The best long-term survey for Western Grebe is the Christmas Bird Count (CBC). CBC results from both Canada and North America show large decreases in the wintering population relative to 1970. The British Columbia Coastal Waterbird Survey also shows an important drop in that region since 1999, and nesting populations in Alberta have also decreased in size (Yanch et al. 2006), although they may be larger than previously thought (Prescott et al. 2018). However, given that a possible southward shift in wintering distribution may impact regional CBC trends (Anderson et al. 2011), and search effort may vary among years (Yanch et al. 2006), the large decrease status has been assigned medium reliability. Note that although Western and Clark’s Grebe are combined in CBC counts, Clark’s Grebes are very rare and thus unlikely to bias trend estimates. The Western Grebe is currently below the lowest acceptable level relative to its national population goal, which is based on the CBC (see North America graph below). Once the Management Plan is developed under the Species at Risk Act, this goal will be re-examined.
Additional information on: Christmas Bird Count (CBC)
Additional information on: British Columbia Coastal Waterbird Survey
