Out with the bats

Date posted: 22/05/12

Tags: Discover Moorland , Moorland Life,

As sunset glowed into place, wildlife enthusiasts gathered at Simonsbath in the heart of Exmoor National Park, and waiting for them at the old water-powered sawmill were David and I, with a collection of special gear to help us spot bats. Red torches to help us all make the best of our natural night vision, and bat detectors to enable us to hear their ultrasound.

Our bat walk on 21st May was one of the new kinds of events in the 2012 Simonsbath Festival  - so we didn't know whether anyone would come! But we had a good turnout - and gladly the bats came out in force. (Cold weather last week had kept the bats hidden away.)

Let's go to the pub !

The landlord of the Exmoor Forest Inn kindly let us hang around and watch the bats fly out of the pub roof. What a great pub garden game! Wendy, one of our volunteers who had led a wildflower walk that afternoon, volunteered again to keep count of the emerging bats. Out they zoomed..! At first, only an occasional bat launched itself into the night air... but gradually we were watching an exciting flow of bat after bat after bat. The final count was 136 Common Pipistrelle.

A very short video clip!

Later on we heard lots of bats at nearby woodland, and watched dozens hunting at the River Barle. We hoped to see a few types of bat at Simonsbath - and we did! As well as the tiny Common Pipistrelle, we also spotted the big Noctule, and some mysterious others, which we think were 'Myotis' species.

Bat are amazing

About a quarter of British land mammal species are types of bat - there are 18 species in this country (maybe more, we aren't sure!). Each has their own specialist behaviours, but they are all insect-hunters. Bats are the only mammals that truly fly - and remarkable creatures in many other ways. They echolocate for a start! How fantastic is that? They are long-lived creatures, give birth to single or twin pups (perhaps a quarter of the mother's weight) and the young are nursed and ready to fly at 4 weeks of age. A bat's heartbeat can drop to 10 per minute when hibernating, with a body temperature only a few degrees above freezing. Yet when they fly, their temperature rises above anything a human could withstand.

Sound sample from my bat detector

Analysis of the sounds that we heard from the bat group hunting above the river suggest we were right to think that they were Common Pipistrelle. The peak frequency was 45 kHz.

Join us next time... we would love to set up a local Exmoor bat squad, linked to Devon and Somerset bat groups.

Jason Ball Scheme Manager, Exmoor Moorland Landscape Partnership.