Balcombe’s rich ancient woodlands, arable land, and lake provide great foraging and roosting habitat for a range of UK bat species. The United Kingdom has 18 species of resident bat species, all of which receive strict legal protection. Bats are excellent indicators of a healthy ecosystem; therefore, the Balcombe Ecological Society conducts systematic bat monitoring across the Parish from spring through autumn. All surveys follow the Bat Conservation Trust Good Practice Guidelines and contribute directly to local and national datasets.

Survey Methodologies

We use non-invasive survey methods to map seasonal activity across the parish.

Walked Activity Transects

These surveys start at sunset and can continue for up to two hours after dusk. Our survey team walk fixed, repeatable transect routes along woodland edges, hedgerows, and riparian habitats. The purpose of these surveys is to map commuting routes and identify key foraging hotspots. We use a range of equipment for these surveys, such as handheld full-spectrum detectors and heterodyne detectors.

Static Acoustic Monitoring

We use static acoustic devices for long-term, weatherproof monitoring. These detectors are deployed along treelines, streams, fields, and in woodlands. Static detectors provide a huge advantage as they collate continuous, undisturbed data throughout the entire night.

Bioacoustic Analysis and Verification

Bats navigate and hunt in the dark using echolocation. Different species have distinct call structures, peak frequencies, and characteristics. To ensure accuracy before submitting records, all full-spectrum audio files recorded by the society undergo a two-stage verification process
1. Audio recordings are processed through the BTO Acoustic Pipeline to generate initial statistical species probabilities.
2. All automated identifications are manually inspected on spectrograms using Kaleidoscope to verify call parameters.
Once verified, records are logged in the Balcombe Parish Biological Database (VC14) and shared with the Sussex Biodiversity Recording Centre and the National Biodiversity Network Atlas.
Please note that roost locations will not be shared with the public and will be generalised for data submission.