Cooperative Fish and Wildlife Research Units Program: Wyoming
Education, Research and Technical Assistance for Managing Our Natural Resources

Many of the songbirds that inhabit Wyoming’s forest habitats are demonstrating steep but enigmatic population declines. Declining species include both resident and migratory species, and Wyoming SGCN and non-SGCN. For example, red crossbills declined by an average of 1.7% per year since 1968, and evening grosbeaks were proclaimed one of the fastest declining North American landbirds by Partners in Flight. These declines are part of a larger trend of billions of birds lost in North America since 1970. Considerable attention has been paid recently to similar declines in grassland and sagebrush passerines, whereas no published synthesis exists that codifies trends in western forest birds, or explores the potential mechanisms. This study is conducted in collaboration between the Wyoming Cooperative Fish and Wildlife Research Unit, Wyoming Game and Fish Department and the U.S. Forest Service. We propose to use existing avian monitoring data (BBS, IMBCR, eBIRD) to quantify the population trends in Wyoming’s forest songbirds across different spatial and temporal extents, and explore potential mechanisms underlying population declines and whether multiple stressors may be at play.