Conservation planning relies on accurate estimates of focal species’ population sizes. For amphibians, population size can be estimated from acoustic monitoring, because amphibians call to attract mates and signal occupancy of territory. However, a difficulty with acoustic monitoring is that amphibian activity and call audibility is affected by the structure of the environment, whether it be a natural or human-modified environment. How do habitat structure and urban noise interact to modify amphibian calling activity and the audibility of amphibian calls? Singapore provides an ideal field setting to address this question. Prospects for acoustic ecology are currently bright because advances in computer storage technology and classification algorithms are making previously infeasible data-intensive methods available to researchers. In automated acoustic monitoring, calls collected remotely are automatically classified to species facilitating long-term monitoring of amphibian species. The survey stations can also automatically collect abiotic data such as temperature and humidity to study the effects of these on amphibian calling behavior and population dynamics. The stations are thereby able to provide long-term information on population fluctuations, including effects of naturalised species on native amphibians, and can thereby provide necessary information on management actions.
The overall aim of this research is to assess amphibian population dynamics in Singapore by establishing a pilot study of the acoustic landscape in five semi-natural to natural areas. The data will be used to assess 1) the effect of habitat structure on the audibility of amphibian calls; 2) estimate the occupancy of endangered and naturalised amphibians.
This project is funded by Wildlife Reserves Singapore Conservation Fund: