AI sorts 98 million bat calls in England's largest woodland bat survey

The National Woodland Bat Survey, led by Bat Conservation Trust and Forest Research and funded by the UK government through Defra, recorded 9,734 nights of audio at 310 English woodland sites between 2021 and 2024, 217 terabytes or about 90,000 hours, and AI tools developed with researchers at UCL and the University of Edinburgh detected more than 98 million bat calls in it, UCL said Oct. 30. A subset of the AI identifications was checked by 19 expert verifiers from the trust’s Verifier Network. The survey detected every British bat species or species group except the serotine, including the UK Red List grey long-eared bat and barbastelle, recorded barbastelles in parts of Cornwall, Devon and Dorset with few previous records, and is the only active national-scale monitoring in England of any kind for barbastelle, Leisler’s bat and Nathusius’ pipistrelle.