Availability-Based Resource Selection in Gyrfalcons

Adam Eichenwald

I investigated gyrfalcon predation of rock and willow ptarmigan – its preferred source of food – in Alaska, hypothesizing that the falcon would depredate the most available bird. This was a crucial question to address for future gyrfalcon conservation, as the two species of ptarmigan are affected differently by climate change and the falcon’s future could be tied to the species it preferred. To answer this question, I pulled prey remains from falcon nests over the course of the breeding and nesting season, identifying the ptarmigan species and sex using PCR based methods. I then compared these data to surveys of ptarmigan that I conducted at the same time.