Breeding Raptor Census in Grand Teton National Park, 2001

We documented abundance and diversity of raptors in a relatively undisturbed landscape in Grand Teton National Park, Wyoming, from February through August 2001. We located a total of 38 nesting pairs / 31.1 km, and a total of 8 raptor species. The American kestrel (Falco sparverius) and the Common raven (Corvus corax) were the two most abundant species on the study area. In this study, we considered Common ravens as an ecological and trophic level equivalent of raptors. Five of the eight species migrate, and two of the eight species are known neotropical migrants. The mean number of young fledged for all species was 1.9 (range=0.2 to 3.1, SD=1.3). We located the territory but not a nest for three Great horned owl (Bubo virginianus) pairs. Low precipitation and warm temperatures characterized weather during the last two years. Effects of weather conditions and human disturbance on raptor abundance within the study area were examined