Spatial Variability of Chinook Salmon Spawning Distribution and Habitat Preferences
A wide range of environmental conditions can affect Pacific salmon’s habitat selection and spawning distribution. Understanding how habitat selection occurs at different spatial scales and how consistent spawning distributions are over time is important for predicting salmon population trends. Researchers investigated physical habitat conditions associated with chinook salmon spawning sites and examined the interannual consistency of spawning distribution across multiple spatial scales in the upper Yakima River in Washington. Interannual reoccupation of spawning areas was high and most consistent in large-scale river reaches compared to smaller channel units and subunits, such as individual pools. At reach scales, models showed that stream power and depth were the primary predictors of redd abundance, while at smaller scales, habitat at the downstream end of pools and thermal variability were important predictors of spawning. Understanding chinook salmon spawning habitat preferences and their reoccupation of spawning areas at different spatial scales can inform management actions for salmon conservation.
Cram, J.M., Torgersen, C.E., Klett, R.S., Pess, G.R., May, D., Pearsons, T.N., Dittman, A.H., 2017, Spatial variability of Chinook Salmon interannual spawning distribution and habitat preferences: Transactions of the American Fisheries Society, v. 146, no. 2, p. 206-221, http://dx.doi.org/10.1080/00028487.2016.1254112. [Details]