By Glenn Norris
I will never forget the first time I heard the echo-locating calls of Common Pipistrelles along the Water of Leith in Edinburgh. Ten years on I still get a buzz when I’m listening in on their private conversations as they search for love and food; two of the highest priorities in our natural world.
Since then I have tracked Leisler’s Bats through the Ayrshire countryside and investigated the roosts of Horseshoe Bats in the West Country… but what about bats in Sussex?
All 17 species of bat that breed in the UK can be found in Sussex and 15 of these have been recorded on Sussex Wildlife Trust reserves. Most notable is the annual presence of the 18th British bat, the Greater Mouse-eared Bat hibernating in a disused train tunnel. Considered extinct in Britain since the 1990s this individual was first seen again in 2002 and has been recorded in the same tunnel every winter since. Where it goes for the summer, we have no idea.
Being a small bodied animal and using an enormous amount of energy to fly, bats feed heavily during the night; a Common Pipistrelle can feed on thousands of tiny midges in one night. For this reason, bats indicate the presence of healthy invertebrate-rich habitats. To avoid conflict, different species have evolved to feed on different prey at different times and amongst different habitats. Daubenton’s Bat have large feet for picking up insects off the surface of the water whereas the large Noctule catches moths flying over 5m.
The best Sussex Wildlife Trust nature reserve for bats is Ebernoe Common.
This ancient woodland and pasture has records for 15 UK bat species, including internationally important breeding populations of Bechstein’s Bat and Barbastelle, and provides the wide range of their habitat requirements in one location. Bats need different habitats throughout the year; they often roost in warm trees and roof voids during the summer feeding amongst woodland, hedgerows and meadows, and then crave the cool stable temperatures found in caves and mines in winter.
Our nature reserves are vital beacons of high-quality habitat where bats have the opportunity to roost and forage during the summer, but the key to bat conservation is to create high-quality, linked-up habitats within the wider landscape. For example, Ebernoe Common and The Mens are very important reserves for bats, but the four miles of countryside between them is equally important so they can exploit additional food sources and meet other colonies.
The Sussex Wildlife Trust has seen the benefits of this landscape approach to nature conservation during the Butcherlands Project. This large area of ex-arable land has been left to develop using natural processes and conservation grazing. The result is a mosaic of grassland, scrub and some young trees full of invertebrates on which Barbastelles from the nearby Ebernoe Common are foraging. The crop fields there previously would not have provided as many invertebrates and would not have supported foraging bats as they do now.
These days, bat detectors are relatively inexpensive and easy to use, so pick one up, head outside just after sunset in a local park or woodland and dial in to the usually inaudible buzzes, clicks and whistles; if you’re lucky and you live in the right area, you may even hear the extra-terrestrial vocalisations of the rare Greater Horseshoe Bat, reminiscent of the 1970s kids TV show The Clangers.