FAMILY PARULIDAE 



30I 



edges, which have more soft-bodied larval forms available. The re- 

 duction of the black mask also seems correlated with a drier environ- 

 ment." 



ICTERIA VIRENS VIRENS (Linnaeus): Yellow-breasted Chat, 

 Reinita Arriera 



Turdus virens Linnaeus, 1758, Syst. Nat., ed. 10, 1, p. 171. (South Carolina.) 



Medium size; upper surface yellowish olive; abdomen and undertail 

 coverts white; rest of undersurface yellow. 



Description. — Length 151-174 mm. Adult (sexes alike), forehead 

 gray; superciliary and lower rim of eye white; lores black; upper sur- 

 face and wing coverts yellowish olive; remiges and rectrices dusky with 

 outer webs edged light yellowish olive; auricular region gray; thin 

 white stripe on side of throat; throat to belly bright yellow; flanks gray; 

 rest of undersurface white; bend of wing and underwing coverts yellow. 



Measurements. — Males ( 10 from the breeding range, taken in May) , 

 wing 71.0-78.0 (75.5), tail 69.6-77.5 (74.4), oilmen from base 14.2- 

 17.0 (15.3), tarsus 24.3-27.0 (25.7) mm. 



Females (10 from the breeding range, taken in June), wing 71.8- 

 80.0 (76.5), tail 66.5-83.4 (76.2), culmen from base 14.9-16.1 (15.4), 

 tarsus 24.7-27.8 (26.0) mm. 



Winter visitor from the north. Uncommon in the lowlands of west- 

 ern Bocas del Toro, where it has been recorded at Almirante and at the 

 mouth of the Rio Teribe on the Rio Changuinola. The first specimen 

 known from Panama was collected at Almirante by H. von Wedel on 

 January 16, 1929, but banding results suggest that it is not rare there: 

 in 1963, 16 were netted October 1-31 and 3 were netted April 17-21 

 (Loftin and Olson, Carib. Journ. Sci., vol. 3, no. 4, 1963, p. 195). 

 Banding also indicates that Yellow-breasted Chats return to the same 

 site in succeeding years. One banded at Almirante April 17, 1963, was 

 recaptured there October 17 and 18, 1963, and again October 22 and 

 November 1, 1965, (Loftin et al, Bird-Banding, 1967, p. 152). The 

 only report of this species elsewhere in Panama, and the most southern, 

 is a sighting of 1 on Cerro Campana ( far to the east of any other record 

 and the only one from the Pacific slope) on September 14, 1961, by 

 Richard Ryan and Ned Boyajian (Ridgely, 1976, p. 301). In Panama, 

 as in its breeding range, the chat usually stays well hidden in dense 

 undergrowth of brushy areas and woodland borders. 



