A research project looks at whether wildlife crossings work.
Source: myrimba.org
THE forest reserves around Tasik Kenyir in Terengganu teem with
wildlife. Aside from the 230 bird species which the area is known to
harbour, research group Rimba in recent surveys has recorded at least 19
mammal species in the area.
Their camera traps have captured
stunning images of various rare and endangered species. In one picture, a
female Asian elephant and her calf, their eyes shining in the flash of
the camera, are seen making their way through leaf litter. In other
images, tigers, sun bears, clouded leopards, tapirs and serows make up
more of the jungle milieu.
For most of these animals, a large
expanse of habitat is crucial for populations to remain viable in the
long term. But their habitats are being cut up by advancing development.
In addition to being a barrier for animals to reach resources such as
food, shelter and mates, isolated and fragmented habitats pose a threat
to the healthy mixing of populations. A genetically diverse pool of
individuals is needed to avoid the negative effects of inbreeding and
reduced genetic diversity.
Unfortunately habitat fragmentation is a problem in Malaysia, albeit
one that has, to an extent, been addressed by the Central Forest Spine
(CFS). Part of the National Physical Plan, the CFS is a masterplan which
delineates a network of forest complexes connected by ecological
linkages (corridors of forested land) to create a contiguous forest
running the length of Peninsular Malaysia.
The forests around
Tasik Kenyir, including the Hulu Temelong, Petuang and Tembat forest
reserves (in which Rimba researchers are surveying a 140sqkm stretch),
make up one such linkage. Known as Primary Linkage 7, this green
corridor links Taman Negara to forests in the north. The area is one of
three priority areas in the National Tiger Action Plan, a blueprint
document on the conservation of the big cat.
The reserves are
bisected by the Kuala Berang highway, which forms a dangerous barrier
for migrating wildlife. Intrusions such as this into the sanctity of our
wilderness are by no means unique and are a regular occurrence
worldwide.
Safe crossings
The trend of building
wildlife crossing structures began in the 1950s and is today a common
strategy deployed in many countries. Some of the most recognisable
structures were built in the 1970s in Banff National Park in Alberta,
Canada, where 24 vegetated overpasses provide safe passage over the
Trans-Canada Highway for bears, moose, wolves and many other species.
Crossings don’t have to pass over obstacles, however. In the
Netherlands, over 600 tunnels have been installed under major and minor
roads to aid in movements of the endangered European badger.
In
Malaysia, the Kuala Berang highway features 10 viaducts which offer
traffic-free crossing points for wildlife. Viaducts are elevated road
structures, typically passing over a valley or lower ground, and
supported by arches or columns. Three of these viaducts were built
specifically as wildlife crossing points, and have been termed
“eco-viaducts”. Unlike the vegetated overpasses in Alberta, safe passage
for wildlife in our viaducts lies with passing under the structure.
The
construction of eco-viaducts in Malaysia has been championed by
environmentalists as a promising measure but there have as yet been no
studies to confirm their effectiveness in the tropical context. The task
of verifying their usefulness is a huge undertaking and requires many
months of survey and data collection through thick forest, followed by
months of data analysis.
Nonetheless, having science to verify
the effectiveness of well-intentioned policy is important to ensure the
best solutions for protecting Malaysia’s valuable stocks of
biodiversity. That is precisely the thinking behind Rimba, a coalition
of local and foreign scientists, which has embarked on a project to
monitor the use of wildlife crossings along the Kuala Berang highway.
Country-specific solutions
The combination of wildlife
crossings and roadside fencing has been found to be helpful for some
species. Rimba’s Kenyir Wildlife Corridor Project lead researcher
Gopalasamy Reuben Clements, 32, says that in Malaysia, the Wildlife and
National Parks Department (Perhilitan) had previously tried to funnel
animals underneath viaducts through the construction of electric fences.
But
what works for wildlife crossings in other countries might not be
appropriate for Malaysia. One consideration is a difference in local
fauna. Elephants, for example, are known to have fixed migration routes;
they broke through the fencing.
Another important factor is
rampant illegal trade in wildlife. The country’s excellent
infrastructure and road networks, many of which bypass forest reserves,
not only open up access to wildlife poachers but offer convenient routes
for a speedy onward journey.
“So far, NGOs have been
recommending the building of viaducts but the poaching element hasn’t
been looked at,” Clements points out. The conservation biologist hopes
his study will determine whether animals at such wildlife crossings
might in fact, be more vulnerable to poachers.
The Kenyir
Wildlife Corridor Project is part of his PhD research with James Cook
University in Queensland, Australia. A Singaporean and Master’s graduate
from the National University of Singapore, Clements is also a research
associate with Universiti Malaya and previously worked at World Wide
Fund For Nature Malaysia on tiger and rhinoceros conservation projects.
In total, Clements and his team have installed 80 camera traps – 40
within forest reserves on either side of the highway, and the rest, in
and around the viaducts. They have covered 140sqkm of jungle, trekking
some 8km a day and roughing it out in the jungle, to look for signs of
wildlife and rotate cameras around the study grid to get a more
representative data.
Covering the entire area took them three
months, and they still have two more rounds of sampling to go before
it’s time to analyse the data. Nevertheless, the team has already been
able to glean some insights.
For example, they noticed one
particular tiger, recognisable by its stripes, was captured by cameras
located both north and south of the highway, but not at ones placed near
or under any of the viaducts.
“That shows it didn’t use the
viaduct. So for large mammals, these viaducts may not be so useful. But
as you can see, you have tapirs and other animals to consider, too. And
we don’t know whether the tiger will use the viaduct in the period
between now and the end of the study, so it’s just preliminary.”
Part
of the project’s mission is to identify potential access routes for
encroachment. This they found – near, under and along the viaduct access
road. They also found old camps in sheltered areas underneath the
viaducts, and cameras have captured images of people carrying fishing
rods. Such evidence of human presence is not seen at three of the newer
viaducts. Clements hypothesises that these are probably too remote.
The
study should reveal if wildlife are actually utilising the structures
and if so, which ones. But what do we do if the eco-viaducts prove to be
less effective than hoped? That, according to Clements, does not mean
the structures lose their usefulness. It might call for a tweak in
strategies – such as more wildlife patrols – to increase their
effectiveness.
By seeing how other factors determine the
effectiveness of eco-viaducts, future crossings can be planned
accordingly. Potential factors, says Clements, could be the distance
between the viaducts and human settlements, the quality of forests on
the other side of the road barrier, and physical features such as
reduced vegetation under the viaduct or reduced food resources due to
the presence of large adjacent water bodies.
Adoption programme
The
Rimba project is a mammoth undertaking requiring expensive technology
(the cameras, password-protected and possessing inbuilt lens, cost
RM1,500 each) and manpower (to conduct surveys and handle the cameras).
Clements has 80 camera traps in action right now but needs 150. With
more cameras, his team can do more accurate population estimates.
So
far, funds have come from grant disbursing organisations, including the
two universities Clements is attached with, and private donors. These
are enough to pay for the 80 cameras and five field assistants.
Rimba
also needs funds for 10 satellite collars for a project on the
management and ecology of Malaysian elephants, to be led by Ahimsa
Campos-Arceiz, an assistant professor with the University of Nottingham
(Malaysia campus). At RM13,000 each, the collars will show the movement
patterns of each animal, thus providing insight into how they cross
roads and use viaducts.
Companies, organisations, societies,
schools and individuals can support the work of Rimba by adopting a
camera, satellite collar or ranger.
> Camera trap
(RM1,500) – You will get a certificate, the opportunity to personally
place your camera trap in the forest, and get e-mail updates of captured
images every three months.
> Satellite collar
(RM13,000) – You will get updates of the collared animal every three
months, a half-yearly progress report and a three day-two night stay at
Rimba Field House.
> Ranger (RM18,000) – You will get a
certificate, an opportunity to place three camera traps in the forest,
receive e-mail updates on these traps every three months as well as a
half-yearly progress report, and a three day-two night stay at Rimba
Field House plus an opportunity to accompany the ranger on field
surveys.
Clements believes that creating a bridge between
researchers and the public as well as providing people with
opportunities to get involved in conservation projects can make a
difference. Research is important – it helps indirectly by knowledge
creation, and deters illegal poachers by the mere presence of
researchers in the forest. On that note, it is a cause worth supporting.
Source: myrimba.org