Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves [86-108]). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Thesis (Ph. D.)--Oregon State University, 1996. / Typescript (photocopy). Includes bibliographical references. Also available online.

Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 42-47). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [185]-208).

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 57-68). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 47-55). Also available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 53-61). Also available on the World Wide Web.

Thesis (M.E.S.)--The Evergreen State College, 2008. / Title from title screen (viewed 2/25/2009). Includes bibliographical references (leaves 32-33).

This research focused on features of a genetically isolated population of cutthroat trout (Oncorhynchus clarki) in the Triangle Lake basin of coastal Oregon. A falls at the outlet of Triangle Lake has blocked upstream migration of trout and anadromous salmonids into the basin. Cutthroat trout were found throughout the six study streams of the Triangle Lake basin in association with other native fishes and introduced warmwater fishes. Warmwater species (e.g. Centrarchidae) were restricted largely to the lakes of Triangle Lake basin, and did not comprise a significant part of the stream fish fauna. Salmonids and cottids dominated the upper forested reaches of the basin, whereas nonsalmonids dominated the lower reaches. The middle reaches contained a transitional fish community between the upper and lower reaches. Reach type was a major factor influencing cutthroat trout density and size distribution. Areal densities of cutthroat trout were highest in the upper reaches and lowest in the lower reaches with the exception of 0+ cutthroat trout, which occurred at similar densities in all reaches. The highest frequency of 1+ cutthroat trout occurred in the middle reaches, whereas the highest frequency of 0+ cutthroat occurred in the lower reaches. Within reaches, channel unit type influenced the density and age structure of cutthroat trout. Pools and rapids had the highest densities of cutthroat trout, whereas riffles, glides, and cascades had lower densities. Larger trout were found primarily in pools and rapids. Planted steelhead fry (Oncorhynchus mykiss) were found in two streams, Congdon Creek and Lake Creek. Although most steelhead fry leave the basin as smolts, some steelhead appear to become resident and may hybridize with native cutthroat trout. Cutthroat trout spawning was observed from late December 1987 through late May 1988. Differences in the time and place of spawning may serve to genetically isolate two populations of cutthroat trout in Triangle Lake basin. One population may be lake dwelling as adults and spawn lower in the basin in late spring. The other population may be stream dwelling and spawn in the winter during higher flows, which allows them to spawn in the upper reaches of the basin. / Graduation date: 1994