Abstract
The Sickle-billed Vanga Falculea palliata forages by probing its long and slender bill into cracks on the trunks and branches of trees. To determine the diet of adult and nestling Sickle-billed Vangas and the kinds of prey obtained with this foraging technique, six nests in the Ankarafantsika Strict Nature Reserve, western Madagascar, were observed during the November to December nestling periods in 1999 and 2000. Diet was investigated by direct observation. Of the 41 items of prey identified (out of 68 total prey items) in adult Sickle-billed Vangas, crickets, cockroaches, spiders, and grasshoppers constituted 29.3%, 19.5%, 17.1%, and 12.2%, respectively, of the prey items. These four groups together accounted for 78.0% of the identified prey. Parents delivered 1, 180 prey items to the nestlings. The most numerous food items were crickets, accounting for 41.6% of 262 identified prey, followed by cockroaches (21.4%) and grasshoppers (15.6%). These three groups together accounted for 78.6% of the identified prey. Sickle-billed Vangas never foraged on the ground but preferred dead trees of five metres or higher for foraging, and it is thus highly probable that all prey items were of arboreal origin. Arboreal cockroaches inhabit holes and cracks on dead trees and branches, and it is likely that Sickle-billed Vangas capture them primarily using the probing technique.
