Water Resources Research Act Program

Details for Project ID 2012MT266B

Student Fellowship Project: Evaluating hydrogeomorphic controls on bull trout spawning habitat in mountain streams, Northwestern Montana

Institute: Montana
Year Established: 2012 Start Date: 2012-03-01 End Date: 2013-02-28
Total Federal Funds: $1,000 Total Non-Federal Funds: $420

Principal Investigators: Jared Bean

Abstract: The bull trout (Salvelinus confluentus) is a thermally-sensitive, threatened species, native to the Pacific Northwest, and spawns in the fall in cold-water, gravel-bedded, headwater streams. Effective habitat protection and rehabilitation efforts require understanding the physical and hydrologic processes creating favorable bull trout spawning habitat. At various spatial scales, geomorphology and groundwater conditions are commonly cited as important factors in bull trout spawning site selection and successful fry emergence. However, questions about the interrelation of stream form, process, and habitat suitability remain. This project addresses the following questions: 1) Do bull trout spawn in pool-tail out bedforms of hyporheic downwelling and groundwater upwelling? 2) Are the groundwater flow regimes associated with bounded alluvial valley segments essential to support spawning habitat of these thermally sensitive fish? 3) Do bull trout seek out certain temperature signatures in the stream bed potentially supplied by inflowing groundwater? 4) Are bull trout populations limited by the quantity of suitable spawning habitat?