The History and Current Status and Distribution of Beavers in Yellowstone National Park

Beaver populations in Yellowstone National Park (YNP) have exhibited significant fluctuations over nearly a century, with a notable decline followed by recovery. Research analyzing surveys conducted from the 1920s to the 2000s reveals that beavers were abundant in the northern range during the early surveys but declined by 1953, with no active colonies at previously recorded sites and reduced willow use. Subsequent aerial surveys from 1996 to 2009 documented a rising trend in active colonies, peaking at 127 in 2007, likely due to willow recovery. This study provides critical insights into the ecological dynamics of beavers as keystone species in YNP, highlighting their role in vegetation and ecosystem shaping.

Smith, D. W., & Tyers, D. B. (2012). The History and Current Status and Distribution of Beavers in Yellowstone National Park. Northwest Science, 86(4), 276. https://doi.org/10.3955/046.086.0404