Batty about Bats
With the aligning of Easter, Ramadan and Passover on the Bank Holiday weekend, you might have missed that April the 17th was Bat Appreciation Day! We appreciate bats every day at Heath Hands, and we recently discovered more about them with Cindy, a Chiropterist (bat expert) and Wood Keeper at Highgate Wood.
Loved or misunderstood, there’s no denying bats are brilliant! Furry as they are fascinating, these unique flying mammals are also extremely useful to have hanging around (pun intended) and their presence (or absence) provides indicators of ecosystem health. Eight different species of bat have been recorded in Highgate Wood and the nearby disused railway tunnels (Common Pipistrelle, Soprano Pipistrelle, Nathusius’ pipistrelle, Natterer’s, Daubenton’s, Leisler’s, Noctule and Brown Long-eared).
Cindy searches for hibernating bats in ‘bat alley’
In the UK, all 18 species of bat are insectivorous and are to be appreciated for their voracious appetite for pest insects. A single Pipistrelle weighing just 8 grams can eat up to 3,000 insects in one night!
Most species of bat in the UK have evolved to live in tree cavities, but bats will roost almost anywhere, providing the conditions are suitable for their needs. Natterers favour natural tree roosts, whilst Pipistrelles, Noctules and Leislers have all been happy to make use of some of the bat boxes put up in the wood by the Conservation Team. Heath Hands are also increasing roosting habitats for bats by putting up boxes on Hampstead Heath and nearby green spaces, funded by our Adopt a Wildlife Home scheme.
Leading us to an area of the wood she affectionately calls ‘bat alley’, Cindy points out the many and varied designs of bat boxes on some of the old oak trees. Taking a camera, she zooms in on a couple of the boxes and shows us what’s inside (Note: it is a criminal offence to intentionally disturb a bat unless you hold a special licence). Much to everyone’s delight, the first box reveals two hibernating golden-brown Noctules, the UK’s largest species of bat. Six tiny Common Pipistrelles (conversely, one of the UK’s smallest species) were snuggled together in the second. See pictures below.
Two Noctules in a bat box. Thanks to Tim Harrison for the great photo!
Six Pipistrelles huddled together in one of the newer bat boxes
Entrance to one of Highgate’s disused railway tunnels
To the bat cave!
Checking the bat boxes and tree cavities around the wood is exciting enough, but as a licensed bat ecologist, Cindy also surveys bat inside Highgate’s disused railway tunnels – aka the ‘bat caves’. Ecologists have been monitoring the otherwise inaccessible protected tunnels for several years, and each year the number has steadily increased to a record 44 bats last January. Most of these were Natterer’s, Daubenton’s and brown long-eared making use of bat bricks and boxes that have been installed. Spotting them can be tricky inside tiny crevices, underneath wall fittings, and behind the black crusts of carbon deposits left on the walls by the old steam trains.
But now the nights are getting warmer, hungry bats are beginning to come out of hibernation in search of food – and spotting them is easier than you might think. The next time you’re enjoying an evening BBQ in the garden, or a dusk walk on Hampstead Heath look up above between the tree clearings and you might just spot a brilliant bat or two yourself!
This Daubenton’s bat has secreted itself behind a crusty carbon deposit on the tunnel wall
If you enjoyed this blog and you’d like to help Heath Hands’ conservation efforts, why not adopt a bat home made by our dedicated volunteers? And if you want to show your support for bats, you can now buy a Hampstead Heath bat tote bag to support our conservation work.
