Food of the Marine Toad, Bufo Marinus, and Six Species of Skink in a Cacao Plantation in New Britain, Papua New Guinea.

Abstract

Toads and skinks were caught in cocoa plantations on 1 day each month of 1972 between 0800 and 1500 h for examination of stomach contents. They were marine toads (Bufo marinus), introduced in 1939 to control sweet potato hawkmoth (Hippotion caleria) and known to eat pests of cocoa and sugar cane and beneficial insects including introduced predators. Ants were 46% of dietary items of toads, snails were 42%. The other 12% were 4 orders of insect. They included 2 beetles of economic importance, adult cacao weevil borer (Pantorhytes plutus) and adult dung beetle, an unidentified species of Scarabaeinae. Presence of toads should be considered before exotic dung beetles are introduced. The ant Oecophylla smaragdina was 15% of food items; it is thought to control some insect pests of cocoa and toads may check its spread.The skinks ate mostly lepidopteran larvae from the trees, though Lamprolepis smaragdinum and Sphenomorphus jobiensis were found mainly on the ground. Cacao webworm larvae (Pansepta teleturga) were 6% of food items in Emoia baudinii and 1% in E. callisticta and E. mivart; those larvae channel into cocoa branches and would have to be sought actively. The other skink studied was Carlia fusca. All were general predators but with some selection. They may be the natural controls of defoliating caterpillars.