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Tan B, Zhang D, Tian Y, Mao J, Wang X, Wang L, Chang Y, Hao Z. Genetic structure and local adaptation of Neptunea cumingii crosse populations in China based on GBS technology. Front Ecol Evol 2023. [DOI: 10.3389/fevo.2023.1154781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/14/2023] Open
Abstract
To identify the genetic characteristics and local adaptation mechanism of the snail Neptunea cumingii in different sea areas of China, specimens from six coastal areas of the Yellow Sea and Bohai Sea were collected. Simplified genome technology was used to study the population genetic structure and genetic diversity level of N. cumingii and to infer the genetic variation pattern of environmental adaptation of this species. In total, 1992 discrete loci with high quality were obtained used for population genomics analysis. The observed heterozygosity was 0.1551–0.1612, and the expected heterozygosity was 0.1064–0.1117. Nucleotide diversity ranged from 0.1120 to 0.1241, and fixation index values ranged from −0.04683 to −0.02041. A total of 330 discrete loci were screened based on two fixation index values and a method associated with environmental factors. Functional annotation showed that the genes of discrete loci were involved in the three major functions of cell composition, biological process, and molecular function, including growth and development and cell metabolism and catalytic activity. These results suggested that different populations of N. cumingii had loci that may be related to local adaptation. The results of this study helped to clarify the level of genetic diversity and the germplasm genetic background of N. cumingii. They also provided information about the genetic mechanism of environmental adaptation of N. cumingii that can be applied to the restoration and management of N. cumingii resources.
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2
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Besnier F, Ayllon F, Skaala Ø, Solberg MF, Fjeldheim PT, Anderson K, Knutar S, Glover KA. Introgression of domesticated salmon changes life history and phenology of a wild salmon population. Evol Appl 2022; 15:853-864. [PMID: 35603027 PMCID: PMC9108307 DOI: 10.1111/eva.13375] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 03/03/2022] [Accepted: 03/09/2022] [Indexed: 11/29/2022] Open
Affiliation(s)
- F. Besnier
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
| | - F. Ayllon
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
| | - Ø. Skaala
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
| | - M. F. Solberg
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
| | | | - K. Anderson
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
| | - S. Knutar
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
| | - K. A. Glover
- Institute of Marine Research PO box 1870 Nordnes N‐5817 Norway
- Department of Biological Sciences University of Bergen N‐5020 Bergen Norway
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3
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Brookes B, Jeon H, Derry AM, Post JR, Rogers SM, Humphries S, Fraser DJ. Neutral and adaptive drivers of genomic change in introduced brook trout ( Salvelinus fontinalis) populations revealed by pooled sequencing. Ecol Evol 2022; 12:e8584. [PMID: 35154655 PMCID: PMC8820109 DOI: 10.1002/ece3.8584] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/07/2022] [Indexed: 12/22/2022] Open
Abstract
Understanding the drivers of successful species invasions is important for conserving native biodiversity and for mitigating the economic impacts of introduced species. However, whole-genome resolution investigations of the underlying contributions of neutral and adaptive genetic variation in successful introductions are rare. Increased propagule pressure should result in greater neutral genetic variation, while environmental differences should elicit selective pressures on introduced populations, leading to adaptive differentiation. We investigated neutral and adaptive variation among nine introduced brook trout (Salvelinus fontinalis) populations using whole-genome pooled sequencing. The populations inhabit isolated alpine lakes in western Canada and descend from a common source, with an average of ~19 (range of 7-41) generations since introduction. We found some evidence of bottlenecks without recovery, no strong evidence of purifying selection, and little support that varying propagule pressure or differences in local environments shaped observed neutral genetic variation differences. Putative adaptive loci analysis revealed nonconvergent patterns of adaptive differentiation among lakes with minimal putatively adaptive loci (0.001%-0.15%) that did not correspond with tested environmental variables. Our results suggest that (i) introduction success is not always strongly influenced by genetic load; (ii) observed differentiation among introduced populations can be idiosyncratic, population-specific, or stochastic; and (iii) conservatively, in some introduced species, colonization barriers may be overcome by support through one aspect of propagule pressure or benign environmental conditions.
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Affiliation(s)
- Brent Brookes
- Department of BiologyConcordia UniversityMontréalQCCanada
| | - Hyung‐Bae Jeon
- Department of BiologyConcordia UniversityMontréalQCCanada
| | - Alison M. Derry
- Département des sciences biologiquesUniversité du Québec à MontréalMontréalQCCanada
| | - John R. Post
- Department of BiologyUniversity of CalgaryCalgaryABCanada
| | - Sean M. Rogers
- Department of BiologyUniversity of CalgaryCalgaryABCanada
| | - Shelley Humphries
- Parks CanadaNatural Resource Management BranchRadium Hot SpringsBCCanada
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4
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Berrebi P, Jesenšek D, Laporte M, Crivelli AJ. Restoring marble trout genes in the Soča River (Slovenia). CONSERV GENET 2022. [DOI: 10.1007/s10592-022-01430-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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5
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Genetic Evaluation of Black Sea Bream (Acanthopagrus schlegelii) Stock Enhancement in the South China Sea Based on Microsatellite DNA Markers. FISHES 2021. [DOI: 10.3390/fishes6040047] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This is the first genetic evaluation of hatchery-based stock enhancement of black sea bream (Acanthopagrus schlegelii) in the South China Sea after a two-year monitoring period. In this study, microsatellite DNA markers were used to calculate the contribution rate and analyze genetic changes before and after stock enhancement. Two out of one hundred and sixty nine individuals from three recaptured populations were assigned to broodstock with a contribution rate of 1.18%, revealing that the hatchery-released juvenile fish could survive in the natural environment and had a positive effect on population replenishment in wild black sea bream abundance. However, we found that the release population had the lowest genetic diversity and significant genetic differentiation from other populations. In addition, genetic diversity detected in the recaptured population was lower than that in the wild population, and their genetic differentiation reached a significant level. Our results suggested that releasing cultured black sea bream juveniles with low genetic quality might be genetically harmful for the maintenance of wild genotypes. Therefore, it is necessary to assess the genetic variation of the hatchery population before implementing a stock enhancement and establish a long-term evaluation for monitoring the genetic effect caused by releasing this fish species.
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6
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Faust E, Jansson E, André C, Halvorsen KT, Dahle G, Knutsen H, Quintela M, Glover KA. Not that clean: Aquaculture-mediated translocation of cleaner fish has led to hybridization on the northern edge of the species' range. Evol Appl 2021; 14:1572-1587. [PMID: 34178105 PMCID: PMC8210792 DOI: 10.1111/eva.13220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 03/01/2021] [Accepted: 03/02/2021] [Indexed: 12/11/2022] Open
Abstract
Translocation and introduction of non-native organisms can have major impacts on local populations and ecosystems. Nevertheless, translocations are common practices in agri- and aquaculture. Each year, millions of wild-caught wrasses are transported large distances to be used as cleaner fish for parasite control in marine salmon farms. Recently, it was documented that translocated cleaner fish are able to escape and reproduce with local wild populations. This is especially a challenge in Norway, which is the world's largest salmon producer. Here, a panel of 84 informative SNPs was developed to identify the presence of nonlocal corkwing wrasse (Symphodus melops) escapees and admixed individuals in wild populations in western Norway. Applying this panel to ~2000 individuals, escapees and hybrids were found to constitute up to 20% of the local population at the northern edge of the species' distribution. The introduction of southern genetic material at the northern edge of the species distribution range has altered the local genetic composition and could obstruct local adaptation and further range expansion. Surprisingly, in other parts of the species distribution where salmon farming is also common, few escapees and hybrids were found. Why hybridization seems to be common only in the far north is discussed in the context of demographic and transport history. However, the current lack of reporting of escapes makes it difficult to evaluate possible causes for why some aquaculture-dense areas have more escapees and hybrids than others. The results obtained in this study, and the observed high genomic divergence between the main export and import regions, puts the sustainability of mass translocation of nonlocal wild wrasse into question and suggests that the current management regime needs re-evaluation.
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Affiliation(s)
- Ellika Faust
- Department of Marine Sciences – TjärnöUniversity of GothenburgStrömstadSweden
| | | | - Carl André
- Department of Marine Sciences – TjärnöUniversity of GothenburgStrömstadSweden
| | | | - Geir Dahle
- Institute of Marine ResearchBergenNorway
| | - Halvor Knutsen
- Institute of Marine ResearchHisNorway
- Centre of Coastal ResearchUniversity of AgderKristiansandNorway
| | | | - Kevin A. Glover
- Institute of Marine ResearchBergenNorway
- Institute of BiologyUniversity of BergenBergenNorway
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7
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Wacker S, Aronsen T, Karlsson S, Ugedal O, Diserud OH, Ulvan EM, Hindar K, Næsje TF. Selection against individuals from genetic introgression of escaped farmed salmon in a natural population of Atlantic salmon. Evol Appl 2021; 14:1450-1460. [PMID: 34025778 PMCID: PMC8127704 DOI: 10.1111/eva.13213] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 01/14/2021] [Accepted: 02/26/2021] [Indexed: 11/27/2022] Open
Abstract
The viability of wild Atlantic salmon populations is threatened by genetic introgression from escaped farmed salmon. Farmed Atlantic salmon are genetically improved for important commercial traits and a life in captivity but are poorly adapted to the natural environment. The rate of gene flow from escaped farmed to wild salmon depends on their spawning success and on offspring survival at various life stages. We here investigate relative survival of introgressed juvenile Atlantic salmon (parr) in a river in northern Norway. The studied population has experienced genetic introgression from farmed salmon for about four generations (20 years). We followed two cohorts of parr from the year of hatching (0+) to the age of 2 years (2+). Farmed genetic introgression was quantified at the individual level and on a continuous scale using diagnostic SNPs. Population-level genetic introgression decreased from 0+ to 2+ by 64% (2011 cohort) and 37% (2013 cohort). This change was driven by a 70% (2011 cohort) and 49% (2013 cohort) lower survival from age 0+ to 2+ in introgressed parr compared to parr of wild origin. Our observations show that there is natural selection against genetic introgression with a potential cost of lower productivity.
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Affiliation(s)
| | - Tonje Aronsen
- Norwegian Institute for Nature ResearchTrondheimNorway
| | - Sten Karlsson
- Norwegian Institute for Nature ResearchTrondheimNorway
| | - Ola Ugedal
- Norwegian Institute for Nature ResearchTrondheimNorway
| | | | - Eva M. Ulvan
- Norwegian Institute for Nature ResearchTrondheimNorway
| | - Kjetil Hindar
- Norwegian Institute for Nature ResearchTrondheimNorway
| | - Tor F. Næsje
- Norwegian Institute for Nature ResearchTrondheimNorway
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8
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Leitwein M, Cayuela H, Bernatchez L. Associative Overdominance and Negative Epistasis Shape Genome-Wide Ancestry Landscape in Supplemented Fish Populations. Genes (Basel) 2021; 12:genes12040524. [PMID: 33916757 PMCID: PMC8065892 DOI: 10.3390/genes12040524] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/26/2021] [Accepted: 03/31/2021] [Indexed: 02/06/2023] Open
Abstract
The interplay between recombination rate, genetic drift and selection modulates variation in genome-wide ancestry. Understanding the selective processes at play is of prime importance toward predicting potential beneficial or negative effects of supplementation with domestic strains (i.e., human-introduced strains). In a system of lacustrine populations supplemented with a single domestic strain, we documented how population genetic diversity and stocking intensity produced lake-specific patterns of domestic ancestry by taking the species’ local recombination rate into consideration. We used 552 Brook Charr (Salvelinus fontinalis) from 22 small lacustrine populations, genotyped at ~32,400 mapped SNPs. We observed highly variable patterns of domestic ancestry between each of the 22 populations without any consistency in introgression patterns of the domestic ancestry. Our results suggest that such lake-specific ancestry patterns were mainly due to variable associative overdominance (AOD) effects among populations (i.e., potential positive effects due to the masking of possible deleterious alleles in low recombining regions). Signatures of AOD effects were also emphasized by highly variable patterns of genetic diversity among and within lakes, potentially driven by predominant genetic drift in those small isolated populations. Local negative effects such as negative epistasis (i.e., potential genetic incompatibilities between the native and the introduced population) potentially reflecting precursory signs of outbreeding depression were also observed at a chromosomal scale. Consequently, in order to improve conservation practices and management strategies, it became necessary to assess the consequences of supplementation at the population level by taking into account both genetic diversity and stocking intensity when available.
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9
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Bootsma ML, Miller L, Sass GG, Euclide PT, Larson WA. The ghosts of propagation past: haplotype information clarifies the relative influence of stocking history and phylogeographic processes on contemporary population structure of walleye ( Sander vitreus). Evol Appl 2021; 14:1124-1144. [PMID: 33897825 PMCID: PMC8061267 DOI: 10.1111/eva.13186] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 12/05/2020] [Accepted: 12/07/2020] [Indexed: 12/13/2022] Open
Abstract
Stocking of fish is an important tool for maintaining fisheries but can also significantly alter population genetic structure and erode the portfolio of within-species diversity that is important for promoting resilience and adaptability. Walleye (Sander vitreus) are a highly valued sportfish in the midwestern United States, a region characterized by postglacial recolonization from multiple lineages and an extensive history of stocking. We leveraged genomic data and recently developed analytical approaches to explore the population structure of walleye from two midwestern states, Minnesota and Wisconsin. We genotyped 954 walleye from 23 populations at ~20,000 loci using genotyping by sequencing and tested for patterns of population structure with single-SNP and microhaplotype data. Populations from Minnesota and Wisconsin were highly differentiated from each other, with additional substructure found in each state. Population structure did not consistently adhere to drainage boundaries, as cases of high intra-drainage and low inter-drainage differentiation were observed. Low genetic structure was observed between populations from the upper Wisconsin and upper Chippewa river watersheds, which are found as few as 50 km apart and were likely homogenized through historical stocking. Nevertheless, we were able to differentiate these populations using microhaplotype-based co-ancestry analysis, providing increased resolution over previous microsatellite studies and our other single SNP-based analyses. Although our results illustrate that walleye population structure has been influenced by past stocking practices, native ancestry still exists in most populations and walleye populations may be able to purge non-native alleles and haplotypes in the absence of stocking. Our study is one of the first to use genomic tools to investigate the influence of stocking on population structure in a nonsalmonid fish and outlines a workflow leveraging recently developed analytical methods to improve resolution of complex population structure that will be highly applicable in many species and systems.
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Affiliation(s)
- Matthew L. Bootsma
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWIUSA
| | - Loren Miller
- Minnesota Department of Natural ResourcesUniversity of MinnesotaSt. PaulMNUSA
| | - Greg G. Sass
- Office of Applied ScienceWisconsin Department of Natural ResourcesEscanaba Lake Research StationBoulder JunctionWIUSA
| | - Peter T. Euclide
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWIUSA
| | - Wesley A. Larson
- U.S. Geological SurveyWisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWIUSA
- Present address:
Ted Stevens Marine Research InstituteAlaska Fisheries Science CenterNational Marine Fisheries ServiceNational Oceanic and Atmospheric AdministrationJuneauAKUSA
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10
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Garant D. Natural and human-induced environmental changes and their effects on adaptive potential of wild animal populations. Evol Appl 2020; 13:1117-1127. [PMID: 32684950 PMCID: PMC7359845 DOI: 10.1111/eva.12928] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 01/23/2020] [Accepted: 01/24/2020] [Indexed: 12/26/2022] Open
Abstract
A major challenge of evolutionary ecology over the next decades is to understand and predict the consequences of the current rapid and important environmental changes on wild populations. Extinction risk of species is linked to populations' evolutionary potential and to their ability to express adaptive phenotypic plasticity. There is thus a vital need to quantify how selective pressures, quantitative genetics parameters, and phenotypic plasticity, for multiple traits in wild animal populations, may vary with changes in the environment. Here I review our previous research that integrated ecological and evolutionary theories with molecular ecology, quantitative genetics, and long-term monitoring of individually marked wild animals. Our results showed that assessing evolutionary and plastic changes over time and space, using multi-trait approaches, under a realistic range of environmental conditions are crucial steps toward improving our understanding of the evolution and adaptation of natural populations. Our current and future work focusses on assessing the limits of adaptive potential by determining the factors constraining the evolvability of plasticity, those generating covariation among genetic variance and selection, as well as indirect genetic effects, which can affect population's capacity to adjust to environmental changes. In doing so, we aim to provide an improved assessment of the spatial and temporal scale of evolutionary processes in wild animal populations.
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Affiliation(s)
- Dany Garant
- Département de biologieFaculté des SciencesUniversité de SherbrookeSherbrookeQCCanada
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11
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Effects of genetic origin on phenotypic divergence in Brook Trout populations stocked with domestic fish. Ecosphere 2020. [DOI: 10.1002/ecs2.3119] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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12
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Lehnert SJ, Baillie SM, MacMillan J, Paterson IG, Buhariwalla CF, Bradbury IR, Bentzen P. Multiple decades of stocking has resulted in limited hatchery introgression in wild brook trout ( Salvelinus fontinalis) populations of Nova Scotia. Evol Appl 2020; 13:1069-1089. [PMID: 32431753 PMCID: PMC7232767 DOI: 10.1111/eva.12923] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Revised: 12/06/2019] [Accepted: 12/17/2019] [Indexed: 12/17/2022] Open
Abstract
Many populations of freshwater fishes are threatened with losses, and increasingly, the release of hatchery individuals is one strategy being implemented to support wild populations. However, stocking of hatchery individuals may pose long-term threats to wild populations, particularly if genetic interactions occur between wild and hatchery individuals. One highly prized sport fish that has been heavily stocked throughout its range is the brook trout (Salvelinus fontinalis). In Nova Scotia, Canada, hatchery brook trout have been stocked since the early 1900s, and despite continued stocking efforts, populations have suffered declines in recent decades. Before this study, the genetic structure of brook trout populations in the province was unknown; however, given the potential negative consequences associated with hatchery stocking, it is possible that hatchery programs have adversely affected the genetic integrity of wild populations. To assess the influence of hatchery supplementation on wild populations, we genotyped wild brook trout from 12 river systems and hatchery brook trout from two major hatcheries using 100 microsatellite loci. Genetic analyses of wild trout revealed extensive population genetic structure among and within river systems and significant isolation-by-distance. Hatchery stocks were genetically distinct from wild populations, and most populations showed limited to no evidence of hatchery introgression (<5% hatchery ancestry). Only a single location had a substantial number of hatchery-derived trout and was located in the only river where a local strain is used for supplementation. The amount of hatchery stocking within a watershed did not influence the level of hatchery introgression. Neutral genetic structure of wild populations was influenced by geography with some influence of climate and stocking indices. Overall, our study suggests that long-term stocking has not significantly affected the genetic integrity of wild trout populations, highlighting the variable outcomes of stocking and the need to evaluate the consequences on a case-by-case basis.
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Affiliation(s)
- Sarah J. Lehnert
- Fisheries and Oceans CanadaNorthwest Atlantic Fisheries CentreSt. John'sNLCanada
| | - Shauna M. Baillie
- Marine Gene Probe LabBiology DepartmentDalhousie UniversityHalifaxNSCanada
| | - John MacMillan
- Inland Fisheries DivisionNova Scotia Department of Fisheries and AquaculturePictouNSCanada
| | - Ian G. Paterson
- Marine Gene Probe LabBiology DepartmentDalhousie UniversityHalifaxNSCanada
| | - Colin F. Buhariwalla
- Inland Fisheries DivisionNova Scotia Department of Fisheries and AquaculturePictouNSCanada
| | - Ian R. Bradbury
- Fisheries and Oceans CanadaNorthwest Atlantic Fisheries CentreSt. John'sNLCanada
- Marine Gene Probe LabBiology DepartmentDalhousie UniversityHalifaxNSCanada
| | - Paul Bentzen
- Marine Gene Probe LabBiology DepartmentDalhousie UniversityHalifaxNSCanada
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13
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Abstract
Salmon were among the first nonmodel species for which systematic population genetic studies of natural populations were conducted, often to support management and conservation. The genomics revolution has improved our understanding of the evolutionary ecology of salmon in two major ways: (a) Large increases in the numbers of genetic markers (from dozens to 104-106) provide greater power for traditional analyses, such as the delineation of population structure, hybridization, and population assignment, and (b) qualitatively new insights that were not possible with traditional genetic methods can be achieved by leveraging detailed information about the structure and function of the genome. Studies of the first type have been more common to date, largely because it has taken time for the necessary tools to be developed to fully understand the complex salmon genome. We expect that the next decade will witness many new studies that take full advantage of salmonid genomic resources.
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Affiliation(s)
- Robin S Waples
- Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, Washington 98112, USA;
| | - Kerry A Naish
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington 98195-5020, USA;
| | - Craig R Primmer
- Organismal & Evolutionary Biology Research Program and Biotechnology Institute, University of Helsinki, 00014 Helsinki, Finland;
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14
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Leitwein M, Cayuela H, Ferchaud AL, Normandeau É, Gagnaire PA, Bernatchez L. The role of recombination on genome-wide patterns of local ancestry exemplified by supplemented brook charr populations. Mol Ecol 2019; 28:4755-4769. [PMID: 31579957 DOI: 10.1111/mec.15256] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/23/2019] [Accepted: 09/24/2019] [Indexed: 12/14/2022]
Abstract
Assessing the immediate and long-term evolutionary consequences of human-mediated hybridization is of major concern for conservation biology. Several studies have documented how selection in interaction with recombination modulates introgression at a genome-wide scale, but few have considered the dynamics of this process within and among chromosomes. Here, we used an exploited freshwater fish, the brook charr (Salvelinus fontinalis), for which decades of stocking practices have resulted in admixture between wild populations and an introduced domestic strain, to assess both the temporal dynamics and local chromosomal variation in domestic ancestry. We provide a detailed picture of the domestic ancestry patterns across the genome using about 33,000 mapped single nucleotide polymorphisms genotyped in 611 individuals from 24 supplemented populations. For each lake, we distinguished early- and late-generation hybrids using information regarding admixture tracts. To assess the selective outcomes following admixture we then evaluated the relationship between recombination and admixture proportions at three different scales: the whole genome, chromosomes and within 2-Mb windows. This allowed us to detect a wide range of evolutionary mechanisms varying along the genome, as reflected by the finding of favoured or disfavoured introgression of domestic haplotypes. Among these, the main factor modulating local ancestry was probably the presence of deleterious recessive mutations in the wild populations, which can be efficiently hidden to selection in the presence of long admixture tracts. Overall, our results emphasize the relevance of taking into consideration local ancestry information to assess both the temporal and the chromosomal variation in local admixture ancestry toward better understanding post-hybridization evolutionary outcomes.
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Affiliation(s)
- Maeva Leitwein
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Hugo Cayuela
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Anne-Laure Ferchaud
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | - Éric Normandeau
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
| | | | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Québec, QC, Canada
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15
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Mandeville EG, Walters AW, Nordberg BJ, Higgins KH, Burckhardt JC, Wagner CE. Variable hybridization outcomes in trout are predicted by historical fish stocking and environmental context. Mol Ecol 2019; 28:3738-3755. [PMID: 31294488 DOI: 10.1111/mec.15175] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 06/14/2019] [Accepted: 06/18/2019] [Indexed: 12/11/2022]
Abstract
Hybridization can profoundly affect the genomic composition and phenotypes of closely related species, and provides an opportunity to identify mechanisms that maintain reproductive isolation between species. Recent evidence suggests that hybridization outcomes within a species pair can vary across locations. However, we still do not know how variable outcomes of hybridization are across geographic replicates, and what mechanisms drive that variation. In this study, we described hybridization outcomes across 27 locations in the North Fork Shoshone River basin (Wyoming, USA) where native Yellowstone cutthroat trout and introduced rainbow trout co-occur. We used genomic data and hierarchical Bayesian models to precisely identify ancestry of hybrid individuals. Hybridization outcomes varied across locations. In some locations, only rainbow trout and advanced backcrossed hybrids towards rainbow trout were present, while trout in other locations had a broader range of ancestry, including both parental species and first-generation hybrids. Later-generation intermediate hybrids were rare relative to backcrossed hybrids and rainbow trout individuals. Using an individual-based simulation, we found that outcomes of hybridization in the North Fork Shoshone River basin deviate substantially from what we would expect under null expectations of random mating and no selection against hybrids. Since this deviation implies that some mechanisms of reproductive isolation function to maintain parental taxa and a diversity of hybrid types, we then modelled hybridization outcomes as a function of environmental variables and stocking history that are likely to affect prezygotic barriers to hybridization. Variables associated with history of fish stocking were the strongest predictors of hybridization outcomes, followed by environmental variables that might affect overlap in spawning time and location.
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Affiliation(s)
- Elizabeth G Mandeville
- Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA.,Department of Botany, University of Wyoming, Laramie, WY, USA.,Department of Integrative Biology, University of Guelph, Guelph, ON, Canada
| | - Annika W Walters
- U.S. Geological Survey, Wyoming Cooperative Fish and Wildlife Research Unit, University of Wyoming, Laramie, WY, USA.,Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA
| | - Brittany J Nordberg
- Department of Botany, University of Wyoming, Laramie, WY, USA.,Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA
| | - Karly H Higgins
- Department of Botany, University of Wyoming, Laramie, WY, USA.,Department of Zoology and Physiology, University of Wyoming, Laramie, WY, USA.,Department of Quantitative and Systems Biology, University of California Merced, Merced, CA, USA
| | | | - Catherine E Wagner
- Department of Botany, University of Wyoming, Laramie, WY, USA.,Biodiversity Institute, University of Wyoming, Laramie, WY, USA
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16
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Beer SD, Cornett S, Austerman P, Trometer B, Hoffman T, Bartron ML. Genetic diversity, admixture, and hatchery influence in Brook Trout ( Salvelinus fontinalis) throughout western New York State. Ecol Evol 2019; 9:7455-7479. [PMID: 31346416 PMCID: PMC6635958 DOI: 10.1002/ece3.5237] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/22/2019] [Accepted: 04/16/2019] [Indexed: 02/06/2023] Open
Abstract
Although Brook Trout are distributed across most of eastern North America, population numbers have declined in many regions due to habitat loss, climate change, and competition with non-native species. In New York State, Brook Trout habitat has been substantially reduced, with many areas showing complete extirpation of Brook Trout populations, predominantly in the western portion of the state. Small, fragmented populations are at risk of genetic diversity loss, inbreeding depression, and reduced fitness, leading to a greater potential for local extirpation. Genetic monitoring is a practical tool that can facilitate further conservation-decision making regarding small populations. In this study, we used 12 microsatellite loci to examine 3,436 sampled Brook Trout, representing 75 sites from the Allegheny, Erie/Niagara, Genesee, Oswego, Lake Ontario, and Susquehanna drainage basins throughout western New York State. Three Brook Trout hatchery strains were also genetically characterized to evaluate the degree of hatchery introgression between wild populations and hatchery strains stocked in the region. Overall, estimates of genetic diversity varied widely: Allelic richness ranged from 2.23 to 7.485, and expected heterozygosity ranged from 0.402 to 0.766. As observed for Brook Trout in other regions, we found a high degree of genetic differentiation among populations, with all comparisons except one showing significant F ST values. Hatchery introgression was found to be minimal, with estimates ranging from 1.96% to 3.10% of wild individuals exhibiting membership proportions to a hatchery strain cluster exceeding 10% (q ≥ 0.10). Results from this investigation can be used to prioritize management efforts for Brook Trout in western New York State and act as a baseline to monitor future population trends.
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Affiliation(s)
| | - Scott Cornett
- New York State Department of Environmental ConservationAlleganyNew York
| | - Peter Austerman
- New York State Department of Environmental ConservationAvonNew York
| | - Betsy Trometer
- U.S. Fish and Wildlife ServiceLower Great Lakes Fish and Wildlife Conservation OfficeBasomNew York
| | - Thomas Hoffman
- U.S. Fish and Wildlife ServiceLower Great Lakes Fish and Wildlife Conservation OfficeBasomNew York
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17
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Bruce SA, Daniel PC, Krause MK, Henson FG, Pershyn CE, Wright JJ. A methodological approach to the genetic identification of native Brook Trout (Salvelinus fontinalis) populations for conservation purposes. Glob Ecol Conserv 2019. [DOI: 10.1016/j.gecco.2019.e00682] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
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18
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Rougemont Q, Carrier A, Le Luyer J, Ferchaud A, Farrell JM, Hatin D, Brodeur P, Bernatchez L. Combining population genomics and forward simulations to investigate stocking impacts: A case study of Muskellunge ( Esox masquinongy) from the St. Lawrence River basin. Evol Appl 2019; 12:902-922. [PMID: 31080504 PMCID: PMC6503833 DOI: 10.1111/eva.12765] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 12/17/2018] [Indexed: 01/03/2023] Open
Abstract
Understanding the genetic and evolutionary impacts of stocking on wild fish populations has long been of interest as negative consequences such as reduced fitness and loss of genetic diversity are commonly reported outcomes. In an attempt to sustain a fishery, managers implemented nearly five decades of extensive stocking of over a million Muskellunge (Esox masquinongy), a native species in the Lower St. Lawrence River (Québec, Canada). We investigated the effect of this stocking on population genetic structure and allelic diversity in the St. Lawrence River in addition to tributaries and several stocked inland lakes. Using genotype by sequencing, we genotyped 643 individuals representing 22 locations and combined this information with forward simulations to investigate the genetic consequences of long-term stocking. Individuals native to the St. Lawrence watershed were genetically differentiated from stocking sources and tributaries, and inland lakes were naturally differentiated from the main river. Empirical data and simulations within the St. Lawrence River revealed weak stocking effects on admixture patterns. Our data suggest that the genetic structure associated with stocked fish was diluted into its relatively large effective population size. This interpretation is also consistent with a hypothesis that selection against introgression was in operation and relatively efficient within the large St. Lawrence River system. In contrast, smaller populations from adjacent tributaries and lakes displayed greater stocking-related admixture that resulted in comparatively higher heterozygosity than the St. Lawrence. Finally, individuals from inland lakes that were established by stocking maintained a close affinity with their source populations. This study illustrated a benefit of combining extensive genomic data with forward simulations for improved inference regarding population-level genetic effects of long-term stocking, and its relevance for fishery management decision making.
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Affiliation(s)
- Quentin Rougemont
- Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada
| | - Anne Carrier
- Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada
| | - Jeremy Le Luyer
- Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada
- IFREMER, Unité Ressources Marines en Polynésie, Centre Océanologique du PacifiqueTaravao, TahitiFrench Polynesia
| | - Anne‐Laure Ferchaud
- Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada
| | - John M. Farrell
- Department of Environmental and Forest Biology, College of Environmental Science and ForestryState University of New YorkSyracuseNew York
| | - Daniel Hatin
- Ministère des Forêts, de la Faune et des Parcs, Direction de la Gestion de la FauneEstrie‐Montréal‐Montérégie‐LavalLongueuilQuébecCanada
| | - Philippe Brodeur
- Ministère des Forêts, de la Faune et des ParcsDirection de la gestion de la faune de la Mauricie et du Centre‐du‐QuébecTrois‐RivièresQuebecCanada
| | - Louis Bernatchez
- Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQuébecCanada
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19
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Mérot C, Berdan EL, Babin C, Normandeau E, Wellenreuther M, Bernatchez L. Intercontinental karyotype-environment parallelism supports a role for a chromosomal inversion in local adaptation in a seaweed fly. Proc Biol Sci 2019; 285:rspb.2018.0519. [PMID: 29925615 PMCID: PMC6030540 DOI: 10.1098/rspb.2018.0519] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 05/24/2018] [Indexed: 12/20/2022] Open
Abstract
Large chromosomal rearrangements are thought to facilitate adaptation to heterogeneous environments by limiting genomic recombination. Indeed, inversions have been implicated in adaptation along environmental clines and in ecotype specialization. Here, we combine classical ecological studies and population genetics to investigate an inversion polymorphism previously documented in Europe among natural populations of the seaweed fly Coelopa frigida along a latitudinal cline in North America. We test if the inversion is present in North America and polymorphic, assess which environmental conditions modulate the inversion karyotype frequencies, and document the relationship between inversion karyotype and adult size. We sampled nearly 2000 flies from 20 populations along several environmental gradients to quantify associations of inversion frequencies to heterogeneous environmental variables. Genotyping and phenotyping showed a widespread and conserved inversion polymorphism between Europe and America. Variation in inversion frequency was significantly associated with environmental factors, with parallel patterns between continents, indicating that the inversion may play a role in local adaptation. The three karyotypes of the inversion are differently favoured across micro-habitats and represent life-history strategies likely to be maintained by the collective action of several mechanisms of balancing selection. Our study adds to the mounting evidence that inversions are facilitators of adaptation and enhance within-species diversity.
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Affiliation(s)
- Claire Mérot
- Département de biologie, Université Laval, Quebec, Canada
| | - Emma L Berdan
- Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Charles Babin
- Département de biologie, Université Laval, Quebec, Canada
| | | | - Maren Wellenreuther
- School of Biological Sciences, University of Auckland, New Zealand.,Seafood Research Unit, Port Nelson, Nelson, New Zealand
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20
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Gossieaux P, Bernatchez L, Sirois P, Garant D. Impacts of stocking and its intensity on effective population size in Brook Charr (Salvelinus fontinalis) populations. CONSERV GENET 2019. [DOI: 10.1007/s10592-019-01168-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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21
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Gossieaux P, Sirois P, Bernatchez L, Garant D. Introgressive hybridization between wild and domestic individuals and its relationship with parasitism in brook charr Salvelinus fontinalis. JOURNAL OF FISH BIOLOGY 2018; 93:664-673. [PMID: 29992561 DOI: 10.1111/jfb.13752] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 07/03/2018] [Indexed: 06/08/2023]
Abstract
The effects of introgression on parasitism in brook charr Salvelinus fontinalis were investigated in 28 lakes with various levels of stocking in Québec, Canada. No effect of genetic background on parasitism was found at the individual level. Body length seemed to explain most of the variation observed at this level, with largest fish being more infected. However, lakes with the greater average domestic genetic background were found to display significantly lower parasite prevalence and diversity. Since our results indicate no effect of domestic genes at the individual level, the negative association with introgression found at the population level may be mainly attributed to differences in intrinsic environmental quality of lakes (e.g. fishing pressure, availability of food resources, abiotic characteristics).
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Affiliation(s)
- Philippine Gossieaux
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Pascal Sirois
- Chaire de recherche sur les espèces aquatiques exploitées, Département des sciences fondamentales, Université du Québec à Chicoutimi, Chicoutimi, Québec, Canada
| | - Louis Bernatchez
- Département de biologie, Institut de Biologie Intégrative et des Systèmes (IBIS), Université Laval, Pavillon Charles-Eugène-Marchand, Québec, Québec, Canada
| | - Dany Garant
- Département de Biologie, Faculté des Sciences, Université de Sherbrooke, Sherbrooke, Québec, Canada
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22
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White SL, Miller WL, Dowell SA, Bartron ML, Wagner T. Limited hatchery introgression into wild brook trout ( Salvelinus fontinalis) populations despite reoccurring stocking. Evol Appl 2018; 11:1567-1581. [PMID: 30344628 PMCID: PMC6183464 DOI: 10.1111/eva.12646] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Revised: 05/04/2018] [Accepted: 05/07/2018] [Indexed: 01/17/2023] Open
Abstract
Due to increased anthropogenic pressures on many fish populations, supplementing wild populations with captive-raised individuals has become an increasingly common management practice. Stocking programs can be controversial due to uncertainty about the long-term fitness effects of genetic introgression on wild populations. In particular, introgression between hatchery and wild individuals can cause declines in wild population fitness, resiliency, and adaptive potential and contribute to local population extirpation. However, low survival and fitness of captive-raised individuals can minimize the long-term genetic consequences of stocking in wild populations, and to date the prevalence of introgression in actively stocked ecosystems has not been rigorously evaluated. We quantified the extent of introgression in 30 populations of wild brook trout (Salvelinus fontinalis) in a Pennsylvania watershed and examined the correlation between introgression and 11 environmental covariates. Genetic assignment tests were used to determine the origin (wild vs. captive-raised) for 1,742 wild-caught and 300 hatchery brook trout. To avoid assignment biases, individuals were assigned to two simulated populations that represented the average allele frequencies in wild and hatchery groups. Fish with intermediate probabilities of wild ancestry were classified as introgressed, with threshold values determined through simulation. Even with reoccurring stocking at most sites, over 93% of wild-caught individuals probabilistically assigned to wild origin, and only 5.6% of wild-caught fish assigned to introgressed. Models examining environmental drivers of introgression explained <3% of the among-population variability, and all estimated effects were highly uncertain. This was not surprising given overall low introgression observed in this study. Our results suggest that introgression of hatchery-derived genotypes can occur at low rates, even in actively stocked ecosystems and across a range of habitats. However, a cautious approach to stocking may still be warranted, as the potential effects of stocking on wild population fitness and the mechanisms limiting introgression are not known.
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Affiliation(s)
- Shannon L. White
- Pennsylvania Cooperative Fish and Wildlife Research UnitPennsylvania State UniversityUniversity ParkPennsylvania
- Department of Ecosystem Science and ManagementPennsylvania State UniversityUniversity ParkPennsylvania
| | - William L. Miller
- Pennsylvania Cooperative Fish and Wildlife Research UnitPennsylvania State UniversityUniversity ParkPennsylvania
- Department of Ecosystem Science and ManagementPennsylvania State UniversityUniversity ParkPennsylvania
| | | | | | - Tyler Wagner
- U.S. Geological SurveyPennsylvania Cooperative Fish and Wildlife Research UnitPennsylvania State UniversityUniversity ParkPennsylvania
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23
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Ferchaud A, Laporte M, Perrier C, Bernatchez L. Impact of supplementation on deleterious mutation distribution in an exploited salmonid. Evol Appl 2018; 11:1053-1065. [PMID: 30026797 PMCID: PMC6050184 DOI: 10.1111/eva.12660] [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: 08/18/2017] [Revised: 05/31/2018] [Accepted: 06/01/2018] [Indexed: 01/03/2023] Open
Abstract
Deleterious mutations have important implications for the evolutionary trajectories of populations. While several studies recently investigated the dynamics of deleterious mutations in wild populations, no study has yet explored the fate of deleterious mutations in a context of populations managed by supplementation. Here, based on a dataset of nine wild and 15 supplemented Lake Trout populations genotyped at 4,982 single nucleotide polymorphisms (SNP)s by means of genotype by sequencing (GBS), we explored the effect of supplementation on the frequency of putatively deleterious variants. Three main findings are consequential for the management of fish populations. First, an increase in neutral genetic diversity in stocked populations compared with unstocked ones was observed. Second, putatively deleterious mutations were more likely to be found in unstocked than in stocked populations, suggesting a lower efficiency to purge deleterious mutations in unstocked lakes. Third, a population currently used as a major source for supplementation is characterized by several fixed putatively deleterious alleles. Therefore, other source populations with lower abundance of putatively deleterious mutations should be favored as sources of supplementation. We discuss management implications of our results, especially pertaining to the joint identification of neutral and deleterious mutations that could help refining the choice of source and sink populations for supplementation in order to maximize their evolutionary potential and to limit their mutation load.
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Affiliation(s)
- Anne‐Laure Ferchaud
- Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQCCanada
| | - Martin Laporte
- Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQCCanada
| | - Charles Perrier
- Centre d’Écologie Fonctionnelle et ÉvolutiveUnité Mixte de Recherche CNRS 5175Montpellier Cedex 5France
| | - Louis Bernatchez
- Institut de Biologie Intégrative et des Systèmes (IBIS)Université LavalQuébecQCCanada
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24
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Supplementation stocking of Lake Trout (Salvelinus namaycush) in small boreal lakes: Ecotypes influence on growth and condition. PLoS One 2018; 13:e0200599. [PMID: 30001412 PMCID: PMC6042763 DOI: 10.1371/journal.pone.0200599] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 07/01/2018] [Indexed: 11/30/2022] Open
Abstract
Supplementation stocking is a commonly used management tool to sustain exploited fish populations. Possible negative consequences of supplementation on local stocks are a concern for the conservation of wild fish populations. However, the direct impacts of supplementation on life history traits of local populations have rarely been investigated. In addition, intraspecific hybridization between contrasting ecotypes (planktivorous and piscivorous) has been seldom considered in supplementation plans. Here, we combined genetic (genotype-by-sequencing analysis) and life history traits to document the effects of supplementation on maximum length, growth rates, body condition and genetic admixture in stocked populations of two Lake Trout ecotypes from small boreal lakes in Quebec and Ontario, Canada. In both ecotypes, the length of stocked individuals was greater than local individuals and, in planktivorous-stocked populations, most stocked fish exhibited a planktivorous-like growth while 20% of fish exhibited piscivorous-like growth. The body condition index was positively related to the proportion of local genetic background, but this pattern was only observed in stocked planktivorous populations. We conclude that interactions and hybridization between contrasting ecotypes is a risk that could result in deleterious impacts and possible outbreeding depression. We discuss the implications of these findings for supplementation stocking.
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