RED-EYED BRONZED COWBIRD 459 



altitudinal, even in the tropical portions of their range. In the 

 mountains above Tecpan, Guatemala, I found them at between 

 8,000 and 9,000 feet only during the nesting season, from March 

 until July. During this period they were a familiar sight in the 

 pastures about the house which I occupied from early February 

 until the end of the year. But in August they vanished, apparently 

 having descended to lower and warmer regions, and were not seen 

 again in this locality during the remainder of the year, although 

 a few were found on the plateau a thousand feet lower. During the 

 year I spent near Vara Blanca, living in a narrow clearing in the 

 midst of the rain forest of this excessively wet region on the northern 

 slope of the Cordillera Central of Costa Rica, at 5,500 feet above 

 sea-level, the first red-eyed cowbird was seen on March 28, just as 

 the nesting season was beginning for the majority of the local birds. 

 I had been present in the same spot since the preceding July, without 

 having seen a single individual. In this instance, I think it probable 

 that the cowbirds had arrived from the cultivated lands of the central 

 plateau to the south, passing over the continental divide, which here 

 was about 6,800 feet high. To the north were scarcely broken forests 

 leading down to the Caribbean lowlands, where the species is not 

 known to occur." 



Courtship. — A. F. Skutch (MS.) gives the following account of 

 the courtship: "In the middle of March, I watched a flock of about 50 

 red-eyed cowbirds foraging in a compact group around a straw-pile 

 beside a granary in the Guatemalan highlands, at an altitude of 7,300 

 feet. Apparently the birds were picking up waste grain. From time 

 to time, from no apparent cause, they would all take wing in a body, 

 wheel around in a close flock, then drop down again to continue their 

 gleaning. The breeding season was approaching, and the male cow- 

 birds were already in an amorous mood. Now and again one would 

 rise a few feet into the air and hover prettily on beating wings above 

 one of the females. Other males perched in the pine trees scattered 

 about the field, where each spread and raised his cape until it sur- 

 rounded his head like a black halo, and sang with low, squeaky 

 whistles. 



"One evening in July, at about sunset, I witnessed the courtship of 

 a pair of red-eyed cowbirds beside the Ulna River in Honduras. The 

 female was walking over a lawn, feeding, and the male followed her 

 with his head thrown back, chest puffed out in front, and wings 

 quivering, walking with a stiff, seemingly unnatural gait. Of a 

 sudden he jumped into the air and remained for about a minute poised 

 on vibrating wings, about a yard above the female. Then he dropped 

 to the ground in front of her, and with out-fluffed plumage bobbed 

 up and down by flexing his legs. She considered him for a moment, 



