State Water Resources Research Institute Program
Project ID: 2012MT266B
Title: Student Fellowship Project: Evaluating hydrogeomorphic controls on bull trout spawning habitat in mountain streams, Northwestern Montana
Project Type: Research
Start Date: 3/01/2012
End Date: 2/28/2013
Congressional District: at large
Focus Categories: Ecology, Geomorphological Processes
Keywords: trout, geomorphology
Principal Investigator: Bean, Jared
Federal Funds: $ 1,000
Non-Federal Matching Funds: $ 420
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?