Autumn stopover ecology of the BlackpollWarbler (Dendroica striata) in thorn scrub forestof the Dominican Republic

We used mist-netting, color-banding, resighting, and behavioral observations to study the autumn stopoverecology of migrating Blackpoll Warblers (Dendroica striata) in coastal thorn scrub forest in the area of Cabo Rojo,Pedernales Province, Dominican Republic. Blackpoll Warblers were the most abundant migrant present in this habitatthroughout most of October 1997. Warblers stopping over in this habitat were generally young with moderate to largefat stores. No lean birds (fat score = 0) were captured. Our behavioral observations suggest that Blackpoll Warblers areflexible in terms of social organization, with birds associating in single-species flocks and in mixed-speciesaggregations, but single birds were also recorded. Foraging activity consisted primarily of gleaning from leaves andwas focused on lepidopteran larvae, whose high abundance coincided with Blackpoll Warbler arrival. We suggest thatmost stopover Blackpoll Warblers were not weakened individuals searching for emergency energy stores but wereforced down owing to unfavorable weather conditions for migration; others may have been taking advantage of landfallon the south coast of Hispaniola for daytime rest before continuing across the Caribbean Sea to South America.Coastal thorn scrub forest of Hispaniola appears to be a preferred stopover habitat for a variety of migrants, providinga place to rest and replenish energy reserves following transoceanic flight.

Steven C. Latta and Christopher Brown, Can. J. Zool. 77: 1147-1156 (1999)