Examining Influences on Capture Probability of Migrating Raptors (Poster)

Abstract

Throughout North America, researchers operate annual fall trapping stations to assess patterns, health, and quantities of migrating diurnal raptors. In Montana, Raptor View Research Institute has been trapping diurnal raptors during fall migration along Montana’s Continental Divide since 2004. While we observe over 1,000 raptors migrating each fall, we typically only capture around 150 individuals per season. Examining factors that determine our trapping success would not only provide us with a greater knowledge of these sensitive apex predators but also increase our capture yield. We investigate a variety of temporal, environmental, and species specific variables to determine what factors influence capture probability, including time of year, weather and the age and sex of individual raptors. We share our findings for some of our most frequently caught species, including Golden Eagles, Red‐tailed Hawks, Coopers Hawks, and Sharp‐shinned Hawks, and offer insight into factors that could affect capture rates at migration stations.