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Nicole SA, Fernanda ZC, Mendoza-Nieto K, Briones-Mendoza J. Age and growth of the blue shark Prionace glauca (Linnaeus, 1758) in the Ecuadorian Pacific: Bayesian multi-models. JOURNAL OF FISH BIOLOGY 2024. [PMID: 38622835 DOI: 10.1111/jfb.15755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2023] [Revised: 03/12/2024] [Accepted: 03/31/2024] [Indexed: 04/17/2024]
Abstract
The blue shark Prionace glauca plays a critical role as a predator in marine ecosystems but is threatened by by-catch. To obtain more precise biological data, a Bayesian approach was used, and 536 vertebrae samples collected during 1 year at the landing stage called "Playita Mía" Manta, Ecuador, were analysed. The objective was to estimate the age and growth parameters of the species. The size of the specimens varied between 116 and 310 cm in total length (TL). Using a Bayesian approach based on the Markov Chain Monte Carlo (MCMC) method, growth parameters were evaluated. The von Bertalanffy model was the one that best fitted the data and provided more adequate estimates (females:L ∞ $$ L\infty $$ = 325.50 cm,L 0 $$ {L}_0 $$ = 53.23 cm, and k = 0.12 years; males:L ∞ $$ L\infty $$ = 331.47 cm,L 0 $$ {L}_0 $$ = 51.59 cm, k = 0.12 years -1; combined sexes:L ∞ $$ L\infty $$ = 329.65 cm,L 0 $$ {L}_0 $$ = 53.64 cm, k = 0.11 year-1). The results indicated that females and males have a similar growth, and that the species has a slow growth. Further studies using multi-model Bayesian approaches and covering a broader range of sizes in the Pacific Ocean are suggested. These studies will provide crucial information for the management and conservation of this species.
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Affiliation(s)
- Suárez-Aguilar Nicole
- Carrera de Biología, Facultad de Ciencias de la Vida y Tecnologías, Universidad Laica "Eloy Alfaro" de Manabí, Ciudadela Universitaria vía San Mateo, Manta, Ecuador
| | - Zambrano-Cedeño Fernanda
- Carrera de Biología, Facultad de Ciencias de la Vida y Tecnologías, Universidad Laica "Eloy Alfaro" de Manabí, Ciudadela Universitaria vía San Mateo, Manta, Ecuador
| | - Klever Mendoza-Nieto
- Carrera de Biología, Facultad de Ciencias de la Vida y Tecnologías, Universidad Laica "Eloy Alfaro" de Manabí, Ciudadela Universitaria vía San Mateo, Manta, Ecuador
| | - Jesus Briones-Mendoza
- Carrera de Biología, Facultad de Ciencias de la Vida y Tecnologías, Universidad Laica "Eloy Alfaro" de Manabí, Ciudadela Universitaria vía San Mateo, Manta, Ecuador
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2
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Klein JD, Maduna SN, Dicken ML, da Silva C, Soekoe M, McCord ME, Potts WM, Hagen SB, Bester‐van der Merwe AE. Local adaptation with gene flow in a highly dispersive shark. Evol Appl 2024; 17:e13628. [PMID: 38283610 PMCID: PMC10810256 DOI: 10.1111/eva.13628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/06/2023] [Accepted: 11/27/2023] [Indexed: 01/30/2024] Open
Abstract
Adaptive divergence in response to environmental clines are expected to be common in species occupying heterogeneous environments. Despite numerous advances in techniques appropriate for non-model species, gene-environment association studies in elasmobranchs are still scarce. The bronze whaler or copper shark (Carcharhinus brachyurus) is a large coastal shark with a wide distribution and one of the most exploited elasmobranchs in southern Africa. Here, we assessed the distribution of neutral and adaptive genomic diversity in C. brachyurus across a highly heterogeneous environment in southern Africa based on genome-wide SNPs obtained through a restriction site-associated DNA method (3RAD). A combination of differentiation-based genome-scan (outflank) and genotype-environment analyses (redundancy analysis, latent factor mixed models) identified a total of 234 differentiation-based outlier and candidate SNPs associated with bioclimatic variables. Analysis of 26,299 putatively neutral SNPs revealed moderate and evenly distributed levels of genomic diversity across sites from the east coast of South Africa to Angola. Multivariate and clustering analyses demonstrated a high degree of gene flow with no significant population structuring among or within ocean basins. In contrast, the putatively adaptive SNPs demonstrated the presence of two clusters and deep divergence between Angola and all other individuals from Namibia and South Africa. These results provide evidence for adaptive divergence in response to a heterogeneous seascape in a large, mobile shark despite high levels of gene flow. These results are expected to inform management strategies and policy at the national and regional level for conservation of C. brachyurus populations.
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Affiliation(s)
- Juliana D. Klein
- Molecular Breeding and Biodiversity Research Group, Department of GeneticsStellenbosch UniversityStellenboschSouth Africa
| | - Simo N. Maduna
- Department of Ecosystems in the Barents Region, Svanhovd Research StationNorwegian Institute of Bioeconomy Research—NIBIOSvanvikNorway
| | - Matthew L. Dicken
- KwaZulu‐Natal Sharks BoardUmhlanga RocksSouth Africa
- Institute for Coastal and Marine Research (CMR), Ocean Sciences CampusNelson Mandela UniversityGqeberhaSouth Africa
| | - Charlene da Silva
- Department of Forestry, Fisheries and EnvironmentRogge BaySouth Africa
| | - Michelle Soekoe
- Division of Marine ScienceReel Science CoalitionCape TownSouth Africa
| | - Meaghen E. McCord
- South African Shark ConservancyHermanusSouth Africa
- Canadian Parks and Wilderness SocietyVancouverBritish ColumbiaCanada
| | - Warren M. Potts
- Department of Ichthyology and Fisheries ScienceRhodes UniversityMakhandaSouth Africa
- South African Institute for Aquatic BiodiversityMakhandaSouth Africa
| | - Snorre B. Hagen
- Department of Ecosystems in the Barents Region, Svanhovd Research StationNorwegian Institute of Bioeconomy Research—NIBIOSvanvikNorway
| | - Aletta E. Bester‐van der Merwe
- Molecular Breeding and Biodiversity Research Group, Department of GeneticsStellenbosch UniversityStellenboschSouth Africa
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3
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Li CYJ, Tsai WP, Ranatunga RRMKP, Samidon M, Liu SYV. Genetic stock structure of the silky shark Carcharhinus falciformis in the Indo-Pacific Ocean. PLoS One 2023; 18:e0292743. [PMID: 37824585 PMCID: PMC10569576 DOI: 10.1371/journal.pone.0292743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 09/27/2023] [Indexed: 10/14/2023] Open
Abstract
The silky shark, Carcharhinus falciformis, is a cosmopolitan species commonly caught as a bycatch for longline fisheries. However, the genetic stock structure for the Indo-Pacific Ocean is not well-defined yet. Here, we used eight microsatellite loci to examine the genetic stock structure and effective population size of 307 silky sharks across 5 Indo-Pacific sampling locations. A major genetic break was found between Aceh and the remaining locations (FST = 0.0505-0.0828, p = 0.001). The Indian Ocean displayed a slightly lower effective population estimate (Ne) compared to the Pacific Ocean, potentially due to the higher fishing pressure in the Indian Ocean region. The lowest Ne was found in the Aceh population (Ne = 2.3), suggesting it might be a small and endemic population. These findings offer valuable information for the conservation and management of the silky shark. We suggest that the population around Aceh waters constitutes a distinct stock and should be managed independently. Further investigations into migratory and movement patterns are needed to define the boundaries of different stocks, ensuring effective management the silky shark across the Indo-Pacific region.
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Affiliation(s)
- Chia-Yun Joanne Li
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Wen-Pei Tsai
- Department of Fisheries Production and Management, National Kaohsiung University of Science and Technology, Kaohsiung, Taiwan
| | - R. R. M. K. P. Ranatunga
- Centre for Marine Science and Technology, Department of Zoology, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Munandar Samidon
- Department of Marine Science, Teuku Umar University, Aceh Barat, Indonesia
| | - Shang Yin Vanson Liu
- Department of Marine Biotechnology and Resources, National Sun Yat-sen University, Kaohsiung, Taiwan
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4
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Hirschfeld M, Barnett A, Sheaves M, Dudgeon C. What Darwin could not see: island formation and historical sea levels shape genetic divergence and island biogeography in a coastal marine species. Heredity (Edinb) 2023; 131:189-200. [PMID: 37400518 PMCID: PMC10462691 DOI: 10.1038/s41437-023-00635-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2022] [Revised: 06/12/2023] [Accepted: 06/13/2023] [Indexed: 07/05/2023] Open
Abstract
Oceanic islands play a central role in the study of evolution and island biogeography. The Galapagos Islands are one of the most studied oceanic archipelagos but research has almost exclusively focused on terrestrial organisms compared to marine species. Here we used the Galapagos bullhead shark (Heterodontus quoyi) and single nucleotide polymorphisms (SNPs) to examine evolutionary processes and their consequences for genetic divergence and island biogeography in a shallow-water marine species without larval dispersal. The sequential separation of individual islands from a central island cluster gradually established different ocean depths between islands that pose barriers to dispersal in H. quoyi. Isolation by resistance analysis suggested that ocean bathymetry and historical sea level fluctuations modified genetic connectivity. These processes resulted in at least three genetic clusters that exhibit low genetic diversity and effective population sizes that scale with island size and the level of geographic isolation. Our results exemplify that island formation and climatic cycles shape genetic divergence and biogeography of coastal marine organisms with limited dispersal comparable to terrestrial taxa. Because similar scenarios exist in oceanic islands around the globe our research provides a new perspective on marine evolution and biogeography with implications for the conservation of island biodiversity.
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Affiliation(s)
- Maximilian Hirschfeld
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia.
- Galápagos Science Center, Universidad San Francisco de Quito, Isla San Cristóbal, Galápagos, Ecuador.
| | - Adam Barnett
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Marine Data Technology Hub, James Cook University, Townsville, Queensland, Australia
- Biopixel Oceans Foundation, Cairns, Queensland, Australia
| | - Marcus Sheaves
- College of Science and Engineering, James Cook University, Townsville, Queensland, Australia
- Marine Data Technology Hub, James Cook University, Townsville, Queensland, Australia
| | - Christine Dudgeon
- Biopixel Oceans Foundation, Cairns, Queensland, Australia
- School of Biomedical Sciences, The University of Queensland, Saint Lucia, Queensland, Australia
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5
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Kottillil S, Rao C, Bowen BW, Shanker K. Phylogeography of sharks and rays: a global review based on life history traits and biogeographic partitions. PeerJ 2023; 11:e15396. [PMID: 37283899 PMCID: PMC10239618 DOI: 10.7717/peerj.15396] [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: 06/13/2022] [Accepted: 04/20/2023] [Indexed: 06/08/2023] Open
Abstract
Considerable research exists on the life history traits, evolutionary history, and environmental factors that shape the population genetic structure of marine organisms, including sharks and rays. Conservation concerns are particularly strong for this group as they are highly susceptible to anthropogenic stressors due to a combination of life history traits including late maturity and low fecundity. Here, we provide a review and synthesis of the global phylogeography of sharks and rays. We examined existing data for 40 species of sharks belonging to 17 genera and 19 species of rays belonging to 11 genera. Median joining haplotype networks were constructed for each species for the mtDNA cytochrome C oxidase subunit I (COI), and an Analysis of Molecular Variance (AMOVA) was conducted to understand patterns of genetic diversity and structure across the three major ocean basins-the Indian, Atlantic and Pacific Oceans. Haplotype networks showed very shallow coalescence in most species, a finding previously reported for marine teleosts. Star topologies were predominant among sharks while complex mutational topologies predominated among rays, a finding we attribute to extremely limited dispersal in the early life history of rays. Population structuring varied amongst species groups, apparently due to differences in life history traits including reproductive philopatry, site fidelity, pelagic habitat, migratory habits, and dispersal ability. In comparison to reef-associated and demersal species, pelagic and semi pelagic species showed lower levels of structure between and within ocean basins. As expected, there is variation between taxa and groups, but there are also some broad patterns that can guide management and conservation strategies.
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Affiliation(s)
- Sudha Kottillil
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
- Department of Energy and Environment, TERI School of Advanced Studies, New Delhi, India
| | - Chetan Rao
- Dakshin Foundation, Bengaluru, Karnataka, India
| | - Brian W. Bowen
- Hawai‘i Institute of Marine Biology, University of Hawaii, Kaneohe, Hawai‘i, United States of America
| | - Kartik Shanker
- Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, Karnataka, India
- Dakshin Foundation, Bengaluru, Karnataka, India
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6
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Mucientes G, Fernández‐Chacón A, Queiroz N, Sims DW, Villegas‐Ríos D. Juvenile survival and movements of two threatened oceanic sharks in the North Atlantic Ocean inferred from tag-recovery data. Ecol Evol 2023; 13:e10198. [PMID: 37351477 PMCID: PMC10283031 DOI: 10.1002/ece3.10198] [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: 03/14/2023] [Revised: 05/25/2023] [Accepted: 05/30/2023] [Indexed: 06/24/2023] Open
Abstract
Understanding population dynamics, movements, and fishing mortality is critical to establish effective shark conservation measures across international boundaries in the ocean. There are few survival and dispersal estimates of juveniles of oceanic shark species in the North Atlantic despite it being one of the most fished regions in the world. Here we provide estimates of dispersal, survival, and proportion of fishing mortality in the North Atlantic for two threatened oceanic sharks: the blue shark (Prionace glauca) and the shortfin mako shark (Isurus oxyrinchus). Our results are based on multi-event models applied to tag-recovery data of 700 blue sharks and 132 shortfin makos tagged over a decade. A total of 60 blue sharks (8.57% of tagged) and 30 makos (22.73%) were recovered by the longline fishery between 2009 and 2017. Tag-reporting rate (percentage of returned information when a tagged shark was caught) was estimated to be high (0.794 ± 0.232 SE). Mean annual survival, as predicted from the models, was higher for blue shark (0.835 ± 0.040 SE) than for shortfin mako (0.618 ± 0.189 SE). Models predicted that fishing caused more than a half of total mortality in the study area for both species (0.576 ± 0.209), and more than a third of tagged individuals dispersed from the study area permanently (0.359 ± 0.073). Our findings, focused mainly on juveniles from oceanic areas, contribute to a better understanding of shark population dynamics in the North Atlantic and highlight the need for further conservation measures for both blue shark and shortfin mako, such as implementing efficient bycatch mitigation measures and static/dynamic time-area closures in the open ocean.
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Affiliation(s)
- Gonzalo Mucientes
- Instituto de Investigaciones Marinas, Consejo Superior de Investigaciones Científicas (IIM‐CSIC)VigoSpain
- Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado (CIBIO‐InBIO)Universidade do PortoVairãoPortugal
- BIOPOLIS Program in Genomics, Biodiversity and Land PlanningCIBIOVairãoPortugal
| | - Albert Fernández‐Chacón
- Department of Natural Sciences, Centre for Coastal ResearchUniversity of AgderKristiansandNorway
- North Atlantic Marine Mammal CommissionTromsøNorway
| | - Nuno Queiroz
- Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO Laboratório Associado (CIBIO‐InBIO)Universidade do PortoVairãoPortugal
- BIOPOLIS Program in Genomics, Biodiversity and Land PlanningCIBIOVairãoPortugal
| | - David W. Sims
- Marine Biological AssociationPlymouthUK
- Ocean and Earth Science, National Oceanography Centre SouthamptonUniversity of SouthamptonSouthamptonUK
| | - David Villegas‐Ríos
- Instituto de Investigaciones Marinas, Consejo Superior de Investigaciones Científicas (IIM‐CSIC)VigoSpain
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7
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Nikolic N, Devloo-Delva F, Bailleul D, Noskova E, Rougeux C, Delord C, Borsa P, Liautard-Haag C, Hassan M, Marie AD, Feutry P, Grewe P, Davies C, Farley J, Fernando D, Biton-Porsmoguer S, Poisson F, Parker D, Leone A, Aulich J, Lansdell M, Marsac F, Arnaud-Haond S. Stepping up to genome scan allows stock differentiation in the worldwide distributed blue shark Prionace glauca. Mol Ecol 2023; 32:1000-1019. [PMID: 36511846 DOI: 10.1111/mec.16822] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 11/29/2022] [Accepted: 12/01/2022] [Indexed: 12/15/2022]
Abstract
The blue shark Prionace glauca is a top predator with one of the widest geographical distributions of any shark species. It is classified as Critically Endangered in the Mediterranean Sea, and Near Threatened globally. Previous genetic studies did not reject the null hypothesis of a single global population. The blue shark was proposed as a possible archetype of the "grey zone of population differentiation," coined to designate cases where population structure may be too recent or too faint to be detected using a limited set of markers. Here, blue shark samples collected throughout its global range were sequenced using a specific RAD method (DArTseq), which recovered 37,655 genome-wide single nucleotide polymorphisms (SNPs). Two main groups emerged, with Mediterranean Sea and northern Atlantic samples (Northern population) differentiated significantly from the Indo-west Pacific samples (Southern population). Significant pairwise FST values indicated further genetic differentiation within the Atlantic Ocean, and between the Atlantic Ocean and the Mediterranean Sea. Reconstruction of recent demographic history suggested divergence between Northern and Southern populations occurred about 500 generations ago and revealed a drastic reduction in effective population size from a large ancestral population. Our results illustrate the power of genome scans to detect population structure and reconstruct demographic history in highly migratory marine species. Given that the management plans of the blue shark (targeted or bycatch) fisheries currently assume panmictic regional stocks, we strongly recommend that the results presented here be considered in future stock assessments and conservation strategies.
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Affiliation(s)
- Natacha Nikolic
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France.,INRAE, Ecobiop, AQUA, Saint-Pée-sur-Nivelle, France.,ARBRE, Agence de Recherche pour la Biodiversité à la Réunion, Saint-Gilles, France
| | - Floriaan Devloo-Delva
- CSIRO Environment, Hobart, Tasmania, Australia.,School of Natural Sciences-Quantitative Marine Science, University of Tasmania, Hobart, Tasmania, Australia
| | - Diane Bailleul
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France
| | - Ekaterina Noskova
- Computer Technologies Laboratory, ITMO University, St Petersburg, Russia
| | | | - Chrystelle Delord
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France
| | - Philippe Borsa
- Institut de recherche pour le développement, UMR ENTROPIE, Montpellier, France
| | | | - Mohamad Hassan
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France.,Animal Production Department, Tishreen University, Latakia, Syria
| | - Amandine D Marie
- ARBRE, Agence de Recherche pour la Biodiversité à la Réunion, Saint-Gilles, France
| | | | - Peter Grewe
- CSIRO Environment, Hobart, Tasmania, Australia
| | | | | | | | | | - François Poisson
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France
| | - Denham Parker
- Department of Forestry, Fisheries and the Environment, (DFFE), Cape Town, South Africa.,Department of Biological Sciences, University of Cape Town, Rondebosch, South Africa
| | - Agostino Leone
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France
| | | | | | - Francis Marsac
- UMR MARBEC, University of Montpellier, IRD, Ifremer, CNRS, Sète, France
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8
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Investigating an Unknown Biodiversity: Evidence of Distinct Lineages of the Endemic Chola Guitarfish Pseudobatos percellens Walbaum, 1792 in the Western Atlantic Ocean. DIVERSITY 2023. [DOI: 10.3390/d15030344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/05/2023]
Abstract
Anthropogenic actions have affected marine species for a long time, through overexploitation of natural stocks and habitat degradation, influencing the life strategies of several taxa, especially rays and sharks, which have suffered significant population declines in recent years. Therefore, conservation actions and stock management have become paramount. In this regard, chola guitarfish, Pseudobatos percellens, distributed throughout the Brazilian coast, is often commercially fished by local artisanal fleets or as by-catch in shrimp trawl fisheries. Therefore, this study aimed to understand the genetic diversity of P. percellens throughout the Brazilian coast, using single nucleotide polymorphisms (SNPs). Genetic analyses employing 3329 SNPs revealed a hidden biodiversity within P. percellens, with at least one lineage occurring in the Northern and Northeastern regions and another distributed in the Southeastern/Southern Brazilian coast, with high genetic differentiation between them. However, the Discriminant Analysis of Principal Components (DAPC) indicated the presence of in fact three lineages distributed in these regions that must still be better investigated. Therefore, to ensure adequate conservation of chola guitarfish biodiversity, populations must be managed separately along the Brazilian coast. Furthermore, the need for a taxonomic review for this group is noted.
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9
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Population structure and genetic connectivity of the scalloped hammerhead shark (Sphyrna lewini) across nursery grounds from the Eastern Tropical Pacific: Implications for management and conservation. PLoS One 2022; 17:e0264879. [PMID: 36525407 PMCID: PMC9757582 DOI: 10.1371/journal.pone.0264879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 08/18/2022] [Indexed: 12/23/2022] Open
Abstract
Defining demographically independent units and understanding patterns of gene flow between them is essential for managing and conserving exploited populations. The critically endangered scalloped hammerhead shark, Sphyrna lewini, is a coastal semi-oceanic species found worldwide in tropical and subtropical waters. Pregnant females give birth in shallow coastal estuarine habitats that serve as nursery grounds for neonates and small juveniles, whereas adults move offshore and become highly migratory. We evaluated the population structure and connectivity of S. lewini in coastal areas and one oceanic island (Cocos Island) across the Eastern Tropical Pacific (ETP) using both sequences of the mitochondrial DNA control region (mtCR) and 9 nuclear-encoded microsatellite loci. The mtCR defined two genetically discrete groups: one in the Mexican Pacific and another one in the central-southern Eastern Tropical Pacific (Guatemala, Costa Rica, Panama, and Colombia). Overall, the mtCR data showed low levels of haplotype diversity ranging from 0.000 to 0.608, while nucleotide diversity ranged from 0.000 to 0.0015. More fine-grade population structure was detected using microsatellite loci where Guatemala, Costa Rica, and Panama differed significantly. Relatedness analysis revealed that individuals within nursery areas were more closely related than expected by chance, suggesting that S. lewini may exhibit reproductive philopatric behaviour within the ETP. Findings of at least two different management units, and evidence of philopatric behaviour call for intensive conservation actions for this highly threatened species in the ETP.
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10
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Canfield SJ, Galván-Magaña F, Bowen BW. Little Sharks in a Big World: Mitochondrial DNA Reveals Small-scale Population Structure in the California Horn Shark (Heterodontus francisci). J Hered 2022; 113:298-310. [PMID: 35438775 DOI: 10.1093/jhered/esac008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 02/22/2022] [Indexed: 11/13/2022] Open
Abstract
The California horn shark (Heterodontus francisci) is a small demersal species distributed from southern California and the Channel Islands to Baja California and the Gulf of California. These nocturnal reef predators maintain small home-ranges as adults, and lay auger-shaped egg cases that become wedged into the substrate. While population trends are not well documented, this species is subject to fishing pressure through portions of its range and has been identified as vulnerable to overexploitation. Here we present a survey of 318 specimens from across the range, using mtDNA control region sequences to provide the first genetic assessment of H. francisci. Overall population structure (ΦST = 0.266, P < 0.001) is consistent with limited dispersal as indicated by life history, with two distinct features. Population structure along the continuous coastline is low, with no discernable breaks from Santa Barbara, CA to Bahia Tortugas (Baja California Sur, Mexico); however, there is a notable partition at Punta Eugenia (BCS), a well-known biogeographic break between tropical and subtropical marine faunas. In contrast, population structure is much higher (max ΦST = 0.601, P < 0.05) between the coast and adjacent Channel Islands, a minimum distance of 19 km, indicating that horn sharks rarely disperse across deep habitat and open water. Population structure in most elasmobranchs is measured on a scale of hundreds to thousands of kilometers, but the California Horn Shark has population partitions on an unprecedented small scale, indicating a need for localized management strategies which ensure adequate protection of distinct stocks.
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Affiliation(s)
- Sean J Canfield
- School of Life Sciences, University of Hawai'i at Mānoa, Honolulu, HI, USA.,Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI, USA
| | - Felipe Galván-Magaña
- Instituto Politécnico Nacional, Centro Interdisciplinario de Ciencias Marinas, La Paz, Baja California Sur, México
| | - Brian W Bowen
- Hawai'i Institute of Marine Biology, University of Hawai'i at Mānoa, Kaneohe, HI, USA
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11
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Bernard AM, Finnegan KA, Pavinski Bitar P, Stanhope MJ, Shivji MS. Genomic assessment of global population structure in a highly migratory and habitat versatile apex predator, the tiger shark (Galeocerdo cuvier). J Hered 2021; 112:497-507. [PMID: 34374783 DOI: 10.1093/jhered/esab046] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 08/09/2021] [Indexed: 11/12/2022] Open
Abstract
Understanding the population dynamics of highly mobile, widely distributed, oceanic sharks, many of which are overexploited, is necessary to aid their conservation management. We investigated the global population genomics of tiger sharks (Galeocerdo cuvier), a circumglobally distributed, apex predator displaying remarkable behavioral versatility in its diet, habitat use (near coastal, coral reef, pelagic), and individual movement patterns (spatially resident to long-distance migrations). We genotyped 242 tiger sharks from 10 globally distributed locations at more than 2000 single nucleotide polymorphisms. Although this species often conducts massive distance migrations, the data show strong genetic differentiation at both neutral (FST=0.125-0.144) and candidate outlier loci (FST=0.570-0.761) between western Atlantic and Indo-Pacific sharks, suggesting the potential for adaptation to the environments specific to these oceanic regions. Within these regions, there was mixed support for population differentiation between northern and southern hemispheres in the western Atlantic, and none for structure within the Indian Ocean. Notably, the results demonstrate a low level of population differentiation of tiger sharks from the remote Hawaiian archipelago compared to sharks from the Indian Ocean (FST=0.003-0.005, P<0.01). Given concerns about biodiversity loss and marine ecosystem impacts caused by overfishing of oceanic sharks in the midst of rapid environmental change, our results suggest it imperative that international fishery management prioritize conservation of the evolutionary potential of the highly genetically differentiated Atlantic and Indo-Pacific populations of this unique apex predator. Furthermore, we suggest targeted management attention to tiger sharks in the Hawaiian archipelago based on a precautionary biodiversity conservation perspective.
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Affiliation(s)
- Andrea M Bernard
- Save Our Seas Foundation Shark Research Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA
| | - Kimberly A Finnegan
- Save Our Seas Foundation Shark Research Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA.,Guy Harvey Research Institute, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA
| | - Paulina Pavinski Bitar
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, USA
| | - Mahmood S Shivji
- Save Our Seas Foundation Shark Research Center, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA.,Guy Harvey Research Institute, Nova Southeastern University, 8000 North Ocean Drive, Dania Beach, Florida, USA
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12
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Vaux F, Bohn S, Hyde JR, O'Malley KG. Adaptive markers distinguish North and South Pacific Albacore amid low population differentiation. Evol Appl 2021; 14:1343-1364. [PMID: 34025772 PMCID: PMC8127716 DOI: 10.1111/eva.13202] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/19/2022] Open
Abstract
Albacore (Thunnus alalunga) support an economically valuable global fishery, but surprisingly little is known about the population structure of this highly migratory species. Physical tagging data suggest that Albacore from the North and South Pacific Ocean are separate stocks, but results from previous genetic studies did not support this two stock hypothesis. In addition, observed biological differences among juveniles suggest that there may be population substructure in the North Pacific. We used double-digest restriction site-associated DNA sequencing to assess population structure among 308 Albacore caught in 12 sample areas across the Pacific Ocean (10 North, 2 South). Since Albacore are highly migratory and spawning areas are unknown, sample groups were not assumed to be equivalent to populations and the genetic data were analyzed iteratively. We tested for putatively adaptive differences among groups and for genetic variation associated with sex. Results indicated that Albacore in the North and South Pacific can be distinguished using 84 putatively adaptive loci, but not using the remaining 12,788 presumed neutral sites. However, two individuals likely represent F1 hybrids between the North and South Pacific populations, and 43 Albacore potentially exhibit lower degrees of mixed ancestry. In addition, four or five cross-hemisphere migrants were potentially identified. No genetic evidence was found for population substructure within the North Pacific, and no loci appeared to distinguish males from females. Potential functions for the putatively adaptive loci were identified, but an annotated Albacore genome is required for further exploration. Future research should try to locate spawning areas so that life history, demography, and genetic population structure can be linked and spatiotemporal patterns can be investigated.
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Affiliation(s)
- Felix Vaux
- State Fisheries Genomics LabCoastal Oregon Marine Experiment StationDepartment of Fisheries and WildlifeHatfield Marine Science CenterOregon State UniversityNewportORUSA
- Department of ZoologyUniversity of OtagoDunedinNew Zealand
| | - Sandra Bohn
- State Fisheries Genomics LabCoastal Oregon Marine Experiment StationDepartment of Fisheries and WildlifeHatfield Marine Science CenterOregon State UniversityNewportORUSA
| | - John R. Hyde
- Southwest Fisheries Science CenterNational Marine Fisheries ServiceLa JollaCAUSA
| | - Kathleen G. O'Malley
- State Fisheries Genomics LabCoastal Oregon Marine Experiment StationDepartment of Fisheries and WildlifeHatfield Marine Science CenterOregon State UniversityNewportORUSA
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13
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Kraft DW, Conklin EE, Barba EW, Hutchinson M, Toonen RJ, Forsman ZH, Bowen BW. Genomics versus mtDNA for resolving stock structure in the silky shark ( Carcharhinus falciformis). PeerJ 2020; 8:e10186. [PMID: 33150082 PMCID: PMC7585369 DOI: 10.7717/peerj.10186] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022] Open
Abstract
Conservation genetic approaches for elasmobranchs have focused on regions of the mitochondrial genome or a handful of nuclear microsatellites. High-throughput sequencing offers a powerful alternative for examining population structure using many loci distributed across the nuclear and mitochondrial genomes. These single nucleotide polymorphisms are expected to provide finer scale and more accurate population level data; however, there have been few genomic studies applied to elasmobranch species. The desire to apply next-generation sequencing approaches is often tempered by the costs, which can be offset by pooling specimens prior to sequencing (pool-seq). In this study, we assess the utility of pool-seq by applying this method to the same individual silky sharks, Carcharhinus falciformis, previously surveyed with the mtDNA control region in the Atlantic and Indian Oceans. Pool-seq methods were able to recover the entire mitochondrial genome as well as thousands of nuclear markers. This volume of sequence data enabled the detection of population structure between regions of the Atlantic Ocean populations, undetected in the previous study (inter-Atlantic mitochondrial SNPs FST values comparison ranging from 0.029 to 0.135 and nuclear SNPs from 0.015 to 0.025). Our results reinforce the conclusion that sampling the mitochondrial control region alone may fail to detect fine-scale population structure, and additional sampling across the genome may increase resolution for some species. Additionally, this study shows that the costs of analyzing 4,988 loci using pool-seq methods are equivalent to the standard Sanger-sequenced markers and become less expensive when large numbers of individuals (>300) are analyzed.
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Affiliation(s)
- Derek W. Kraft
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
| | - Emily E. Conklin
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
| | - Evan W. Barba
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
| | - Melanie Hutchinson
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
- Joint Institute of Marine and Atmospheric Research, Pacific Islands Fisheries Science Center, NOAA, University of Hawai’i, Honolulu, HI, USA
| | - Robert J. Toonen
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
| | - Zac H. Forsman
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
| | - Brian W. Bowen
- Hawai’i Institute of Marine Biology, University of Hawai’i, Kaneohe, HI, USA
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14
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Filling the Gap and Improving Conservation: How IUCN Red Lists and Historical Scientific Data Can Shed More Light on Threatened Sharks in the Italian Seas. DIVERSITY 2020. [DOI: 10.3390/d12100389] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Chondrichthyans are one of the most threatened marine taxa worldwide. This is also the case in the Mediterranean Sea, which is considered an extinction hotspot for rays and sharks. The central position of the Italian peninsula makes it an ideal location for studying the status and changes of this sea. There is a lack of biological, ecological and historical data when assessing shark populations, which is also highlighted in the Red List of Threatened Species compiled by the International Union for the Conservation of Nature (IUCN). Historical data can provide important information to better understand how chondrichthyan populations have changed over time. This study aims to provide a clearer understanding of the changes in distribution and abundance of eight shark species in the Italian seas that are currently classified as at risk of extinction by the IUCN. In this respect, a bibliographic review was conducted on items from the 19th century to the first half of the 20th century, focusing on the selected species. The results show that all sharks were considered common until the beginning of the 20th century but have declined since, with a clear negative trend, mainly in the past 70 years. The strong local decline has been attributed to overexploitation, bycatch, habitat loss, depletion of prey items and environmental pollution. Furthermore, historical data also allow us to avoid the issue of a ‘shifting baseline’, in which contemporary abundances are assumed to be “normal”. Using historical data to further our knowledge of the marine environment is becoming increasingly common, and is fundamental in understanding human impact and evaluating mitigation measures to manage and conserve marine species and environments.
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15
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Andrews KR, Copus JM, Wilcox C, Williams AJ, Newman SJ, Wakefield CB, Bowen BW. Range-Wide Population Structure of 3 Deepwater Eteline Snappers Across the Indo-Pacific Basin. J Hered 2020; 111:471-485. [PMID: 32803261 DOI: 10.1093/jhered/esaa029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 08/11/2020] [Indexed: 11/14/2022] Open
Abstract
Deep-sea habitats may drive unique dispersal and demographic patterns for fishes, but population genetic analyses to address these questions have rarely been conducted for fishes in these environments. This study investigates the population structure of 3 tropical deepwater snappers of the genus Etelis that reside at 100-400 m depth, with broad and overlapping distributions in the Indo-Pacific. Previous studies showed little population structure within the Hawaiian Archipelago for 2 of these species: Etelis coruscans and E. carbunculus. Here we extend sampling to the entire geographic range of each species to resolve the population genetic architecture for these 2 species, as well as a recently exposed cryptic species (Etelis sp.). One goal was to determine whether deepwater snappers are more dispersive than shallow-water fishes. A second goal was to determine whether submesophotic fishes have older, more stable populations than shallow reef denizens that are subject to glacial sea-level fluctuations. Both goals are pertinent to the management of these valuable food fishes. A total of 1153 specimens of E. coruscans from 15 geographic regions were analyzed, along with 1064 specimens of E. carbunculus from 11 regions, and 590 specimens of E. sp. from 16 regions. The first 2 species were analyzed with mtDNA and 9-11 microsatellite loci, while E. sp. was analyzed with mtDNA only. Etelis coruscans had a non-significant microsatellite global FST, but significant global mtDNA Ф ST = 0.010 (P = 0.0007), with the isolation of Seychelles in the western Indian Ocean, and intermittent signals of isolation for the Hawaiian Archipelago. Etelis carbunculus had a non-significant microsatellite global FST, and significant global mtDNA Ф ST = 0.021 (P = 0.0001), with low but significant levels of isolation for Hawai'i, and divergence between Tonga and Fiji. Etelis sp. had mtDNA Ф ST = 0.018 (P = 0.0005), with a strong pattern of isolation for both Seychelles and Tonga. Overall, we observed low population structure, shallow mtDNA coalescence (similar to near-shore species), and isolation at the fringes of the Indo-Pacific basin in Hawai'i and the western Indian Ocean. While most shallow-water species have population structure on the scale of biogeographic provinces, deepwater snapper populations are structured on the wider scale of ocean basins, more similar to pelagic fishes than to shallow-water species. This population structure indicates the capacity for widespread dispersal throughout the Indo-Pacific region.
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Affiliation(s)
- Kimberly R Andrews
- Institute for Bioinformatics and Evolutionary Studies, University of Idaho, Moscow, ID.,Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI
| | - Joshua M Copus
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI
| | - Christie Wilcox
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI
| | - Ashley J Williams
- Oceanic Fisheries Programme, The Pacific Community, Noumea, New Caledonia.,Centre for Sustainable Tropical Fisheries and Aquaculture, College of Marine and Environmental Sciences, James Cook University, Townsville, Queensland, Australia
| | - Stephen J Newman
- Western Australian Fisheries and Marine Research Laboratories, Department of Primary Industries and Regional Development, Government of Western Australia, North Beach, WA, Australia
| | - Corey B Wakefield
- Western Australian Fisheries and Marine Research Laboratories, Department of Primary Industries and Regional Development, Government of Western Australia, North Beach, WA, Australia
| | - Brian W Bowen
- Hawai'i Institute of Marine Biology, University of Hawai'i, Kaneohe, HI
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16
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Francisco SM, Robalo JI. Time matters: genetic composition and evaluation of effective population size in temperate coastal fish species. PeerJ 2020; 8:e9098. [PMID: 32391212 PMCID: PMC7197400 DOI: 10.7717/peerj.9098] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 04/09/2020] [Indexed: 12/16/2022] Open
Abstract
Background Extensive knowledge on the genetic characterization of marine organisms has been assembled, mainly concerning the spatial distribution and structuring of populations. Temporal monitoring assesses not only the stability in genetic composition but also its trajectory over time, providing critical information for the accurate forecast of changes in genetic diversity of marine populations, particularly important for both fisheries and endangered species management. We assessed fluctuations in genetic composition among different sampling periods in the western Portuguese shore in three fish species. Methods White seabream Diplodus sargus, sand smelt Atherina presbyter and shanny Lipophrys pholis were chosen, because of their genetic patterns in distinct ecological environments, insight into historical and contemporary factors influencing population effective size (Ne), and degree of commercial exploitation. Samples were obtained near Lisbon between 2003 and 2014 and screened for genetic variation with mitochondrial and nuclear markers. Analyses included genealogies, genetic diversities, temporal structures and contemporary Ne. Results For mtDNA no temporal structure was detected, while for nDNA significant differences were recorded between some sampling periods for the shanny and the sand smelt. Haplotype networks revealed deep genealogies, with various levels of diversification. The shanny revealed a smaller Ne/generation when compared to the other species, which, in turn, revealed no evidence of genetic drift for most study periods. These results highlight the fact that temporal variations in genetic pool composition should be considered when evaluating the population structure of fish species with long distance dispersal, which are more vulnerable to recruitment fluctuations.
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Affiliation(s)
- Sara M Francisco
- MARE-Marine and Environmental Sciences Centre, ISPA-Instituto Universitário, Lisbon, Portugal
| | - Joana I Robalo
- MARE-Marine and Environmental Sciences Centre, ISPA-Instituto Universitário, Lisbon, Portugal
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17
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Johnston EM, Mayo PA, Mensink PJ, Savetsky E, Houghton JDR. Serendipitous re-sighting of a basking shark Cetorhinus maximus reveals inter-annual connectivity between American and European coastal hotspots. JOURNAL OF FISH BIOLOGY 2019; 95:1530-1534. [PMID: 31621067 DOI: 10.1111/jfb.14163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2019] [Accepted: 10/15/2019] [Indexed: 06/10/2023]
Abstract
Transatlantic stock mixing in basking sharks Cetorhinus maximus is supported by low genetic diversity in populations throughout the Atlantic Ocean. However, despite significant focus on the species' movements; >1500 individual sharks marked for recapture and >150 individuals equipped with remote tracking tags, only a single record of transatlantic movment has been previously recorded. Within this context, the seredipitous re-sighting of a female basking shark fitted with a satellite transmitter at Malin Head, Ireland 993 days later at Cape Cod, USA is noteworthy.
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Affiliation(s)
- Emmett M Johnston
- School of Biological Sciences, Queen's University Belfast, Northern Ireland, UK
- Irish Basking Shark Study Group, County Donegal, Ireland
- Department of Culture, Heritage and Gaeltacht, National Parks and Wildlife Service, Dublin, Ireland
| | - Paul A Mayo
- School of Biological Sciences, Queen's University Belfast, Northern Ireland, UK
- Irish Basking Shark Study Group, County Donegal, Ireland
| | - Paul J Mensink
- School of Biological Sciences, Queen's University Belfast, Northern Ireland, UK
- Queen's University Marine Laboratory, Northern Ireland, UK
- Department of Biology, Biological & Geological Sciences Building, Western University, London, Canada
| | - Eric Savetsky
- Eric Savetsky Photography, Nantucket, Massachusetts, USA
| | - Jonathan D R Houghton
- School of Biological Sciences, Queen's University Belfast, Northern Ireland, UK
- Irish Basking Shark Study Group, County Donegal, Ireland
- Queen's University Marine Laboratory, Northern Ireland, UK
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18
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Bitencourt A, Silva D, Carvalho E, Loiola S, Amaral C. Study of genetic variability of the Blue Shark Prionace glauca (Linnaeus, 1758). FORENSIC SCIENCE INTERNATIONAL GENETICS SUPPLEMENT SERIES 2019. [DOI: 10.1016/j.fsigss.2019.10.103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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19
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Bernard AM, Richards VP, Stanhope MJ, Shivji MS. Transcriptome-Derived Microsatellites Demonstrate Strong Genetic Differentiation in Pacific White Sharks. J Hered 2019; 109:771-779. [PMID: 30204894 DOI: 10.1093/jhered/esy045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 09/08/2018] [Indexed: 01/25/2023] Open
Abstract
Recent advances in genome-scale sequencing technology have allowed the development of high resolution genetic markers for the study of nonmodel taxa. In particular, transcriptome sequencing has proven to be highly useful in generating genomic markers for use in population genetic studies, allowing for insight into species connectivity, as well as local adaptive processes as many transcriptome-derived markers are found within or associated with functional genes. Herein, we developed a set of 30 microsatellite markers from a heart transcriptome for the white shark (Carcharodon carcharias), a widely distributed and globally vulnerable marine predator. Using these markers as well as 10 published anonymous genomic microsatellite loci, we provide 1) the first nuclear genetic assessment of the cross-Pacific connectivity of white sharks, and 2) a comparison of the levels of inferred differentiation across microsatellite marker sets (i.e., transcriptome vs. anonymous) to assess their respective utility to elucidate the population genetic dynamics of white sharks. Significant (FST = 0.083, P = 0.05; G″ST = 0.200; P = 0.001) genetic differentiation was found between Southwestern Pacific (n = 19) and Northeastern Pacific (n = 20) white sharks, indicating restricted, cross Pacific gene flow in this species. Transcriptome-derived microsatellite marker sets identified much higher (up to 2×) levels of genetic differentiation than anonymous genomic markers, underscoring potential utility of transcriptome markers in identifying subtle population genetic differences within highly vagile, globally distributed marine species.Subject areas: Population structure and phylogeography; Conservation genetics and biodiversity.
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Affiliation(s)
- Andrea M Bernard
- Save Our Seas Shark Research Center & Guy Harvey Research Institute, Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, North Ocean Drive, Dania Beach, FL
| | - Vincent P Richards
- Department of Biological Sciences, College of Science, Clemson University, Clemson, SC
| | - Michael J Stanhope
- Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY
| | - Mahmood S Shivji
- Save Our Seas Shark Research Center & Guy Harvey Research Institute, Nova Southeastern University, Halmos College of Natural Sciences and Oceanography, North Ocean Drive, Dania Beach, FL
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20
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Sandoval-Castillo J. Conservation genetics of elasmobranchs of the Mexican Pacific Coast, trends and perspectives. ADVANCES IN MARINE BIOLOGY 2019; 83:115-157. [PMID: 31606069 DOI: 10.1016/bs.amb.2019.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
One of the most critical threats to biodiversity is the high extinction rate driven by human activities. Reducing extinction rates requires the implementation of conservation programmes based on robust scientific data. Elasmobranchs are important ecological components of the ocean, and several species sustain substantial economic activities. Unfortunately, elasmobranchs are one of the most threatened and understudied animal taxa. The Mexican Pacific Coast (MPC) is a region with high elasmobranch diversity and is the seat of major elasmobranch fisheries. But it is also a developing region with several conservation and management challenges which require national and international attention. Here, we review the conservation genetics literature of elasmobranchs from the MPC. We present a synthesis of the works using samples from the region and emphasize the main gaps and biases in these data. In addition, we discuss the benefits and challenges of generating genomic information to improve the management and conservation of an elasmobranch biodiversity hotspot in a developing country. We found 47 elasmobranch genetic articles that cover <30% of the elasmobranch diversity in the region. These studies mainly used mitochondrial DNA sequences to analyse the genetic structure of commercially important and abundant species of the order Carcharhiniformes. Some of these papers also assessed mating systems, demographic parameters, and taxonomic uncertainties, all of which are important topics for efficient management decisions. In terms of conservation genetics, elasmobranchs from the MPC remain understudied. However, high-throughput sequencing technologies have increased the power and accessibility of genomic tools, even in developing countries such as Mexico. The tools described here provide information relevant for biodiversity conservation. Therefore, we strongly suggest that investment in genomic research will assist implementation of efficient management strategies. In time, this will reduce the extinction risk of the unique elasmobranch biodiversity from the MPC.
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Affiliation(s)
- Jonathan Sandoval-Castillo
- Molecular Ecology Lab, College of Science and Engineering, Flinders University, Adelaide, SA, Australia.
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21
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Sukumaran S, Sebastian W, Francis KX, Gopalakrishnan A. Contemporary and historic patterns of intraspecific diversity in Indian anchovy, Stolephorus indicus, from Indian peninsular waters. Genetica 2019; 147:259-267. [PMID: 31144087 DOI: 10.1007/s10709-019-00068-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Accepted: 05/25/2019] [Indexed: 10/26/2022]
Abstract
We analyzed intraspecific diversity of Indian anchovy, Stolephorus indicus, a commercially and ecologically important species, using mitochondrial DNA markers so as to derive insights into population structuring and historical demography. Analyses were carried out on 128 and 138 individuals collected from 5 locations along the range of distribution using mitochondrial ATPase (843 bp) and COI (663 bp) sequences respectively. Significant connectivity and gene flow was detected among fishes collected from all the geographic locations as indicated by lack of structuring in Bayesian clustering analysis along with insignificant ΦST values. Oceanographic features of the Bay of Bengal, Arabian Sea and Andaman Sea may be favorable for the dispersal of anchovy larvae and subsequent gene flow. Historical demographic analyses indicated a demographic and spatial expansion taken place approximately during 125,000 years before present, the Pleistocene epoch. Indian Ocean witnessed emergence of upwelling events and consequent increase in productivity during the Pleistocene epoch causing a demographic and spatial expansion of anchovies. Management measures for this species should be devised considering it as a single stock along its entire range of distribution.
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Affiliation(s)
- Sandhya Sukumaran
- ICAR-Central Marine Fisheries Research Institute, Post Box No 1603, Ernakulam North P.O., Kochi, Kerala, 682018, India.
| | - Wilson Sebastian
- ICAR-Central Marine Fisheries Research Institute, Post Box No 1603, Ernakulam North P.O., Kochi, Kerala, 682018, India
| | - K X Francis
- ICAR-Central Marine Fisheries Research Institute, Post Box No 1603, Ernakulam North P.O., Kochi, Kerala, 682018, India
| | - A Gopalakrishnan
- ICAR-Central Marine Fisheries Research Institute, Post Box No 1603, Ernakulam North P.O., Kochi, Kerala, 682018, India
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22
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Pirog A, Jaquemet S, Ravigné V, Cliff G, Clua E, Holmes BJ, Hussey NE, Nevill JEG, Temple AJ, Berggren P, Vigliola L, Magalon H. Genetic population structure and demography of an apex predator, the tiger shark Galeocerdo cuvier. Ecol Evol 2019; 9:5551-5571. [PMID: 31160982 PMCID: PMC6540675 DOI: 10.1002/ece3.5111] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 01/20/2019] [Accepted: 02/26/2019] [Indexed: 12/16/2022] Open
Abstract
Population genetics has been increasingly applied to study large sharks over the last decade. Whilst large shark species are often difficult to study with direct methods, improved knowledge is needed for both population management and conservation, especially for species vulnerable to anthropogenic and climatic impacts. The tiger shark, Galeocerdo cuvier, is an apex predator known to play important direct and indirect roles in tropical and subtropical marine ecosystems. While the global and Indo-West Pacific population genetic structure of this species has recently been investigated, questions remain over population structure and demographic history within the western Indian (WIO) and within the western Pacific Oceans (WPO). To address the knowledge gap in tiger shark regional population structures, the genetic diversity of 286 individuals sampled in seven localities was investigated using 27 microsatellite loci and three mitochondrial genes (CR,COI, and cytb). A weak genetic differentiation was observed between the WIO and the WPO, suggesting high genetic connectivity. This result agrees with previous studies and highlights the importance of the pelagic behavior of this species to ensure gene flow. Using approximate Bayesian computation to couple information from both nuclear and mitochondrial markers, evidence of a recent bottleneck in the Holocene (2,000-3,000 years ago) was found, which is the most probable cause for the low genetic diversity observed. A contemporary effective population size as low as 111 [43,369] was estimated during the bottleneck. Together, these results indicate low genetic diversity that may reflect a vulnerable population sensitive to regional pressures. Conservation measures are thus needed to protect a species that is classified as Near Threatened.
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Affiliation(s)
- Agathe Pirog
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Université de La RéunionSaint Denis, La RéunionFrance
| | - Sébastien Jaquemet
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Université de La RéunionSaint Denis, La RéunionFrance
| | | | - Geremy Cliff
- KwaZulu‐Natal Sharks BoardUmhlanga RocksSouth Africa
- School of Life SciencesUniversity of KwaZulu‐NatalDurbanSouth Africa
| | - Eric Clua
- EPHE‐CNRS‐UPVDCNRS UPVDUSR 3278 CRIOBEPSL Research UniversityPerpignanFrance
- Laboratoire d'Excellence CORAILPerpignanFrance
| | - Bonnie J. Holmes
- School of Biological SciencesUniversity of Queensland, St LuciaBrisbaneQueenslandAustralia
| | - Nigel E. Hussey
- Biological SciencesUniversity of WindsorWindsorOntarioCanada
| | | | - Andrew J. Temple
- School of Natural and Environmental SciencesNewcastle UniversityNewcastle‐upon‐TyneUK
| | - Per Berggren
- School of Natural and Environmental SciencesNewcastle UniversityNewcastle‐upon‐TyneUK
| | - Laurent Vigliola
- Laboratoire d'Excellence CORAILPerpignanFrance
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Institut de Recherche pour le DéveloppementNouméaNouvelle CalédonieFrance
| | - Hélène Magalon
- UMR ENTROPIE (Université de La Réunion/IRD/CNRS)Université de La RéunionSaint Denis, La RéunionFrance
- Laboratoire d'Excellence CORAILPerpignanFrance
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23
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Bailleul D, Mackenzie A, Sacchi O, Poisson F, Bierne N, Arnaud‐Haond S. Large-scale genetic panmixia in the blue shark ( Prionace glauca): A single worldwide population, or a genetic lag-time effect of the "grey zone" of differentiation? Evol Appl 2018; 11:614-630. [PMID: 29875806 PMCID: PMC5978958 DOI: 10.1111/eva.12591] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 12/12/2017] [Indexed: 12/31/2022] Open
Abstract
The blue shark Prionace glauca, among the most common and widely studied pelagic sharks, is a top predator, exhibiting the widest distribution range. However, little is known about its population structure and spatial dynamics. With an estimated removal of 10-20 million individuals per year by fisheries, the species is classified as "Near Threatened" by International Union for Conservation of Nature. We lack the knowledge to forecast the long-term consequences of such a huge removal on this top predator itself and on its trophic network. The genetic analysis of more than 200 samples collected at broad scale (from Mediterranean Sea, North Atlantic and Pacific Oceans) using mtDNA and nine microsatellite markers allowed to detect signatures of genetic bottlenecks but a nearly complete genetic homogeneity across the entire studied range. This apparent panmixia could be explained by a genetic lag-time effect illustrated by simulations of demographic changes that were not detectable through standard genetic analysis before a long transitional phase here introduced as the "population grey zone." The results presented here can thus encompass distinct explanatory scenarios spanning from a single demographic population to several independent populations. This limitation prevents the genetic-based delineation of stocks and thus the ability to anticipate the consequences of severe depletions at all scales. More information is required for the conservation of population(s) and management of stocks, which may be provided by large-scale sampling not only of individuals worldwide, but also of loci genomewide.
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Affiliation(s)
- Diane Bailleul
- IFREMER, UMR MARBEC, Station de SèteSèteFrance
- OREME – Station MarineUniversité MontpellierSèteFrance
| | - Alicia Mackenzie
- IFREMER, UMR MARBEC, Station de SèteSèteFrance
- OREME – Station MarineUniversité MontpellierSèteFrance
| | - Olivier Sacchi
- IFREMER, UMR MARBEC, Station de SèteSèteFrance
- OREME – Station MarineUniversité MontpellierSèteFrance
| | | | - Nicolas Bierne
- OREME – Station MarineUniversité MontpellierSèteFrance
- CNRS, Institut des Sciences de l'EvolutionUniversité MontpellierMontpellierFrance
| | - Sophie Arnaud‐Haond
- IFREMER, UMR MARBEC, Station de SèteSèteFrance
- OREME – Station MarineUniversité MontpellierSèteFrance
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Incorporating non-equilibrium dynamics into demographic history inferences of a migratory marine species. Heredity (Edinb) 2018; 122:53-68. [PMID: 29720718 DOI: 10.1038/s41437-018-0077-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 03/08/2018] [Accepted: 03/17/2018] [Indexed: 01/26/2023] Open
Abstract
Understanding how dispersal and gene flow link geographically separated the populations over evolutionary history is challenging, particularly in migratory marine species. In southern right whales (SRWs, Eubalaena australis), patterns of genetic diversity are likely influenced by the glacial climate cycle and recent history of whaling. Here we use a dataset of mitochondrial DNA (mtDNA) sequences (n = 1327) and nuclear markers (17 microsatellite loci, n = 222) from major wintering grounds to investigate circumpolar population structure, historical demography and effective population size. Analyses of nuclear genetic variation identify two population clusters that correspond to the South Atlantic and Indo-Pacific ocean basins that have similar effective breeder estimates. In contrast, all wintering grounds show significant differentiation for mtDNA, but no sex-biased dispersal was detected using the microsatellite genotypes. An approximate Bayesian computation (ABC) approach with microsatellite markers compared the scenarios with gene flow through time, or isolation and secondary contact between ocean basins, while modelling declines in abundance linked to whaling. Secondary-contact scenarios yield the highest posterior probabilities, implying that populations in different ocean basins were largely isolated and came into secondary contact within the last 25,000 years, but the role of whaling in changes in genetic diversity and gene flow over recent generations could not be resolved. We hypothesise that these findings are driven by factors that promote isolation, such as female philopatry, and factors that could promote dispersal, such as oceanographic changes. These findings highlight the application of ABC approaches to infer the connectivity in mobile species with complex population histories and, currently, low levels of differentiation.
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Liu SYV, Joung SJ, Yu CJ, Hsu HH, Tsai WP, Liu KM. Genetic diversity and connectivity of the megamouth shark ( Megachasma pelagios). PeerJ 2018. [PMID: 29527411 PMCID: PMC5842762 DOI: 10.7717/peerj.4432] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The megamouth shark (Megachasma pelagios) was described as a new species in 1983. Since then, only ca. 100 individuals have been observed or caught. Its horizontal migration, dispersal, and connectivity patterns are still unknown due to its rarity. Two genetic markers were used in this study to reveal its genetic diversity and connectivity pattern. This approach provides a proxy to indirectly measure gene flow between populations. Tissues from 27 megamouth sharks caught by drift nets off the Hualien coast (eastern Taiwan) were collected from 2013 to 2015. With two additional tissue samples from megamouths caught in Baja California, Mexico, and sequences obtained from GenBank, we were able to perform the first population genetic analyses of the megamouth shark. The mtDNA cox1 gene and a microsatellite (Loc 6) were sequenced and analyzed. Our results showed that there is no genetic structure in the megamouth shark, suggesting a possible panmictic population. Based on occurrence data, we also suggest that the Kuroshio region, including the Philippines, Taiwan, and Japan, may act as a passageway for megamouth sharks to reach their feeding grounds from April to August. Our results provide insights into the dispersal and connectivity of megamouth sharks. Future studies should focus on collecting more samples and conducting satellite tagging to better understand the global migration and connectivity pattern of the megamouth shark.
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Affiliation(s)
- Shang Yin Vanson Liu
- Department of Marine Biotechnology and Resources, National Sun Yat-Sen University, Kaohsiung, Taiwan.,Doctoral Degree Program in Marine Biotechnology, National Sun Yat-Sen University, Taiwan
| | - Shoou Jeng Joung
- Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Taiwan.,George Chen Shark Research Center, National Taiwan Ocean University, Taiwan
| | - Chi-Ju Yu
- Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Taiwan
| | - Hua-Hsun Hsu
- Department of Environmental Biology and Fisheries Science, National Taiwan Ocean University, Taiwan.,George Chen Shark Research Center, National Taiwan Ocean University, Taiwan.,Center for Environment and Water, Research Institute, King Fahad University of Petroleum and Minerals, Saudi Arabia
| | - Wen-Pei Tsai
- Department of Fisheries Production and Management, National Kaohsiung Marine University, Kaohsiung
| | - Kwang Ming Liu
- George Chen Shark Research Center, National Taiwan Ocean University, Taiwan.,Institute of Marine Affairs and Resource Management, National Taiwan Ocean University, Taiwan
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27
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Leone A, Urso I, Damalas D, Martinsohn J, Zanzi A, Mariani S, Sperone E, Micarelli P, Garibaldi F, Megalofonou P, Bargelloni L, Franch R, Macias D, Prodöhl P, Fitzpatrick S, Stagioni M, Tinti F, Cariani A. Genetic differentiation and phylogeography of Mediterranean-North Eastern Atlantic blue shark ( Prionace glauca, L. 1758) using mitochondrial DNA: panmixia or complex stock structure? PeerJ 2017; 5:e4112. [PMID: 29230359 PMCID: PMC5723133 DOI: 10.7717/peerj.4112] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Accepted: 11/09/2017] [Indexed: 11/25/2022] Open
Abstract
Background The blue shark (Prionace glauca, Linnaeus 1758) is one of the most abundant epipelagic shark inhabiting all the oceans except the poles, including the Mediterranean Sea, but its genetic structure has not been confirmed at basin and interoceanic distances. Past tagging programs in the Atlantic Ocean failed to find evidence of migration of blue sharks between the Mediterranean and the adjacent Atlantic, despite the extreme vagility of the species. Although the high rate of by-catch in the Mediterranean basin, to date no genetic study on Mediterranean blue shark was carried out, which constitutes a significant knowledge gap, considering that this population is classified as “Critically Endangered”, unlike its open-ocean counterpart. Methods Blue shark phylogeography and demography in the Mediterranean Sea and North-Eastern Atlantic Ocean were inferred using two mitochondrial genes (Cytb and control region) amplified from 207 and 170 individuals respectively, collected from six localities across the Mediterranean and two from the North-Eastern Atlantic. Results Although no obvious pattern of geographical differentiation was apparent from the haplotype network, Φst analyses indicated significant genetic structure among four geographical groups. Demographic analyses suggest that these populations have experienced a constant population expansion in the last 0.4–0.1 million of years. Discussion The weak, but significant, differences in Mediterranean and adjacent North-eastern Atlantic blue sharks revealed a complex phylogeographic structure, which appears to reject the assumption of panmixia across the study area, but also supports a certain degree of population connectivity across the Strait of Gibraltar, despite the lack of evidence of migratory movements observed by tagging data. Analyses of spatial genetic structure in relation to sex-ratio and size could indicate some level of sex/stage biased migratory behaviour.
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Affiliation(s)
- Agostino Leone
- Department of Biological, Geological and Environmental Sciences (BiGeA), Laboratory of Genetics & Genomics of Marine Resources and Environment (GenoDREAM), University of Bologna, Ravenna, Italy
| | - Ilenia Urso
- Department of Biological, Geological and Environmental Sciences (BiGeA), Laboratory of Genetics & Genomics of Marine Resources and Environment (GenoDREAM), University of Bologna, Ravenna, Italy
| | - Dimitrios Damalas
- Joint Research Centre (JRC), Directorate D-Sustainable Resources, Unit D2-Water and Marine Resources, European Commission, Ispra, Italy.,Current affiliation: Hellenic Centre for Marine Research, Athinon, Anavyssos, Greece
| | - Jann Martinsohn
- Joint Research Centre (JRC), Directorate D-Sustainable Resources, Unit D2-Water and Marine Resources, European Commission, Ispra, Italy
| | - Antonella Zanzi
- Joint Research Centre (JRC), Directorate D-Sustainable Resources, Unit D2-Water and Marine Resources, European Commission, Ispra, Italy
| | - Stefano Mariani
- School of Environment & Life Sciences, University of Salford, Salford, Greater Manchester, United Kingdom
| | - Emilio Sperone
- Department of Biology, Ecology and Earth Science (DiBEST), University of Calabria, Arcavacata di Rende, Italy
| | - Primo Micarelli
- Sharks Research Center, Aquarium Mondo Marino, Massa Marittima, Italy
| | - Fulvio Garibaldi
- Department of Earth, Environment and Life Sciences, University of Genova, Genova, Italy
| | - Persefoni Megalofonou
- Department of Biology, National and Kapodistrian University of Athens, Ilissia, Greece
| | - Luca Bargelloni
- Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro, Italy
| | - Rafaella Franch
- Department of Comparative Biomedicine and Food Science, University of Padova, Legnaro, Italy
| | - David Macias
- Centro Oceanográfico de Málaga, Instituto Español de Oceanografía, Málaga, Spain
| | - Paulo Prodöhl
- School of Biological Sciences, Queen's University, Institute for Global Food Security, Belfast, United Kingdom
| | - Séan Fitzpatrick
- School of Biological Sciences, Queen's University, Institute for Global Food Security, Belfast, United Kingdom
| | - Marco Stagioni
- Department of Biological, Geological and Environmental Sciences, Marine Biology and Fisheries Laboratory, University of Bologna, Fano, Italy
| | - Fausto Tinti
- Department of Biological, Geological and Environmental Sciences (BiGeA), Laboratory of Genetics & Genomics of Marine Resources and Environment (GenoDREAM), University of Bologna, Ravenna, Italy
| | - Alessia Cariani
- Department of Biological, Geological and Environmental Sciences (BiGeA), Laboratory of Genetics & Genomics of Marine Resources and Environment (GenoDREAM), University of Bologna, Ravenna, Italy
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Veríssimo A, Sampaio Í, McDowell JR, Alexandrino P, Mucientes G, Queiroz N, da Silva C, Jones CS, Noble LR. World without borders-genetic population structure of a highly migratory marine predator, the blue shark ( Prionace glauca). Ecol Evol 2017; 7:4768-4781. [PMID: 28690806 PMCID: PMC5496551 DOI: 10.1002/ece3.2987] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 03/10/2017] [Accepted: 03/21/2017] [Indexed: 01/21/2023] Open
Abstract
Highly migratory, cosmopolitan oceanic sharks often exhibit complex movement patterns influenced by ontogeny, reproduction, and feeding. These elusive species are particularly challenging to population genetic studies, as representative samples suitable for inferring genetic structure are difficult to obtain. Our study provides insights into the genetic population structure one of the most abundant and wide-ranging oceanic shark species, the blue shark Prionace glauca, by sampling the least mobile component of the populations, i.e., young-of-year and small juveniles (<2 year; N = 348 individuals), at three reported nursery areas, namely, western Iberia, Azores, and South Africa. Samples were collected in two different time periods (2002-2008 and 2012-2015) and were screened at 12 nuclear microsatellites and at a 899-bp fragment of the mitochondrial control region. Our results show temporally stable genetic homogeneity among the three Atlantic nurseries at both nuclear and mitochondrial markers, suggesting basin-wide panmixia. In addition, comparison of mtDNA CR sequences from Atlantic and Indo-Pacific locations also indicated genetic homogeneity and unrestricted female-mediated gene flow between ocean basins. These results are discussed in light of the species' life history and ecology, but suggest that blue shark populations may be connected by gene flow at the global scale. The implications of the present findings to the management of this important fisheries resource are also discussed.
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Affiliation(s)
- Ana Veríssimo
- CIBIO – U.P. – Research Center for Biodiversity and Genetic ResourcesVairãoPortugal
- Virginia Institute of Marine ScienceCollege of William and MaryGloucester PointVAUSA
| | - Íris Sampaio
- CIBIO – U.P. – Research Center for Biodiversity and Genetic ResourcesVairãoPortugal
| | - Jan R. McDowell
- Virginia Institute of Marine ScienceCollege of William and MaryGloucester PointVAUSA
| | - Paulo Alexandrino
- CIBIO – U.P. – Research Center for Biodiversity and Genetic ResourcesVairãoPortugal
| | - Gonzalo Mucientes
- CIBIO – U.P. – Research Center for Biodiversity and Genetic ResourcesVairãoPortugal
- Centro Tecnológico del MarFundación CETMARVigoSpain
| | - Nuno Queiroz
- CIBIO – U.P. – Research Center for Biodiversity and Genetic ResourcesVairãoPortugal
| | - Charlene da Silva
- Department of Agriculture, Forestry and FisheriesBranch FisheriesRogge BaySouth Africa
| | - Catherine S. Jones
- Institute of Biological and Environmental SciencesSchool of Biological SciencesUniversity of AberdeenAberdeenUK
| | - Leslie R. Noble
- Institute of Biological and Environmental SciencesSchool of Biological SciencesUniversity of AberdeenAberdeenUK
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