Sooty Grouse – Booming on Burnaby Mountain

A displaying Sooty Grouse booming, which echoed across Burnaby Mountain as we watched. A male stood under the fir tree with his bright yellow air sacs fully inflated giving us a show. Expandable neck sacs inflate during the breeding season to amplify the grouse’s low-frequency calls, helping attract females and establish territory. The bird repeatedly extending the sacs while producing its distinctive booming display, a behavior most commonly seen during spring. Sooty Grouse are year-round residents of British Columbia’s coastal forests. They are often easier to hear than see during the breeding season. This memorable encounter highlighted one of the Pacific Northwest’s most unique courtship displays.