Bats and moths share a close, though
perhaps rather one-sided relationship. As predator and prey they
have evolved closely. Bats are able to navigate using a sophisticated
sonar system called echolocation. Sound waves are emitted by bats
and detected as they bounce back from objects or potential prey,
creating a detailed ‘picture’ of the bat’s environment,
which is essential in navigation and hunting for prey. Though bats
are top predators some moths have developed simple hearing organs
that can pick up on echolocation, allowing evasive action to be
taken, whilst the tiger moths are able to emit loud clicks similar
to echolocation calls, which are thought to confuse bats. All of
the 16 species of bat resident in Britain are known to feed on moths,
but the two British species of long-eared bat Plecotus
spp., the two horseshoe bats Rhinolophus spp., Barbastelle
Barbastella barbastellus and Bechstein’s Bat Myotis
bechsteinii are particularly partial to moths, which form a
significant part of their diet.
Bats and moths are under pressure from similar changes in our countryside,
and the declining numbers of insects is inevitably going to impact
upon the bats which feed upon them, so it is in the interests of
bat workers and moth recorders to work together in highlighting
the problems faced by both.
Some interesting facts about bats:
- Bats are the only mammals in the world capable of powered flight.
- There are 17 species of bats resident in the UK, representing
almost a third of all our mammal species.
- Britain's commonest bat (the pipistrelle) weighs in at just
5g, which is less than a £1 coin.
- Bats can live up to 30 years.
- In winter, when there are few insects around bats hibernate
in the cool parts of buildings, caves
or hollow trees.
- Bats are not blind and can see perfectly well by daylight, as
we do.
- The Brown long-eared bat has exceptionally sensitive hearing
and can hear a beetle walking on a leaf.
- Bat populations have declined so dramatically in the UK –
largely due to habitat loss - that all bats are protected by law
and the Bat Conservation Trust is the only national organisation
solely devoted to the conservation of bats and their habitats.
- With the help of thousands of volunteers the Bat Conservation
Trust annually surveys bats across the UK for the National
Bat Monitoring Programme to tell us how bats are faring.
The charity also has an online
Big Bat Map which enables the general public to log
their sightings of bats that they see in their garden or local
park, and look up what bats have been seen in their local area.
For further information about bats and how you can help in their
conservation visit the Bat Conservation Trust website
www.bats.org.uk
Some key facts about moths:
- More than 2500 species of moth have been recorded in Britain
and the Channel Islands. Moths have a wide diversity of bright
colours to warn away predators and cryptic camouflage to avoid
predation.
- Moths are important in the environment. They pollinate plants
and are a source of food for many other creatures, including bats
and most garden birds.
- Moths are artificially divided into the macro-Lepidoptera (larger
moths) and micro-Lepidoptera (smaller moths), although in practice
some of the micro-Lepidoptera are larger than the
macro-Lepidoptera!
- The difference between a moth and a butterfly is not always
a simple one, as there are exceptions to the rules. Not
all moths fly at night, for instance. However, generally speaking
butterflies have clubbed antennae whilst the vast majority
of moths do not.
- Many moth species are declining as a result of changes within
our countryside and climate change. 62 moth species became extinct
in Britain during the twentieth century and the total abundance
of moths has decreased by a third since the late 1960s.
- Some of the species that arrive within our shores have travelled
from Europe or even North Africa. Some come here every year and
breed successfully whilst others are rare vagrants. In recent
years an increasing number of species from Continental Europe
appear to be colonising Britain.
- It is a common misconception that moths eat clothes. In fact
it is only the larval stage of two common species of moth that
are known to feed upon clothing.
- The study of moths has long tradition in Britain and Ireland
and is growing rapidly in popularity. The
National Moth Recording Scheme, set up recently by Butterfly
Conservation, has gathered millions of modern and historical moth
sightings from members of the public. This information will be
used to identify species in decline and to underpin conservation
initiatives.
Leaflets about bats, moths and NMN are available on request by
phone (01929 406009) or email nmrs@butterfly-conservation.org
|