07 May 2021 Detecting and monitoring bat roosts through innovative new technology
BSG Ecology’s Principal Ecologist Gareth Lang has developed a motion-sensitive infrared camera responsive enough to detect and monitor bat roosts. The camera has been designed to allow for more effective recording of bats emerging from or re-entering roosts than off-the-shelf trail cameras currently achieve. The ‘BatCam’ records footage continuously but is programmed to capture and store footage immediately before and after it is triggered by motion to ensure that rapid action events (such as emerging bats) are fully recorded. Over the winter we have been working hard to refine the camera. We have now added the ability to remotely activate the camera and download video on the ground; this is particularly useful when monitoring bat roosting features in trees as it negates the need for more than two climbs during long-term monitoring. We will continue to test the ‘BatCam’ in spring and summer 2021.
This footage of Bechstein’s bats captured by the camera provides a very clear example of its benefits in achieving more robust survey results. The camera was installed on 2 September 2020 and recorded for ten nights. On the first few nights no bats used the tree for roosting (so nothing would have been detected on a standard emergence / re-entry and no bats would have been present (although signs of previous use could have been detected) during a climbed inspection). Over the following nights bats were seen landing on the tree close to the entrance hole. Subsequently they used the tree in excellent numbers, with 37 roosting in it on 8 September and a peak of 39 bats present on 9 September. A perfect illustration of the transient use of tree roosts and how hit and miss standard ‘snapshot’ surveys of tree roost features can be.
The work continues to be led by Gareth Lang with the sponsorship of BSG.