Cooperative Fish and Wildlife Research Units Program: Wyoming
Education, Research and Technical Assistance for Managing Our Natural Resources

Wyoming Project

Determining stream of origin and spawning site fidelity of salmonids in the Upper North Platte River drainage using otolith microchemistry

July 2014 - December 2017


Participating Agencies

  • Wyoming Game and Fish Department
Understanding tributary use of fish in the North Platte River is crucial for successful management of a blue ribbon wild trout fishery.

The Upper North Platte River watershed supports a nationally recognized and important wild trout fishery. The productivity of this fishery is dependent on accessibility to spawning habitat in tributary streams, but we do not know which tributaries are most important for trout spawning. Increasingly, otolith microchemistry analysis is used as a tool to trace fish migrations especially migrations of diadromous fish. In collaboration with the Wyoming Game and Fish Department we built on existing approaches of otolith microchemistry to quantify and compare the migration diversity of two inland salmonid populations, Rainbow Trout (Oncorhynchus mykiss) and Brown Trout (Salmo trutta), residing in the Upper North Platte River Basin. A better understanding of which tributary streams are used by spawning trout is essential for prioritizing management actions to protect this valuable fishery. In addition, this study will improve our understanding of fluvial life-history strategies of trout and the physical characteristics of important spawning tributaries.