Unique tarsiers face threat from people's misperception

Unique tarsiers face threat from people's misperception

Myron Shekelle, Research Associate, Center for Biodiversity
and Conservation Studies, University of Indonesia, Jakarta

Tarsiers are charismatic nocturnal primates. In Indonesia, they
are found on Sulawesi, Borneo and Southern Sumatra as well as
some other smaller islands. Most experts now consider any reports
that tarsiers once existed on Java to be erroneous.

An adult male tarsier weighs about 125 grams and a female's
weight averages about 90 percent that of males. Tarsiers have a
tail that is about 25 centimeters long and their body is about
half that length.

Tarsiers are exceptional in many ways. Their huge eyes are the
largest of any mammal, relative to their body size. Pregnancy
lasts six months -- an exceptionally long period for such a small
animal, and the newborn tarsier may weigh 33 percent as much as
its mother, also the largest for any mammal. That would be like a
50 kilogram woman giving birth to a 17 kg baby (imagine giving
birth to a three-year-old human)! Once tarsiers are born they
develop very quickly, however, and it is believed that they reach
sexual maturity between 18 years and 24 years of age.

Tarsiers are arboreal, but they do not move through the trees
like monkeys and squirrels, which run and climb with four legs
quadrupedally. Tarsiers are known as vertical clingers and
leapers, and this small animal that is about the size of a gerbil
routinely makes leaps that are greater than three meters. To
accomplish this, tarsiers evolved long legs that are twice as
long as their arms and greatly extended ankle bones -- called
tarsal bones (from which they get their name), which gives them
an extra joint in their legs. This, in turn, gives them the
ability to make powerful leaps.

With this ability for leaping, they propel themselves from
sapling to sapling, almost as if they were flying through the
understory of the forest. In fact, the first scientific study of
tarsiers came in the late 1960s when an ornithologist working in
Sarawak found his mist nets getting tangled up with tarsiers.
Since then there have been many scientific studies of tarsiers in
the wild that use mist nets to trap and survey wild tarsiers.

On Sulawesi, tarsiers are a major lure for adventure tourists
who wish to see this beautiful and interesting animal in its
natural setting at places like Tangkoko Nature Reserve in North
Sulawesi and Lore Lindu National Park in Central Sulawesi.

Unfortunately, some people like to take these animals home as
pets. Although tarsiers are protected under Indonesian and
international law, they can often be found for sale in Jakarta at
Pasar Pramuka and Blok M. In some places, such as parts of North
Sulawesi, capture for the pet trade is thought to be a major
threat to tarsier populations. This is doubly sad because
tarsiers do not do well in captivity and even the finest zoos in
America and Europe have failed to establish tarsier breeding
colonies in captivity. Most captive tarsiers will die within a
few weeks of being taken from the wild.

Another problem facing tarsiers is the misperception by
farmers that tarsiers eat crops. This is a trend found throughout
Sulawesi, with coconut farmers claiming that the tarsiers eat
coconuts, chocolate farmers claiming they eat chocolate and corn
farmers swearing that tarsiers eat corn.

Correcting this misperception has proven to be a challenge
since indigenous people are more inclined to trust their folk
beliefs than modern science. In fact, tarsiers are the only
primate in the world that do not eat any vegetable matter. They
are 100 percent faunivorous, eating only live-caught animals --
mostly insects like crickets and grasshoppers.

Conservation of wild tarsier populations is entirely
consistent with local agricultural practices. In yet another sad
irony for tarsier conservation, tarsiers should be good, if
anything, for farmers because they eat crop pests, but farmers
will sometimes eradicate them because of their false folk
beliefs.

Tarsiers from Sulawesi are also interesting to scientists
because it appears that they have speciated on Sulawesi.

Currently, scientists recognize five species from Sulawesi,
including the Tarsius spectrum from near Makassar, South
Sulawesi. The Tarsius dianae is from Lore Lindu National Park and
other parts of Central Sulawesi, while T. pumilus is a pygmy form
of tarsier from the mountaintops of the central part of Sulawesi.
There are two species from offshore islands: T. sangirensis from
Pulau Sangihe Besar, North Sulawesi and T. pelengensis from
Peleng island, Central Sulawesi. Scientists have evidence that
there may be 14 or more species of tarsiers on Sulawesi, but this
theory needs verification, and they are studying DNA from wild
tarsiers to test that idea.

Habitat loss is a major problem in Sulawesi, but tarsiers live
in a broad variety of habitats and the tarsiers of Sulawesi, as a
whole, are probably not in imminent danger of extinction.

Nevertheless, some populations are probably at risk and
because some tarsier species have not even been identified yet,
there is the sad possibility that some species could go extinct
before they have even been named. One such possibility is in the
Togian islands of Central Sulawesi. Scientists from Germany and
the United States working with Indonesians have discovered that
the Togian tarsiers are probably a new species, but habitat loss
caused by logging is unchecked there and many species are
threatened.

To lessen the risk that some tarsier species go extinct,
scientists and conservationists from Indonesia and abroad are
working hard to overcome the misperceptions -- some of which are
repeated in the mass media -- that threaten tarsiers. First,
tarsiers do not make good pets. They are very cute, but they have
a vicious bite, do not like to be handled and do not live very
long in captivity. Second, tarsiers do very well in kebun
(plantation) habitats if they are left alone. They may even help
farmers control insect pests and they certainly will not eat farm
crops.

Since tarsiers do not keep well in zoos, one of the very few
places in the world where they are on public display is at Taman
Safari park in Cisarua, Bogor, about an hour's drive from
Jakarta.

Like in the movie Gremlins, tarsiers are photogenic animals
that are sometimes in demand as pets, but they have the sharp
teeth of a meat eater and can deliver a vicious bite.