FAMILY PARULIDAE 



253 



Migrant and winter visitor from the north. Winters from southern 

 Mexico to Colombia and Venezuela. Very common in the Tropical and 

 Subtropical Zones on both Atlantic and Pacific slopes of Panama east 

 through Chiriqui (especially in the mountains), Veraguas, and Bocas 

 del Toro; fairly common farther east. The species has been recorded 

 on Isla Coiba, Taboga and Taboguilla islands, and San Jose, Saboga, 

 and El Rey (San Miguel) islands in the Perlas Archipelago. Aldrich 

 and Bole (Scient. Publ. Cleveland Mus. Nat. Hist., vol. 7, 1937, p. 

 123) found the Tennessee Warbler to be the most abundant of all the 

 North American migrants on the western slope of the Azuero Penin- 

 sula. This species is more tolerant of conspecifics than are most winter- 

 ing warblers. Early on the morning of March 19, 1957, on the Rio Oria, 

 in southern Los Santos, I flushed a migrant flock of more than 100 

 from the edge of a stream where they had come down to drink. They 

 flew in a fairly close formation, like goldfinches, and swarmed through 

 the trees. 



In addition to insects, nectar is an important food of Tennessee War- 

 blers in winter. Tramer and Kemp (Auk, 1979, pp. 186-187) describe 

 how in Costa Rica individual birds defend from conspecifics as large a 

 section as they can of a flowering Erythrina tree. Morton (pers. 

 comm.) has observed similar behavior in Panama. Skutch (pers. 

 comm. to Ridgely) has found the Tennessee Warbler the only parulid 

 to come to his bird feeder. When foraging for insects, the birds are 

 found from open lawns to forest canopy, usually in groups. 



Tennessee Warblers are present in Panama from mid-September 

 until late April. Ridgely and J. Pujals saw 1 at Ft. Sherman, Canal 

 Zone, on May 1, 1976. Six were banded at the Gorgas Memorial Lab- 

 oratory Station at Almirante, Bocas del Toro, between April 18-24, 

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

 Recaptures of birds at Almirante show that some spend several weeks 

 or possibly the entire winter there; an individual banded on October 21, 



1963, was recaptured there on February 25, 1964 (Loftin et al., Bird- 

 Banding, 1966, p. 41). Another banded at Almirante on October 21, 



1964, was recaptured there the following year on October 20, 1965 

 (Loftin et al., Bird-Banding, 1967, p. 151). One collected by Burton 

 (Bull. Brit. Orn. Club, 1975, p. 85) at Jaque, Darien, weighed 7.5 g. 



The record by Murphy (Fish and Wildlife Service Spec. Sci. Rep 

 Fisheries, no. 279 [mimeo], 1958, p. 110) of the Nashville Warbler, 

 Vermivora ruficapilla, near Coiba and off the Gulf of Panama in No- 

 vember 1956 refers to the Tennessee Warbler, the notes having been 

 placed inadvertantly under the wrong heading. 



