Reports

The Bailiwick Bat Survey is a four year project and at the end of each year, BTO produce an annual summary report of the findings. The reports include a full species-by-species breakdown of spatial, seasonal and through-the-night patterns of activity. At the end of the four years, a final report will be produced. 

Read the results of the 2021 bailiwick Bat survey 

2021 Bailiwick Bat Survey Report

During 2021, 720,011 recordings were collected across the Bailiwick of Guernsey which, following analyses and validation, included 710,260 bat recordings, and 8,211 small terrestrial mammal recordings. Over 1.5 million recordings contained bush-crickets and audible moth species which were recorded as ‘by-catch’, and we report species presence on a site and night basis. 

Read the results of the 2022 bailiwick Bat survey 

2022 Bailiwick Bat Survey Report

During 2022, 622 different locations across the Bailiwick of Guernsey were surveyed. Recording was undertaken on 209 different nights mainly between April and the end of October, amounting to a total of 2,416 nights of recording effort across sites. 
 
Overall, 3,389,138 recordings were collected which, following analyses and validation, were found to include 872,126  bat recordings, and 8,587 small terrestrial mammal recordings. Over 2 million recordings of bush-crickets and audible moth species were also recorded as ‘by-catch’, for which we report species presence on a site and night basis.