Now that the weather has turned colder, most bats will have found their spot to hibernate for the winter. November is a good time to carry out a bat survey of your wood, when the leaves have dropped from the trees and it’s easier to see possible bat roosts.
Are there bats in your woodland? Almost certainly: most woodland, unless it is very young, will have bats roosting somewhere. Woodland provides the perfect habitat, from a stand of few trees to large woodlands. Clefts in branches, woodpecker or rot holes and loose bark make good roosting spots, and the insects that gather around trees provide food. Five British species are woodland specialists: Bechstein’s bat, the Barbastelle, the Natterer’s, the Noctule, the Lesser Horshoe and the Brown Long-eared bat.
There are some factors that increase the likelihood of there being roosts. Obviously, mature trees are more likely to provide the nooks and crannies that bats like. For the same reason, dead, standing trees are popular, or trees, young or old, with damage. Wind-thrown trees leaning up against one another are also good. Ivy and other dense climbers can give cover too. Hedgerows linking woodland areas are important as “traffic routes”, allowing bats and other creatures to move under cover. Derelict buildings, underground structures, drystone walls and bridges are all built features that can attract bats. And you can, of course, put up your own bat boxes.
Bats need a good source of food too. Water – ponds, streams, and ditches for example – encourages the insect population, as do shrubby wood edges and rides. In general, bats like a little bit of untidiness.
It is worth taking the time to do a walk-through survey. Bats and their roosts are protected and it is part of good woodland management to make allowances for them. All you will need are a pair of binoculars and a pencil and paper for notes. Look out for likely trees and make a note of them – you may be able to see black bat droppings underneath. They will not use one roost continuously, they move around, but once they have established a favoured spot they tend to return to it.
Comprehensive advice is available in the Forestry Commission’s booklet “Woodland Management for Bats” . The Bat Conservation Trust can also provide help and advice and run a Bat Helpline. If you should find a bat and think it’s injured, try to avoid picking it up unless you are wearing thick gloves – there is a very small risk of the bat carrying a rabies-related virus and they can bite. Best is to put something like a shoe box over the top of it and slide a piece of cardboard underneath. The BCT can usually put you in touch with someone locally who has experience in treating injured bats.