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Cruz-Castán R, Saber S, Meiners-Mandujano C, Gómez Vives MJ, Curiel-Ramirez S, Galindo-Cortes G, Macías D. Oocyte dynamics for Atlantic bluefin tuna (Thunnus thynnus) in the southern Gulf of Mexico: A comparative assessment of Mediterranean spawners using two stereological methods. JOURNAL OF FISH BIOLOGY 2023; 103:1054-1072. [PMID: 37466346 DOI: 10.1111/jfb.15504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 07/09/2023] [Accepted: 07/17/2023] [Indexed: 07/20/2023]
Abstract
Although most research focused on the northern Gulf of Mexico for western Atlantic bluefin tuna, the histological records of reproductive activity of this species in the southern Gulf of Mexico (Mexican waters) have been presented for the first time. This work is the first to study oocyte dynamics in Atlantic bluefin tuna caught in the southern Gulf of Mexico by assessing and comparing them with Mediterranean stock (BFT-E) through stereology using two different methods. Regardless of Atlantic bluefin tuna females returning to their respective spawning grounds at different months in the southern Gulf of Mexico and the Mediterranean, both stocks arrived reproductively inactive and remained in these zones during periods of similar length; they were reproductively active until March for the southern Gulf of Mexico and May for the Mediterranean females. The comparison of the size structure between the two stocks examined using kernel density estimators demonstrated a quite remarkable difference in mean fork lengths between stocks. The ovarian oocyte density, that is, the number of oocytes per gram of ovary, for each gonad stage predicted using the Weibel and Gomez and oocyte packing density (OPD) methods did not significantly differ between stocks and showed that advanced vitellogenic oocytes from spawning-capable females are an appropriate indicator to estimate potential fecundity, presenting values of c. 1273 and ~1355 eggs per gram for the southern Gulf of Mexico and Mediterranean females, respectively. Females caught in Mexican waters (southern Gulf of Mexico) were larger than those caught in the Mediterranean; however, it was demonstrated that the length and weight of females did not affect ovarian oocyte density production. In addition, densities estimated for each gonad stage using W&G and OPD methods did not differ between stocks and presented equal patterns in their oocyte dynamics. These findings contribute to a better understanding of the reproductive biology of Atlantic bluefin tuna, especially in the southern Gulf of Mexico, due to the lack of information regarding this zone, and may allow to support strategies for proper assessment, management, and conservation.
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Affiliation(s)
- Roberto Cruz-Castán
- Posgrado en Ecología y Pesquerías, Universidad Veracruzana, Boca del Rio, Mexico
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Veracruzana, Veracruz, Mexico
| | - Sámar Saber
- Centro Oceanográfico de Murcia, Singular Scientific and Technical Infrastructure for the Bluefin Tuna Aquaculture (ICTS-ICAR), Instituto Español de Oceanografía (IEO-CSIC), Murcia, Spain
| | | | - María José Gómez Vives
- Centro Oceanográfico de Málaga, Instituto Español de Oceanografía (IEO-CSIC), Fuengirola, Spain
| | - Sergio Curiel-Ramirez
- Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Ensenada, Mexico
| | | | - David Macías
- Centro Oceanográfico de Málaga, Instituto Español de Oceanografía (IEO-CSIC), Fuengirola, Spain
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Andrews AJ, Orton D, Onar V, Addis P, Tinti F, Alexander M. Isotopic life-history signatures are retained in modern and ancient Atlantic bluefin tuna vertebrae. JOURNAL OF FISH BIOLOGY 2023. [PMID: 37185985 DOI: 10.1111/jfb.15417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 04/23/2023] [Indexed: 05/17/2023]
Abstract
Isotopic, tagging and diet studies of modern-day teleosts lack the ability to contextualise life-histories and trophic dynamics with a historical perspective, when exploitation rates were lower and climatic conditions differed. Isotopic analysis of vertebrae, the most plentiful hard-part in archaeological and museum collections, can potentially fill this data-gap. Chemical signatures of habitat and diet use during growth are retained by vertebrae during bone formation. However, to fulfil their potential to reveal life-history and trophic dynamics, we need a better understanding of the time-frame recorded by vertebrae, currently lacking due to a poor understanding of fish bone remodelling. To address this issue, we serially-sectioned four vertebral centra of the highly migratory Atlantic bluefin tuna (Thunnus thynnus; BFT) captured off Sardinia (Italy) and analysed their isotopic composition. We show how carbon (δ13 C), nitrogen (δ15 N) and sulfur (δ34 S) isotope values can vary significantly across BFT vertebrae growth-axes, revealing patterning in dietary life-histories. Further, we find similar patterns are revealed through incremental isotopic analysis of inner and outer vertebrae centra samples from thirteen archaeological BFT vertebrae dating between the 9th -13th century CE. Our results indicate that multi-year foraging signatures are retained in vertebrae and allow for the study of life-histories in both modern and paleo-environments. These novel methods can be extended across teleost taxa owing to their potential to inform management and conservation on how teleost trophic dynamics change over time and what their long-term environmental, ecological, and anthropological drivers are.
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Affiliation(s)
- Adam J Andrews
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Campus of Ravenna, Ravenna, Italy
| | - David Orton
- BioArCh, Department of Archaeology, University of York, York, U.K
| | - Vedat Onar
- Osteoarchaeology Practice and Research Centre and Faculty of Veterinary Medicine, Istanbul University-Cerrahpaşa, Istanbul, Turkey
| | - Piero Addis
- Department of Life and Environmental Sciences, University of Cagliari, Cagliari, Sardinia, Italy
| | - Fausto Tinti
- Department of Biological, Geological and Environmental Sciences, University of Bologna, Campus of Ravenna, Ravenna, Italy
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Low levels of sibship encourage use of larvae in western Atlantic bluefin tuna abundance estimation by close-kin mark-recapture. Sci Rep 2022; 12:18606. [PMID: 36329078 PMCID: PMC9633702 DOI: 10.1038/s41598-022-20862-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 09/20/2022] [Indexed: 11/05/2022] Open
Abstract
Globally, tunas are among the most valuable fish stocks, but are also inherently difficult to monitor and assess. Samples of larvae of Western Atlantic bluefin tuna Thunnus thynnus (Linnaeus, 1758) from standardized annual surveys in the northern Gulf of Mexico provide a potential source of "offspring" for close-kin mark-recapture (CKMR) estimates of abundance. However, the spatial patchiness and highly skewed numbers of larvae per tow suggest sampled larvae may come from a small number of parents, compromising the precision of CKMR. We used high throughput genomic profiling to study sibship within and among larval tows from the 2016 standardized Gulf-wide survey compared to targeted sampling carried out in 2017. Full- and half-siblings were found within both years, with 12% of 156 samples in 2016 and 56% of 317 samples in 2017 having at least one sibling. There were also two pairs of cross cohort half-siblings. Targeted sampling increased the number of larvae collected per sampling event but resulted in a higher proportion of siblings. The combined effective sample size across both years was about 75% of the nominal size, indicating that Gulf of Mexico larval collections could be a suitable source of juveniles for CKMR in Western Atlantic bluefin tuna.
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Importance of the Lunar Cycle on Mesopelagic Foraging by Atlantic Bluefin Tuna in the Upwelling Area of the Strait of Messina (Central Mediterranean Sea). Animals (Basel) 2022; 12:ani12172261. [PMID: 36077982 PMCID: PMC9454512 DOI: 10.3390/ani12172261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 08/28/2022] [Accepted: 08/29/2022] [Indexed: 11/29/2022] Open
Abstract
Simple Summary We investigated the influence of the lunar cycle on bluefin tuna prey composition in the Strait of Messina by stomach content analysis. We tested if the lunar phases could determine changes in mesopelagic prey composition and abundance. Moreover, we considered two potential impacts of the lunar cycle: the lunar irradiance and the strength of currents. These factors could affect availability of mesopelagic prey in upper waters of the study area. Mesopelagic fish and cephalopod prey were 60.7% of overall diet by number. In summary, the Strait of Messina has highly specific hydrodynamic and biological features which strongly depend on upwelling currents, which in turn are influenced by the lunar cycle (new and full moon with strong currents, quarters with fewer currents). Upwelling causes water mixing, bringing to the surface a large amount of mesopelagic fauna which become more readily available to tuna. Lunar irradiance contributes to the variation of prey composition, increasing the success of visual predation on mesopelagic resources at high light in the water column. Abstract The influence of the lunar cycle on bluefin tuna foraging in the upwelling area of the Strait of Messina was investigated by exploring trophic interaction with mesopelagic fish and cephalopod prey. To focus on how the lunar cycle could affect availability of mesopelagic prey for this predator, we tested potential differences in the diet related to each lunar phase. Moreover, we considered two potential impacts of the lunar cycle: the lunar irradiance and the strength of currents. Overall, 2672 prey items were mesopelagic fish and cephalopods, representing 60.7% of overall diet by number. The main mesopelagic fish prey items were lanternfishes and dragonfishes, while Onychoteuthis banksii was the most important cephalopod prey. In summary, the Strait of Messina has highly specific hydrodynamic and biological features which strongly depend on upwelling currents, which in turn are influenced by the lunar cycle (new and full moon with strong currents, quarters with fewer currents). Upwelling causes water mixing, bringing to the surface a large amount of mesopelagic fauna which become more readily available to tuna. Lunar irradiance contributes to the variation of prey composition, increasing the success of visual predation on mesopelagic resources at high light in the water column.
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Portner EJ, Snodgrass O, Dewar H. Pacific bluefin tuna, Thunnus orientalis, exhibits a flexible feeding ecology in the Southern California Bight. PLoS One 2022; 17:e0272048. [PMID: 36006923 PMCID: PMC9409590 DOI: 10.1371/journal.pone.0272048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 07/12/2022] [Indexed: 11/26/2022] Open
Abstract
Pacific bluefin tuna, Thunnus orientalis, migrates from spawning grounds in the western Pacific Ocean to foraging grounds in the California Current System (CCS), where they are thought to specialize on high energy, surface schooling prey. However, there has been substantial variability in estimates of forage availability in the CCS over the past two decades. To examine the foraging ecology of juvenile T. orientalis in the face this variability, we quantified the diet and prey energetics of 963 individuals collected in the Southern California Bight (SCB) from 2008 to 2016. Using classification and regression tree analysis, we observed three sampling periods characterized by distinct prey. In 2008, T. orientalis diet was dominated by midwater lanternfishes and enoploteuthid squids. During 2009–2014, T. orientalis consumed diverse fishes, cephalopods, and crustaceans. Only in 2015–2016 did T. orientalis specialize on relatively high energy, surface schooling prey (e.g. anchovy, pelagic red crab). Despite containing the smallest prey, stomachs collected in 2009–2014 had the highest number of prey and similar total energetic contents to stomachs collected in 2015–2016. We demonstrate that T. orientalis is an opportunistic predator that can exhibit distinct foraging behaviors to exploit diverse forage. Expanding our understanding of T. orientalis foraging ecology will improve our ability to predict its responses to changes in resource availability as well as potential impacts on the fisheries it supports.
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Affiliation(s)
- Elan J. Portner
- NOAA Southwest Fisheries Science Center, La Jolla, California, United States of America
- * E-mail:
| | - Owyn Snodgrass
- NOAA Southwest Fisheries Science Center, La Jolla, California, United States of America
| | - Heidi Dewar
- NOAA Southwest Fisheries Science Center, La Jolla, California, United States of America
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Payne MR, Danabasoglu G, Keenlyside N, Matei D, Miesner AK, Yang S, Yeager SG. Skilful decadal-scale prediction of fish habitat and distribution shifts. Nat Commun 2022; 13:2660. [PMID: 35551195 PMCID: PMC9098506 DOI: 10.1038/s41467-022-30280-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 04/25/2022] [Indexed: 11/11/2022] Open
Abstract
Many fish and marine organisms are responding to our planet's changing climate by shifting their distribution. Such shifts can drive international conflicts and are highly problematic for the communities and businesses that depend on these living marine resources. Advances in climate prediction mean that in some regions the drivers of these shifts can be forecast up to a decade ahead, although forecasts of distribution shifts on this critical time-scale, while highly sought after by stakeholders, have yet to materialise. Here, we demonstrate the application of decadal-scale climate predictions to the habitat and distribution of marine fish species. We show statistically significant forecast skill of individual years that outperform baseline forecasts 3-10 years ahead; forecasts of multi-year averages perform even better, yielding correlation coefficients in excess of 0.90 in some cases. We also demonstrate that the habitat shifts underlying conflicts over Atlantic mackerel fishing rights could have been foreseen. Our results show that climate predictions can provide information of direct relevance to stakeholders on the decadal-scale. This tool will be critical in foreseeing, adapting to and coping with the challenges of a changing future climate, particularly in the most ocean-dependent nations and communities.
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Affiliation(s)
- Mark R Payne
- Danish Meteorological Institute, Copenhagen, Denmark.
- National Institute of Aquatic Resources (DTU-Aqua), Technical University of Denmark, Kgs, Lyngby, Denmark.
| | | | - Noel Keenlyside
- Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
- Nansen Environmental and Remote Sensing Center, Bergen, Norway
| | - Daniela Matei
- Max Planck Institute for Meteorology, Hamburg, Germany
| | - Anna K Miesner
- Helmholtz-Zentrum Hereon, Institute of Coastal Systems - Analysis and Modeling, Geesthacht, Germany
| | - Shuting Yang
- Danish Meteorological Institute, Copenhagen, Denmark
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7
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A Comparison of Reproductive Performances in Young and Old Females: A Case Study on the Atlantic Bluefin Tuna in the Mediterranean Sea. Animals (Basel) 2021; 11:ani11123340. [PMID: 34944116 PMCID: PMC8697984 DOI: 10.3390/ani11123340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 11/15/2021] [Accepted: 11/18/2021] [Indexed: 12/23/2022] Open
Abstract
Simple Summary The Atlantic bluefin tuna Thunnus thynnus is a species characterized by complex trans-oceanic migrations linked to size, which rely on the delicate trade-off between somatic growth and reproduction before and during the migratory movements to reach spawning grounds. Therefore, understanding the processes that drive reproduction and elucidating its age-related regulation is essential in the context of sustainable fishery management. In this study, carried out in the Mediterranean Sea, older bluefin tuna females were found to have greater reproductive performances than younger females according to a molecular biology approach (i.e., gene expression), a result that likely mirrors a better physical condition, different habitat usage or migratory behaviour. This result highlights the importance of preserving large females for their major reproductive contribution at a stock level. Furthermore, the gonad-specific mir-202, which belongs to a class of non-coding RNA, called miRNA, that regulate the post-transcription of protein-coding genes, was identified as a potential candidate to play a role in egg quality and quantity (i.e., fecundity) during ovarian maturation through age- or stage-dependent reproductive processes. Overall, the present study contributes to improve the sustainability of the Atlantic bluefin tuna fishery in the Mediterranean Sea. Abstract In the Mediterranean Sea, a demographic substructure of the Atlantic bluefin tuna Thunnus thynnus has emerged over the last decade, with old and young individuals exhibiting different horizontal movements and spatial–temporal patterns of gonad maturation. In the present study, histology and molecular reproductive markers were integrated with the gonad-specific mir-202 gene expression and ovarian localization to provide a comprehensive picture of the reproductive performances in young and old females and investigate the role played by the mir-202 during gonadal maturation. During the reproductive period, old females (>100 kg; 194.6 ± 33.9 cm straight fork length; 11.3 ± 2.7 years old) were found to have greater reproductive performances than younger females (<80 kg; 139.3 ± 18.8 cm straight fork length; 8.4 ± 1.1 years old) according to gene expression results, suggesting a prolonged spawning season, earlier arrival on spawning grounds and/or better condition in older females. The mir-202-5p showed no global changes; it was abundantly expressed in granulosa cells and faintly present in the ooplasm. On the other hand, the mir-202-3p expression profile reflected levels of oocyte maturation molecular markers (star, lhr) and both histological and molecular (casp3) levels of follicular atresia. Overall, old females exhibited greater reproductive performances than younger females, likely reflecting different reproductive dynamics linked to the physical condition, habitat usage and migratory behaviour. These results highlight the importance of preserving large and old females in the context of fishery management. Finally, the mir-202 appears to be a good candidate to regulate the reproductive output of this species in an autocrine/paracrine manner through either stage- or age-dependent processes.
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8
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Strøm JF, Jensen JLA, Nikolopoulos A, Nordli E, Bjørn PA, Bøhn T. Sea trout Salmo trutta in the subarctic: home-bound but large variation in migratory behaviour between and within populations. JOURNAL OF FISH BIOLOGY 2021; 99:1280-1291. [PMID: 34184272 DOI: 10.1111/jfb.14832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Revised: 06/17/2021] [Accepted: 06/21/2021] [Indexed: 06/13/2023]
Abstract
Anadromous brown trout (sea trout), Salmo trutta, is currently in decline throughout its range, largely due to anthropogenic stressors in freshwater and marine habitats. Acoustic telmetry was utilized to study the marine migration of sea trout post-smolts from three populations in a relatively pristine subarctic fjord system. While at sea, the sea trout spent a substantial part of their time close to their natal river, preferred near shore over pelagic habitats and were strongly surface oriented. Despite a fidelity towards local areas, the sea trout utilized various parts of the fjord system, with maximum dispersion >30 km and total migration distance >300 km. Almost half of the sea trout (44%) migrated between river outlets, indicating that a metapopulation approach may be appropriate when managing neighbouring sea trout populations at high latitudes. Furthermore, the different populations displayed different migratory behaviours in terms of distance migrated, dispersion from origin and the likelihood of leaving their home area. This variation in migratory behaviour is likely influenced by spatiotemporal differences in habitat quality between sites, indicating that local habitat variations may promote population-specific behavioural responses even in relatively confined fjord systems.
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Affiliation(s)
| | | | | | - Eivind Nordli
- Faculty of Biosciences, Fisheries and Economics, UiT the Arctic University of Norway, Tromsø, Norway
| | | | - Thomas Bøhn
- Institute of Marine Research, Tromsø, Norway
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Davies TE, Carneiro AP, Tarzia M, Wakefield E, Hennicke JC, Frederiksen M, Hansen ES, Campos B, Hazin C, Lascelles B, Anker‐Nilssen T, Arnardóttir H, Barrett RT, Biscoito M, Bollache L, Boulinier T, Catry P, Ceia FR, Chastel O, Christensen‐Dalsgaard S, Cruz‐Flores M, Danielsen J, Daunt F, Dunn E, Egevang C, Fagundes AI, Fayet AL, Fort J, Furness RW, Gilg O, González‐Solís J, Granadeiro JP, Grémillet D, Guilford T, Hanssen SA, Harris MP, Hedd A, Huffeldt NP, Jessopp M, Kolbeinsson Y, Krietsch J, Lang J, Linnebjerg JF, Lorentsen S, Madeiros J, Magnusdottir E, Mallory ML, McFarlane Tranquilla L, Merkel FR, Militão T, Moe B, Montevecchi WA, Morera‐Pujol V, Mosbech A, Neves V, Newell MA, Olsen B, Paiva VH, Peter H, Petersen A, Phillips RA, Ramírez I, Ramos JA, Ramos R, Ronconi RA, Ryan PG, Schmidt NM, Sigurðsson IA, Sittler B, Steen H, Stenhouse IJ, Strøm H, Systad GHR, Thompson P, Thórarinsson TL, Bemmelen RS, Wanless S, Zino F, Dias MP. Multispecies tracking reveals a major seabird hotspot in the North Atlantic. Conserv Lett 2021. [DOI: 10.1111/conl.12824] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
| | | | | | - Ewan Wakefield
- Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow Glasgow U.K
| | | | | | | | - Bruna Campos
- EuroNatur Foundation Radolfzell Germany
- Stichting BirdLife Europe Brussels Belgium
| | | | | | | | | | | | | | - Loïc Bollache
- UMR 6249 Chrono‐environnement Université de Bourgogne Franche‐Comté Besançon France
- Groupe de Recherche en Ecologie Arctique Francheville France
| | - Thierry Boulinier
- Centre d'Ecologie Fonctionnelle et Evolutive CNRS ‐ Université de Montpellier ‐ Université Paul‐Valéry Montpellier – EPHE Montpellier France
| | - Paulo Catry
- MARE ‐ Marine and Environmental Sciences Centre ISPA ‐ Instituto Universitário Lisbon Portugal
| | - Filipe R. Ceia
- University of Coimbra, MARE‐Marine and Environmental Sciences Centre, Dep. Life Sciences Coimbra Portugal
| | - Olivier Chastel
- Centre d'Etudes Biologiques de Chizé (CEBC) UMR 7372 CNRS‐La Rochelle Université Villiers‐en‐bois France
| | | | - Marta Cruz‐Flores
- Institut de Recerca de la Biodiversitat (IRBio) and Dept. de Biologia Evolutiva, Ecologia i Ciències Ambientals Universitat de Barcelona Barcelona Spain
| | | | | | | | | | | | | | - Jérôme Fort
- Littoral, Environnement et Sociétés (LIENSs) UMR 7266 CNRS‐La Rochelle Université La Rochelle France
| | - Robert W. Furness
- Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow Glasgow U.K
| | - Olivier Gilg
- UMR 6249 Chrono‐environnement Université de Bourgogne Franche‐Comté Besançon France
- Groupe de Recherche en Ecologie Arctique Francheville France
| | - Jacob González‐Solís
- Institut de Recerca de la Biodiversitat (IRBio) and Dept. de Biologia Evolutiva, Ecologia i Ciències Ambientals Universitat de Barcelona Barcelona Spain
| | | | - David Grémillet
- Centre d'Etudes Biologiques de Chizé (CEBC) UMR 7372 CNRS‐La Rochelle Université Villiers‐en‐bois France
- FitzPatrick Institute of African Ornithology Rondebosch South Africa
| | | | | | | | - April Hedd
- Wildlife Research Division Environment and Climate Change Mount Pearl NL Canada
| | - Nicholas Per Huffeldt
- Department of Bioscience Aarhus University Roskilde Denmark
- Greenland Institute of Natural Resources Nuuk Greenland
| | - Mark Jessopp
- School of Biological, Earth & Environmental Sciences, Environmental Research Institute University College Cork Ireland
| | | | - Johannes Krietsch
- Friedrich Schiller University, Institute of Ecology and Evolution Jena Germany
- Max Planck Institute for Ornithology Department of Behavioural Ecology and Evolutionary Genetics Seewiesen Germany
| | - Johannes Lang
- Groupe de Recherche en Ecologie Arctique Francheville France
- Justus‐Liebig‐University Giessen, Clinic for Birds, Reptiles, Amphibians and Fish Working Group for Wildlife Research Giessen Germany
| | | | | | - Jeremy Madeiros
- Department of Environment and Natural Resources, Government of Bermuda Paget Bermuda
| | | | | | | | - Flemming R. Merkel
- Department of Bioscience Aarhus University Roskilde Denmark
- Greenland Institute of Natural Resources Nuuk Greenland
| | - Teresa Militão
- Institut de Recerca de la Biodiversitat (IRBio) and Dept. de Biologia Evolutiva, Ecologia i Ciències Ambientals Universitat de Barcelona Barcelona Spain
| | - Børge Moe
- Norwegian Institute for Nature Research Trondheim Norway
| | | | - Virginia Morera‐Pujol
- Institut de Recerca de la Biodiversitat (IRBio) and Dept. de Biologia Evolutiva, Ecologia i Ciències Ambientals Universitat de Barcelona Barcelona Spain
| | - Anders Mosbech
- Department of Bioscience Aarhus University Roskilde Denmark
| | - Verónica Neves
- MARE – Marine and Environmental Sciences Centre, IMAR & Okeanos Horta Portugal
| | | | - Bergur Olsen
- Faroe Marine Research Institute Tórshavn Faroe Islands
| | - Vitor H. Paiva
- University of Coimbra, MARE‐Marine and Environmental Sciences Centre, Dep. Life Sciences Coimbra Portugal
| | - Hans‐Ulrich Peter
- Friedrich Schiller University, Institute of Ecology and Evolution Jena Germany
| | | | | | | | - Jaime A. Ramos
- University of Coimbra, MARE‐Marine and Environmental Sciences Centre, Dep. Life Sciences Coimbra Portugal
| | - Raül Ramos
- Institut de Recerca de la Biodiversitat (IRBio) and Dept. de Biologia Evolutiva, Ecologia i Ciències Ambientals Universitat de Barcelona Barcelona Spain
| | - Robert A. Ronconi
- Canadian Wildlife Service, Environment and Climate Change Canada Dartmouth NS Canada
| | - Peter G. Ryan
- FitzPatrick Institute of African Ornithology Rondebosch South Africa
| | | | | | - Benoît Sittler
- Groupe de Recherche en Ecologie Arctique Francheville France
- University of Freiburg Freiburg Germany
| | | | | | | | | | - Paul Thompson
- Lighthouse Field Station, School of Biological Sciences University of Aberdeen Cromarty U.K
| | - Thorkell L. Thórarinsson
- Northeast Iceland Nature Research Centre Húsavík Iceland
- Icelandic Institute of Natural History Garðabær Iceland
| | | | | | | | - Maria P. Dias
- BirdLife International Cambridge U.K
- MARE ‐ Marine and Environmental Sciences Centre ISPA ‐ Instituto Universitário Lisbon Portugal
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Le-Alvarado M, Romo-Curiel AE, Sosa-Nishizaki O, Hernández-Sánchez O, Barbero L, Herzka SZ. Yellowfin tuna (Thunnus albacares) foraging habitat and trophic position in the Gulf of Mexico based on intrinsic isotope tracers. PLoS One 2021; 16:e0246082. [PMID: 33626056 PMCID: PMC7904200 DOI: 10.1371/journal.pone.0246082] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 01/12/2021] [Indexed: 11/20/2022] Open
Abstract
Yellowfin tuna (YFT, Thunnus albacares) is a commercially important species targeted by fisheries in the Gulf of Mexico (GM). Previous studies suggest a high degree of residency in the northern GM, although part of the population performs movements to southern Mexican waters. Whether YFT caught in southern waters also exhibit residency or migrate to the northern gulf is currently uncertain, and little is known regarding their trophic ecology. The isotopic composition (bulk & amino acids) of YFT muscle and liver tissues were compared to a zooplankton-based synoptic isoscape from the entire GM to infer feeding areas and estimate Trophic Position (TP). The spatial distribution of δ15Nbulk and δ15NPhe values of zooplankton indicated two distinct isotopic baselines: one with higher values in the northern GM likely driven by denitrification over the continental shelf, and another in the central-southern gulf, where nitrogen fixation predominates. Based on the contribution of the two regional isotopic baselines to YFT tissues, broad feeding areas were inferred, with a greater contribution of the northern GM (over a one-year time scale by muscle), and to a lesser extent in the central-southern GM (over the ca. 6-month scale by liver). This was corroborated by similarities in δ15NPhe values between YFT and the northern GM. TP estimates were calculated based on stable isotope analysis of bulk (SIA) and compound-specific isotope analysis (CSIA-AA) of the canonical source and trophic amino acids. Mean TP based on SIA was 4.9 ± 1.0 and mean TP based on CSIA-A was 3.9 ± 0.2. YFT caught within the Mexican region seem to feed in northern and in central and southern GM, while feeding in the northern GM has a temporal component. Thus, management strategies need to consider that YFT caught in US and Mexican waters are a shared binational resource that exhibit feeding migrations within the GM.
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Affiliation(s)
- Meliza Le-Alvarado
- Department of Biological Oceanography, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, México
| | - Alfonsina E. Romo-Curiel
- Department of Biological Oceanography, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, México
| | - Oscar Sosa-Nishizaki
- Department of Biological Oceanography, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, México
| | - Oscar Hernández-Sánchez
- Department of Biological Oceanography, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, México
| | - Leticia Barbero
- Ocean Chemistry and Ecosystems Division, Cooperative Institute for Marine and Atmospheric Studies (CIMAS), NOAA’s Atlantic Oceanographic and Meteorological Laboratory, Miami, Florida, United States of America
| | - Sharon Z. Herzka
- Department of Biological Oceanography, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California, México
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11
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Iverson AR, Fujisaki I, Lamont MM, Hart KM. Loggerhead sea turtle (Caretta caretta) diving changes with productivity, behavioral mode, and sea surface temperature. PLoS One 2019; 14:e0220372. [PMID: 31390354 PMCID: PMC6685635 DOI: 10.1371/journal.pone.0220372] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 07/15/2019] [Indexed: 11/29/2022] Open
Abstract
The relationship between dive behavior and oceanographic conditions is not well understood for marine predators, especially sea turtles. We tagged loggerhead turtles (Caretta caretta) with satellite-linked depth loggers in the Gulf of Mexico, where there is a minimal amount of dive data for this species. We tested for associations between four measurements of dive behavior (total daily dive frequency, frequency of dives to the bottom, frequency of long dives and time-at-depth) and both oceanographic conditions (sea surface temperature [SST], net primary productivity [NPP]) and behavioral mode (inter-nesting, migration, or foraging). From 2011-2013 we obtained 26 tracks from 25 adult female loggerheads tagged after nesting in the Gulf of Mexico. All turtles remained in the Gulf of Mexico and spent about 10% of their time at the surface (10% during inter-nesting, 14% during migration, 9% during foraging). Mean total dive frequency was 41.9 times per day. Most dives were ≤ 25 m and between 30-40 min. During inter-nesting and foraging, turtles dived to the bottom 95% of days. SST was an important explanatory variable for all dive patterns; higher SST was associated with more dives per day, more long dives and more dives to the seafloor. Increases in NPP were associated with more long dives and more dives to the bottom, while lower NPP resulted in an increased frequency of overall diving. Longer dives occurred more frequently during migration and a higher proportion of dives reached the seafloor during foraging when SST and NPP were higher. Our study stresses the importance of the interplay between SST and foraging resources for influencing dive behavior.
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Affiliation(s)
- Autumn R. Iverson
- Cherokee Nation Technologies, contracted to Wetland and Aquatic Research Center, United States Geological Survey, Davie, Florida, United States of America
| | - Ikuko Fujisaki
- Fort Lauderdale Research and Education Center, University of Florida, Davie, Florida, United States of America
| | - Margaret M. Lamont
- Wetland and Aquatic Research Center, United States Geological Survey, Gainesville, Florida, United States of America
| | - Kristen M. Hart
- Wetland and Aquatic Research Center, United States Geological Survey, Davie, Florida, United States of America
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12
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Ijima H, Jusup M, Takada T, Akita T, Matsuda H, Klanjscek T. Effects of environmental change and early-life stochasticity on Pacific bluefin tuna population growth. MARINE ENVIRONMENTAL RESEARCH 2019; 149:18-26. [PMID: 31146254 DOI: 10.1016/j.marenvres.2019.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 04/23/2019] [Accepted: 05/02/2019] [Indexed: 06/09/2023]
Abstract
Species conservation and fisheries management require approaches that relate environmental conditions to population-level dynamics, especially because environmental conditions shift due to climate change. We combined an individual-level physiological model and a conceptually simple matrix population model to develop a novel tool that relates environmental change to population dynamics, and used this tool to analyze effects of environmental changes and early-life stochasticity on Pacific bluefin tuna (PBT) population growth. We found that (i) currently, PBT population experiences a positive growth rate, (ii) somewhat surprisingly, stochasticity in early life survival increases this growth rate, (iii) sexual maturation age strongly depends on food and temperature, (iv) current fishing pressure, though high, is tolerable as long as the environment is such that PBT mature in less than 9 years of age (maturation age of up to 10 is possible in some environments), (v) PBT population growth rate is much more susceptible to changes in juvenile survival than changes in total reproductive output or adult survival. These results suggest that, to be effective, fishing regulations need to (i) focus on smaller tuna (i.e., juveniles and young adults), and (ii) mitigate adverse effects of climate change by taking into the account how future environments may affect the population growth.
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Affiliation(s)
- Hirotaka Ijima
- National Research Institute of Far Seas Fisheries, Shizuoka, 424-0902, Japan.
| | - Marko Jusup
- Tokyo Tech World Research Hub Initiative (WRHI), Institute of Innovative Research, Tokyo Institute of Technology, Tokyo, 152-8552, Japan
| | - Takenori Takada
- Graduate School of Environmental Science, Hokkaido University, Sapporo, 060-0810, Japan
| | - Tetsuya Akita
- National Research Institute of Fisheries Science, Yokohama, 236-8648, Japan
| | - Hiroyuki Matsuda
- Faculty of Environment and Information Sciences, Yokohama National University, Yokohama, 240-8501, Japan
| | - Tin Klanjscek
- Division for Marine and Environmental Research, Rudjer Bošković Institute, HR-10002, Zagreb, Croatia
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13
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Guiet J, Galbraith E, Kroodsma D, Worm B. Seasonal variability in global industrial fishing effort. PLoS One 2019; 14:e0216819. [PMID: 31100079 PMCID: PMC6524810 DOI: 10.1371/journal.pone.0216819] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Accepted: 04/29/2019] [Indexed: 11/18/2022] Open
Abstract
Human beings are the dominant top predator in the marine ecosystem. Throughout most of the global ocean this predation is carried out by industrial fishing vessels, that can now be observed in unprecedented detail via satellite monitoring of Automatic Identification System (AIS) messages. The spatial and temporal distribution of this fishing effort emerges from the coupled interaction of ecological and socio-economic drivers and can therefore yield insights on the dynamics of both the ecosystem and fishers. Here we analyze temporal variability of industrial fishing effort from 2015-2017 as recorded by global AIS coverage, and differentiated by fishing gear type. The strongest seasonal signal is a reduction of total deployed effort during the annual fishing moratorium on the numerically-dominant Chinese fleet, which occurs during boreal summer. An additional societally-controlled reduction of effort occurs during boreal winter holidays. After accounting for these societal controls, the total deployed effort is relatively invariant throughout the year for all gear types except squid jiggers and coastal purse seiners. Despite constant deployment levels, strong seasonal variability occurs in the spatial pattern of fishing effort for gears targeting motile pelagic species, including purse seiners, squid jiggers and longliners. Trawlers and fixed gears target bottom-associated coastal prey and show very little overall seasonality, although they exhibit more seasonal variation at locations that are further from port. Our results suggest that societal controls dominate the total deployment of fishing effort, while the behavior of pelagic fish, including seasonal migration and aggregation, is likely the most prominent driver of the spatial seasonal variations in global fishing effort.
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Affiliation(s)
- Jérôme Guiet
- Institut de Ciència i Tecnologia Ambientals (ICTA-UAB), Universitat Autònoma de Barcelona, Barcelona, Spain
- Department of Atmospheric and Oceanic Sciences, University of California Los Angeles, Los Angeles, California, United States of America
- * E-mail:
| | - Eric Galbraith
- Institut de Ciència i Tecnologia Ambientals (ICTA-UAB), Universitat Autònoma de Barcelona, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys, Barcelona, Spain
| | - David Kroodsma
- Global Fishing Watch, Washington DC, United States of America
| | - Boris Worm
- Biology Department, Dalhousie University, Halifax, Nova Scotia, Canada
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14
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Gleiss AC, Schallert RJ, Dale JJ, Wilson SG, Block BA. Direct measurement of swimming and diving kinematics of giant Atlantic bluefin tuna ( Thunnus thynnus). ROYAL SOCIETY OPEN SCIENCE 2019; 6:190203. [PMID: 31218059 PMCID: PMC6549966 DOI: 10.1098/rsos.190203] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/09/2019] [Indexed: 05/24/2023]
Abstract
Tunas possess a range of physiological and mechanical adaptations geared towards high-performance swimming that are of considerable interest to physiologists, ecologists and engineers. Advances in biologging have provided significant improvements in understanding tuna migrations and vertical movement patterns, yet our understanding of the locomotion and swimming mechanics of these fish under natural conditions is limited. We equipped Atlantic bluefin tuna (Thunnus thynnus) with motion-sensitive tags and video cameras to quantify the gaits and kinematics used by wild fish. Our data reveal significant variety in the locomotory kinematics of Atlantic bluefin tuna, ranging from continuous locomotion to two types of intermittent locomotion. The tuna sustained swimming speeds in excess of 1.5 m s-1 (0.6 body lengths s-1), while beating their tail at a frequency of approximately 1 Hz. While diving, some descents were entirely composed of passive glides, with slower descent rates featuring more gliding, while ascents were primarily composed of active swimming. The observed swimming behaviour of Atlantic bluefin tuna is consistent with theoretical models predicting such intermittent locomotion to result in mechanical and physiological advantages. Our results confirm that Atlantic bluefin tuna possess behavioural specializations to increase their locomotory performance, which together with their unique physiology improve their capacity to use pelagic and mesopelagic habitats.
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Affiliation(s)
- Adrian C. Gleiss
- Tuna Research and Conservation Centre, Hopkins Marine Station, Stanford University, 120 Oceanview Boulevard, 93950 Pacific Grove, USA
- Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
- College of Science, Health, Engineering and Education, Environment and Conservation Sciences, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia
| | - Robert J. Schallert
- Tuna Research and Conservation Centre, Hopkins Marine Station, Stanford University, 120 Oceanview Boulevard, 93950 Pacific Grove, USA
| | - Jonathan J. Dale
- Tuna Research and Conservation Centre, Hopkins Marine Station, Stanford University, 120 Oceanview Boulevard, 93950 Pacific Grove, USA
| | - Steve G. Wilson
- Tuna Research and Conservation Centre, Hopkins Marine Station, Stanford University, 120 Oceanview Boulevard, 93950 Pacific Grove, USA
| | - Barbara A. Block
- Tuna Research and Conservation Centre, Hopkins Marine Station, Stanford University, 120 Oceanview Boulevard, 93950 Pacific Grove, USA
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15
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Temperature dependent pre- and postprandial activity in Pacific bluefin tuna (Thunnus orientalis). Comp Biochem Physiol A Mol Integr Physiol 2019; 231:131-139. [DOI: 10.1016/j.cbpa.2019.01.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 01/29/2019] [Accepted: 01/29/2019] [Indexed: 11/24/2022]
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16
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Estimating Natural Mortality of Atlantic Bluefin Tuna Using Acoustic Telemetry. Sci Rep 2019; 9:4918. [PMID: 30894557 PMCID: PMC6426944 DOI: 10.1038/s41598-019-40065-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 02/04/2019] [Indexed: 11/08/2022] Open
Abstract
Atlantic bluefin tuna (Thunnus thynnus) are highly migratory fish with a contemporary range spanning the North Atlantic Ocean. Bluefin tuna populations have undergone severe decline and the status of the fish within each population remains uncertain. Improved biological knowledge, particularly of natural mortality and rates of mixing of the western (GOM) and eastern (Mediterranean) populations, is key to resolving the current status of the Atlantic bluefin tuna. We evaluated the potential for acoustic tags to yield empirical estimates of mortality and migration rates for long-lived, highly migratory species such as Atlantic bluefin tuna. Bluefin tuna tagged in the Gulf of St. Lawrence (GSL) foraging ground (2009-2016) exhibited high detection rates post release, with 91% crossing receiver lines one year post tagging, 61% detected after year two at large, with detections up to ~1700 days post deployment. Acoustic detections per individual fish ranged from 3 to 4759 receptions. A spatially-structured Bayesian mark recapture model was applied to the acoustic detection data for Atlantic bluefin tuna electronically tagged in the GSL to estimate the rate of instantaneous annual natural mortality. We report a median estimate of 0.10 yr-1 for this experiment. Our results demonstrate that acoustic tags can provide vital fisheries independent estimates for life history parameters critical for improving stock assessment models.
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17
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Morris JM, Gielazyn M, Krasnec MO, Takeshita R, Forth HP, Labenia JS, Linbo TL, French BL, Gill JA, Baldwin DH, Scholz NL, Incardona JP. Crude oil cardiotoxicity to red drum embryos is independent of oil dispersion energy. CHEMOSPHERE 2018; 213:205-214. [PMID: 30223125 DOI: 10.1016/j.chemosphere.2018.09.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 09/01/2018] [Accepted: 09/03/2018] [Indexed: 06/08/2023]
Abstract
The potential bioavailability of toxic chemicals from oil spills to water column organisms such as fish embryos may be influenced by physical dispersion along an energy gradient. For example, a surface slick with minimal wave action (low energy) could potentially produce different toxic effects from high energy situations such as pressurized discharge from a blown wellhead. Here we directly compared the toxicity of water accommodated fractions (WAFs) of oil prepared with low and high mixing energy (LEWAFs and HEWAFs, respectively) using surface oil samples collected during the 2010 Deepwater Horizon spill, and embryos of a representative nearshore species, red drum (Sciaenops ocellatus). Biological effects of each WAF type was quantified with several functional and morphological indices of developmental cardiotoxicity, providing additional insight into species-specific responses to oil exposure. Although the two WAF preparations yielded different profiles of polycyclic aromatic hydrocarbons (PAHs), cardiotoxic phenotypes were essentially identical. Based on benchmark thresholds for both morphological and functional cardiotoxicity, in general LEWAFs had lower thresholds for these phenotypes than HEWAFs based on total PAH measures. However, HEWAF and LEWAF toxicity thresholds were more similar when calculated based on estimates of dissolved PAHs only. Differences in thresholds were attributable to the weathering state of the oil samples.
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Affiliation(s)
- Jeffrey M Morris
- Abt Associates, 1881 Ninth St., Suite 201, Boulder, CO, 80302, USA
| | - Michel Gielazyn
- Assessment and Restoration Division, National Oceanic and Atmospheric Administration, 263 13th Ave. South, St. Petersburg, FL, 33701, USA
| | | | - Ryan Takeshita
- Abt Associates, 1881 Ninth St., Suite 201, Boulder, CO, 80302, USA
| | - Heather P Forth
- Abt Associates, 1881 Ninth St., Suite 201, Boulder, CO, 80302, USA
| | - Jana S Labenia
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA
| | - Tiffany L Linbo
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA
| | - Barbara L French
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA
| | - J Anthony Gill
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA
| | - David H Baldwin
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA
| | - Nathaniel L Scholz
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA
| | - John P Incardona
- Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 2725 Montlake Blvd. E., Seattle, WA, 98112, USA.
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18
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Crespo GO, Dunn DC, Reygondeau G, Boerder K, Worm B, Cheung W, Tittensor DP, Halpin PN. The environmental niche of the global high seas pelagic longline fleet. SCIENCE ADVANCES 2018; 4:eaat3681. [PMID: 30101192 PMCID: PMC6082651 DOI: 10.1126/sciadv.aat3681] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/14/2018] [Indexed: 05/09/2023]
Abstract
International interest in the protection and sustainable use of high seas biodiversity has grown in recent years. There is an opportunity for new technologies to enable improvements in management of these areas beyond national jurisdiction. We explore the spatial ecology and drivers of the global distribution of the high seas longline fishing fleet by creating predictive models of the distribution of fishing effort from newly available automatic identification system (AIS) data. Our results show how longline fishing effort can be predicted using environmental variables, many related to the expected distribution of the species targeted by longliners. We also find that the longline fleet has seasonal environmental preferences (for example, increased importance of cooler surface waters during boreal summer) and may only be using 38 to 64% of the available environmentally suitable fishing habitat. Possible explanations include misclassification of fishing effort, incomplete AIS coverage, or how potential range contractions of pelagic species may have reduced the abundance of fishing habitats in the open ocean.
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Affiliation(s)
- Guillermo Ortuño Crespo
- Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
- Corresponding author.
| | - Daniel C. Dunn
- Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
| | - Gabriel Reygondeau
- Nippon Foundation Nereus Program and Changing Ocean Research Unit, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Kristina Boerder
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4J1, Canada
| | - Boris Worm
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4J1, Canada
| | - William Cheung
- Nippon Foundation Nereus Program and Changing Ocean Research Unit, Institute for the Oceans and Fisheries, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Derek P. Tittensor
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4J1, Canada
- United Nations Environment Programme World Conservation Monitoring Centre, 219 Huntingdon Road, Cambridge CB3 0DL, UK
| | - Patrick N. Halpin
- Marine Geospatial Ecology Lab, Nicholas School of the Environment, Duke University, Durham, NC 27708, USA
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19
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Bishop A, Brown C, Rehberg M, Torres L, Horning M. Juvenile Steller sea lion ( Eumetopias jubatus) utilization distributions in the Gulf of Alaska. MOVEMENT ECOLOGY 2018; 6:6. [PMID: 29785269 PMCID: PMC5952600 DOI: 10.1186/s40462-018-0124-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND A utilization distribution quantifies the temporal and spatial probability of space use for individuals or populations. These patterns in movement arise from individuals' internal state and from their response to the external environment, and thus can provide insights for assessing factors associated with the management of threatened populations. The Western Distinct Population Segment of the Steller sea lion (Eumetopias jubatus) has declined to approximately 20% of levels encountered 40 years ago. At the height of the decline, juvenile survival appeared to be depressed and currently there is evidence that juvenile mortality due to predation may be constraining recovery in some regions. Therefore, our objectives were to identify what spaces are biologically important to juvenile Steller sea lions in the Kenai Fjords and Prince William Sound regions of the Gulf of Alaska. METHODS We examined geospatial location data from juvenile sea lions tagged between 2000 and 2014 (n = 84) and derived individual and pooled-population utilization distributions (UDs) from their movements. Core areas were defined from the UDs using an individual-based approach; this quantitatively confirmed that all individuals in our sample exhibited concentrated use within their home range (95% UD). Finally, we explored if variation in UD characteristics were associated with sex, season, age, or region. RESULTS We found evidence that individual juvenile home ranges were region and sex-specific, with males having larger home ranges on average. Core space characteristics were also sex-specific, and exhibited seasonal patterns of reduced size, increased proximity to haulouts, and increased intensity of use in the summer, but only in the Kenai Fjords-Gulf of Alaska region. CONCLUSIONS This study highlights the areas of biological importance during this vulnerable life history stage, and the demographic, seasonal, and spatial factors associated with variation in movement patterns for a marine mesopredator. This can be useful information for promoting species recovery, and for future efforts to understand ecological patterns such as predator-prey interactions.
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Affiliation(s)
- Amanda Bishop
- Alaska SeaLife Center, 301 Railway Avenue, Seward, AK 99664 USA
| | - Casey Brown
- Alaska SeaLife Center, 301 Railway Avenue, Seward, AK 99664 USA
| | - Michael Rehberg
- Alaska Department of Fish and Game, 333 Raspberry Road, Anchorage, AK 99518 USA
| | - Leigh Torres
- Marine Mammal Institute, Department of Fisheries and Wildlife, Oregon State University, 2030 SE Marine Science Dr, Newport, OR 97365 USA
| | - Markus Horning
- Alaska SeaLife Center, 301 Railway Avenue, Seward, AK 99664 USA
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20
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O'Neill R, Ó Maoiléidigh N, McGinnity P, Bond N, Culloty S. The novel use of pop-off satellite tags (PSATs) to investigate the migratory behaviour of European sea bass Dicentrarchus labrax. JOURNAL OF FISH BIOLOGY 2018; 92:1404-1421. [PMID: 29607514 DOI: 10.1111/jfb.13594] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 02/14/2018] [Indexed: 06/08/2023]
Abstract
A total of 12 adult European sea bass Dicentrarchus labrax were tagged with pop-off satellite archival tags (PSAT) in Irish coastal waters and in offshore waters in the north-east Celtic Sea between 2015 and 2016. Archived data were successfully recovered from five of the 12 tags deployed, three from fish released in inshore Irish waters and two from fish released offshore in the eastern Celtic Sea. All three fish tagged in inshore waters were found to undertake migrations into the open ocean coinciding with the spawning period. These fish also exhibited fidelity to inshore sites post-migration, returning to the same general location (within c. 73 km, which is roughly the predicted mean accuracy of the method) of their original release site. Although the number of tracks obtained here was limited, some degree of aggregation between inshore and offshore tagged fish in the eastern Celtic Sea was noted during the expected spawning period suggesting PSATs can provide new information on specific spawning locations of European sea bass.
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Affiliation(s)
- R O'Neill
- School of Biological, Earth and Environmental Sciences, University College Cork, Ireland
| | | | - P McGinnity
- School of Biological, Earth and Environmental Sciences, University College Cork, Ireland
| | - N Bond
- Marine Institute, Furnace, Newport, Co. Mayo, Ireland
| | - S Culloty
- School of Biological, Earth and Environmental Sciences, University College Cork, Ireland
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21
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Daly R, Smale MJ, Singh S, Anders D, Shivji M, K. Daly CA, Lea JSE, Sousa LL, Wetherbee BM, Fitzpatrick R, Clarke CR, Sheaves M, Barnett A. Refuges and risks: Evaluating the benefits of an expanded MPA network for mobile apex predators. DIVERS DISTRIB 2018. [DOI: 10.1111/ddi.12758] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
- Ryan Daly
- Save Our Seas Foundation - D'Arros Research Centre (SOSF-DRC); Genève Switzerland
- Port Elizabeth Museum at Bayworld; Port Elizabeth South Africa
| | - Malcolm J. Smale
- Port Elizabeth Museum at Bayworld; Port Elizabeth South Africa
- Department of Zoology and Institute for Coastal and Marine Research; Nelson Mandela Metropolitan University; Port Elizabeth South Africa
| | - Sarika Singh
- Department of Environmental Affairs; Government of South Africa; Cape Town South Africa
| | - Darrell Anders
- Department of Environmental Affairs; Government of South Africa; Cape Town South Africa
| | - Mahmood Shivji
- Department of Biological Sciences; The Guy Harvey Research Institute; Nova Southeastern University; Dania Beach FL USA
| | - Clare A. K. Daly
- Save Our Seas Foundation - D'Arros Research Centre (SOSF-DRC); Genève Switzerland
| | | | - Lara L. Sousa
- Wildlife Conservation Research Unit; Department of Zoology; University of Oxford; Recanati-Kaplan Centre; Tubney UK
| | - Bradley M. Wetherbee
- Department of Biological Sciences; The Guy Harvey Research Institute; Nova Southeastern University; Dania Beach FL USA
- Department of Biological Sciences; University of Rhode Island; Kingston RI USA
| | - Richard Fitzpatrick
- College of Science & Engineering; James Cook University; Cairns QLD Australia
| | | | - Marcus Sheaves
- College of Science & Engineering; James Cook University; Cairns QLD Australia
| | - Adam Barnett
- College of Science & Engineering; James Cook University; Cairns QLD Australia
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22
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Mislan KAS, Deutsch CA, Brill RW, Dunne JP, Sarmiento JL. Projections of climate-driven changes in tuna vertical habitat based on species-specific differences in blood oxygen affinity. GLOBAL CHANGE BIOLOGY 2017; 23:4019-4028. [PMID: 28657206 DOI: 10.1111/gcb.13799] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 05/19/2017] [Indexed: 06/07/2023]
Abstract
Oxygen concentrations are hypothesized to decrease in many areas of the ocean as a result of anthropogenically driven climate change, resulting in habitat compression for pelagic animals. The oxygen partial pressure, pO2 , at which blood is 50% saturated (P50 ) is a measure of blood oxygen affinity and a gauge of the tolerance of animals for low ambient oxygen. Tuna species display a wide range of blood oxygen affinities (i.e., P50 values) and therefore may be differentially impacted by habitat compression as they make extensive vertical movements to forage on subdaily time scales. To project the effects of end-of-the-century climate change on tuna habitat, we calculate tuna P50 depths (i.e., the vertical position in the water column at which ambient pO2 is equal to species-specific blood P50 values) from 21st century Earth System Model (ESM) projections included in the fifth phase of the Climate Model Intercomparison Project (CMIP5). Overall, we project P50 depths to shoal, indicating likely habitat compression for tuna species due to climate change. Tunas that will be most impacted by shoaling are Pacific and southern bluefin tunas-habitat compression is projected for the entire geographic range of Pacific bluefin tuna and for the spawning region of southern bluefin tuna. Vertical shifts in P50 depths will potentially influence resource partitioning among Pacific bluefin, bigeye, yellowfin, and skipjack tunas in the northern subtropical and eastern tropical Pacific Ocean, the Arabian Sea, and the Bay of Bengal. By establishing linkages between tuna physiology and environmental conditions, we provide a mechanistic basis to project the effects of anthropogenic climate change on tuna habitats.
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Affiliation(s)
- K A S Mislan
- School of Oceanography, University of Washington, Seattle, WA, USA
- eScience Institute, University of Washington, Seattle, WA, USA
| | - Curtis A Deutsch
- School of Oceanography, University of Washington, Seattle, WA, USA
| | - Richard W Brill
- Department of Fisheries Science, Virginia Institute of Marine Science, College of William & Mary, Gloucester Point, VA, USA
- Behavioral Ecology Branch, James J. Howard Marine Sciences Laboratory, NOAA Northeast Fisheries Science Center, Highlands, NJ, USA
| | - John P Dunne
- NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ, USA
| | - Jorge L Sarmiento
- Atmospheric and Oceanic Sciences Program, Princeton University, Princeton, NJ, USA
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Mannocci L, Boustany AM, Roberts JJ, Palacios DM, Dunn DC, Halpin PN, Viehman S, Moxley J, Cleary J, Bailey H, Bograd SJ, Becker EA, Gardner B, Hartog JR, Hazen EL, Ferguson MC, Forney KA, Kinlan BP, Oliver MJ, Perretti CT, Ridoux V, Teo SLH, Winship AJ. Temporal resolutions in species distribution models of highly mobile marine animals: Recommendations for ecologists and managers. DIVERS DISTRIB 2017. [DOI: 10.1111/ddi.12609] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Affiliation(s)
- Laura Mannocci
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Andre M. Boustany
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Jason J. Roberts
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Daniel M. Palacios
- Marine Mammal Institute and Department of Fisheries and Wildlife; Oregon State University; Hatfield Marine Science Center; Newport OR USA
| | - Daniel C. Dunn
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Patrick N. Halpin
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Shay Viehman
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Jerry Moxley
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Jesse Cleary
- Marine Geospatial Ecology Lab; Nicholas School of the Environment; Duke University; Durham NC USA
| | - Helen Bailey
- Chesapeake Biological Laboratory; University of Maryland Center for Environmental Science; Solomons MD USA
| | - Steven J. Bograd
- Environmental Research Division; National Oceanic and Atmospheric Administration; Southwest Fisheries Science Center; Monterey CA USA
| | - Elizabeth A. Becker
- Protected Resources Division; National Oceanic and Atmospheric Administration; Southwest Fisheries Science Center; Santa Cruz CA USA
- ManTech International Corporation; Solana Beach CA USA
| | - Beth Gardner
- School of Environmental and Forest Sciences; University of Washington; Seattle WA USA
| | | | - Elliott L. Hazen
- Environmental Research Division; National Oceanic and Atmospheric Administration; Southwest Fisheries Science Center; Monterey CA USA
| | - Megan C. Ferguson
- Marine Mammal Laboratory; National Oceanic and Atmospheric Administration Fisheries; Alaska Fisheries Science Center; Seattle WA USA
| | - Karin A. Forney
- Protected Resources Division; National Oceanic and Atmospheric Administration; Southwest Fisheries Science Center; Santa Cruz CA USA
| | - Brian P. Kinlan
- National Oceanic and Atmospheric Administration; National Ocean Service; National Centers for Coastal Ocean Science; Center for Coastal Monitoring and Assessment; Biogeography Branch; Silver Spring MD USA
| | - Matthew J. Oliver
- College of Earth, Ocean and Environment; University of Delaware; Lewes DE USA
| | - Charles T. Perretti
- National Oceanic and Atmospheric Administration; National Marine Fisheries Service; Northeast Fisheries Science Center; Woods Hole MA USA
| | - Vincent Ridoux
- Centre d'Etudes Biologiques de Chizé; UMR 7372 Université de La Rochelle-CNRS; La Rochelle France
| | - Steven L. H. Teo
- National Oceanic and Atmospheric Administration; National Marine Fisheries Service; Southwest Fisheries Science Center; La Jolla CA USA
| | - Arliss J. Winship
- National Oceanic and Atmospheric Administration; National Ocean Service; National Centers for Coastal Ocean Science; Center for Coastal Monitoring and Assessment; Biogeography Branch; Silver Spring MD USA
- CSS-Dynamac; Fairfax VA USA
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24
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Díez G, Moreno G, Galaz T, Dagorn L, Murua J. Digestive activity and stomach temperature in farmed bluefin tuna Thunnus thynnus measured by acoustic tag. JOURNAL OF FISH BIOLOGY 2017; 90:2504-2511. [PMID: 28474410 DOI: 10.1111/jfb.13328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 04/03/2017] [Indexed: 06/07/2023]
Abstract
Eight farmed Atlantic bluefin tuna Thunnus thynnus were tagged with temperature and depth transmitters inserted in chub mackerels Scomber colias to characterize their digestive activity, feeding physiology and behaviour in captivity. Results obtained in the experiment can be used to optimize daily T. thynnus feeding strategy in farms, reducing the early regurgitation of food and thus the environmental effects of inappropriate feeding practices.
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Affiliation(s)
- G Díez
- AZTI, Marine Research Division, Txatxarramendi z/g (48395), Sukarrieta, Bizkaia, Spain
| | - G Moreno
- International Seafood Sustainability Foundation (ISSF), 601 New Jersey Ave NW Suite 220, Washington, DC, 20001, U.S.A
| | - T Galaz
- Mediterranean Aquafarm Services S.L., Rio Bidasoa n° 6A. 30370 Playa Honda, Cartagena, Murcia, Spain
| | - L Dagorn
- Institut de Recherche pour le Développement (IRD), UMR MARBEC (IRD, IFREMER, Univ. Montpellier, CNRS), Avenue J. Monnet, 34203, Sète Cedex, France
| | - J Murua
- AZTI, Marine Research Division, Txatxarramendi z/g (48395), Sukarrieta, Bizkaia, Spain
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25
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Olson RJ, Young JW, Ménard F, Potier M, Allain V, Goñi N, Logan JM, Galván-Magaña F. Bioenergetics, Trophic Ecology, and Niche Separation of Tunas. ADVANCES IN MARINE BIOLOGY 2016; 74:199-344. [PMID: 27573052 DOI: 10.1016/bs.amb.2016.06.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
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.
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Affiliation(s)
- R J Olson
- Inter-American Tropical Tuna Commission, La Jolla, CA, United States.
| | - J W Young
- CSIRO Marine and Atmospheric Research, Hobart, TAS, Australia
| | - F Ménard
- Institut de Recherche pour le Développement (IRD), Mediterranean Institute of Oceanography (Aix-Marseille Université, CNRS, IRD, Université de Toulon), Marseille, France
| | - M Potier
- IRD, UMR MARBEC (IRD, UM, Ifremer, CNRS), Sète cedex, France
| | - V Allain
- Pacific Community (SPC), Nouméa cedex, New Caledonia
| | - N Goñi
- AZTI-Tecnalia/Marine Research, Pasaia, Gipuzkoa, Spain
| | - J M Logan
- Massachusetts Division of Marine Fisheries, New Bedford, MA, United States
| | - F Galván-Magaña
- Instituto Politécnico Nacional, Centro Interdisciplinario de Ciencias Marinas, La Paz, Baja California Sur, Mexico
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26
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Scale-dependent to scale-free: daily behavioural switching and optimized searching in a marine predator. Anim Behav 2016. [DOI: 10.1016/j.anbehav.2015.12.029] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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27
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Shiels HA, Galli GLJ, Block BA. Cardiac function in an endothermic fish: cellular mechanisms for overcoming acute thermal challenges during diving. Proc Biol Sci 2016; 282:20141989. [PMID: 25540278 DOI: 10.1098/rspb.2014.1989] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Understanding the physiology of vertebrate thermal tolerance is critical for predicting how animals respond to climate change. Pacific bluefin tuna experience a wide range of ambient sea temperatures and occupy the largest geographical niche of all tunas. Their capacity to endure thermal challenge is due in part to enhanced expression and activity of key proteins involved in cardiac excitation-contraction coupling, which improve cardiomyocyte function and whole animal performance during temperature change. To define the cellular mechanisms that enable bluefin tuna hearts to function during acute temperature change, we investigated the performance of freshly isolated ventricular myocytes using confocal microscopy and electrophysiology. We demonstrate that acute cooling and warming (between 8 and 28°C) modulates the excitability of the cardiomyocyte by altering the action potential (AP) duration and the amplitude and kinetics of the cellular Ca(2+) transient. We then explored the interactions between temperature, adrenergic stimulation and contraction frequency, and show that when these stressors are combined in a physiologically relevant way, they alter AP characteristics to stabilize excitation-contraction coupling across an acute 20°C temperature range. This allows the tuna heart to maintain consistent contraction and relaxation cycles during acute thermal challenges. We hypothesize that this cardiac capacity plays a key role in the bluefin tunas' niche expansion across a broad thermal and geographical range.
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Affiliation(s)
- H A Shiels
- Faculty of Life Sciences, The University of Manchester, Core Technology Facility, Grafton Street, Manchester M13 9PL, UK
| | - G L J Galli
- Faculty of Medical and Human Sciences, The University of Manchester, Core Technology Facility, Grafton Street, Manchester M13 9PL, UK
| | - B A Block
- Department of Biology, Tuna Research and Conservation Center, Stanford University, 120 Oceanview Boulevard, Pacific Grove, CA 93950, USA
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28
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Ocean-wide tracking of pelagic sharks reveals extent of overlap with longline fishing hotspots. Proc Natl Acad Sci U S A 2016; 113:1582-7. [PMID: 26811467 DOI: 10.1073/pnas.1510090113] [Citation(s) in RCA: 69] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Overfishing is arguably the greatest ecological threat facing the oceans, yet catches of many highly migratory fishes including oceanic sharks remain largely unregulated with poor monitoring and data reporting. Oceanic shark conservation is hampered by basic knowledge gaps about where sharks aggregate across population ranges and precisely where they overlap with fishers. Using satellite tracking data from six shark species across the North Atlantic, we show that pelagic sharks occupy predictable habitat hotspots of high space use. Movement modeling showed sharks preferred habitats characterized by strong sea surface-temperature gradients (fronts) over other available habitats. However, simultaneous Global Positioning System (GPS) tracking of the entire Spanish and Portuguese longline-vessel fishing fleets show an 80% overlap of fished areas with hotspots, potentially increasing shark susceptibility to fishing exploitation. Regions of high overlap between oceanic tagged sharks and longliners included the North Atlantic Current/Labrador Current convergence zone and the Mid-Atlantic Ridge southwest of the Azores. In these main regions, and subareas within them, shark/vessel co-occurrence was spatially and temporally persistent between years, highlighting how broadly the fishing exploitation efficiently "tracks" oceanic sharks within their space-use hotspots year-round. Given this intense focus of longliners on shark hotspots, our study argues the need for international catch limits for pelagic sharks and identifies a future role of combining fine-scale fish and vessel telemetry to inform the ocean-scale management of fisheries.
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Mariani P, Křivan V, MacKenzie BR, Mullon C. The migration game in habitat network: the case of tuna. THEOR ECOL-NETH 2015. [DOI: 10.1007/s12080-015-0290-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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30
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Trumbić Ž, Bekaert M, Taggart JB, Bron JE, Gharbi K, Mladineo I. Development and validation of a mixed-tissue oligonucleotide DNA microarray for Atlantic bluefin tuna, Thunnus thynnus (Linnaeus, 1758). BMC Genomics 2015; 16:1007. [PMID: 26607231 PMCID: PMC4659210 DOI: 10.1186/s12864-015-2208-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 11/12/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The largest of the tuna species, Atlantic bluefin tuna (Thunnus thynnus), inhabits the North Atlantic Ocean and the Mediterranean Sea and is considered to be an endangered species, largely a consequence of overfishing. T. thynnus aquaculture, referred to as fattening or farming, is a capture based activity dependent on yearly renewal from the wild. Thus, the development of aquaculture practices independent of wild resources can provide an important contribution towards ensuring security and sustainability of this species in the longer-term. The development of such practices is today greatly assisted by large scale transcriptomic studies. RESULTS We have used pyrosequencing technology to sequence a mixed-tissue normalised cDNA library, derived from adult T. thynnus. A total of 976,904 raw sequence reads were assembled into 33,105 unique transcripts having a mean length of 893 bases and an N50 of 870. Of these, 33.4% showed similarity to known proteins or gene transcripts and 86.6% of them were matched to the congeneric Pacific bluefin tuna (Thunnus orientalis) genome, compared to 70.3% for the more distantly related Nile tilapia (Oreochromis niloticus) genome. Transcript sequences were used to develop a novel 15 K Agilent oligonucleotide DNA microarray for T. thynnus and comparative tissue gene expression profiles were inferred for gill, heart, liver, ovaries and testes. Functional contrasts were strongest between gills and ovaries. Gills were particularly associated with immune system, signal transduction and cell communication, while ovaries displayed signatures of glycan biosynthesis, nucleotide metabolism, transcription, translation, replication and repair. CONCLUSIONS Sequence data generated from a novel mixed-tissue T. thynnus cDNA library provide an important transcriptomic resource that can be further employed for study of various aspects of T. thynnus ecology and genomics, with strong applications in aquaculture. Tissue-specific gene expression profiles inferred through the use of novel oligo-microarray can serve in the design of new and more focused transcriptomic studies for future research of tuna physiology and assessment of the welfare in a production environment.
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Affiliation(s)
- Željka Trumbić
- University Department of Marine Studies, University of Split, Split, Croatia.
| | - Michaël Bekaert
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, Scotland, UK.
| | - John B Taggart
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, Scotland, UK.
| | - James E Bron
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, Scotland, UK.
| | - Karim Gharbi
- Edinburgh Genomics, School of Biological Sciences, University of Edinburgh, Edinburgh, EH9 3FL, Scotland, UK.
| | - Ivona Mladineo
- Institute of Oceanography and Fisheries, Split, Croatia.
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Hsu AC, Boustany AM, Roberts JJ, Chang JH, Halpin PN. Tuna and swordfish catch in the U.S. northwest Atlantic longline fishery in relation to mesoscale eddies. FISHERIES OCEANOGRAPHY 2015; 24:508-520. [PMID: 27667909 PMCID: PMC5020580 DOI: 10.1111/fog.12125] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 08/06/2015] [Indexed: 06/06/2023]
Abstract
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.
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Affiliation(s)
- Ango C Hsu
- Marine Geospatial Ecology Lab Nicholas School of the Environment Duke University Marine Lab A328LSRC Building Durham NC 27708-0328 U.S.A.; School of Marine Sciences University of Maine 5706 Aubert Hall Orono ME 04469-5706 U.S.A
| | - Andre M Boustany
- Marine Geospatial Ecology Lab Nicholas School of the Environment Duke University Marine Lab A328 LSRC Building Durham NC 27708-0328 U.S.A
| | - Jason J Roberts
- Marine Geospatial Ecology Lab Nicholas School of the Environment Duke University Marine Lab A328 LSRC Building Durham NC 27708-0328 U.S.A
| | - Jui-Han Chang
- School of Marine Sciences University of Maine 5706 Aubert Hall Orono ME 04469-5706 U.S.A
| | - Patrick N Halpin
- Marine Geospatial Ecology Lab Nicholas School of the Environment Duke University Marine Lab A328 LSRC Building Durham NC 27708-0328 U.S.A
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Bauer RK, Fromentin JM, Demarcq H, Brisset B, Bonhommeau S. Co-Occurrence and Habitat Use of Fin Whales, Striped Dolphins and Atlantic Bluefin Tuna in the Northwestern Mediterranean Sea. PLoS One 2015; 10:e0139218. [PMID: 26458254 PMCID: PMC4601798 DOI: 10.1371/journal.pone.0139218] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Accepted: 09/10/2015] [Indexed: 11/28/2022] Open
Abstract
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).
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Affiliation(s)
- Robert Klaus Bauer
- IFREMER (Institut Français de Recherche pour l’Exploitation de la MER), Resarch Unit Marbec (Marine Biodiversity, Exploitation and Conservation), Sète, France
| | - Jean-Marc Fromentin
- IFREMER (Institut Français de Recherche pour l’Exploitation de la MER), Resarch Unit Marbec (Marine Biodiversity, Exploitation and Conservation), Sète, France
- * E-mail:
| | - Hervé Demarcq
- IRD (Institut de Recherche pour le Développement), Resarch Unit Marbec (Marine Biodiversity, Exploitation and Conservation), Sète, France
| | - Blandine Brisset
- IFREMER (Institut Français de Recherche pour l’Exploitation de la MER), Resarch Unit Marbec (Marine Biodiversity, Exploitation and Conservation), Sète, France
| | - Sylvain Bonhommeau
- IFREMER (Institut Français de Recherche pour l’Exploitation de la MER), Resarch Unit Marbec (Marine Biodiversity, Exploitation and Conservation), Sète, France
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Bouchet PJ, Meeuwig JJ. Drifting baited stereo-videography: a novel sampling tool for surveying pelagic wildlife in offshore marine reserves. Ecosphere 2015. [DOI: 10.1890/es14-00380.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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McFarlane Tranquilla L, Montevecchi W, Hedd A, Regular P, Robertson G, Fifield D, Devillers R. Ecological segregation among Thick-billed Murres (Uria lomvia) and Common Murres (Uria aalge) in the Northwest Atlantic persists through the nonbreeding season. CAN J ZOOL 2015. [DOI: 10.1139/cjz-2014-0315] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To study the influence of inter- and intra-specific interactions on patterns of ecological segregation in nonbreeding habitat, we used geolocators to track year-round movements of congeneric and partially sympatric Thick-billed Murres (Uria lomvia (L., 1758)) and Common Murres (Uria aalge (Pontoppidan, 1763)) from seven Canadian colonies during 2007–2011. Locations from 142 individuals were (i) examined for species- and colony-specific spatiotemporal patterns, (ii) mapped with environmental data, and (iii) used to delineate core wintering areas. Compared with Common Murres, Thick-billed Murres dispersed across a wider range of latitudes and environments, had larger winter ranges, and showed greater variation in seasonal timing of movements. These interspecific differences were consistent at two scales: among colonies spanning a wide latitudinal range and at a sympatric colony. Intraspecifically, nonbreeding ecological segregation was more pronounced among colonies of Thick-billed Murres than of Common Murres: colonies of Thick-billed Murres tended to follow distinct movement patterns and segregate by latitude, whereas colonies of Common Murres segregated very little; moreover, the extent of segregation was more variable among Thick-billed Murres than Common Murres. For Thick-billed Murres, rather than complete divergence of winter ecological niche from Common Murres, we found a “widening” of an overlapping niche. This strategy of increased movement flexibility may enable Thick-billed Murres to mitigate competition both intra- and inter-specifically; we propose this movement strategy may have played a role in species divergence.
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Affiliation(s)
- L. McFarlane Tranquilla
- Cognitive and Behavioural Ecology, Department of Psychology, Memorial University of Newfoundland, St. John’s, NL A1B 3X9, Canada
| | - W.A. Montevecchi
- Cognitive and Behavioural Ecology, Department of Psychology, Memorial University of Newfoundland, St. John’s, NL A1B 3X9, Canada
| | - A. Hedd
- Cognitive and Behavioural Ecology, Department of Psychology, Memorial University of Newfoundland, St. John’s, NL A1B 3X9, Canada
| | - P.M. Regular
- Cognitive and Behavioural Ecology, Department of Psychology, Memorial University of Newfoundland, St. John’s, NL A1B 3X9, Canada
| | - G.J. Robertson
- Wildlife Research Division, Environment Canada, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada
| | - D.A. Fifield
- Wildlife Research Division, Environment Canada, 6 Bruce Street, Mount Pearl, NL A1N 4T3, Canada
| | - R. Devillers
- Department of Geography, Memorial University of Newfoundland, St. John’s, NL A1B 3X9, Canada
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Cermeño P, Quílez-Badia G, Ospina-Alvarez A, Sainz-Trápaga S, Boustany AM, Seitz AC, Tudela S, Block BA. Electronic tagging of Atlantic bluefin tuna (Thunnus thynnus, L.) reveals habitat use and behaviors in the Mediterranean Sea. PLoS One 2015; 10:e0116638. [PMID: 25671316 PMCID: PMC4324982 DOI: 10.1371/journal.pone.0116638] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2014] [Accepted: 12/11/2014] [Indexed: 12/03/2022] Open
Abstract
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.
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Affiliation(s)
- Pablo Cermeño
- Department of Biology, Stanford University, Hopkins Marine Station, Pacific Grove, California 93950, United States of America
- WWF Mediterranean Programme, Barcelona 08002, Spain
- * E-mail:
| | | | - Andrés Ospina-Alvarez
- WWF Mediterranean Programme, Barcelona 08002, Spain
- Center for Marine Conservation & Department of Ecology, Biological sciences Faculty, Pontificia Universidad Católica de Chile, Santiago de Chile 6513677, Chile
| | | | - Andre M. Boustany
- Department of Biology, Stanford University, Hopkins Marine Station, Pacific Grove, California 93950, United States of America
- Nicholas School of the Environment, Duke University, Durham, North Carolina 27708, United States of America
| | - Andy C. Seitz
- Tuna Research and Conservation Center, Monterey Bay Aquarium, Monterey, California 93940, United States of America
- School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, Alaska 99775, United States of America
| | - Sergi Tudela
- WWF Mediterranean Programme, Barcelona 08002, Spain
| | - Barbara A. Block
- Department of Biology, Stanford University, Hopkins Marine Station, Pacific Grove, California 93950, United States of America
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Vandeperre F, Aires-da-Silva A, Fontes J, Santos M, Serrão Santos R, Afonso P. Movements of blue sharks (Prionace glauca) across their life history. PLoS One 2014; 9:e103538. [PMID: 25119716 PMCID: PMC4131881 DOI: 10.1371/journal.pone.0103538] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 07/04/2014] [Indexed: 11/30/2022] Open
Abstract
Spatial structuring and segregation by sex and size is considered to be an intrinsic attribute of shark populations. These spatial patterns remain poorly understood, particularly for oceanic species such as blue shark (Prionace glauca), despite its importance for the management and conservation of this highly migratory species. This study presents the results of a long-term electronic tagging experiment to investigate the migratory patterns of blue shark, to elucidate how these patterns change across its life history and to assess the existence of a nursery area in the central North Atlantic. Blue sharks belonging to different life stages (n = 34) were tracked for periods up to 952 days during which they moved extensively (up to an estimated 28.139 km), occupying large parts of the oceanic basin. Notwithstanding a large individual variability, there were pronounced differences in movements and space use across the species' life history. The study provides strong evidence for the existence of a discrete central North Atlantic nursery, where juveniles can reside for up to at least 2 years. In contrast with previously described nurseries of coastal and semi-pelagic sharks, this oceanic nursery is comparatively vast and open suggesting that shelter from predators is not its main function. Subsequently, male and female blue sharks spatially segregate. Females engage in seasonal latitudinal migrations until approaching maturity, when they undergo an ontogenic habitat shift towards tropical latitudes. In contrast, juvenile males generally expanded their range southward and apparently displayed a higher degree of behavioural polymorphism. These results provide important insights into the spatial ecology of pelagic sharks, with implications for the sustainable management of this heavily exploited shark, especially in the central North Atlantic where the presence of a nursery and the seasonal overlap and alternation of different life stages coincides with a high fishing mortality.
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Affiliation(s)
- Frederic Vandeperre
- Centre of IMAR of the University of the Azores; Department of Oceanography and Fisheries, Horta, Portugal
- LARSyS Associated Laboratory, Lisboa, Portugal
- * E-mail:
| | | | - Jorge Fontes
- Centre of IMAR of the University of the Azores; Department of Oceanography and Fisheries, Horta, Portugal
- LARSyS Associated Laboratory, Lisboa, Portugal
| | - Marco Santos
- Centre of IMAR of the University of the Azores; Department of Oceanography and Fisheries, Horta, Portugal
- LARSyS Associated Laboratory, Lisboa, Portugal
| | - Ricardo Serrão Santos
- Centre of IMAR of the University of the Azores; Department of Oceanography and Fisheries, Horta, Portugal
- LARSyS Associated Laboratory, Lisboa, Portugal
| | - Pedro Afonso
- Centre of IMAR of the University of the Azores; Department of Oceanography and Fisheries, Horta, Portugal
- LARSyS Associated Laboratory, Lisboa, Portugal
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37
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Goyert HF, Manne LL, Veit RR. Facilitative interactions among the pelagic community of temperate migratory terns, tunas and dolphins. OIKOS 2014. [DOI: 10.1111/oik.00814] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Holly F. Goyert
- Dept of Biology, Subprogram in Ecology, Evolutionary Biology and Behavior; The Graduate Center, City Univ. of New York; 365 Fifth Avenue New York NY 10016
- College of Staten Island, CUNY; 6S-143, 2800 Victory Boulevard Staten Island NY 10314 USA
| | - Lisa L. Manne
- Dept of Biology, Subprogram in Ecology, Evolutionary Biology and Behavior; The Graduate Center, City Univ. of New York; 365 Fifth Avenue New York NY 10016
- College of Staten Island, CUNY; 6S-143, 2800 Victory Boulevard Staten Island NY 10314 USA
| | - Richard R. Veit
- Dept of Biology, Subprogram in Ecology, Evolutionary Biology and Behavior; The Graduate Center, City Univ. of New York; 365 Fifth Avenue New York NY 10016
- College of Staten Island, CUNY; 6S-143, 2800 Victory Boulevard Staten Island NY 10314 USA
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38
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Vaudo JJ, Wetherbee BM, Harvey G, Nemeth RS, Aming C, Burnie N, Howey-Jordan LA, Shivji MS. Intraspecific variation in vertical habitat use by tiger sharks (Galeocerdo cuvier) in the western North Atlantic. Ecol Evol 2014; 4:1768-86. [PMID: 24963376 PMCID: PMC4063475 DOI: 10.1002/ece3.1053] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Revised: 03/03/2014] [Accepted: 03/11/2014] [Indexed: 11/13/2022] Open
Abstract
Tiger sharks (Galeocerdo cuvier) are a wide ranging, potentially keystone predator species that display a variety of horizontal movement patterns, making use of coastal and pelagic waters. Far less, however, is known about their vertical movements and use of the water column. We used pop-up satellite archival tags with two data sampling rates (high rate and standard rate tags) to investigate the vertical habitat use and diving behavior of tiger sharks tagged on the Puerto Rico–Virgin Islands platform and off Bermuda between 2008 and 2009. Useable data were received from nine of 14 sharks tagged, tracked over a total of 529 days. Sharks spent the majority of their time making yo-yo dives within the upper 50 m of the water column and considerable time within the upper 5 m of the water column. As a result, sharks typically occupied a narrow daily temperature range (∼2°C). Dives to greater than 200 m were common, and all sharks made dives to at least 250 m, with one shark reaching a depth of 828 m. Despite some similarities among individuals, a great deal of intraspecific variability in vertical habit use was observed. Four distinct depth distributions that were not related to tagging location, horizontal movements, sex, or size were detected. In addition, similar depth distributions did not necessitate similar dive patterns among sharks. Recognition of intraspecific variability in habitat use of top predators can be crucial for effective management of these species and for understanding their influence on ecosystem dynamics.
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Affiliation(s)
- Jeremy J Vaudo
- The Guy Harvey Research Institute, Nova Southeastern University Oceanographic Center Dania Beach, Florida
| | - Bradley M Wetherbee
- The Guy Harvey Research Institute, Nova Southeastern University Oceanographic Center Dania Beach, Florida ; Department of Biological Sciences, University of Rhode Island Kingston, Rhode Island
| | - Guy Harvey
- The Guy Harvey Research Institute, Nova Southeastern University Oceanographic Center Dania Beach, Florida
| | - Richard S Nemeth
- Center for Marine and Environmental Studies, University of the Virgin Islands Charlotte Amalie, St. Thomas, US Virgin Islands
| | - Choy Aming
- The Bermuda Shark Project Flatts, Bermuda
| | | | | | - Mahmood S Shivji
- The Guy Harvey Research Institute, Nova Southeastern University Oceanographic Center Dania Beach, Florida
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Leatherback turtle movements, dive behavior, and habitat characteristics in ecoregions of the Northwest Atlantic Ocean. PLoS One 2014; 9:e91726. [PMID: 24646920 PMCID: PMC3960146 DOI: 10.1371/journal.pone.0091726] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2013] [Accepted: 02/14/2014] [Indexed: 12/05/2022] Open
Abstract
Leatherback sea turtles, Dermochelys coriacea, are highly migratory predators that feed exclusively on gelatinous zooplankton, thus playing a unique role in coastal and pelagic food webs. From 2007 to 2010, we used satellite telemetry to monitor the movements and dive behavior of nine adult and eleven subadult leatherbacks captured on the Northeast USA shelf and tracked throughout the Northwest Atlantic. Leatherback movements and environmental associations varied by oceanographic region, with slow, sinuous, area-restricted search behavior and shorter, shallower dives occurring in cool (median sea surface temperature: 18.4°C), productive (median chlorophyll a: 0.80 mg m−3), shallow (median bathymetry: 57 m) shelf habitat with strong sea surface temperature gradients (median SST gradient: 0.23°C km−1) at temperate latitudes. Leatherbacks were highly aggregated in temperate shelf and slope waters during summer, early fall, and late spring and more widely dispersed in subtropical and tropical oceanic and neritic habitat during late fall, winter and early spring. We investigated the relationship of ecoregion, satellite-derived surface chlorophyll, satellite-derived sea surface temperature, SST gradient, chlorophyll gradient and bathymetry with leatherback search behavior using generalized linear mixed-effects models. The most well supported model showed that differences in leatherback search behavior were best explained by ecoregion and regional differences in bathymetry and SST. Within the Northwest Atlantic Shelves region, leatherbacks increased path sinuosity (i.e., looping movements) with increasing SST, but this relationship reversed within the Gulf Stream region. Leatherbacks increased path sinuosity with decreasing water depth in temperate and tropical shelf habitats. This relationship is consistent with increasing epipelagic gelatinous zooplankton biomass with decreasing water depth, and bathymetry may be a key feature in identifying leatherback foraging habitat in neritic regions. High-use habitat for leatherbacks in our study occurred in coastal waters of the North American eastern seaboard and eastern Caribbean, putting turtles at heightened risk from land- and ocean-based human activity.
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40
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Gordoa A, Carreras G. Determination of temporal spawning patterns and hatching time in response to temperature of Atlantic bluefin tuna (Thunnus thynnus) in the Western Mediterranean. PLoS One 2014; 9:e90691. [PMID: 24608107 PMCID: PMC3946554 DOI: 10.1371/journal.pone.0090691] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 02/04/2014] [Indexed: 11/18/2022] Open
Abstract
This study analysed the temporal pattern of Atlantic bluefin tuna (ABFT) spawning in the Balearic spawning ground and examined its reproductive performance after years in captivity. Furthermore, ABFT hatching time at different on-site temperatures was determined for the first time. Spawning surveys were carried out in 4 spawning seasons (2009–2012) aboard tuna transport vessels. Three groups of spawners were monitored: a captive group transported to the spawning region and monitored throughout the four spawning seasons and two wild groups caught in 2009 and 2010 which were transferred to a monitoring transport cage immediately after being caught. Surface plankton samples were collected nightly, beginning immediately after the first purse seine catches were made and concluding after spawning was observed to have ended. All groups displayed the same spawning hours, restricted between 2:00–5:00 a.m. The captive group, as they got older, shifted towards the earliest hour, suggesting an age influence on reproductive time. The onset of spawning varied annually from the end of May to the beginning of June at temperatures around 19°C–20°C, ending by the second week of July. The peak of spawning was consistently around the summer solstice, June 15th–30th. The results showed the negative effect of unstable oceanographic conditions in the spawning process which might influence the annual reproductive success of ABFT. The influence of temperature on hatching time was higher than that observed in other tuna species, twice as fast at 26°C (23 h) as at 19.5°C (49 h). Overall, this study shows the strength of the internal mechanism in ABFT that controls spawning traits. Spawning in ABFT is cyclical and highly synchronised on diel and annual scales. We consider that the timing of spawning is rather influenced by day length and its adaptive significance is discussed.
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Affiliation(s)
- Ana Gordoa
- Department of Marine Ecology, Centro de Estudios Avanzados de Blanes, Spanish National Research Council (CSIC), Blanes, Gerona, Spain
- * E-mail:
| | - Gustavo Carreras
- Department of Marine Ecology, Centro de Estudios Avanzados de Blanes, Spanish National Research Council (CSIC), Blanes, Gerona, Spain
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41
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Whitlock RE, Walli A, Cermeño P, Rodriguez LE, Farwell C, Block BA. Quantifying energy intake in Pacific bluefin tuna (Thunnus orientalis) using the heat increment of feeding. J Exp Biol 2013; 216:4109-23. [DOI: 10.1242/jeb.084335] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Using implanted archival tags, we examined the effects of meal caloric value, food type (sardine or squid) and ambient temperature on the magnitude and duration of the heat increment of feeding in three captive juvenile Pacific bluefin tuna. The objective of our study was to develop a model that can be used to estimate energy intake in wild fish of similar body mass. Both the magnitude and duration of the heat increment of feeding (measured by visceral warming) showed a strong positive correlation with the caloric value of the ingested meal. Controlling for meal caloric value, the extent of visceral warming was significantly greater at lower ambient temperature. The extent of visceral warming was also significantly higher for squid meals compared with sardine meals. By using a hierarchical Bayesian model to analyze our data and treating individuals as random effects, we demonstrate how increases in visceral temperature can be used to estimate the energy intake of wild Pacific bluefin tuna of similar body mass to the individuals used in our study.
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Affiliation(s)
- R. E. Whitlock
- Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA
- Finnish Game and Fisheries Research Institute, Itäinen Pitkäkatu 3, FI-20520, Turku, Finland
| | - A. Walli
- Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA
| | - P. Cermeño
- Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA
- WWF Mediterranean Programme Office, C/Canuda 37, 08002 Barcelona, Spain
| | - L. E. Rodriguez
- Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA
| | - C. Farwell
- Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA
- Monterey Bay Aquarium, 886 Cannery Row, Monterey Bay, CA 93940, USA
| | - B. A. Block
- Tuna Research and Conservation Center, Stanford University, Hopkins Marine Station, Oceanview Boulevard, Pacific Grove, CA 93950, USA
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42
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Aranda G, Abascal FJ, Varela JL, Medina A. Spawning behaviour and post-spawning migration patterns of atlantic bluefin tuna (Thunnus thynnus) ascertained from satellite archival tags. PLoS One 2013; 8:e76445. [PMID: 24098502 PMCID: PMC3788109 DOI: 10.1371/journal.pone.0076445] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 08/20/2013] [Indexed: 11/18/2022] Open
Abstract
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.
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Affiliation(s)
- Guillermo Aranda
- Departmento de Biología, Facultad de Ciencias del Mar y Ambientales, Campus de Excelencia Internacional del Mar (CEI·MAR), Universidad de Cádiz, Puerto Real, Cádiz, Spain
| | - Francisco Javier Abascal
- Centro Oceanográfico de Canarias, Instituto Español de Oceanografía, Santa Cruz de Tenerife, Spain
| | - José Luis Varela
- Departmento de Biología, Facultad de Ciencias del Mar y Ambientales, Campus de Excelencia Internacional del Mar (CEI·MAR), Universidad de Cádiz, Puerto Real, Cádiz, Spain
| | - Antonio Medina
- Departmento de Biología, Facultad de Ciencias del Mar y Ambientales, Campus de Excelencia Internacional del Mar (CEI·MAR), Universidad de Cádiz, Puerto Real, Cádiz, Spain
- * E-mail:
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43
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Albaina A, Iriondo M, Velado I, Laconcha U, Zarraonaindia I, Arrizabalaga H, Pardo MA, Lutcavage M, Grant WS, Estonba A. Single nucleotide polymorphism discovery in albacore and Atlantic bluefin tuna provides insights into worldwide population structure. Anim Genet 2013; 44:678-92. [PMID: 23668670 DOI: 10.1111/age.12051] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2013] [Indexed: 10/26/2022]
Abstract
The optimal management of the commercially important, but mostly over-exploited, pelagic tunas, albacore (Thunnus alalunga Bonn., 1788) and Atlantic bluefin tuna (BFT; Thunnus thynnus L., 1758), requires a better understanding of population structure than has been provided by previous molecular methods. Despite numerous studies of both species, their population structures remain controversial. This study reports the development of single nucleotide polymorphisms (SNPs) in albacore and BFT and the application of these SNPs to survey genetic variability across the geographic ranges of these tunas. A total of 616 SNPs were discovered in 35 albacore tuna by comparing sequences of 54 nuclear DNA fragments. A panel of 53 SNPs yielded FST values ranging from 0.0 to 0.050 between samples after genotyping 460 albacore collected throughout the distribution of this species. No significant heterogeneity was detected within oceans, but between-ocean comparisons (Atlantic, Pacific and Indian oceans along with Mediterranean Sea) were significant. Additionally, a 17-SNP panel was developed in Atlantic BFT by cross-species amplification in 107 fish. This limited number of SNPs discriminated between samples from the two major spawning areas of Atlantic BFT (FST = 0.116). The SNP markers developed in this study can be used to genotype large numbers of fish without the need for standardizing alleles among laboratories.
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Affiliation(s)
- A Albaina
- Genetika, Antropologia Fisikoa eta Animalien Fisiologia Saila, Zientzia eta Teknologia Fakultatea, Euskal Herriko Unibertsitatea (UPV/EHU), P.O. Box 48940, Leioa, Spain
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Cort JL, Deguara S, Galaz T, Mèlich B, Artetxe I, Arregi I, Neilson J, Andrushchenko I, Hanke A, Neves dos Santos M, Estruch V, Lutcavage M, Knapp J, Compeán-Jiménez G, Solana-Sansores R, Belmonte A, Martínez D, Piccinetti C, Kimoto A, Addis P, Velasco M, De la Serna JM, Godoy D, Ceyhan T, Oray I, Karakulak S, Nøttestad L, López A, Ribalta O, Abid N, Idrissi M. Determination ofLmaxfor Atlantic Bluefin Tuna,Thunnus thynnus(L.), from Meta-Analysis of Published and Available Biometric Data. ACTA ACUST UNITED AC 2013. [DOI: 10.1080/10641262.2013.793284] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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45
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Clark TD, Farwell CJ, Rodriguez LE, Brandt WT, Block BA. Heart rate responses to temperature in free-swimming Pacific bluefin tuna (Thunnus orientalis). J Exp Biol 2013; 216:3208-14. [DOI: 10.1242/jeb.086546] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Summary
The bluefin tuna heart remains at ambient water temperature (Ta) but must supply blood to warm regions of the body served by countercurrent vascular heat exchangers. Despite this unusual physiology, inherent difficulties have precluded an understanding of the cardiovascular responses to Ta in free-swimming bluefin tunas. We measured the heart rate (fH) responses of two captive Pacific bluefin tunas (Thunnus orientalis; 9.7 and 13.3 kg) over a cumulative period of 40 d. Routine fH during fasting in the holding tank at a Ta of 20°C was 45.1±8.0 and 40.7±6.5 beats min-1 for Tuna 1 and Tuna 2, respectively. fH decreased in each fish with Q10 of 2.6 (Tuna 1) and 3.1 (Tuna 2) as Ta in the tank was slowly decreased to 15°C (~0.4oC h-1), despite a gradual increase in swimming speed. The same thermal challenge during digestion revealed similar thermal dependence of fH and indicated that the rate of visceral cooling is not buffered by the heat increment of feeding. Acutely decreasing Ta from 20 to 10°C while Tuna 1 swam in a tunnel respirometer caused a progressive increase in tail beat-frequency and oxygen consumption rate (Mo2). fH of this fish decreased with Q10 of 2.7 as Ta decreased between 20 and 15°C, while further cooling to 10°C saw a general plateau in fH around 35 beats min-1 with Q10 of 1.3. A discussion of the relationships between fH, Mo2 , and haemoglobin-oxygen binding sheds further light on how bluefin cardiorespiratory systems function in a changing thermal environment.
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46
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Bischof R, Loe LE, Meisingset EL, Zimmermann B, Van Moorter B, Mysterud A. A migratory northern ungulate in the pursuit of spring: jumping or surfing the green wave? Am Nat 2012; 180:407-24. [PMID: 22976006 DOI: 10.1086/667590] [Citation(s) in RCA: 256] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The forage-maturation hypothesis (FMH) states that herbivores migrate along a phenological gradient of plant development in order to maximize energy intake. Despite strong support for the FMH, the actual relationship between plant phenology and ungulate movement has remained enigmatic. We linked plant phenology (MODIS-normalized difference vegetation index [NDVI] data) and space use of 167 migratory and 78 resident red deer (Cervus elaphus), using a space-time-time matrix of "springness," defined as the instantaneous rate of green-up. Consistent with the FMH, migrants experienced substantially greater access to early plant phenology than did residents. Deer were also more likely to migrate in areas where migration led to greater gains in springness. Rather than "surfing the green wave" during migration, migratory red deer moved rapidly from the winter to the summer range, thereby "jumping the green wave." However, migrants and, to a lesser degree, residents did track phenological green-up through parts of the growing season by making smaller-scale adjustments in habitat use. Despite pronounced differences in their life histories, we found only marginal differences between male and female red deer in this study. Those differences that we did detect pointed toward additional constraints on female space-use tactics, such as those posed by calving and caring for dependent offspring. We conclude that whereas in some systems migration itself is a way to surf the green wave, in others it may simply be a means to reconnect with phenological spring at the summer range. In the light of ubiquitous anthropogenic environmental change, understanding the relationship between the green wave and ungulate space use has important consequences for the management and conservation of migratory ungulates and the phenomenon of migration itself.
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Affiliation(s)
- Richard Bischof
- Department of Ecology and Natural Resource Management, Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Aas, Norway.
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47
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Queiroz N, Humphries NE, Noble LR, Santos AM, Sims DW. Spatial dynamics and expanded vertical niche of blue sharks in oceanographic fronts reveal habitat targets for conservation. PLoS One 2012; 7:e32374. [PMID: 22393403 PMCID: PMC3290575 DOI: 10.1371/journal.pone.0032374] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Accepted: 01/28/2012] [Indexed: 11/18/2022] Open
Abstract
Dramatic population declines among species of pelagic shark as a result of overfishing have been reported, with some species now at a fraction of their historical biomass. Advanced telemetry techniques enable tracking of spatial dynamics and behaviour, providing fundamental information on habitat preferences of threatened species to aid conservation. We tracked movements of the highest pelagic fisheries by-catch species, the blue shark Prionace glauca, in the North-east Atlantic using pop-off satellite-linked archival tags to determine the degree of space use linked to habitat and to examine vertical niche. Overall, blue sharks moved south-west of tagging sites (English Channel; southern Portugal), exhibiting pronounced site fidelity correlated with localized productive frontal areas, with estimated space-use patterns being significantly different from that of random walks. Tracked female sharks displayed behavioural variability in diel depth preferences, both within and between individuals. Diel depth use ranged from normal DVM (nDVM; dawn descent, dusk ascent), to reverse DVM (rDVM; dawn ascent, dusk descent), to behavioural patterns where no diel differences were apparent. Results showed that blue sharks occupy some of the most productive marine zones for extended periods and structure diel activity patterns across multiple spatio-temporal scales in response to particular habitat types. In so doing, sharks occupied an extraordinarily broad vertical depth range for their size (1.0–2.0 m fork length), from the surface into the bathypelagic realm (max. dive depth, 1160 m). The space-use patterns of blue sharks indicated they spend much of the time in areas where pelagic longlining activities are often highest, and in depth zones where these fisheries particularly target other species, which could account for the rapid declines recently reported for blue sharks in many parts of the world's oceans. Our results provide habitat targets for blue shark conservation that may also be relevant to other pelagic species.
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Affiliation(s)
- Nuno Queiroz
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, United Kingdom
- CIBIO – U.P., Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Rua Padre Armando Quintas, Vairão, Portugal
| | - Nicolas E. Humphries
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, United Kingdom
- School of Marine Science and Engineering, Marine Institute, University of Plymouth, Plymouth, United Kingdom
| | - Leslie R. Noble
- School of Biological Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - António M. Santos
- CIBIO – U.P., Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Rua Padre Armando Quintas, Vairão, Portugal
| | - David W. Sims
- Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth, United Kingdom
- Ocean and Earth Science, National Oceanography Centre, University of Southampton, Waterfront Campus, Southampton, United Kingdom
- Centre for Biological Sciences, University of Southampton, Highfield Campus, Southampton, United Kingdom
- * E-mail:
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48
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Spatio-temporal dynamics of a fish spawning aggregation and its fishery in the Gulf of California. Sci Rep 2012; 2:284. [PMID: 22359736 PMCID: PMC3283881 DOI: 10.1038/srep00284] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Accepted: 02/06/2012] [Indexed: 12/04/2022] Open
Abstract
We engaged in cooperative research with fishers and stakeholders to characterize the fine-scale, spatio-temporal characteristics of spawning behavior in an aggregating marine fish (Cynoscion othonopterus: Sciaenidae) and coincident activities of its commercial fishery in the Upper Gulf of California. Approximately 1.5–1.8 million fish are harvested annually from spawning aggregations of C. othonopterus during 21–25 days of fishing and within an area of 1,149 km2 of a biosphere reserve. Spawning and fishing are synchronized on a semi-lunar cycle, with peaks in both occurring 5 to 2 days before the new and full moon, and fishing intensity and catch are highest at the spawning grounds within a no-take reserve. Results of this study demonstrate the benefits of combining GPS data loggers, fisheries data, biological surveys, and cooperative research with fishers to produce spatio-temporally explicit information relevant to the science and management of fish spawning aggregations and the spatial planning of marine reserves.
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49
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Taylor NG, McAllister MK, Lawson GL, Carruthers T, Block BA. Atlantic bluefin tuna: a novel multistock spatial model for assessing population biomass. PLoS One 2011; 6:e27693. [PMID: 22174745 PMCID: PMC3235089 DOI: 10.1371/journal.pone.0027693] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Accepted: 10/23/2011] [Indexed: 11/18/2022] Open
Abstract
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 benefit from trans-Atlantic cooperation.
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Affiliation(s)
- Nathan G. Taylor
- Fisheries Center, University of
British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
| | - Murdoch K. McAllister
- Fisheries Center, University of
British Columbia, Vancouver, British Columbia, Canada
| | - Gareth L. Lawson
- Department of Biology, Woods Hole
Oceanographic Institution, Woods Hole, Massachusetts, United States of America
| | - Tom Carruthers
- Fisheries Center, University of
British Columbia, Vancouver, British Columbia, Canada
| | - Barbara A. Block
- Hopkins Marine Station, Stanford
University, Pacific Grove, California, United States of America
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Jusup M, Klanjscek T, Matsuda H, Kooijman SALM. A full lifecycle bioenergetic model for bluefin tuna. PLoS One 2011; 6:e21903. [PMID: 21779352 PMCID: PMC3133599 DOI: 10.1371/journal.pone.0021903] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2010] [Accepted: 06/14/2011] [Indexed: 12/30/2022] Open
Abstract
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.
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Affiliation(s)
- Marko Jusup
- Faculty of Environment and Information Sciences, Yokohama National University, Yokohama, Japan.
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