Golden Eagle (Aquila chrysaetos) 



Distribution: Breeds in North America at high latitudes from Alaska to Labrador south to Baja 

 California and west Texas. Common and widespread breeding bird in Montana (Bergeron et 

 al. 1992) and South Dakota (S.D. Omithol. Union 1991). Winters throughout the breeding 

 range and into the eastern United States. 



Habitat Use: Occurs in most habitats in the western states, from desert grasslands to above 

 treeline in the mountains, possibly avoiding only dense forest where hunting would be 

 difficult. During summer, it is often associated with outcrops and a dependable food supply. 

 Primary foods from Carter County nests (Becker 1978) were white-tailed jackrabbits, 

 white-tailed or mule deer fawns, cottontail rabbits, pronghom fawns, £ind white-tailed prairie 

 dogs. Along the Tongue River in northern Wyoming and southeastern Montana, prairie dogs 

 and cottontail rabbits represented 80% of the prey biomass at 4 nests (Phillips et al. 1990). 



Nest Sites: Prefers to nest on cliffs or large trees. Of 42 active and inactive nest sites in 1977-78 

 in Carter County (Becker 1978, pers. comm.), 76% were on cliff walls (12.0 ± 6.5 m above 

 ground) and 24% in trees (1 1.1 ± 3.1 m above ground); near Livingston, Montana 62% of 92 

 nests were on cliffs, 2% on the ground, and the remainder in trees (McGahan 1968); in 

 northeastern Wyoming 86% of 170 nests were in trees (13.4 ± 2.5 m above ground) 

 (Menkens and Anderson 1987); elsewhere in northeastern Wyoming, 82% of nests were in 

 trees (2/3 in deciduous, 1/3 in ponderosa pine), 8% on rock outcrops, 7% on man-made 

 structures, and 3% in creek banks (Phillips and Beske 1990). Nest-site choice appears to 

 depend on site availability. Golden Eagles will build several nests on a single territory, and 

 rotate use of these over several years. Orientation of nests may be temperature dependent; 

 over half of the nests in Montana faced south to west (McGahan 1968, Becker 1978). Will 

 use artificial platforms (Phillips and Beske 1990). S.D. Natural Heritage Program EO's 

 provided 5 nest records from the South Cave Hills, 5 from the North Cave Hills, 4 from the 

 East Short Pine Hills, and 36 from Slim Buttes between 1974-89; 34% of nests were active 

 in more than one year. Nests are larger and bulkier than Buteo nests (Call 1978). 



Nest Success: Usually lays 2-3 eggs. Young/nest was 1.43 for 67 active nests between 1974-89 

 in Harding County, South Dakota units of the Sioux District (Appendix 3); 40 nests 

 contained 1 young, 25 nests contained 2, and 2 nests contained 3. Average number of 

 fledglings/nest was probably less. Becker (1978) reported 1.25 fledglings/nest in 1977 (4 

 nests ) and 1.33young/nest (21 nests) in 1978 in Carter County, Montana. McGahan (1968) 

 ■ reported 1.37-1 .38 young/nest in Park County, Montana in 1963-64. In northeastern 

 Wyoming the number of young/successfiil nest was 1.33-1.65 for 331 nests in 1981-85 

 (Phillips and Beske 1990). 



Breeding Phenology: In Carter County, laying begins in mid-March, with hatching from late 

 April to early May, and fledging in late June through July (Becker 1978). In northeastern 

 Wyoming, the mean egg-laying date is mid-March, with mean hatching in late April, and 

 mean fledging early July (Phillips and Beske 1990). 



Status: A common, widespread breeding species in the area (Becker 1978, Phillips and Beske 

 1990, Phillips et al. 1990). Slightly declining in Montana, but steady in North Dakota 

 (Dobkin 1994); apparently stable throughout the west (White 1994). 



Natural Heritage Program rank: G4; S4 in Montana; S4B,S3N in South Dakota. 



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