This data gives acoustic index values for recordings collected in 60 broadleaved woodland restoration sites in Central Scotland (n=30) and the English Midlands (n=30), as well as 18 grassland sites in southern England. Additionally, there are recordings from 6 wildcard sites, made up of ancient woodlands (2 in Scotland and 2 in England) and rewilding sites (2 in England). There were three deployments of acoustic recorders between July 2021 and April 2022. Full details about this dataset can be found at https://doi.org/10.5285/33b6dea2-94c5-4e33-a1b3-9a6bd1c8776a
