Monday, December 31, 2012

Treeboa Diets

 Ruschenberg's treeboa from the Frenchman's River, Tobago. JCM
Nine species of  Neotropical treeboas in the genus Corallus range from southeastern Guatemala to southeastern Brazil. Based largely on previously published papers, Henderson and Pauers (2012) accumulated records for 271 prey items for all species combined. Prey reported were: 2 frogs, 69 lizards (mostly Anolis), 1 snake, 65 birds, and 134 mammals (mostly marsupials, rodents, and  bats). The authors found a conspicuous difference in diet between the two West Indian species (C. cookii and C. grenadensis) and species occurring on the mainland. Juvenile and subadult boas from the West Indies prey almost entirely on anoles, whereas on the mainland (with the notable exceptions of C. batesii and C. caninus), preyed mostly on birds and bats. Four species (C. cookii, C. grenadensis, C. hortulanus, and C. ruschenbergerii) are vertebrate generalists and exhibit both active foraging and ambush hunting modes. Adult C. batesii and C. caninus (and, perhaps, C. cropanii) are specialists on mammals, and may only use an ambush hunting techniques, and these were the only species that did not have at least three records of birds in their diet. Although more common than the critically endangered C. cropanii, both C. annulatus and C. blombergii seem genuinely rare and it is premature to make any generalizations regarding their trophic biology.

 The longest of the nine treeboa species is Ruschenberg's treeboa, but it has less bulk than three of the other species (batesii, canius, cropanii) based on body girths. Ruschenberg's treeboa has a large distribution, ranging from Costa Rica to Venezuela, and it occurs on Trinidad, Tobago, and the Isla de Margarita. The authors found it feeds on lizards, birds, marsupials, rodents and carnivores (mongoose).

Henderson, R. W. and Pauers, M. J. 2012. On the Diets of Neotropical Treeboas (Squamata: Boidae: Corallus). South American Journal of Herpetology 7:172-180.