Habitat Studies at Morley Nelson Snake River Birds of Prey National Conservation Area
Morley Nelson Snake River Birds of Prey National Conservation Area
A golden eagle soaring above the desert plateau in Morley Nelson Snake River Birds of Prey National Conservation Area (NCA) swoops with speed and agility using its sharp talons to snatch up a black-tailed jackrabbit, the raptor’s major prey. The unique combination of climate, geology, soils and vegetation of the Snake River ecosystem supports extraordinary numbers of prey and the most significant aggregation of nesting raptors in North America and perhaps the World.

Michael Kochert of the U.S. Geological Survey in Boise and Karen Steenhof of the Owyhee Desert Studies in Murphy, Idaho, presented the latest research on responses of nesting raptors to habitat alteration in the NCA during A Decade of Discovery, a science symposium celebrating the 10th anniversary of the BLM’s National Landscape Conservation System, in Albuquerque, New Mexico, May 24 - 28. The event was sponsored by the BLM in partnership with the New Mexico Museum of Natural History and Science.

Located 35 miles south of Boise, Idaho, the NCA supports more than 700 raptor pairs, representing 16 species that nest on the high canyon walls each spring, with 8 additional species seasonally migrating through the area. However, over the past 30 years, recurring wildfire, land uses and drought have been causing extensive habitat changes. 


Michael Kochert, scientist emeritus with the U.S. Geological Survey in Boise, said, “Preliminary results of monitoring and research suggest that while some raptor species, particularly those on the plateau, have been fairly resilient to the changes, Golden Eagles and Prairie Falcons have been less resilient."
 
Since 1980, thousands of acres of the NCA's big sagebrush and salt desert shrub habitat have burned and been replaced with exotic annual grasses and weeds, particularly cheatgrass. This landscape-scale change to annual grassland has caused jackrabbit populations to plummet and ground squirrel populations to destabilize.

Early research results indicate a significant negative trend for the number of Golden Eagle pairs in the NCA, with a 30 percent decline between 1971 and 2009, according to Kochert. “Although various human uses have affected raptor populations, the loss of native plant communities, spread of annual weeds and the escalating fire cycle probably have had the most significant and profound influence.”

Conservation actions in the NCA include wildfire suppression and restoration of native shrubs and perennial grasses within Golden Eagle and Prairie Falcon foraging areas, as well as subsequent monitoring.

To learn more about Morley Nelson Snake River Birds of Prey National Conservation Area , please click here.

To read more features and learn more about A Decade of Discovery Science Symposium, please click here.


Golden Eagle at Morley Nelson Snake River Birds of Prey NCA
Golden Eagle at Morley Nelson Snake River Birds of Prey NCA
Prairie Falcon Chicks at Morley Nelson Snake River Birds of Prey NCA
Prairie Falcon Chicks at Morley Nelson Snake River Birds of Prey NCA