212 BIRDS OF LA PLATA 



At the approach of cold weather the Dominican 

 Gulls leave the sea-shore and wander inland and 

 northward. At this season they are almost exclu- 

 sively flesh-eaters, with a preference for fresh meat ; 

 and when the hide has been stripped from a dead 

 cow or horse they begin to appear, vulture-like, 

 announcing their approach with their usual long, 

 hoarse sea-cries, and occasionally, as they circle about 

 in the air, joining their voices in a laughter-like 

 chorus of rapidly repeated notes. Their winter 

 movements are very irr^;ular; in some seasons 

 they are rare, and in others so abundant that they 

 crowd out the Hooded Gulls and Carrion-Hawks 

 from the carcase ; I have seen as many as five to six 

 hundred Dominicans massed round a dead cow. 



ARGENTINE BLACK-HEADED GULL 



Larm macuHpemis 



Head and nape brownish-black (in breeding dress) ; tail and under- 

 parts white ; mantle pale grey ; primaries black or dark grey, tipped 

 with white, and with large elongated white patches on the outer portions 

 of first to fifth, followed by a subapical black bar (in L. glaucodes the 

 lower portion is white) ; underwing pak grey ; bill, legs, and feet 

 blood-red; length 17, wing 11.5 inches. 



This common Black-headed Gull is found through- 

 out the Argentine country, down to Chupat in Pata- 

 gonia, and is exceedingly abundant on the pampas 

 of Buenos Ayres, where it is simply called Gaviota 

 (Gull). In the month of October they congregate 

 in their breeding-places — extensive inland marshes. 



