Bats, No Durians
Part 1 | Part 2
The fruit bat is
an important pollinator and seed dispenser and traditional farmers in Malaysia
know that one of the species, the Dawn bat, is a very effective pollinator
of durian flowers which is why they say, 'No Bats, No Durians'. Yet this
harmless creature has been hunted for its flesh, for sport and even as a
crop pest! Lim Gaik Kee from Sahabat
Alam Malaysia (SAM) wrote this article for Malaysia's Utusan Konsumer to
wake us up to what wantonly destroying this small mammal could mean to our
forests and fruit orchards. (Naturewatch has adapted this article for its
readers and credits the author and Utusan Konsumer for their research and
their views.) Photographs by Lee King Li
(unless otherwise stated).
are a highly priced and relished fruit and yet few people give any
thought as to how the durian flower develops into thorny fruits that
conceal the most delectable creamy pulp-covered seeds. Yes, for the
durian and other jungle and orchard fruits and even beans (like petai)
to be pollinated, the fruit bat is indispensable. In fact all bats
are friends of nature and of man yet this flying mammal is a much
misunderstood, unappreciated and even feared creature. Most of us
know of bats only as rat-like creatures with wings and our encounters
with these animals are most likely to occur only when we explore caves
and come across them either swarming out of the cave or massed inside
the cave where they can be seen hanging upside down and producing
tons of excrement, 'guano' which is distinctively smelly.
But bats are in fact fascinating nocturnal creatures with warm bodies
and soft fur. They usually shun daylight and if seen at all outside
of caves it is normally only at twilight where their forms appear
as silhouettes zigzagging across the darkening sky. To appreciate
these much maligned little creatures, we have to look at the many
positive roles they play.
Firstly, bats of the Megachiroptera group, i.e., the fruit-eating
species, are, along with birds and monkeys, among the most important
seed-dispersing animals in tropical rainforests. These fruit bats,
together with nectar-eating bats, are also the creatures responsible
for the pollination of tropical and subtropical trees and shrubs.
And where the durian tree is concerned, it is the Dawn bat or Cave
Nectar Bat (Eonycteris spelaea) that is the only effective pollinator
of its flower. (These are the findings of Dr Marty Fujita from Boston
The durian's large creamy flowers are clustered on the underside of
its sturdy branches and very accessible to bats. Dawn bats are drawn
to the copious amounts of fragrant nectar exuded by the Durian's night
blooming flowers. No wonder there is a popular local saying, 'No bats,
no durians'. Every year, durian lovers, can look forward to some bountiful
crops on our island of Pulau Ubin as Durian Bats have been found there.
Another crop that relies on fruit bats for pollination, again according
to Dr Fujita, is the petai, a popular bean (Parkia speciosa and P.
javanica) sold in Malaysian markets and served as a vegetable in restaurants.
This bean comes from a large leguminous tree whose blooms are light-bulb
shaped and suspended from pendulous stalks. Like the durian flower,
the petai flower is easily accessed by the fruit bat.
Another very valuable tree whose propagation depends on bats is the
Sonneratia. The Sonneratia is a very important tree because it protects
the whole ecosystem of the mangrove against tidal and wave action.
Moreover, wood from these trees was traditionally and are still harvested
to be used as poles, furniture, footwear (sandals) and also to be
converted to charcoal. The bats that are responsible for pollination
are the Dawn Bat, the Long-tongued Nectar Bat (Macroglossus minimus)
and the Short-nosed Fruit Bat (Cynopterus brachyotis).
But these are not the largest of the bats found in mangrove forests.
In fact, two of the largest bats in the world roost in mangroves and
they are the Large Flying Fox (Pteropus vampyrus) and the Island
Flying Fox (Pteropus hypomelanus). The first bat was named
after vampires apparently because of its sinister appearance and nocturnal
habit, even though it is a frugivore. These large fruit bats have
a pointy snout making them resemble foxes which is why they are commonly
called flying foxes. In Sarawak the most prominent bat is the Cave
Besides their role as fruit pollinators, the other family, the insect-eating
bats of the Microchiroptera group are the most important controllers
of insects that prey on crops. Insect-eating bats aid in the biological
control of insect swarms that would otherwise devastate crops along
Sarawak's Baram and Tutoh rivers wrote Rambli Ahmad in the New Straits
Times (Oct 12, 1996). These Microchiroptera bats use echolocation
or sonar techniques for navigation as they hunt.
Short-nosed Fruit Bat
At night, this bat may be seen
visiting flowering or fruiting
wayside trees even right in
the heart of town
Singapore durian-lovers prize the
more delectable local varieties
like these growing on old trees
on the island of Pulau Ubin
Only several out of the whole
bunch of durian flowers will be
successfully pollinated to
develop into fruit
Glossy Horseshoe Bat
This is one of our smallest species.
An insectivore, it is important part
of the forest ecosystem as it keeps
insect populations in check
Dusky Fruit Bat
This bat was mist-netted for
studies and eventually released.
Researchers have found that this
species is an effective disperser
of seeds. Even its roosting areas
can be recognised by sprouting
seeds. Fortunately for us, small
colonies of this bat are still
found in Singapore forests.
Trefoil Horseshoe Bat
The intricate noseleaf structure
helps these bats to echolocate
and find their insect food
Cave Nectar Bat
This bat is being examined and
measured. Local bat researchers
are trying to find out more about
these beneficial creatures before
they go extinct in Singapore.
These bats roost in the open.
Many of these giant fruit bat species
are endangered world-wide, from
being hunted to loss of their habitats.
Rare in Singapore, those sighted
are most probably visitors from neighbouring countries
Photo by AT
Another example of insect eating bats that Rambli cited is the Philippines
Horseshoe Bat (Rhinolophus philippinensis). It appears that this
bat is even a choosy eater as it seems to feed only on the most succulent
and nutritious parts of the insect, namely its stomach. Rambli deduced this
when he came across a swarm of dead termites with all their abdomens missing
during one of his trips to the Mulu Caves area in Sarawak. The bats had
good reason to feast lightly too. They cannot fly well on a full stomach.
(Perhaps gluttonous humans should take a cue from the bat).
Because bats have up till now been among the least researched and therefore
least appreciated of mammals, we have not merely destroyed their habitats
by urbanisation and development but have actually hunted them as pests to
be exterminated! Perhaps our ignorance will haunt us as 'their death as
a species merely precedes our own..
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