FAMILY FRINGILLIDAE 



565 



Females (10 from Bocas del Toro, Costa Rica, and Honduras), 

 wing 48.0-52.4 (50.0), tail 39.6-46.0 (42.4), culmen from base 9.0-10.2 

 (9.6), tarsus 13.3-15.3 (14.7) mm. 



Resident. Known in Panama only from the lowlands of western 

 Bocas del Toro and western Chiriqui. It was first discovered in Pan- 

 ama at Changuinola, Bocas del Toro, in 1956 by Eisenmann (Condor, 

 1957, p. 259) , who saw at least 30 there during June and July. In April 

 and May, 1980, Ridgely (in litt.) found it fairly common in Changui- 

 nola. During October and November 1962, the Gorgas Memorial 

 Laboratory collected 2 at Almirante, Bocas del Toro. On December 

 16, 1962, Eisenmann found a singing male and several females at Fron- 

 tera, Chiriqui, along the road skirting the west bank of Rio Chiriqui 

 Viejo, about a quarter mile from the Costa Rica border. Elsewhere in 

 Chiriqui, I saw at least 3 at Puerto Armuelles on March 6, 1966, and 

 Ridgley (1976, p. 333) found 4 at the David Airport on January 18, 

 1974, where as of 1981 it was being seen regularly. In March 1976, 

 Ridgely (in litt.) saw about 25 near Estero Rico. North of Panama, 

 this race ranges to northern Veracruz, Mexico; other races are found 

 north to southern Texas. 



This seedeater inhabits open, grassy country. When I saw them at 

 Changuinola in 1958 they seemed to be grouped in little colonies where 

 15 to 30 or more would occupy an area of a few acres, whereas they 

 would be absent over wide stretches of field between. Their preference 

 is for sections along dikes and old lagoons, where the ground is some- 

 what broken and is grown with bunch grass and weeds. It must have 

 been in such areas along the open banks of the Changuinola and other 

 rivers that they found their original habitat. The song, as described by 

 Eisenmann (op. cit.), is a series of sweet, rich notes, swee-swee-swee- 

 swee-swee, teeoo-teeoo-teeoo, tew tew tew tew, the last notes very 

 canary-like. 



Of the 4 males I collected at Changuinola on February 13, 1958, the 

 2 "immatures" with brown backs had testes fully developed while those 

 that were fully black had the sexual organs smaller. The females were 

 very shy. Whenever one appeared on an open perch, one or two males 

 would make a pass at her and she would fly down into the cover of the 

 grass. Skutch (Pac. Coast Avif. no. 31, 1954, pp. 33-37) has found 

 nests of this species in Costa Rica between May and December. The 

 nest is placed in a clump of grass, bush, or low tree, usually from 1 to 

 1.6 m from the ground. It is built entirely by the female and is a cup 

 with an outer layer of cobwebs, filled in with rootlets, fibers, and 

 grasses, and lined with horse hairs, when available. Two, or more 



