Integration and Application of Radio Telemetry Data Collected on a Mobile Fish Species: a Synthesis of Bull Trout Movement Research

Bull trout Salvelinus confluentus are a species of char that have been intensively studied since they were listed as threatened under the U. S. Endangered Species Act in 1998. Much of the research on bull trout has involved the use of radio telemetry to monitor the movements of this highly mobile species. This project was initiated to compile information on completed and ongoing radio telemetry studies as a predicate to a synthesis of the state of knowledge about bull trout movement and habitat use. Additionally, predictive models of bull trout post-spawn habitat use were developed in the Boise River, Idaho, a system in which the bull trout population has been intensively studied using radio telemetry. In that system, large, migratory bull trout were distributed throughout the downstream portion of the watershed during winter; however, the most plausible predictive model highlighted the importance of Arrowrock Reservoir as the “hub” of winter habitat use. Field studies based on radio telemetry data can differ in the point of fish capture, the primary method of location, and the sampling intensity. The last section of this report contrasts three studies that differed in these respects highlighting the strengths of each approach. Several important questions about bull trout movement and seasonal distribution remain unanswered. Future telemetry studies should be designed to address specific, testable hypotheses about bull trout movement and habitat use in order to facilitate meta-analytical approaches to developing species-level inferences. Author Matthew R. Dare. Boise State University, 1910 University Drive, Boise, Idaho 837251515. Current address: U.S.D.A. Forest Service, Rocky Mountain Research Station, 322 East Front Street, Suite 401, Boise, Idaho 83702. Phone: 208.373.4371; [email protected].