Bat Facts
There can be few animals in the world that are as misunderstood as a bat. It's is probably because most people have had little contact with them except perhaps to see one or two flying in their gardens on a summers evening. Count Dracula has a lot to answer for when it comes to misconceptions about bats and their spooky image. Hopefully the following few facts will help to dispel some of the many myths. We welcome any of your questions and will try to include them in future updates
How many types of bat in the world?
There are about 1000 different species of bat in the world divided into two
groups. The smallest group are known as the fruit bats or megabats and
number about 170 species. This group includes the largest bats in the
world with wingspans up to 5 feet. As their name suggests they mainly eat
fruit or nectar from flowers. Fruit bats are only found in tropical places
across Africa, Asia and Australia. There are no fruit bats in the
Americas. The remaining 800+ species belong to a group called the micro
bats. Microbats are found all over the world except for the poles and have
a wide range of diets but the majority of them eat insects. A few species
feed on nectar, some catch fish and there are three species in Central and South
America that drink blood (the vampire bats). All British bats are micro
bats and eat only insects.
As blind as a bat
Not true, in fact bats have quite good eyesight, especially at
dusk. Fruit bats have large eyes which gather in a lot of light giving
them good night vision to find their food. Microbats, although possessing
reasonable eyesight from their much smaller eyes, have a much more efficient
method of finding their way in the dark called echolocation. They shout
extremely loudly, at frequencies too high for us to hear, and listen for the
returning echoes. The echo gives them all the information they need about
their surroundings and where their food is. It really is amazing that a
bat can locate, whilst flying, a tiny flying insect in total darkness.
Do they make a nest?
No, bats only use what is already there - caves, holes in trees, gaps in
bridges, roofs of buildings, external features of buildings eg. behind fascia
boards (a favourite roost site for pipistrelle bats). They do not make
existing gaps bigger, they don't chew cables in roofs, and they do not bring any
nesting material into the roost with them. Bats need different conditions
depending on the time of year. In summer female bats gather together to
form nursery roosts. To enable the young bats to develop quickly they need
a warm site such as a south facing gable or a roof space. Once the young
are able to fend for themselves they choose cooler sites to enable them to
conserve energy by slowing down their metabolism. In winter they need cool
sites with high humidity. Winter sites include caves, tunnels and old mine
workings.
How long do they live
Although many bats are tiny they can live for a surprisingly long time. If
they can survive their first winter they have a good chance of living for many
years. Although 5 or 6 years is usual for a pipistrelle some species may
live over 30 years.
How many babies do female bats have a year
Usually only one a year, twins are rare in Britain. It is a common
misconception that bats breed like mice and have large litters every few
weeks. Young bats are large and well developed at birth and can weigh up
to a third of its mothers body weight.
How big, and small, are British bats
Our most common bat, the pipistrelle, is also the smallest. It has
a wingspan of 19-25 cm, and weighs about 5grams. The noctule is our
biggest bat with a wingspan of 33-45 cm and weighs about 25 grams.
How can I encourage bats into my garden
Anything that can increase the insect population in a garden will make
it more wildlife friendly. Night scented plants which attract insects will
help as will a garden pond (no wildlife garden should be without one!).
What should I do if bats roost in my house.
Many people that have bat roosts are not aware that they are
present. Usual signs include droppings on window sills or on the ground
below access points. Bats do not make holes to get into roof spaces they
only use gaps that are already there. By far the most likely species to
use our houses, especially if your house is post war, is the pipistrelle.
Pipistrelle bats like to be in confined spaces and rarely venture into roof
spaces much preferring the smaller confines of soffits or those behind cladding
on the sides of buildings. If you have any concerns about bats in you
house or are planning work which may affect a bat roost please contact English
Nature for free advice. There are several regional offices covering all of
England, please see their website (link on our links page) for details. If
you are in Nottinghamshire the regional office is English Nature, Eastern Area
Team, East Midlands Region, The Maltings, Wharf Road, Grantham, Lincs, NG31
6BH. Tel: 01476 584 800 Fax: 01476 584 838; email:
east.midlands@english-nature.org.uk.
