Graduate student kayaking at Glacier National Park researching bull trout
This project is designed to assess the feasibility of "rescuing" specific genetic lineages of bull trout from likely extirpation in three imperiled major lake drainages in GNP, through translocation of drainage-specific stocks into lakes located above barrier falls within parental drainages. The long-term goal for these populations is to maintain self-sustaining bull trout populations upstream within their natal drainages to avoid the loss of the unique genetic and life-history adaptations. Since GNP supports a significant proportion of the remaining natural lake habitat within the range of bull trout, this project also has range-wide implications for the species. The specific objectives are to: 1. Capitalize on status information from the previous SSP research on distribution, abundance, and genetic diversity of bull trout populations in Arrow, Trout, Bowman, and Logging lakes (herein referred to as potential donor populations) to determine their suitability as donor populations; 2. Evaluate the suitability of spawning, rearing, foraging, overwintering habitats, and aquatic biota (fish, plankton, zooplankton, and macroinvertebrates) in isolated (above natural barriers to fish migration) headwater lakes (e.g., Pocket, Grace, and Ellen Wilson) and the concomitant tributaries (herein referred to as potential recipient areas) of recipient lakes. Climate change models will also be employed to examine long-term habitat suitability; 3. Prioritize and plan the translocation strategy for bull trout within drainages where feasible, by identifying biological and environmental factors that may limit population growth and persistence.
USGS Montana Fishery Research Unit, public domain