Winter bald eagle distribution is inversely correlated with human activity along the Colorado River, Arizona
Brown BT and Stevens LE. 1997. Winter bald eagle distribution is inversely correlated with human activity along the Colorado River, Arizona. The Journal of Raptor Research. 31(1):7-10
Helicopter surveys for Bald Eagles (Haliaeetus leucocephalus) were conducted along the Colorado River through Glen Canyon National Recreation Area and Grand Canyon National Park, Arizona, U.S.A. during winter 1990-91. Eagle abundance and distribution were examined for a possible correlation with human activity levels as documented in National Park Service recreational use reports. Twenty-two more eagles were detected in river reaches with low human use compared to river reaches with high to moderate human use. Eagle distribution did not correspond to prey abundance, biomass patterns, or habitat conditions frequently associated with eagle foraging habitat. Moderate to high levels of human activity may have been responsible for lower eagle abundance in some reaches of the river, reinforcing the need for continued management of some areas as refugia where species sensitive to human disturbance can be protected from higher levels of human activity.
- Type
- Journal Article
- Authors
- Brown, Bryan; Stevens, Lawrence
- Units
- GLCA , GRCA
- Keywords
- Abundance (Biodiversity), Arizona, Bald Eagle, Colorado River, Haliaeetus leucocephalus, Human Disturbance, Presence (Biodiversity)