Working with a network of volunteers, static acoustic bat detectors were deployed in 2024, to provide data on bat distribution and activity for the Skell Valley. This report provides an overview of the survey coverage and results from the project.

Coverage: In 2024, 66 different locations across the Skell Valley were surveyed. Recording was undertaken on a minimum of 155 different nights mainly between April and mid-August, amounting to a total of 295 nights of recording effort across sites. Sound recordings were uploaded by volunteers or National Trust staff to the BTO Acoustic Pipeline, through which a first automated analyses was carried out and provisional results returned. Recordings were then moved to deep glacial storage for later auditing. At the end of the survey season, a copy of the recordings were pulled back and manual auditing of the results / recordings carried out.

Results: Overall, 228,254 recordings were collected over the project which, following analyses and validation, were found to include 130,460 bat recordings, and 202 small terrestrial mammal recordings. Audible moth species were also recorded as ‘by-catch’, for which we report species presence on a site and night basis. Following validation, the study confirmed the presence of at least 7 bat species, 4 small mammal species, species of 2 audible moth species. Through this project, we have significantly improved our understanding of the status of all species of bats within the Skell Valley, and of the relative importance of different areas. Lastly, the project provides data on the distribution and activity of several species of small terrestrial mammals. The report includes a full species-byspecies breakdown of spatial, seasonal, and through-the-night patterns of activity.