FAMILY THRAUPIDAE 



453 



Immature male, like female, but with irregular red splotches. 



Measurements. — Males (10 from Panama), wing 91.0-96.0 (94.6), 

 tail 65.2-70.7 (68.8), culmen from base 18.7-19.6 (19.2), tarsus 15.8- 

 19.1 (16.9) mm. 



Females (10 from Panama), wing 87.1-94.0 (89.9), tail 59.3-69.5 

 (66.1), culmen from base 17.5-19.3 (18.7), tarsus 16.0-18.3 (16.9) 

 mm. 



Migrant and winter visitor from the north. Very common through- 

 out the lowlands and foothills; in the Chiriqui highlands it has been 

 collected as high as 2250 m (though more numerous below 1800 m) 

 on Volcan de Chiriqui (Blake, Fieldiana: Zool., vol. 36, no. 5, 1958, p. 

 567). It has also been taken at many of the islands off the Pacific 

 Coast and at Isla Escudo de Veraguas and Isla Bastimentos, Bocas del 

 Toro, off the Caribbean Coast. The Summer Tanager has been re- 

 corded in Panama from September 3 (Eisenmann, Smiths. Misc. Coll., 

 vol. 117, no. 5, 1952, p. 55) until April 22 (Loftin and Olson, Carib. 

 Journ. Sci., vol. 3, no. 4, 1963, p. 195). Most individuals depart in 

 March. I have seen a flock of 30 in a single tree in December. Summer 

 Tanagers winter from Mexico to northern Bolivia and Amazonian 

 Brazil. 



The Summer Tanager frequents second-growth woodlands, gardens, 

 and shrubby areas when in Panama. Many that I have collected here 

 had the stomach filled with small, stingless, black bees, and once I 

 watched one prying into a bees' nest. Buskirk et al. (Auk, 1972, p. 

 620) observed that Summer Tanagers at Cerro Punta, would join but 

 not follow the local interspecific flocks of insectivores. Seven Summer 

 Tanagers captured at Cerro Punta during April 1968 had an average 

 weight of 30.3 g; this is 3.3 g more than 3 taken there a month earlier 

 (Leek, Bird-Banding, 1975, p. 202). One killed at Almirante, Bocas 

 del Toro, while migrating south on October 13, 1963, weighed 31.8 g 

 (Rogers, Bird-Banding, 1965, p. 116). A male collected by Strauch 

 (Bull. Brit. Orn. Club, 1977, p. 65) in January weighed 28.9 g. 



The Summer Tanager is not known to sing while in Panama, but 

 does frequently give its distinctive call, pitichuck or pi-tuck. 



PIRANGA OLIVACEA (Gmelin): Scarlet Tanager, Frutero Escarlata 



Tangara olivacea Gmelin, 1789, Syst. Nat., 1(2), p. 889. (New York.) 



Medium size; male in alternate plumage, entire body scarlet, with 

 wings and tail black; male in basic plumage, mostly olive-yellow with 

 black wings and tail; female mostly olive-yellow. 



Description. — Length 155-171 mm. Adult male in basic plumage, 



