FAMILY PARULIDAE 



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low 1800 m. This species is also found in the mountains of Costa Rica. 

 Four specimens from January and February 1902 labeled by Batty, 

 Brava Island, Chiriqui, and Cebaco Island, Veraguas, are certainly er- 

 roneously marked (Eisenmann, Auk, 1950, p. 364). 



The Flame-throated Warbler feeds in typical warbler fashion, mov- 

 ing quickly through the branches of shrubs and trees in search of in- 

 sects; it ranges from treetops to lower levels at woodland edges and 

 shrubby clearings. It often hangs down from pendant leaves that it 

 examines carefully. Buskirk et al. (Auk, 1972, p. 619), studying inter- 

 specific foraging flocks at Cerro Punta, considered this species a long- 

 term follower in such flocks, although rarely were more than 2 indi- 

 viduals part of any flock. Ridgely (1976, p. 292) describes the song as 

 "a weak dry buzz, zeeeeoo." Mr. and Mrs. Rodman Ward (in litt. to 

 Eisenmann) reported seeing this species on April 3, 1959, at 2300 m 

 on Cerro Punta and watched 1 as it uttered a buzz zeeeeee-u (slightly 

 inflected at the end) , and heard (without seeing the singer) a very high- 

 pitched buzzy tsip-i-tsip-i-tsip-i-tee. Eisenmann has heard only call 

 notes such as tsip; tick, tick; or diick duck. 



Nothing is recorded about the nesting habits of this bird in Panama, 

 but Skutch (Nutt. Orn. Club, no. 7, 1967, pp. 137-143) has studied it 

 in detail in Costa Rica, where he found them nesting from mid-March 

 through June. Half the nests Skutch found were well up in trees, be- 

 tween 6 and 25 m from the ground, and half were in niches on grassy 

 banks. All the nests, whether terrestrial or arboreal, though not roofed, 

 were well covered by growing vegetation, either by dense grass or moss 

 or by epiphytes or broad-leafed bromeliads on trees. The nest, built 

 entirely by the female, is made primarily of green moss and liverworts; 

 some fine plant fibers and horsehair may be used in the lining, but even 

 here green moss predominates. One nest measured by Skutch was 8 

 cm in height by 10 or 12 cm in diameter; the cavity was 5 cm in diameter 

 by 3 cm deep. In every case that Skutch could determine, the clutch 

 was 2 eggs, these vary in pattern from unspotted white to faintly and 

 finely sprinkled with brown over the entire surface. Measurements of 

 4 eggs were from 16.2 X 12.9 to 19.0 X 13.1 mm. 



Incubation is done exclusively by the female and takes approximately 

 16 days. The young hatch with orange-pink skin and long but sparse 

 gray down. Their mouth lining is yellow on the marginal regions and 

 pink or pale red in the more central and deeper regions, unlike the 

 mouth linings of most passerine nestlings, which are uniform yellow or 

 yellow-orange. The young are fed small green caterpillars by both 

 parents and leave the nest at approximately 13 days. 



