Kakwa River Watershed, Arctic Grayling Assessment 2016 – 2017
Scott Seward and Brad Hurkett
We sampled 117 sites in the Kakwa River watershed using angling gear in July and August, 2016/17. Arctic grayling were detected throughout the downstream three quarters of the watershed, but not in the upstream quarter of the watershed. Specifically, no Arctic grayling were captured above South Kakwa Falls, Francis Peak Creek Falls or the Lower Kakwa Falls despite the presence of suitable Arctic grayling habitat.
Both juvenile and adult Arctic grayling abundance in the Kakwa River watershed is low. There was no evidence of missing size classes within the length distributions of captured Arctic grayling. The highest catch rates for adult Arctic grayling were in sixth- and seventh-order streams, while fifth-order streams had the highest catch rates for juvenile Arctic grayling.
Our study provides current data on the abundance, distribution and population structure of Arctic grayling within the Kakwa River watershed, a FSI priority species for AEP. This information is useful to land managers seeking to balance the diverse values of the land base upon which they operate and critical for the conservation of native fish species particularly sensitive to habitat degradation and overfishing, such as Arctic grayling. The data collected in this study will aid in the development of an Arctic grayling FSI rank for the Kakwa River watershed and support regulatory actions to remediate the effects of industrial activities on Arctic grayling populations and their habitats.