Bat Survey Season 2024
With night time temperatures still very low, its likely that breeding will be a little later this year, as bats respond to a low prey availability. Our busy season usually starts in mid-May, and we have lined up a good team of surveyors for the season. The 4th Edition of the Bat Survey Guidelines is now published and there are some welcome changes. One such is the removal of the stipulation for dawn surveys – when your surveyors are out 3 nights a week, and have to write reports all day, a 3am start is not good for anyone. We may still use them for bat species which are hard to detect at night due to late emergence, such as Natterer’s bats and brown long-eared bats, but it’s no longer required for a full assessment. There is also an increased acceptance of the use of infrared cameras with unmanned detectors to replace a surveyor position – the footage can then be analysed the next day, so we can make use of surveyors who are not available at night – though 2 hours of watching grainy footage for bat emergences may not be everyone’s idea of fun. Improved motion detection software will be the next advance in this technique – at present it doesnt work well for bats at night and manual analysis remains the only way to go.