Raptor Use of the Rio Grande Gorge

Ponton, David A.¹ 

[1] Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

关键词: Basic Biological Sciences(59);    Environmental Sciences(54) Biological Science;    raptor;    bird of prey;    Rio Grande Gorge;    New Mexico;    red-tailed hawk;    golden eagle;    prairie falcon;    peregrine falcon;    bald eagle;    canyon;    river;    river running;    nesting;    cliff;    Bureau of Land Management;   

DOI  :  10.2172/1209319
RP-ID  :  LA-UR--15-22044
PID  :  OSTI ID: 1209319

美国|英语

来源: SciTech Connect

【 摘 要 】

The Rio Grande Gorge is a 115 km long river canyon located in Southern Colorado (15 km) and Northern New Mexico (100 km). The majority of the canyon is under the administration of the Bureau of Land Management {BLM), and 77 km of the canyon south of the Colorado/New Mexico border are designated Wild River under the National Wild and Scenic Rivers Act of 1968. Visits I have made to the Rio Grande Gorge over the past 15 .years disclosed some raptor utilization. As the Snake River Birds of Prey Natural Area gained publicity, its similarity to the Rio Grande Gorge became obvious, and I was intrigued by the possibility of a high raptor nesting density in the Gorge. A survey in 1979 of 20 km of the northern end of the canyon revealed a moderately high density of red-tailed hawks and prairie falcons. With the encouragement of that partial survey, and a need to assess the impact of river-running on nesting birds of prey, I made a more comprehensive survey in 1980. The results of my surveys, along with those of a 1978 helicopter survey by the BLM, are presented in this report, as well as general characterization of the area, winter use by raptors, and an assessment of factors influencing the raptor population.