400 BIRDS OF THE REPUBLIC OF PANAMA PART 4 



Measurements. — Males (10 from Panama, Colombia, and Costa 

 Rica), wing 50.0-54.2 (51.8), tail 22.3-32.1 (27.5), oilmen from base 

 7.7-9.3 (8.2), tarsus 10.8-13.5 (12.4) mm. 



Females (10 from Panama, Colombia, and Costa Rica), wing- 48.8- 

 54.5 (51.9), tail 22.7-28.1 (26.4), oilmen from base 7.9-8.7 (8.4), tar- 

 sus 12.2-13.4 (12.6) mm. 



Resident. Uncommon to fairly common locally in lowlands and 

 foothills on the Caribbean slope; more scattered on the Pacific slope. 

 It has not been found in Chiriqui since Arce took 2 males at Bugaba in 

 the 1860's (Salvin, Proc. Zool. Soc. London, 1870, p. 1). Due to al- 

 most complete deforestation, it may no longer occur here. Ridgely and 

 F. G. Stiles saw 3 above Santa Fe, Veraguas, in January 1974 (in lift. ) 

 and it is also recorded in eastern Province of Panama in the Cerro 

 Azul/Jefe area and various localities in Darien ( Ridgely, 1976, p. 315) . 

 Beyond Panama, this race ranges to southern Mexico and western 

 Ecuador; the nominate form is found east of the Andes to central 

 Bolivia. 



This smallest of the euphonias inhabits humid forest and forest bor- 

 ders and almost always forages high in trees. On the Pipeline Road in 

 the Canal Zone, where James Karr found it regularly during 1969, he 

 never saw one below heights of 8 to 12 m; they continue to be found in 

 this locality, in small numbers (Ridgely, in litt. ) . Like other euphonias, 

 this species feeds extensively on mistletoe berries, but Skutch (Publ. 

 Nutt. Orn. Club., no. 10, 1972, p. 182) believes they also take more in- 

 sects and spiders than do their congeners. They are often part of mixed 

 species flocks. Five collected by Strauch (Bull. Brit. Orn. Club, 1977, 

 p. 64) weighed from 9.4 to 11.5 g. When feeding, males frequently 

 utter little calls; both sexes also have a thin, sharp note. 



Skutch (op. cit., pp. 183-187) found three nests of this species in 

 Costa Rica; the nest was in use between late March and August. The 

 nests were 5 to 7 m from the ground surrounded by mosses or epiphytes 

 and were globular with an entrance on the side. One nest was made of 

 moss with orchid roots and living ferns, with a lining of grass blades 

 and very fine plant fibers. Both sexes worked at nest construction. The 

 usual clutch seems to be three eggs; they are white, heavily blotched and 

 spotted with brown. The growth rate of these euphonias is notably 

 slower than that of most tanagers, especially considering their small 

 size; incubation requires at least 17 days, and the young, which hatch 

 with very sparse down, are not feathered until about 15 days old. They 

 are fed regurgitated food that Skutch could not identify, and leave the 

 nest at 20 days, when they can fly well. 



