Susan M. Pollard

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An understanding of the relative roles of historical and contemporary factors in structuring genetic variation is a fundamental, but understudied aspect of geographic variation. We examined geographic variation in microsatellite DNA allele frequencies in bull trout (Salvelinus confluentus, Salmonidae) to test hypotheses concerning the relative roles of(More)
Bull trout, Salvelinus confluentus (Salmonidae), are distributed in northwestern North America from Nevada to Yukon Territory, largely in interior drainages. The species is of conservation concern owing to declines in abundance, particularly in southern portions of its range. To investigate phylogenetic structure within bull trout that might form the basis(More)
Population structure and the application to genetic stock identification for steelhead (Oncorhynchus mykiss) in the Nass and Skeena Rivers in northern British Columbia was examined using microsatellite markers. Variation at 8 microsatellite loci (Oki200, Omy77, Ots1, Ots3, Ssa85, Ots100, Ots103, and Ots108) was surveyed for approximately 930 steelhead from(More)
Steelhead trout, Oncorhynchus mykiss (the anadromous form of rainbow trout), are declining over much of their range around the Pacific rim. We nondestructively collected tissue samples from 494 adult steelhead from eight tributaries and two mainstem river sites within three watersheds in northern British Columbia, Canada. We scored allele size for six(More)
Okanagan Lake, south-central interior of BC, contains two reproductive ecotypes of kokanee Oncorhynchus nerka; individuals spawn in tributary streams ('stream-spawners') as well as on shoreline gravel areas ('beach-spawners'). We tested the hypothesis that these sympatric ecotypes comprise a single panmictic population by assaying variation in morphological(More)
Partitioning within-species genetic diversity is fundamental to conservation of the bioheritage, current viability, and evolutionary potential of individual taxa. We conducted a hierarchical analysis of genetic diversity in Dolly Varden (Salvelinus malma) and bull trout (Salvelinus confluentus) involving analysis of hybrid zones between Dolly Varden and(More)
Kokanee are the nonanadromous (freshwater resident) form of sockeyesalmon (Oncorhynchus nerka) found in lake ecosystems throughoutthe North Pacific region. Kokanee commonly exhibit two reproductiveecotypes; `stream-spawners' that reproduce in streams tributary tolakes, and `beach-spawners' that reproduce on submerged lakeshore gravelbeaches. Okanagan Lake,(More)
Two reproductive types of kokanee are found in Okanagan Lake, British Columbia: one form that spawns in streams, and another that spawns approximately 2–4 weeks later along beaches of the lake. We examined the levels and patterns of genetic and morphometric variation among three populations (1 beach and 2 stream populations) to better understand life(More)
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