8 



BIRDS OF THE REPUBLIC OF PANAMA PART 4 



from several flying with Barn and Rough-winged Swallows. In the 

 Canal Zone, Eisenmann on February 1, 1973, found a small flock near 

 Gamboa, and on February 4, a larger group of 200-300 at the Gatun 

 Dam spillway. On February 16, 1969, Ridgely (1976, p. 259) photo- 

 graphed Tree Swallows that were part of a flock of 225 at the Gatun 

 Dam. In the early months of 1975 and of 1976 flocks were seen in vari- 

 ous locations in the Canal Zone; Ridgely (in litt.) found as many as 

 600 at La Jagua on January 27, 1976. The latest date for which the 

 species is recorded in Panama is April 5, when in 1975 Eisenmann (in 

 litt.) and others saw 6 (2 adults) at Gatun Lake. 



Tree Swallows are not found in Panama every year, but the species 

 has recently been seen in northern Colombia (20 at Salamanca Na- 

 tional Park, Magdalena, February 6, 1977, by Ridgely) and in northern 

 Venezuela (at Chichiriviche Lagoon, Falcon, by P. Alden in 1972 and 

 1976), suggesting that they often travel farther south than was pre- 

 viously known. 



TACHYCINETA ALBILINEA (Lawrence): Mangrove Swallow, 

 Golondrina Manglera 



Figure 1 



Petrochelidon albilinea Lawrence, Ann. Lyc. Nat. Hist. New York, vol. 8, May 

 1863, p. 2. (Atlantic slope, near the Panama Railroad, Canal Zone, Panama.) 



Small; undersurface, rump, line above lores, and tips of secondaries 

 white. 



Description. — Length 105-115 mm. Adult (sexes alike), crown, 

 hindneck, back, scapulars, lesser wing coverts, and upper tail coverts 

 steel blue, with a greenish to bluish sheen (greener when in fresh plum- 

 age); a narrow line above lores white; lores and narrow line beneath 

 the eye black; wings and tail dull black; tertials and middle wing coverts 

 edged narrowly with white; lower hindneck with feathers white basally, 

 this reduced in some to an indistinct white line; rump white, with 

 finely marked dusky shaft lines; lower surface, including underwing 

 coverts, white, with the breast and sides faintly washed with pale gray. 



Immature, lores dull black, bordered above by a narrow white line; 

 rump white; rest of upper surface, with the wings, drab gray; under- 

 surface white, with a faint wash of somewhat brownish gray on breast 

 and sides; outer underwing coverts banded indistinctly with dull gray. 



A female collected at Canita, on the Rio Bayano above El Llano, 

 February 6, 1962, had the iris wood brown; tarsus and toes fuscous- 

 black; claws black. In another female, at Puerto Armuelles, Chiriqui, 



