Coldfall Wood hosts a lot of bats.
Our latest bat survey was carried out in October 2013. We found one Leisler’s and 16 pipistrelles (including two mating pipistrelles) in the bat boxes, as well as lots of droppings that indicate other boxes are also in use.
Leisler’s bats (Nyctalus leisleri) weigh 12 to 20 grams and have a wingspan of 26 to 32 cm.
Leisler’s bat is naturally a forest species, roosting in tree holes. Bat boxes have proved a useful substitute for natural roost sites. They occasionally share roosts with noctules and pipistrelles. They tend to be nomadic, occupying a roost for only a few days before the colony moves to another roost.
They appear early in the evening and may stay away from the roost until dawn. They are very vocal prior to emergence and are particularly noisy on hot summer days, producing a loud metallic sounding call.
They usually fly high and fast in the open, frequently at or below tree top level, with shallow dives. They may be attracted to insects around street lights.