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The gardens, lakes and open woodlands of Wakehurst Place
coupled with the Loder Valley Reserve provide a perfect habitat
for bats. As many as eight species have been sighted here.
With almost 1000 species, bats represent one of the most
successful groups of mammals. For their size, bats are amazingly
long lived with life-spans of around 30 years not unknown.
They are found throughout the world, although the majority
live in the tropics. Thirty species are found in Europe and
of these sixteen occur in Britain. Unfortunately nearly all
species are now in steady decline due to human pressures on
the environment.
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| Above: Daubentons’s Bat (Myotis
daubentonii) in flight, low over water |
Bats are the only mammals capable of sustained flight and
most fly and hunt between dusk and dawn. Contrary to popular
belief, bats are not blind although in complete darkness eyesight
is useless. To overcome this problem bats have developed a
form of sonar which enables them to hunt for prey and avoid
obstacles at night. Bats achieve this by emitting a series
of high-pitched squeaks which bounce off obstacles. By listening
to the returning echoes they piece together an image of their
surroundings.
Three-quarters of the world’s bats are insectivores
and it is estimated a single bat can consume over 3000 insects
each night. About 5 per cent of species are carnivorous, eating
mice, lizards, fish, frogs and even other bats. Three species
confined to South America feed on blood; these are the infamous
vampire bats. The remaining species are vegetarian, feeding
on fruits and flowers. These species play a vital role in
maintaining the rich ecosystems of tropical rainforests with
many trees dependent on bats for pollination and seed dispersal.
The great success of bats globally is in part due to their
diversity of feeding strategies. This is readily observed
at Wakehurst Place. The noctule flies high above Horsebridge
Wood hunting for large insects such as the armour-plated cockchafer.
The brown long-eared bat can be found foraging amongst the
trees of the birch collections in Bethlehem Woods. The abundance
of insects around the lake in Westwood Valley attracts the
highest concentration of bats, including the Daubenton’s
bat that hunts for prey just above the water surface.
As autumn approaches bats concentrate on increasing body
weight to provide crucial fat reserves required for their
winter hibernation. To help conserve energy at this time they
lower their body temperature and reduce their heart rate to
just a few beats per minute.
In this state of torpor bats are very vulnerable and any disturbance
will reduce their chances of survival. Within the gardens
most bats hibernate in trees but there are recordings of some
species hibernating in the deep crevices of sandstone rocks
along Rock Walk.
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The Great Storm in 1987 caused untold damage to the gardens
and woods at Wakehurst Place with the loss of thousands of
trees. As a result, many potential roosting sites were destroyed.
This has increased competition between hole-dwelling animals.
Consequently many bats are killed or driven from their roosts
each year by competing squirrels and starlings.
To help alleviate this problem, staff at Wakehurst Place have
begun to construct artificial roost sites. These recreate,
as accurately as possible, the natural conditions of a tree
cavity which are essential for the establishment of large
breeding colonies. By inspecting the roosts each year we hope
to increase our knowledge of bat populations at Wakehurst
Place and ensure that our management of the estate helps conserve
these fascinating creatures.
There are sixteen species of British bats, all insectivores,
which belong to two families, the vesper or evening bats and
the horseshoe bats. There are fourteen vesper bats including
the noctule, a large and powerful flyer, and the Bechstein’s
bat, one of Britain’s rarest mammals. The two remaining
species are the greater and lesser horseshoe bats, both of
which are very rare and confined to the south west of Britain.
| Pipistrelle 45Kh |
Small |
Very common |
| Pipistrelle 55Kh |
Small |
Very common |
| Brown long-eared bat |
Medium |
Very common |
| Noctule |
Large |
Common |
| Daubenton’s bat |
Medium |
Widespread |
| Whiskered bat |
Small |
Widespread |
| Brandt’s bat |
Small |
Widespread |
| Serotine |
Large |
Confined to South |
| Natterer’s bat |
Medium |
Uncommon |
| Leisler’s bat |
Medium |
Uncommon |
| Nathusius pipistrelle |
Small |
Regular migrant |
| Lesser horseshoe bat |
Small |
Rare |
| Barbastelle |
Medium |
Rare |
| Grey long-eared bat |
Medium |
Very rare |
| Greater horseshoe bat |
Large |
Very rare |
| Bechstein’s bat |
Medium |
Very rare |
| Mouse-eared bat |
Large |
Extinct in Britain |
Species in bold print are seen at Wakehurst.
To help prevent any further declines in populations all bats
are protected under the Wildlife and Countryside Act 1981.
This law states it is an offence to intentionally:
• kill, injure or handle bats
• possess a bat whether dead or alive
• disturb a bat when roosting
• destroy or obstruct a roost
• sell, barter or exchange bats
If any work is planned that might affect a colony of bats
or a roost site, English Nature must first be consulted. They
will advise on the best course of action to minimise disturbance.
The law does, however, allow bats to be caught and then released
if found in the living area of a house and for the treatment
of sick bats.
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