Bats are highly specialised animals with some amazing features. They are the only true flying mammals and are long-lived, intelligent, and have complex social lives. There are at least nine species in Scotland, of which the most numerous and familiar are pipistrelles, which can be seen flitting about near woodland or open water at dusk, in search of midges and other flying insects. A single pipistrelle can consume up to 3,000 midges in one night!
Bats are essentially woodland animals, but as the availability of natural roosting sites in trees has declined and the number of warm, dry alternative sites in buildings has increased, so have these artificial sites become very important for many species. They have well established traditions and tend to return to the same sites, at the same time, year after year. If bats are present during the summer, it is often possible to see them fly out at dusk or even hear them inside the roost on hot days or before they emerge in the evening. Frequently, though, only signs of bats will be seen rather than the animals themselves. The most characteristic signs are their droppings which are composed of the indigestible remains of their insect prey. These are roughly the size and shape of mouse droppings but they crumble to a powder when dry and are usually found stuck to walls or in small piles below roosting bats or below the roost exit. There are three main types of roost:
- Buildings such as houses, churches, bridges, fortifications, schools etc. These are most important in summer, though some are used throughout the year.
- Caves, mines, cellars, ice-houses and tunnels. These are most important for hibernation as they give the sheltered and stable conditions that bats need during winter.
- Tree holes - used throughout the year.
An overview of the biology of the Scottish bat species can be found here.
How to get to know bats
Bats occur throughout Scotland, including many of the islands, although in Shetland they occur as vagrants only. In general, north of the Central Belt, the number of bat species living in an area decreases the further north and west you travel. The south of Scotland supports the greatest number of different species. Some are much rarer in Scotland than others, notably noctules, Leisler's, and whiskered bats which are all rare and have restricted ranges.
You can get a bat detector which makes the calls of your local bats audible to you and enables you to identify them. Your local bat group will help you obtain the best device and interpret the calls. They will also be pleased to hear about what you find in your area.
You should not handle bats if you are not properly trained - your local group can help with that too.
Threats to bats
Throughout Europe bats suffered a terrible decline in numbers during the 20th century, particularly since the 1960's with some species becoming locally extinct. As a result of these threats bats and their roosts are now strongly protected by law.
The reasons for the declines are likely to include: loss of suitable roosts, loss of foraging habitat, reduced availability of insect prey through the widespread use of pesticides in the countryside, and direct mortality of bats caused by the use of highly toxic timber treatment chemicals in house roosts. The use of approved, less-toxic compounds has significantly reduced the last threat in recent years.
What you can do for bats
You can buy or build bat boxes to encourage bats. These days many bats breed in our attics (because they are warm and dry). Please do not disturb them if that happens to you. Because they share our homes mainly to breed, they will vanish again in August or September. If they cause a problem, your local Scottish Natural Heritage office can provide advice.
Local bat groups have a vital role in the conservation process in Scotland. So if you want to help bats, get in touch with the Bat Conservation Trust (Scotland) or your local group.
Last updated on Friday 27th November 2015 at 10:24 AM. Click here to comment on this page