IDFG To Monitor Bull Trout

The Idaho Department of Fish and Game and University of Idaho personnel are using radio transmitters and fishing gear to track the migration patterns of bull trout in the North Fork Clearwater River drainage. Funded by the IDFG and the Clearwater National Forest, the information collected will help fisheries managers determine migration timing and ensure identification of critical habitat utilized by the resident trout. Ultimately, this information will help protect and recover the bull trout populations within the drainage. If improvements are made, Endangered Species Act listing and the restrictions it places on human activities could be avoided. Although bull trout have been observed and collected throughout the drainage, little information is available on their life history, distribution and abundance. More importantly, no information is available regarding the role of Dworshak Reservoir in the life history and distribution of bull trout in the drainage. Fisheries managers, believe this study will answer many of the unknowns. IDFG started the two-year study last spring when they captured 59 bull trout by hook-and-line in the North Fork arm of Dworshak Reservoir. They surgically implanted 21 of the fish with radio transmitters, released them, then documented their movements throughout the year. This year, IDFG is expanding the study into the Little North Fork Clearwater River drainage where an additional 90 trout are to be captured. Another important component of the study is to estimate the cutthroat and bull trout populations and the fishing pressure on Fish Lake, a high mountain lake in the drainage. Little information is available on the basic life history of this population. Also, the role Fish Lake and its bull trout population play in the dynamics within the river drainage is unknown. Beginning July 6th and continuing until October, IDFG will be using a variety of methods to tag trout in the lake. IDFG also plans to interview anglers during the season which opens August 1. According to IDFG biologists, the presence of bull trout in these waters indicates healthy conditions for other species as well. The habitat needs of bull trout overlap those of many other trout species, so working to reduce and reverse threats to their survival will ultimately benefit other Idaho fish species. Native to the Pacific Northwest, including Montana, Idaho, and northern California and Nevada, the bull trout has some of the most demanding habitat requirements of any native trout species, mainly because it requires water that is especially cold and clean. Abundant a century ago dams, siltation from logging and farming, and fishing pressure has greatly reduced its numbers and range.