Biggest library of bat sounds compiled

The biggest library of bat sounds has been compiled to identify bats from their calls in Mexico - a country which harbours many of the Earth's species and has one of the highest rates of extinction and habitat loss. An international team led by scientists from UCL, University of Cambridge and the Zoological Society of London (ZSL), developed the reference call library and a new way of classifying calls to accurately and quickly identify and differentiate between bat species. It is the first time automatic classification for bat calls has been attempted for a large variety of species, most of them previously noted as hard to identify acoustically. The researchers say the method can be used to monitor biodiversity change and complete information on bat species distributions in remote and understudied regions in Mexico. It could also be expanded for use in other areas across the Neotropics, which incorporates South and Central America, and the Caribbean Islands and Florida. "Audio surveys are increasingly used to monitor biodiversity change, and bats are especially useful for this as they are an important indicator species, contributing significantly to ecosystems as pollinators, seed dispersers and suppressors of insect populations. By tracking the sounds they use to explore their surroundings, we can characterise the bat communities in different regions in the long term and gauge the impact of rapid environmental change," explained lead author Dr Veronica Zamora-Gutierrez, from UCL and the University of Cambridge.  "Before now it was tricky to do as many bat species have very similar calls and differ in how well they can be detected.