Record Details
Field | Value |
---|---|
Title | A population study of the rainbow trout (Salmo gairdneri) in a Central Oregon stream |
Names |
Osborn, Charles Edwin
(creator) Hall, James D. (advisor) |
Date Issued | 1967-06-07 (iso8601) |
Note | Graduation date: 1968 |
Abstract | The rainbow trout population in Elder Creek, Oregon was studied between June 1965 and November 1966. The physical characteristics of the stream during the summer season were described. Rainbow trout were captured in each of three sections on the stream by electrofishing and were tagged and measured. Population size, mortality, recruitment, growth rate, and production was estimated for fish in each section where data were sufficient. Estimates were made of the yield of trout to the sport fishery. The water in Elder Creek is relatively low in concentration of dissolved solids. The stream lies in a canyon of mostly bedrock and large cobbles with very little spawning gravel. Water temperature was found to be near the maximum for trout suitability in the lower reaches of the stream. Reliable estimates of population size and their variation were obtained within the summer of 1966. Population size estimates for the summer of 1965 were not reliable because of the small numbers of trout that could be obtained during this period. Therefore estimates of annual rates of mortality, growth, and production were not possible, Growth rates were estimated for marked and for unmarked fish during the summer of 1966. Marked fish were found to have a markedly lower growth than unmarked fish. Of 755 observations of trout movement during the study less than four percent were found to have moved more than 300 feet. Immigration of adult fish into the population was either insignificant or not detectable. Although Elder Creek has a good population of legal-sized native trout, fishing pressure on the stream is relatively light. The lower reaches are fished more heavily than the headwaters, which probably receive no angling pressure during some fishing seasons. |
Genre | Thesis/Dissertation |
Topic | Rainbow trout |
Identifier | http://hdl.handle.net/1957/22293 |