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Porceddu R, Porcu C, Mulas G, Spiga S, Follesa MC. Ontogenetic changes in the tyrosine hydroxylase immunoreactive preoptic area in the small-spotted catshark Scyliorhinus canicula (L., 1758) females: catecholaminergic involvement in sexual maturation. Front Neuroanat 2024; 17:1301651. [PMID: 38239387 PMCID: PMC10794776 DOI: 10.3389/fnana.2023.1301651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 11/29/2023] [Indexed: 01/22/2024] Open
Abstract
Introduction The catecholaminergic component of the brain-pituitary-gonadal axis, which mediates the influence of external and internal stimuli on the central nervous system and gonad development in vertebrates, is largely unexplored in Chondrichthyes. We considered Scyliorhinus canicula (L., 1758) females as a model for this vertebrate's class, to assess the involvement of the catecholaminergic system of the brain in its reproduction. Along the S. canicula reproductive cycle, we characterized and evaluated differences in somata morphometry and the number of putative catecholaminergic neurons in two brain nuclei: the periventricular preoptic nucleus, hypothesized to be a positive control for ovarian development, and the suprachiasmatic nucleus, examined as a negative control. Materials and methods 16 S. canicula wild females were sampled and grouped in maturity stages (immature, maturing, mature, and mature egg-laying). The ovary was histologically processed for the qualitative description of maturity stages. Anti-tyrosine hydroxylase immunofluorescence was performed on the diencephalic brain sections. The immunoreactive somata were investigated for morphometry and counted using the optical fractionator method, throughout the confocal microscopy. Results and discussions Qualitative and quantitative research confirmed two separate populations of immunoreactive neurons. The modifications detected in the preoptic nucleus revealed that somata were more numerous, significantly smaller in size, and more excitable during the maturing phase but decreased, becoming slightly bigger and less excitable in the egg-laying stage. This may indicate that the catecholaminergic preoptic nucleus is involved in the control of reproduction, regulating both the onset of puberty and the imminent spawning. In contrast, somata in the suprachiasmatic nucleus grew in size and underwent turnover in morphometry, increasing the total number from the immature-virgin to maturing stage, with similar values in the more advanced maturity stages. These changes were not linked to a reproductive role. These findings provide new valuable information on Chondrichthyes, suggesting the existence of an additional brain system implicated in the integration of internal and environmental cues for reproduction.
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Affiliation(s)
- Riccardo Porceddu
- Sezione di Biologia Animale ed Ecologia, Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Cagliari, Italy
- CoNISMa Consorzio Nazionale Interuniversitario per le Scienze Mare, Rome, Italy
| | - Cristina Porcu
- Sezione di Biologia Animale ed Ecologia, Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Cagliari, Italy
- CoNISMa Consorzio Nazionale Interuniversitario per le Scienze Mare, Rome, Italy
| | - Giovanna Mulas
- Sezione di Biologia Animale ed Ecologia, Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Cagliari, Italy
| | - Saturnino Spiga
- Sezione di Biologia Animale ed Ecologia, Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Cagliari, Italy
| | - Maria Cristina Follesa
- Sezione di Biologia Animale ed Ecologia, Dipartimento di Scienze della Vita e dell'Ambiente, Università degli Studi di Cagliari, Cagliari, Italy
- CoNISMa Consorzio Nazionale Interuniversitario per le Scienze Mare, Rome, Italy
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Peixoto-Rodrigues MC, da Costa GL, Pinto TN, Adesse D, Oliveira MME, Hauser-Davis RA. A novel report on the emerging and zoonotic neurotropic fungus Trichosporon japonicum in the brain tissue of the endangered Brazilian guitarfish (Pseudobatos horkelii) off the southeastern coast of Brazil. BMC Microbiol 2023; 23:367. [PMID: 38017412 PMCID: PMC10685615 DOI: 10.1186/s12866-023-03128-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 11/17/2023] [Indexed: 11/30/2023] Open
Abstract
Yeast infections have gained significant attention in the field of marine biology in recent years. Among the broad diversity of marine organisms affected by these infections, elasmobranchs (sharks and rays) have emerged as highly susceptible, due to climate change effects, such as increasing water temperatures and pollution, which can alter the composition and abundance of fungal communities. Additionally, injuries, or compromised immune systems resulting from pollution or disease may increase the likelihood of fungal infections in elasmobranchs. Studies are, however, still lacking for this taxonomic group. In this context, this study aimed to screen yeast species in cell cultures obtained from the brain of artisanally captured Pseudobatos horkelii, a cartilaginous fish that, although endangered, is highly captured and consumed worldwide. Fungi were isolated during an attempt to establish primary cultures of elasmobranch neural cells. Culture flasks were swabbed and investigated using morphological, phenotypic, and molecular techniques. Two isolates of the emerging opportunistic pathogen Trichosporon japonicum were identified, with high scores (1.80 and 1.85, respectively) by the MALDI-ToF technique. This is the first report of the basidiomycetous yeast T. japonicum in Pseudobatos horkelii in Brazil. This finding highlights the need for further research to determine the potential impact on elasmobranch health, ecology, as well as on commercial fisheries.
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Affiliation(s)
- Maria Carolina Peixoto-Rodrigues
- Laboratório de Avaliação e Promoção da Saúde Ambiental, IInstituto Oswaldo Cruz, Rio de Janeiro, Brazil
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Gisela Lara da Costa
- Laboratório de Taxonomia, Bioquímica e Bioprospecção de Fungos, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Tatiane Nobre Pinto
- Laboratório de Taxonomia, Bioquímica e Bioprospecção de Fungos, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Daniel Adesse
- Laboratório de Biologia Estrutural, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL, USA
| | | | - Rachel Ann Hauser-Davis
- Laboratório de Avaliação e Promoção da Saúde Ambiental, IInstituto Oswaldo Cruz, Rio de Janeiro, Brazil.
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Le Croizier G, Lorrain A, Hoyos-Padilla M, Ketchum JT, Amezcua-Martínez F, Le Loc'h F, Munaron JM, Schaal G, Point D. Do marine protected areas influence mercury exposure? Insights from a shark community in the tropical Northeast Pacific. Environ Pollut 2023; 336:122352. [PMID: 37562525 DOI: 10.1016/j.envpol.2023.122352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 07/12/2023] [Accepted: 08/08/2023] [Indexed: 08/12/2023]
Abstract
Biomass depletion caused by overfishing is likely to alter the structure of food webs and impact mercury transfer to marine predators. Although marine protected areas (MPAs) are spared from fishing pressure, their influence on biota mercury levels is poorly understood. Here, we used carbon and nitrogen stable isotope compositions as well as mercury concentrations in fin clips to characterize foraging habitat and mercury exposure of a shark community composed of migratory and resident species of the Revillagigedo archipelago, an offshore MPA in the Northeast Pacific off Mexico. We found that the probability of finding migratory sharks in the isotopic niche of Revillagigedo-resident sharks was low, likely reflecting the use of habitats outside the archipelago by highly mobile species. Community-wide variations in mercury were primarily explained by shark length, revealing that bioaccumulation was the main driver of Hg concentrations. We failed to detect a clear effect of foraging habitat on shark mercury exposure, which may be related to migratory species using both exploited and protected areas when moving outside the Revillagigedo MPA. More similar studies on the potential mitigation of Hg contamination by MPAs are needed in the future if fishing pressure increases to satisfy the growing global human population.
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Affiliation(s)
- Gaël Le Croizier
- Instituto de Ciencias Del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Joel Montes Camarena S/N, Mazatlán, Sin, 82040, Mexico.
| | - Anne Lorrain
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, F-29280, Plouzané, France
| | - Mauricio Hoyos-Padilla
- Pelagios-Kakunjá A.C, Sinaloa 1540, Col. Las Garzas, C.P. 23070, La Paz, B.C.S., Mexico; Fins Attached: Marine Research and Conservation, 19675 Still Glen Drive, Colorado Springs, CO 80908, USA
| | - James T Ketchum
- Pelagios-Kakunjá A.C, Sinaloa 1540, Col. Las Garzas, C.P. 23070, La Paz, B.C.S., Mexico; MigraMar, Bodega Bay, CA, USA; Centro de Investigaciones Biológicas Noroeste (CIBNOR), La Paz, B.C.S., Mexico
| | - Felipe Amezcua-Martínez
- Instituto de Ciencias Del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Joel Montes Camarena S/N, Mazatlán, Sin, 82040, Mexico
| | | | | | - Gauthier Schaal
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, F-29280, Plouzané, France
| | - David Point
- UMR Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées (OMP), 14 Avenue Edouard Belin, 31400, Toulouse, France
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Cundy ME, Santana-Garcon J, McLennan AG, Ayad ME, Bayer PE, Cooper M, Corrigan S, Harrison E, Wilcox C. Seafood label quality and mislabelling rates hamper consumer choices for sustainability in Australia. Sci Rep 2023; 13:10146. [PMID: 37537170 PMCID: PMC10400555 DOI: 10.1038/s41598-023-37066-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Accepted: 06/15/2023] [Indexed: 08/05/2023] Open
Abstract
Seafood mislabelling and species substitution, compounded by a convoluted seafood supply chain with significant traceability challenges, hinder efforts towards more sustainable, responsible, and ethical fishing and business practices. We conducted the largest evaluation of the quality and accuracy of labels for 672 seafood products sold in Australia, assessing six seafood groups (i.e., hoki, prawns, sharks and rays, snapper, squid and cuttlefish, and tuna) from fishmongers, restaurants, and supermarkets, including domestically caught and imported products. DNA barcoding revealed 11.8% of seafood tested did not match their label with sharks and rays, and snappers, having the highest mislabelling rate. Moreover, only 25.5% of products were labelled at a species-level, while most labels used vague common names or umbrella terms such as 'flake' and 'snapper'. These poor-quality labels had higher rates of mislabelling than species-specific labels and concealed the sale of threatened or overfished taxa, as well as products with lower nutritional quality, reduced economic value, or potential health risks. Our results highlight Australia's weak seafood labelling regulations and ambiguous non-mandatory naming conventions, which impede consumer choice for accurately represented, sustainable, and responsibly sourced seafood. We recommend strengthening labelling regulations to mitigate seafood mislabelling and substitution, ultimately improving consumer confidence when purchasing seafood.
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Affiliation(s)
- Megan E Cundy
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
| | - Julia Santana-Garcon
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia.
- Centre for Marine Socioecology, University of Tasmania, Hobart, TAS, Australia.
| | | | - Marcelle E Ayad
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
| | - Philipp E Bayer
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
| | - Madalyn Cooper
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
| | - Shannon Corrigan
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
| | - Emily Harrison
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
| | - Chris Wilcox
- Flourishing Oceans Initiative, Minderoo Foundation, Perth, WA, Australia
- Centre for Marine Socioecology, University of Tasmania, Hobart, TAS, Australia
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Landaeta MF, Hernández-Santoro C, Search FV, Castillo MI, Bernal C, Navarrete SA, Wieters EA, Beldade R, Navarro Campoi A, Pérez-Matus A. Spatio-temporal patterns of the crustacean demersal fishery discard from the south Humboldt Current System, based on scientific observer program (2014-2019). PLoS One 2023; 18:e0281932. [PMID: 36848348 PMCID: PMC9970059 DOI: 10.1371/journal.pone.0281932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Accepted: 02/03/2023] [Indexed: 03/01/2023] Open
Abstract
This study summarises six years of spatio-temporal patterns of the discarded demersal community fauna recorded by onboard scientific observer program for both artisanal and industrial crustacean fisheries between 2014 and 2019, from mesophotic to aphotic depths (96 to 650 m) along the southern Humboldt Current System (28-38°S). In this period, one cold and two warm climatic events were observed during the austral summer 2014, 2015-2016 (ENSO Godzilla), and 2016-2017 (coastal ENSO), respectively. Satellite information showed that Chlorophyll-a concentration varied seasonally and latitudinally, associated with upwelling centres, while equatorial wind stress decreased southward of 36°S. Discards were composed of 108 species, dominated by finfish and molluscs. The Chilean hake Merluccius gayi was dominant and ubiquitous (occurrence, 95% of 9104 hauls), being the most vulnerable species of the bycatch. Three assemblages were identified: assemblage 1 (~200 m deep), dominated by flounders Hippoglossina macrops and lemon crabs Platymera gaudichaudii, assemblage 2 (~260 m deep), dominated by squat lobsters Pleuroncodes monodon and Cervimunida johni and assemblage 3 (~320 m depth), dominated by grenadiers Coelorinchus aconcagua and cardinalfish Epigonus crassicaudus. These assemblages were segregated by depth, and varied by year, and geographic zone. The latter represented changes in the width of the continental shelf, increasing southward of 36°S. Alpha-diversity indexes (richness, Shannon, Simpson, and Pielou) also varied with depth and latitude, with higher diversity in deeper continental waters (>300 m), between 2018-2019. Finally, at a spatial scale of tens of kilometres, and a monthly basis, interannual variations of biodiversity occurred in the demersal community. Surface sea temperature, chlorophyll-a, or wind stress did not correlate with discarded demersal fauna diversity of the crustacean fishery operating along central Chile.
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Affiliation(s)
- Mauricio F. Landaeta
- Laboratorio de Ictiología e Interacciones Biofísicas (LABITI), Instituto de Biología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
- Centro de Observación Marino para Estudios del Ambiente Costero (COSTA-R), Universidad de Valparaíso, Viña del Mar, Chile
- * E-mail:
| | - Carola Hernández-Santoro
- Instituto de Fomento Pesquero (IFOP), Valparaíso, Chile
- Programa Doctorado en Ciencias del Mar y Biología Aplicada, University of Alicante, San Vicente del Raspeig, Spain
| | - Francesca V. Search
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
| | - Manuel I. Castillo
- Centro de Observación Marino para Estudios del Ambiente Costero (COSTA-R), Universidad de Valparaíso, Viña del Mar, Chile
- Laboratorio de Oceanografía Física y Satelital (LOFISAT), Escuela de Biología Marina, Universidad de Valparaíso, Viña del Mar, Chile
| | | | - Sergio A. Navarrete
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
- Estación Costera de Investigaciones Marinas, Pontificia Universidad Católica de Chile, Las Cruces, Chile
| | - Evie A. Wieters
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
- Estación Costera de Investigaciones Marinas, Pontificia Universidad Católica de Chile, Las Cruces, Chile
| | - Ricardo Beldade
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
- Estación Costera de Investigaciones Marinas, Pontificia Universidad Católica de Chile, Las Cruces, Chile
| | - Ana Navarro Campoi
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
- Estación Costera de Investigaciones Marinas, Pontificia Universidad Católica de Chile, Las Cruces, Chile
| | - Alejandro Pérez-Matus
- Millennium Nucleus for the Ecology and Conservation of Temperate Mesophotic Reef Ecosystem (NUTME), Las Cruces, Chile
- Departamento de Ecología, Subtidal Ecology Laboratory, Estación Costera de Investigaciones Marinas, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
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Guinot G, Condamine FL. Global impact and selectivity of the Cretaceous-Paleogene mass extinction among sharks, skates, and rays. Science 2023; 379:802-806. [PMID: 36821692 DOI: 10.1126/science.abn2080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
The Cretaceous-Paleogene event was the last mass extinction event, yet its impact and long-term effects on species-level marine vertebrate diversity remain largely uncharacterized. We quantified elasmobranch (sharks, skates, and rays) speciation, extinction, and ecological change resulting from the end-Cretaceous event using >3200 fossil occurrences and 675 species spanning the Late Cretaceous-Paleocene interval at global scale. Elasmobranchs declined by >62% at the Cretaceous-Paleogene boundary and did not fully recover in the Paleocene. The end-Cretaceous event triggered a heterogeneous pattern of extinction, with rays and durophagous species reaching the highest levels of extinction (>72%) and sharks and nondurophagous species being less affected. Taxa with large geographic ranges and/or those restricted to high-latitude settings show higher survival. The Cretaceous-Paleogene event drastically altered the evolutionary history of marine ecosystems.
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Affiliation(s)
- Guillaume Guinot
- Institut des Sciences de l'Évolution de Montpellier, Université de Montpellier, CNRS, IRD, EPHE, Place Eugène Bataillon, 34095 Montpellier, France
| | - Fabien L Condamine
- Institut des Sciences de l'Évolution de Montpellier, Université de Montpellier, CNRS, IRD, EPHE, Place Eugène Bataillon, 34095 Montpellier, France
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Sherman CS, Digel ED, Zubick P, Eged J, Haque AB, Matsushiba JH, Simpfendorfer CA, Sant G, Dulvy NK. High overexploitation risk due to management shortfall in highly traded requiem sharks. Conserv Lett 2023. [DOI: 10.1111/conl.12940] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Affiliation(s)
- C. Samantha Sherman
- Earth to Oceans Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada
- TRAFFIC International Cambridge UK
| | - Eric D. Digel
- Earth to Oceans Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada
| | - Patrick Zubick
- Earth to Oceans Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada
| | - Jonathan Eged
- Earth to Oceans Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada
| | - Alifa B. Haque
- Nature‐Based Solutions Initiative, Department of Zoology University of Oxford Oxford UK
- Department of Zoology University of Dhaka Dhaka Bangladesh
| | - Jay H. Matsushiba
- Earth to Oceans Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada
| | - Colin A. Simpfendorfer
- Institute of Marine and Antarctic Studies University of Tasmania Hobart Tasmania Australia
| | - Glenn Sant
- TRAFFIC International Cambridge UK
- Australian National Centre for Ocean Resources and Security University of Wollongong Wollongong New South Wales Australia
| | - Nicholas K. Dulvy
- Earth to Oceans Research Group, Department of Biological Sciences Simon Fraser University Burnaby British Columbia Canada
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Sherman CS, Simpfendorfer CA, Pacoureau N, Matsushiba JH, Yan HF, Walls RHL, Rigby CL, VanderWright WJ, Jabado RW, Pollom RA, Carlson JK, Charvet P, Bin Ali A, Fahmi, Cheok J, Derrick DH, Herman KB, Finucci B, Eddy TD, Palomares MLD, Avalos-Castillo CG, Kinattumkara B, Blanco-Parra MD, Dharmadi, Espinoza M, Fernando D, Haque AB, Mejía-Falla PA, Navia AF, Pérez-Jiménez JC, Utzurrum J, Yuneni RR, Dulvy NK. Half a century of rising extinction risk of coral reef sharks and rays. Nat Commun 2023; 14:15. [PMID: 36650137 DOI: 10.1038/s41467-022-35091-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 11/17/2022] [Indexed: 01/19/2023] Open
Abstract
Sharks and rays are key functional components of coral reef ecosystems, yet many populations of a few species exhibit signs of depletion and local extinctions. The question is whether these declines forewarn of a global extinction crisis. We use IUCN Red List to quantify the status, trajectory, and threats to all coral reef sharks and rays worldwide. Here, we show that nearly two-thirds (59%) of the 134 coral-reef associated shark and ray species are threatened with extinction. Alongside marine mammals, sharks and rays are among the most threatened groups found on coral reefs. Overfishing is the main cause of elevated extinction risk, compounded by climate change and habitat degradation. Risk is greatest for species that are larger-bodied (less resilient and higher trophic level), widely distributed across several national jurisdictions (subject to a patchwork of management), and in nations with greater fishing pressure and weaker governance. Population declines have occurred over more than half a century, with greatest declines prior to 2005. Immediate action through local protections, combined with broad-scale fisheries management and Marine Protected Areas, is required to avoid extinctions and the loss of critical ecosystem function condemning reefs to a loss of shark and ray biodiversity and ecosystem services, limiting livelihoods and food security.
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Stanhope MJ, Ceres KM, Sun Q, Wang M, Zehr JD, Marra NJ, Wilder AP, Zou C, Bernard AM, Pavinski-Bitar P, Lokey MG, Shivji MS. Genomes of endangered great hammerhead and shortfin mako sharks reveal historic population declines and high levels of inbreeding in great hammerhead. iScience 2023; 26:105815. [PMID: 36632067 DOI: 10.1016/j.isci.2022.105815] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 11/23/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Despite increasing threats of extinction to Elasmobranchii (sharks and rays), whole genome-based conservation insights are lacking. Here, we present chromosome-level genome assemblies for the Critically Endangered great hammerhead (Sphyrna mokarran) and the Endangered shortfin mako (Isurus oxyrinchus) sharks, with genetic diversity and historical demographic comparisons to other shark species. The great hammerhead exhibited low genetic variation, with 8.7% of the 2.77 Gbp genome in runs of homozygosity (ROH) > 1 Mbp and 74.4% in ROH >100 kbp. The 4.98 Gbp shortfin mako genome had considerably greater diversity and <1% in ROH > 1 Mbp. Both these sharks experienced precipitous declines in effective population size (Ne) over the last 250 thousand years. While shortfin mako exhibited a large historical Ne that may have enabled the retention of higher genetic variation, the genomic data suggest a possibly more concerning picture for the great hammerhead, and a need for evaluation with additional individuals.
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Kindong R, Sarr O, Wang J, Xia M, Wu F, Dai L, Tian S, Dai X. Size distribution patterns of silky shark Carcharhinus falciformis shaped by environmental factors in the Pacific Ocean. Sci Total Environ 2022; 850:157927. [PMID: 35963405 DOI: 10.1016/j.scitotenv.2022.157927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 08/05/2022] [Accepted: 08/05/2022] [Indexed: 06/15/2023]
Abstract
Commercial fisheries, especially pelagic longline fisheries targeting tuna and/or swordfish, often land silky sharks (Carcharhinus falciformis), which are currently listed as vulnerable by the International Union for Conservation of Nature (IUCN). Due to increasing fishing effort and the fact that they overlap in habitat with target species, the population trend of silky sharks is declining worldwide. Understanding their relationships with environmental variables that lead to their capture by fisheries is critical for their management and conservation. Nevertheless, little is known about their size distribution in relation to environmental variables in the Pacific Ocean. Using data from the Chinese Observer Tuna Longline fishery from 2010 to 2020, this study developed a species distribution model (SDM) to analyze the relationships between silky shark size distribution patterns and environmental variables and spatio-temporal variability at fishing locations. Observed sizes ranged from 36 to 269 cm fork length (FL). The final model suggests that sea surface temperature (SST), primary production (photosynthetically available radiation, PAR), and ocean surface winds were the key environmental variables shaping size distribution patterns of silky sharks in the Pacific. A high proportion of larger silky sharks has been predicted in areas associated with productive upwelling systems. In addition, the model predicted that larger specimens (>140 cm FL) occur near the equator, and smaller specimens farther from the equator but still in tropical regions. Two regions in the eastern Pacific (the coastal upwelling area off northern Peru and the waters around the Galapagos Islands) seem to be important locations for larger specimens. The size distribution patterns of silky sharks in relation to environmental variables presented in this study illustrate how this species segregates spatially and temporally and presents potential habitat preference areas. The information obtained in the present study is critical in the quest for management and conservation of menaced species such as the silky shark.
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Affiliation(s)
- Richard Kindong
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai 201306, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; Key Laboratory of Oceanic Fisheries Exploitation, Ministry of Agriculture, Shanghai 201306, China; Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of Agriculture, Shanghai 201306, China.
| | - Ousmane Sarr
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
| | - Jiaqi Wang
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai 201306, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; Key Laboratory of Oceanic Fisheries Exploitation, Ministry of Agriculture, Shanghai 201306, China; Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of Agriculture, Shanghai 201306, China
| | - Meng Xia
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai 201306, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; Key Laboratory of Oceanic Fisheries Exploitation, Ministry of Agriculture, Shanghai 201306, China; Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of Agriculture, Shanghai 201306, China
| | - Feng Wu
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai 201306, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; Key Laboratory of Oceanic Fisheries Exploitation, Ministry of Agriculture, Shanghai 201306, China; Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of Agriculture, Shanghai 201306, China
| | - Libin Dai
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
| | - Siquan Tian
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai 201306, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; Key Laboratory of Oceanic Fisheries Exploitation, Ministry of Agriculture, Shanghai 201306, China; Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of Agriculture, Shanghai 201306, China.
| | - Xiaojie Dai
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China; National Engineering Research Center for Oceanic Fisheries, Shanghai Ocean University, Shanghai 201306, China; Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources, Ministry of Education, Shanghai 201306, China; Key Laboratory of Oceanic Fisheries Exploitation, Ministry of Agriculture, Shanghai 201306, China; Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of Agriculture, Shanghai 201306, China
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11
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Cortelezzi P, Paulet TG, Olbers JM, Harris JM, Bernard ATF. Conservation benefits of a marine protected area on South African chondrichthyans. J Environ Manage 2022; 319:115691. [PMID: 35839646 DOI: 10.1016/j.jenvman.2022.115691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/21/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Chondrichthyans are threatened worldwide due to their life-history traits combined with a plethora of anthropogenic impacts that are causing populations to collapse. Marine Protected Areas (MPAs) are a conservation option, but their efficacy for chondrichthyans is still unclear. Conservation efforts might be challenging especially in developing countries, due to a lack of resources and monitoring and limited data and stakeholder support. Here Baited Remote Underwater Stereo-Video systems (stereo-BRUVs) were deployed inside and outside a small partially protected MPA (Robberg MPA, Western Cape, South Africa) to assess the status of cartilaginous fishes' assemblages and to investigate the potential benefits derived from the presence of a marine reserve. Overall, 19 chondrichthyan species in 11 different families were observed. Chondrichthyans were observed in 78.5% of the sites and, of these, 89.7% of the MPA sites showed at least one chondrichthyan, while only in the 67.5% of surrounding exploited sites a cartilaginous fish was sighted. The presence of the MPA had a significant effect on the relative abundance of batoids, threatened species and local endemics, with more observations inside the MPA than outside, indicating the potential benefit of marine reserves on species that are more vulnerable to fishing pressure. Relative abundance was generally higher inside the bay than in the exposed area, and both relative abundance and species richness decreased significantly with depth. The analysis of the body length showed that the 35.5% of species had an average body length below maturity length, indicating that the area might be used as nursery ground for different species. This study provides evidence that MPAs, even though small and partially protected, can provide benefits for chondrichthyans, specifically to threatened species, endemic species and lesser-known species. Importantly, different environmental parameters must be considered to maximize the benefits an MPA can provide.
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Affiliation(s)
- Paolo Cortelezzi
- Earth and Environmental Science Department, University of Milano Bicocca, Piazza Della Scienza 1, 20126, Milano, Italy; South African Shark Conservancy (SASC), Hermanus, 7200, Western Cape, South Africa.
| | - Timothy G Paulet
- South African Shark Conservancy (SASC), Hermanus, 7200, Western Cape, South Africa
| | - Jennifer M Olbers
- Wildlands Conservation Trust, 460 Townbush Road, Pietermaritzburg, 3201, South Africa
| | - Jean M Harris
- Wildlands Conservation Trust, 460 Townbush Road, Pietermaritzburg, 3201, South Africa; Institute for Coastal and Marine Research (CMR), Nelson Mandela University, Gomeroy Avenue, Summerstrand, Port Elizabeth 6031, South Africa
| | - Anthony T F Bernard
- South African Institute for Aquatic Biodiversity, Somerset Street, Makhanda, 6139, South Africa; Rhodes University, Department of Zoology and Entomology, Makhanda, 6139, South Africa
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12
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Di Lorenzo M, Calò A, Di Franco A, Milisenda G, Aglieri G, Cattano C, Milazzo M, Guidetti P. Small-scale fisheries catch more threatened elasmobranchs inside partially protected areas than in unprotected areas. Nat Commun 2022; 13:4381. [PMID: 35945205 PMCID: PMC9363485 DOI: 10.1038/s41467-022-32035-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 07/11/2022] [Indexed: 11/09/2022] Open
Abstract
Elasmobranchs are heavily impacted by fishing. Catch statistics are grossly underestimated due to missing data from various fishery sectors such as small-scale fisheries. Marine Protected Areas are proposed as a tool to protect elasmobranchs and counter their ongoing depletion. We assess elasmobranchs caught in 1,256 fishing operations with fixed nets carried out in partially protected areas within Marine Protected Areas and unprotected areas beyond Marine Protected Areas borders at 11 locations in 6 Mediterranean countries. Twenty-four elasmobranch species were recorded, more than one-third belonging to the IUCN threatened categories (Vulnerable, Endangered, or Critically Endangered). Catches per unit of effort of threatened and data deficient species were higher (with more immature individuals being caught) in partially protected areas than in unprotected areas. Our study suggests that despite partially protected areas having the potential to deliver ecological benefits for threatened elasmobranchs, poor small-scale fisheries management inside Marine Protected Areas could hinder them from achieving this important conservation objective.
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Affiliation(s)
- Manfredi Di Lorenzo
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine Ecology, Sicily Marine Center, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy.
| | - Antonio Calò
- Department of Earth and Marine sciences (DiSTeM), University of Palermo, Via Archirafi 20-22, 90123, Palermo, Italy
| | - Antonio Di Franco
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine Ecology, Sicily Marine Center, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy.
| | - Giacomo Milisenda
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine Ecology, Sicily Marine Center, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy
| | - Giorgio Aglieri
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine Ecology, Sicily Marine Center, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy
- Department of Earth and Marine sciences (DiSTeM), University of Palermo, Via Archirafi 20-22, 90123, Palermo, Italy
- CoNISMa, Piazzale Flaminio 9, 00196, Rome, Italy
| | - Carlo Cattano
- Stazione Zoologica Anton Dohrn, Department of Integrative Marine Ecology, Sicily Marine Center, Lungomare Cristoforo Colombo (complesso Roosevelt), 90149, Palermo, Italy
- Department of Earth and Marine sciences (DiSTeM), University of Palermo, Via Archirafi 20-22, 90123, Palermo, Italy
- CoNISMa, Piazzale Flaminio 9, 00196, Rome, Italy
| | - Marco Milazzo
- Department of Earth and Marine sciences (DiSTeM), University of Palermo, Via Archirafi 20-22, 90123, Palermo, Italy
- CoNISMa, Piazzale Flaminio 9, 00196, Rome, Italy
| | - Paolo Guidetti
- Department of Integrative Marine Ecology (EMI), Stazione Zoologica Anton Dohrn-National Institute of Marine Biology, Ecology and Biotechnology, Genoa Marine Centre, 16126, Genoa, Italy
- National Research Council, Institute for the Study of Anthropic Impact and sustainability in the Marine Environment (CNR-IAS), Via de Marini 6, 16149, Genova, Italy
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13
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Wang C, Lai T, Ye P, Yan Y, Feutry P, He B, Huang Z, Zhu T, Wang J, Chen X. Novel duplication remnant in the first complete mitogenome of Hemitriakis japanica and the unique phylogenetic position of family Triakidae. Gene 2022; 820:146232. [PMID: 35114282 DOI: 10.1016/j.gene.2022.146232] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/22/2021] [Accepted: 01/18/2022] [Indexed: 01/08/2023]
Abstract
In this study, we firstly determined the complete mitogenome of the Japanese topeshark (Hemitriakis japonica), which belong to the family Triakidae and was assessed as Endangered A2d on the IUCN Red List in 2021. The mitogenome is 17,301 bp long, has a high AT content (60.0%), and contains 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, a control region and specially a 594 bp-long non-coding region between Cytb gene and tRNA-Thr gene. The novel non-coding region share high sequence similarity with segments of the former and latter genes, so it was recognized as a duplication remnant. In addition, the Cytb gene and tRNA-Thr gene tandemly duplicated twice while accompanied by being deleted once at least. This is the first report of mitogenomic gene-arrangement in Triakidae. The phylogenetic trees were constructed using Bayesian inference (BI) and maximum likelihood (ML) methods based on the mitogenomic data of 51 shark species and two outgroups. In summary, basing on a novel type of gene rearrangements in houndshark mitogenome, the possibly rearranged process was analyzed and contributed further insight of shark mitogenomes evolution and phylogeny.
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Affiliation(s)
- Chen Wang
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China
| | - Tinghe Lai
- Guangxi Academy of Oceanography, Nanning 530000, China
| | - Peiyuan Ye
- College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China
| | - Yunrong Yan
- College of Fisheries, Guangdong Ocean University, Zhanjiang 524000, China
| | - Pierre Feutry
- CSIRO Oceans and Atmosphere, Castray Esplanade, Hobart, Tasmania 7000, Australia
| | - Binyuan He
- Guangxi Academy of Oceanography, Nanning 530000, China
| | | | - Ting Zhu
- Guangxi Academy of Oceanography, Nanning 530000, China
| | - Junjie Wang
- Guangzhou Key Laboratory of Subtropical Biodiversity and Biomonitoring, School of Life Sciences, South China Normal University, Guangzhou 510631, China.
| | - Xiao Chen
- College of Marine Sciences, South China Agriculture University, Guangzhou 510642, China; Guangxi Mangrove Research Center, Beihai 536000, China.
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14
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Erguden D, Kabasakal H, Ayas D. Fisheries bycatch and conservation priorities of young sharks (Chondrichthyes: Elasmobranchii) in the Eastern Mediterranean. Zoology in the Middle East 2022. [DOI: 10.1080/09397140.2022.2051916] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Deniz Erguden
- Marine Sciences Department, Marine Sciences and Technology Faculty, İskenderun Technical University, İskenderun, Hatay, Turkey
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15
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Le Croizier G, Sonke JE, Lorrain A, Renedo M, Hoyos-Padilla M, Santana-Morales O, Meyer L, Huveneers C, Butcher P, Amezcua-Martinez F, Point D. Foraging plasticity diversifies mercury exposure sources and bioaccumulation patterns in the world's largest predatory fish. J Hazard Mater 2022; 425:127956. [PMID: 34986563 DOI: 10.1016/j.jhazmat.2021.127956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 11/16/2021] [Accepted: 11/28/2021] [Indexed: 05/04/2023]
Abstract
Large marine predators exhibit high concentrations of mercury (Hg) as neurotoxic methylmercury, and the potential impacts of global change on Hg contamination in these species remain highly debated. Current contaminant model predictions do not account for intraspecific variability in Hg exposure and may fail to reflect the diversity of future Hg levels among conspecific populations or individuals, especially for top predators displaying a wide range of ecological traits. Here, we used Hg isotopic compositions to show that Hg exposure sources varied significantly between and within three populations of white sharks (Carcharodon carcharias) with contrasting ecology: the north-eastern Pacific, eastern Australasian, and south-western Australasian populations. Through Δ200Hg signatures in shark tissues, we found that atmospheric Hg deposition pathways to the marine environment differed between coastal and offshore habitats. Discrepancies in δ202Hg and Δ199Hg signatures among white sharks provided evidence for intraspecific exposure to distinct sources of marine methylmercury, attributed to population and ontogenetic shifts in foraging habitat and prey composition. We finally observed a strong divergence in Hg accumulation rates between populations, leading to three times higher Hg concentrations in large Australasian sharks compared to north-eastern Pacific sharks, and likely due to different trophic strategies adopted by adult sharks across populations. This study illustrates the variety of Hg exposure sources and bioaccumulation patterns that can be found within a single species and suggests that intraspecific variability needs to be considered when assessing future trajectories of Hg levels in marine predators.
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Affiliation(s)
- Gaël Le Croizier
- UMR Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées (OMP), 14 avenue Edouard Belin, 31400 Toulouse, France; Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Joel Montes Camarena S/N, Mazatlán, Sin 82040, Mexico.
| | - Jeroen E Sonke
- UMR Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées (OMP), 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Anne Lorrain
- Univ Brest, CNRS, IRD, Ifremer, LEMAR, F-29280 Plouzané, France
| | - Marina Renedo
- UMR Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées (OMP), 14 avenue Edouard Belin, 31400 Toulouse, France
| | - Mauricio Hoyos-Padilla
- Pelagios-Kakunjá A.C, Sinaloa 1540, Col. Las Garzas, C.P. 23070 La Paz, B.C.S., Mexico; Fins Attached: Marine Research and Conservation, 19675 Still Glen Drive, Colorado Springs, CO 80908, USA
| | | | - Lauren Meyer
- Southern Shark Ecology Group, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia; Georgia Aquarium, Atlanta, GA 30313, USA
| | - Charlie Huveneers
- Southern Shark Ecology Group, College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia
| | - Paul Butcher
- NSW Department of Primary Industries, National Marine Science Centre, Coffs Harbour, NSW 2450, Australia
| | - Felipe Amezcua-Martinez
- Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Joel Montes Camarena S/N, Mazatlán, Sin 82040, Mexico
| | - David Point
- UMR Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées (OMP), 14 avenue Edouard Belin, 31400 Toulouse, France
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16
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Dunn RE, Bradley D, Heithaus MR, Caselle JE, Papastamatiou YP. Conservation implications of forage base requirements of a marine predator population at carrying capacity. iScience 2022; 25:103646. [PMID: 35024583 PMCID: PMC8728395 DOI: 10.1016/j.isci.2021.103646] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/29/2021] [Accepted: 12/14/2021] [Indexed: 11/16/2022] Open
Abstract
Prey depletion may contribute to marine predator declines, yet the forage base required to sustain an unfished population of predatory fish at carrying capacity is unknown. We integrated demographic and physiological data within a Bayesian bioenergetic model to estimate annual consumption of a gray reef shark (Carcharhinus amblyrhynchos) population at a remote Pacific atoll (Palmyra Atoll) that are at carrying capacity. Furthermore, we estimated the proportion of the atoll's reef fish biomass production consumed by the gray reef sharks, assuming sharks either partially foraged pelagically (mean 7%), or solely within the reef environment (mean 52%). We then predicted the gray reef shark population potential of other, less remote Pacific Ocean coral reef islands, illustrating that current populations are substantially smaller than could be supported by their forage base. Our research highlights the utility of modeling how far predator population sizes are from their expected carrying capacity in informing marine conservation. Diet impacts the consumptive influence of gray reef sharks on reef fish resources Some gray reef shark populations could be larger, considering their forage base Modeling potential predator population sizes can inform their conservation
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Affiliation(s)
- Ruth E Dunn
- Institute of Environment, Department of Biological Sciences, Florida International University, Miami, FL, USA.,Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Darcy Bradley
- Marine Science Institute, University of California, Santa Barbara, CA, USA
| | - Michael R Heithaus
- Institute of Environment, Department of Biological Sciences, Florida International University, Miami, FL, USA
| | - Jennifer E Caselle
- Marine Science Institute, University of California, Santa Barbara, CA, USA
| | - Yannis P Papastamatiou
- Institute of Environment, Department of Biological Sciences, Florida International University, Miami, FL, USA
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17
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Larson S, Lowry D, Dulvy NK, Wharton J, Galván-Magaña F, Sianipar AB, Lowe CG, Meyer E. Current and future considerations for shark conservation in the Northeast and Eastern Central Pacific Ocean. Adv Mar Biol 2021; 90:1-49. [PMID: 34728053 DOI: 10.1016/bs.amb.2021.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Sharks are iconic and ecologically important predators found in every ocean. Because of their ecological role as predators, some considered apex predators, and concern over the stability of their populations due to direct and indirect overfishing, there has been an increasing amount of work focussed on shark conservation, and other elasmobranchs such as skates and rays, around the world. Here we discuss many aspects of current shark science and conservation and the path to the future of shark conservation in the Northeastern and Eastern Central Pacific. We explore their roles in ecosystems as keystone species; the conservation measures and laws in place at the international, national, regional and local level; the conservation status of sharks and rays in the region, fisheries for sharks in the Northcentral Pacific specifically those that target juveniles and the implications to shark conservation; a conservation success story: the recovery of Great White Sharks in the Northeast Pacific; public perceptions of sharks and the roles zoos and aquariums play in shark conservation; and the path to the future of shark conservation that requires bold partnerships, local stakeholders and innovative measures.
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Affiliation(s)
- Shawn Larson
- Seattle Aquarium, Conservation Programs and Partnerships, Seattle, WA, United States.
| | - Dayv Lowry
- National Marine Fisheries Service, West Coast Region, Protected Resources Division, Lacey, WA, United States
| | - Nicholas K Dulvy
- Earth to Ocean Research Group, Department of Biological Sciences, Simon Fraser University, Burnaby, BC, Canada
| | - Jim Wharton
- Seattle Aquarium, Conservation Engagement and Learning, Seattle, WA, United States
| | - Felipe Galván-Magaña
- Instituto Politécnico National, Centro Interdisciplinario de Ciencias Marinas, La Paz, Baja California Sur, Mexico
| | - Abraham B Sianipar
- Murdoch University, School of Veterinary and Life Sciences, Perth, WA, Australia
| | - Christopher G Lowe
- California State University Long Beach Shark Lab, Long Beach, CA, United States
| | - Erin Meyer
- Seattle Aquarium, Conservation Programs and Partnerships, Seattle, WA, United States
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