Evaluating the use of redd counts in monitoring Snake River Cutthroat in Snake River tributaries
July 2018 - June 2021
- Jacksone Hole One Fly
- Wyoming Game & Fish Department
Redd counts are a commonly used management tool for monitoring spawning salmonid population status and trends. The validity of redd count data as an index of population size is based on two key assumptions: 1. redd counts are representative of actual redd numbers and 2. redd counts reflect population status. These may not always be met, especially when there is substantial red superimposition, leading to biased redd counts. In conjunction with Wyoming Game and Fish Department we are evaluating the relationships between redd count data and spawning populations, spawning success, and fry emergence in spring creeks in the Upper Snake River drainage. The results of this project will allow managers to better interpret what redd counts can tell us with respect to population status (spawner numbers, fry production). This will allow for recommendations on how to most effectively conduct redd counts moving forward.