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Objective: The Clark Fork–Pend Oreille River basin of northeastern Washington and the Idaho Panhandle historically supported a robust metapopulation of the Westslope Cutthroat Trout (WCT) Oncorhynchus lewisi, a western native salmonid of high cultural and economic value. The construction of impassible hydroelectric dams and smaller instream barriers has prevented the return of migratory WCT to spawning tributaries, leading to the fragmentation of this metapopulation over the past 100 years. One such impassible barrier is Albeni Falls Dam (AFD) near Newport, Washington, which was completed without fish passage capabilities in 1955. We sought to examine large‐scale genetic patterns in the study area and determine the most likely spawning tributary of origin for migratory WCT captured below AFD. Methods: We created a genetic baseline representative of populations within the Clark Fork–Pend Oreille River basin from upstream and downstream of the dam using 191 biallelic single‐nucleotide polymorphism genetic markers. Our data set included 124 collections, which allowed for an examination of population structure and hatchery influence across the study area and provided a robust tool for population assignment. Population assignment tests were conducted using the program RUBIAS. Result: Population assignment tests were successful for all pure WCT of unknown origin despite potential influence from hatchery lineages across the study area. Of 83 migratory WCT captured below AFD, approximately 80% were assigned to tributaries upstream of AFD with a posterior assignment probability of at least 90%. Only one fish was assigned to a tributary downstream of AFD. Conclusion: Our results indicate that AFD disrupts the natural metapopulation dynamics of WCT populations in the basin. Passage for WCT at this barrier would reestablish metapopulation connectivity within the basin by allowing migratory individuals to make genetic contributions to populations upstream of the dam. Impact statementMost Westslope Cutthroat Trout captured below Albeni Falls Dam were genetically assigned to regions upstream of the dam, indicating that this barrier disrupts their natural metapopulation structure. Fish passage facilities would likely benefit these salmonids. [ABSTRACT FROM AUTHOR]

In supplementation programs, hatcheries employ wild-origin fish as brood stock and their offspring are allowed into wild spawning areas. Resource managers use supplementation to support imperiled salmonid populations, seeking to increase census size and possibly effective population size ([N.sub.e]), while minimizing risks of genetic diversity loss and domestication from hatchery intervention. Here we document impacts of 5-10 years of supplementation on threatened summer-run chum salmon (Oncorhynchus keta) in Hood Canal (HC) and Strait of Juan de Fuca (SJF) in Washington State and compare them genetically with unsupplemented summer- and fall-run chum salmon from HC and South Puget Sound. Microsatellite allele frequencies identified four run-timing and geographic groups. HC and SJF summer chum salmon genetic relationships followed a metapopulation pattern of isolation by distance, similar to patterns prior to supplementation, suggesting that supplementation minimally impacted population structure. In most supplemented subpopulations, we detected no effects on diversity and [N.sub.e], but high variance in individual pairwise relatedness values indicated over-representation of family groups. In two subpopulations, hatchery impacts (decreased diversity and lower [N.sub.e]) were confounded with extreme bottlenecks. Rebounds in census sizes in all subpopulations suggest that general survivorship has improved and that possible hatchery effects on genetic diversity will be overcome. Dans les programmes de supplementation, les piscicultures utilisent des poissons d'origine sauvage comme stock reproducteur et les rejetons sont introduits dans des zones sauvages de fraie. Les gestionnaires des ressources utilisent la supplementation pour soutenir les populations menacees de salmonides, cherchant ainsi a augmenter la taille de la population recensee et, si possible, la taille effective de la population ([N.sub.e]), tout en minimisant les risques de perte de la diversite genetique et de domestication dus a l'intervention en pisciculture. Nous etudions ici les impacts de la supplementation pendant 5-10 ans sur des saumons keta (Oncorhynchus keta) a montaison estivale menaces dans le canal de Hood (HC) et le detroit de Juan de Fuca (SJF) dans l'etat de Washington; nous comparons genetiquement ces saumons a des saumons a montaisons estivale et automnale, mais sans supplementation, de HC et de Puget Sound. Les frequences des alleles des micro-satellites mettent en evidence quatre groupes d'apres le moment de la montaison et l'origine geographique. Les relations genetiques des saumons keta d'ete de HC et de SJF montrent un patron de metapopulation par isolement par la distance, semblable au patron trouve avant la supplementation, ce qui indique que la supplementation a un impact minimal sur la structure de la population. Dans la plupart des sous-populations ayant connu la supplementation, nous ne decelons aucun effet sur la diversite ni sur Ne, mais il y a une forte variance des valeurs appariees de parente qui indique une surrepre sentation des groupes familiaux. Dans deux sous-populations, les impacts de pisciculture (diversite et [N.sub.e] reduites) se confondent avec des goulots d'etranglement extremes. Des remontees dans les tailles recensees des sous-populations laissent croire que la survie generale s'est amelioree et que les effets possibles de pisciculture sur la diversite genetique seront surmontes. [Traduit par la Redaction], Introduction Fisheries managers are shifting towards supportive breeding or supplementation hatcheries as a means to boost population abundance in threatened populations while minimizing risks from domestication (Ford 2002; Goodman 2004). [...]

Genetic structure and relationships in the intertidal snail species complex Littorina arcana Hannaford Ellis, L. compressa Jeffreys and L. saxatilis (Olivi) have been studied from samples from six locations the British Isles. Single-strand conformational polymorphisms (SSCPs) of cytochrome-b fragments were used. It appears that Pleistocene sea level changes explain the congruent genetic patterns.

Conservation of threatened and endangered species often involves large‐scale collaboration across jurisdictional boundaries, but such efforts are typically hampered by a lack of consistent monitoring data at local, regional, and species‐distributional scales. Contemporary methods of genetic monitoring that are grounded in sequencing‐based approaches offer a powerful means to achieve the data consistency necessary for conservation of high‐profile species. Here, we describe the collaborative, multiagency development of a genotyping‐in‐thousands by sequencing panel for genetic monitoring of threatened Bull Trout Salvelinus confluentus across its range in North America. The resulting panel consists of 266 single nucleotide polymorphisms, a subset of which differentiate Salvelinus species (Arctic Char S. alpinus, Brook Trout S. fontinalis, Bull Trout, Dolly Varden S. malma, Lake Trout S. namaycush, and Whitespotted Char S. leucomaenis), as well as one sex ID locus. We then used case studies from the Pacific Northwest and northern Rocky Mountains to demonstrate the efficacy of the panel for addressing local conservation needs (e.g., genetic variation, genetic differentiation, genetic assignment tests, and number of effective breeders) and compatibility with legacy data sets. Future genotyping with this panel will provide opportunities for improved conservation prioritization across the species range and collaboration among the numerous agencies charged with conserving this species. This effort provides framework to develop population genetic tools that will contribute to robust and efficient monitoring of biodiversity. [ABSTRACT FROM AUTHOR]

Abstract--Microsatellite DNA analysis was applied in a genetic study of 20 chinook salmon populations from four regions within the Fraser River drainage of British Columbia, Canada. Twelve populations were represented [...]

Programs to rebuild imperiled wild fish populations often include hatchery-born fish derived from wild populations to supplement natural spawner abundance. These programs require monitoring to determine their demographic, biological, and genetic effects. In 1990s in Washington State, the Summer Chum Salmon Conservation Initiative developed a recovery program for the threatened Hood Canal summer chum salmon Evolutionarily Significant Unit (ESU) (the metapopulation) that used in-river spawners (wild fish) for each respective supplementation broodstock in six tributaries. Returning spawners (wild-born and hatchery-born) composed subsequent broodstocks, and tributary-specific supplementation was limited to three generations. We assessed impacts of the programs on neutral genetic diversity in this metapopulation using 16 microsatellite loci and a thirty-year dataset spanning before and after supplementation, roughly eight generations. Following supplementation, differentiation among subpopulations decreased (but not significantly) and isolation by distance patterns remained unchanged. There was no decline in genetic diversity in wild-born fish, but hatchery-born fish sampled in the same spawning areas had significantly lower genetic diversity and unequal family representation. Despite potential for negative effects from supplementation programs, few were detected in wild-born fish. We hypothesize that chum salmon natural history makes them less vulnerable to negative impacts from hatchery supplementation. [ABSTRACT FROM AUTHOR]

Abstract American marten (Martes americana ) have a close association with mature temperate forests, a habitat that expanded throughout the Pacific Northwest as glaciers receded at the end of the Pleistocene. Similar to several other forest-associated mammals in North America (e.g. black bear), genetic analysis of the marten shows a deep phylogeographical subdivision that reflects populations with distinctive evolutionary histories. Using a suite of 14 microsatellite markers, we explored the genetic structure of marten populations in two reciprocally monophyletic clades in the Pacific Northwest identified previously as M. caurina and M. americana by mitochondrial haplotypes and morphology. Microsatellite phylogeographical patterns were congruent with mitochondrial analyses. These independent data sets shed light upon hybridization patterns, population structure and evolutionary histories. Hybridization between M. caurina and M. americana individuals was documented in two regions of sympatry (Kuiu Island in southeastern Alaska and southern Montana). Northern insular populations of M. caurina exhibited higher differentiation and lower variability relative to northern populations of M. americana . Greater divergence among M. caurina populations may reflect longer isolation and persistence in coastal forest habitat that was fragmented by rising sea level in the early Holocene. Lower differentiation among northern M. americana populations and close relationship to other continental M. americana populations may reflect more recent expansion into the Pacific Northwest and/or continued gene flow among populations. Differentiation among M. caurina populations was attributed to habitat fragmentation (i.e. rising sea level), as opposed to isolation-by-distance; oceanic straits pose significant barriers to gene flow among M. caurina populations and between populations of M. caurina and M. americana . [ABSTRACT FROM AUTHOR]

Snails of the Littorina saxatilis species complex are ubiquitous and important members of hard shore intertidal communities in the North Atlantic. The complex includes L. arcana, L. compressa and L. saxatilis. We investigated species and population structure among these species from six locations in Ireland and Britain using a nonradioactive single strand conformational polymorphism analysis of a 375 base pair fragment of the cytochrome-b gene. Variability was high with 38 haplotypes found in 591 individuals. The most common haplotype in L. arcana and L. compressa was absent from L. saxatilis and the most common haplotype in L. saxatilis was found in low numbers in L. arcana and L. compressa. Haplotypes restricted to L. arcana and L. compressa formed a cluster separate from L. saxatilis haplotypes in maximum parsimony and multidimensional scaling analyses. In analyses examining populations, L. arcana and L. compressa formed a group separate from L. saxatilis. Both the populations in the L. arcana/L. compressa group and in L. saxatilis show similar geographical structuring in that the North England populations were separated from a cluster of Cornwall (South-west England) and Irish populations. We suggested that Pleistocene sea level changes accounted for these congruent genetic patterns. We concluded that L. arcana and L. compressa are more closely related to each other than either is to L. saxatilis and offer this as a resolution to a previous trichotomy. [ABSTRACT FROM AUTHOR]