FAMILY PARULIDAE 



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Fairly common, arrives in Panama as early as August 24 (Arbib and 

 Loetscher, Auk, 1935, p. 327), with some remaining until early April 

 (April 4, 1911, Lion Hill, Canal Zone, specimen; April 5, 1976, Pipe- 

 line Road, Canal Zone, Ridgely) ; commonest as a migrant in September 

 through mid-October and March. The Black-and-white Warbler is 

 found throughout the Republic in winter, although less numerous east 

 of the Canal Zone; it is commonest in the lowlands, but I have seen it 

 as high as 1560 m at Cerro Punta, Chiriqui. It has also been found on 

 Taboga and Urava Islands and on San Jose on the Pearl Islands; the 

 British Museum of Natural History has a specimen collected October 

 25, 1924, at sea in the Gulf of Panama. 



Figure 22. — Black-and-white Warbler, Reinita Trepedora, Mniotilta varia, male. 



As a migrant and winter visitor the Black-and-white Warbler be- 

 haves just as it does in the north, climbing the trunks and main branches 

 of trees in search of insects. Buskirk et al. (Auk, 1972, p. 619) found 

 that at Cerro Punta Black-and-white Warblers will join the local inter- 

 specific flocks of insectivorous birds, but will not travel with them 

 for any distance. I have also seen them with other migrant warblers. 

 Skutch (A Naturalist in Costa Rica, 1971, p. 104) found that in Costa 



