FAMILY PARULIDAE 



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out in the lowlands of both slopes, particularly in mangroves and near 

 water, both running and still. I have also seen them among the jumbled 

 rocks along the beach on San Jose in the Pearl Islands, where they are 

 common throughout the group, and on the ocean beach at Isla Goberna- 

 dora, Veraguas. In migration they are encountered away from water 

 as well, on the paths in dry woods, and in the highlands. On Volcan 

 de Chiriqui, Monniche (Blake, Fieldiana: Zool, vol. 36, no. 5, 1958, 

 p. 559) collected Northern Waterthrushes as high as 1590 m during 

 October, and W. W. Brown, Jr. (Bangs, Proc. England Zool., Club, 

 vol. 3, 1902, p. 62) collected a male at Boquete (1200 m) on March 27, 

 1901. Eisenmann saw 1 above Cerro Punta, Chiriqui at approximately 

 2100 m on September 19, 1958. Northern Waterthrushes arrive in 

 Panama in late September and most depart by late April. Extreme 

 dates known to Eisenmann (in litt.) are September 11 to May 13 (both 

 Ft. San Lorenzo, Canal Zone) . In the exceptionally long dry season of 

 1977, however, N. G. Smith saw 2 together at Summit Gardens on May 

 26 and June 2; several other northern migrants also remained late. At 

 Almirante, Bocas del Toro, in the southward migration of 1964, 15 were 

 netted on September 29 and 16 on October 10; the following spring- 

 numbers netted were much fewer, not exceeding 2 or 3 in any one day 

 between March 21 and April 23 (D. L. Hicks in litt. to Eisenmann). 



Banding results suggest that many of the individuals that do not con- 

 tinue on to South America are highly sedentary while in Panama; 

 Loftin et al. (Bird-Banding, 1966, p. 42) banded a Northern Water- 

 thrush in the Canal Zone October 5, 1963, that was recaptured there on 

 February 9, 1964. One banded at Almirante, November 10, 1962 was 

 retaken there January 7, 1963, and again on October 14, 1963, indicat- 

 ing that some individuals return to the same wintering area in subse- 

 quent years, as they have been shown to do in Venezuela ( Schwartz, 

 Living Bird, 1964, pp. 169-184). Of the 65 birds banded by Loftin 

 and his associates in the Canal Zone and the 338 banded at Almirante 

 in 1963 and 1964, there were 5 repeats in the Canal Zone and 15 at 

 Almirante. In another banding study at Almirante, Rogers and Odum 

 (Wils. Bull., 1966, p. 418) weighed 165 Northern Waterthrushes, 

 which ranged between 10.5-19.2 (14.69) g, and found that, unlike sev- 

 eral other migrant species, including the Ovenbird, the waterthrushes 

 had not exhausted their fat reserves. 



Willis (Living Bird, 1966, p. 207) observed individuals picking at 

 insects flushed by swarms of army ants on Barro Colorado Island; 

 however, the birds were never persistent swarm followers. The weights 

 of 7 collected by Burton (Bull. Brit. Orn. Club, 1975, p. 85) ranged 



