Water Resources Research Act Program

Details for Project ID MT_2025_Hudson

Evaluating Effects of Flow on Juvenile Trout Production and Survival in Southwest Montana Watersheds

Institute: Montana
Year Established: 2025 Start Date: 2026-01-01 End Date: 2026-12-31
Total Federal Funds: $2,500 Total Non-Federal Funds: Not available

Principal Investigators: Nicholas Hudson

Project Summary: In the last decade, adult populations of Brown Trout in the Big Hole, Beaverhead, and Ruby rivers of Montana have declined. This decline poses both ecological and economic threats as trout serve as a key food web species and support a robust recreational fishing industry valued at $750 million annually in Montana. Tributaries are often utilized as critical spawning habitat for adults and rearing habitat for juveniles that recruit to main stem populations. Despite their importance, tributaries often receive relatively little monitoring compared to main stem habitats. Flow is a critical environmental variable that significantly influences the life history and demographic patterns of riverine fishes such as Brown Trout. Therefore, there is an urgent need to examine the relationship between flow and trout production and survival in tributaries to deepen our understanding of how flow regulates trout population dynamics in SW Montana rivers.