There are around six species of bat in the UK, that have a strong association with woodlands that have plenty of veteran trees and those with hollows, cracks, old woodpecker holes, rot points and or loose bark. Bats will move their roost sites often in order to cope with parasite loads, colony growth and temperature change, consequently bats require a range of deadwood options within and around woodland.
I am going to write about brown long-eared bats, as one was recently found and rescued within Revesby Estate. They favour woodland with a closed canopy and a good thick understory with lots of shrubbery and brambles. They rarely fly over open ground and will move along hedgerows, tree lines and woodland edges to find foraging ground away from a roost site.
Brown Long-eared bats have very large ears as their name suggests. They are thought to be able to use these ears to hear the movement of small insects and one of the ways they feed is to fly close to vegetation picking off beetles, spiders, crickets and moths directly from the leaves, this is known as gleaning. Like other bats, they will also use echolocation to find insects on the wing, they make clicking sounds as they fly and listen out for the echoes of those clicks to locate insects such as moths in front of them. We can only hear these clicks by using a bat detector.
The larger ears mean that brown long-eared bats can use much quieter echolocation clicks than other bats. This can benefit them as it is thought that some moths are actually able to hear bats echolocating and take evasive action!
Brown-long eared bats will also roost and forage around buildings but only where they are in darkness, they are actively deterred by lighting – unlike bat such as pipistrelle species which will come and pick off insects around a light. If ever you have found a little pile of moth wings in your porch or shed, it is likely that a long-eared bat uses that space at night, as a place to hang up and eat larger insects that are tricky to handle in flight.
Should you ever encounter a brown long-eared bat roosting you may feel quite confused when you can hardly see any ears at all, this is because they fold their ears down when asleep and keep them tucked under their wings to stay warm.
This is the time of year when bats can get into difficulty as the young ones try to learn to navigate and find food and the adults are exhausted. It has been a very poor year for insect numbers and bats are struggling. If you find a grounded bat, or one which looks like it is in trouble, wear some gloves and place it in a dark box (a shoebox is ok with a few airholes) and contact the National Bat Helpline on 0345 1300 228 or if you are in Lincolnshire 07713 760211 or 01754 880070
Gillian Fisher, Ecologist
Bat Advice
