Cutthroat in the Branches: Spatial Dynamics of Headwater Fish Populations in Managed Forests

Spatial variation in the abundance of aquatic organisms in streams reflects a spatial hierarchy of habitat-forming processes that link stream networks to the landscapes they drain. For example, the characteristics of a stream pool (e.g., pool depth) are determined, in part, by the characteristics of a stream reach (e.g., reach gradient), which are partly determined by characteristics of the stream’s valley (e.g., valley width), and, ultimately, characteristics of the catchment that the stream network drains (e.g., catchment geology, disturbance history).   Here we use a temporal sequence of spatially-continuous data from the South Fork of Hinkle Creek in western Oregon to demonstrate changes in habitat and continuous fish distributions over 11 years and we identify associations among habitat and abundance variables within years and describe how these associations change over time. Our study included periods prior to and following headwater and stream-adjacent logging. We discuss the potential effects of logging on fish and habitat relationships that can be analyzed with this unique data set.