French: Buse rouilleuse German: Königsbussard Spanish: Busardo herrumbroso
G. R. Gray
Real del Monte, Hidalgo, Mexico
S Canada from S Alberta to SW Manitoba, S through WC USA to Arizona, New Mexico and NW Texas; winters S to N Mexico (Baja California, Sonora, Durango, Coahuila) and irregularly to C Mexico.
50–66 cm; 980–2030 g, male averages 1050 g, female 1230 g; wingspan 134–152 cm. Largest Buteo, with pale head, broad wings and robust legs and feet... read more
Rather silent. Main call a loud raspy scream, “kraaaah”, c. 1·5 seconds long and... read more
Arid and semi-arid grasslands, sagebrush (Artemisia) and saltbush (Atriplex)... read more
Food and feeding
Relatively narrow diet consisting mainly of mammals (95% by biomass, 83% by frequency), particularly rabbits (Sylvilagus), hares... read more
Nests initiated from Mar–May depending on latitude; in Canada, laying c. 2 weeks later than in centre of range. Large, bulky stick... read more
N populations (Alberta and Saskatchewan in S Canada, Washington east to North Dakota in N USA)... read more
Status and conservation
Not globally threatened (Least Concern). CITES II. Local losses and perceived reduction of entire population have led to calls for listing as threatened species in USA; not... read more
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