THE DIET OF AN INTRODUCED LIZARD SPECIES, THE BROWN ANOLE (Anolis sagrei), IN CHIAYI COUNTY, TAIWAN

Five hundred-and-two brown anoles ( Anolis sagrei ) were collected for stomach content analysis from an area surrounding a plant nursery in Santzepu, Sheishan District, Chiayi County, as part of an ongoing study on this invasive trunk-ground lizard species. Prey items belonged to the classes Arachnida, Insecta, Chilopoda, Crustacea, Gastropoda and Reptilia. Among them, Hymenopterans were the most common prey items, followed by Aranea, Diptera, Coleoptera, Lepidoptera, and Hemiptera, in that order, and all of these prey types were present in stomach contents every month. Of the Hymenopterans, by far the greatest numbers of prey items were ants. Only five A. sagrei males had vertebrate prey in their stomachs, which made up about 0.2% of all the prey items. This study indicated that although A. sagrei prey on a wide variety of prey types, the food resource diversity is limited to large numbers of only a few prey types, and that the dietary niche of A. sagrei in Taiwan is quite narrow.