Larval salamanders are as effective at short-term mosquito predation as mosquitofish

Abstract

Biological control of mosquitoes can have unintended ecological consequences. One example is the introduction of the genus Gambusia Poey, 1854 into ponds and wetlands. Gambusia spp. are invasive in many parts of the world and have the potential to alter ecosystems by changing trophic interactions and extirpating amphibians. We sought to determine whether larval amphibians are capable of consuming larval mosquitoes as effectively as Gambusia spp. We tested the predation ability of larval Spotted Salamanders (Ambystoma maculatum (Shaw, 1802); n = 13), Southern Leopard Frog (Rana sphenocephala Cope, 1886; n = 12) tadpoles, and western mosquitofish (Gambusia affinis (Baird and Girard, 1853); n = 13) across a range of body sizes in laboratory experiments. Our results showed that over a 24 h period, salamander larvae (mean ± SE; 238 ± 14) and mosquitofish (195 ± 17) consumed a statistically equivalent number of mosquito larvae, whereas tadpoles consumed a large number (113 ± 14) but significantly less. All species had significant (or marginally significant) positive relationships between body size and rate of mosquito consumption. Further studies into the ability of native larval amphibians to consume mosquito larvae are needed to assess whether amphibians can be successful at mosquito control instead of introducing nonnative species to new areas.