Three Anuran Tadpoles from Odisha do not help in mosquito biocontrol

Abstract

All the mosquitoes and amphibian species share the aquatic habitat for reproduction, growth and survival of respective larvae. The amphibian tadpoles and different instars of mosquito larvae interact with each other in several ways: both negative and positive. The trophic relationship between the tadpoles of three common anuran species of Odisha, India (Duttaphrynus melanostictus, Polypedates maculatus and Microhyla ornata) and various instars of Anopheles vagus larvae was examined. Initial and late feeding stages (varying sizes and feeding abilities) of tadpoles in starved/well-fed conditions were kept for up to 48 hours in different bowls containing Anopheles vagus larvae (both tadpoles and mosquito larvae in differential densities). There was no evidence of active predation of all three species on larvae of Anopheles vagus. Size, feeding state and density did not evoke any feeding relationship among the larvae. However, conspecific cannibalism was observed among the tadpoles but not among the mosquito larvae. The study concludes that these tadpoles cannot function as suitable mosquito biocontrol agents. Larvae of both the groups might be involved in other types of interactions which needs further investigation.