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S.R. Phelps

Publications and source records attributed to S.R. Phelps.

8 recordsLinked to original sources

Genetic variation in steelhead ( Salmo gairdneri ) from the north coast of Washington

Steelhead ( Salmo gairdneri ) collected from various sites in nine drainages in northwestern Washington were genetically characterized at 65 protein-coding loci by starch-gel electrophoresis. Genetic differentiation within and among drainages was not significant, and genetic variation among drainages was much less than that reported in British Columbia; these results may be the consequence of gene flow from hatchery stocks that have been released in Washington since the 1940's. Allele frequencies varied significantly among year-classes (hence, genetic characterization studies must include data from several year-classes), and also between hatchery fish (including a stock developed with local wild fish) and wild fish, indicating that few wild fish have been successfully and routinely included in hatchery brood stocks. Conservation of genetic diversity along the north coast of Washington should be facilitated by reducing the numbers of hatchery fish that spawn in streams and by including wild fish in hatchery brood stocks.

Washington

Basis for managing the harvest of Chinook salmon

On the basis of estimated spawner-recruit relations for populations of chinook salmon Oncorhynchus tshawytscha from British Columbia to California, harvest fractions of 60-70% may be reasonable for stocks for which the productivities are not known. Care should be taken to detect and to avoid excessive harvest from stocks with low productivity.

North American Journal of Fisheries Management

Genetic variation in chinook, Oncorhynchus tshawytscha , and coho, O. Kisutch</i?, salmon from the north coast of Washington

We used starch-gel electrophoresis to genetically characterize the populations of chinook salmon, Oncorhynchus tshawytscha, and coho salmon, O. kisutch, in the major drainages of the north coast of Washington (the Quillayute, Uoh, Queets, and Quinault Rivers). Of 55 loci examined for electrophoretically detectable variation. 6 were polymorphic (frequency of the common allele was less than 0.95) in chinook salmon and 3 in coho salmon. Statistical tests of interdrainage and intradrainage variation for coho salmon were tenuous because most of the fish examined were from a single year class so that we could not account for variation among year classes. Nevertheless, these tests suggested that distinct stocks ofcoho salmon exist within drainages. and that variation was not significantly greater among drainages than within drainages. Interdrainage variation for wild chinook salmon was not significant. The data suggested that summer chinook salmon were electrophoretically different from fall chinook salmon, and the hatchery populations of chinook salmon were distinct from wild fish. A hatchery population developed primarily from north coast fish was electrophoretically more similar to wild chinook salmon than were the others.

Washington

Fish cell lines: Characterization by isozyme analysis

The electrophoretic mobilities of isozymes from 16 enzyme systems were determined for nine fish cell lines. The relative migration of the malate dehydrogenase and 6-phosphoglucose dehydrogenase isozymes could be used together to distinguish between seven of the fish cell lines. Two cyprinid cell lines could not be distinguished from each other but were readily separated from the six noncyprinid lines and the one other line of cyprinid origin.

In Vitro

Multilocus electrophoretic assessment of the genetic structure and diversity of Yersinia ruckeri

Multilocus isoenzyme electrophoresis was used to screen 47 field isolates of Yersinia ruckeri for electrophoretic variation at 15 enzyme loci. Only four electrophoretic types were observed, thus indicating that the genetic structure of Y. ruckeri is clonal. Forty-two isolates were of one electrophoretic type, a reflection of the low amount of genetic diversity extant in this species. Although sorbitol fermentation has been considered to be indicative of a second biotype, no significant gene frequency differences were found between the group of 20 isolates that readily used sorbitol as the sole carbon source and the group of 27 that did not.

Applied and Environmental Microbiology