Hibernation series: Bats

Bats typically enter hibernation in November and may not become fully active again until mid-May. During hibernation, bats lower their body temperature and metabolism, which allows them to use significantly less energy. This enables them to survive on fat reserves they've built up to make it through the cold winter months.

As autumn turns into winter, bats are on the lookout for a comfy roosting spot. They prefer small, cozy gaps, such as those found in mature or veteran trees hollowed out by decay or by other creatures such as woodpeckers. To keep warm during hibernation, bats will squeeze into tiny rock crevices and will roost in unusual positions, lying on their backs, sides, or heads!

The difference in a bat's heart rate between active and hibernation periods is astounding. While flying, a bat's heart can beat more than 1000 times per minute, but during hibernation, this slows to just 4 beats per minute.

The UK is home to 18 species of bats, with 16 species found in Devon. Our nature reserves are a haven for bats, with 14 species tracked at Seaton Wetlands and 13 at Knapp Copse, with similarly pleasing results from bat surveys at Holyford Woods.

This year, Seaton Wetlands became part of an exciting new research initiative. Our Countryside Ranger worked with Professor Fiona Mathews to install a Motus Wildlife Tracking System receiver, which is now gathering data for the England Bats Motus Project. This system tracks signals from radio-tagged bats, including the migratory Nathusius’ pipistrelle, which travels from the continent. Data from radio tag signals is logged at motus.org, contributing to valuable research on bat migration patterns.

If you spot a bat during winter, it may have woken from its hibernation for a quick snack or drink before going back to sleep.

Discover more about our conservation work by visiting: Nature Reserves (wildeastdevon.co.uk) and join our mailing list to be the first to hear about upcoming events such as summer Bat Walks.