Changes in Lake Sturgeon (Acipenser fulvescens) Habitat in the South Saskatchewan River under Regional Climate Change

Abstract

Climate change effects have been documented in the Canadian Prairie Provinces. Temperature is predicted to continue to increase, and precipitation patterns are changing. As a result, river flow is anticipated to diminish. The South Saskatchewan River (SSR) provides vital habitat to lake sturgeon. Lake sturgeon are currently endangered or threatened across most of their native range, prompting provincial governments to develop management strategies. As lake sturgeon habitat is dependent on flow, understanding climate change impacts on flow conditions in the SSR will be an important component of their long-term management strategy for lake sturgeon. I have developed empirical models based on regional climate variables (temperature and precipitation) to predict in-stream flow. These models were developed using general linear modeling and Akaikes Information Criterion (AIC). Future in-stream flow was predicted by extracting key variables from 5 different GCM’s and inserting the variables into the predictive flow models. These future flow scenarios were coupled with habitat suitability indices developed to assess changes in sturgeon habitat developed by the Water Security Agency and Department of Fisheries and Oceans Canada. Flow scenarios predict a decrease in the habitat of most life stages (spawning, juvenile, adult and subadult), but an increase in fry habitat. These models will represent a novel advancement for sturgeon management in Western Canada.