62 FALCONID^E. 



297. BUTEO ERYTHRONOTUS (King). 

 (RED-BACKED BUZZARD.) 



Buteo erythronotus, Sharpe, Cat. B. i. p. 172 ; Scl. et Salv. Nomencl. p. 119; 

 Scl P. Z. S. 1872, p. 536 (Rio Negro) ; Dumford, Ibis, 1877, p. 38, et 

 1878, p. 397 (Patagonia) ; Salt-in, Ibis, 1880, p. 362 (Salta) ; Barrows, Auk, 

 1884, p. 109 (Azul); Withington, Ibis, 1888, p. 469 (Lomas de Zamora). 

 Buteo tricolor, Burm. La-Plata Reise, ii. p. 436 (Mendoza and Tucuman). 



Description. Above slaty blue ; wing-feathers slaty, with narrow transverse 

 bars of black ; upper tail-coverts and tail white, the latter with a broad black 

 subapical band and numerous narrow grey cross bars : beneath white, with 

 slight grey cross bars on the belly ; bill black ; feet dirty yellow : whole length 

 25 inches, wing 18-5, tail 10-0. Female similar, but back deep chestnut. 



Hab. Southern portion of South America. 



This is a fine bird the king of South- American Buzzards. In the 

 adult female the three colours of the plumage are strongly contrasted ; 

 the back being rusty rufous, the rest of the upper parts grey, the whole 

 under surface pure white. It is occasionally met with in the northern 

 provinces of the Argentine Republic, but is most common in Patagonia ; 

 and it has been said that in that region it takes the place of the nearly 

 allied Buteo albicaudatus of Brazil. In habits, however, the two species 

 are as different as it is possible for two raptores to be; for while 

 the northern bird has a cowardly spirit, is, to some extent, gregarious, 

 and feeds largely on insects, the Patagonian species has the preying habits 

 of the Eagle, and lives exclusively, I believe, or nearly so, on cavies and 

 other small mammals. When Captain King first discovered it in 1827, 

 he described it as " a small beautiful Eagle." In Patagonia it is very 

 abundant, and usually seen perched on the summit of a bush, its broad 

 snowy- white bosom conspicuous to the eye at a great distance one of the 

 most familiar features in the monotonous landscape of that grey country. 

 The English colonists on the Chupat, Durnford says, call it the "white 

 horse/' owing to its conspicuous white colour often deceiving them 

 when they are out searching for strayed horses in the hills. It is a 

 wary bird, and when approached has the habit of rising up in widening 

 circles to a vast height in the air. When sailing about in quest of prey 

 it usually maintains a height of fifty or sixty yards above the surface. 

 The stomachs of all the individuals I have examined contained nothing 

 but the remains of cavies (Cavia australis}. 



The nest is built on the top of a thorn bush, and is a large structure 

 of sticks, lined with grass, fur, dry dung, and other materials. " The 

 eggs are greyish white in colour, blotched and marked, principally to- 

 wards the large end, with two shades of umber-brown " (Gould). 



