522 BIRDS OF THE REPUBLIC OF PANAMA — PART 2 



upper throat to light green ; tarsus and toes blue ; claws black ; under- 

 side of toe pads, except for distal segment, dull honey yellow. 



Measurements.— Males (12 from Panama) wing 190-205 (197.1), 

 tail 149-168 (156.4), culmen from base 125.3-155.7 (137.3), tarsus 

 47.4-52.5 (49.3) mm. 



Females (10 from Panama and northwestern Colombia) wing 184- 

 191 (189.4), tail 143.5-155.0 (148.6), culmen from base 113.7-144.8 

 (119.9), tarsus 45.3-50.0 (48.0) mm. 



Resident. Distributed throughout forested areas in the lowlands ; 

 less common on the Pacific slope west of the Canal Zone ; to 900 meters 

 elevation in mountain areas. 



The species, now uncommon in the lowlands of the Azuero Penin- 

 sula, Pacific Veraguas, and Chiriqui, undoubtedly has decreased as 

 forests have been cleared. Through the savannas a few may be found 

 in stands of trees along streams, or in the wet forests bordering the 

 mangrove swamps, but there they are not common. On the eastern 

 side of the Azuero Peninsula in Herrera I found a few in 1948 in 

 the hills known as Los Voladores, and others in 1957 in Los Santos 

 along the Rio Oria, and in 1962 on the Rio Guanico. From Cerro Azul 

 through Darien, and along the entire Caribbean slope they are com- 

 mon, and on the whole are the most prominent among the larger 

 forest birds. It is usual to find them in small groups of 6 or 8 that 

 move about through the tops of the trees, often in early morning 

 resting on open perches in the sun. In flight the rounded wings beat 

 rapidly for half a dozen strokes or more, and then are held wide open 

 for a short sail during which the bird dips suddenly downward almost 

 as if pulled by the long bill. Their movement forward thus is strongly 

 undulating and rather slow. Usually they move in the open for short 

 distances only across openings over streams or small clearings. But, 

 though the flight seems weak, it can be long sustained without diffi- 

 culty, as they cross easily between distant forested ridges, or less often 

 over extensive open lands. It is their notes that indicate their abun- 

 dance, the ordinary call being a sharp ka-trik ka-trik ka-trik, that may 

 be repeated steadily for periods of several minutes. At a distance this 

 is not unpleasing, but near at hand it may become annoying through 

 its unvarying, monotonous repetition. Other lower, rattling calls are 

 heard when birds are near at hand. 



The food is mainly fruits of forest trees, varied by cicadas and other 

 large insects. Where some group of trees is bearing in abundance 

 15 or 20 of the great birds may gather to feed quietly in company 

 with parrots, trogons, and large flycatchers. 



