train the model. The resulting predictions are converted to potential fishing zone maps and are evaluated within and beyond the historical time range of the training data used. Diagnostic tests involving adjusted R2 value, GAM residual plots and root mean square error value are used to assess the accuracy of the model. The generated maps were able to confirm locations of known tuna fishing grounds in Mindanao and other parts of the country, as well us detect their seasonality and interannual variability. To improve the performance of the model, ancillary data such as surface winds reanalysis from National Centers for

  2. Behavior of Salmonella and Listeria monocytogenes in Raw Yellowfin Tuna during Cold Storage

    PubMed Central

    Liu, Chengchu; Mou, Jing; Su, Yi-Cheng

    2016-01-01

    Behavior of Salmonella and Listeria monocytogenes in raw yellowfin tuna during refrigeration and frozen storage were studied. Growth of Salmonella was inhibited in tuna during refrigerated storage, while L. monocytogenes was able to multiply significantly during refrigerated storage. Populations of Salmonella in tuna were reduced by 1 to 2 log after 12 days of storage at 5–7 °C, regardless levels of contamination. However, populations of L. monocytogenes Scott A, M0507, and SFL0404 in inoculated tuna (104–105 CFU/g) increased by 3.31, 3.56, and 3.98 log CFU/g, respectively, after 12 days of storage at 5–7 °C. Similar increases of L. monocytogenes cells were observed in tuna meat with a lower inoculation level (102–103 CFU/g). Populations of Salmonella and L. monocytogenes declined gradually in tuna samples over 84 days (12 weeks) of frozen storage at −18 °C with Salmonella Newport 6962 being decreased to undetectable level (<10 CFU/g) from an initial level of 103 log CFU/g after 42 days of frozen storage. These results demonstrate that tuna meat intended for raw consumption must be handled properly from farm to table to reduce the risks of foodborne illness caused by Salmonella and L. monocytogenes. PMID:28231111

  3. First records of parasitic copepods (Crustacea, Siphonostomatoida) from marine fishes in Korea.

    PubMed

    Venmathi Maran, B A; Soh, H Y; Hwang, U W; Chang, C Y; Myoung, J G

    2015-06-01

    The knowledge of the biodiversity of parasitic copepods in South Korea is increasing. Interestingly we report here, some parasitic copepods considered as the first record of findings from Korea. Nine species of parasitic copepods (Siphonostomatoida) including six genera of three different families [Caligidae (7), Lernaeopodidae (1), Lernanthropidae (1)] were recovered from eight species of wild fishes in Korea: 1) Caligus hoplognathi Yamaguti & Yamasu, 1959 (♀, ♂) from the body surface of barred knifejaw Oplegnathus fasciatus (Temminck & Schlegel); 2) Caligus lagocephali Pillai, 1961 (♀) from the gills of panther puffer Takifugu pardalis (Temminck & Schlegel); 3) Euryphorus brachypterus (Gerstaecker, 1853) (♀, ♂) from the opercular cavity of Atlantic bluefin tuna Thunnus thynnus (Linnaeus); 4) Euryphorus nordmanni Milne Edwards, 1840 (♀, ♂) from the opercular cavity of common dolphin fish Coryphaena hippurus Linnaeus; 5) Gloiopotes huttoni (Thomson) (♀, ♂) from the body surface of black marlin Istiompax indica (Cuvier); 6) Lepeophtheirus hapalogenyos Yamaguti & Yamasu, 1959 (♀) from the gill filaments of O. fasciatus; 7) Lepeophtheirus sekii Yamaguti, 1936 (♀, ♂) from the body surface of red seabream Pagrus major (Temminck & Schlegel); 8) Brachiella thynni Cuvier, 1830 (♀) from the body surface of longfin tuna or albacore Thunnus alalunga (Bonnaterre); 9) Lernanthropinus sphyraenae (Yamaguti & Yamasu, 1959) (♀) from the gill filaments of moon fish Mene maculata (Bloch & Schneider). Since the female was already reported in Korea, it is a new record for the male of C. hoplognathi. A checklist for the parasitic copepods of the family Caligidae, Lernaeopodidae and Lernanthropidae of Korea is provided.

  4. 76 FR 38620 - International Fisheries; Atlantic Highly Migratory Species; Bluefin Tuna Import, Export, Re-Export

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-01

    ...; Bluefin Tuna Import, Export, Re-Export AGENCY: National Marine Fisheries Service (NMFS), National Oceanic... of importation into the United States and conduct of other transactions (such as export and...

  5. 78 FR 72584 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-03

    ... fisheries, and taking into account the protection of marine ecosystems.'' NMFS' preliminary estimate of... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National..., 2013. Emily H. Menashes, Acting Director, Office of Sustainable Fisheries, National Marine...

  6. 77 FR 28496 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-15

    ..., preserving traditional fisheries, and taking into account the protection of marine ecosystems''. Migration of... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National..., Acting Director, Office of Sustainable Fisheries, National Marine Fisheries Service. BILLING CODE...

  7. 78 FR 20258 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-04

    ... traditional fisheries, and taking into account the protection of marine ecosystems.'' It is important that... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... Fisheries, National Marine Fisheries Service. BILLING CODE 3510-22-P...

  8. 78 FR 50346 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-19

    ..., preserving traditional fisheries, and taking into account the protection of marine ecosystems.'' Commercial... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National..., Acting Deputy Director, Office of Sustainable Fisheries, National Marine Fisheries Service. BILLING...

  9. 78 FR 77362 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-23

    ... taking into account the protection of marine ecosystems.'' For the last two years, the available January... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... Sustainable Fisheries, National Marine Fisheries Service. BILLING CODE 3510-22-P...

  10. 76 FR 76900 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-09

    ... opportunities, preserving traditional fisheries, and taking into account the protection of marine ecosystems... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... Director, Office of Sustainable Fisheries, National Marine Fisheries Service. BILLING CODE 3510-22-P...

  11. 77 FR 53150 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-31

    ... fisheries, and taking into account the protection of marine ecosystems.'' Commercial-sized BFT migrated to... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... Fullenkamp, Acting Deputy Director, Office of Sustainable Fisheries, National Marine Fisheries...

  12. An evaluation of mercury concentrations in three brands of canned tuna.

    PubMed

    Gerstenberger, Shawn L; Martinson, Adam; Kramer, Joanna L

    2010-02-01

    There is widespread concern over the presence of Hg in fish consumed by humans. While studies have been focused on determining the Hg concentration in sport fish and some commercial fish, little attention has been directed to canned tuna; it is widely held that concentrations are low. In the present study, the amount of Hg present in canned tuna purchased in Las Vegas, Nevada, USA, was examined, and the brand, temporal variation, type, and packaging medium impacts on Hg concentrations in tuna were explored. A significant (p < 0.001) brand difference was noted: Brand 3 contained higher Hg concentrations ($\\bar x$ standard deviation (SD) (0.777 +/- 0.320 ppm) than Brands 1 (0.541 +/- 0.114 ppm) and 2 (0.550 +/- 0.199 ppm). Chunk white tuna (0.619 +/- 0.212 ppm) and solid white tuna (0.576 +/- 0.178 ppm) were both significantly (p < 0.001) higher in mean Hg than chunk light tuna (0.137 +/- 0.063 ppm). No significant temporal variation was noted, and packaging had no significant effect on Hg concentration. In total, 55% of all tuna examined was above the U.S. Environmental Protection Agency's (U.S. EPA) safety level for human consumption (0.5 ppm), and 5% of the tuna exceeded the action level established by the U.S. Food and Drug Administration (U.S. FDA) (1.0 ppm). These results indicate that stricter regulation of the canned tuna industry is necessary to ensure the safety of sensitive populations such as pregnant women, infants, and children. According to the U.S. EPA reference dose of 0.1 microg/kg body weight per day and a mean Hg value of 0.619 ppm, a 25-kg child may consume a meal (75 g) of canned chunk white tuna only once every 18.6 d. Continued monitoring of the industry and efforts to reduce Hg concentrations in canned tuna are recommended. Environ.

  13. El Nino Southern Oscillation (ENSO) impact on tuna fisheries in Indian Ocean.

    PubMed

    Kumar, Palanisamy Satheesh; Pillai, Gopalakrishna N; Manjusha, Ushadevi

    2014-01-01

    El Nino Southern Oscillation (ENSO) is an important driver of interannual variations in climate and ecosystem productivity in tropical regions. However, detailed information about this important phenomenon of the Indian Ocean is scarce. Consequently, the objective of this study is to improve understanding of the impact of warm event El Nino and cool event La Nina on annual tuna landings from the Indian Ocean from 1980 to 2010. In this study, maximum tuna landings were recorded during a weak El Nino year (1456054 t in 2006) and during a weak La Nina year (1243562 t in 2000), although the lowest tuna catch was followed during the strong El Nino year (1204119 t in 2009) and during a strong La Nina year (706546 t in 1988). Validation of predicted tuna landings and SST were showing a significant positive correlation (p < 0.01) was observed all the major tuna species except Southern Bluefin Tuna. Whereas the other relationships such as sea level pressure, Wind actions; Zonal Wind (U), Meridonial Wind (V), and Scalar Wind (W) are less well-defined. In contrast with principal component analysis we find that Principal Components 1 explains 75.5% of the total variance and suggest that sea surface temperature plays a major role in determining tuna availability in the region especially during warm event El Nino years; landings in Indian Ocean tend to be optimum SST 25 to 26°C in ENSO event. Our results confirm the ENSO impact on climate, tuna abundance and production in the Indian Ocean. However, among the oceanic variables SST explained the highest deviance in generalized additive models and therefore considered the best habitat predictor in the Indian Ocean followed by sea level pressure and Winds (U, V, W).

  14. Species-diverse coral communities on an artificial substrate at a tuna farm in Amami, Japan.

    PubMed

    Hata, Hiroki; Hirabayashi, Isao; Hamaoka, Hideki; Mukai, Yoshio; Omori, Koji; Fukami, Hironobu

    2013-04-01

    Tuna-farming is expanding worldwide, necessitating the monitoring/managing of its effects on the natural environment. In Japan, tuna-farming is conducted on coral reefs that have been damaged by mass-bleaching events and crown-of-thorns starfish (COTS) outbreaks. This study focused on the coral community on an artificial substrate of tuna-farm to reveal the possible effects of tuna-farming on the natural environment. Corals flourished on ropes suspended in the farm in the Amami Islands, southern Japan. These were moored 3 m below the sea-surface in 50-m-deep water. The coral community on the rope was analyzed and compared with those on natural substrata on two adjacent COTS-damaged reefs and with that in a protected reef. Corals were monitored throughout a year. Sixty coral species grew on the ropes, that corresponds to 27.3% of the 220 species known from Amami. The coral community was unique, dominated by massive faviid corals. On the ropes, the water temperature rarely exceeded 30.0 °C and no corals on the rope were severely bleached or covered by sedimentation during the observations. The tuna-farm infrastructure provided corals with a suitable habitat, and species-rich coral communities were established. These coral communities are an important node connecting tuna-farms and the natural environment.

  15. Characterization of the Boundary Layer on Full-Scale Bluefin Tuna

    NASA Astrophysics Data System (ADS)

    Amaral, Brian; Cipolla, Kimberly; Henoch, Charles

    2014-11-01

    The physics that enable tuna to cross large expanses of ocean while feeding and avoiding predators is not presently understood, and could involve complex control of turbulent boundary layer transition and drag reduction. Typical swimming speeds of Bluefin tuna are 1-2 m/s, but can be higher during strong accelerations. The goal of this work is to experimentally determine the approximate lateral location at which transition to turbulence occurs on the tuna for various speeds. The question is whether laminar flow or an advanced propulsion mechanism (or both) allows them to swim at high speeds. Uncertainties include the surface roughness of the skin, local favorable and adverse pressure gradients, and discontinuities such as the open mouth or juncture at the fins. Historically, much of the fluid mechanics work in the area of fish locomotion has focused on vortex shedding issues rather than the boundary layer. Here, the focus is obtaining information on the boundary layer characteristics of a rigid tuna model. A full scale model of a Pacific Bluefin tuna was fabricated using a mold made from an actual deceased tuna, preserving the surface features and details of the appendages. The model was instrumented with 32 wall pressure sensors and experiments performed in a tow tank. Results from flow visualization, drag and wall pressure measurements over a range of speeds and varying angles of attack will be presented.

  16. Heavy metals in canned tuna from Italian markets.

    PubMed

    Russo, R; Lo Voi, A; De Simone, A; Serpe, F P; Anastasio, A; Pepe, T; Cacace, D; Severino, L

    2013-02-01

    Fish is a good source of nutrients for humans but can pose a risk to human health because of the possible presence of some xenobiotics such as heavy metals and persistent organic contaminants. Constant monitoring is needed to minimize health risks and ensure product quality and consumer safety. The aim of the present study was to use atomic absorption spectrometry to determine the concentrations of some heavy metals (Hg, Pb, and Cd) in tuna packaged in different kinds of packages (cans or glass) in various countries (Italy and elsewhere). Concentrations of Cd and Hg were within the limits set by European Commission Regulation (EC) No 1881/2006 and in many samples were below the detection limit. Pb concentrations exceeded European limits in 9.8% of the analyzed samples. These results are reassuring in terms of food safety but highlighted the need to constantly monitor the concentrations of heavy metals in fish products that could endanger consumer health.

  17. Simulating energy flow in biomolecules: application to tuna cytochrome c.

    PubMed Central

    Wang, Q; Wong, C F; Rabitz, H

    1998-01-01

    By constructing a continuity equation of energy flow, one can utilize results from a molecular dynamics simulation to calculate the energy flux or flow in different parts of a biomolecule. Such calculations can yield useful insights into the pathways of energy flow in biomolecules. The method was first tested on a small system of a cluster of 13 argon atoms and then applied to the study of the pathways of energy flow after a tuna ferrocytochrome c molecule was oxidized. Initially, energy propagated faster along the direction perpendicular to the heme plane. This was due to an efficient through-bond mechanism, because the heme iron in cytochrome c was covalently bonded to a cysteine and a histidine. For the oxidation of cytochrome c, electrostatic interactions also facilitated a long-range through-space mechanism of energy flow. As a result, polar or charged groups that were further away from the oxidation site could receive energy earlier than nonpolar groups closer to the site. Another bridging mechanism facilitating efficient long-range responses to cytochrome c oxidation involved the coupling of far-off atoms with atoms that were nearer to, and interacted directly with, the oxidation site. The different characteristics of these energy transfer mechanisms defied a simple correlation between the time that the excess energy of the oxidation site first dissipated to an atom and the distance of the atom from the oxidation site. For tuna cytochrome c, all of the atoms of the protein had sensed the effects of the oxidation within approximately 40 fs. For the length scale of energy transfer considered in this study, the speed of the energy propagation in the protein was on the order of 10(5) m/s. PMID:9649368

  18. Modelling the Spatial Behaviour of a Tropical Tuna Purse Seine Fleet

    PubMed Central

    Davies, Tim K.; Mees, Chris C.; Milner-Gulland, E. J.

    2014-01-01

    Industrial tuna fisheries operate in the Indian, Atlantic and Pacific Oceans, but concerns over sustainability and environmental impacts of these fisheries have resulted in increased scrutiny of how they are managed. An important but often overlooked factor in the success or failure of tuna fisheries management is the behaviour of fishers and fishing fleets. Uncertainty in how a fishing fleet will respond to management or other influences can be reduced by anticipating fleet behaviour, although to date there has been little research directed at understanding and anticipating the human dimension of tuna fisheries. The aim of this study was to address gaps in knowledge of the behaviour of tuna fleets, using the Indian Ocean tropical tuna purse seine fishery as a case study. We use statistical modelling to examine the factors that influence the spatial behaviour of the purse seine fleet at broad spatiotemporal scales. This analysis reveals very high consistency between years in the use of seasonal fishing grounds by the fleet, as well as a forcing influence of biophysical ocean conditions on the distribution of fishing effort. These findings suggest strong inertia in the spatial behaviour of the fleet, which has important implications for predicting the response of the fleet to natural events or management measures (e.g., spatial closures). PMID:25462165

  19. Modelling the spatial behaviour of a tropical tuna purse seine fleet.

    PubMed

    Davies, Tim K; Mees, Chris C; Milner-Gulland, E J

    2014-01-01

    Industrial tuna fisheries operate in the Indian, Atlantic and Pacific Oceans, but concerns over sustainability and environmental impacts of these fisheries have resulted in increased scrutiny of how they are managed. An important but often overlooked factor in the success or failure of tuna fisheries management is the behaviour of fishers and fishing fleets. Uncertainty in how a fishing fleet will respond to management or other influences can be reduced by anticipating fleet behaviour, although to date there has been little research directed at understanding and anticipating the human dimension of tuna fisheries. The aim of this study was to address gaps in knowledge of the behaviour of tuna fleets, using the Indian Ocean tropical tuna purse seine fishery as a case study. We use statistical modelling to examine the factors that influence the spatial behaviour of the purse seine fleet at broad spatiotemporal scales. This analysis reveals very high consistency between years in the use of seasonal fishing grounds by the fleet, as well as a forcing influence of biophysical ocean conditions on the distribution of fishing effort. These findings suggest strong inertia in the spatial behaviour of the fleet, which has important implications for predicting the response of the fleet to natural events or management measures (e.g., spatial closures).

  20. Inshore capture-based tuna aquaculture impact on Posidonia oceanica meadows in the eastern part of the Adriatic Sea.

    PubMed

    Kružić, Petar; Vojvodić, Vjeročka; Bura-Nakić, Elvira

    2014-09-15

    Mapping and monitoring of the seagrass Posidonia oceanica in the eastern (Croatian) part of the Adriatic Sea since 2004 indicates a significant decline in meadow density in an area impacted by inshore capture-based tuna aquaculture. The density and overall condition of P. oceanica meadows impacted by tuna farms near Fulija Islet was compared to two reference sites (Iž Island and Mrtovnjak Islet). The factors with the most significant influence on P. oceanica meadows were found to be the input of organic matter originating from the cages, as well as high epiphyte biomass caused by nutrient enrichment. Significant differences in nutrient concentrations were found between the sites impacted by tuna farms (Fulija Islet) and the control stations. Shoot density of the P. oceanica meadows decreased at the stations in close vicinity to the tuna farm, which suggests that the tuna farm activity strongly affected the surrounding meadows.

  1. Modeling the Spatial Dynamics of International Tuna Fleets.

    PubMed

    Sun, Jenny; Hinton, Michael G; Webster, D G

    2016-01-01

    We developed an iterative sequential random utility model to investigate the social and environmental determinants of the spatiotemporal decision process of tuna purse-seine fishery fishing effort in the eastern Pacific Ocean. Operations of the fishing gear mark checkpoints in a continuous complex decision-making process. Individual fisher behavior is modeled by identifying diversified choices over decision-space for an entire fishing trip, which allows inclusion of prior and current vessel locations and conditions among the explanatory variables. Among these factors are vessel capacity; departure and arrival port; duration of the fishing trip; daily and cumulative distance travelled, which provides a proxy for operation costs; expected revenue; oceanographic conditions; and tons of fish on board. The model uses a two-step decision process to capture the probability of a vessel choosing a specific fishing region for the first set and the probability of switching to (or staying in) a specific region to fish before returning to its landing port. The model provides a means to anticipate the success of marine resource management, and it can be used to evaluate fleet diversity in fisher behavior, the impact of climate variability, and the stability and resilience of complex coupled human and natural systems.

  2. Application of transfer functions to canned tuna fish thermal processing.

    PubMed

    Ansorena, M R; del Valle, C; Salvadori, V O

    2010-02-01

    Design and optimization of thermal processing of foods need accurate dynamic models to ensure safe and high quality food products. Transfer functions had been demonstrated to be a useful tool to predict thermal histories, especially under variable operating conditions. This work presents the development and experimental validation of a dynamic model (discrete transfer function) for the thermal processing of tuna fish in steam retorts. Transfer function coefficients were obtained numerically, using commercial software of finite elements (COMSOL Multiphysics) to solve the heat transfer balance. Dependence of transfer function coefficients on the characteristic dimensions of cylindrical containers (diameter and height) and on the sampling interval is reported. A simple equation, with two empirical parameters that depends on the container dimensions, represented the behavior of transfer function coefficients with very high accuracy. Experimental runs with different size containers and different external conditions (constant and variable retort temperature) were carried out to validate the developed methodology. Performance of the thermal process simulation was tested for predicting internal product temperature of the cold point and lethality and very satisfactory results were found. The developed methodology can play an important role in reducing the computational effort while guaranteeing accuracy by simplifying the calculus involved in the solution of heat balances with variable external conditions and emerges as a potential approach to the implementation of new food control strategies leading not only to more efficient processes but also to product quality and safety.

  3. Reproductive Schedules in Southern Bluefin Tuna: Are Current Assumptions Appropriate?

    PubMed Central

    Evans, Karen; Patterson, Toby A.; Reid, Howard; Harley, Shelton J.

    2012-01-01

    Southern bluefin tuna (SBT) appear to comprise a single stock that is assumed to be both mixed across its distribution and having reproductive adults that are obligate, annual spawners. The putative annual migration cycle of mature SBT consists of dispersed foraging at temperate latitudes with migration to a single spawning ground in the tropical eastern Indian Ocean. Spawning migrations have been assumed to target two peaks in spawning activity; one in September-October and a second in February-March. SBT of sizes comparable to that of individuals observed on the spawning ground were satellite tagged in the Tasman Sea region (2003–2008) and demonstrated both migrations to the spawning grounds and residency in the Tasman Sea region throughout the whole year. All individuals undertaking apparent spawning migrations timed their movements to coincide with the second recognised spawning peak or even later. These observations suggest that SBT may demonstrate substantial flexibility in the scheduling of reproductive events and may even not spawn annually as currently assumed. Further, the population on the spawning grounds may be temporally structured in association with foraging regions. These findings provide new perspectives on bluefin population and spatial dynamics and warrant further investigation and consideration of reproductive schedules in this species. PMID:22514636

  4. Modeling the Spatial Dynamics of International Tuna Fleets

    PubMed Central

    2016-01-01

    We developed an iterative sequential random utility model to investigate the social and environmental determinants of the spatiotemporal decision process of tuna purse-seine fishery fishing effort in the eastern Pacific Ocean. Operations of the fishing gear mark checkpoints in a continuous complex decision-making process. Individual fisher behavior is modeled by identifying diversified choices over decision-space for an entire fishing trip, which allows inclusion of prior and current vessel locations and conditions among the explanatory variables. Among these factors are vessel capacity; departure and arrival port; duration of the fishing trip; daily and cumulative distance travelled, which provides a proxy for operation costs; expected revenue; oceanographic conditions; and tons of fish on board. The model uses a two-step decision process to capture the probability of a vessel choosing a specific fishing region for the first set and the probability of switching to (or staying in) a specific region to fish before returning to its landing port. The model provides a means to anticipate the success of marine resource management, and it can be used to evaluate fleet diversity in fisher behavior, the impact of climate variability, and the stability and resilience of complex coupled human and natural systems. PMID:27537545

  5. Reproductive schedules in southern bluefin tuna: are current assumptions appropriate?

    PubMed

    Evans, Karen; Patterson, Toby A; Reid, Howard; Harley, Shelton J

    2012-01-01

    Southern bluefin tuna (SBT) appear to comprise a single stock that is assumed to be both mixed across its distribution and having reproductive adults that are obligate, annual spawners. The putative annual migration cycle of mature SBT consists of dispersed foraging at temperate latitudes with migration to a single spawning ground in the tropical eastern Indian Ocean. Spawning migrations have been assumed to target two peaks in spawning activity; one in September-October and a second in February-March. SBT of sizes comparable to that of individuals observed on the spawning ground were satellite tagged in the Tasman Sea region (2003-2008) and demonstrated both migrations to the spawning grounds and residency in the Tasman Sea region throughout the whole year. All individuals undertaking apparent spawning migrations timed their movements to coincide with the second recognised spawning peak or even later. These observations suggest that SBT may demonstrate substantial flexibility in the scheduling of reproductive events and may even not spawn annually as currently assumed. Further, the population on the spawning grounds may be temporally structured in association with foraging regions. These findings provide new perspectives on bluefin population and spatial dynamics and warrant further investigation and consideration of reproductive schedules in this species.

  6. Adaptive responses of tropical tuna purse-seiners under temporal regulations.

    PubMed

    Torres-Irineo, Edgar; Dreyfus-León, Michel; Gaertner, Daniel; Salas, Silvia; Marchal, Paul

    2017-02-01

    The failure to achieve fisheries management objectives has been broadly discussed in international meetings. Measuring the effects of fishery regulations is difficult due to the lack of detailed information. The yellowfin tuna fishery in the eastern Pacific Ocean offers an opportunity to evaluate the fishers' responses to temporal regulations. We used data from observers on-board Mexican purse-seine fleet, which is the main fleet fishing on dolphin-associated tuna schools. In 2002, the Inter-American Tropical Tuna Commission implemented a closed season to reduce fishing effort for this fishery. For the period 1992-2008, we analysed three fishery indicators using generalized estimating equations to evaluate the fishers' response to the closure. We found that purse-seiners decreased their time spent in port, increased their fishing sets, and maintained their proportion of successful fishing sets. Our results highlight the relevance of accounting for the fisher behaviour to understand fisheries dynamics when establishing management regulations.

  7. US Food and Drug Administration survey of methyl mercury in canned tuna

    SciTech Connect

    Yess, J.

    1993-01-01

    Methyl mercury was determined by the US Food and Drug Administration (FDA) in 220 samples of canned tuna collected in 1991. Samples were chosen to represent different styles, colors, and packs as available. Emphasis was placed on water-packed tuna, small can size, and the highest-volume brand names. The average methyl mercury (expressed as Hg) found for the 220 samples was 0.17 ppm; the range was <0.10-0.75 ppm. Statistically, a significantly higher level of methyl mercury was found in solid white and chunk tuna. Methyl mercury level was not related to can size. None of the 220 samples had methyl mercury levels that exceeded the 1 ppm FDA action level. 11 refs., 1 tab.

  8. Performance variation due to stiffness in a tuna-inspired flexible foil model.

    PubMed

    Rosic, Mariel-Luisa N; Thornycroft, Patrick J M; Feilich, Kara L; Lucas, Kelsey N; Lauder, George V

    2017-01-17

    Tuna are fast, economical swimmers in part due to their stiff, high aspect ratio caudal fins and streamlined bodies. Previous studies using passive caudal fin models have suggested that while high aspect ratio tail shapes such as a tuna's generally perform well, tail performance cannot be determined from shape alone. In this study, we analyzed the swimming performance of tuna-tail-shaped hydrofoils of a wide range of stiffnesses, heave amplitudes, and frequencies to determine how stiffness and kinematics affect multiple swimming performance parameters for a single foil shape. We then compared the foil models' kinematics with published data from a live swimming tuna to determine how well the hydrofoil models could mimic fish kinematics. Foil kinematics over a wide range of motion programs generally showed a minimum lateral displacement at the narrowest part of the foil, and, immediately anterior to that, a local area of large lateral body displacement. These two kinematic patterns may enhance thrust in foils of intermediate stiffness. Stiffness and kinematics exhibited subtle interacting effects on hydrodynamic efficiency, with no one stiffness maximizing both thrust and efficiency. Foils of intermediate stiffnesses typically had the greatest coefficients of thrust at the highest heave amplitudes and frequencies. The comparison of foil kinematics with tuna kinematics showed that tuna motion is better approximated by a zero angle of attack foil motion program than by programs that do not incorporate pitch. These results indicate that open questions in biomechanics may be well served by foil models, given appropriate choice of model characteristics and control programs. Accurate replication of biological movements will require refinement of motion control programs and physical models, including the creation of models of variable stiffness.

  9. Characterization of the Boundary Layers on Full-Scale Bluefin Tuna

    DTIC Science & Technology

    2014-09-30

    Although the typical swimming speeds of bluefin tuna are 1 – 2 m/s, they can be higher during strong accelerations. The goal of the work...speeds. The question is whether laminar flow or an advanced propulsion mechanism (or both) allows them to swim at high speeds. A full-scale model...and drag reduction on the body. The typical swimming speed of bluefin tuna is 1 – 2 m/s, but it can be higher during strong accelerations. The

  10. Interaction between Coastal and Oceanic Ecosystems of the Western and Central Pacific Ocean through Predator-Prey Relationship Studies

    PubMed Central

    Allain, Valerie; Fernandez, Emilie; Hoyle, Simon D.; Caillot, Sylvain; Jurado-Molina, Jesus; Andréfouët, Serge; Nicol, Simon J.

    2012-01-01

    The Western and Central Pacific Ocean sustains the highest tuna production in the world. This province is also characterized by many islands and a complex bathymetry that induces specific current circulation patterns with the potential to create a high degree of interaction between coastal and oceanic ecosystems. Based on a large dataset of oceanic predator stomach contents, our study used generalized linear models to explore the coastal-oceanic system interaction by analyzing predator-prey relationship. We show that reef organisms are a frequent prey of oceanic predators. Predator species such as albacore (Thunnus alalunga) and yellowfin tuna (Thunnus albacares) frequently consume reef prey with higher probability of consumption closer to land and in the western part of the Pacific Ocean. For surface-caught-predators consuming reef prey, this prey type represents about one third of the diet of predators smaller than 50 cm. The proportion decreases with increasing fish size. For predators caught at depth and consuming reef prey, the proportion varies with predator species but generally represents less than 10%. The annual consumption of reef prey by the yellowfin tuna population was estimated at 0.8±0.40CV million tonnes or 2.17×1012±0.40CV individuals. This represents 6.1%±0.17CV in weight of their diet. Our analyses identify some of the patterns of coastal-oceanic ecosystem interactions at a large scale and provides an estimate of annual consumption of reef prey by oceanic predators. PMID:22615796

  11. 75 FR 51182 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    ... Atlantic bluefin tuna (BFT) retention limit should be adjusted from one to three large medium or giant BFT... medium and giant BFT over a range of zero to a maximum of three per vessel based on consideration of the....9 mt, and increased the default General category daily retention limit of one large medium or...

  12. Examining dolphin hydrodynamics provides clues to calf-loss during tuna fishing

    PubMed Central

    Moore, Pete

    2004-01-01

    A combination of mathematical modeling and direct observation of the swimming behavior of dolphin mother-calf pairs has shown how the calf can gain much of the energy required for swimming if it is positioned correctly relative to the mother, a situation that may be disrupted during the chases that result from tuna-fishing practices. PMID:15132739

  13. 77 FR 24669 - Atlantic Highly Migratory Species; Public Conference Call Regarding Recreational Yellowfin Tuna...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-25

    ... Species; Public Conference Call Regarding Recreational Yellowfin Tuna Fishery Data Collection AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce... conference call that is open to the public will be held to discuss historical and future data collection...

  14. Gender Transformations and Colonial Displacements in Laura Antillano's "Tuna de mar"

    ERIC Educational Resources Information Center

    Reid, Alana

    2015-01-01

    This paper examines the trajectories of two characters in Laura Antillano's short story, "Tuna de mar" (1991), as they navigate interrelated systems of power and attempt to position themselves closer to, or further away from, the margins. Set in the late eighteenth century, the tale features a female protagonist who escapes prostitution…

  15. Determination of histamine in canned tuna by molecularly imprinted polymers-surface enhanced Raman spectroscopy.

    PubMed

    Gao, Fang; Grant, Edward; Lu, Xiaonan

    2015-12-11

    We introduce a rapid, cost effective and reliable approach to determine histamine level in canned tuna. Molecularly imprinted polymers (MIPs) were synthesized as artificial antibodies towards histamine by utilizing the interaction between histamine and a functional monomer (methacrylic acid) to impress specific binding sites on polymer particles after polymerization. Polyvinyl chloride (PVC) was used to immobilize the MIPs, yielding a MIPs-PVC film that functioned as a recognition element to specifically separate histamine from tuna extract. A gold colloid solution served both as an eluting solvent to extract histamine from MIPs-PVC film and furnish a substrate for surface enhanced Raman spectroscopy (SERS) detection of histamine signals. Principal component analysis together with a partial least square regression (PLSR) model (R(2) = 0.947, RMSECV = 3.526) verified the reliability of MIPs-PVC-SERS approach for the detection and spectral analysis of histamine. Linear regression models were also constructed to relate the intensity of different histamine SERS bands with the corresponding spiking levels. One such model (using a band at 1576 cm(-1)) performed slightly better in predicting histamine content in tuna than the PLSR model. We conclude that our new MIPs-PVC-SERS approach can rapidly and reliably determine histamine at levels from 3 to 90 ppm in canned tuna meat.

  16. Reproductive biology of yellowfin tuna T. albacares in the west-central Indian Ocean

    NASA Astrophysics Data System (ADS)

    Zhu, Guoping; Xu, Liuxiong; Zhou, Yingqi; Song, Liming

    2008-08-01

    Survey of yellowfin tuna in the west-central Indian Ocean was conducted on board of Chinese longliners during 2003, 2004 and 2005, which is a part of Chinese Tuna Fishery Scientific Observer Program (CTFSOP). The reproductive biology has been investigated. A total of 1 023 samples are collected including 417 ovaries and 606 testes. Spawning activities of yellowfin tuna have been studied for both male and female from January to June. The data showed that the average monthly sex ratio is 0.59, and the minimum length at sexual maturity is 101 cm for female and 110 cm for male respectively. Length at 50% sexual maturity is estimated at 113.77 cm for female and 120.20 cm for male, whereas maturation rate is 0.066 cm-1 for female and 0.091 cm-1 for male. Sex ratio by length class indicates that the proportion of male is higher than female’s along with size increasing; for instance, in the group of the body length longer than 145 cm, some females have their body length from 145 to 160 cm and males have their body length at 160 cm and even longer. Statistically, yellowfin tuna has a significant seasonal reproduction.

  17. 77 FR 38011 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-26

    ... National Oceanic and Atmospheric Administration 50 CFR Part 635 RIN 0648-XC055 Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... closes the incidental Longline category northern area fishery for large medium and giant Atlantic...

  18. 75 FR 33731 - Atlantic Highly Migratory Species; 2010 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 50 CFR Part 635 RIN 0648-AY77 Atlantic Highly Migratory Species; 2010 Atlantic Bluefin Tuna Quota Specifications Correction In rule document 2010-13207...

  19. Probing local thermal stabilities of bovine, horse, and tuna ferricytochromes c at pH 7.

    PubMed

    Filosa, A; English, A M

    2000-08-01

    Correlation between the flexibility of the Met80 loop (residues 75-86) and the local stabilities of native ferricytochromes c from horse, bovine, and tuna was examined. By monitoring the heme bands versus temperature, absorption changes associated with altered ligation in the alkaline isomers were observed. In addition, the intensity of the 695-nm absorption band, which is associated with the heme-crevice stability, decreased with increasing temperature and exhibited biphasic temperature dependence, with transition temperatures (Tc) at 35 degrees C in tuna c, 55 degrees C in horse c, and 58 C in bovine c. Since the heme crevice plays a key role in the thermal stabilities of cytochromes c, their susceptibility to proteolytic attack was examined as a function of temperature. Proteolytic digestion, which requires local conformational instability, revealed that the local stabilities of the cytochromes follow the order: bovine > horse > tuna, and increased digestion occurred at temperatures close to the 695-nm Tc for each protein. This is consistent with the actual substitution of the Met80 ligand above the 695-nm Tc, which is reflected in the thermodynamic parameters for the two phases. Also, tuna c, unlike horse and bovine c, exhibits different 695-nm (35 degrees C) and Soret (approximately 46 degrees C) Tc values, but its local stability is controlled by the transition detected at 695 nm. The combined spectroscopic and proteolysis results clearly indicate that the flexibility of the Met80 loop determines the local stability of cytochromes c.

  20. 75 FR 30732 - Atlantic Highly Migratory Species; 2010 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-02

    ... Atlantic Tunas Convention Act (ATCA), and to achieve domestic management objectives under the Magnuson... contracting parties and other domestic management objectives, if warranted; and (3) provide the non-Longline..., the effects of the adjustment on accomplishing the objectives of the fishery management plan,...

  1. 77 FR 74612 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-17

    ... taking into account the protection of marine ecosystems.'' Under the two-fish limit that applied in... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... Director, Office of Sustainable Fisheries, National Marine Fisheries Service. BILLING CODE 3510-22-P...

  2. 78 FR 26709 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-08

    ... Species; Atlantic Bluefin Tuna Fisheries AGENCY: National Marine Fisheries Service (NMFS), National... recreational opportunities, preserving traditional fisheries, and taking into account the protection of marine ecosystems.'' Migration of commercial-size BFT to the fishing grounds off the northeast U.S. coast...

  3. 50 CFR 635.24 - Commercial retention limits for sharks, swordfish, and BAYS tunas.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... storage of silky sharks, oceanic whitetip sharks, and scalloped, smooth, and great hammerhead sharks is... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Commercial retention limits for sharks... Management Measures § 635.24 Commercial retention limits for sharks, swordfish, and BAYS tunas. The...

  4. 50 CFR 635.24 - Commercial retention limits for sharks, swordfish, and BAYS tunas.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... storage of silky sharks, oceanic whitetip sharks, and scalloped, smooth, and great hammerhead sharks is... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Commercial retention limits for sharks... Management Measures § 635.24 Commercial retention limits for sharks, swordfish, and BAYS tunas. The...

  5. 50 CFR 600.15 - Other acronyms.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... management terms. (1) ABC—acceptable biological catch (2) ATCA-Atlantic Tunas Convention Act (3) BFT (Atlantic bluefin tuna) means the subspecies of bluefin tuna, Thunnus thynnus thynnus, or a part thereof, that occurs in the Atlantic Ocean. (4) BSD means the ICCAT bluefin tuna statistical document. (5)...

  6. Comparative ecology of widely distributed pelagic fish species in the North Atlantic: Implications for modelling climate and fisheries impacts

    NASA Astrophysics Data System (ADS)

    Trenkel, V. M.; Huse, G.; MacKenzie, B. R.; Alvarez, P.; Arrizabalaga, H.; Castonguay, M.; Goñi, N.; Grégoire, F.; Hátún, H.; Jansen, T.; Jacobsen, J. A.; Lehodey, P.; Lutcavage, M.; Mariani, P.; Melvin, G. D.; Neilson, J. D.; Nøttestad, L.; Óskarsson, G. J.; Payne, M. R.; Richardson, D. E.; Senina, I.; Speirs, D. C.

    2014-12-01

    This paper reviews the current knowledge on the ecology of widely distributed pelagic fish stocks in the North Atlantic basin with emphasis on their role in the food web and the factors determining their relationship with the environment. We consider herring (Clupea harengus), mackerel (Scomber scombrus), capelin (Mallotus villosus), blue whiting (Micromesistius poutassou), and horse mackerel (Trachurus trachurus), which have distributions extending beyond the continental shelf and predominantly occur on both sides of the North Atlantic. We also include albacore (Thunnus alalunga), bluefin tuna (Thunnus thynnus), swordfish (Xiphias gladius), and blue marlin (Makaira nigricans), which, by contrast, show large-scale migrations at the basin scale. We focus on the links between life history processes and the environment, horizontal and vertical distribution, spatial structure and trophic role. Many of these species carry out extensive migrations from spawning grounds to nursery and feeding areas. Large oceanographic features such as the North Atlantic subpolar gyre play an important role in determining spatial distributions and driving variations in stock size. Given the large biomasses of especially the smaller species considered here, these stocks can exert significant top-down pressures on the food web and are important in supporting higher trophic levels. The review reveals commonalities and differences between the ecology of widely distributed pelagic fish in the NE and NW Atlantic basins, identifies knowledge gaps and modelling needs that the EURO-BASIN project attempts to address.

  7. A comparative study of thermal calcination and an alkaline hydrolysis method in the isolation of hydroxyapatite from Thunnus obesus bone.

    PubMed

    Venkatesan, Jayachandran; Qian, Zhong Ji; Ryu, BoMi; Thomas, Noel Vinay; Kim, Se Kwon

    2011-06-01

    In the present study, hydroxyapatite (HAp) was isolated from Thunnus obesus bone using alkaline hydrolysis and thermal calcination methods. The obtained ceramic has been characterized by thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), powder x-ray diffraction analysis (XRD), field-emission scanning electron microscopy, energy-dispersive x-ray analysis, transmission electron microscopy (TEM), selected area diffraction analysis, cytotoxic analysis and cell proliferation analysis. The results indicate that there are significant differences between the ceramics and T. obesus bone. FT-IR and TGA results affirmed that the collagen and organic moieties have been eliminated by both the proposed methods. XRD results were in agreement with JCPDS data. TEM and selective area diffraction images have signified that the thermal calcination method produces good crystallinity with dimensions 0.3-1.0 µm, whereas the alkaline hydrolysis method produces nanostructured HAp crystals with 17-71 nm length and 5-10 nm width. Biocompatibility of HAp crystals was evaluated by cytotoxicity and cell proliferation with human osteoblast-like cell MG-63.

  8. Detecting the presence-absence of bluefin tuna by automated analysis of medium-range sonars on fishing vessels.

    PubMed

    Uranga, Jon; Arrizabalaga, Haritz; Boyra, Guillermo; Hernandez, Maria Carmen; Goñi, Nicolas; Arregui, Igor; Fernandes, Jose A; Yurramendi, Yosu; Santiago, Josu

    2017-01-01

    This study presents a methodology for the automated analysis of commercial medium-range sonar signals for detecting presence/absence of bluefin tuna (Tunnus thynnus) in the Bay of Biscay. The approach uses image processing techniques to analyze sonar screenshots. For each sonar image we extracted measurable regions and analyzed their characteristics. Scientific data was used to classify each region into a class ("tuna" or "no-tuna") and build a dataset to train and evaluate classification models by using supervised learning. The methodology performed well when validated with commercial sonar screenshots, and has the potential to automatically analyze high volumes of data at a low cost. This represents a first milestone towards the development of acoustic, fishery-independent indices of abundance for bluefin tuna in the Bay of Biscay. Future research lines and additional alternatives to inform stock assessments are also discussed.

  9. Canned bluefin tuna, an in vitro cardioprotective functional food potentially safer than commercial fish oil based pharmaceutical formulations.

    PubMed

    Tenore, Gian Carlo; Calabrese, Giorgio; Ritieni, Alberto; Campiglia, Pietro; Giannetti, Daniela; Novellino, Ettore

    2014-09-01

    Commercial canned fish species typical in the Italian market were evaluated for their lipid profile. Bluefin tuna samples showed the highest content in omega-3 fatty acids (n-3 PUFA) among the canned fish samples analyzed. Tests on H9C2 cardiomyocytes revealed that bluefin tuna n-3 PUFA may responsible for a significant cell protection against both physiological and doxorubicin-induced oxidative stress. Analogous tests performed by incubating cardiac cells with n-3 PUFA ethyl esters, of which most of fish oil pharmaceutical formulations (FOPF) are based, showed cytotoxicity at high doses. Our results highlighted that n-3 PUFA contents in a 50 g canned bluefin tuna portion would be almost equivalent to and potentially safer than those of 1 FOPF capsule (1000 mg)/die usually suggested for hyperlipidaemic subjects. Thus, Italian commercial canned bluefin tuna could be indicated as a functional food with potential health benefits for the prevention and care of cardiovascular disorders.

  10. Oligonucleotide indexing of DNA barcodes: identification of tuna and other scombrid species in food products

    PubMed Central

    2010-01-01

    Background DNA barcodes are a global standard for species identification and have countless applications in the medical, forensic and alimentary fields, but few barcoding methods work efficiently in samples in which DNA is degraded, e.g. foods and archival specimens. This limits the choice of target regions harbouring a sufficient number of diagnostic polymorphisms. The method described here uses existing PCR and sequencing methodologies to detect mitochondrial DNA polymorphisms in complex matrices such as foods. The reported application allowed the discrimination among 17 fish species of the Scombridae family with high commercial interest such as mackerels, bonitos and tunas which are often present in processed seafood. The approach can be easily upgraded with the release of new genetic diversity information to increase the range of detected species. Results Cocktail of primers are designed for PCR using publicly available sequences of the target sequence. They are composed of a fixed 5' region and of variable 3' cocktail portions that allow amplification of any member of a group of species of interest. The population of short amplicons is directly sequenced and indexed using primers containing a longer 5' region and the non polymorphic portion of the cocktail portion. A 226 bp region of CytB was selected as target after collection and screening of 148 online sequences; 85 SNPs were found, of which 75 were present in at least two sequences. Primers were also designed for two shorter sub-fragments that could be amplified from highly degraded samples. The test was used on 103 samples of seafood (canned tuna and scomber, tuna salad, tuna sauce) and could successfully detect the presence of different or additional species that were not identified on the labelling of canned tuna, tuna salad and sauce samples. Conclusions The described method is largely independent of the degree of degradation of DNA source and can thus be applied to processed seafood. Moreover, the

  11. 77 FR 59842 - Atlantic Highly Migratory Species; 2006 Consolidated Highly Migratory Species Fishery Management...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ...) permit, which allows fishing for and sale of bigeye, albacore, yellowfin, and skipjack (BAYS) tunas...: Atlantic tunas and swordfish are managed under the dual authority of the Magnuson-Stevens Fishery Conservation and Management Act (Magnuson-Stevens Act) and the Atlantic Tuna Conventions Act (ATCA),...

  12. 76 FR 37750 - Atlantic Highly Migratory Species; Electronic Dealer Reporting Requirements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-28

    ... swordfish, shark, and tunas dealers report commercially harvested Atlantic sharks, swordfish, and bigeye, albacore, yellowfin, and skipjack (BAYS) tunas to NMFS through an electronic reporting system. At this time, Atlantic Highly Migratory Species (HMS) dealers would not be required to report bluefin tuna through...

  13. The aggregation of tuna around floating objects: what could be the underlying social mechanisms?

    PubMed

    Robert, Marianne; Dagorn, Laurent; Deneubourg, Jean Louis

    2014-10-21

    Several empirical and theoretical studies have shown how the exploitation of food sources, the choice of resting sites or other types of collective decision-making in heterogeneous environments are facilitated and modulated by social interactions between conspecifics. It is well known that many pelagic fishes live in schools and that this form of gregarious behavior provides advantages in terms of food intake and predator avoidance efficiency. However, the influence of social behavior in the formation of aggregations by tuna under floating objects (FOBs) is poorly understood. In this work, we investigated the collective patterns generated by different theoretical models, which either include or exclude social interactions between conspecifics, in the presence of two aggregation sites. The resulting temporal dynamics and distributions of populations were compared to in situ observations of tuna behavior. Our work suggests that social interactions should be incorporated in aggregative behavior to reproduce the temporal patterns observed in the field at both the individual and the group level, challenging the common vision of tuna aggregations around FOBs. Our study argues for additional data to further demonstrate the role of social behavior in the dynamics of these fish aggregations. Understanding the interplay between environmental and social factors in the associative behavior of fish with FOBs is necessary to assess the consequences of the widespread deployment of artificial FOBs by fishermen.

  14. Prediction of Quality Change During Thawing of Frozen Tuna Meat by Numerical Calculation I

    NASA Astrophysics Data System (ADS)

    Murakami, Natsumi; Watanabe, Manabu; Suzuki, Toru

    A numerical calculation method has been developed to determine the optimum thawing method for minimizing the increase of metmyoglobin content (metMb%) as an indicator of color changes in frozen tuna meat during thawing. The calculation method is configured the following two steps: a) calculation of temperature history in each part of frozen tuna meat during thawing by control volume method under the assumption of one-dimensional heat transfer, and b) calculation of metMb% based on the combination of calculated temperature history, Arrenius equation and the first-order reaction equation for the increase rate of metMb%. Thawing experiments for measuring temperature history of frozen tuna meat were carried out under the conditions of rapid thawing and slow thawing to compare the experimental data with calculated temperature history as well as the increase of metMb%. The results were coincident with the experimental data. The proposed simulation method would be useful for predicting the optimum thawing conditions in terms of metMb%.

  15. Comparative influence of ocean conditions on yellowfin and Atlantic bluefin tuna catch from longlines in the Gulf of Mexico.

    PubMed

    Teo, Steven L H; Block, Barbara A

    2010-05-28

    Directed fishing effort for Atlantic bluefin tuna in the Gulf of Mexico (GOM), their primary spawning grounds in the western Atlantic, has been prohibited since the 1980s due to a precipitous decline of the spawning stock biomass. However, pelagic longlines targeted at other species, primarily yellowfin tuna and swordfish, continue to catch Atlantic bluefin tuna in the GOM as bycatch. Spatial and temporal management measures minimizing bluefin tuna bycatch in the GOM will likely become important in rebuilding the western Atlantic bluefin stock. In order to help inform management policy and understand the relative distribution of target and bycatch species in the GOM, we compared the spatiotemporal variability and environmental influences on the catch per unit effort (CPUE) of yellowfin (target) and bluefin tuna (bycatch). Catch and effort data from pelagic longline fisheries observers (1993-2005) and scientific tagging cruises (1998-2002) were coupled with environmental and biological data. Negative binomial models were used to fit the data for both species and Akaike's Information Criterion (corrected for small sample size) was used to determine the best model. Our results indicate that bluefin CPUE had higher spatiotemporal variability as compared to yellowfin CPUE. Bluefin CPUE increased substantially during the breeding months (March-June) and peaked in April and May, while yellowfin CPUE remained relatively high throughout the year. In addition, bluefin CPUE was significantly higher in areas with negative sea surface height anomalies and cooler sea surface temperatures, which are characteristic of mesoscale cyclonic eddies. In contrast, yellowfin CPUE was less sensitive to environmental variability. These differences in seasonal variability and sensitivity to environmental influences suggest that bluefin tuna bycatch in the GOM can be reduced substantially by managing the spatial and temporal distribution of the pelagic longline effort without substantially

  16. The efficacy of X-ray does on murine norovirus-1 (MNV-1) in pure culture, half-shell oyster, salmon sushi, and tuna salad

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this investigation, we determined the efficacy of X-ray doses on reducing a human norovirus (HuNoV) surrogate [murine norovirus-1 (MNV-1)] in pure culture, half-shell oyster, salmon sushi and tuna salad. The pure culture (phosphate-buffer saline, pH 7.4), half-shell oyster, salmon sushi and tuna ...

  17. Remote sensing and the pelagic fisheries environment off Oregon

    NASA Technical Reports Server (NTRS)

    Pearcy, W. G.

    1970-01-01

    Remote sensing oceanography at Oregon State University is part of a multidisciplinary research program: (1) to learn more about nearshore oceanographic processes and how they affect the production of marine life and the availability of albacore tuna; and (2) to provide fishermen with information in near real time that will be useful in scouting for albacore concentrations.

  18. 76 FR 17380 - Submission for OMB Review; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-29

    ... Administration (NOAA). Title: U.S.-Canada Albacore Treaty Reporting System. OMB Control Number: 0648-0492. Form... Region (SWR), manages the United States (U.S.)-Canada Albacore Tuna Treaty of 1981 (Treaty). Owners of... their desire to be on the list of vessels provided to Canada each year indicating vessels eligible...

  19. Habitat overlap between southern bluefin tuna and yellowfin tuna in the east coast longline fishery - implications for present and future spatial management

    NASA Astrophysics Data System (ADS)

    Hartog, Jason R.; Hobday, Alistair J.; Matear, Richard; Feng, Ming

    2011-03-01

    Southern bluefin tuna (SBT) are presently a quota-managed species in the multi-species eastern Australian tuna and billfish longline fishery (ETBF). Capture of SBT is regulated by quota, as is access to regions likely to contain SBT. A habitat prediction model combining data from an ocean model and pop-up satellite archival tags is used to define habitat zones based on the probability of SBT occurrence. These habitat zones are used by fishery managers to restrict access by ETBF fishers to SBT habitat during a May-November management season. The zones display a distinct seasonal cycle driven by the seasonal southward expansion and northward contraction of the East Australia Current (EAC) and as a result access by fishers to particular ocean regions changes seasonally. This species also overlaps with the commercially valuable yellowfin tuna (YFT), thus, we modified the SBT model to generate YFT habitat predictions in order to investigate habitat overlap between SBT and YFT. There is seasonal variation in the overlap of the core habitat between these two species, with overlap early (May-Jul) in the management season and habitat separation occurring towards the end (Aug-Nov). The EAC is one of the fastest warming ocean regions in the southern hemisphere. To consider the future change in distribution of these two species compared to the present and to explore the potential impact on fishers and managers of the future, we use future ocean predictions from the CSIRO Bluelink ocean model for the year 2064 to generate habitat predictions. As the ocean warms on the east coast of Australia and the EAC extends southward, our model predicts the suitable habitat for SBT and YFT will move further south. There was an increase in the overlap of SBT and YFT habitat throughout the management season, due to regional variation of each species' habitat. These results illustrate that a management tradeoff exists between restricting fisher access to SBT habitat and allowing access to YFT

  20. Polychlorinated biphenyls and organochlorine pesticides as intrinsic tracer tags of foraging grounds of bluefin tuna in the northwest Atlantic Ocean.

    PubMed

    Deshpande, Ashok D; Dickhut, Rebecca M; Dockum, Bruce W; Brill, Richard W; Farrington, Cameron

    2016-04-15

    Researchers have utilized chemical fingerprints in the determination of habitat utilization and movements of the aquatic animals. In the present effort, we analyzed polychlorinated biphenyl (PCB) congeners and organochlorine pesticides in the samples of juvenile bluefin tuna caught offshore of Virginia, and in larger bluefin tuna from the Gulf of Maine and near Nova Scotia. For a given specimen, or a given location, PCB concentrations were highest, followed by DDTs, and chlordanes. Average contaminant concentrations from fish captured from the three locations were not significantly different; and PCBs, DDTs, and chlordanes correlated well with each other. Trans-nonachlor/PCB 153 ratios in bluefin tuna of eastern Atlantic (i.e., Mediterranean) origin are low compared to the corresponding ratios in fish in the western Atlantic. As the former migrate to the western Atlantic, these ratios gradually turnover due to the accumulation of biomass from forage contaminated with higher trans-nonachlor/PCB 153 ratio reflecting dissimilar use of chlordane pesticides on two sides of the Atlantic Ocean. The trans-nonachlor/PCB 153 ratio indicated that one juvenile bluefin tuna from offshore of Virginia and one large bluefin tuna from Gulf of Maine in the present study originated from foraging grounds in the Mediterranean Sea, and that they have made the trans-Atlantic migrations. The remaining individuals were determined to be either spawned in the Gulf of Mexico or the trans-nonachlor/PCB 153 ratio for the putative Mediterranean bluefin tuna was completely turned over to resemble the ratio characteristic to the western Atlantic. Based on the turnover time for trans-nonachlor/PCB 153 ratio previously determined, the residence time of juvenile bluefin tuna offshore Virginia was estimated to be at least 0.8 to 1.6years. A discriminant function analysis (DFA) plot of total PCB normalized signatures of PCB congeners showed three separate clusters, which suggested that bluefin tuna

  1. Anti-wrinkle effects of a tuna heart H2O fraction on Hs27 human fibroblasts

    PubMed Central

    KIM, YOUNG-MIN; JUNG, HEE-JIN; CHOI, JAE-SUE; NAM, TAEK-JEONG

    2016-01-01

    With the increase in life expectancy, there is also growing interest in anti-aging treatments and technologies. The development of anti-aging functional drugs for the skin, and foods from natural sources, may offer solutions to this global matter. Aging involves structural, functional and biochemical changes that occur throughout cells and bodily tissues; the amount of hormones secreted from of all human organs, including the skin, decreases over time. Matrix metalloproteinase (MMP) genes (MMP-1 and -8) play an important role in the aging of skin fibroblasts. For example, an increased MMP expression causes accelerated aging and the degradation of skin elasticity-related genes. In the present study, we examined the anti-wrinkle effects of tuna heart extract which are mediated through the inhibition of MMPs in skin cells. Generally, tuna contains high concentrations of selenium and antioxidants, which serve to remove free radicals, and is known to delay skin and body aging. In addition, unsaturated fatty acids in tuna help to maintain the natural glossy look of skin, and increase skin elasticity, providing moisture for dry skin. A recent study confirmed the various bio-effects of boiled tuna extract and muscle. However, bioactivity studies using tuna heart are limited. Thus, in the present study, we obtained extracts and fractions of tuna heart, and examined their effects on Hs27 human fibroblast proliferation using an MTS assay. In addition, we measured procollagen type 1 levels and elastase activity, and performed β-galactosidase staining. We then measured the expression levels of phosphatidylinositol 3-kinase/Akt and MMP-related genes by western blot analysis and RT-PCR. Our results revealed that tuna heart extract decreased MMP expression by upregulating tissue inhibitors of metallopro-teinase-1 (TIMP-1) and decreasing elastase activity, thus exerting anti-aging and anti-wrinkle effects by increasing collagen synthesis and promoting skin fibroblast proliferation

  2. Encapsulation of mixtures of tuna oil, tributyrin and resveratrol in a spray dried powder formulation.

    PubMed

    Sanguansri, Luz; Day, Li; Shen, Zhiping; Fagan, Peter; Weerakkody, Rangika; Cheng, Li Jiang; Rusli, Jenny; Augustin, Mary Ann

    2013-12-01

    Spray dried emulsions are effective for carrying and stabilising combinations of fish oil and tributyrin, fish oil and resveratrol, or fish oil, tributyrin and resveratrol in one formulation. The encapsulation efficiencies were >99% for all three bioactives when a heated mixture of sodium caseinate: glucose: dried glucose syrup matrix (Encapsulant matrix 1) was used. When a heated sodium caseinate: glucose: processed starch matrix (Encapsulant matrix 2) was used, the encapsulation efficiencies were 90-92% for tributyrin and approximately 98% for resveratrol for all formulations but 79-91% for tuna oil where the efficiency was more formulation dependent. There was 84-86% remaining EPA, 85-87% remaining DHA, 85% remaining tributyrin and 94-96% remaining resveratrol after 18 months at 25 °C storage of the spray dried emulsions using Encapsulant matrix 1 across all formulations. In comparison, there was 83-87% remaining EPA and 84-89% remaining DHA, 80-82% remaining tributyrin, and 81-100% remaining resveratrol across all formulations with Encapsulant matrix 2. In vitro studies showed that on sequential exposure to simulated gastric and intestinal fluids, <5% tuna oil was found as triglycerides, but all the tributyrin had been lipolysed. The presence of diglycerides, monoglycerides and free fatty acids in the in vitro digests suggested that lipolysis of tuna oil had occurred. The type of matrix used for encapsulating the bioactives had little effect on the lipolysis of the oils but affected the amount of solvent extractable resveratrol. The ability of delivering mixtures of bioactives within one formulation was demonstrated.

  3. The Conservation and Management of Tunas and Their Relatives: Setting Life History Research Priorities

    PubMed Central

    Juan-Jordá, Maria José; Mosqueira, Iago; Freire, Juan; Dulvy, Nicholas K.

    2013-01-01

    Scombrids (tunas, bonitos, Spanish mackerels and mackerels) support important fisheries in tropical, subtropical and temperate waters around the world, being one of the most economically- and socially-important marine species globally. Their sustainable exploitation, management and conservation depend on accurate life history information for the development of quantitative fisheries stock assessments, and in the fishery data-poor situations for the identification of vulnerable species. Here, we assemble life history traits (maximum size, growth, longevity, maturity, fecundity, spawning duration and spawning interval) for the 51 species of scombrids globally. We identify major biological gaps in knowledge and prioritize life history research needs in scombrids based on their biological gaps in knowledge, the importance of their fisheries and their current conservation status according to the International Union for Conservation of Nature Red List. We find that the growth and reproductive biology of tunas and mackerel species have been more extensively studied than for Spanish mackerels and bonitos, although there are notable exceptions in all groups. We also reveal that reproductive biology of species, particular fecundity, is the least studied biological aspect in scombrids. We identify two priority groups, including 32 species of scombrids, and several populations of principal market tunas, for which life history research should be prioritized following the species-specific life history gaps identified in this study in the coming decades. By highlighting the important gaps in biological knowledge and providing a priority setting for life history research in scombrid species this study provides guidance for management and conservation and serves as a guide for biologists and resource managers interested in the biology, ecology, and management of scombrid species. PMID:23950930

  4. The conservation and management of tunas and their relatives: setting life history research priorities.

    PubMed

    Juan-Jordá, Maria José; Mosqueira, Iago; Freire, Juan; Dulvy, Nicholas K

    2013-01-01

    Scombrids (tunas, bonitos, Spanish mackerels and mackerels) support important fisheries in tropical, subtropical and temperate waters around the world, being one of the most economically- and socially-important marine species globally. Their sustainable exploitation, management and conservation depend on accurate life history information for the development of quantitative fisheries stock assessments, and in the fishery data-poor situations for the identification of vulnerable species. Here, we assemble life history traits (maximum size, growth, longevity, maturity, fecundity, spawning duration and spawning interval) for the 51 species of scombrids globally. We identify major biological gaps in knowledge and prioritize life history research needs in scombrids based on their biological gaps in knowledge, the importance of their fisheries and their current conservation status according to the International Union for Conservation of Nature Red List. We find that the growth and reproductive biology of tunas and mackerel species have been more extensively studied than for Spanish mackerels and bonitos, although there are notable exceptions in all groups. We also reveal that reproductive biology of species, particular fecundity, is the least studied biological aspect in scombrids. We identify two priority groups, including 32 species of scombrids, and several populations of principal market tunas, for which life history research should be prioritized following the species-specific life history gaps identified in this study in the coming decades. By highlighting the important gaps in biological knowledge and providing a priority setting for life history research in scombrid species this study provides guidance for management and conservation and serves as a guide for biologists and resource managers interested in the biology, ecology, and management of scombrid species.

  5. 77 FR 51709 - International Fisheries; Western and Central Pacific Fisheries for Highly Migratory Species...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-27

    ...; Western and Central Pacific Fisheries for Highly Migratory Species; Bigeye Tuna Catch Limit in Longline... rule establishes a catch limit of 3,763 metric tons (mt) of bigeye tuna (Thunnus obesus) for vessels in..., retaining, transshipping, or landing bigeye tuna caught in the WCPO will be prohibited for the remainder...

  6. Global pollution monitoring of polybrominated diphenyl ethers using skipjack tuna as a bioindicator.

    PubMed

    Ueno, Daisuke; Kajiwara, Natsuko; Tanaka, Hiroyuki; Subramanian, Annamalai; Fillmann, Gilberto; Lam, Paul K S; Zheng, Gene J; Muchitar, Muswerry; Razak, Hamidah; Prudente, Maricar; Chung, Kyu-Hyuck; Tanabe, Shinsuke

    2004-04-15

    To elucidate the global distribution of polybrominated diphenyl ethers (PBDEs), these chemicals were determined in the muscle of skipjack tuna (Katsuwonus pelamis) collected from offshore waters of various regions in the world (Japan, Taiwan, Philippines, Indonesia, Seychelles, and Brazil, and the Japan Sea, East China Sea, South China Sea, Indian Ocean, and North Pacific Ocean). PBDEs were detected in almost all the skipjack tuna collected from the locations surveyed (from < 0.1 to 53 ng/g of lipid), indicating widespread contamination by these compounds in the marine environment. Residue levels of PBDEs in these samples from the northern hemisphere seem to be higher than those from the southern hemisphere, which is plausibly due to larger usage of these compounds in the northern hemisphere. Higher concentrations of PBDEs were detected in the samples from waters around the East China Sea (up to 53 ng/g of lipid). Developing countries around the East China Sea are supposedly the "hot spots" releasing these chemicals into the marine environment. With regard to the composition of PBDE congeners, the percentage contribution by lower brominated congeners (BDE15, -28, and -47) showed an increasing trend with increasing latitude. On the other hand, higher brominated congeners (BDE153, -154, and -183) showed a reverse trend. These patterns suggest that lower brominated congeners of PBDEs (di-, tri-, and tetra-BDEs) were preferentially transported from pollution sources to northern colder regions through the atmosphere. PBDEs may have a high potency to cause global pollution like PCBs.

  7. Absolute abundance of southern bluefin tuna estimated by close-kin mark-recapture

    PubMed Central

    Bravington, Mark V.; Grewe, Peter M.; Davies, Campbell R.

    2016-01-01

    Southern bluefin tuna is a highly valuable, severely depleted species, whose abundance and productivity have been difficult to assess with conventional fishery data. Here we use large-scale genotyping to look for parent–offspring pairs among 14,000 tissue samples of juvenile and adult tuna collected from the fisheries, finding 45 pairs in total. Using a modified mark-recapture framework where ‘recaptures' are kin rather than individuals, we can estimate adult abundance and other demographic parameters such as survival, without needing to use contentious fishery catch or effort data. Our abundance estimates are substantially higher and more precise than previously thought, indicating a somewhat less-depleted and more productive stock. More broadly, this technique of ‘close-kin mark-recapture' has widespread utility in fisheries and wildlife conservation. It estimates a key parameter for management—the absolute abundance of adults—while avoiding the expense of independent surveys or tag-release programmes, and the interpretational problems of fishery catch rates. PMID:27841264

  8. Organochlorine pesticides in canned tuna and sardines on the Serbian market.

    PubMed

    Kartalović, Brankica; Novakov, Nikolina J; Mihaljev, Željko; Petrović, Jelena; Prica, Nadežda; Babić, Jelena; Ćirković, Miroslav A

    2016-12-01

    The aim of this study was to determine the level of organochlorine (OC) pesticides in 57 samples of canned tuna and 31 samples of canned sardines in vegetable oil, collected from supermarkets in Serbia. OC pesticides α-HCH, β-HCH, δ-HCH, dichlorodiphenyltrichloroethane (DDT), DDE, DDD, dielderin, endosulfane I, endosulfane II, endosulan sulfate, endrin, endrin ketone, heptachlor, heptachlor epoxide, lindane, aldrin, metoxichlor, cis-chlordane and trans-chlordane were determined using a GS-MS method. The highest concentrations (µg kg(-1), arithmetic means) in canned tuna were for δ-HCH (60.6 ± 97.0) and p, p´-DDT (55.0 ± 25.1), while the corresponding values in canned sardines were for δ-HCH (90.7 ± 102.7) and endosulfane II (78.0 ± 145.9). Mean level for the sum of endosulfans was above the maximum limit in canned sardines (85.0 µg kg(-1)). Also, dieldrin (39.7 µg kg(-1)) was measured above the ML.

  9. Population declines of tuna and relatives depend on their speed of life

    PubMed Central

    Juan-Jordá, M. J.; Mosqueira, I.; Freire, J.; Dulvy, N. K.

    2015-01-01

    Larger-bodied species in a wide range of taxonomic groups including mammals, fishes and birds tend to decline more steeply and are at greater risk of extinction. Yet, the diversity in life histories is governed not only by body size, but also by time-related traits. A key question is whether this size-dependency of vulnerability also holds, not just locally, but globally across a wider range of environments. We test the relative importance of size- and time-related life-history traits and fishing mortality in determining population declines and current exploitation status in tunas and their relatives. We use high-quality datasets of half a century of population trajectories combined with population-level fishing mortalities and life-history traits. Time-related traits (e.g. growth rate), rather than size-related traits (e.g. maximum size), better explain the extent and rate of declines and current exploitation status across tuna assemblages, after controlling for fishing mortality. Consequently, there is strong geographical patterning in population declines, such that populations with slower life histories (found at higher cooler latitudes) have declined most and more steeply and have a higher probability of being overfished than populations with faster life histories (found at tropical latitudes). Hence, the strong, temperature-driven, latitudinal gradients in life-history traits may underlie the global patterning of population declines, fisheries collapses and local extinctions. PMID:26156763

  10. Lead, cadmium, arsenic and mercury in canned tuna fish marketed in Tehran, Iran.

    PubMed

    Andayesh, Shirin; Hadiani, Mohammad Rasoul; Mousavi, Zahra; Shoeibi, Shahram

    2015-01-01

    Fifty-four canned tuna fish samples corresponding to 10 widely used different brands were purchased from local markets in Tehran, Iran during 2012-2013 and analysed on heavy metals. Mercury was determined by a direct mercury analyser without any sample preparation. For analysis of other elements samples were digested using a microwave apparatus. Lead and cadmium were determined by graphite furnace atomic absorption spectrometry and arsenic via hydride vapour generation. All samples had arsenic and mercury contamination. Arsenic levels showed a range of 0.25-1.42 mg kg(-1), which might be due to lack of national and international limits for arsenic in canned tuna fish. Lead and cadmium were measured in a small number of samples with a mean of 0.053 ± 0.058 mg kg(-1) and 0.013 ± 0.015 mg kg(-1), respectively. Results obtained for these heavy metals in all samples were lower than the corresponding limits, whereas arsenic and mercury contents might raise some attention.

  11. Microbiological Stability of Canned Tuna Produced in Italy and in Non-European Countries

    PubMed Central

    Gazzotti, Teresa; Rippa, Paola; Ciambrone, Lucia; Musarella, Rosanna; Pratticò, Elena

    2015-01-01

    The results of a study on the microbiological stability of canned tuna produced by Italian companies and similar canned products manufactured in countries outside Europe are reported herein. The study involved 38 samples of canned tuna of various brands, of which 14 were produced by companies outside Europe and 24 by Italian companies. Qualitative and quantitative microbiological tests were conducted for the following parameters: bacterial colony counts at 30°C, total coliforms, total Enterobacteriaceae, sulphite-reducing anaerobes, Salmonella spp., Bacillus cereus, Escherichia coli, Staphylococcus aureus, yeasts and molds. Bacterial loads and mold contamination were respectivelyin found in 8/14 (57%) samples from outside EU and 7/24 (29%) Italian samples. The bacterial flora was represented by Gram-positive bacteria (Staphylococcus warneri, Staphylococcus lentus, Streptococcus mitis, Enterococcus faecalis, Leuconostoc mesenteroides), Gram-negative bacteria (Sphingomonas paucimobilis, Acinetobacter iwoffii, Rhizobium radiobacter), spore-forming bacteria (Bacillus vallismortis), while the fungal species was represented by Penicillium spp., Rhizopus spp., Rhodotorula spp. and Alternaria spp. Excluding anomalies in the thermal treatment process of products and any contamination after treatment, the contaminations encountered in both cases were most likely due to insufficient production quality standards and the quality of the raw material used. These results may require a redefinition of the concept of commercial stability as hitherto stated. PMID:27800383

  12. Heavy metal content and molecular species identification in canned tuna: Insights into human food safety.

    PubMed

    Pappalardo, Anna Maria; Copat, Chiara; Ferrito, Venera; Grasso, Alfina; Ferrante, Margherita

    2017-03-24

    Canned tuna in olive oil and in brine of the most popular brands sold in Italian markets were analyzed to verify the authentication of transformed products, with the aim to unveil commercial frauds due to the substitutions of high value species with species of low commercial value, and to assess the health risk of consumers related to cadmium (Cd), lead (Pb) and mercury (Hg) contents. Species authentication was evaluated with amplification of COI DNA barcode and confirmed the declared species. Among tested metals, Hg had the highest concentrations, followed by Cd and Pb. None of the tested samples surpassed the European regulatory limits no. 1881/2006 fixed for Hg and Pb, whereas one batch of canned tuna in olive oil exceeded standard for Cd. Risk for human health was evaluated by the metals daily intake and target hazard quotient (THQ). As a result, Cd and Pb did not exceed the toxicological reference values established by World Health Organization (WHO) and the Environmental Protection Agency (EPA). Conversely, Hg content suggests a consumption no more than once a week and a continuous surveillance of this fishery products for consumer protection.

  13. 78 FR 40997 - Enhanced Document Requirements To Support Use of the Dolphin Safe Label on Tuna Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-09

    ... harvested (16 U.S.C. 1385(d)(1)(B)(i)). Furthermore, if the Secretary identifies any other fishery that has... favorable treatment to Mexican tuna products and therefore is inconsistent with Article 2.1 of the TBT..., where applicable; (2) the proposed rule will improve verification efforts; (3) the proposed rule...

  14. Proteomic analysis of processing by-products from canned and fresh tuna: identification of potentially functional food proteins.

    PubMed

    Sanmartín, Esther; Arboleya, Juan Carlos; Iloro, Ibon; Escuredo, Kepa; Elortza, Felix; Moreno, F Javier

    2012-09-15

    Proteomic approaches have been used to identify the main proteins present in processing by-products generated by the canning tuna-industry, as well as in by-products derived from filleting of skeletal red muscle of fresh tuna. Following fractionation by using an ammonium sulphate precipitation method, three proteins (tropomyosin, haemoglobin and the stress-shock protein ubiquitin) were identified in the highly heterogeneous and heat-treated material discarded by the canning-industry. Additionally, this fractionation method was successful to obtain tropomyosin of high purity from the heterogeneous starting material. By-products from skeletal red muscle of fresh tuna were efficiently fractionated to sarcoplasmic and myofibrillar fractions, prior to the identification based mainly on the combined searching of the peptide mass fingerprint (MALDI-TOF) and peptide fragment fingerprinting (MALDI LIFT-TOF/TOF) spectra of fifteen bands separated by 1D SDS-PAGE. Thus, the sarcoplasmic fraction contained myoglobin and several enzymes that are essential for efficient energy production, whereas the myofibrillar fraction had important contractile proteins, such as actin, tropomyosin, myosin or an isoform of the enzyme creatine kinase. Application of proteomic technologies has revealed new knowledge on the composition of important by-products from tuna species, enabling a better evaluation of their potential applications.

  15. Much More than Music: The Cultural Importance of "Estudiantinas-Tunas" and Choirs as Informal Adult Music Schools and Communitas

    ERIC Educational Resources Information Center

    Gómez-Ullate, Martín; Belmonte Trujillo, José Carlos

    2016-01-01

    For each person studying music in formal institutions in Spain, there are at least five others learning and performing in "informal" schools and settings. Choirs and "estudiantinas" or "tunas" are two examples of these informal schools found both in Ibero-America and worldwide. Their place in society and their…

  16. Improvement of color and physiological properties of tuna-processing by-product by gamma irradiation

    NASA Astrophysics Data System (ADS)

    Choi, Jong-il; Kim, Hyun-Joo; Kim, Jae-Hun; Song, Beom-Seok; Chun, Byeong-Soo; Ahn, Dong-Hyun; Byun, Myung-Woo; Lee, Ju-Woon

    2009-07-01

    Although the by-products from fishery industry had many nutrients, it is being wasted or only used as bacteria media. In this study, the effect of a gamma irradiation on the cooking drips of Thunnus thynnus (CDT) was investigated to examine the possible use of the cooking drips as a functional material for food and cosmetic composition. Total aerobic bacteria, and yeasts/molds from CDT were detected at the level of 2.79 and 2.58 Log CFU/mL, respectively. But, CDT was efficiently sterilized by a gamma irradiation at a low dose of 1 kGy. The Hunter L* value of the gamma-irradiated ethanol extract of CDT was increased, and the a* and b* values were decreased compared to the non-irradiated extract, showing color improvement. Antioxidant activity of the ethanol extract of CDT was increased by a gamma irradiation depending on the irradiation dose. The increased contents of polyphenolic compounds and proteins in CDT extract by gamma irradiation may be the reason of the increased biological activity. These results suggested that the wasted cooking drips can be successfully used as functional components with gamma irradiation treatment.

  17. Trophic niches of sympatric tropical tuna in the Western Indian Ocean inferred by stable isotopes and neutral fatty acids

    NASA Astrophysics Data System (ADS)

    Sardenne, Fany; Bodin, Nathalie; Chassot, Emmanuel; Amiel, Aurélien; Fouché, Edwin; Degroote, Maxime; Hollanda, Stéphanie; Pethybridge, Heidi; Lebreton, Benoit; Guillou, Gaël; Ménard, Frédéric

    2016-08-01

    This study examined the trophic ecology of three sympatric tropical tuna species (bigeye BET, skipjack SKJ, and yellowfin YFT) sampled in the Western Indian Ocean throughout 2013. Specifically we explored inter-specific resource partitioning and ontogenetic variability using neutral fatty acids and stable isotope analysis of liver and muscle from small (⩽100 cm fork length, FL) and large (>100 cm FL) tuna collected in mixed schools at the surface by purse-seine. Both biochemical tracers were used to calculate trophic niche indices that collectively revealed high potential for resource overlap, especially among small tuna. Resource overlap appeared strongest between BET and YFT, with SKJ tissues having high carbon isotope (δ13C) values (-17 ± 0.3‰), lower nitrogen isotope (δ15N) values (11.4 ± 0.6‰), and higher relative proportion of poly-unsaturated fatty acids (PUFA) than the two other species, indicating a different diet. Size was found to be a strong predictor for most biochemical tracers in the three species with δ13C, δ15N and total lipid content in the liver. In the larger species (YFT and BET), proportions of mono-unsaturated fatty acids typically increased with size, while quantities of PUFA decreased. In addition to ontogenetic variability, trophic markers were shown to vary between sampling area and season: higher lipid reserves and δ15N values, and lower δ13C values occurred during monsoon periods around Seychelles than in the Mozambique Channel (parted from about 1500 km). Our multi-tracer approach reveals the magnitude of potential competitive interactions in mixed tropical tuna schools at both small and large sizes and demonstrates that ontogenetic niche differentiation acts as a major factor of coexistence in tropical tuna.

  18. Quantification of derivatives of bisphenol A diglycidyl ether (BADGE) and novolac glycidyl ether (NOGE) migrated from can coatings into tuna by HPLC/fluorescence and MS detection.

    PubMed

    Berger, U; Oehme, M; Girardin, L

    2001-01-02

    A reversed phase high performance liquid chromatographic method combined with fluorescence and mass spectrometric detection in series is presented for the separation and quantification of bisphenol A diglycidyl ether (BADGE) and novolac glycidyl ether (NOGE) derivatives in extracts from food can coatings, tuna and oil. Fifteen samples of tuna cans bought in four European countries were investigated. Atmospheric pressure chemical ionization mass spectrometry in the positive ion mode (APCI(+)-MS) allowed to tentatively identify BADGE and NOGE related compounds originating from reactions of the glycidyl ethers with bisphenols, phenol, butanol, water and hydrochloric acid. Quantification was based on the external standard method and fluorescence detection. Mass fractions up to 3.7 micrograms/g were found for hydrochlorination products of bisphenol F diglycidyl ether (BFDGE + 2HCl) in tuna. Furthermore, total migration quantities of phenolic ether compounds were estimated. The highest values found were 20 micrograms/g in tuna and 43 micrograms/g in the oil phase.

  19. 78 FR 37790 - In the Matter of: Mario Salinas-Lucio, Inmate Number #61687-279, FCI La Tuna, Federal Corrections...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-24

    ... Tuna, Federal Corrections Institution, Federal Satellite Low, P.O. Box 6000, Anthony, TX 88021. Order..., Federal Satellite Low, P.O. Box 6000, Anthony, TX 88021, and when acting for or on behalf of...

  20. Nitrogen isotopic baselines and implications for estimating foraging habitat and trophic position of yellowfin tuna in the Indian and Pacific Oceans

    NASA Astrophysics Data System (ADS)

    Lorrain, Anne; Graham, Brittany S.; Popp, Brian N.; Allain, Valérie; Olson, Robert J.; Hunt, Brian P. V.; Potier, Michel; Fry, Brian; Galván-Magaña, Felipe; Menkes, Christophe E. R.; Kaehler, Sven; Ménard, Frédéric

    2015-03-01

    Assessment of isotopic compositions at the base of food webs is a prerequisite for using stable isotope analysis to assess foraging locations and trophic positions of marine organisms. Our study represents a unique application of stable-isotope analyses across multiple trophic levels (primary producer, primary consumer and tertiary consumer) and over a large spatial scale in two pelagic marine ecosystems. We found that δ15N values of particulate organic matter (POM), barnacles and phenylalanine from the muscle tissue of yellowfin tuna all showed similar spatial patterns. This consistency suggests that isotopic analysis of any of these can provide a reasonable proxy for isotopic variability at the base of the food web. Secondly, variations in the δ15N values of yellowfin tuna bulk-muscle tissues paralleled the spatial trends observed in all of these isotopic baseline proxies. Variation in isotopic composition at the base of the food web, rather than differences in tuna diet, explained the 11‰ variability observed in the bulk-tissue δ15N values of yellowfin tuna. Evaluating the trophic position of yellowfin tuna using amino-acid isotopic compositions across the western Indian and equatorial Pacific Oceans strongly suggests these tuna occupy similar trophic positions, albeit absolute trophic positions estimated by this method were lower than expected. This study reinforces the importance of considering isotopic baseline variability for diet studies, and provides new insights into methods that can be applied to generate nitrogen isoscapes for worldwide comparisons of top predators in marine ecosystems.

  1. Mercury concentration change in human hair after the ingestion of canned tuna fish

    SciTech Connect

    Inasmasu, T.; Ogo, A.; Yanagawa, M.; Keshino, M.; Hirakoba, A.; Takahashi, K.; Ishinish, N.

    1986-10-01

    The concentration of mercury in the hair of man has been conveniently used as an indicator of environmental exposure to mercury. In particular, studies concerning the relationship between the concentration of mercury in the hair and the dietary intake of mercury have revealed that the amount of fish consumed significantly affects the mercury concentration in the scalp hair. However, the quantitative relationship between the mercury concentration in the hair and the dietary intake of mercury has been scarcely proven. This is because mercury concentration in hair sampled reflects the degree of exposure from diet in the past, and because the dietary measurements of mercury generally depend on individuals remembering accurately or having recorded their intake of fish in the past. In an attempt to elucidate this problem. The authors assessed the mercury concentration in the hair of human subjects who ingested a certain amount of canned tuna fish.

  2. [Fatty acids of the tuna of different fishing areas of the Mexican Pacific, canned in oil and water].

    PubMed

    Castro Gónzalez, M I; Montaño Benavides, S; Pérez-Gil Romo, F

    2001-12-01

    A direct relationship exists between the state of health and the diet, and inside this some components, such as the fatty acids (FA), influence mostly in the prevention of certain illnesses (coronary heart disease, hypertension, rheumatoid arthritis, inflammatory answer, and arterial pressure). One of the main sources of essential FA are the marine products; the tuna is a marine food of wide consumption in Mexico due its readiness and low cost. The objective of this work was to determine the profile of fatty acids (FA) in tuna canned in oil and in water coming from three fishing areas of the Mexican Pacific. There were randomly obtained 7 oil-tuna commercial marks (AA) and 5 water- tuna (AW) coming from the next fishery areas: Baja California Sur (L1), Colima (L2) and Mazatlán (L3). The samples without draining were liquefied and thereafter it was obtained the methyl esters of fatty acids that were analyzed by gas chromatography with a flame ionization detector. In all the areas were identified 20 FA (mg/100 g); three AG omega 3 (EPA, DHA and linolenic) and two omega 6 (linoleic and arachidonic). In the AA of the three areas the most abundant saturated FA were estearric and palmitic acids, the most abundant monounsaturated fatty acid was the cis-vaccenic, followed by the oleic acid. The behavior of those omega 3 in the AA of the three areas were similar: with the less quantity was the linolenic acid (447-755), continued by the EPA (979-1323) and finally high concentrations of DHA (1862-3327). In the AW the DHA was the most abundant fatty acid in all the areas (1086-4456), the most abundant monounsaturated fatty acid was the palmitic (640-3809). It was observed the presence of trans fatty acids in high quantities in AW: linolelaidic (1394-1495) and elaidic (377-1234). The relationship omega 3/omega 6 in the AA was similar in L1 and L2, and lower in L3; in AW was higher in L2 and L3. In conclusion, evident variation exists in the content of FA among areas; it could

  3. Spatial distribution and contamination assessment of heavy metals in urban topsoils from Las Tunas City, Cuba.

    PubMed

    Díaz Rizo, O; Fonticiella Morell, D; Arado López, J O; Borrell Muñoz, J L; D'Alessandro Rodríguez, K; López Pino, N

    2013-07-01

    Concentrations of Cr, Co, Ni, Cu, Zn, Pb and Fe in the topsoils (0-10 cm) from Las Tunas city were measured by X-ray fluorescence analysis. The mean Cr, Co, Ni, Cu, Zn and Pb contents in the urban topsoil samples (97 ± 30, 14 ± 2, 35 ± 36, 94 ± 26, 199 ± 87 and 42 ± 29 mg kg⁻¹ dry weight, respectively) were compared with mean concentrations for other cities around the world with similar population. Cr content in school grounds, parks and residential areas exceed in 20 % the average Cr background level. Highest content for Ni was determined in residential areas, for Zn in market gardens soils and as for Pb, the highest topsoil-background content ratios were observed for market gardens (2.7) and residential areas (2.3). Spatial distribution maps indicated the same behaviour for Cr-Co-Ni and Pb-Zn, respectively, whereas the spatial distribution of Cu differs from other heavy metals. On the other hand, the metal-to-iron normalisation, using (10-20 cm) bottom soil contents as background, showed that topsoils in Las Tunas city are severely enriched with lead and not enriched with the rest of the determined metals. The average values of integrated pollution index (IPI) indicated that soils are moderately contaminated by heavy metals (1.17 ≤ IPI(ave) ≤ 1.39), but enrichment index values shows that metal concentrations on the studied locations are not above the permissible levels for urban agriculture.

  4. Isotope dilution SPME GC/MS for the determination of methylmercury in tuna fish samples.

    PubMed

    Centineo, Giuseppe; Blanco González, Elisa; García Alonso, J Ignacio; Sanz-Medel, Alfredo

    2006-01-01

    The development of a rapid, precise and accurate analytical method for the determination of methylmercury in tuna fish samples is described. The method is based on the use of isotope dilution GC/MS with electron impact ionization, a widespread technique in routine testing laboratories. A certified spike containing (202)Hg-enriched methylmercury was used for the isotope dilution of the samples. After extraction of the methylmercury from the sample, methylmercury was propylated using sodium tetrapropyl borate in SPME vials and the analytes were sampled from the headspace for 15 min. For isotope measurements, the molecular ion (MePrHg(+)) was used in the SIM mode. Five molecular ions were monitored, corresponding to the (198)Hg, (199)Hg, (200)Hg, (201)Hg and (202)Hg isotopes. The detection at masses corresponding to (198)Hg was used to correct for m + 1 contributions of (13)C from the organic groups attached to the mercury atom on the (199)Hg, (200)Hg, (201)Hg and (202)Hg masses with simple mathematical equations, and the concentration of methylmercury was calculated on the basis of the corrected (200)Hg/(202)Hg isotope ratio. The (202)Hg-enriched methylmercury spike was applied, with satisfactory results, to the determination of methylmercury in the certified reference material BCR 464. The method was successfully applied to the determination of methylmercury in tuna fish samples, and the obtained results were included in the CCQM-P39 interlaboratory exercise, organized by the Institute for Reference Materials and Measurements (IRMM, Geel, Belgium) with excellent agreement between our results and the average obtained by the other participants.

  5. Trade-offs among catch, bycatch, and landed value in the American Samoa longline fishery.

    PubMed

    Watson, Jordan T; Bigelow, Keith A

    2014-08-01

    The interspecific preferences of fishes for different depths and habitats suggest fishers could avoid unwanted catches of some species while still effectively targeting other species. In pelagic longline fisheries, albacore (Thunnus alalunga) are often caught in relatively cooler, deeper water (>100 m) than many species of conservation concern (e.g., sea turtles, billfishes, and some sharks) that are caught in shallower water (<100 m). From 2007 to 2011, we examined the depth distributions of hooks for 1154 longline sets (3,406,946 hooks) and recorded captures by hook position on 2642 sets (7,829,498 hooks) in the American Samoa longline fishery. Twenty-three percent of hooks had a settled depth <100 m. Individuals captured in the 3 shallowest hook positions accounted for 18.3% of all bycatch. We analyzed hypothetical impacts for 25 of the most abundant species caught in the fishery by eliminating the 3 shallowest hook positions under scenarios with and without redistribution of these hooks to deeper depths. Distributions varied by species: 45.5% (n = 10) of green sea turtle (Chelonia mydas), 59.5% (n = 626) of shortbill spearfish (Tetrapturus angustirostris), 37.3% (n = 435) of silky shark (Carcharhinus falciformis), and 42.6% (n = 150) of oceanic whitetip shark (C. longimanus) were caught on the 3 shallowest hooks. Eleven percent (n = 20,435) of all tuna and 8.5% (n = 10,374) of albacore were caught on the 3 shallowest hooks. Hook elimination reduced landed value by 1.6-9.2%, and redistribution of hooks increased average annual landed value relative to the status quo by 5-11.7%. Based on these scenarios, redistribution of hooks to deeper depths may provide an economically feasible modification to longline gear that could substantially reduce bycatch for a suite of vulnerable species. Our results suggest that this method may be applicable to deep-set pelagic longline fisheries worldwide.

  6. 76 FR 65155 - Fisheries Off West Coast States; Highly Migratory Species Fisheries; Swordfish Retention Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ... States; Highly Migratory Species Fisheries; Swordfish Retention Limits AGENCY: National Marine Fisheries... FMP to incorporate recommended international measures to end overfishing of the Pacific stock of bigeye tuna, Thunnus obesus, in response to formal notification from NMFS that overfishing was...

  7. Detecting the presence-absence of bluefin tuna by automated analysis of medium-range sonars on fishing vessels

    PubMed Central

    Uranga, Jon; Arrizabalaga, Haritz; Boyra, Guillermo; Hernandez, Maria Carmen; Goñi, Nicolas; Arregui, Igor; Fernandes, Jose A.; Yurramendi, Yosu; Santiago, Josu

    2017-01-01

    This study presents a methodology for the automated analysis of commercial medium-range sonar signals for detecting presence/absence of bluefin tuna (Tunnus thynnus) in the Bay of Biscay. The approach uses image processing techniques to analyze sonar screenshots. For each sonar image we extracted measurable regions and analyzed their characteristics. Scientific data was used to classify each region into a class (“tuna” or “no-tuna”) and build a dataset to train and evaluate classification models by using supervised learning. The methodology performed well when validated with commercial sonar screenshots, and has the potential to automatically analyze high volumes of data at a low cost. This represents a first milestone towards the development of acoustic, fishery-independent indices of abundance for bluefin tuna in the Bay of Biscay. Future research lines and additional alternatives to inform stock assessments are also discussed. PMID:28152032

  8. Activity Concentrations and Dose Assessment of Gamma Emitting Radionuclides in Canned Tuna and Sardines Produced after the Fukushima Nuclear Accident.

    PubMed

    Ababneh, Zaid Q; Al-Masoud, Fahad I; Ababneh, Anas M

    2016-01-01

    The aim of the present work was to investigate the radioactivity concentrations of gamma emitting radionuclides in canned tuna and sardines that were produced after the Fukushima nuclear accident and to assess the resulting radiation doses to the public. Fifty-eight brands of canned tuna and sardines consumed in the Middle East and produced from different parts of the world were analyzed using a germanium detector. Cesium-137 (137Cs) was not detected above the minimum detectable activity in any of the samples. Natural radionuclides 40K, 226Ra and 228Ra were detected with wide activity concentration ranges and with average values of (in Bq kg(-1) wet weight): 68 ± 36, 0.31 ± 0.45, 0.34 ± 0.25, respectively, in tuna samples and with averages of 129 ± 67, 0.20 ± 0.33, 0.60 ± 0.31 in sardine samples. The results of the activity concentrations of 40K and 226Ra showed some regional dependence. Tuna samples produced in Europe have almost twice the concentration of 40K and half the concentration of 226Ra as compared to samples produced in either East or South Asia and North America. Moreover, sardine samples produced in North Africa and Europe have almost twice the concentrations of 40K and 226Ra as those produced in East or South Asia and North America. Dose assessment due to ingestion of canned seafood was also performed, and the committed effective dose was found to be well within the worldwide average.

  9. Isolation of heat-tolerant myoglobin from Asian swamp eel Monopterus albus.

    PubMed

    Chotichayapong, Chatrachatchaya; Wiengsamut, Kittipong; Chanthai, Saksit; Sattayasai, Nison; Tamiya, Toru; Kanzawa, Nobuyuki; Tsuchiya, Takahide

    2012-10-01

    Myoglobin from Asian swamp eel Monopterus albus was purified from fish muscle using salt fractionation followed by column chromatography and molecular filtration. The purified Mb of 0.68 mg/g wet weight of muscle was determined for its molecular mass by MALDI-TOF-MS to be 15,525.18 Da. Using isoelectric focusing technique, the purified Mb showed two derivatives with pI of 6.40 and 7.12. Six peptide fragments of this protein identified by LC-MS/MS were homologous to Mbs of sea raven Hemitripterus americanus, yellowfin tuna Thunnus albacores, blue marlin Makaira nigicans, common carp Cyprinus carpio, and goldfish Carassius auratus. According to the Mb denaturation, the swamp eel Mb had thermal stability higher than walking catfish Clarias batrachus Mb and striped catfish Pangasius hypophthalmus Mb, between 30 and 60 (°)C. For the thermal stability of Mb, the swamp eel Mb showed a biphasic behavior due to the O(2) dissociation and the heme orientation disorder, with the lowest increase in both Kd(f) and Kd(s). The thermal sensitivity of swamp eel Mb was lower than those of the other Mbs for both of fast and slow reaction stages. These results suggest that the swamp eel Mb globin structure is thermally stable, which is consistent with heat-tolerant behavior of the swamp eel particularly in drought habitat.

  10. Climate change projection for the western tropical Pacific Ocean using a high-resolution ocean model: Implications for tuna fisheries

    NASA Astrophysics Data System (ADS)

    Matear, R. J.; Chamberlain, M. A.; Sun, C.; Feng, M.

    2015-03-01

    The Western Pacific Warm Pool is a region of high tuna catch, and how future climate change might impact the tuna fisheries is an important regional issue. By using a high-resolution ocean model forced by the simulated climate of the 2060s, we investigate whether enhanced spatial resolution and bias correction of the mean state could alter the climate change projection for the western tropical Pacific and examine the consequences this might have for tropical tuna distributions. For most of the physical environmental variables, enhanced resolution and bias correction had only a minor impact on the projected changes. The climate projections showed a maximum surface warming east of the Warm Pool, a shoaling of the thermocline in the Warm Pool, and an eastward expansion of the Warm Pool. In the Warm Pool, the shoaling of the thermocline raises the nutricline into the photic zone and increases phytoplankton and primary productivity, a feature that is most evident in the high-resolution model projection but also weakly present in the coarse-resolution projection. The phytoplankton and primary productivity response to climate change was where ocean model resolution produced a clear difference. With enhanced resolution, the simulation had stronger and better-defined zonal currents, which were more consistent with observations. Along the equator, the high-resolution model enabled vertical current shear mixing to generate a sub-surface phytoplankton maximum both inside and outside the Warm Pool, which is an observed phenomenon. With climate change, the enhanced-resolution model projected enhanced vertical shear mixing, increased vertical supply of nutrients to the photic zone, and increased sub-surface phytoplankton concentrations. The increase in sub-surface phytoplankton concentrations helps to offset the decline in surface phytoplankton concentrations and results in a projection of almost no change in the western tropical Pacific primary productivity. In contrast, the low

  11. Vascular anatomy of the gills in a high energy demand teleost, the skipjack tuna (Katsuwonus pelamis).

    PubMed

    Olson, Kenneth R; Dewar, Heidi; Graham, Jeffrey B; Brill, Richard W

    2003-05-01

    Tunas (family: Scombridae, Tribe: Thunnini) exhibit anatomical, physiological, and biochemical adaptations that dramatically increase the ability of their cardiorespiratory systems to transfer oxygen from the water to the tissues. In the present study the vascular anatomy of the skipjack tuna, Katsuwonus pelamis, gill was examined by light and scanning electron microscopic analysis of methyl methacrylate vascular corrosion replicas prepared under physiological pressure. The gill filament contains three distinct blood pathways, respiratory, interlamellar, and nutrient. The respiratory, or arterio-arterial (AA) pathway, is the site of gas exchange and consists of the afferent and efferent filamental arteries (AFA and EFA) and arterioles (ALA and ELA) and the lamellae. Each ALA in the basal filament supplies ten or more lamellae and they anastomose with their neighbor to form a continuous vascular arcade. Four modifications in the lamellar circulation appear to enhance gas exchange efficiency. 1) The ALA deliver blood directly to the outer margin of the lamellae where unstirred boundary layer effects are predicted to be minimal and water PO2 highest. 2) Pillar cells are closely aligned along the outer boundary of the inlet side and the inner boundary of the outlet side of the lamellae to form multiple distributing and receiving blood channels. 3) Elsewhere in the lamella, pillar cells are aligned to form diagonal channels that direct blood from the outer to the inner lamellar margins, thereby reducing vascular resistance. 4) The lamellar sinusoid is especially widened near the efferent end to augment oxygen saturation of blood flowing through the inner margin. These adaptations, plus the presence of a bow-shaped interlamellar septum, and a thinned filament core appear to decrease gill vascular resistance and maximize gas-exchange efficiency. The interlamellar (IL) and nutrient systems originate from post-lamellar vessels and are arterio-venous (AV) pathways. IL

  12. Analysis of Metmyoglobin Formation Rates in Frozen Tuna Meat during Frozen Storage

    NASA Astrophysics Data System (ADS)

    Viriyarattanasak, Chotika; Watanabe, Manabu; Suzuki, Toru

    Formation of metmyoglobin (metMb) in frozen tuna meat stored at -90, -60, -40, -30, -20, and -10°C for approximately 6 months was investigated. The reaction rate of metMB formation was estimated from a linear plot of ln ([M∞ . Mt] /[M∞ . Mo]) and storage time (t) for each storage temperature (Ts) (M∞, Mt, and Mo are metMb contents at times t = t∞, t, and 0, respectively). When M∞ was assumed to be 100%, the rate of metMb formation followed the first-order reaction only during the early stage of storage period. MetMb formation, however obeyed the first-order reaction for all test temperatures even during long-term storage when M∞ was assumed to be dependent on storage temperature (M∞(Ts)). A discontinuity was observed in the temperature dependence of M∞(Ts) at storage temperature range between -60 and -40°C, which was attributed to the glass transition of protein system. On the other hand, the temperature dependence of metMb formation did not show a significant change over all storage temperatures.

  13. No evidence for homeoviscous adaptation in a heterothermic tissue: tuna heat exchangers.

    PubMed

    Fudge, D S; Stevens, E D; Ballantyne, J S

    1998-09-01

    Many poikilotherms are known to adjust the membrane composition of their cells in response to a temperature change so that membrane fluidity, and therefore function, is conserved. Such compensatory changes in membrane composition are considered "homeoviscous adaptations." In this study, we examined a heterothermic tissue, the visceral rete mirabile of the bluefin tuna, for evidence of homeoviscous adaptation. We measured the proportions of phospholipid fatty acids and phospholipid head groups as a function of position along the rete thermal gradient, which has been estimated to be approximately 10 degrees C. We found no effect of position along the rete on the composition of either phospholipid fatty acids or head groups. Our results were unexpected in light of our previous demonstration of compensation of metabolic enzyme activity in the same tissue. The lack of evidence for a homeoviscous response may be due to the fluctuating nature of the thermal gradient along the visceral retia; i.e., membranes may be adapted to a eurythermal existence rather than being fine-tuned to a particular temperature.

  14. Application and validation of the TTI based chill chain management system SMAS (Safety Monitoring and Assurance System) on shelf life optimization of vacuum packed chilled tuna.

    PubMed

    Tsironi, Theofania; Gogou, Eleni; Velliou, Eirini; Taoukis, Petros S

    2008-11-30

    The objective of the study was to establish a validated kinetic model for growth of spoilage bacteria on vacuum packed tuna slices in the temperature range of 0 to 15 degrees C and to evaluate the applicability of the TTI (Time Temperature Integrators) based SMAS (Safety Monitoring and Assurance System) system to improve tuna product quality at the time of consumption in comparison to the conventional First In First Out (FIFO) approach. The overall measurements of total flora and lactic acid bacteria (LAB) on the tuna samples used in a laboratory simulated field test were in close agreement with the predictions of the developed kinetic model. The spoilage profile of the TTI bearing products, handled with SMAS, was improved. Three out of the thirty products that were handled randomly, according to the FIFO approach, were already spoiled at the time of consumption (logN(LAB)>6.5) compared to no spoiled products when handled with the SMAS approach.

  15. Risk Factors for Seabird Bycatch in a Pelagic Longline Tuna Fishery.

    PubMed

    Gilman, Eric; Chaloupka, Milani; Peschon, John; Ellgen, Sarah

    2016-01-01

    Capture in global pelagic longline fisheries threatens the viability of some seabird populations. The Hawaii longline tuna fishery annually catches hundreds of seabirds, primarily Laysan (Phoebastria immutabilis) and black-footed (P. nigripes) albatrosses. Since seabird regulations were introduced in 2001, the seabird catch rate has declined 74%. However, over the past decade, seabird catch levels significantly increased due to significant increasing trends in both effort and nominal seabird catch rates. We modelled observer data using a spatio-temporal generalized additive mixed model with zero-inflated Poisson likelihood to determine the significance of the effect of various risk factors on the seabird catch rate. The seabird catch rate significantly increased as annual mean multivariate ENSO index values increased, suggesting that decreasing ocean productivity observed in recent years in the central north Pacific may have contributed to the increasing trend in nominal seabird catch rate. A significant increasing trend in number of albatrosses attending vessels, possibly linked to declining regional ocean productivity and increasing absolute abundance of black-footed albatrosses, may also have contributed to the increasing nominal seabird catch rate. Largest opportunities for reductions are through augmented efficacy of seabird bycatch mitigation north of 23° N where mitigation methods are required and during setting instead of during hauling. Both side vs. stern setting, and blue-dyed vs. untreated bait significantly reduced the seabird catch rate. Of two options for meeting regulatory requirements, side setting had a significantly lower seabird catch rate than blue-dyed bait. There was significant spatio-temporal and seasonal variation in the risk of seabird capture with highest catch rates in April and May and to the northwest of the main Hawaiian Islands.

  16. Risk Factors for Seabird Bycatch in a Pelagic Longline Tuna Fishery

    PubMed Central

    Gilman, Eric; Chaloupka, Milani; Peschon, John; Ellgen, Sarah

    2016-01-01

    Capture in global pelagic longline fisheries threatens the viability of some seabird populations. The Hawaii longline tuna fishery annually catches hundreds of seabirds, primarily Laysan (Phoebastria immutabilis) and black-footed (P. nigripes) albatrosses. Since seabird regulations were introduced in 2001, the seabird catch rate has declined 74%. However, over the past decade, seabird catch levels significantly increased due to significant increasing trends in both effort and nominal seabird catch rates. We modelled observer data using a spatio-temporal generalized additive mixed model with zero-inflated Poisson likelihood to determine the significance of the effect of various risk factors on the seabird catch rate. The seabird catch rate significantly increased as annual mean multivariate ENSO index values increased, suggesting that decreasing ocean productivity observed in recent years in the central north Pacific may have contributed to the increasing trend in nominal seabird catch rate. A significant increasing trend in number of albatrosses attending vessels, possibly linked to declining regional ocean productivity and increasing absolute abundance of black-footed albatrosses, may also have contributed to the increasing nominal seabird catch rate. Largest opportunities for reductions are through augmented efficacy of seabird bycatch mitigation north of 23° N where mitigation methods are required and during setting instead of during hauling. Both side vs. stern setting, and blue-dyed vs. untreated bait significantly reduced the seabird catch rate. Of two options for meeting regulatory requirements, side setting had a significantly lower seabird catch rate than blue-dyed bait. There was significant spatio-temporal and seasonal variation in the risk of seabird capture with highest catch rates in April and May and to the northwest of the main Hawaiian Islands. PMID:27192492

  17. Microencapsulated krill and tuna oil blend raises plasma long-chain n-3 polyunsaturated fatty acid levels compared to tuna oil with similar increases in ileal contractility in rats.

    PubMed

    Patten, Glen S; Sanguansri, Luz; Augustin, Mary Ann; Abeywardena, Mahinda Y; Bird, Anthony R; Patch, Craig S; Belobrajdic, Damien P

    2017-03-01

    Long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) may be more bioavailable from krill oil compared to fish oil due to their phospholipid structure. We tested whether a microencapsulated krill and tuna oil blend (ME-TOKO) provided greater LC n-3 PUFA bioavailability, improved blood lipid profiles and increased intestinal contractility compared to microencapsulated tuna oil (ME-TO). Rats were divided into three groups to receive isocaloric diets containing ME-TO, ME-TOKO and microencapsulated olive oil (ME-OO) at 0.3 or 2 g/100 g for 4 weeks. Final body and organ weights, feed intake and waste output were similar. ME-TOKO rats had higher plasma total LC n-3 PUFA levels compared to ME-TO, but liver LC n-3 PUFA levels and plasma triglyceride and cholesterol levels were similar in non-fasted rats. Diets containing 2% ME-TO and ME-TOKO also showed similar increases in ileal contractility. In summary, ME-TO bioavailability of LC n-3 PUFA was similar to ME-TOKO.

  18. Two new species of parasitic nematodes from the dogtooth tuna Gymnosarda unicolor (Pisces) off the Maldive Islands.

    PubMed

    Moravec, Frantisek; Lorber, Julia; Konecný, Robert

    2007-02-01

    Two new nematode species, Philometra gymnosardae n. sp. (Philometridae) and Heptochona maldivensis n. sp. (Rhabdochonidae), are described from the dogtooth tuna Gymnosarda unicolor (Rüppell) (Scombridae, Perciformes) from the Indian Ocean off the Maldive Islands (Republic of Maldives). The former species is characterized mainly by unequal, conspicuously long (859 and 435 microm) spicules; the structure of the caudal end in the male (found in the host's stomach); by markedly large, oval cephalic papillae (n = 8) of the outer circle; the presence of a small, anterior bulb on the very long esophagus; and 2 large caudal projections in the gravid female (parasitic in the host's body cavity). This is the first-known species of Philometra whose gravid females are present in the body cavity of tuna fishes. Heptochona maldivensis resembles H. stromatei but differs mainly in the position of deirids, shape of the muscular esophagus, character of postanal papillae, length of the left spicule (648 microm), much larger body measurements, location in the host (stomach), and the host type. Rhabdochona parastromatei Bilqees, 1971, is synonymized with H. stromatei, whereas Heptochona sindica Akram and Pie de Imprenta, 1988, and H. rivdica Akram, 1988, are invalid names. Heptochona varmai is transferred to another genus as Rhabdochona varmai (Gupta and Masoodi, 1990) n. comb. Rhabdochona varmai, Heptochona schmidtii Arya, 1991, and Rhabdochona marina Lakshmi and Sudha, 1999, are considered species inquirendae.

  19. Valorisation of tuna processing waste biomass for recovery of functional and antioxidant peptides using enzymatic hydrolysis and membrane fractionation process.

    PubMed

    Saidi, Sami; Ben Amar, Raja

    2016-10-01

    The enzymatic hydrolysis using Prolyve BS coupled to membrane process (Ultrafiltration (UF) and nanofiltration (NF)) is a means of biotransformation of tuna protein waste to Tuna protein hydrolysate (TPH) with higher added values. This method could be an effective solution for the production of bioactive compounds used in various biotechnological applications and minimizing the pollution problems generated by the seafood processing industries. The amino acid composition, functional and antioxidant properties of produced TPH were evaluated. The results show that the glutamic acid, aspartic acid, glycine, alaline, valine and leucine were the major amino acids detected in the TPH profile. After membrane fractionation process, those major amino acids were concentrated in the NF retentate (NFR). The NFR and NF permeate (NFP) have a higher protein solubility (>95 %) when compared to TPH (80 %). Higher oil and water binding capacity were observed in TPH and higher emulsifying and foam stability was found in UF retentate. The NFP showed the highest DPPH radical scavenging activity (65 %). The NFR contained antioxidant amino acid (30.3 %) showed the highest superoxide radical and reducing power activities. The TPH showed the highest iron chelating activity (75 %) compared to other peptide fractions. The effect of the membrane fractionation on the molecular weight distribution of the peptide and their bioactivities was underlined. We concluded that the TPH is a valuable source of bioactive peptides and their peptide fractions may serve as useful ingredients for application in food industry and formulation of nutritional products.

  20. Fisher-Level Decision Making to Participate in Fisheries Improvement Projects (FIPs) for Yellowfin Tuna in the Philippines

    PubMed Central

    Berentsen, Paul; Bush, Simon R.; Digal, Larry; Oude Lansink, Alfons

    2016-01-01

    This study identifies the capabilities needed by small-scale fishers to participate in Fishery Improvement Projects (FIPs) for yellowfin tuna in the Philippines. The current literature provides little empirical evidence on how different models, or types of FIPs, influence the participation of fishers in their programs and the degree which FIPs are able to foster improvements in fishing practices. To address this literature gap, two different FIPs are empirically analysed, each with different approaches for fostering improvement. The first is the non-governmental organisation-led Partnership Programme Towards Sustainable Tuna, which adopts a bottom-up or development oriented FIP model. The second is the private-led Artesmar FIP, which adopts a top-down or market-oriented FIP approach. The data were obtained from 350 fishers surveyed and were analysed using two separate models run in succession, taking into consideration full, partial, and non-participation in the two FIPs. The results demonstrate that different types of capabilities are required in order to participate in different FIP models. Individual firm capabilities are more important for fishers participation in market-oriented FIPs, which use direct economic incentives to encourage improvements in fisher practices. Collective capabilities are more important for fishers to participate in development-oriented FIPs, which drive improvement by supporting fishers, fisher associations, and governments to move towards market requirements. PMID:27732607

  1. Development of a fast and selective separation method to determine histamine in tuna fish samples using capillary zone electrophoresis.

    PubMed

    Vitali, Luciano; Valese, Andressa Camargo; Azevedo, Mônia Stremel; Gonzaga, Luciano Valdemiro; Costa, Ana Carolina Oliveira; Piovezan, Marcel; Vistuba, Jacqueline Pereira; Micke, Gustavo A

    2013-03-15

    This paper reports on the development of a fast and selective separation method by capillary zone electrophoresis (CZE) for the determination of histamine in tuna fish samples. The background electrolyte was composed of 60 mmol L(-1) hydroxyisobutyric acid and 10 mmol L(-1) sodium hydroxide at pH 3.3. The internal standard used was imidazole. Separations were performed in a fused uncoated silica capillary (32 cm total length, 8.5 cm effective length and 50 μm internal diameter) with direct UV detection at 210 nm. The samples and standards were injected hydrodynamically (50 mbar, 3s) from the outlet capillary end (nearest to the detector) and the electrophoretic system was operated under normal polarity and constant voltage conditions of 30 kV (positive polarity on the injection side). The migration time of histamine in the proposed method was only 0.34 min. The method was then validated and different tuna fish samples were analyzed. Good linearity (R(2)>0.999), a limit of detection 0.14 mg L(-1), intra-day precision better than 3.5% (peak area of sample), and recovery in the range of 94-108% were obtained. The results of the histamine concentration determined in the samples by the CZE method were compared with the LC-MS/MS method.

  2. Environmental impact of bleufin tuna aquaculture on benthic assemblages in the western coast of Baja California, Mexico

    NASA Astrophysics Data System (ADS)

    Diaz-Castaneda, V.

    2013-05-01

    Sea-cage farming results in a constant rain of organic waste onto the surrounding benthos. In Baja California there is growing concern over the effects of sea-cages on the local environment: sediment chemistry and benthic communities. Samples were taken in 18 stations using a Van veen grab (0.1 m2) in Bahía Salsipuedes, Baja California in 2003, 2004, 2006 and 2008. Organisms belonging to 7 Phyla were collected: Polychaeta, Mollusca, Crustacea, Echinodermata, Cnidaria, Sipuncula and Bryozoa. Polychaetes were the dominant group followed by crustaceans and mollusks. Polychaetes were represented by 37 families and 157 species. Best represented families were Paraonidae, Cirratulidae, Spionidae, Glyceridae and Maldanidae. This study shows that in the NW area of the bay organic carbon (2.54%) and organic nitrogen (0.95%) are being accumulated (higher concentrations and lower Eh values) and smaller opportunistic species are increasing rapidly near the tuna pens. It is crucial to maintain "healthy" macrofaunal populations in order to enhance decomposition of organic matter and to prevent its excessive accumulation. The most abundant polychaete species were Aphelochaeta multifinis, Mediomastus ambiseta, Prionospio steenstrupi Spiophanes bombyx, Apoprionospio pygnaea, Paraonella sp, Monticellina sp, Aricidea (Allia) ramosa, Spiophanes bombyx and Levinsenia gracilis. The dominant trophic groups were deposit-feeders and carnivores. The buildup of organic matter on the seafloor has attracted scavenger species particularly peracarid crustaceans. Non-metric multidimensional scaling (MDS) separated stations depending of the distance to the tuna pens.

  3. A foodborne outbreak of Campylobacter jejuni (O:33) infection associated with tuna salad: a rare strain in an unusual vehicle.

    PubMed

    Roels, T H; Wickus, B; Bostrom, H H; Kazmierczak, J J; Nicholson, M A; Kurzynski, T A; Davis, J P

    1998-10-01

    We report a foodborne outbreak of Campylobacter jejuni infection in a summer camp. Outbreak-related cases occurred in 79 persons including 3 secondary cases in campers. Campylobacter jejuni was isolated from stool specimens from 16 of 21 patients who submitted a sample; 13 viable isolates were serotyped and all were serotype O:33 (somatic O scheme) or HL:18 (heat-labile scheme), and biotype III (Lior scheme). This serotype is widely distributed geographically but rarely isolated from humans. Samples of water from the wells supplying the camp were negative for faecal coliforms, and raw milk had not been served in the camp. A matched (1:1) case-control study identified tuna salad served for lunch on 19 July as the likely food item associated with illness (matched odds ratio=22; 95% confidence intervals (CI)=3.6-908). Swimming in the camp pool and other recreational water use in area lakes by the campers were not statistically associated with illness. The precise mechanism of introduction of the organism into the tuna salad remains unknown; contamination most likely occurred through cross-contamination with another food product, the hands of a food handler, or a work surface. Several deficiencies in the operation of the camp kitchen were identified. In Wisconsin, kitchens of such camps are subject to different inspection rules than restaurants. Camp staff, administrators, counselors, food managers, and infirmary staff, should fulfil important roles in their respective areas to prevent future outbreaks.

  4. Pulsed light treatment for the inactivation of selected pathogens and the shelf-life extension of beef and tuna carpaccio.

    PubMed

    Hierro, Eva; Ganan, Monica; Barroso, Elvira; Fernández, Manuela

    2012-08-01

    The efficacy of pulsed light to improve the safety of carpaccio has been investigated. Beef and tuna slices were superficially inoculated with approximately 3 log cfu/cm2 of Listeria monocytogenes, Escherichia coli, Salmonella Typhimurium and Vibrio parahaemolyticus. Fluences of 0.7, 2.1, 4.2, 8.4 and 11.9 J/cm2 were assayed. Colour, sensory and shelf-life studies were carried out. Treatments at 8.4 and 11.9 J/cm2 inactivated the selected pathogens approximately by 1 log cfu/cm2, although they modified the colour parameters and had a negative effect on the sensory quality of the product. The raw attributes were not affected by fluences of 2.1 and 4.2J/cm2 immediately after the treatment, although changes were observed during storage. The inactivation obtained with these fluences was lower than 1 log cfu/cm2, which may not be negligible in case of cross-contamination at a food plant or at a food service facility. Pulsed light showed a greater impact on the sensory quality of tuna carpaccio compared to beef. None of the fluences assayed extended the shelf-life of either product.

  5. Distribution and transportability of hexabromocyclododecane (HBCD) in the Asia-Pacific region using skipjack tuna as a bioindicator.

    PubMed

    Ueno, Daisuke; Alaee, Mehran; Marvin, Chris; Muir, Derek C G; Macinnis, Gordia; Reiner, Eric; Crozier, Patrick; Furdui, Vasile I; Subramanian, Annamalai; Fillmann, Gilberto; Lam, Paul K S; Zheng, Gene J; Muchtar, Muswerry; Razak, Hamidah; Prudente, Maricar; Chung, Kyu-hyuck; Tanabe, Shinsuke

    2006-11-01

    The geographical distribution of hexabromocyclododecane (HBCD) was investigated through analysis of muscle tissue of skipjack tuna (Katsuwonus pelamis) collected from offshore waters of Asia-Pacific region (Japan, Taiwan, Philippines, Indonesia, Seychelles, Brazil, Japan Sea, East China Sea, South China Sea, Indian Ocean and North Pacific Ocean). HBCD was detected in almost all samples analyzed (<0.1 to 45 ng/g lipid weight basis), indicating widespread presence of this compound in the marine environment. Elevated concentrations of HBCD were found in skipjack tuna from areas around Japan, which have the larger modern industrial/urban societies, and implicated these areas as primary regional sources. All three individual HBCD isomers (alpha-, gamma- and beta-HBCD) were detected in almost all samples; the percentage contribution of the alpha-isomer to total HBCD increased with increasing latitude. The estimated empirical 1/2 distance for alpha-HBCD was 8500 km, which is one of the highest atmospheric transportability among various halogenated persistent organic pollutants (POPs).

  6. Influence of the consumption of casein, or tuna in the raw, cooked or canned form, on the utilization of iron in the diet of weanling rats.

    PubMed

    García-Arias, M T; Castrillón, A M; Navarro, M P

    1994-03-01

    A study was made of the influence of the consumption of white tuna (subjected to various thermal treatments) on the bioavailability of dietary iron. Biological assays were carried out on Wistar rats fed semi-synthetic diets varying only in the protein source, casein-methionine, or tuna provided in the following forms: raw, cooked in brine, sterilized with or without soybean oil, and canned and stored for a period of 1 or 3 years. Feed intake, the fecal and urinary excretion of iron, and the iron content of the liver were monitored. Absorption of iron was enhanced by consuming the diet containing raw white tuna. However, the beneficial effect of raw tuna was greatly reduced by cooking it in brine, and even more so by sterilization, especially in the presence of oil. The benefit was partly restored by storing the conserves for a period of 1 or 3 years. It is hypothesized that structural alterations to the protein caused by thermal processes can affect the solubility and bioavailability of iron.

  7. Bioavailability of selenium from veal, chicken, beef, pork, lamb, flounder, tuna, selenomethionine, and sodium selenite assessed in selenium-deficient rats.

    PubMed

    Wen, H Y; Davis, R L; Shi, B; Chen, J J; Chen, L; Boylan, M; Spallholz, J E

    1997-01-01

    The bioavailability of selenium (Se) from veal, chicken, beef, pork, lamb, flounder, tuna, selenomethionine (SeMet), and sodium selenite was assessed in Se-deficient Fischer-344 rats. Se as veal, chicken, beef, pork, lamb, flounder, tuna, SeMet, and sodium selenite was added to torula yeast (TY) basal diets to comprise Se-inadequate (0.05 mg Se/kg) diets. Se as sodium selenite was added to a TY basal diet to comprise a Se-adequate (0.10 mg Se/kg), Se-control diet. The experimental diets were fed to weanling Fischer-344 rats that had been subjected to dietary Se depletion for 6 wk. After 9 wk of the dietary Se repletion, relative activity of liver glutathione peroxidase (GSHPx) from the different dietary groups compared with control rats (100%) was: flounder 106%, tuna 101%, pork 86%, sodium selenite 81%, SeMet 80%, beef 80%, chicken 77%, veal 77%, and lamb 58%. Se from flounder was the most efficient at restoring Se concentrations in the liver and skeletal muscle. Se from sodium selenite, SeMet, beef, veal, chicken, pork, lamb, and tuna was not dietarily sufficient to restore liver and muscle Se after 9 wk of recovery following a 6-wk period of Se depletion.

  8. Long-term monitoring of the impact of a capture-based bluefin tuna aquaculture on water column nutrient levels in the Eastern Aegean Sea, Turkey.

    PubMed

    Aksu, Mehmet; Kaymakçi-Başaran, Asli; Egemen, Ozdemir

    2010-12-01

    Capture-based aquaculture of Atlantic bluefin tuna in the Mediterranean has been expanding rapidly but little is known about its environmental impact. In order to understand the consequences of this new sector, long-term monitoring is needed. For this purpose, we investigated the impact of a capture-based tuna farm located in the Gerence Bay (Aegean Sea) on the water column on a seasonal basis from 2005 to 2008, where in the water column, temperature, salinity, pH, dissolved oxygen, nutrients (nitrite, nitrate, ammonium, and phosphate), and chlorophyll a, in the sediment organic carbon variables were measured. Although highest nutrient concentrations were observed at the cage station as compared to the two controls in the production period, differences were not statistically significant between stations. Monitoring of physico-chemical parameters, nutrients, and chlorophyll a in water column together with organic carbon in sediment did not show detectable impact of fattening of Atlantic bluefin tuna. This was probably caused by strong currents present in the area, location of the cages away from the coast, hence high water depth, controlled feeding, and periodic presence of tuna farming activity in the study area.

  9. Tuna extract reduces serum uric acid in gout-free subjects with insignificantly high serum uric acid: A randomized controlled trial

    PubMed Central

    Kubomura, Daiki; Yamada, Masanori; Masui, Ayano

    2016-01-01

    Long-term reduction of serum urate levels is vital in the treatment of gout. However, it is difficult to convince gout-free individuals of the necessity of treatment as few appropriate over-the-counter remedies and dietary supplements are available. Therefore, the present study aimed to investigate the antihyperuricemic efficacy and safety of a tuna extract containing the imidazole compounds to evaluate its potential as a functional food ingredient. A randomized, 4-week, double-blind, placebo-controlled study was conducted. A total of 48 male gout-free subjects with insignificantly high serum uric acid were randomly assigned to low- and high-dose tuna extract groups or a placebo group. The efficacy of the extract was assessed by measuring serum uric acid levels. Furthermore, a safety assessment was performed by physical parameters, hematology, blood biochemistry and urinalysis. The results indicated that the uric acid level was decreased at week 4 during the intervention in the tuna extract groups (low and high dose, −0.23 and −0.34 mg/dl, respectively) compared to the placebo group (−0.07 mg/dl). At week 4 after the intervention, a significant reduction in uric acid levels (−0.41 mg/dl; P<0.05) was observed in the high-dose tuna extract group compared with the placebo group (+0.11 mg/dl). No dose-related adverse events were observed during and following the intervention. Therefore, the present results suggest that oral administration of tuna extract containing the imidazole compounds has hypouricemic activity with no undesirable side effects. PMID:27446553

  10. Peptide derived from desalinated boiled tuna extract inhibits adipogenesis through the downregulation of C/EBP-α and PPAR-γ in 3T3-L1 adipocytes.

    PubMed

    Kim, Young-Min; Kim, Eun-Young; Kim, In-Hye; Nam, Taek-Jeong

    2015-05-01

    Recently, obesity has increased due to a variety of reasons, including the availability of 'fast food' and high-fat diets. Developing anti-obesity functional drugs and foods from natural sources may offer solutions to this global concern. Generally, tuna is a high-protein, low-fat and low-calorie food with various bioactive effects. It may improve memory, reduce cholesterol levels and positively affect the development of brain cells. In this study, we screened the anti-obesity potential of peptides derived from tuna protein. We then observed protein bands by the Coomassie blue staining of a sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel. The protein mixture was concentrated and desalted using in-gel trypsin digestion and a C18 nano column and Poros R2 reversed-phase preparation, prior to quadrupole time-of-flight mass spectrometry (Q-TOF MS/MS). We screened the peptides for their ability to affect adipogenesis in 3T3-L1 adipocytes. We also measured glucose uptake, triglyceride levels and lipid droplets using Oil Red O staining. As a result, we confirmed that one peptide inhibited adipocyte differentiation. We also observed the expression of obesity-related genes by western blot analysis and reverse transcription-polymerase chain reaction. The peptide from the tuna extract significantly reduced the expression levels of CCAAT/enhancer-binding protein α (C/EBP-α) and peroxisome proliferator-activated receptor-γ (PPAR-γ) adipocyte marker genes. Thus, our data suggest that this peptide from boiled tuna extract reduces lipid components and adipogenesis in 3T3-L1 cells, and these characteristics may be of value in the development of anti-obesity foods.

  11. Determination of trans- and cis-urocanic acid in relation to histamine, putrescine, and cadaverine contents in tuna (Auxis Thazard) at different storage temperatures.

    PubMed

    Zare, Davood; Muhammad, Kharidah; Bejo, Mohd Hair; Ghazali, H M

    2015-02-01

    Scombroid fish poisoning is usually associated with consumption of fish containing high levels of histamine. However, reports indicate that some cases have responded to antihistamine therapy while ingested histamine levels in these cases were low. Potentiation of histamine toxicity by some biogenic amines, and release of endogenous histamine by other compounds such as cis-urocanic acid (UCA) are some hypotheses that have been put forth to explain this anomaly. Very little is known about the effects of storage conditions on the production of both UCA isomers and biogenic amines in tuna. Thus, the production of trans- and cis-UCA, histamine, putrescine, and cadaverine in tuna during 15 d of storage at 0, 3, and 10 °C and 2 d storage at ambient temperature were monitored. The initial trans- and cis-UCA contents in fresh tuna were 2.90 and 1.47 mg/kg, respectively, whereas the levels of putrescine and cadaverine were less than 2 mg/kg, and histamine was not detected. The highest levels of trans- and cis-UCA were obtained during 15 d storage at 3 °C (23.74 and 21.79 mg/kg, respectively) while the highest concentrations of histamine (2796 mg/kg), putrescine (220.32 mg/kg) and cadaverine (1045.20 mg/kg) were obtained during storage at room temperature, 10 and 10 °C, respectively. Histamine content increased considerably during storage at 10 °C whereas trans- and cis-UCA contents changed slightly. The initial trans-UCA content decreased during storage at ambient temperature. Thus, unlike histamine, concentrations of trans- and cis-UCA did not result in elevated levels during storage of tuna.

  12. Enhancement of ACE and prolyl oligopeptidase inhibitory potency of protein hydrolysates from sardine and tuna by-products by simulated gastrointestinal digestion.

    PubMed

    Martínez-Alvarez, Oscar; Batista, Irineu; Ramos, Cristina; Montero, Pilar

    2016-04-01

    This work was focused on the study of the bioactive potential of three fish protein hydrolysates, one of them prepared from industrial sardine by-products (head and viscera) and the others from tuna by-products (head, and muscle and viscera). These protein hydrolysates exhibited moderate ability to inhibit Angiotensin Converting Enzyme or ACE (IC50 between 0.24-1.16 mg dry weight per ml) and prolyl oligopeptidase or PO (IC50 between 3.30-9.57 mg ml(-1)), those obtained from tuna by-products being the most effective. Overall, ACE- and PO-inhibiting activities were enhanced by sequential nanofiltration through 3 and 1 kDa MWCO membranes (IC50 between 0.02-0.16 mg ml(-1) (ACE) and 1.10-4.21 mg ml(-1) (PO)). The inhibitory properties of the hydrolysates were greatly improved by in vitro gastric digestion, and were barely affected by further intestinal digestion. The digested tuna hydrolysates, mainly that from heads, proved to be the best source of PO- and ACE- inhibiting molecules (IC50 = 0.16 mg ml(-1) (ACE) and 1.04 mg ml(-1) (PO)) and could be potential new ingredients in food with interest in the prevention or treatment of cardiovascular and neurological diseases.

  13. The Large-Scale Deployment of Fish Aggregation Devices Alters Environmentally-Based Migratory Behavior of Skipjack Tuna in the Western Pacific Ocean

    PubMed Central

    Wang, Xuefang; Chen, Yong; Truesdell, Samuel; Xu, Liuxiong; Cao, Jie; Guan, Wenjiang

    2014-01-01

    Fish aggregation devices (FADs) have been used extensively in the tuna purse seine fishery since the 1980s. This long-term modification of natural habitat has generated discussions as to whether FADs impact movement patterns of tuna species. We examined this question using data collected from the skipjack tuna (Katsuwonus pelamis) fishery. We used the longitudinal gravitational center of catch (G) to examine temporal variability in skipjack movement in the Western and Central Pacific Ocean, and related this to El Niño Southern Oscillation (ENSO) events. We found that in most cases G for free-swimming school sets changed with the onset of ENSO events, while G for floating-object-associated school sets remained relatively constant. This suggests that skipjack exhibit distinguishable behavioral strategies in response to ENSO events: they either react by moving long distances or they associate with floating objects. There has been no previous attempt to evaluate the interaction between FADs and the environmentally-determined movement of skipjack; this study shows evidence of an interaction, which should be considered when managing skipjack populations. PMID:24849561

  14. Time-Temperature-Tolerance (T. T. T.) of On-Board Frozen Tuna During Subsequent On-Land Frozen Storage with Particular Reference to Commercial Scale Trial-II

    NASA Astrophysics Data System (ADS)

    Tanaka, Takeo; Hamamoto, Yûkichi; Nishiwaki, Kôji

    As described in the preceding paper 1), there is a demand in the tuna industry from the view point of energy saving for setting up T. T. T. of on-board frozen tuna during on-land frozen storage. Three groups of tuna being composed of three different species, yellowfin (YF), southern bluefin (SB) and bigeye (BE) tuna which had been frozen on-board commercially were further stored experimentally at -40, - 30 and -20°C. K1 value (one of freshness index for fish) and K2 value (one of taste component index for fish meat) were used as quality index for T. T. T. decision. Results are as follows : Both values of three tunas examined did not change appreciably throughout storage at any temperature of -20, - 30 and -40°C. These findings indicated that T. T. T. of YF and SB was estimated to be 6 months∗ at least, and that of BE to be 17 months∗ at least as far as it was judged on bases of K1) and K2 values. (Asterisks indicate merely the length of the experimental storage, ac tual T. T. T. therefore, must be longer).

  15. Evolutionary origin of the Scombridae (tunas and mackerels): members of a paleogene adaptive radiation with 14 other pelagic fish families.

    PubMed

    Miya, Masaki; Friedman, Matt; Satoh, Takashi P; Takeshima, Hirohiko; Sado, Tetsuya; Iwasaki, Wataru; Yamanoue, Yusuke; Nakatani, Masanori; Mabuchi, Kohji; Inoue, Jun G; Poulsen, Jan Yde; Fukunaga, Tsukasa; Sato, Yukuto; Nishida, Mutsumi

    2013-01-01

    Uncertainties surrounding the evolutionary origin of the epipelagic fish family Scombridae (tunas and mackerels) are symptomatic of the difficulties in resolving suprafamilial relationships within Percomorpha, a hyperdiverse teleost radiation that contains approximately 17,000 species placed in 13 ill-defined orders and 269 families. Here we find that scombrids share a common ancestry with 14 families based on (i) bioinformatic analyses using partial mitochondrial and nuclear gene sequences from all percomorphs deposited in GenBank (10,733 sequences) and (ii) subsequent mitogenomic analysis based on 57 species from those targeted 15 families and 67 outgroup taxa. Morphological heterogeneity among these 15 families is so extraordinary that they have been placed in six different perciform suborders. However, members of the 15 families are either coastal or oceanic pelagic in their ecology with diverse modes of life, suggesting that they represent a previously undetected adaptive radiation in the pelagic realm. Time-calibrated phylogenies imply that scombrids originated from a deep-ocean ancestor and began to radiate after the end-Cretaceous when large predatory epipelagic fishes were selective victims of the Cretaceous-Paleogene mass extinction. We name this clade of open-ocean fishes containing Scombridae "Pelagia" in reference to the common habitat preference that links the 15 families.

  16. Use of a counterfactual approach to evaluate the effect of area closures on fishing location in a tropical tuna fishery

    PubMed Central

    Davies, Tim K.; Mees, Chris C.; Milner-Gulland, E. J.

    2017-01-01

    Spatial closures are widely used in marine conservation and fisheries management and it is important to understand their contribution to achieving management objectives. Many previous evaluations of closed area effects have used before-after comparisons, which, without controlling for a full range of factors, cannot ascribe changes in fleet behaviour to area closures per se. In this study we used a counterfactual approach to disentangle the effect of two closed areas on fishing location from other competing effects on the behaviour of the Indian Ocean tuna purse seine fishery. Our results revealed an inconsistent effect of the one of the closed areas between years, after taking into account the influence of environmental conditions on fleet behaviour. This suggests that the policy of closing the area per se was not the main driver for the fleet allocating its effort elsewhere. We also showed a marked difference in effect between the two closed areas resulting from their different locations in the fishery area. These findings highlight the need to account for other key fleet behavioural drivers when predicting or evaluating the contribution of area closures to achieving conservation and fishery management objectives. PMID:28355269

  17. Evolutionary Origin of the Scombridae (Tunas and Mackerels): Members of a Paleogene Adaptive Radiation with 14 Other Pelagic Fish Families

    PubMed Central

    Miya, Masaki; Friedman, Matt; Satoh, Takashi P.; Takeshima, Hirohiko; Sado, Tetsuya; Iwasaki, Wataru; Yamanoue, Yusuke; Nakatani, Masanori; Mabuchi, Kohji; Inoue, Jun G.; Poulsen, Jan Yde; Fukunaga, Tsukasa; Sato, Yukuto; Nishida, Mutsumi

    2013-01-01

    Uncertainties surrounding the evolutionary origin of the epipelagic fish family Scombridae (tunas and mackerels) are symptomatic of the difficulties in resolving suprafamilial relationships within Percomorpha, a hyperdiverse teleost radiation that contains approximately 17,000 species placed in 13 ill-defined orders and 269 families. Here we find that scombrids share a common ancestry with 14 families based on (i) bioinformatic analyses using partial mitochondrial and nuclear gene sequences from all percomorphs deposited in GenBank (10,733 sequences) and (ii) subsequent mitogenomic analysis based on 57 species from those targeted 15 families and 67 outgroup taxa. Morphological heterogeneity among these 15 families is so extraordinary that they have been placed in six different perciform suborders. However, members of the 15 families are either coastal or oceanic pelagic in their ecology with diverse modes of life, suggesting that they represent a previously undetected adaptive radiation in the pelagic realm. Time-calibrated phylogenies imply that scombrids originated from a deep-ocean ancestor and began to radiate after the end-Cretaceous when large predatory epipelagic fishes were selective victims of the Cretaceous-Paleogene mass extinction. We name this clade of open-ocean fishes containing Scombridae “Pelagia” in reference to the common habitat preference that links the 15 families. PMID:24023883

  18. Metazoan parasites in the head region of the bullet tuna Auxis rochei (Osteichthyes: Scombridae) from the western Mediterranean Sea.

    PubMed

    Mele, S; Saber, S; Gómez-Vives, M J; Garippa, G; Alemany, F; Macías, D; Merella, P

    2015-11-01

    The head region of 72 bullet tuna Auxis rochei from the western Mediterranean Sea (south-east Spain and the Strait of Gibraltar) was examined for parasites. Seven metazoan species were found in the fish from south-east Spain: three monogeneans, two trematodes and two copepods, whereas only three species were isolated in the fish from the Strait of Gibraltar. A comparison of the levels of infection of the parasites according to fish size in south-east Spain showed that the prevalence of Didymozoon auxis and the mean abundance of Allopseudaxine macrova were higher in the larger hosts (range of fork length = 38-44 cm) than in the smaller ones (33-37 cm). A comparison of the parasite infections according to geographical region showed that the mean abundances of Nematobothriinae gen. sp. and Caligus bonito were higher in fish from south-east Spain than in those from the Strait of Gibraltar. A comparison of the parasite fauna of A. rochei from the Mediterranean Sea with the published data on Auxis spp. from the Atlantic, Indian and Pacific Oceans revealed the closest similarity between the Mediterranean A. rochei and the Atlantic A. thazard.

  19. Use of a counterfactual approach to evaluate the effect of area closures on fishing location in a tropical tuna fishery.

    PubMed

    Davies, Tim K; Mees, Chris C; Milner-Gulland, E J

    2017-01-01

    Spatial closures are widely used in marine conservation and fisheries management and it is important to understand their contribution to achieving management objectives. Many previous evaluations of closed area effects have used before-after comparisons, which, without controlling for a full range of factors, cannot ascribe changes in fleet behaviour to area closures per se. In this study we used a counterfactual approach to disentangle the effect of two closed areas on fishing location from other competing effects on the behaviour of the Indian Ocean tuna purse seine fishery. Our results revealed an inconsistent effect of the one of the closed areas between years, after taking into account the influence of environmental conditions on fleet behaviour. This suggests that the policy of closing the area per se was not the main driver for the fleet allocating its effort elsewhere. We also showed a marked difference in effect between the two closed areas resulting from their different locations in the fishery area. These findings highlight the need to account for other key fleet behavioural drivers when predicting or evaluating the contribution of area closures to achieving conservation and fishery management objectives.

  20. Complex coacervation with whey protein isolate and gum arabic for the microencapsulation of omega-3 rich tuna oil.

    PubMed

    Eratte, Divya; Wang, Bo; Dowling, Kim; Barrow, Colin J; Adhikari, Benu P

    2014-11-01

    Tuna oil rich in omega-3 fatty acids was microencapsulated in whey protein isolate (WPI)-gum arabic (GA) complex coacervates, and subsequently dried using spray and freeze drying to produce solid microcapsules. The oxidative stability, oil microencapsulation efficiency, surface oil and morphology of these solid microcapsules were determined. The complex coacervation process between WPI and GA was optimised in terms of pH, and WPI-to-GA ratio, using zeta potential, turbidity, and morphology of the microcapsules. The optimum pH and WPI-to-GA ratio for complex coacervation was found to be 3.75 and 3 : 1, respectively. The spray dried solid microcapsules had better stability against oxidation, higher oil microencapsulation efficiency and lower surface oil content compared to the freeze dried microcapsules. The surface of the spray dried microcapsules did not show microscopic pores while the surface of the freeze dried microcapsules was more porous. This study suggests that solid microcapsules of omega-3 rich oils can be produced using WPI-GA complex coacervates followed by spray drying and these microcapsules can be quite stable against oxidation. These microcapsules can have many potential applications in the functional food and nutraceuticals industry.

  1. Poisoning - fish and shellfish

    MedlinePlus

    ... contaminated waters. Scombroid poisoning usually occurs from large, dark meat fish such as tuna, mackerel, mahi mahi, and albacore. Because this poison develops after a fish is caught and dies, it does not matter where the fish is caught. The main factor ...

  2. 50 CFR 300.171 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Definitions. 300.171 Section 300.171 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS Pacific Albacore Tuna Fisheries § 300.171 Definitions. In addition to the definitions in the...

  3. Influence of Amino Acid Compositions and Peptide Profiles on Antioxidant Capacities of Two Protein Hydrolysates from Skipjack Tuna (Katsuwonus pelamis) Dark Muscle

    PubMed Central

    Chi, Chang-Feng; Hu, Fa-Yuan; Wang, Bin; Li, Zhong-Rui; Luo, Hong-Yu

    2015-01-01

    Influence of amino acid compositions and peptide profiles on antioxidant capacities of two protein hydrolysates from skipjack tuna (Katsuwonus pelamis) dark muscle was investigated. Dark muscles from skipjack tuna were hydrolyzed using five separate proteases, including pepsin, trypsin, Neutrase, papain and Alcalase. Two hydrolysates, ATH and NTH, prepared using Alcalase and Neutrase, respectively, showed the strongest antioxidant capacities and were further fractionated using ultrafiltration and gel filtration chromatography. Two fractions, Fr.A3 and Fr.B2, isolated from ATH and NTH, respectively, showed strong radical scavenging activities toward 2,2-diphenyl-1-picrylhydrazyl radicals (EC50 1.08% ± 0.08% and 0.98% ± 0.07%), hydroxyl radicals (EC50 0.22% ± 0.03% and 0.48% ± 0.05%), and superoxide anion radicals (EC50 1.31% ± 0.11% and 1.56% ± 1.03%) and effectively inhibited lipid peroxidation. Eighteen peptides from Fr.A3 and 13 peptides from Fr.B2 were isolated by reversed-phase high performance liquid chromatography, and their amino acid sequences were determined. The elevated antioxidant activity of Fr.A3 might be due to its high content of hydrophobic and aromatic amino acid residues (181.1 and 469.9 residues/1000 residues, respectively), small molecular sizes (3–6 peptides), low molecular weights (524.78 kDa), and amino acid sequences (antioxidant score 6.11). This study confirmed that a smaller molecular size, the presence of hydrophobic and aromatic amino acid residues, and the amino acid sequences were the key factors that determined the antioxidant activities of the proteins, hydrolysates and peptides. The results also demonstrated that the derived hydrolysates and fractions from skipjack tuna (K. pelamis) dark muscles could prevent oxidative reactions and might be useful for food preservation and medicinal purposes. PMID:25923316

  4. Identification of factors influencing shark catch and mortality in the Marshall Islands tuna longline fishery and management implications.

    PubMed

    Bromhead, D; Clarke, S; Hoyle, S; Muller, B; Sharples, P; Harley, S

    2012-04-01

    Recent average annual catches of sharks by tuna longline vessels fishing in the Republic of the Marshall Islands (RMI) are estimated to be between 1583 and 2274 t. Although 22 shark species have been recorded by the observer programme for this fishery, 80% of the annual catch comprises only five species: blue shark Prionace glauca, silky shark Carcharhinus falciformis, bigeye thresher shark Alopias superciliosus, pelagic thresher shark Alopias pelagicus and oceanic whitetip shark Carcharhinus longimanus. Wire leaders (i.e. branch lines or traces) were also used by nearly all observed vessels. Generalized additive model (GAM)-based analyses of catch rates indicated that P. glauca and A. superciliosus are caught in higher numbers when vessels fish in relatively cooler waters, at night, close to the full moon, when the 27° C thermocline is close to the surface and during El Niño conditions. In contrast, C. falciformis, A. pelagicus and C. longimanus are caught in higher numbers when shark lines are used (all three species) or hooks are set at a shallow depth (A. pelagicus and C. longimanus and, also, P. glauca). These findings are generally consistent with current knowledge of these species' habitat preferences, movement and distribution. The results of these analyses were combined with information pertaining to shark condition and fate upon capture to compare the likely effectiveness of a range of potential measures for reducing shark mortality in the longline fishery. Of the options considered, the most effective would be to combine measures that reduce the catch rate (e.g. restrictions on the use of wire leaders, shark baits and shark lines) with measures that increase survival rates after post-capture release (e.g. finning bans).

  5. Effect of slurry ice on the functional properties of proteins related to quality loss during skipjack tuna (Katsuwonus pelamis) chilled storage.

    PubMed

    Zhang, Bin; Deng, Shang-gui; Gao, Meng; Chen, Jing

    2015-04-01

    The effect of slurry ice on the quality of Skipjack tuna (Katsuwonus pelamis) during chilling storage was investigated and compared to flake ice. Slurry ice-treated samples showed significantly higher springiness and chewiness variables than the blank and flake ice-treated samples (P < 0.05). The growth of microorganisms in tuna muscle treated with slurry ice was also down significantly (P < 0.05), and the total aerobic counts didn't reach higher scores than 5.0 log CFU/g during the whole chilling storage. Additionally, the myofibrillar protein, Ca(2+)-ATPase activity, and total sulfydryl (SH) content in muscle treated with slurry ice were all significantly higher than the blank and flake-iced samples (P < 0.05). This was probably due to the faster cooling, subzero final-temperature, and larger heat exchange derived from slurry ice. Standard error of mean and sodium dodecyl sulfate-polyacrylamide gel electrophoresis results also confirmed that slurry ice treatment could effectively retard the degradation of myofibrillar proteins and showed a positive effect on the stability of tissue structures.

  6. Time-Temperature-Tolerance(T. T. T.) of On-Board Frozen Tuna During Subsequent On-Land Frozen Storage with Particular Reference to Commercial Scale Trial-I

    NASA Astrophysics Data System (ADS)

    Tanaka, Takeo; Takahashi, Kenji; Nishiwaki, Koji

    This study was undertaken to meet the demand of the tuna industry for the definite criterion of T. T. T. of on-board frozen tuna during on-land frozen storage, from the veiw point of energy saving. Yellowfin (YF), southern bluefin (SB) and bigeye (BE) tuna which had been frozen-stored on board in semi-dressed form, excluding gills and viscera, commercially were further stored experimentally at -40, -30 and -20°C on the premise that a target of commercial storage period was 6 months. Decision on tolerance limits was given by degree of discoloration of the meat (met-myoglobin ratio). Results are as follows : T. T. T. of YF and SB was estimated to be 6 months∗ and that of BE to be 17 months∗ at -40°C, and that of the three tunas examined to be 6 months∗ at -30°C. T. T. T. of YF and SB was estimated to be 1.5 and 4-5 months (2-3 and 5 months in the case of meat block), respectively, and that of BE to be one month at -20°C. (Asterisks indicate merely the length of the experimental storage, actual T. T. T therefore, must be longer).

  7. One-pot enzymatic synthesis of docosahexaenoic acid-rich triacylglycerols at the sn-1(3) position using by-product from selective hydrolysis of tuna oil.

    PubMed

    Nagao, Toshihiro; Watanabe, Yomi; Maruyama, Kazuaki; Momokawa, Yuusuke; Kishimoto, Noriaki; Shimada, Yuji

    2011-01-31

    Docosahexaenoic acid (DHA)-rich oil has been industrially produced by selective hydrolysis of tuna oil with a lipase that acts weakly on DHA. The free fatty acids (FFAs) generated in this process as by-products contain a high DHA concentration (46wt%) but are treated as industrial waste. This study attempted to reuse these by-product FFAs using a one-pot process, and succeeded in producing triacylglycerols (TAGs) through the esterification of the by-product FFAs with glycerol using immobilized Rhizomucor miehei lipase. Regiospecific analysis of the resulting TAGs showed that the content of DHA at the sn-1(3) position (51.7mol%) was higher than the content of DHA at the sn-2 position (17.3mol%). The DHA distribution in TAGs synthesized in this study was similar to the DHA distribution in TAGs from seal oil.

  8. Effects of longitudinal body position and swimming speed on mechanical power of deep red muscle from skipjack tuna (Katsuwonus pelamis).

    PubMed

    Syme, Douglas A; Shadwick, Robert E

    2002-01-01

    The mechanical power output of deep, red muscle from skipjack tuna (Katsuwonus pelamis) was studied to investigate (i) whether this muscle generates maximum power during cruise swimming, (ii) how the differences in strain experienced by red muscle at different axial body locations affect its performance and (iii) how swimming speed affects muscle work and power output. Red muscle was isolated from approximately mid-way through the deep wedge that lies next to the backbone; anterior (0.44 fork lengths, ANT) and posterior (0.70 fork lengths, POST) samples were studied. Work and power were measured at 25 degrees C using the work loop technique. Stimulus phases and durations and muscle strains (+/- 5.5 % in ANT and +/- 8 % in POST locations) experienced during cruise swimming at different speeds were obtained from previous studies and used during work loop recordings. In addition, stimulus conditions that maximized work were determined. The stimulus durations and phases yielding maximum work decreased with increasing cycle frequency (analogous to tail-beat frequency), were the same at both axial locations and were almost identical to those used by the fish during swimming, indicating that the muscle produces near-maximal work under most conditions in swimming fish. While muscle in the posterior region undergoes larger strain and thus produces more mass-specific power than muscle in the anterior region, when the longitudinal distribution of red muscle mass is considered, the anterior muscles appear to contribute approximately 40% more total power. Mechanical work per length cycle was maximal at a cycle frequency of 2-3 Hz, dropping to near zero at 15 Hz and by 20-50% at 1 Hz. Mechanical power was maximal at a cycle frequency of 5 Hz, dropping to near zero at 15 Hz. These fish typically cruise with tail-beat frequencies of 2.8-5.2 Hz, frequencies at which power from cyclic contractions of deep red muscles was 75-100% maximal. At any given frequency over this range, power

  9. 76 FR 23962 - Fisheries Off West Coast States; Highly Migratory Species Fisheries; Annual Catch Limits and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-29

    ... determination criteria so that overfishing and overfished determinations can be made for all management unit... shall prevent overfishing while achieving, on a continuing basis, the optimum yield from each fishery... measures to end overfishing of the Pacific stock of bigeye tuna (Thunnus obesus) in response to...

  10. Susceptibility of dry-cured tuna to oxidative deterioration and biogenic amines generation: I. Effect of NaCl content, antioxidant type and ageing.

    PubMed

    Roseiro, L C; Santos, C; Gonçalves, H; Serrano, C; Aleixo, C; Partidário, A; Lourenço, A R; Dias, M Abreu; da Ponte, D J B

    2017-08-01

    This study aimed to assess lipid oxidation and biogenic amine (BA) development in "muxama", a dry-cured tuna muscle product, as affected by salt content, antioxidant type and ageing time. Overall, BA contents decreased with NaCl level (2785.1mgkg(-1), 1148.1mgkg(-1) and 307.7mgkg(-1)) and increased with ageing time (366.2mgkg(-1), 1711.8mgkg(-1) and 2959.2mgkg(-1) in the final product (T0), and after 1 (T1) and 3 (T3) months of ageing, respectively). Regardless of the test conditions, the most concentrated BA was always tyramine. For the ageing periods considered in the present study, malondialdehyde formation was affected by the NaCl level, with the saltiest samples exhibiting lower content. Rosemary and sage extracts represented promising technological options for preserving muxama from oxidation and to minimize the presence of a fishy flavour and odour, but this treatment may cause the colour to lose some of its redness and become less appealing.

  11. Large-Scale Examination of Spatio-Temporal Patterns of Drifting Fish Aggregating Devices (dFADs) from Tropical Tuna Fisheries of the Indian and Atlantic Oceans.

    PubMed

    Maufroy, Alexandra; Chassot, Emmanuel; Joo, Rocío; Kaplan, David Michael

    2015-01-01

    Since the 1990s, massive use of drifting Fish Aggregating Devices (dFADs) to aggregate tropical tunas has strongly modified global purse-seine fisheries. For the first time, a large data set of GPS positions from buoys deployed by French purse-seiners to monitor dFADs is analysed to provide information on spatio-temporal patterns of dFAD use in the Atlantic and Indian Oceans during 2007-2011. First, we select among four classification methods the model that best separates "at sea" from "on board" buoy positions. A random forest model had the best performance, both in terms of the rate of false "at sea" predictions and the amount of over-segmentation of "at sea" trajectories (i.e., artificial division of trajectories into multiple, shorter pieces due to misclassification). Performance is improved via post-processing removing unrealistically short "at sea" trajectories. Results derived from the selected model enable us to identify the main areas and seasons of dFAD deployment and the spatial extent of their drift. We find that dFADs drift at sea on average for 39.5 days, with time at sea being shorter and distance travelled longer in the Indian than in the Atlantic Ocean. 9.9% of all trajectories end with a beaching event, suggesting that 1,500-2,000 may be lost onshore each year, potentially impacting sensitive habitat areas, such as the coral reefs of the Maldives, the Chagos Archipelago, and the Seychelles.

  12. Trophic Ecology of Atlantic Bluefin Tuna (Thunnusthynnus) Larvae from the Gulf of Mexico and NW Mediterranean Spawning Grounds: A Comparative Stable Isotope Study

    PubMed Central

    Malca, Estrella; Quintanilla, José María; Muhling, Barbara A.; Alemany, Francisco; Privoznik, Sarah L.; Shiroza, Akihiro; Lamkin, John T.; García, Alberto

    2015-01-01

    The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C) as trophic indicators for Atlantic bluefin tuna larvae (BFT) (6–10 mm standard length) in the highly contrasting environmental conditions of the Gulf of Mexico (GOM) and the Balearic Sea (MED). These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton—zooplankton—larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae. PMID:26225849

  13. An overview of APECOSM, a spatialized mass balanced “Apex Predators ECOSystem Model” to study physiologically structured tuna population dynamics in their ecosystem

    NASA Astrophysics Data System (ADS)

    Maury, Olivier

    2010-01-01

    This paper gives an overview of the ecosystem model APECOSM (Apex Predators ECOSystem Model) which is developed in the framework of the GLOBEC-CLIOTOP Programme. APECOSM represents the flow of energy through the ecosystem with a size-resolved structure in both space and time. The uptake and use of energy for growth, maintenance and reproduction by the organisms are modelled according to the DEB (dynamic energy budget) theory ( Kooijmann, 2000) and the size-structured nature of predation is explicit. The pelagic community is divided into epipelagic and mesopelagic groups, the latter being subdivided into vertically migrant and non-migrant species. The model is mass-conservative. Energy is provided as the basis of the model through primary production and transferred through 3D spatially explicit size-spectra. Focus species (tunas at present, but any predator species can be considered) are “extracted” from the global size-spectra without losing mass balance and represented with more physiological and behavioural details. The forcing effects of temperature, currents, light, oxygen, primary production and fishing are explicitly taken into account.

  14. Use of Electronic Tag Data and Associated Analytical Tools to Identify and Predict Habitat Utilization of Marine Predators

    DTIC Science & Technology

    2012-01-01

    Convergence Zone (blue and mako sharks, leatherback turtles), or the eastern Pacific and Hawaiian Islands (white sharks, albacore tuna, and black...the nearshore CCLME, but also migrated into warmer, offshore waters of the Subtropical Gyre12 and the Hawaiian Islands (Figure 5c). Shortfin makos...Costa, and F. Trillmich. 2012a. Age, body mass and environmental variation shape the foraging ontogeny of Galapagos sea lions. Marine Ecology

  15. Use of Electronic Tag Data and Associated Analytical Tools to Identify and Predict Habitat Utilization of Marine Predators

    DTIC Science & Technology

    2013-09-30

    leatherback turtles), or the eastern Pacific and Hawaiian Islands (white sharks, albacore tuna, and black-footed albatrosses). The mechanisms and cues...and the Hawaiian Islands . Shortfin makos were distributed throughout the CCLME and into the Subtropical Gyre, but occupied a thermal range...P. W. Robinson, D. P. Costa, and F. Trillmich. 2012. Age, body mass and environmental variation shape the foraging ontogeny of Galapagos sea lions

  16. Large-Scale Examination of Spatio-Temporal Patterns of Drifting Fish Aggregating Devices (dFADs) from Tropical Tuna Fisheries of the Indian and Atlantic Oceans

    PubMed Central

    Maufroy, Alexandra; Chassot, Emmanuel; Joo, Rocío; Kaplan, David Michael

    2015-01-01

    Since the 1990s, massive use of drifting Fish Aggregating Devices (dFADs) to aggregate tropical tunas has strongly modified global purse-seine fisheries. For the first time, a large data set of GPS positions from buoys deployed by French purse-seiners to monitor dFADs is analysed to provide information on spatio-temporal patterns of dFAD use in the Atlantic and Indian Oceans during 2007-2011. First, we select among four classification methods the model that best separates “at sea” from “on board” buoy positions. A random forest model had the best performance, both in terms of the rate of false “at sea” predictions and the amount of over-segmentation of “at sea” trajectories (i.e., artificial division of trajectories into multiple, shorter pieces due to misclassification). Performance is improved via post-processing removing unrealistically short “at sea” trajectories. Results derived from the selected model enable us to identify the main areas and seasons of dFAD deployment and the spatial extent of their drift. We find that dFADs drift at sea on average for 39.5 days, with time at sea being shorter and distance travelled longer in the Indian than in the Atlantic Ocean. 9.9% of all trajectories end with a beaching event, suggesting that 1,500-2,000 may be lost onshore each year, potentially impacting sensitive habitat areas, such as the coral reefs of the Maldives, the Chagos Archipelago, and the Seychelles. PMID:26010151

  17. Cytotoxicity evaluation and antioxidant enzyme expression related to heavy metals found in tuna by-products meal: An in vitro study in human and rat liver cell lines.

    PubMed

    Saïdi, Saber Abdelkader; Azaza, Mohamed Salah; Windmolders, Petra; van Pelt, Jos; El-Feki, Abdelfattah

    2013-11-01

    Heavy metals can accumulate in organisms via various pathways, including respiration, adsorption and ingestion. They are known to generate free radicals and induce oxidative and/or nitrosative stress with depletion of anti-oxidants. Tuna by-product meal (TBM) is rich in proteins and can, therefore, offer an attractive protein source for animals. This study was undertaken to assess the effects of metals present in TBM, namely cadmium (Cd), lead (Pb), and mercury (Hg), separately or in combination with oxidative stress, on cell viability. Three cell models: rat liver FTO2B, human hepatoma HepG2, and human hepatic WRL-68, were used. Cell viability was determined following exposure to various concentrations of the metals. Two antioxidant genes, catalase (CAT) and superoxide dismutase (SOD), were measured to obtain a better understanding of oxidative stress-associated gene expression. Among the metals present in TBM, only Cd at a concentration of 30μM was noted to exhibit cytotoxic effects. This cytotoxicity was even more pronounced after co-stimulation with H2O2, used to mimic systemic oxidative stress. At non-toxic concentrations, Hg and Pb were noted to aggravate oxidative stress toxicity. The results further revealed that exposure to Cd, Pb, and a co-stimulation of H2O2 with Hg resulted in the increased expression of antioxidant gene SOD. A risk assessment of toxic contaminants in TBM indicated that food safety objectives should consider the human health impacts of foods derived from animals fed on contaminated meal and that much care should be taken when TBM is used in animal diet.

  18. Redescription of Rhadinorhynchus ornatus (Acanthocephala: Rhadinorhynchidae) from skipjack tuna, Katsuwonus pelamis, collected in the Pacific Ocean off South America, with special reference to new morphological features.

    PubMed

    Amin, Omar M; Heckmann, Richard A; Radwan, Nahla A E; Anchundia, Johan S Mantuano; Alcivar, Marcos A Zambrano

    2009-06-01

    Adults of Rhadinorhynchus ornatus Van Cleave, 1918 were collected from the small intestine of skipjack tuna, Katsuwonus pelamis (Linnaeus), in the high seas of the Pacific Ocean off the west coast of South America (new parasite locality record) and described using optical microscopy and a scanning electron microscope (SEM). Our specimens were somewhat comparable to those described from North America and Japan, but had more trunk spines. Definitive differences between the length and thickness of each of the dorsal and ventral proboscis hooks are noted for the first time, with most ventral middle hooks being relatively shorter and more robust than dorsal middle hooks. The SEM documented, for the first time, the different surface topography of the tegument in the proboscis, the neck, and in 3 trunk regions; the presence of microtrichs in the mid- and posterior trunk regions; the elevated base of trunk spines; the circular arrangement of basal proboscis hooks; the different morphology of all dorsal and ventral proboscis hooks and the striations of their surface; the ribbed surface topography of eggs; the elevated slit-like female gonopore; and the rimmed edge of the bursa. The presence of microtrichs on the tegumental surface is further supported by transmission electron microscopy studies. This is the first report of microtrichs in any species of Acanthocephala and the second report of striations in proboscis hooks. The geographical distribution of R. ornatus appears to correspond, at least in part, to that of its epipelagic primary host, K. pelamis, throughout the world in waters ranging in temperature from 14.7 to 30 C.

  19. Allowing macroalgae growth forms to emerge: Use of an agent-based model to understand the growth and spread of macroalgae in Florida coral reefs, with emphasis on Halimeda tuna

    USGS Publications Warehouse

    Yniguez, A.T.; McManus, J.W.; DeAngelis, D.L.

    2008-01-01

    The growth patterns of macroalgae in three-dimensional space can provide important information regarding the environments in which they live, and insights into changes that may occur when those environments change due to anthropogenic and/or natural causes. To decipher these patterns and their attendant mechanisms and influencing factors, a spatially explicit model has been developed. The model SPREAD (SPatially-explicit Reef Algae Dynamics), which incorporates the key morphogenetic characteristics of clonality and morphological plasticity, is used to investigate the influences of light, temperature, nutrients and disturbance on the growth and spatial occupancy of dominant macroalgae in the Florida Reef Tract. The model species, Halimeda and Dictyota spp., are modular organisms, with an 'individual' being made up of repeating structures. These species can also propagate asexually through clonal fragmentation. These traits lead to potentially indefinite growth and plastic morphology that can respond to environmental conditions in various ways. The growth of an individual is modeled as the iteration of discrete macroalgal modules whose dynamics are affected by the light, temperature, and nutrient regimes. Fragmentation is included as a source of asexual reproduction and/or mortality. Model outputs are the same metrics that are obtained in the field, thus allowing for easy comparison. The performance of SPREAD was tested through sensitivity analysis and comparison with independent field data from four study sites in the Florida Reef Tract. Halimeda tuna was selected for initial model comparisons because the relatively untangled growth form permits detailed characterization in the field. Differences in the growth patterns of H. tuna were observed among these reefs. SPREAD was able to closely reproduce these variations, and indicate the potential importance of light and nutrient variations in producing these patterns. ?? 2008 Elsevier B.V.

  20. Temperature effects on Ca2+ cycling in scombrid cardiomyocytes: a phylogenetic comparison

    PubMed Central

    Galli, Gina L. J.; Lipnick, Michael S.; Shiels, Holly A.; Block, Barbara A.

    2011-01-01

    Specialisations in excitation–contraction coupling may have played an important role in the evolution of endothermy and high cardiac performance in scombrid fishes. We examined aspects of Ca2+ handling in cardiomyocytes from Pacific bonito (Sarda chiliensis), Pacific mackerel (Scomber japonicus), yellowfin tuna (Thunnus albacares) and Pacific bluefin tuna (Thunnus orientalis). The whole-cell voltage-clamp technique was used to measure the temperature sensitivity of the L-type Ca2+ channel current (ICa), density, and steady-state and maximal sarcoplasmic reticulum (SR) Ca2+ content (ssSRload and maxSRload). Current–voltage relations, peak ICa density and charge density of ICa were greatest in mackerel and yellowfin at all temperatures tested. ICa density and kinetics were temperature sensitive in all species studied, and the magnitude of this response was not related to the thermal preference of the species. SRload was greater in atrial than in ventricular myocytes in the Pacific bluefin tuna, and in species that are more cold tolerant (bluefin tuna and mackerel). ICa and SRload were particularly small in bonito, suggesting the Na+/Ca2+ exchanger plays a more pivotal role in Ca2+ entry into cardiomyocytes of this species. Our comparative approach reveals that the SR of cold-tolerant scombrid fishes has a greater capacity for Ca2+ storage. This specialisation may contribute to the temperature tolerance and thermal niche expansion of the bluefin tuna and mackerel. PMID:21389190

  1. Research Required to Understand the Impact of Tactical Mid-Frequency Sonar Transmission on Fish, Fisheries and Fisheries Habitat: Summary of Stakeholder Concerns and Prioritized Research Plan from the Workshop on Mid-Frequency Sonar and Marine Fishes

    DTIC Science & Technology

    2007-09-01

    fishing quality in key fishing grounds within the USWTR (e.g., Grouper Hole and Swansboro Hole). d. Physiological Effects - Long...designated Snowy Grouper MPA. 11 Table 1. Criteria for ranking research projects. • Ease of study (rearing and handling of fish, likely...h. Snapper (Lutjanus spp.) c. Scombridae spp. i. Snowy Grouper (Epinephelus niveatus) d. Bluefin and Yellowfin Tuna (Thunnus spp.) j. Striped

  2. Direct quantification of energy intake in an apex marine predator suggests physiology is a key driver of migrations.

    PubMed

    Whitlock, Rebecca E; Hazen, Elliott L; Walli, Andreas; Farwell, Charles; Bograd, Steven J; Foley, David G; Castleton, Michael; Block, Barbara A

    2015-09-01

    Pacific bluefin tuna (Thunnus orientalis) are highly migratory apex marine predators that inhabit a broad thermal niche. The energy needed for migration must be garnered by foraging, but measuring energy intake in the marine environment is challenging. We quantified the energy intake of Pacific bluefin tuna in the California Current using a laboratory-validated model, the first such measurement in a wild marine predator. Mean daily energy intake was highest off the coast of Baja California, Mexico in summer (mean ± SD, 1034 ± 669 kcal), followed by autumn when Pacific bluefin achieve their northernmost range in waters off northern California (944 ± 579 kcal). Movements were not always consistent with maximizing energy intake: the Pacific bluefin move out of energy rich waters both in late summer and winter, coincident with rising and falling water temperatures, respectively. We hypothesize that temperature-related physiological constraints drive migration and that Pacific bluefin tuna optimize energy intake within a range of optimal aerobic performance.

  3. A comparison of myocardial beta-adrenoreceptor density and ligand binding affinity among selected teleost fishes.

    PubMed

    Olsson, H I; Yee, N; Shiels, H A; Brauner, C; Farrell, A P

    2000-11-01

    This study quantified the cell surface beta-adrenoreceptor density and ligand binding affinity in the ventricular tissue of seven teleost species; skipjack tuna (Katsowonus pelamis), yellowfin tuna (Thunnus albacares), Pacific mackerel (Scomber japonicus), mahimahi (dolphin fish; Coryphaena hippurus), sockeye salmon (Oncorhynchus nerka), rainbow trout (Oncorhynchus mykiss) and an Antarctic nototheniid (Trematomus bernacchii). Beta-Adrenoreceptor density varied by almost fourfold among these species, being highest for the athletic fish: sockeye salmon among the salmonids and skipjack tuna among the scombrids. Beta-Adrenoreceptor density was lowest for the Antarctic icefish. Beta-Adrenoreceptor binding affinity varied by almost threefold. We conclude that there is a significant species-specific variability in myocardial beta-adrenoreceptor density and binding affinity and these interspecific differences cannot be attributed to temperature even though intraspecifically cold temperature can stimulate an increase in myocardial beta-adrenoreceptor density. Instead, we suggest that interspecifically myocardial beta-adrenoreceptor density is highest in fish that inhabit tropical water.

  4. Muscle fatigue resistance in the rat hindlimb in vivo from low dietary intakes of tuna fish oil that selectively increase phospholipid n-3 docosahexaenoic acid according to muscle fibre type.

    PubMed

    Henry, R; Peoples, G E; McLennan, P L

    2015-09-28

    Dietary fish oil (FO) modulates muscle O2 consumption and contractile function, predictive of effects on muscle fatigue. High doses unattainable through human diet and muscle stimulation parameters used engender uncertainty in their physiological relevance. We tested the hypothesis that nutritionally relevant FO doses can modulate membrane fatty acid composition and muscle fatigue. Male Sprague-Dawley rats were randomised to control (10% olive oil (OO) by weight) or low or moderate FO diet (LowFO and ModFO) (HiDHA tuna fish oil) for 15 weeks (LowFO: 0.3% FO, 9.7% OO, 0.25% energy as EPA+DHA; ModFO: 1.25% FO, 8.75% OO, 1.0% energy as EPA+DHA). Hindlimb muscle function was assessed under anaesthesia in vivo using repetitive 5 s burst sciatic nerve stimulation (0.05 ms, 7-12 V, 5 Hz, 10 s duty cycle, 300 s). There were no dietary differences in maximum developed muscle force. Repetitive peak developed force fell to 50% within 62 (SEM 10) s in controls and took longer to decline in FO-fed rats (LowFO 110 (SEM 15) s; ModFO 117 (sem 14) s) (P<0.05). Force within bursts was better sustained with FO and maximum rates of force development and relaxation declined more slowly. The FO-fed rats incorporated higher muscle phospholipid DHA-relative percentages than controls (P<0.001). Incorporation of DHA was greater in the fast-twitch gastrocnemius (Control 9.3 (SEM 0.8) %, LowFO 19.9 (SEM 0.4), ModFO 24.3 (SEM 1.0)) than in the slow-twitch soleus muscle (Control 5.1 (SEM 0.2), LowFO 14.3 (SEM 0.7), ModFO 18.0 (SEM 1.4)) (P<0.001), which was comparable with the myocardium, in line with muscle fibre characteristics. The LowFO and ModFO diets, emulating human dietary and therapeutic supplement intake, respectively, both elicited muscle membrane DHA enrichment and fatigue resistance, providing a foundation for translating these physiological effects to humans.

  5. The anti-obesity effects of a tuna peptide on 3T3-L1 adipocytes are mediated by the inhibition of the expression of lipogenic and adipogenic genes and by the activation of the Wnt/β-catenin signaling pathway.

    PubMed

    Kim, Young-Min; Kim, In-Hye; Choi, Jeong-Wook; Lee, Min-Kyeong; Nam, Taek-Jeong

    2015-08-01

    The differentiation of 3T3-L1 cells into adipocytes involves the activation of an organized system of obesity-related genes, of which those encoding CCAAT/enhancer-binding proteins (C/EBPs) and the Wnt-10b protein may play integral roles. In a previous study of ours, we found that a specific peptide found in tuna (sequence D-I-V-D-K-I-E-I; termed TP-D) inhibited 3T3-L1 cell differentiation. In the present study, we observed that the expression of expression of C/EBPs and Wnt-10b was associated with obesity. The initial step of 3T3-L1 cell differentiation involved the upregulation of C/EBP-α expression, which in turn activated various subfactors. An upstream effector of glycogen synthase kinase-3β (GSK-3β) inhibited Wnt-10b expression in 3T3-L1 adipocytes. In a previous study of ours, we sequenced the tuna peptide via sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and quadrupole time-of-flight mass spectrometry (Q-TOF MS/MS) and confirmed the anti-obesity effects thereof in 3T3-L1 adipocytes. In the present study, we demonstrate that TP-D inhibits C/EBP and promotes Wnt-10b mRNA expression, thus activating the Wnt pathway. The inhibition of lipid accumulation was measured using a glucose and triglyceride (TG) assay. Our results confirmed that TP-D altered the expression levels of C/EBP-related genes in a dose-dependent manner and activated the Wnt signaling pathway. In addition, we confirmed that total adiponectin and high-molecular weight (HMW) adiponectin levels were reduced by treatment with TP-D. These data indicate that TP-D inhibits adipocyte differentiation through the inhibition of C/EBP genes and the subsequent activation of the Wnt/β-catenin signaling pathway.

  6. Species Profiles. Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (North Atlantic). American Shad.

    DTIC Science & Technology

    1986-07-01

    overfishing . The 2865,49 2,092 Atlantic coast catches are greatest in 1929 13,95209 Chesapeake Bay (Table 7). 1930 10,373 Present Fishery 1931 11,336...rostrata), and birds. At sea, adult water teeperatures of 12 to 18 °C, or shad fall prey to seals, sharks, 54 to 64 OF (Leggett and Whitney bluefin ... tuna (Thunnus thynnus), 1972). Leim (1924) claimed that kingfish (Scomberomorus regalS), and American shad eggs hatch in 12 to 15 porpoises (Scott and

  7. Survey of total mercury in some edible fish and shellfish species collected in Canada in 2002.

    PubMed

    Dabeka, R; McKenzie, A D; Forsyth, D S; Conacher, H B S

    2004-05-01

    Total mercury was measured in the edible portions of 244 selected fish and shellfish purchased in Canada at the retail level. By species, average mercury concentrations ranged from 0.011 microg g(-1) for oysters to 1.82 microg g(-1) for swordfish. The predatory fish contained the highest concentrations of mercury: swordfish (mean 1.82 microg g(-1), range 0.40-3.85 microg g(-1)), marlin (1.43, 0.34-3.19 microg g(-1)), shark (1.26, 0.087-2.73 microg g(-1)), and canned, fresh and frozen tuna (0.35, 0.020-2.12 microg g(-1)). Levels of mercury in the fresh and frozen tuna contained a mean of 0.93 microg g(-1) (range 0.077-2.12 microg g(-1)) and were substantially higher than in the canned tuna (0.15, 0.02-0.59 microg g(-1)). In the canned tuna, mercury concentrations varied with subspecies, with the highest average concentrations being found in Albacore tuna (mean 0.26 microg g(-1), range 0.19-0.38 microg g(-1)) and the lowest (0.047, 0.025-0.069 microg g(-1)) in five samples for which the subspecies of tuna were not identified. Mean concentrations of mercury in swordfish and fresh and frozen tuna were up to three times higher than reported for the USA. Dietary intake estimations found that provided fresh and frozen tuna, marlin, swordfish or shark are consumed once a month or less, the dietary intakes of total mercury by women of child-bearing age, averaged over 1 month, would fall below the Joint FAO/WHO Expert Committee on Food Additives provisional tolerable weekly intake for total mercury. The current Canadian advisory to children and women of child-bearing age is to limit their consumption of fresh and frozen tuna, swordfish and shark to no more than one meal per month.

  8. Conservation Status of Killer Whales, Orcinus orca, in the Strait of Gibraltar.

    PubMed

    Esteban, R; Verborgh, P; Gauffier, P; Alarcón, D; Salazar-Sierra, J M; Giménez, J; Foote, A D; de Stephanis, R

    Killer whales (Orcinus orca) in the Mediterranean Sea are currently restricted to the Strait of Gibraltar and surrounding waters. Thirty-nine individuals were present in 2011, with a well-differentiated social structure, organized into five pods. Killer whale occurrence in the Strait is apparently related to the migration of their main prey, Atlantic bluefin tuna (Thunnus thynnus). In spring, whale distribution was restricted to shallow waters off the western coast of the Strait where all pods were observed actively hunting tuna. In summer, the whales were observed in the shallow central waters of the Strait. A relatively new feeding strategy has been observed among two of the five pods. These two pods interact with an artisanal drop-line fishery. Pods depredating the fishery had access to larger tuna in comparison with pods that were actively hunting. The Strait of Gibraltar killer whales are socially and ecologically different from individuals in the Canary Islands. Molecular genetic research has indicated that there is little or no female-mediated gene migration between these areas. Conservation threats include small population size, prey depletion, vessel traffic, and contaminants. We propose the declaration of the Strait of Gibraltar killer whales as an endangered subpopulation. A conservation plan to protect the Strait of Gibraltar killer whales is urgently needed, and we recommend implementation of a seasonal management area where activities producing underwater noise are restricted, and the promotion of bluefin tuna conservation.

  9. 76 FR 13583 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Quotas and Atlantic Tuna Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ..., Gloucester, MA 01930. 2. Barnegat--Ocean County Library, 112 Burr Street, Barnegat, NJ 08005. 3. Manteo--Town... is the Atlantic Ocean area bounded by straight lines connecting the following coordinates in the... virtually the entire span of the western north Atlantic, as far east as the Azores and the...

  10. 76 FR 15276 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Quotas and Atlantic Tuna Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-21

    .... ACTION: Proposed rule. SUMMARY: On March 14, 2011, NMFS published a proposed rule to modify Atlantic... April 14, 2011, which would allow an approximately 30-day comment period. In order to provide additional... Fisheries, NOAA (AA). In the proposed rule, NMFS announced the end of the comment period as April, 14,...

  11. 76 FR 18504 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Quotas and Atlantic Tuna Fisheries...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ...: Notification of public hearing. ] SUMMARY: On March 14, 2011, NMFS published a proposed rule to modify Atlantic... the comment period for this action until April 28, 2011, allowing a 45-day comment period, rescheduled... greater opportunity for public comment on the proposed rule. DATES: A hearing will be held on April...

  12. Assessing niche width of endothermic fish from genes to ecosystem

    PubMed Central

    Madigan, Daniel J.; Carlisle, Aaron B.; Gardner, Luke D.; Jayasundara, Nishad; Micheli, Fiorenza; Schaefer, Kurt M.; Fuller, Daniel W.; Block, Barbara A.

    2015-01-01

    Endothermy in vertebrates has been postulated to confer physiological and ecological advantages. In endothermic fish, niche expansion into cooler waters is correlated with specific physiological traits and is hypothesized to lead to greater foraging success and increased fitness. Using the seasonal co-occurrence of three tuna species in the eastern Pacific Ocean as a model system, we used cardiac gene expression data (as a proxy for thermal tolerance to low temperatures), archival tag data, and diet analyses to examine the vertical niche expansion hypothesis for endothermy in situ. Yellowfin, albacore, and Pacific bluefin tuna (PBFT) in the California Current system used more surface, mesopelagic, and deep waters, respectively. Expression of cardiac genes for calcium cycling increased in PBFT and coincided with broader vertical and thermal niche utilization. However, the PBFT diet was less diverse and focused on energy-rich forage fishes but did not show the greatest energy gains. Ecosystem-based management strategies for tunas should thus consider species-specific differences in physiology and foraging specialization. PMID:26100889

  13. [Reasons of drifting floating objects aggregating rainbow runner (Elagatis bipinnulata)].

    PubMed

    Wang, Xue-Fang; Zhou, Cheng; Zhu, Guo-Ping; Tang, Hao; Xu, Liu-Xiong

    2014-01-01

    Many pelagic species tend to aggregate under drifting floating objects. This has led to the development of drifting fish aggregation devices (FADs) to attract the tropical tunas for the tuna purse seine fishery. However, FADs can also attract other non-targeting small pelagic species such as rainbow runner Elagatis bipinnulata, although it is still unclear why those species can be attracted and aggregated under an FAD. Using the fishery biological data collected in the Western and Central Pacific Ocean by the scientific observers on board Chinese tuna purse seine fishing vessels, we evaluated the potential motivations for rainbow runner to aggregate under drifting objects. This study indicated 1) Fork length of rainbow runner ranged from 30.0 to 90.6 cm, with the dominant fork lengths of 60.0 to 80.0 cm, accounting for 76.3% of the total sampled fish, suggesting large rainbow runner dominating around the drifting objects; 2) Size (fork length) of E. bipinnulata at 50% maturity was 65.7 cm, and mature individuals were dominant under the FADs; and 3) Some commonly observed small fish species, such as Decapterus macarellus, Kyphosus cinerascens, Caranx sexfasciatus, Katsuwonus pelamis and the juveniles of Thunnus obesus and Thunnus albacares, were found in the stomach of rainbow runner, which suggested that rainbow runner under FAD preyed on other associated small pelagic species. As an oceanic predator associated with drifting objects, feeding is perhaps one of the most possible motivations for adult E. bipinnulata to aggregate under the FAD. Both the "concentration of food supply" hypothesis and the "comfortability stipulation" hypothesis can be used to explain why E. bipinnulata aggregate under drifting floating objects.

  14. Pelagic cephalopods in the western Indian Ocean: New information from diets of top predators

    NASA Astrophysics Data System (ADS)

    Ménard, Frédéric; Potier, Michel; Jaquemet, Sébastien; Romanov, Evgeny; Sabatié, Richard; Cherel, Yves

    2013-10-01

    Using a combination of diverse large predatory fishes and one seabird, we collected information on the cephalopod fauna of the western Indian Ocean. We analyzed the stomach contents of 35 fishes representing ten families (Xiphiidae, Istiophoridae, Scombridae, Carangidae, Coryphaenidae, Alepisauridae, Dasyatidae, Carcharhinidae, Alopiidae and Sphyrnidae) and of the sooty tern Onychoprion fuscata of the Mozambique Channel from 2000 to 2010. Both fresh and accumulated beaks were used for identifying cephalopod prey. Cephalopods were important prey for twelve predators; swordfish Xiphias gladius had the highest cephalopod proportion; sooty tern (O. fuscata) and bigeye tuna (Thunnus obesus) had high proportions too. We recovered 23 cephalopod families and identified 38 species. Ten species from four Teuthida families (Ommastrephidae, Onychoteuthidae, Histioteuthidae and Ancistrocheiridae) and two Octopoda families (Argonautidae and Bolitaenidae) occurred very frequently in the stomach contents, while Sepiida were rare. Ommastrephidae were the most cephalopod food sources: the purpleback flying squid Sthenoteuthis oualaniensis was the most prevalent prey by far, Ornithoteuthis volatilis was important for eleven predators and few but large specimens of the neon flying squid Ommastrephes bartramii were recovered in the stomachs of swordfish in the Indian South Subtropical Gyre province only. Predators' groups were identified based on cephalopod prey composition, on depth in which they forage, and on prey size. Surface predators' diets were characterized by lower cephalopod diversity but greater average numbers of cephalopod prey, whereas the deep-dwelling predators (swordfish and bigeye tuna) preyed on larger specimens than surface predators (O. fuscata or yellowfin tunas Thunnus albacares). Our findings emphasized the usefulness of a community of marine predators to gain valuable information on the biology and the distribution of the cephalopod forage fauna that are

  15. Methyl mercury concentrations in edible fish and shellfish from Dunedin, and other regions around the South Island, New Zealand.

    PubMed

    Sadhu, Ashish K; Kim, Jonathan P; Furrell, Hamish; Bostock, Ben

    2015-12-15

    Methyl mercury (MeHg) concentrations were determined in edible fish and shellfish available in local markets in Dunedin, New Zealand. While most of the fish species were sourced in Dunedin, some specimens of fish were also collected from waters off Picton, around Stewart Island and also off-shore of the South Island in the Puysegur and Subantarctic regions. The concentrations of MeHg were analysed in 25 different fish species and shellfish (103 muscle tissue samples). Total mercury (HgT) levels were also analysed in a few (n=12) selected fish samples. Most of the Hg was in the form of MeHg (≥ 96%). Higher MeHg concentrations were found in fish at higher trophic levels, particularly in predatory fish species such as ling, school shark, spiny dogfish and albacore tuna. Concentrations of MeHg in all samples ranged from 0.002 to 2.515 μg MeHg/g.

  16. Oceanic δ15N biogeography: a novel top-down approach to examine nutrient dynamics in the equatorial Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Graham, B. S.; Fry, B.; Popp, B. N.; Allain, V.; Olson, R.; Galvan, F.

    2010-12-01

    By mapping the δ15N and δ13C values of three top-level pelagic predators, yellowfin (Thunnus albacares), bigeye (T. obesus), and skipjack (Katsuwonus pelamis) tuna throughout the equatorial Pacific Ocean, we demonstrated systematic geographic isotopic variation (up to ~12‰ for the δ15N values) that reflect nutrient dynamics that occur at the base of the food web. Remarkably the variation observed in the δ15N values of the tunas is geographically similar to δ15N values previously reported in surface particulate organic matter and deep-sea sediments in the tropical Pacific. We discuss the mechanisms occurring at the base of the food web that could produce the spatial variability observed in tropical tuna δ15N values. We present a simple Rayleigh fractionation model that can explain much of the spatial structure. We also discuss the temporal stability in the isotopic compositions at the base and top of the food web. Overall, this nitrogen isotope cartography or “isoscapes” suggests nitrogen is tightly retained in the marine food web, up to the top predators, and that the uptake of nitrate from the equatorial upwelling zone, denitrification in the oxygen minimum zones, and nitrogen fixation at the base of the food web play major roles in the observed geographical variation. In addition to providing insight into the nutrient dynamics of the open ocean, these predator isoscapes can begin to be used to characterize regional residency in tropical tunas, which is important for the successful management of tuna fisheries.

  17. A new compilation of stomach content data for commercially important pelagic fish species in the northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Pinnegar, J. K.; Goñi, N.; Trenkel, V. M.; Arrizabalaga, H.; Melle, W.; Keating, J.; Óskarsson, G.

    2015-02-01

    There is increasing demand for information on predator-prey interactions in the ocean as a result of legislative commitments aimed at achieving sustainable exploitation. However, comprehensive data sets are lacking for many fish species and this has hampered development of multispecies fisheries models and the formulation of effective food-web indicators. This work describes a new compilation of stomach content data for five pelagic fish species (herring, blue whiting, mackerel, albacore and bluefin tuna) sampled across the northeast Atlantic and submitted to the PANGAEA open-access data portal (www.pangaea.de). We provide detailed descriptions of sample origin and of the corresponding database structures. We describe the main results in terms of diet composition and predator-prey relationships. The feeding preferences of small pelagic fish (herring, blue whiting, mackerel) were sampled over a very broad geographic area within the North Atlantic basin, from Greenland in the west, to the Lofoten Islands in the east and from the Bay of Biscay northwards to the Arctic. This analysis revealed significant differences in the prey items selected in different parts of the region at different times of year. Tunas (albacore and bluefin) were sampled in the Bay of Biscay and Celtic Sea. Dominant prey items for these species varied by location, year and season. This data compilation exercise represents one of the largest and most wide-ranging ever attempted for pelagic fish in the North Atlantic. The earliest data included in the database were collected in 1864, whereas the most recent were collected in 2012. Data sets are available at doi:10.1594/PANGAEA.820041 and doi:10.1594/PANGAEA.826992.

  18. A new compilation of stomach content data for commercially-important pelagic fish species in the Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Pinnegar, J. K.; Goñi, N.; Trenkel, V. M.; Arrizabalaga, H.; Melle, W.; Keating, J.; Óskarsson, G.

    2014-04-01

    There is increasing demand for information on predator-prey interactions in the ocean as a result of legislative commitments aimed at achieving sustainable exploitation. However, comprehensive datasets are lacking for many fish species and this has hampered development of multispecies fisheries models and the formulation of effective food-web indicators. This work describes a new compilation of stomach content data for five pelagic fish species (herring, blue whiting, mackerel, albacore and bluefin tuna) sampled across the northeast Atlantic and submitted to the PANGAEA open-access data portal (www.pangaea.de). We provide detailed descriptions of sample origin and of the corresponding database structures. We describe the main results in terms of diet composition and predator-prey relationships. The feeding preferences of small pelagic fish (herring, blue whiting, mackerel) were sampled over a very broad geographic area within the North Atlantic basin, from Greenland in the west, to the Lofoten Islands in the east and from the Bay of Biscay northwards to the Arctic. This analysis revealed significant differences in the prey items selected in different parts of the region at different times of year. Tunas (albacore and bluefin) were sampled in the Bay of Biscay and Celtic Sea. Dominant prey items for these species varied by location, year and season. This data compilation exercise represents one of the largest and most wide-ranging ever attempted for pelagic fish in the north Atlantic. The earliest data included in the database were collected in 1864, whereas the most recent were collected in 2012.Datasets are available at doi:10.1594/PANGAEA.820041 and doi:10.1594/PANGAEA.826992.

  19. Structural adaptations for ram ventilation: gill fusions in scombrids and billfishes.

    PubMed

    Wegner, Nicholas C; Sepulveda, Chugey A; Aalbers, Scott A; Graham, Jeffrey B

    2013-01-01

    For ram-gill ventilators such as tunas and mackerels (family Scombridae) and billfishes (families Istiophoridae, Xiphiidae), fusions binding the gill lamellae and filaments prevent gill deformation by a fast and continuous ventilatory stream. This study examines the gills from 28 scombrid and seven billfish species in order to determine how factors such as body size, swimming speed, and the degree of dependence upon ram ventilation influence the site of occurrence and type of fusions. In the family Scombridae there is a progressive increase in the reliance on ram ventilation that correlates with the elaboration of gill fusions. This ranges from mackerels (tribe Scombrini), which only utilize ram ventilation at fast cruising speeds and lack gill fusions, to tunas (tribe Thunnini) of the genus Thunnus, which are obligate ram ventilators and have two distinct fusion types (one binding the gill lamellae and a second connecting the gill filaments). The billfishes appear to have independently evolved gill fusions that rival those of tunas in terms of structural complexity. Examination of a wide range of body sizes for some scombrids and billfishes shows that gill fusions begin to develop at lengths as small as 2.0 cm fork length. In addition to securing the spatial configuration of the gill sieve, gill fusions also appear to increase branchial resistance to slow the high-speed current produced by ram ventilation to distribute flow evenly and optimally to the respiratory exchange surfaces.

  20. Identifying pelagic fish eggs in the southeast Yucatan Peninsula using DNA barcodes.

    PubMed

    Leyva-Cruz, E; Vásquez-Yeomans, L; Carrillo, L; Valdez-Moreno, M

    2016-12-01

    In the waters surrounding Banco Chinchorro in the Mexican Caribbean are spawning and nursery areas for many types of fish. In this natural environment, as opposed to under controlled laboratory conditions, it is almost impossible to link an individual egg to the adult that laid it. This makes identifying the species of the eggs difficult. However, DNA barcodes have made this easier. In the present study, 300 eggs were processed for molecular analysis, from which 139 sequences were obtained. We identified 42 taxa (33 species with their binomial names), 35 genera, and 24 families. The identified eggs included those from Ariomma melanum, which is the first recording of this species in the Mexican Caribbean. Eggs from economically important fish species were also identified, including frigate tuna (Auxis thazard), crevalle jack (Caranx hippos), common dolphinfish (Coryphaena hippurus), sailfish (Istiophorus platypterus), white marlin (Kajikia albida), skipjack tuna (Katsuwonus pelamis), blackfin tuna (Thunnus atlanticus), and swordfish (Xiphias gladius). We have also described new morphological characteristics and captured photographs for 21 species, as well as obtained new information about spawning locality and time for 16 species. This valuable information will provide the basis to develop more effective conservation measures for sustainable fisheries and protection of the Mesoamerican Barrier Reef System.

  1. Direct quantification of energy intake in an apex marine predator suggests physiology is a key driver of migrations

    PubMed Central

    Whitlock, Rebecca E.; Hazen, Elliott L.; Walli, Andreas; Farwell, Charles; Bograd, Steven J.; Foley, David G.; Castleton, Michael; Block, Barbara A.

    2015-01-01

    Pacific bluefin tuna (Thunnus orientalis) are highly migratory apex marine predators that inhabit a broad thermal niche. The energy needed for migration must be garnered by foraging, but measuring energy intake in the marine environment is challenging. We quantified the energy intake of Pacific bluefin tuna in the California Current using a laboratory-validated model, the first such measurement in a wild marine predator. Mean daily energy intake was highest off the coast of Baja California, Mexico in summer (mean ± SD, 1034 ± 669 kcal), followed by autumn when Pacific bluefin achieve their northernmost range in waters off northern California (944 ± 579 kcal). Movements were not always consistent with maximizing energy intake: the Pacific bluefin move out of energy rich waters both in late summer and winter, coincident with rising and falling water temperatures, respectively. We hypothesize that temperature-related physiological constraints drive migration and that Pacific bluefin tuna optimize energy intake within a range of optimal aerobic performance. PMID:26601248

  2. Migratory patterns of pelagic fishes and possible linkages between open ocean and coastal ecosystems off the Pacific coast of North America

    NASA Astrophysics Data System (ADS)

    Beamish, R. J.; McFarlane, G. A.; King, J. R.

    2005-03-01

    We review studies relevant to the migration of pelagic fishes between the coastal and open-ocean ecosystems off the subarctic coast of North America. We review the life history strategies of these migratory fish and to compare to the life history strategies of major coastal migrants. The oceanography in this region is dominated by north and south currents that provide a boundary between the offshore and coastal waters. Commercial fisheries off the west coast of North America are virtually all inshore of this oceanographic separation. Migrations for some species in these major fisheries are also north and south rather than east and west. However, exceptions occur for Pacific salmon, species associated with seamounts, and for transitional pelagic species such as tuna, squid and sharks. Three species of Pacific salmon, sockeye, pink and chum salmon, migrate along the coast in their first marine year and move off shore in the fall and winter in their first marine year. Three other species, coho salmon, chinook salmon, and steelhead trout, also migrate offshore, although they are less abundant and some stocks remain within the coastal regions. Pacific salmon species are a dominant daytime biomass in the surface waters in the offshore areas. It is known that albacore tuna and some sharks migrate between the offshore and coastal areas, but more research is needed to assess the relative importance of these migrations. Although the biomass of species on seamounts is small relative to coastal areas, the similarity in fauna is evidence that there is recruitment from coastal ecosystems.

  3. Correlation between some selected trace metal concentrations in six species of fish from the Arabian Sea

    SciTech Connect

    Ashraf, M.; Jaffar, M.

    1988-07-01

    The role of trace metals in marine ecosystems has been keenly investigated during recent years. It is known that abundance of essential trace metals regulates the metal content in the organisms by homeostatic control mechanisms, which when cease to function cause essential trace metals to act in an either acutely or chronically toxic manner. Therefore, a correlation study based on essential and non-essential trace metal concentrations is imperative for extending the existing knowledge of bioaccumulation of trace metals in marine organisms. An attempt has been made in the present investigation to bring out quantitative correlations between the concentrations of iron, copper, lead and zinc in the edible muscle tissue of six species of marine fish: Salmon (salmon sole); tuna (thunnus thynnus); pomfret silver (pampus argenteus); Pomfret black (formioniger); long tail tuna (thynnus tonggel) and Indian oil sardine (sardinella longiceps). These fish are abundantly available in Pakistan along the coastal line of the Arabian Sea and have great commercial value. The computational analysis on the trace metal correlation was conducted using an MSTAT statistical package.

  4. Molecular characterisation of Anisakidae larvae from fish in Adriatic Sea.

    PubMed

    Vardić Smrzlić, I; Valić, D; Kapetanović, D; Kurtović, B; Teskeredžić, E

    2012-12-01

    In the present study, anisakids from: tuna (Thunnus thynnus) fattened in the Croatian farm in middle Adriatic Sea, three different feral fish species caught near tuna farm (Trachurus trachurus, Scomber japonicus and Oblada melanura) and fish marketed in Croatia (T. trachurus) were analysed by morphology and molecular methods. Larvae were identified to the species level by PCR restriction fragment length polymorphism and characterised by sequencing of nuclear (internal transcribed spacer) and mitochondrial (cytochrome c oxidase subunit 2) markers. The results revealed diverse Anisakidae community consisting of: Anisakis pegreffi, Anisakis simplex (s.s.), Anisakis typica and Hysterothylacium aduncum. This is the first report of A. typica in Adriatic Sea, and also the first record of this species in T. thynnus as host in Mediterranean Sea. Molecular identification of H. aduncum found in co-infection with Anisakis larvae type I expands our knowledge of the occurrence of these taxa in the Adriatic Sea. Zoonotic Anisakidae worms found in fish from the Adriatic Sea could represent a risk to acquire parasitic infection/allergies in Croatia.

  5. Consistently low mercury concentrations in dolphinfish, Coryphaena hippurus, an oceanic pelagic predator.

    PubMed

    Adams, Douglas H

    2009-08-01

    Compared to total mercury concentrations in other oceanic pelagic and syntopic fish species examined from waters of the southeastern United States (e.g., king mackerel, Scomberomorus cavalla; wahoo, Acanthocybium solanderi; yellowfin tuna, Thunnus albacares; blackfin tuna, T. atlanticus), total mercury concentrations in dolphinfish, Coryphaena hippurus, examined were consistently low. Dorsal-muscle tissue from 385 dolphinfish (317-1395 mm fork length) from Florida offshore waters was analyzed for total mercury content. Total mercury concentration in individual fish ranged from 0.012 to 0.55 mg/kg (wet weight), with a mean of 0.10 mg/kg (+/- 0.089 SD). Compared to mercury concentrations in other similar species, mercury concentrations detected in dolphinfish did not vary widely with respect to fish size, estimated age, or sex. A positive relationship between total mercury concentrations and fish length was observed, indicating that mercury tends to increase moderately over time as dolphinfish grow. Low mercury concentrations in dolphinfish occur on a global scale throughout tropical and subtropical waters. The short life span, rapid growth rate, known physiology, and feeding ecology of dolphinfish are comparable regardless of where they are found, suggesting that the forcing factors that influence mercury concentrations in this species are similar throughout its circumtropical range.

  6. A Statistical Analysis for Estimating Fish Number Density with the Use of a Multibeam Echosounder

    NASA Astrophysics Data System (ADS)

    Schroth-Miller, Madeline L.

    Fish number density can be estimated from the normalized second moment of acoustic backscatter intensity [Denbigh et al., J. Acoust. Soc. Am. 90, 457-469 (1991)]. This method assumes that the distribution of fish scattering amplitudes is known and that the fish are randomly distributed following a Poisson volume distribution within regions of constant density. It is most useful at low fish densities, relative to the resolution of the acoustic device being used, since the estimators quickly become noisy as the number of fish per resolution cell increases. New models that include noise contributions are considered. The methods were applied to an acoustic assessment of juvenile Atlantic Bluefin Tuna, Thunnus thynnus. The data were collected using a 400 kHz multibeam echo sounder during the summer months of 2009 in Cape Cod, MA. Due to the high resolution of the multibeam system used, the large size (approx. 1.5 m) of the tuna, and the spacing of the fish in the school, we expect there to be low fish densities relative to the resolution of the multibeam system. Results of the fish number density based on the normalized second moment of acoustic intensity are compared to fish packing density estimated using aerial imagery that was collected simultaneously.

  7. 77 FR 44592 - Atlantic Highly Migratory Species; Electronic Dealer Reporting System Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-30

    ... swordfish, shark, and tunas dealers (except for dealers reporting Atlantic bluefin tuna) to report... maintain optimum yield, rebuild overfished fisheries, and prevent overfishing. Atlantic Tunas Convention... tunas dealers (except for dealers reporting Atlantic bluefin tuna) to report commercially-...

  8. Mercury content in commercial pelagic fish and its risk assessment in the Western Indian Ocean.

    PubMed

    Kojadinovic, Jessica; Potier, Michel; Le Corre, Matthieu; Cosson, Richard P; Bustamante, Paco

    2006-08-01

    As top predators of pelagic food webs, large fish naturally bioaccumulate mercury (Hg). Determining Hg burdens in commercialized fish is essential considering the concern about effects of contaminants on human health and the legal thresholds that are therefore set for local consumption and/or exportation. Total Hg levels were measured in the muscular tissue of 183 fish of five commercially important species from the tropical zone of the Western Indian Ocean. All individuals were measured and sexed in order to study the impregnation of Hg with size and sex within each species. Values of Hg found in this part of the Indian Ocean were comparable to Hg in muscular tissue of the same species studied in other areas. The highest Hg levels were noted in Swordfish (Xiphias gladius) caught in waters surrounding Reunion Island (3.97+/-2.67 microg g(-1) dry weight). Following the Swordfish, in decreasing order of Hg content, were the Yellowfin Tuna (Thunnus albacares) and the Skipjack (Katsuwonus pelamis), then the Common Dolphinfish (Coryphaena hippurus) and the Wahoo (Acanthocybium solandri). In the North of the Mozambique Channel, Swordfish had higher Hg levels than Yellowfin Tunas, and Dolphinfish exhibited intermediate Hg levels. The size of a fish was a determining factor of its Hg burden, as was the species. Differences in size-normalized Hg levels were observed between the two study zones for Swordfish and Common Dolphinfish. Sex, in contrast, did not influence Hg levels suggesting that females and males have similar feeding habits. The muscular Hg levels presented here suggest that consumers of fish originating from the Western Indian Ocean should limit themselves to one Swordfish based meal per week, or one fish meal a day if they choose to eat tuna or Common Dolphinfish.

  9. Mean trophic level of coastal fisheries landings in the Persian Gulf (Hormuzgan Province), 2002-2011

    NASA Astrophysics Data System (ADS)

    Razzaghi, Marzieh; Mashjoor, Sakineh; Kamrani, Ehsan

    2016-06-01

    Fishing activities can alter the structure of marine food webs by the selective removal of some species. The changes in the marine food webs of the Hormuzgan waters of the Persian Gulf, Iran were assessed, based on estimates of the mean trophic index (MTI) and Fishing in Balance index (FiB), and on landing profile of the exploited marine community (49 species) during the period, 2002-2011. The total landings (Y t) (R=0.88, P<0.001) increased gradually while the Y t of carnivores has slightly declined, and the Y t of herbivores, detritivores and omnivores has increased. Consequently, the MTI significantly decreased (R =-0.69, P<0.05) at a rate of 0.11 during this decade. The MTI showed a decreasing trend, which indicates exploitation of marine resources. The FiB index also showed a downward trend and negative values from 2002 to 2009, which may be associated with unbalanced structure in the fisheries, but an upward trend from 2009 to 2011. The time variation of the landing profile showed two periods with significant diff erences in their species composition (R=0.88; P =0.005), and based on analysis of similarity, species have been identified as discriminator species, namely Thunnus albacores and Benthosema pterotum. Results indicate that changes in MTI reflected changes in the Hormuzgan landing structure. The examination of the MTI, FBI, and landing profile (LP) temporal pattern suggests that the status of fishery resources in Hormuzgan inshore waters is overexploited, and provides evidence of the probability that a fishing down process is occurring in this area, and that this trend may continue in the long-term. Therefore, environmental fisheries management and conservation programs should be prioritized for these valuable resources.

  10. Interannual differences for sea turtles bycatch in Spanish longliners from Western Mediterranean Sea.

    PubMed

    Báez, José C; Macías, David; García-Barcelona, Salvador; Real, Raimundo

    2014-01-01

    Recent studies showed that regional abundance of loggerhead and leatherback turtles could oscillate interannually according to oceanographic and climatic conditions. The Western Mediterranean is an important fishing area for the Spanish drifting longline fleet, which mainly targets swordfish, bluefin tuna, and albacore. Due to the spatial overlapping in fishing activity and turtle distribution, there is an increasing sea turtle conservation concern. The main goal of this study is to analyse the interannual bycatch of loggerhead and leatherback turtles by the Spanish Mediterranean longline fishery and to test the relationship between the total turtle by-catch of this fishery and the North Atlantic Oscillation (NAO). During the 14 years covered in this study, the number of sea turtle bycatches was 3,940 loggerhead turtles and 8 leatherback turtles, 0.499 loggerhead turtles/1000 hooks and 0.001014 leatherback turtles/1000 hooks. In the case of the loggerhead turtle the positive phase of the NAO favours an increase of loggerhead turtles in the Western Mediterranean Sea. However, in the case of leatherback turtle the negative phase of the NAO favours the presence of leatherback turtle. This contraposition could be related to the different ecophysiological response of both species during their migration cycle.

  11. The Transition Zone Chlorophyll Front updated: Advances from a decade of research

    NASA Astrophysics Data System (ADS)

    Polovina, Jeffrey J.; Howell, Evan A.; Kobayashi, Donald R.; Seki, Michael P.

    2017-01-01

    The dynamic ocean feature called the Transition Zone Chlorophyll Front (TZCF) was first described fifteen years ago based on an empirical association between the apparent habitat of loggerhead sea turtles and albacore tuna linked to a basin-wide chlorophyll front observed with remotely sensed ocean color data. Subsequent research has provided considerable evidence that the TZCF is an indicator for a dynamic ocean feature with important physical and biological characteristics. New insights into the seasonal dynamics of the TZCF suggest that in the summer it is located at the southern boundary of the subarctic gyre while its position in the winter and spring is defined by the extent of the southward transport of surface nutrients. While the TZCF is defined as the dynamic boundary between low and high surface chlorophyll, it appears to be a boundary between subtropical and subarctic phytoplankton communities. Furthermore, the TZCF is also characterized as supporting enhanced phytoplankton net community production throughout its seasonal migration. Lastly, the TZCF is important to the growth rate of neon flying squid and to the survival of monk seal pups in the northern atolls of the Hawaiian Archipelago. This paper reviews these and other findings that advance our current understanding of the physics and biology of the TZCF from research over the past decade.

  12. Interannual Differences for Sea Turtles Bycatch in Spanish Longliners from Western Mediterranean Sea

    PubMed Central

    Báez, José C.; García-Barcelona, Salvador

    2014-01-01

    Recent studies showed that regional abundance of loggerhead and leatherback turtles could oscillate interannually according to oceanographic and climatic conditions. The Western Mediterranean is an important fishing area for the Spanish drifting longline fleet, which mainly targets swordfish, bluefin tuna, and albacore. Due to the spatial overlapping in fishing activity and turtle distribution, there is an increasing sea turtle conservation concern. The main goal of this study is to analyse the interannual bycatch of loggerhead and leatherback turtles by the Spanish Mediterranean longline fishery and to test the relationship between the total turtle by-catch of this fishery and the North Atlantic Oscillation (NAO). During the 14 years covered in this study, the number of sea turtle bycatches was 3,940 loggerhead turtles and 8 leatherback turtles, 0.499 loggerhead turtles/1000 hooks and 0.001014 leatherback turtles/1000 hooks. In the case of the loggerhead turtle the positive phase of the NAO favours an increase of loggerhead turtles in the Western Mediterranean Sea. However, in the case of leatherback turtle the negative phase of the NAO favours the presence of leatherback turtle. This contraposition could be related to the different ecophysiological response of both species during their migration cycle. PMID:24764769

  13. Ranking the contributions of commercial fish and shellfish varieties to mercury exposure in the United States: implications for risk communication.

    PubMed

    Groth, Edward

    2010-04-01

    Fish and shellfish have important nutritional benefits, and US per capita seafood consumption has increased substantially since 2002. Recent research has reinforced concerns about adverse effects of methylmercury exposure, suggesting that methylmercury doses associated with typical US rates of fish consumption may pose measurable risks, with no threshold. These converging trends create a need to improve risk communication about fish consumption and mercury. The analysis performed here identifies the relative importance of different fish and shellfish as sources of mercury in the US seafood supply and proposes improved consumer advice, so that the public can benefit from fish consumption while minimizing mercury exposure. I have quantified contributions to total mercury in the US seafood supply by 51 different varieties of fish and shellfish, then ranked and sorted the 51 varieties in terms of relative impact. Except for swordfish, most fish with the highest mercury levels are relatively minor contributors to total inputs. Tuna (canned light, canned albacore and fresh/frozen varieties) accounts for 37.4 percent of total mercury inputs, while two-thirds of the seafood supply and nine of the 11 most heavily consumed fish and shellfish are low or very low in mercury. Substantial improvement in risk communication about mercury in fish and seafood is needed; in particular, several population subsets need better guidance to base their seafood choices more explicitly on mercury content. I have sorted the 51 seafood varieties into six categories based on mercury levels, as a framework for improving risk communication in this regard.

  14. Determination of total mercury in seafood and other protein-rich products

    SciTech Connect

    Landi, S.; Fagioli, F.; Locatelli, C.

    1992-11-01

    A previously developed wet-digestion method for the determination of total mercury in plants by cold vapor atomic absorption spectroscopy (CVAAS) was extended to the analysis of seafood and other products rich in proteins. Oxidation of matrixes is accomplished by K{sub 2}Cr{sub 2}O{sub 7} in the presence of diluted H{sub 2}SO{sub 4}; a simple air condenser is used to reflux vapors released from the boiling mixture. The original procedure (A) and 2 modifications (B and C), which differ with respect to the mode of acidification and/or digestion time and the types of condensers used, were compared for precision and accuracy by means of National Institute of Standards and Technology Research Material 50 Albacore Tuna and proved to be reliable (Hg present, 0.95{plus_minus}0.1 {mu}g/g; Hg found, 0.97 {plus_minus} 0.029 {mu}g/g [A], 0.98 {plus_minus} 0.018 {mu}g/g [B], and 0.94 {plus_minus} 0.025 {mu}g/g [C]). The modified procedures were tested further in Hg recovery experiments on a variety of biological matrixes with different spiking substances and again showed good analytical characteristics (overall average recoveries = 98 {plus_minus} 5.1% for seafood and 100 {plus_minus} 3.6 for protein-rich baby foods). 22 refs., 1 fig., 5 tabs.

  15. Development and validation of a radioimmunoassay for fish insulin-like growth factor I (IGF-I) and the effect of aquaculture related stressors on circulating IGF-I levels.

    PubMed

    Dyer, Anthony R; Upton, Zee; Stone, David; Thomas, Philip M; Soole, Kathleen L; Higgs, Naomi; Quinn, Kirsty; Carragher, John F

    2004-02-01

    This paper describes the development and validation of a commercially available radioimmunoassay (RIA) for the detection of fish insulin-like growth factor-I (IGF-I). The assay was developed using recombinant barramundi IGF-I as antigen and recombinant tuna IGF-I as radiolabelled tracer and standard. Assay sensitivity was 0.15 ng/ml, inter-assay variation was 16% (n = 9) and intra-assay variation was 3% (n = 10). Cross reactivity of less than 0.01% was found with salmon insulin, salmon IGF-II and barramundi IGF-II, less than 0.5% with human IGF-I and less than 1% with human IGF-II. Parallel dose-response inhibition curves were shown for barramundi (Lates calcarifer), coho salmon (Oncorhynchus kisutch), Southern Bluefin tuna (Thunnus maccoyii), tilapia (Oreochromis mossambicus), and seabream (Pagrus auratus) IGF-I. The assay was then used to measure stress related changes in different aquacultured fish species. Salt water acclimated Atlantic salmon smolts (Salmo salar) bathed for 2 h in fresh water showed significantly lower IGF-I concentrations than control smolts two days after the bath (53.1 compared to 32.1 ng/ml), with levels of IGF-I also lower in smolts exhibiting stunted growth (stunts). Capture and confinement of wild tuna in sea-cages resulted in a significant decrease in IGF-I levels (28 ng/ml) when compared to tuna captured and sampled immediately (48 ng/ml), but had recovered to starting levels after 3 weeks (43 ng/ml). Handling and isolation in silver perch (Bidyanus bidyanus) led to a gradual decline in IGF-I over a 12 h period (36-19 ng/ml) but showed signs of recovery by 24 h (24 ng/ml) and had recovered fully 72 h after treatment (40 ng/ml). A similar trial in black bream (Acanthopagrus butcherii) showed comparable results with IGF-I levels gradually decreasing (40-26 ng/ml) over 24 h, results that were mirrored by cortisol concentrations which increased during this time (1-26 ng/ml). In the studies presented here changes in IGF-I levels were not

  16. Mercury in fish available in supermarkets in Illinois: are there regional differences.

    PubMed

    Burger, Joanna; Gochfeld, Michael

    2006-08-31

    Media coverage has made the public aware of both the benefits and the risks from eating self-caught fish, but information on contaminants in commercial fish is much more limited, especially on a local level. The U.S. Food and Drug Administration website provides methylmercury data for a variety of fish, but for many species sample sizes are small and data are more than a decade old, whereas commercial fish sources are highly dynamic. A few state agencies are beginning to provide contaminant information for commercial fish, including canned tuna. We examined the mercury concentration of six types of fish purchased in supermarkets in Chicago, Illinois in 2005. We measured total mercury (methylmercury accounts for about 90% of the total mercury in fish). One key question was whether the concentrations of mercury in fish available locally were similar to those reported in other areas of the country and in the FDA U.S. national data base. Such information is critical for the public, especially pregnant women or those planning on pregnancy, making decisions about types and quantities of fish to consume. Some fish are available generally throughout the U.S., but others are more locally available, suggesting a need for site-specific information. This research was stakeholder driven, and reflected local interest in the safety of local fish. There were significant differences in mercury concentrations among the fish, ranging from a mean of 0.03 microg/g (ppm-wet weight) for salmon (Salmo spp.) to 1.41 ppm for swordfish (Xiphias gladius). Maximum values for three species of fish (orange roughy Hoplostethus atianticus, swordfish walleye Sander vitreus) were over 1 ppm (FDA action level), and all of the fish except salmon had some values above 0.5 ppm, the action level set by some states and countries. There were significant differences in mercury concentrations among three types of canned tuna (Thunnus spp): "gourmet tuna" had the least amount of mercury, and white tuna had

  17. 78 FR 69822 - Proposed Information Collection; Comment Request; Pacific Tuna Fisheries Logbook

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-21

    ... assessments and other research concerning the fishery. If the data were not collected or if erroneous data... overfishing or inadequate management of the fishery. II. Method of Collection Vessel operators maintain bridge... submission. Affected Public: Individuals or households, business or other for profit organizations....

  18. Nisin Migration in Shelf Stable, Tuna-Filled Tortillas During Storage

    DTIC Science & Technology

    2014-09-22

    including Staphylococcus, Clostridium, Bacillus and Listeria (Abdollahzadeh, 2013; Muller, 2008; Pinto, 2011; Rajkovic, 2005; Richardson, 2011; Wijnker...Debevere J. 2005. Antimicrobial effect of nisin and carvacrol and competition between Bacillus cereus and Bacillus circulans in vacuum-packed potato

  19. 77 FR 44161 - Atlantic Highly Migratory Species; 2012 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-27

    ... information about the Deepwater Horizon/BP oil spill and alleged illegal fishing on the eastern Atlantic and... the effects of the Deepwater Horizon/BP oil spill and the effects of mixing of eastern and western BFT... of the Center's comment that are relevant to this rulemaking. Deepwater Horizon/BP Oil Spill In...

  20. 76 FR 60790 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-30

    ... continuation of that closure period in 2012 and 2013; (2) continuation of the high seas time/area purse seine... fishing vessels operating in the Convention Area to keep watch for drifting data buoys at sea and to take... releases of oceanic whitetip sharks with indication of status (dead or alive) and report it to the...

  1. 75 FR 79309 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-20

    ... inches (185 cm) CFL) or greater per vessel per day/trip. This default retention limit applies to General... limit to two large medium or giant BFT, measuring 73 inches CFL or greater, per vessel per...

  2. 76 FR 68332 - International Fisheries; Pacific Tuna Fisheries; Fishing Restrictions in the Eastern Pacific Ocean

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-04

    ... metric tons carrying capacity or greater) in 2011 from 73 days, which was established under Resolution C... metric tons carrying capacity) from fishing in the Convention Area from November 7, 2011, to January 18... listed on the IATTC Vessel Register; five are class size 6 (greater than 363 mt carrying capacity),...

  3. 76 FR 283 - International Fisheries; Pacific Tuna Fisheries; Vessel Capacity Limit in the Purse Seine Fishery...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-04

    ... of carrying capacity in the purse seine fleet. (2) All purse seine vessels, regardless of size, must... class size 5 and under (363 cubic meter carrying capacity or less) that primarily fish for coastal..., instead of weight, in metric tons, to measure the carrying capacities of vessels. Because a well can...

  4. 75 FR 41995 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-20

    ... (185 cm) curved fork length or greater) north of 39 18' N. lat. (off Great Egg Inlet, NJ) is prohibited... area, i.e., north of 39 18' N. lat. (off Great Egg Inlet, NJ) by vessels permitted in the HMS...

  5. 78 FR 48860 - Proposed Information Collection; Comment Request; South Pacific Tuna Act

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-12

    ... capability and financial responsibility of a vessel operator interested in participating in the Treaty... by the FFA, are used as an enforcement tool. If the information is not collected, the U.S....

  6. 76 FR 74003 - Atlantic Highly Migratory Species; Adjustments to the Atlantic Bluefin Tuna General and Harpoon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-30

    ... negative social and economic impacts outweigh the positive impacts and because NMFS believes the topic of... limit of two large medium BFT. The status quo alternative could result in negative economic impacts to... the potential negative ecological impact of a relatively large potential increase in large medium...

  7. Computational Fluid Dynamics of the Boundary Layer Characteristics of a Pacific Bluefin Tuna

    DTIC Science & Technology

    2015-09-18

    Underwater Vehicle CAD Computer-Aided Design CFD Computational Fluid Dynamics FEA Finite Element Analysis IGES Initial Graphics Exchange...finite element analysis ( FEA ) solvers, but in recent years it has made strides in improving its CFD meshing capabilities. While some CAD software

  8. 76 FR 18416 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... actions are being taken consistent with the BFT fishery management objectives of the 2006 Consolidated HMS Fishery Management Plan and to prevent overharvest of the 2011 Angling category quota. DATES: Effective... U.S.C. 971 et seq.) and the Magnuson-Stevens Fishery Conservation and Management Act...

  9. 77 FR 21015 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-09

    ... fishery management objectives of the 2006 Consolidated HMS Fishery Management Plan (Consolidated HMS FMP... the adjustment on accomplishing the objectives of the fishery management plan; Variations in seasonal... (16 U.S.C. 971 et seq.) and the Magnuson-Stevens Fishery Conservation and Management Act...

  10. 75 FR 33531 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-14

    ... BFT fishery management objectives of the 2006 Consolidated HMS Fishery Management Plan and to prevent... overfishing; effects of the adjustment on accomplishing the objectives of the fishery management plan... the Magnuson-Stevens Fishery Conservation and Management Act (Magnuson- Stevens Act; 16 U.S.C. 1801...

  11. 78 FR 2273 - Canned Tuna Deviating From Identity Standard; Temporary Permit for Market Testing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-10

    ... INFORMATION CONTACT: Loretta A. Carey, Center for Food Safety and Applied Nutrition (HFS-820), Food and Drug..., and Cosmetic Act (21 U.S.C. 341). ] The permit covers limited interstate marketing tests of products... panels on the labels of the test products must bear nutrition labeling in accordance with 21 CFR...

  12. 78 FR 21584 - Atlantic Highly Migratory Species; 2013 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-11

    ... transparency than year-end accounting would. If the complete 2012 landings information and final dead discard... current regulations to account for the total amount of dead discards until the end of the fishing season... maximum flexibility in accounting for landings and dead discards at the end of the year. In 2012, when...

  13. 77 FR 15712 - Atlantic Highly Migratory Species; 2012 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-16

    .... Comments sent by any other method, to any other address or individual, or received after the end of the... indicates an underharvest of the 2011 adjusted BFT quota. Final 2011 landings and dead discard information... meeting, ICCAT recommended a TAC of 1,750 mt annually for 2011 and for 2012, inclusive of dead...

  14. 76 FR 69137 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-08

    ... subsequent rulemaking. The 2011 BFT fishing year began on January 1, 2011, and ends December 31, 2011. The... under the particular category quota to harvest the additional amount of BFT before the end of the... will need to account for 2011 BFT landings and dead discards within the U.S. quota, consistent...

  15. 75 FR 74640 - International Fisheries; South Pacific Tuna Fisheries; Procedures To Request Licenses and a...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-01

    ... licenses in the event more applications are received than there are licenses available. Such an allocation... establish a system of allocating Treaty licenses in the event more applications are received than there are... licenses or imposes other management measures in the fishery. The ANPR also solicited comments and input...

  16. 76 FR 71469 - Western and Central Pacific Fisheries for Highly Migratory Species; 2011 Bigeye Tuna Longline...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-18

    ... in the western and central Pacific Ocean as a result of the fishery reaching the 2011 catch limit... in the western and central Pacific Ocean is managed, in part, under the Western and Central Pacific... Western and Central Pacific Ocean (Convention Area). NMFS monitored the retained catches of bigeye...

  17. 75 FR 68725 - Western and Central Pacific Fisheries for Highly Migratory Species; 2010 Bigeye Tuna Longline...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-09

    ... in the western and central Pacific Ocean as a result of the fishery reaching the 2010 catch limit... the western and central Pacific Ocean is managed, in part, under the Western and Central Pacific... Western and Central Pacific Ocean (Convention Area). NMFS monitored the retained catches of bigeye...

  18. 76 FR 39808 - International Fisheries; Pacific Tuna Fisheries; Recommendations Adopted by the Inter-American...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-07

    ... quota in the longline fishery for vessels over 24 meters in length from 2011-2013; and (3) renewal of... retained on board and landed, except fish deemed unfit for human consumption for reasons other than...

  19. 77 FR 19175 - Atlantic Highly Migratory Species; 2012 Atlantic Bluefin Tuna Quota Specifications

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-30

    ... public hearings in Gloucester, MA, and Silver Spring, MD, in order to provide greater opportunity for... Gloucester, MA, and a hearing will be held on April 10, 2012, from 2:30 to 4 p.m. in Silver Spring, MD... Drive, Gloucester, MA 01930. 2. Silver Spring, MD--NMFS Science Center, 1301 East-West Highway,...

  20. 77 FR 3637 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries; General Category Fishery

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-25

    ...; closure. SUMMARY: NMFS closes the General category fishery for large medium and giant Atlantic bluefin.... Therefore, through May 31, 2012, fishing for, retaining, possessing, or landing large medium or giant BFT by... BFT fishery before landings of large medium and giant BFT exceed the available subquota....

  1. 76 FR 44834 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries; Northern Area Trophy Fishery

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... closes the northern area Angling category fishery for large medium and giant (``trophy'') Atlantic... 2011 Angling category northern area subquota for large medium and giant BFT. DATES: Effective 11:30 p.m... quota of 1.4 mt of large medium and giant BFT (measuring 73 inches curved fork length or greater) to...

  2. 78 FR 11788 - Atlantic Highly Migratory Species; Atlantic Bluefin Tuna Fisheries; General Category Fishery

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-20

    ...; closure. SUMMARY: NMFS closes the General category fishery for large medium and giant Atlantic bluefin..., retaining, possessing, or landing large medium or giant BFT by persons aboard vessels permitted in the... large medium and giant BFT exceed the available subquota. Therefore, the AA finds good cause under 5...

  3. Human exposure to mercury, lead and cadmium through consumption of canned mackerel, tuna, pilchard and sardine.

    PubMed

    Okyere, H; Voegborlo, R B; Agorku, S E

    2015-07-15

    Total mercury (Hg), cadmium (Cd) and lead (Pb) concentrations were determined in canned fish on the Ghanaian market. Total mercury was determined using an automatic mercury analyzer while cadmium and lead levels were determined by flame atomic absorption spectrophotometry. The metal contents in the samples, expressed in μg g(-1) (wet weight), varied from <0.01 to 0.20 with an average value of 0.03 for mercury, from <0.01 to 0.45 with an average value of 0.34 for cadmium, and from <0.01 to 1.44 with an average value of 0.72 for lead. The results indicate that canned fish from the Ghanaian market have concentrations well below the permissible FAO/WHO for these toxic metals. Thus considering the Provisional Tolerable Weekly Intake (PTWI) of Hg, Pb and Cd the levels obtained in this study are unlikely to constitute a significant exposure to the public through consumption of moderate amounts.

  4. Fish Manoeuvres and Morphology

    NASA Astrophysics Data System (ADS)

    Singh, Kiran; Pedley, Timothy

    2008-11-01

    The extraordinary manoeuvrability observed in many fish is attributed to their inherent flexibility, which might be enhanced by the use of appendages like fins. The aim of this work is to understand the role of morphological adaptations, such as body shape and deployment of median fins, on manoeuvrability and internal body dynamics. The 3d vortex lattice numerical method was employed to analyse the hydrodynamics for arbitrary body planforms of infinitesimal thickness. The internal structure of the body due to the combined skeletal system and soft tissue, is represented as an active Euler-Bernoulli beam, in which the time-dependent bending moment distribution is calculated from body inertia and the hydrodynamic pressure difference across the body. C-turns are the manoeuvre of choice for this work and the response for three different species of fish are examined. Angelfish(Pterophyllum eimekei), pike (Esox sp) and tuna (Thunnus albacares) were chosen for their differences in body profile, median fin use and manoeuvrability. Net direction change and bending moment response to prescribed backbone flexure are calculated and used to interpret the influence of body profile on manoeuvrability and muscle work done. Internal stresses may be computed from anatomical data on muscle fibre distribution and recruitment. To the future, it is intended to extend this work to other typical manoeuvres, such as fast starts for which muscle activation patterns have been measured quite widely.

  5. Cloning and expression analysis of vasa during the reproductive cycle of Korean rockfish, Sebastes schlegeli

    NASA Astrophysics Data System (ADS)

    Mu, Weijie; Wen, Haishen; He, Feng; Li, Jifang; Liu, Miao; Ma, Ruiqin; Zhang, Yuanqing; Hu, Jian; Qi, Baoxia

    2013-03-01

    Vasa, which is a conserved member of the DEAD-box protein family, plays an indispensable role in primordial germ cell proliferation. However, the expression of vasa gene during the reproductive cycle in ovoviviparous fish has not been documented. In this study, the full-length sequence of vasa was obtained from the ovary of Korean rockfish ( Sebastes schlegeli) using reverse transcription-PCR and rapid amplification of cDNA ends. The Vasa with a mature protein of 650 amino acids showed greatest homology (84%) with giant gourami ( Osphronemus goramy) and Pacific bluefin tuna ( Thunnus orientalis). The expression of vasa mRNA in Korean rockfish was detected in gonads only, suggesting its specific role in gonadal development. In addition, seasonal changes in the vasa expression levels were examined in gonads by quantitative real-time PCR. The vasa transcript levels in adult testis were found higher during spermatogenesis than during spermiation. The vasa transcript levels remained relatively high at the early ovary stage but declined during ovary maturation in adult female fish. These results suggest that the vasa gene play an important role in spermatogenesis and early oogenesis during the reproductive cycle of Korean rockfish.

  6. Classifying movement behaviour in relation to environmental conditions using hidden Markov models.

    PubMed

    Patterson, Toby A; Basson, Marinelle; Bravington, Mark V; Gunn, John S

    2009-11-01

    1. Linking the movement and behaviour of animals to their environment is a central problem in ecology. Through the use of electronic tagging and tracking (ETT), collection of in situ data from free-roaming animals is now commonplace, yet statistical approaches enabling direct relation of movement observations to environmental conditions are still in development. 2. In this study, we examine the hidden Markov model (HMM) for behavioural analysis of tracking data. HMMs allow for prediction of latent behavioural states while directly accounting for the serial dependence prevalent in ETT data. Updating the probability of behavioural switches with tag or remote-sensing data provides a statistical method that links environmental data to behaviour in a direct and integrated manner. 3. It is important to assess the reliability of state categorization over the range of time-series lengths typically collected from field instruments and when movement behaviours are similar between movement states. Simulation with varying lengths of times series data and contrast between average movements within each state was used to test the HMMs ability to estimate movement parameters. 4. To demonstrate the methods in a realistic setting, the HMMs were used to categorize resident and migratory phases and the relationship between movement behaviour and ocean temperature using electronic tagging data from southern bluefin tuna (Thunnus maccoyii). Diagnostic tools to evaluate the suitability of different models and inferential methods for investigating differences in behaviour between individuals are also demonstrated.

  7. The influence of finfish aquaculture on benthic fish and crustacean assemblages in Fitzgerald Bay, South Australia

    PubMed Central

    Williams, Kane

    2015-01-01

    The influence of sea-cage aquaculture on wildfish assemblages has received little attention outside of Europe. Sea-cage aquaculture of finfish is a major focus in South Australia, and while the main species farmed is southern bluefin tuna (Thunnus maccoyii), there is also an important yellowtail kingfish (Seriola lalandi) industry. Yellowtail kingfish aquaculture did not appear to have any local or regional effects on demersal assemblages (primarily fish, but also some crustaceans) surveyed by baited remote underwater video (BRUV) in Fitzgerald Bay. We did, however, detect small scale spatial variations in assemblages within the bay. The type of bait used strongly influenced the assemblage recorded, with significantly greater numbers of fish attracted to deployments where sardines were used as the bait to compared to those with no bait. The pelleted feed used by the aquaculture industry was just as attractive as sardines at one site, and intermediate between sardines and no bait at the other. There was significant temporal variability in assemblages at both farm sites and one control site, while the second control site was temporally stable (over the 9 weeks of the study). Overall, the results suggested that aquaculture was having little if any impact on the abundance and assemblage structure of the demersal macrofauna in Fitzgerald Bay. PMID:26401452

  8. An aerobic scope-based habitat suitability index for predicting the effects of multi-dimensional climate change stressors on marine teleosts

    NASA Astrophysics Data System (ADS)

    Del Raye, Gen; Weng, Kevin C.

    2015-03-01

    Climate change will expose many marine ecosystems to temperature, oxygen and CO2 conditions that have not been experienced for millennia. Predicting the impact of these changes on marine fishes is difficult due to the complexity of these disparate stressors and the inherent non-linearity of physiological systems. Aerobic scope (the difference between maximum and minimum aerobic metabolic rates) is a coherent, unifying physiological framework that can be used to examine all of the major environmental changes expected to occur in the oceans during this century. Using this framework, we develop a physiology-based habitat suitability model to forecast the response of marine fishes to simultaneous ocean acidification, warming and deoxygenation, including interactions between all three stressors. We present an example of the model parameterized for Thunnus albacares (yellowfin tuna), an important fisheries species that is likely to be affected by climate change. We anticipate that if embedded into multispecies ecosystem models, our model could help to more precisely forecast climate change impacts on the distribution and abundance of other high value species. Finally, we show how our model may indicate the potential for, and limits of, adaptation to chronic stressors.

  9. Quantification of total and specific gram-negative histamine-producing bacteria species in fish using an MPN real-time PCR method.

    PubMed

    Bjornsdottir-Butler, Kristin; Jones, Jessica L; Benner, Ronald A; Burkhardt, William

    2011-10-01

    Quantification of histamine-producing bacteria (HPB) is necessary in order to elucidate the role that HPB play in scombrotoxin (histamine) fish poisoning. We report here the evaluation of a real-time PCR method for the quantification of total and specific Gram-negative HPB species in fish using a most probable number (MPN) format. The species-specific real-time PCR assay was 100% inclusive for independently detecting Morganella morganii, Enterobacter aerogenes, Raoultella planticola/ornithinolytica and Photobacterium damselae and did not cross react with other histamine- or non- histamine-producing bacteria. The efficiency of the reactions in the absence and presence of Spanish mackerel enrichment containing 1 × 10(6) CFU/ml of background microflora were 93-104 and 92-99%, respectively. The MPN-real-time PCR assay accurately quantified total and specific HPB in spiked mahi-mahi (Coryphaena hippurus) and Spanish mackerel (Scomberomorus maculates) samples. These methods were used to quantify total and specific HPB in naturally contaminated, decomposing mahi-mahi, Spanish mackerel and tuna (Thunnus albacares) samples. The results of this study indicate that MPN-real-time PCR assays can be used to accurately enumerate total and specific HPB in fish samples. These assays can be applied to assess the effectiveness of mitigation strategies and understand the relationship between HPB and histamine production in decomposing fish.

  10. Comparative metabolic rates of common western North Atlantic Ocean sciaenid fishes.

    PubMed

    Horodysky, A Z; Brill, R W; Bushnell, P G; Musick, J A; Latour, R J

    2011-07-01

    The resting metabolic rates (R(R)) of western North Atlantic Ocean sciaenids, such as Atlantic croaker Micropogonias undulatus, spot Leiostomus xanthurus and kingfishes Menticirrhus spp., as well as the active metabolic rates (R(A)) of M. undulatus and L. xanthurus were investigated to facilitate inter and intraspecific comparisons of their energetic ecology. The R(R) of M. undulatus and L. xanthurus were typical for fishes with similar lifestyles. The R(R) of Menticirrhus spp. were elevated relative to those of M. undulatus and L. xanthurus, but below those of high-energy-demand species such as tunas Thunnus spp. and dolphinfish Coryphaena hippurus. Repeated-measures non-linear mixed-effects models were applied to account for within-individual autocorrelation and corrected for non-constant variance typical of noisy R(A) data sets. Repeated-measures models incorporating autoregressive first-order [AR(1)] and autoregressive moving average (ARMA) covariances provided significantly superior fits, more precise parameter estimates (i.e. reduced s.e.) and y-intercept estimates that more closely approximated measured R(R) for M. undulatus and L. xanthurus than standard least-squares regression procedures.

  11. A novel system for embryo-larval toxicity testing of pelagic fish: Applications for impact assessment of Deepwater Horizon crude oil.

    PubMed

    Stieglitz, John D; Mager, Edward M; Hoenig, Ronald H; Alloy, Matthew; Esbaugh, Andrew J; Bodinier, Charlotte; Benetti, Daniel D; Roberts, Aaron P; Grosell, Martin

    2016-11-01

    Key differences in the developmental process of pelagic fish embryos, in comparison to embryos of standard test fish species, present challenges to obtaining sufficient control survival needed to successfully perform traditional toxicity testing bioassays. Many of these challenges relate to the change in buoyancy, from positive to negative, of pelagic fish embryos that occurs just prior to hatch. A novel exposure system, the pelagic embryo-larval exposure chamber (PELEC), has been developed to conduct successful bioassays on the early life stages (ELSs; embryos/larvae) of pelagic fish. Using this unique recirculating upwelling system, it was possible to significantly improve control survival in pelagic fish ELS bioassays compared to commonly used static exposure methods. Results demonstrate that control performance of mahi-mahi (Coryphaena hippurus) embryos in the PELEC system, measured as percent survival after 96-hrs, significantly outperformed agitated static exposure and static exposure systems. Similar significant improvements in 72-hr control survival were obtained with yellowfin tuna (Thunnus albacares). The PELEC system was subsequently used to test the effects of photo-induced toxicity of crude oil to mahi-mahi ELSs over the course of 96-hrs. Results indicate a greater than 9-fold increase in toxicity of Deepwater Horizon (DWH) crude oil during co-exposure to ambient sunlight compared to filtered ambient sunlight, revealing the importance of including natural sunlight in 96-hr DWH crude oil bioassays as well as the PELEC system's potential application in ecotoxicological assessments.

  12. Potential toxicological hazard due to endocrine-disrupting chemicals on Mediterranean top predators: state of art, gender differences and methodological tools.

    PubMed

    Fossi, M C; Casini, S; Marsili, L

    2007-05-01

    Man-made endocrine-disrupting chemicals (EDCs) range across all continents and oceans. Some geographic areas are potentially more threatened than others: one of these is the Mediterranean Sea. Levels of some xenobiotics are much higher here than in other seas and oceans. In this paper we review the final results of a project supported by the Italian Ministry of the Environment, in which the hypothesis that Mediterranean top predator species (such as large pelagic fish and marine mammals) are potentially at risk due to EDCs was investigated. We illustrate the need to develop and apply sensitive methodological tools, such as biomarkers (Vitellogenin, Zona Radiata proteins and CYP1A activities) for evaluation of toxicological risk in large pelagic fish top predators (Swordfish, (Xiphias gladius), Bluefin Tuna (Thunnus thynnus thynnus)) and nondestructive biomarkers (CYP1A activities and fibroblast cell culture in skin biopsy), for the hazard assessment of threatened marine mammals species (Striped Dolphin, (Stenella coeruleoalba), Bottlenose Dolphin (Tursiops truncatus), Common Dolphin (Delphinus delphis) and Fin Whale (Balaenoptera physalus))exposed to EDCs. Differential gender susceptibility to EDCs is also explored both in large pelagic fish and in cetaceans. In cetaceans, male specimens showed higher cytochrome P450 induction (BPMO in skyn biopsies, CYP2B in fibroblasts cell cultures) by xenobiotics with respect to females.

  13. Potential toxicological hazard due to endocrine-disrupting chemicals on Mediterranean top predators: State of art, gender differences and methodological tools

    SciTech Connect

    Fossi, M.C. . E-mail: fossi@unisi.it; Casini, S.; Marsili, L.

    2007-05-15

    Man-made endocrine-disrupting chemicals (EDCs) range across all continents and oceans. Some geographic areas are potentially more threatened than others: one of these is the Mediterranean Sea. Levels of some xenobiotics are much higher here than in other seas and oceans. In this paper we review the final results of a project supported by the Italian Ministry of the Environment, in which the hypothesis that Mediterranean top predator species (such as large pelagic fish and marine mammals) are potentially at risk due to EDCs was investigated. We illustrate the need to develop and apply sensitive methodological tools, such as biomarkers (Vitellogenin, Zona Radiata proteins and CYP1A activities) for evaluation of toxicological risk in large pelagic fish top predators (Swordfish (Xiphias gladius), Bluefin Tuna (Thunnus thynnus thynnus)) and nondestructive biomarkers (CYP1A activities and fibroblast cell culture in skin biopsy), for the hazard assessment of threatened marine mammals species (Striped Dolphin, (Stenella coeruleoalba), Bottlenose Dolphin (Tursiops truncatus), Common Dolphin (Delphinus delphis) and Fin Whale (Balaenoptera physalus))exposed to EDCs. Differential gender susceptibility to EDCs is also explored both in large pelagic fish and in cetaceans. In cetaceans, male specimens showed higher cytochrome P450 induction (BPMO in skyn biopsies, CYP2B in fibroblasts cell cultures) by xenobiotics with respect to females.

  14. Amounts and compositional analysis of glycosaminoglycans in the tissue of fish.

    PubMed

    Arima, Kazuya; Fujita, Hiroyuki; Toita, Ryosuke; Imazu-Okada, Ayaka; Tsutsumishita-Nakai, Nao; Takeda, Naoko; Nakao, Yasuhiro; Wang, Hui; Kawano, Manami; Matsushita, Kenya; Tanaka, Haruna; Morimoto, Shin; Nakamura, Ayumi; Kitagaki, Masahiro; Hieda, Yuka; Hatto, Ryuya; Watanabe, Ayako; Yumura, Takeru; Okuhara, Takashi; Hayashi, Hiroki; Shimizu, Katsuhiko; Nakayama, Kiyoshi; Masuda, Shinya; Ishihara, Yukio; Yoshioka, Shunsuke; Yoshioka, Shinobu; Shirade, Seizo; Tamura, Jun-ichi

    2013-01-25

    We isolated GAGs from the inedible parts; head, skin, internal organs, fins, scales and spine, of atlantic mackerel (Scomber scombrus), japanese jack mackerel (Trachurus japonicus), pacific bluefin tuna (Thunnus orientalis), yellowfin sole (Limanda aspera), broadbanded thornyhead (Sebastolobus macrochir), golden threadfin bream (Nemipterus virgatus), and nile tilapia (Oreochromis niloticus). We also investigated deep-sea fish, eelpouts (Bothrocara hollandi, Lycodes toyamensis, and Lycodes nakamurae), rough snailfish (Careproctus trachysoma), and squids (Watasenia scintillans, Enoploteuthis chunii, and Berryteuthis magister). Enzymatic digestion of the GAGs enabled a compositional analysis of CS, DS, and HA including the sulfation patterns of CS and DS, as well as the amount of each GAG. The molecular weights and distributions of these GAGs were also examined. The amounts of GAGs contained in the tissues and CS/DS ratios differed remarkably among the fish. The dorsal fin of the yellowfin sole contained more than 1300mg of CS-DS per 100g of defatted-dry tissue. Although the fish generally contained A-type rich CS-DS, bottom fish and deep-sea fish often possessed C-type CS-DS in larger ratios. Squid characteristically had E-type CS-DS which was normally less common in fish except in cartilaginous fish. These analytical results had no relation to the biological classification.

  15. The influence of finfish aquaculture on benthic fish and crustacean assemblages in Fitzgerald Bay, South Australia.

    PubMed

    Tanner, Jason E; Williams, Kane

    2015-01-01

    The influence of sea-cage aquaculture on wildfish assemblages has received little attention outside of Europe. Sea-cage aquaculture of finfish is a major focus in South Australia, and while the main species farmed is southern bluefin tuna (Thunnus maccoyii), there is also an important yellowtail kingfish (Seriola lalandi) industry. Yellowtail kingfish aquaculture did not appear to have any local or regional effects on demersal assemblages (primarily fish, but also some crustaceans) surveyed by baited remote underwater video (BRUV) in Fitzgerald Bay. We did, however, detect small scale spatial variations in assemblages within the bay. The type of bait used strongly influenced the assemblage recorded, with significantly greater numbers of fish attracted to deployments where sardines were used as the bait to compared to those with no bait. The pelleted feed used by the aquaculture industry was just as attractive as sardines at one site, and intermediate between sardines and no bait at the other. There was significant temporal variability in assemblages at both farm sites and one control site, while the second control site was temporally stable (over the 9 weeks of the study). Overall, the results suggested that aquaculture was having little if any impact on the abundance and assemblage structure of the demersal macrofauna in Fitzgerald Bay.

  16. Cold-stable eye lens crystallins of the Antarctic nototheniid toothfish Dissostichus mawsoni Norman.

    PubMed

    Kiss, Andor J; Mirarefi, Amir Y; Ramakrishnan, Subramanian; Zukoski, Charles F; Devries, Arthur L; Cheng, Chi-Hing C

    2004-12-01

    The eye lenses of the Antarctic nototheniid fishes that inhabit the perennially freezing Antarctic seawater are transparent at -2 degrees C, whereas the cold-sensitive mammalian and tropical fish lenses display cold-induced cataract at 20 degrees C and 7 degrees C, respectively. No cold-cataract occurs in the giant Antarctic toothfish Dissostichus mawsoni lens when cooled to temperatures as low as -12 degrees C, indicating highly cold-stable lens proteins. To investigate this cold stability, we characterised the lens crystallin proteins of the Antarctic toothfish, in parallel with those of the sub-tropical bigeye tuna Thunnus obesus and the endothermic cow Bos taurus, representing three disparate thermal climes (-2 degrees C, 18 degrees C and 37 degrees C, respectively). Sizing chromatography resolved their lens crystallins into three groups, alpha/betaH, beta and gamma, with gamma crystallins being the most abundant (>40%) lens proteins in fish, in contrast to the cow lens where they comprise only 19%. The upper thermal stability of these crystallin components correlated with the body temperature of the species. In vitro chaperone assays showed that fish alpha crystallin can protect same-species gamma crystallins from heat denaturation, as well as lysozyme from DTT-induced unfolding, and therefore are small Heat Shock Proteins (sHSP) like their mammalian counterparts. Dynamic light scattering measured an increase in size of alphagamma crystallin mixtures upon heating, which supports formation of the alphagamma complex as an integral part of the chaperone process. Surprisingly, in cross-species chaperone assays, tuna alpha crystallins only partly protected toothfish gamma crystallins, while cow alpha crystallins completely failed to protect, indicating partial and no alphagamma interaction, respectively. Toothfish gamma was likely to be the component that failed to interact, as the supernatant from a cow alpha plus toothfish gamma incubation could chaperone cow

  17. Permanent genetic resources added to Molecular Ecology Resources Database 1 October 2010-30 November 2010.

    PubMed

    Agostini, Cecilia; Agudelo, P A; Bâ, K; Barber, P A; Bisol, Paolo Maria; Brouat, C; Burgess, Treena I; Calves, I; Carrillo Avila, Mauricio; Chow, S; Cordes, Lisa; Da Silva, D; Dalecky, A; De Meester, L; Doadrio, Ignacio; Dobigny, G; Duplantier, J M; Evison, Sophie E F; Ford, Rebecca; Fresneau, Dominique; Galetti, Pedro M; Gauthier, P; Geldof, S; Granjon, L; Guérin, F; St J Hardy, Giles E; Hernandez Escobar, Carlos; Hima, K; Hu, Juan; Huang, Luqi; Humeau, L; Jansen, B; Jaquemet, S; Jiang, Zhi-Qiang; Jung, Sung-Ju; Kim, Bong-Seok; Kim, Cheol-Hee; Kim, Jong-Oh; Lai, Choay-Hoong; Laroche, J; Lavergne, E; Lawton-Rauh, A; Le Corre, M; Leach, M M; Lee, Jehee; Leo, Audrey E; Lichtenzveig, Judith; Lin, Lin; Linde, Celeste C; Liu, Shu-Fang; Marino, Ilaria A M; McKeown, Niall J; Nohara, K; Oh, Myung-Joo; Okamoto, H; Oliver, Richard; Olivera Angel, Martha; Ornelas-García, Claudia Patricia; Orsini, L; Ostos Alfonso, Henry; Othman, A S; Papetti, Chiara; Patarnello, Tomaso; Pedraza-Lara, Carlos; Piller, Kyle R; Poteaux, Chantal; Requier, J-B; Roziana, M K; Semba, Y; Sembene, M; Shah, Ramisah M; Shahril, A R; Shao, Aijuan; Shaw, Paul W; Song, Liangke; Souza Ferreira, Ronara; Su, Yong-Quan; Suzuki, N; Tatard, C; Taylor, Katherine M; Taylor, Paul W J; Thiam, M; Valbuena, Ruben; Wang, He; Yang, Byung-Gyoo; Yuan, Qingjun; Zajonz, U; Zane, Lorenzo; Zhu, Ling; Zhuang, Zhi-Meng; Zulaiha, A R

    2011-03-01

    This article documents the addition of 277 microsatellite marker loci to the Molecular Ecology Resources Database. Loci were developed for the following species: Ascochyta rabiei, Cambarellus chapalanus, Chionodraco hamatus, Coptis omeiensis, Cynoscion nebulosus, Daphnia magna, Gerbillus nigeriae, Isurus oxyrinchus, Lates calcarifer, Metacarcinus magister, Oplegnathus fasciatus, Pachycondyla verenae, Phaethon lepturus, Pimelodus grosskopfii, Rotylenchulus reniformis, Scomberomorus niphonius, Sepia esculenta, Terapon jarbua, Teratosphaeria cryptica and Thunnus obesus. These loci were cross-tested on the following species: Austropotamobius italicus, Cambarellus montezumae, Cambarellus puer, Cambarellus shufeldtii, Cambarellus texanus, Chionodraco myersi, Chionodraco rastrospinosus, Coptis chinensis, Coptis chinensis var. brevisepala, Coptis deltoidea, Coptis teeta, Orconectes virilis, Pacifastacus leniusculus, Pimelodus bochii, Procambarus clarkii, Pseudopimelodus bufonius, Rhamdia quelen, Sepia andreana, Sepiella maindroni, Thunnus alalunga, Thunnus albacares, Thunnus maccoyii, Thunnus orientalis, Thunnus thynnus and Thunnus tonggol.

  18. 50 CFR 635.41 - Products denied entry.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... (b) All shipments of tuna or tuna-like species, or their products, in any form, harvested in the... tuna-like species, or their products, in any form, harvested in the ICCAT convention area by a fishing... denied entry into the United States. (d) All shipments of tuna or tuna-like species, placed in cages...

  19. Characteristics of Fishing Operations, Environment and Life History Contributing to Small Cetacean Bycatch in the Northeast Atlantic

    PubMed Central

    Brown, Susie; Reid, David; Rogan, Emer

    2014-01-01

    Fisheries bycatch is a key threat to cetacean species globally. Managing the impact requires an understanding of the conditions under which animals are caught and the sections of the population affected. We used observer data collected on an albacore tuna gillnet fishery in the northeast Atlantic, to assess operational and environmental factors contributing to bycatch of common and striped dolphins, using generalised linear models and model averaging. Life history demographics of the captured animals were also investigated. In both species, young males dominated the catch. The age ratio of common dolphins was significantly different from that estimated for the population in the region, based on life tables (G = 17.1, d.f. = 2, p = 0.002). Skewed age and sex ratios may reflect varying vulnerability to capture, through differences in behaviour or segregation in populations. Adult females constituted the second largest portion of the bycatch for both species, with potential consequences for population sustainability. Depth was the most important parameter influencing bycatch of both species and reflected what is known about common and striped dolphin habitat use in the region as the probability of catching common dolphins decreased, and striped dolphins increased, with increasing depth. Striped dolphin capture was similarly influenced by the extent to which operations were conducted in daylight, with the probability of capture increasing with increased operations in the pre-sunset and post-sunrise period, potentially driven by increased ability of observers to record animals during daylight operations, or by diurnal movements increasing contact with the fishery. Effort, based on net length and soak time, had little influence on the probability of capturing either species. Our results illustrate the importance of assessing the demographic of the animals captured during observer programmes and, perhaps more importantly, suggest that effort restrictions alone

  20. Simultaneous determination of perfluorinated compounds and their potential precursors in mussel tissue and fish muscle tissue and liver samples by liquid chromatography-electrospray-tandem mass spectrometry.

    PubMed

    Zabaleta, I; Bizkarguenaga, E; Prieto, A; Ortiz-Zarragoitia, M; Fernández, L A; Zuloaga, O

    2015-03-27

    An analytical method for the simultaneous determination in fish liver and muscle tissue and mussel samples of 14 perfluorinated compounds (PFCs), including three perfluoroalkylsulfonates (PFSAs), seven perfluorocarboxylic acids (PFCAs), three perfluorophosphonic acids (PFPAs) and perfluorooctanesulfonamide (PFOSA), and 10 potential precursors, including four polyfluoroalkyl phosphates (PAPs), four fluorotelomer saturated acids (FTCAs) and two fluorotelomer unsaturated acids (FTUCAs), was developed in the present work. Different clean-up strategies by means of solid-phase extraction (SPE) using a mix-mode weak anion exchanger (WAX), reverse phase Envi-Carb or a combination of them was optimized and evaluated for the clean-up of focused ultrasonic solid-liquid (FUSLE) extracts before the analysis by liquid chromatography-triple quadrupole tandem mass spectrometry (LC-MS/MS). Mix-mode WAX coupled in-line to Envi-Carb was finally selected since it rendered the cleanest extracts and minimum matrix effect. The FUSLE-SPE-LC-MS/MS methodology was validated in terms of recovery, precision and method detection limits (MDLs). Apparent recovery values in the 65-116%, 59-119% and 67-126% range and MDLs in the 0.1-2.7 ng/g, 0.1-3.8 ng/g and 0.2-3.1ng/g range were obtained for liver, mussel and fish muscle tissue samples, respectively. The method developed was applied to the analysis of grey mullet liver (Chelon labrosus) and mussel (Mytilus galloprovincialis) samples from the Basque Coast (North of Spain) and Yellowfin tuna muscle tissue (Thunnus albacares) samples from the Indian Ocean. To the best of our knowledge this is the first method that describes the simultaneous determination of 14 PFCs and 10 potential precursors in fish liver, fish muscle tissue and mussel samples. Besides, this is the first time that 8:2 monosubstituted polyfluorodecyl phosphate (8:2 monoPAP) and 8:2 disubstituted polyfluorodecyl phosphate (8:2 diPAP) were detected in mussel and tuna samples

  1. 50 CFR 216.24 - Taking and related acts incidental to commercial fishing operations by tuna purse seine vessels...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... status, either active or inactive, on the Vessel Register in § 300.22(b)(4) of this title. (C) The owner... training under paragraph (c)(5) of this section. The operator's permit is valid only when the permit holder... that a vessel in excess of 400 st (362.8 mt) carrying capacity be categorized as active on the...

  2. 75 FR 48941 - General Advisory Committee to the U.S. Section to the Inter-American Tropical Tuna Commission...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-12

    ... notify Heidi Hermsmeyer prior to September 10, 2010, of your plans to attend the meeting, or interest in a teleconference option. FOR FURTHER INFORMATION CONTACT: Heidi Hermsmeyer, Southwest Region, NMFS at Heidi.Hermsmeyer@noaa.gov , or at (562) 980-4036. SUPPLEMENTARY INFORMATION: In accordance...

  3. Viewpoints of high migratory tuna species ecology. Comment on ;Physics of metabolic organization; by M. Jusup et al.

    NASA Astrophysics Data System (ADS)

    Kitagawa, Takashi; Aoki, Yoshinori

    2017-03-01

    When discussing the evolution of fish migration, it is necessary to consider the total benefit fish acquire over their entire life history. With diadromous migration, for instance, some fish species migrate from freshwater and feed in the ocean (anadromous species), and others migrate from the ocean and feed in freshwater (catadromous). These contrasting directions of migration can largely be explained by the relative availability of food resources in ocean and freshwater habitats [1]. However, there are few examples that measure or quantify total energy as a concrete value that a single fish acquires through migration.

  4. 76 FR 18653 - Atlantic Highly Migratory Species; Bluefin Tuna Bycatch Reduction in the Gulf of Mexico Pelagic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-05

    ... economic impacts in the medium and long-term could result if no action is taken to address the incidental... GOM with minimal short-term negative socio-economic impacts; and have both short- and long-term beneficial impacts on the stock status of Atlantic BFT, an overfished species. This action affects...

  5. 50 CFR 216.24 - Taking and related acts incidental to commercial fishing operations by tuna purse seine vessels...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... (362.8 mt) carrying capacity that does not have a valid permit obtained under these regulations to... the ETP. The waiver will provide, in writing, the terms and conditions under which the vessel must... under paragraph (b) of this section. This permit is not transferable and must be renewed annually. If...

  6. 50 CFR 216.24 - Taking and related acts incidental to commercial fishing operations by tuna purse seine vessels...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... (362.8 mt) carrying capacity that does not have a valid permit obtained under these regulations to... the ETP. The waiver will provide, in writing, the terms and conditions under which the vessel must... under paragraph (b) of this section. This permit is not transferable and must be renewed annually. If...

  7. 50 CFR 216.24 - Taking and related acts incidental to commercial fishing operations by tuna purse seine vessels...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... (362.8 mt) carrying capacity that does not have a valid permit obtained under these regulations to... the ETP. The waiver will provide, in writing, the terms and conditions under which the vessel must... under paragraph (b) of this section. This permit is not transferable and must be renewed annually. If...

  8. 50 CFR 216.24 - Taking and related acts incidental to commercial fishing operations by tuna purse seine vessels...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (362.8 mt) carrying capacity that does not have a valid permit obtained under these regulations to... the ETP. The waiver will provide, in writing, the terms and conditions under which the vessel must... under paragraph (b) of this section. This permit is not transferable and must be renewed annually. If...

  9. 76 FR 2313 - Atlantic Highly Migratory Species; Bluefin Tuna Bycatch Reduction in the Gulf of Mexico Pelagic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-13

    ... than corrodible, non-stainless steel hooks. The final rule also required all HMS bottom and PLL vessels.... Note that the SCRS uses the abbreviation ``t'' for tons; it is equivalent to mt. ``State of the...

  10. Characterization of genes encoding prolactin and prolactin receptors in starry flounder Platichthys stellatus and their expression upon acclimation to freshwater.

    PubMed

    Noh, Gyeong Eon; Lim, Han Kyu; Kim, Jong-Myoung

    2013-04-01

    This study aims to investigate the genes encoding prolactin (PRL) and prolactin receptors (PRLR) and their tissue-specific expression in starry flounder Platichthys stellatus. Starry flounder PRL gene consisting of five exons encodes an ORF of 212 amino acid residue comprised of a putative signal peptide of 24 amino acids and a mature protein of 188 amino acids. It showed amino acid identities of 73 % with tuna Thunnus thynnus, 71 % with black porgy Acanthopagrus schlegelii, 69 % with Nile tilapia Oreochromis niloticus, 64 % with pufferfish Takifugu rubripes, 63 % with rainbow trout Oncorhynchus mykiss, and 60 % with mangrove rivulus Kryptolebias marmoratus. Phylogenetic analysis of piscine PRLs also demonstrated a similarity between starry flounder and other teleosts but with a broad distinction from non-teleost PRLs. PRLR gene consists of eight exons encoding a protein of 528 amino acid residues. It showed a similarity to the PRLR2 subtype as reflected by amino acid identities of 54 % with A. schlegelii, 48.1 % with K. marmoratus, 46.3 % with tilapia O. mossambicus, and 46.1 % with O. niloticus PRLR2 as compared to PRLR1 isoform having less than 30 % identities. While mRNA transcript corresponding to PRL was detected only from the pituitary, most of PRLR mRNA was detected in the gill, kidney, and intestine, with a small amount in the ovary. The level of PRL transcript progressively increased during 6 days of acclimation to freshwater and then decreased but stayed higher than that of seawater at 60 days of acclimation. An opposite pattern of changes including a decrease at the beginning of the acclimation but a slight increase in the level osmolality was found as adaptation continued. The results support the osmoregulatory role of PRL signaling in starry flounder.

  11. Inferring the nature of anthropogenic threats from long-term abundance records.

    PubMed

    Shoemaker, Kevin T; Akçakaya, H Resit

    2015-02-01

    Diagnosing the processes that threaten species persistence is critical for recovery planning and risk forecasting. Dominant threats are typically inferred by experts on the basis of a patchwork of informal methods. Transparent, quantitative diagnostic tools would contribute much-needed consistency, objectivity, and rigor to the process of diagnosing anthropogenic threats. Long-term census records, available for an increasingly large and diverse set of taxa, may exhibit characteristic signatures of specific threatening processes and thereby provide information for threat diagnosis. We developed a flexible Bayesian framework for diagnosing threats on the basis of long-term census records and diverse ancillary sources of information. We tested this framework with simulated data from artificial populations subjected to varying degrees of exploitation and habitat loss and several real-world abundance time series for which threatening processes are relatively well understood: bluefin tuna (Thunnus maccoyii) and Atlantic cod (Gadus morhua) (exploitation) and Red Grouse (Lagopus lagopus scotica) and Eurasian Skylark (Alauda arvensis) (habitat loss). Our method correctly identified the process driving population decline for over 90% of time series simulated under moderate to severe threat scenarios. Successful identification of threats approached 100% for severe exploitation and habitat loss scenarios. Our method identified threats less successfully when threatening processes were weak and when populations were simultaneously affected by multiple threats. Our method selected the presumed true threat model for all real-world case studies, although results were somewhat ambiguous in the case of the Eurasian Skylark. In the latter case, incorporation of an ancillary source of information (records of land-use change) increased the weight assigned to the presumed true model from 70% to 92%, illustrating the value of the proposed framework in bringing diverse sources of

  12. Locational differences in mercury and selenium levels in 19 species of saltwater fish from New Jersey.

    PubMed

    Burger, Joanna; Jeitner, Christian; Gochfeld, Michael

    2011-01-01

    Individuals who fish, and their families that ingest self-caught fish, make decisions about where to fish, what type of fish to eat, and the quantity of fish to eat. While federal and state agencies often issue consumption advisories for some fish with high mercury (Hg) concentrations, advisories seldom provide the actual metal levels to the general public. There are few data for most saltwater fish, and even less information on variations in Hg levels in fish within a state or geographical region. The objective of this study was to provide Hg concentrations from 19 species of fish caught in different locations in New Jersey to (1) test the hypothesis that mean metal levels vary geographically, (2) provide this information to individuals who fish these coastal waters, and (3) provide a range of values for risk assessors who deal with saltwater fish exposure in the Northeastern United States. Selenium (Se) was also examined because of its purported moderating effect on the toxicity of Hg. Hg levels showed significant geographical variation for 10 of 14 species that were caught in more than one region of New Jersey, but there were significant locational differences for Se in only 5 of the fish. Mercury levels were significantly lower in fish collected from northern New Jersey (except for ling, Molva molva), compared to other regions. As might be expected, locational differences in Hg levels were greatest for fish species with the highest Hg concentrations (shark, Isurus oxyrinchus; tuna, Thunnus thynnus and T. albacares; striped bass, Morone saxatilis; bluefish, Pomatomus saltatrix). Fishers and their families might reduce their risk from Hg exposure not only by selecting fish generally lower in Hg, but by fishing predominantly in some regions over others, further lowering the potential risk. Health professionals might use these data to advise patients on which fish are safest to consume (in terms of Hg exposure) from particular geographical regions.

  13. A Methodological Framework to Estimate the Site Fidelity of Tagged Animals Using Passive Acoustic Telemetry.

    PubMed

    Capello, Manuela; Robert, Marianne; Soria, Marc; Potin, Gael; Itano, David; Holland, Kim; Deneubourg, Jean-Louis; Dagorn, Laurent

    2015-01-01

    The rapid expansion of the use of passive acoustic telemetry technologies has facilitated unprecedented opportunities for studying the behavior of marine organisms in their natural environment. This technological advance would greatly benefit from the parallel development of dedicated methodologies accounting for the variety of timescales involved in the remote detection of tagged animals related to instrumental, environmental and behavioral events. In this paper we propose a methodological framework for estimating the site fidelity ("residence times") of acoustic tagged animals at different timescales, based on the survival analysis of continuous residence times recorded at multiple receivers. Our approach is validated through modeling and applied on two distinct datasets obtained from a small coastal pelagic species (bigeye scad, Selar crumenophthalmus) and a large, offshore pelagic species (yellowfin tuna, Thunnus albacares), which show very distinct spatial scales of behavior. The methodological framework proposed herein allows estimating the most appropriate temporal scale for processing passive acoustic telemetry data depending on the scientific question of interest. Our method provides residence times free of the bias inherent to environmental and instrumental noise that can be used to study the small scale behavior of acoustic tagged animals. At larger timescales, it can effectively identify residence times that encompass the diel behavioral excursions of fish out of the acoustic detection range. This study provides a systematic framework for the analysis of passive acoustic telemetry data that can be employed for the comparative study of different species and study sites. The same methodology can be used each time discrete records of animal detections of any nature are employed for estimating the site fidelity of an animal at different timescales.

  14. A Methodological Framework to Estimate the Site Fidelity of Tagged Animals Using Passive Acoustic Telemetry

    PubMed Central

    Capello, Manuela; Robert, Marianne; Soria, Marc; Potin, Gael; Itano, David; Holland, Kim; Deneubourg, Jean-Louis; Dagorn, Laurent

    2015-01-01

    The rapid expansion of the use of passive acoustic telemetry technologies has facilitated unprecedented opportunities for studying the behavior of marine organisms in their natural environment. This technological advance would greatly benefit from the parallel development of dedicated methodologies accounting for the variety of timescales involved in the remote detection of tagged animals related to instrumental, environmental and behavioral events. In this paper we propose a methodological framework for estimating the site fidelity (“residence times”) of acoustic tagged animals at different timescales, based on the survival analysis of continuous residence times recorded at multiple receivers. Our approach is validated through modeling and applied on two distinct datasets obtained from a small coastal pelagic species (bigeye scad, Selar crumenophthalmus) and a large, offshore pelagic species (yellowfin tuna, Thunnus albacares), which show very distinct spatial scales of behavior. The methodological framework proposed herein allows estimating the most appropriate temporal scale for processing passive acoustic telemetry data depending on the scientific question of interest. Our method provides residence times free of the bias inherent to environmental and instrumental noise that can be used to study the small scale behavior of acoustic tagged animals. At larger timescales, it can effectively identify residence times that encompass the diel behavioral excursions of fish out of the acoustic detection range. This study provides a systematic framework for the analysis of passive acoustic telemetry data that can be employed for the comparative study of different species and study sites. The same methodology can be used each time discrete records of animal detections of any nature are employed for estimating the site fidelity of an animal at different timescales. PMID:26261985

  15. LOCATIONAL DIFFERENCES IN MERCURY AND SELENIUM LEVELS IN 19 SPECIES OF SALTWATER FISH FROM NEW JERSEY

    PubMed Central

    Burger, Joanna; Jeitner, Christian; Gochfeld, Michael

    2014-01-01

    Individuals who fish, and their families that ingest self-caught fish, make decisions about where to fish, what type of fish to eat, and the quantity of fish to eat. While federal and state agencies often issue consumption advisories for some fish with high mercury (Hg) concentrations, advisories seldom provide the actual metal levels to the general public. There are few data for most saltwater fish, and even less information on variations in Hg levels in fish within a state or geographical region. The objective of this study was to provide Hg concentrations from 19 species of fish caught in different locations in New Jersey to (1) test the hypothesis that mean metal levels vary geographically, (2) provide this information to individuals who fish these coastal waters, and (3) provide a range of values for risk assessors who deal with saltwater fish exposure in the Northeastern United States. Selenium (Se) was also examined because of its purported moderating effect on the toxicity of Hg. Hg levels showed significant geographical variation for 10 of 14 species that were caught in more than one region of New Jersey, but there were significant locational differences for Se in only 5 of the fish. Mercury levels were significantly lower in fish collected from northern New Jersey (except for ling, Molva molva), compared to other regions. As might be expected, locational differences in Hg levels were greatest for fish species with the highest Hg concentrations (shark, Isurus oxyrinchus; tuna, Thunnus thynnus and T. albacares; striped bass, Morone saxatilis; bluefish, Pomatomus saltatrix). Fishers and their families might reduce their risk from Hg exposure not only by selecting fish generally lower in Hg, but by fishing predominantly in some regions over others, further lowering the potential risk. Health professionals might use these data to advise patients on which fish are safest to consume (in terms of Hg exposure) from particular geographical regions. PMID:21598171

  16. 50 CFR 300.180 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... recommendations of the International Commission for the Conservation of Atlantic Tunas (ICCAT) for the conservation and management of tuna and tuna-like species in the Atlantic Ocean and of the Inter-American.... The regulations in this subpart are issued under the authority of the Atlantic Tunas Convention Act...

  17. 50 CFR 300.180 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... recommendations of the International Commission for the Conservation of Atlantic Tunas (ICCAT) for the conservation and management of tuna and tuna-like species in the Atlantic Ocean and of the Inter-American.... The regulations in this subpart are issued under the authority of the Atlantic Tunas Convention Act...

  18. 76 FR 82180 - International Fisheries; Western and Central Pacific Fisheries for Highly Migratory Species...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-30

    ...; Western and Central Pacific Fisheries for Highly Migratory Species; Fishing Restrictions for Bigeye Tuna and Yellowfin Tuna in Purse Seine Fisheries for 2012 AGENCY: National Marine Fisheries Service (NMFS... Regulations To Implement WCPFC Decision for Bigeye Tuna and Yellowfin Tuna in Purse Seine Fisheries At...

  19. Aggregation Bifurcation, and Extinction in Exploited Animal Population.

    DTIC Science & Technology

    1978-03-01

    Mangel (1977), “On the Schooling Strategy of Tuna : Effects on Purse — Seine Fisheries,” Preprint. 3. .i.i . Cohen and R.M. Lewis (1967), A Ray Method...in the off-shore Eastern Tropical Tuna Fishery (e.g., IATTC, 1975). In this case, tuna associate with porpoise schoools. The fishery harvests only...those tuna associated with porpoise. Consequently , the underlying population of tuna is not sampled by the fishery. One may wonder what information

  20. 42. VIEW SHOWING A GROUP OF TRAINEES DURING 50LB PRESSURE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. VIEW SHOWING A GROUP OF TRAINEES DURING 50-LB PRESSURE TEST IN RECOMPRESSION CHAMBER IN EQUIPMENT HOUSE No date - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  1. 13. VIEW, LOOKING WEST FROM LEFT TO RIGHT, SHOWING HIGH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. VIEW, LOOKING WEST FROM LEFT TO RIGHT, SHOWING HIGH PRESSURE AIR FLASK ROOM AND PUMP ROOM - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  2. 44. TANK LOFT: PLANS, ELEVATIONS AND DETAILS, Y&D No. 107722 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. TANK LOFT: PLANS, ELEVATIONS AND DETAILS, Y&D No. 107722 Scales as indicated; July 2, 1929 - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  3. 34. VIEW OF SUBMARINE ESCAPE TRAINING TANK PRIOR TO ADDITION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. VIEW OF SUBMARINE ESCAPE TRAINING TANK PRIOR TO ADDITION OF BLISTERS IN 1959, LOOKING SOUTHEAST - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  4. 23. VIEW OF ESCAPE TRAINING TANK, LOOKING NORTHWEST, SHOWING TWOLOCK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. VIEW OF ESCAPE TRAINING TANK, LOOKING NORTHWEST, SHOWING TWO-LOCK RECOMPRESSION CHAMBER IN PASSAGEWAY FROM ELEVATOR TO CUPOLA - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  5. 16. INTERIOR VIEW OF SUBMARINE SECTION AT 110FOOT LEVEL, ESCAPE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. INTERIOR VIEW OF SUBMARINE SECTION AT 110-FOOT LEVEL, ESCAPE TRAINING TANK, SHOWING LADDER TO ESCAPE TANK, LOOKING SOUTH - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  6. 20. DETAIL VIEW IN 18FOOT LOCK, ESCAPE TRAINING TANK, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. DETAIL VIEW IN 18-FOOT LOCK, ESCAPE TRAINING TANK, SHOWING DOOR INTO TANK AT RIGHT - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  7. 10. VIEW, LOOKING NORTHWEST FROM LEFT TO RIGHT, SHOWING PUMP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW, LOOKING NORTHWEST FROM LEFT TO RIGHT, SHOWING PUMP ROOM AND DRESSING ROOM - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  8. 38. INTERIOR VIEW OF TANK. Suspended wooden platform obscures bottom ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    38. INTERIOR VIEW OF TANK. Suspended wooden platform obscures bottom of tank No date - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  9. 24. VIEW OF EQUIPMENT ROOM WITH TRIPLELOCK RECOMPRESSION CHAMBER, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. VIEW OF EQUIPMENT ROOM WITH TRIPLE-LOCK RECOMPRESSION CHAMBER, LOOKING SOUTHWEST - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  10. 14. DETAIL VIEW OF ESCAPE TRAINING TANK, SHOWING HOLDDOWN RODS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. DETAIL VIEW OF ESCAPE TRAINING TANK, SHOWING HOLD-DOWN RODS, LOOKING SOUTH - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  11. 28. VIEW OF OCTAGONAL SPREAD FOOTING AND HOLDDOWN RODS 1929, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. VIEW OF OCTAGONAL SPREAD FOOTING AND HOLD-DOWN RODS 1929, SUBMARINE ESCAPE TRAINING TANK - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  12. 15. VIEW OF ESCAPE TRAINING TANK, LOOKING EAST ACROSS MEZZANINE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. VIEW OF ESCAPE TRAINING TANK, LOOKING EAST ACROSS MEZZANINE, SHOWING ENTRANCE TO SUBMARINE SECTION AT 110-FOOT LEVEL - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  13. 21. VIEW OF ESCAPE TRAINING TANK, SHOWING INTERIOR OF CUPOLA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. VIEW OF ESCAPE TRAINING TANK, SHOWING INTERIOR OF CUPOLA AND TOP OF THE TANK, LOOKING NORTHEAST - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  14. 50. PIPING FOR SUBMARINE SECTION, Y&D No. 107728 Scale 3/8' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    50. PIPING FOR SUBMARINE SECTION, Y&D No. 107728 Scale 3/8' = 1'; August 26, 1929 - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  15. 12. VIEW, LOOKING SOUTH FROM LEFT TO RIGHT, SHOWING DRESSING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW, LOOKING SOUTH FROM LEFT TO RIGHT, SHOWING DRESSING FROM AND WORK/CHAMBER ROOM - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  16. 18. VIEW OF ESCAPE TRAINING TANK, SHOWING ENCLOSED PASSAGEWAY FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. VIEW OF ESCAPE TRAINING TANK, SHOWING ENCLOSED PASSAGEWAY FROM 50-FOOT LOCK TO ELEVATOR, LOOKING WEST - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  17. 17. VIEW OF ESCAPE TRAINING TANK, SHOWING ENCLOSED PASSAGEWAY FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. VIEW OF ESCAPE TRAINING TANK, SHOWING ENCLOSED PASSAGEWAY FROM ELEVATOR TO 18-FOOT LOCK, LOOKING EAST - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  18. 9. VIEW, LOOKING NORTH FROM LEFT TO RIGHT, SHOWING MEDICAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW, LOOKING NORTH FROM LEFT TO RIGHT, SHOWING MEDICAL RESEARCH LABORATORY ANNEX, EXAMINING ROOM, AND EQUIPMENT ROOM - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  19. Measurement of methyl mercury (I) and mercury (II) in fish tissues and sediments by HPLC-ICPMS and HPLC-HGAAS.

    PubMed

    Jagtap, Rajani; Krikowa, Frank; Maher, William; Foster, Simon; Ellwood, Michael

    2011-07-15

    A procedure for the extraction and determination of methyl mercury and mercury (II) in fish muscle tissues and sediment samples is presented. The procedure involves extraction with 5% (v/v) 2-mercaptoethanol, separation and determination of mercury species by HPLC-ICPMS using a Perkin-Elmer 3 μm C8 (33 mm×3 mm) column and a mobile phase 3 containing 0.5% (v/v) 2-mercaptoethanol and 5% (v/v) CH(3)OH (pH 5.5) at a flow rate 1.5 ml min(-1) and a temperature of 25°C. Calibration curves for methyl mercury (I) and mercury (II) standards were linear in the range of 0-100 μgl(-1) (r(2)=0.9990 and r(2)=0.9995 respectively). The lowest measurable mercury was 0.4 μgl(-1) which corresponds to 0.01 μgg(-1) in fish tissues and sediments. Methyl mercury concentrations measured in biological certified reference materials, NRCC DORM - 2 Dogfish muscle (4.4±0.8 μgg(-1)), NRCC Dolt - 3 Dogfish liver (1.55±0.09 μgg(-1)), NIST RM 50 Albacore Tuna (0.89±0.08 μgg(-1)) and IRMM IMEP-20 Tuna fish (3.6±0.6 μgg(-1)) were in agreement with the certified value (4.47±0.32μgg(-1), 1.59±0.12 μgg(-1), 0.87±0.03 μgg(-1), 4.24±0.27 μgg(-1) respectively). For the sediment reference material ERM CC 580, a methyl mercury concentration of 0.070±0.002 μgg(-1) was measured which corresponds to an extraction efficiency of 92±3% of certified values (0.076±0.04 μgg(-1)) but within the range of published values (0.040-0.084 μgg(-1); mean±s.d.: 0.073±0.05 μgg(-1), n=40) for this material. The extraction procedure for the fish tissues was also compared against an enzymatic extraction using Protease type XIV that has been previously published and similar results were obtained. The use of HPLC-HGAAS with a Phenomenox 5 μm Luna C18 (250 mm×4.6 mm) column and a mobile phase containing 0.06 moll(-1) ammonium acetate (Merck Pty Limited, Australia) in 5% (v/v) methanol and 0.1% (w/v) l-cysteine at 25°C was evaluated as a complementary alternative to HPLC-ICPMS for the measurement of

  20. A resolution expressing the sense of the Senate that, at the 21st Regular Meeting of the International Commission on the Conservation of Atlantic Tunas, the United States should seek to ensure management of the eastern Atlantic and Mediterranean bluefin tuna fishery adheres to the scientific advice provided by the Standing Committee on Research and Statistics and has a high probability of achieving the established rebuilding target, pursue strengthened protections for spawning bluefin populations in the Mediterranean Sea to facilitate the recovery of the Atlantic bluefin tuna, pursue imposition of more stringent measures to ensure compliance by all Members with the International Commission for the Conservation of Atlantic Tunas' conservation and management recommendations for Atlantic bluefin tuna and other species, and ensure that United States' quotas of tuna and swordfish are not reallocated to other nations, and for other purposes.

    THOMAS, 111th Congress

    Sen. Snowe, Olympia J. [R-ME

    2009-11-09

    11/09/2009 Submitted in the Senate, considered, and agreed to without amendment and with a preamble by Unanimous Consent. (consideration: CR S11301-11302; text as passed Senate: CR S11301-11302; text as introduced in Senate: CR S11293-11294) (All Actions) Tracker: This bill has the status Passed SenateHere are the steps for Status of Legislation: