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Bertram A, Bell J, Brauer C, Fairclough D, Hamer P, Sandoval‐Castillo J, Wellenreuther M, Beheregaray LB. Estimation of effective number of breeders and effective population size in an abundant and heavily exploited marine teleost. Evol Appl 2024; 17:e13758. [PMID: 39040813 PMCID: PMC11261160 DOI: 10.1111/eva.13758] [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: 12/18/2023] [Revised: 05/16/2024] [Accepted: 07/03/2024] [Indexed: 07/24/2024] Open
Abstract
Obtaining reliable estimates of the effective number of breeders (N b) and generational effective population size (N e) for fishery-important species is challenging because they are often iteroparous and highly abundant, which can lead to bias and imprecision. However, recent advances in understanding of these parameters, as well as the development of bias correction methods, have improved the capacity to generate reliable estimates. We utilized samples of both single-cohort young of the year and mixed-age adults from two geographically and genetically isolated stocks of the Australasian snapper (Chrysophrys auratus) to investigate the feasibility of generating reliable N b and N e estimates for a fishery species. Snapper is an abundant, iteroparous broadcast spawning teleost that is heavily exploited by recreational and commercial fisheries. Employing neutral genome-wide SNPs and the linkage-disequilibrium method, we determined that the most reliable N b and N e estimates could be derived by genotyping at least 200 individuals from a single cohort. Although our estimates made from the mixed-age adult samples were generally lower and less precise than those based on a single cohort, they still proved useful for understanding relative differences in genetic effective size between stocks. The correction formulas applied to adjust for biases due to physical linkage of loci and age structure resulted in substantial upward modifications of our estimates, demonstrating the importance of applying these bias corrections. Our findings provide important guidelines for estimating N b and N e for iteroparous species with large populations. This work also highlights the utility of samples originally collected for stock structure and stock assessment work for investigating genetic effective size in fishery-important species.
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Affiliation(s)
- Andrea Bertram
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - Justin Bell
- Victorian Fisheries AuthorityQueenscliffVictoriaAustralia
| | - Chris Brauer
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - David Fairclough
- Department of Primary Industries and Regional DevelopmentAquatic Sciences and AssessmentHillarysWestern AustraliaAustralia
| | | | - Jonathan Sandoval‐Castillo
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
| | - Maren Wellenreuther
- The New Zealand Institute for Plant and Food Research LimitedNelsonNew Zealand
- The School of Biological SciencesUniversity of AucklandAucklandNew Zealand
| | - Luciano B. Beheregaray
- Molecular Ecology Laboratory, College of Science and EngineeringFlinders UniversityBedford ParkSouth AustraliaAustralia
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2
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GuibingaMickala A, Weber A, Ntie S, Gahlot P, Lehmann D, Mickala P, Abernethy K, Anthony N. Estimation of the census (Nc) and effective (Ne) population size of a wild mandrill (Mandrillus sphinx) horde in the Lopé National Park, Gabon using a non-invasive genetic approach. CONSERV GENET 2022. [DOI: 10.1007/s10592-022-01458-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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3
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Koot E, Wu C, Ruza I, Hilario E, Storey R, Wells R, Chagné D, Wellenreuther M. Genome-wide analysis reveals the genetic stock structure of hoki ( Macruronus novaezelandiae). Evol Appl 2021; 14:2848-2863. [PMID: 34950233 PMCID: PMC8674887 DOI: 10.1111/eva.13317] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/14/2021] [Accepted: 10/18/2021] [Indexed: 12/23/2022] Open
Abstract
The assessment of the genetic structuring of biodiversity is crucial for management and conservation. This is particularly critical for widely distributed and highly mobile deep-water teleosts, such as hoki (Macruronus novaezelandiae). This species is significant to Māori people and supports the largest commercial fishery in New Zealand, but uncertainty about its stock structure presents a challenge for management. Here, we apply a comprehensive genomic analysis to shed light on the demographic structure of this species by (1) assembling the genome, (2) generating a catalogue of genome-wide SNPs to infer the stock structure and (3) identifying regions of the genome under selection. The final genome assembly used short and long reads and is near complete, representing 93.8% of BUSCO genes, and consisting of 566 contigs totalling 501 Mb. Whole-genome re-sequencing of 510 hoki sampled from 14 locations around New Zealand and Australia, at a read depth greater than 10×, produced 227,490 filtered SNPs. Analyses of these SNPs were able to resolve the stock structure of hoki into two genetically and geographically distinct clusters, one including the Australian and the other one all New Zealand locations, indicating genetic exchange between these regions is limited. Location differences within New Zealand samples were much more subtle (global F ST = 0.0006), and while small and significant differences could be detected, they did not conclusively identify additional substructures. Ten putative adaptive SNPs were detected within the New Zealand samples, but these also did not geographically partition the dataset further. Contemporary and historical N e estimation suggest the current New Zealand population of hoki is large yet declining. Overall, our study provides the first genomic resources for hoki and provides detailed insights into the fine-scale population genetic structure to inform the management of this species.
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Affiliation(s)
- Emily Koot
- The New Zealand Institute for Plant and Food Research LtdPalmerston NorthNew Zealand
| | - Chen Wu
- The New Zealand Institute for Plant and Food Research LtdAucklandNew Zealand
| | - Igor Ruza
- The New Zealand Institute for Plant and Food Research LtdNelsonNew Zealand
| | - Elena Hilario
- The New Zealand Institute for Plant and Food Research LtdAucklandNew Zealand
| | - Roy Storey
- The New Zealand Institute for Plant and Food Research LtdTe PukeNew Zealand
| | | | - David Chagné
- The New Zealand Institute for Plant and Food Research LtdPalmerston NorthNew Zealand
| | - Maren Wellenreuther
- The New Zealand Institute for Plant and Food Research LtdNelsonNew Zealand
- School of Biological SciencesThe University of AucklandAucklandNew Zealand
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4
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Bilgmann K, Armansin N, Ferchaud A, Normandeau E, Bernatchez L, Harcourt R, Ahonen H, Lowther A, Goldsworthy S, Stow A. Low effective population size in the genetically bottlenecked Australian sea lion is insufficient to maintain genetic variation. Anim Conserv 2021. [DOI: 10.1111/acv.12688] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Bilgmann
- Department of Biological Sciences Macquarie University Sydney Australia
| | - N. Armansin
- Department of Biological Sciences Macquarie University Sydney Australia
| | - A.L. Ferchaud
- Département de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec QC Canada
| | - E. Normandeau
- Département de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec QC Canada
| | - L. Bernatchez
- Département de Biologie Institut de Biologie Intégrative et des Systèmes (IBIS) Université Laval Québec QC Canada
| | - R. Harcourt
- Department of Biological Sciences Macquarie University Sydney Australia
| | - H. Ahonen
- Department of Biological Sciences Macquarie University Sydney Australia
- Norwegian Polar Institute Tromsø Norway
| | | | - S.D. Goldsworthy
- South Australian Research and Development Institute Adelaide South Australia
| | - A. Stow
- Department of Biological Sciences Macquarie University Sydney Australia
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5
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Population genetics informs the management of a controversial Australian waterbird. CONSERV GENET 2021. [DOI: 10.1007/s10592-021-01393-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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6
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Stahlke A, Bell D, Dhendup T, Kern B, Pannoni S, Robinson Z, Strait J, Smith S, Hand BK, Hohenlohe PA, Luikart G. Population Genomics Training for the Next Generation of Conservation Geneticists: ConGen 2018 Workshop. J Hered 2021; 111:227-236. [PMID: 32037446 PMCID: PMC7117792 DOI: 10.1093/jhered/esaa001] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 01/06/2020] [Indexed: 12/30/2022] Open
Abstract
The increasing availability and complexity of next-generation sequencing (NGS) data sets make ongoing training an essential component of conservation and population genetics research. A workshop entitled “ConGen 2018” was recently held to train researchers in conceptual and practical aspects of NGS data production and analysis for conservation and ecological applications. Sixteen instructors provided helpful lectures, discussions, and hands-on exercises regarding how to plan, produce, and analyze data for many important research questions. Lecture topics ranged from understanding probabilistic (e.g., Bayesian) genotype calling to the detection of local adaptation signatures from genomic, transcriptomic, and epigenomic data. We report on progress in addressing central questions of conservation genomics, advances in NGS data analysis, the potential for genomic tools to assess adaptive capacity, and strategies for training the next generation of conservation genomicists.
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Affiliation(s)
- Amanda Stahlke
- Institute for Bioinformatics and Evolutionary Studies, University of Idaho, Moscow, ID
| | - Donavan Bell
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT
| | - Tashi Dhendup
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT.,Department of Forest and Park Services, Ugyen Wangchuck Institute for Conservation and Environmental Research, Bumthang, Bhutan
| | - Brooke Kern
- Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT.,Department of Plant and Microbial Biology, University of Minnesota, St. Paul, MN
| | - Samuel Pannoni
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT.,Flathead Lake Biological Station, Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT
| | - Zachary Robinson
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT
| | - Jeffrey Strait
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT
| | - Seth Smith
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT.,Flathead Lake Biological Station, Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT.,Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI
| | - Brian K Hand
- Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT.,Flathead Lake Biological Station, Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT
| | - Paul A Hohenlohe
- Institute for Bioinformatics and Evolutionary Studies, University of Idaho, Moscow, ID
| | - Gordon Luikart
- Wildlife Biology Program, College of Forestry and Conservation, University of Montana, Missoula, MT.,Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT.,Flathead Lake Biological Station, Division of Biological Sciences, College of Humanities and Sciences, University of Montana, Missoula, MT
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Schweizer RM, Saarman N, Ramstad KM, Forester BR, Kelley JL, Hand BK, Malison RL, Ackiss AS, Watsa M, Nelson TC, Beja-Pereira A, Waples RS, Funk WC, Luikart G. Big Data in Conservation Genomics: Boosting Skills, Hedging Bets, and Staying Current in the Field. J Hered 2021; 112:313-327. [PMID: 33860294 DOI: 10.1093/jhered/esab019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 04/13/2021] [Indexed: 02/07/2023] Open
Abstract
A current challenge in the fields of evolutionary, ecological, and conservation genomics is balancing production of large-scale datasets with additional training often required to handle such datasets. Thus, there is an increasing need for conservation geneticists to continually learn and train to stay up-to-date through avenues such as symposia, meetings, and workshops. The ConGen meeting is a near-annual workshop that strives to guide participants in understanding population genetics principles, study design, data processing, analysis, interpretation, and applications to real-world conservation issues. Each year of ConGen gathers a diverse set of instructors, students, and resulting lectures, hands-on sessions, and discussions. Here, we summarize key lessons learned from the 2019 meeting and more recent updates to the field with a focus on big data in conservation genomics. First, we highlight classical and contemporary issues in study design that are especially relevant to working with big datasets, including the intricacies of data filtering. We next emphasize the importance of building analytical skills and simulating data, and how these skills have applications within and outside of conservation genetics careers. We also highlight recent technological advances and novel applications to conservation of wild populations. Finally, we provide data and recommendations to support ongoing efforts by ConGen organizers and instructors-and beyond-to increase participation of underrepresented minorities in conservation and eco-evolutionary sciences. The future success of conservation genetics requires both continual training in handling big data and a diverse group of people and approaches to tackle key issues, including the global biodiversity-loss crisis.
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Affiliation(s)
- Rena M Schweizer
- Division of Biological Sciences, University of Montana, Missoula, MT
| | - Norah Saarman
- Department of Biology, Utah State University, Logan, UT
| | - Kristina M Ramstad
- Department of Biology and Geology, University of South Carolina Aiken, Aiken, SC
| | | | - Joanna L Kelley
- School of Biological Sciences, Washington State University, Pullman, WA
| | - Brian K Hand
- Division of Biological Sciences, University of Montana, Missoula, MT.,Flathead Lake Biological Station, University of Montana, Polson, MT
| | - Rachel L Malison
- Flathead Lake Biological Station, University of Montana, Polson, MT
| | - Amanda S Ackiss
- Wisconsin Cooperative Fishery Research Unit, University of Wisconsin Stevens Point, Stevens Point, WI
| | | | | | - Albano Beja-Pereira
- Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-UP), InBIO, Universidade do Porto, Vairão, Portugal.,DGAOT, Faculty of Sciences, University of Porto, Porto, Portugal.,Sustainable Agrifood Production Research Centre (GreenUPorto), Faculty of Sciences, University of Porto, Porto, Portugal
| | - Robin S Waples
- Northwest Fisheries Science Center, NOAA Fisheries, Seattle, WA
| | - W Chris Funk
- Department of Biology, Graduate Degree Program in Ecology, Colorado State University, Fort Collins, CO
| | - Gordon Luikart
- Division of Biological Sciences, University of Montana, Missoula, MT.,Flathead Lake Biological Station, University of Montana, Polson, MT
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Klein JD, der Merwe AEBV, Dicken ML, Emami-Khoyi A, Mmonwa KL, Teske PR. A globally threatened shark, Carcharias taurus, shows no population decline in South Africa. Sci Rep 2020; 10:17959. [PMID: 33087802 PMCID: PMC7578018 DOI: 10.1038/s41598-020-75044-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/09/2020] [Indexed: 12/03/2022] Open
Abstract
Knowledge about the demographic histories of natural populations helps to evaluate their conservation status, and potential impacts of natural and anthropogenic pressures. In particular, estimates of effective population size obtained through molecular data can provide useful information to guide management decisions for vulnerable populations. The spotted ragged-tooth shark, Carcharias taurus (also known as the sandtiger or grey nurse shark), is widely distributed in warm-temperate and subtropical waters, but has suffered severe population declines across much of its range as a result of overexploitation. Here, we used multilocus genotype data to investigate the demographic history of the South African C. taurus population. Using approximate Bayesian computation and likelihood-based importance sampling, we found that the population underwent a historical range expansion that may have been linked to climatic changes during the late Pleistocene. There was no evidence for a recent anthropogenic decline. Together with census data suggesting a stable population, these results support the idea that fishing pressure and other threats have so far not been detrimental to the local C. taurus population. The results reported here indicate that South Africa could possibly harbour the last remaining, relatively pristine population of this widespread but vulnerable top predator.
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Affiliation(s)
- Juliana D Klein
- Molecular Breeding and Biodiversity Group, Department of Genetics, Stellenbosch University, Stellenbosch, 7600, South Africa
- Centre for Ecological Genomics and Wildlife Conservation, Department of Zoology, University of Johannesburg, Auckland Park, 2006, South Africa
| | - Aletta E Bester-van der Merwe
- Molecular Breeding and Biodiversity Group, Department of Genetics, Stellenbosch University, Stellenbosch, 7600, South Africa
| | - Matthew L Dicken
- KwaZulu-Natal Sharks Board, Umhlanga Rocks, 4320, South Africa
- Department of Development Studies, School of Economics, Development and Tourism, Nelson Mandela University, Port Elizabeth, 6031, South Africa
| | - Arsalan Emami-Khoyi
- Centre for Ecological Genomics and Wildlife Conservation, Department of Zoology, University of Johannesburg, Auckland Park, 2006, South Africa
| | - Kolobe L Mmonwa
- KwaZulu-Natal Sharks Board, Umhlanga Rocks, 4320, South Africa
| | - Peter R Teske
- Centre for Ecological Genomics and Wildlife Conservation, Department of Zoology, University of Johannesburg, Auckland Park, 2006, South Africa.
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Genome-wide SNPs detect no evidence of genetic population structure for reef manta rays (Mobula alfredi) in southern Mozambique. Heredity (Edinb) 2020; 126:308-319. [PMID: 33005043 DOI: 10.1038/s41437-020-00373-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 09/13/2020] [Accepted: 09/14/2020] [Indexed: 11/08/2022] Open
Abstract
Little is known about the extent of genetic connectivity along continuous coastlines in manta rays, or whether site visitation is influenced by relatedness. Such information is pertinent to defining population boundaries and understanding localized dispersal patterns and behaviour. Here, we use 3057 genome-wide single-nucleotide polymorphisms (SNPs) to evaluate population genetic structure and assess the levels of relatedness at aggregation sites of reef manta rays (Mobula alfredi) in southern Mozambique (n = 114). Contrary to indications of limited dispersal along the southern Mozambican coastline inferred from photo-identification and telemetry studies, our results show no evidence of population structure (non-significant FST < 0.001) for M. alfredi along this coast. We also found no evidence that individuals sampled at the same site were more related than expected by chance for males, females or across both sexes, suggesting that kinship may not influence visitation patterns at these sites. We estimated the effective population size (Ne) of this population to be 375 (95% CI = 369-380). Comparison to a distant eastern Indian Ocean site (Western Australia, n = 15) revealed strong genetic differentiation between Mozambique and Western Australia (FST = 0.377), identifying the Indian Ocean basin as a barrier to dispersal. Our findings show that genetic connectivity in M. alfredi extends for several hundred kilometres along continuous coastlines. We therefore recommend that the population in Mozambique be considered a discrete management unit, and future conservation plans should prioritize integrated strategies along the entire southern coastline.
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Antao T, Cosart T, Trethewey B, Waples RS, Ackerman MW, Luikart G, Hand BK. AgeStrucNb: Software for Simulating and Detecting Changes in the Effective Number of Breeders (Nb). J Hered 2020. [DOI: 10.1093/jhered/esaa028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Estimation of the effective number of breeders per reproductive event (Nb) using single sample DNA-marker-based methods has rapidly grown in recent years. However, estimating Nb is difficult in age-structured populations because the performance of estimators is influenced by the Nb / Ne ratio, which varies among species with different life histories. We provide a computer program, AgeStrucNb, to simulate age-structured populations (including life history) and also estimate Nb. The AgeStrucNb program is composed of 4 major components to simulate, subsample, estimate, and then visualize Nb time series data. AgeStrucNb allows users to also quantify the precision and accuracy of any set of loci or sample size to estimate Nb for many species and populations. AgeStrucNb allows users to conduct power analysis to evaluate sensitivity to detect changes in Nb or the power to detect a correlation between trends in Nb and environmental variables (e.g., temperature, habitat quality, predator or pathogen abundance) that could be driving changes in Nb. The software provides Nb estimates for empirical data sets using the LDNe (linkage disequilibrium) method, includes publication-quality output graphs, and outputs genotype files in Genepop format for use in other programs. AgeStrucNb will help advance the application of genetic markers for monitoring Nb, which will help biologists to detect population declines and growth, which is crucial for research and conservation of natural and managed populations.
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Affiliation(s)
- Tiago Antao
- Division of Biological Sciences, The University of Montana, Missoula, MT
| | - Ted Cosart
- Flathead Lake Biological Station, University of Montana, Polson, MT
| | | | - Robin S Waples
- NOAA Fisheries, Northwest Fisheries Science Center, Seattle, WA
| | | | - Gordon Luikart
- Division of Biological Sciences, The University of Montana, Missoula, MT
- Flathead Lake Biological Station, University of Montana, Polson, MT
| | - Brian K Hand
- Division of Biological Sciences, The University of Montana, Missoula, MT
- Flathead Lake Biological Station, University of Montana, Polson, MT
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11
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Jones AT, Lavery SD, Le Port A, Wang YG, Blower D, Ovenden J. Sweepstakes reproductive success is absent in a New Zealand snapper (Chrysophrus auratus) population protected from fishing despite "tiny" N e /N ratios elsewhere. Mol Ecol 2019; 28:2986-2995. [PMID: 31087739 DOI: 10.1111/mec.15130] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 04/30/2019] [Accepted: 05/01/2019] [Indexed: 01/07/2023]
Abstract
A landmark study published in 2002 estimated a very small Ne /N ratio (around 10-5 ) in a population of pink snapper (Chrysophrys auratus, Forster, 1801) in the Hauraki Gulf in New Zealand. It epitomized the tiny Ne /N ratios (<10-3 ) reported in marine species due to the hypothesized operation of sweepstakes reproductive success (SRS). Here we re-evaluate the occurrence of SRS in marine species and the potential effect of fishing on the Ne /N ratio by studying the same species in the same region, but in a population that has been protected from fishing since 1975. We combine empirical, simulation and model-based approaches to estimate Ne (and Nb ) from genotypes of 1,044 adult fish and estimate N using recapture-probabilities. The estimated Ne /N ratio was much larger (0.33, SE: 0.14) than expected. The magnitude of estimates of population-wide variance in individual lifetime reproductive success (10-18) suggested that the sweepstakes effect was negligible in the study population. After evaluating factors that could explain the contrast between studies - experimental design, life history differences, environmental effects and the influence of exploitation on the Ne /N ratio - we conclude that the low Ne of the Hauraki Gulf population is associated with demographic instability in the harvested compared to the protected population despite circumstantial evidence that the 2002 study may have underestimated Ne . This study has broad implications for the prevailing view that reproductive success in the sea is largely driven by chance, and for genetic monitoring of populations using the Ne /N ratio and Nb .
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Affiliation(s)
- Andrew T Jones
- School of Mathematics and Physics, University of Queensland, Brisbane, Queensland, Australia
| | - Shane D Lavery
- School of Biological Sciences, University of Auckland, Auckland, New Zealand.,Institute of Marine Science, University of Auckland, Auckland, New Zealand
| | - Agnès Le Port
- Institute of Marine Science, University of Auckland, Auckland, New Zealand.,Centre for Sustainable Tropical Fisheries and Aquaculture, James Cook University, Townsville, Queensland, Australia
| | - You-Gan Wang
- Science and Engineering Faculty, School of Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Dean Blower
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia.,Molecular Fisheries Laboratory and School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Jennifer Ovenden
- Molecular Fisheries Laboratory and School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, Australia
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