In Britain's ancient forests, where the night silence is broken only by the echo of wings, scientists have for the first time heard the voices of millions of bats — and not without the help of artificial intelligence. Over three years, 98 million echolocation signals were recorded in 310 woodlands across the country. Without AI, processing such a volume of data would have taken more than thirty years.
The study, conducted by the Bat Conservation Trust and Forestry England with the support of University College London, became the largest acoustic survey of bats in the country's forests. Devices mounted on poles recorded sounds over 9734 nights from 2021 to 2024, creating 217 terabytes of recordings. Open AI algorithms made it possible not only to identify species but also to reveal patterns at the national level.
The findings concerning rare species proved especially important. The red-listed barbastelle (Barbastella barbastellus) and the grey long-eared bat were recorded in the southwestern counties — Somerset, Devon, Cornwall and Dorset. These are precisely where the "hotspots" of activity of these elusive inhabitants of old forests are concentrated. The survey covered almost all species of British bats except one that is difficult to identify.
Such data change our understanding of the role forests play in the lives of bats. The activity of common and soprano pipistrelles proved higher in the west, and broadleaved woodlands on the whole proved preferable. For seven rare species, including horseshoe bats and long-eared bats, this is so far the only national study outside known habitats.
The scientists emphasise that AI did not merely speed up the work but opened up a fundamentally new scale of monitoring. "Artificial intelligence has fundamentally changed the possibilities for observing wildlife," notes Kate Jones of UCL. The project is being called "a good story about AI for good" — a technology that helps us understand where and how to preserve fragile ecosystems.
The results show how valuable old forests are for rare species and how important it is to continue such observations in order to notice changes in populations in time.
