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  BBC 23 Jul 07
SE Asia faces 'catastrophic' extinction rate
By Alex Kirby BBC News Online environment correspondent

National Geographic 23 Jul 03
Singapore Extinctions Spell Doom For Asia?
John Pickrell

New Scientist 23 Jul 03
Biodiversity wipeout facing South East Asia

The Straits Times 24 Jul 03
Singapore has lost half its animal species: study
By Chang Ai-Lien

SINGAPORE has lost about half its animal species in the last 200 years, and the rest of the region is likely to follow suit, according to a landmark study here.

THE LIVING DEAD: Take a good look at the banded leaf monkey (above left) and cream-coloured giant squirrel if you see them in the wild, for some day they will be gone.

Both mammals are found only in Singapore, but their populations have shrunk so much that they are all but certain to become extinct.

A study by Singapore and Australia researchers predicts the loss of up to 42 per cent of animal populations in South-east Asia by the end of this century. Based on detailed documentation of the state of mammals, birds, fish and butterflies on the island, it found that at least 881 of 3,196 recorded species, or 28 per cent, had vanished forever.

However, taking into account the probable number of animals here before detailed records were made in the late 1800s, it predicted that this figure was actually higher - about half of Singapore's animals.

The study, done by researchers from the National University of Singapore (NUS) and Australia's Northern Territory University, is being published today in the prestigious science journal Nature, an international weekly which is read by researchers and scientists. It is one of a handful of such studies based on data gathered over such a long period.

By looking at the extensive habitat loss in Singapore and the current rate at which forests in the region are being felled, it predicted the loss of up to 42 per cent of animal populations in South-east Asia by the end of this century.

At least half will be species unique to this region.

'Clearly, large-scale conservation efforts need to be implemented if these rates of extinction are to be abated,' it said.

It added that in Singapore, since the British first established a presence here in the early 1800s, more than 95 per cent of the estimated 540 sq km of original vegetation has been cleared.

Now, nature reserves, which make up only 0.25 per cent of Singapore's land area, are home to more than half of the native animals here. Rapid, large-scale habitat destruction for agriculture and urban development were the main culprits behind the mass extinctions.

But over-hunting and fishing, and the heavy shelling of nature reserves during World War II, also played a role.

Some of the animals most threatened with extinction are two mammals found only in Singapore - the cream- coloured giant squirrel and banded leaf monkey, said Associate Professor Peter Ng of the NUS department of biological sciences, one of the authors of the study.

Sadly, they are almost certain to become extinct because their populations have shrunk to levels too small for them to be sustainable in the long run.

'These are effectively the living dead,' said Prof Ng, who is also director of the Raffles Museum of Biodiversity Research.

The prospects for Singapore's surviving animals look bleak, said the paper, pointing out that the 77 per cent of the species are under threat, and most of them reside in our nature reserves.

But all is not lost.

Said NUS Associate Professor Navjot S. Sodhi, a bird expert and co-author of the paper: 'Hopefully, South-east Asia can take some lessons from what has happened in Singapore, and do something to better protect its animals.'

He added that without Singapore's nature reserves, the results here would have been even bleaker.

Nee Soon Reserve, for example, is home to one-quarter of the remaining freshwater crab and fish here.

Said Prof Ng: 'It's imperative to hang on to all our protected areas. 'We can't change history, but we can try to hang on to what we have now.'

National Geographic 23 Jul 03
Singapore Extinctions Spell Doom For Asia?
John Pickrell in England for National Geographic News

Singapore has lost up to 73 percent of its plants and animals over the last two centuries, new data reveals.

According to one of the most robust studies of tropical extinctions yet attempted, more than one- fifth of Southeast Asia's total species could follow suit by the end of the century, if land degradation continues unabated. "In a worst-case scenario Singapore is a microcosm of what may happen in Southeast Asia as urban pockets increasingly expand," warned ecologist Barry Brook of the Northern Territory University in Darwin, Australia.

To further conservationists' woes, prospects for the remaining species are bleak.

World Conservation Union (IUCN) figures estimate that 77 percent of the island's remaining butterflies, fish, birds, mammals, and other species are threatened.

Deforestation for agriculture, rapid urban development, over-hunting, and even the shelling of nature reserves during World War II are all to blame, says a letter detailing the findings in the 24 July edition of the journal Nature.

Colonial Rule

Tropical forests harbor the majority of terrestrial life on earth, yet they are being destroyed or degraded at unprecedented rates by fragmentation, exploitation, and the introduction of non-native species.

Though extinction rates are well documented in temperate regions, home to most developed nations, tropical data is rarer. Most reports are anecdotal or based on loose predictions of how many species can remain in shrinking forest patches.

To fill that knowledge gap, Brook along with biologists Navjot Sodhi and Peter Ng of the National University of Singapore's Raffles Museum of Biodiversity decided to study Singapore: a perfect example of urban development, blessed with detailed historical lists of species recorded by British and Singaporean naturalists.

The British commandeered the island in 1819 as an oriental colonial outpost. Previously the island was home to no more than a few small fishing settlements.

"To have data on species going back two centuries for tropical forest is very unusual," commented ecologist Daniel Simberloff at the University of Tennessee in Knoxville. Most tropical regions are lucky to have species lists going back 30 years, he said.

To estimate extinctions, Brooks' team used both modern species lists and historical ones going back to the 1870s for plants, crustaceans, butterflies, fish, amphibians, reptiles, birds, mammals, and other groups.

As less data was available for earlier colonial times, the researchers also inferred the presence of species found on checklists for very similar habitats in Malaysia's adjacent peninsula.

Huge Losses of Species

The analysis that species that may have been lost include as many as 4,866 plants, 627 butterflies, 234 fish, 111 reptiles, and 91 mammals. Since 1923 alone, 61 of the 91 known forest-bird species have died out. As much as 73 percent of the island's original biota (flora and fauna) has been extirpated.

Even measuring recorded losses for Singapore alone, and not adding the data from Malaysian lists, a minimum of 28 percent of species have been lost in the last 183 years.

One well-documented loss is the tiger, the last of which was shot in the 1930s.

Other species are "living dead"—reduced to impossibly small numbers and very unlikely to bounce back. The white-bellied woodpecker, banded leaf monkey, cream-colored giant squirrel, and many tree species are all represented by just a handful of individuals.

More than 95 percent of Singapore's original 540 square kilometers (208 square miles) of tropical forest have been felled: first for agricultural crops such as black pepper, and later for urban development in the burgeoning city state.

Less than one tenth of the remaining 24 square kilometers (9 square miles) of forest is old-growth vegetation and much of it has been re-established on abandoned farmland. In addition, 50 percent of remaining species are squeezed into tiny reserves covering no more than 1,547 hectares (3,800 acres).

One quarter of the remaining freshwater fish species are found in just a single five-hectare (12-acre) patch of one reserve.

The figures reported for Singapore have wider implications, said Brook. "In most respects a local extinction is like a global extinction," he said. When all the local populations of a species have been extirpated, it becomes globally extinct.

The scientists used the data to estimate how Southeast Asia's entire tropical diversity might fare if current rates of deforestation continue. Satellite images show that around 0.7 percent of the forests are currently lost annually.

Extrapolating this loss into the future they predict that 74 percent of the region's original vegetation will disappear by the turn of the next century. Almost half the forests found prior to human alteration of the environment have already gone, said Brook. Following the Singaporean example, the researchers estimate that up to 42 percent of local plant and animal populations will have died out by the year 2100. "More than half of those will be global species extinctions," said Brook. That's one fifth of Southeast Asian species.

"This is a very interesting and depressing analysis," commented the University of Tennessee's Simberloff, adding that the actual and inferred species losses for Singapore were almost certainly correct.

"There's certainly nothing outrageous about the extrapolations either," he said. It's plausible and worrying that Asia could lose so many species in the next century, he added. However, " we hope that measures will be taken to minimize extinctions by preserving habitats very rich in species." There are steps that can be taken to mitigate species losses even with such "horrendous" rates of deforestation, he said.

New Scientist 23 Jul 03
Biodiversity wipeout facing South East Asia

More than 40 per cent of the animal and plant species in South East Asia could be wiped out this century, with at least half representing global extinctions.

This dire prediction results from the first systematic study of species disappearance in Singapore, considered a "worst case scenario" for what could happen in the rest of the region.

"These predictions are grim - and they probably will unfold," says Barry Brook of the Northern Territory University, Darwin, Australia, who conducted the new research with colleagues at the Raffles Museum in Singapore.

"Any effective conservation would need a strong effort from governments to preserve large continuous areas of habitat, but, being a realist, I can't see that this will take place."

Unprecedented and expanding programmes of deforestation in the Philippines, Indonesia, Malaysia and neighbouring countries mean the future of the region is likely to be small islands of forest surrounded by a sea of agriculture and human occupied lands, says Brook.

Lee Tan, co-ordinator of the Asia-Pacific Unit of the Australian Conservation Foundation, agrees that large-scale attempts to protect biodiversity are unlikely: "There is a very strong push for urbanisation in South East Asia, and as a result there are very limited resources for conservation and environmental protection."

In microcosm Singapore represents a well-studied microcosm for events unfolding throughout South East Asia, Brook thinks.

Since 1819, land-clearing has destroyed more than 95 per cent of the original vegetation cover. The forests that remain today are protected.

But more than three quarters of Singapore's species are considered "threatened", according to World Conservation Union criteria. Some, such as the cream-coloured giant squirrel and the white-bellied woodpecker, have populations so small that they are almost guaranteed to go extinct.

The team's study of more than 30 published species checklists shows that Singapore has lost at least 28 per cent of its biodiversity in the past 183 years. Butterflies, fish, birds and mammals have been particularly affected.

But, based on surveys of species found in neighbouring Malaysia, they think habitat loss in Singapore could have wiped out many species before they were ever documented, and the true extinction figure could be as high as 73 per cent.

Mammals to crustaceans

Tropical forests are home to a greater biodiversity than anywhere else on the surface of the Earth. Extrapolating to the rest of South East Asia, where deforestation is predicted to reach 74 per cent by 2100, Brook thinks there will be an accompanying disappearance of between 13 and 42 per cent of plant and animal species in the region.

Some, such as butterflies, will vanish much more quickly than other, longer-lived species, such as trees that escape logging.

Thomas Brooks, at the Center for Applied Biodiversity Science in Washington DC, says the study is important because of the wide range of species considered, from mammals to crustaceans.

But he is more hopeful that something can be done: "Fortunately, the time-lag between habitat loss and species loss does give South-East Asia a window of opportunity to mobilise biodiversity conservation on the scale necessary to stem these extinctions."

Journal reference: Nature (vol 424, p 420)

BBC 23 Jul 07
SE Asia faces 'catastrophic' extinction rate
By Alex Kirby BBC News Online environment correspondent

The rate of extinction threatening to engulf south-east Asia this century could be a "catastrophic" 20%, scientists say.

They base their warning on the example of Singapore, where key habitats have shrunk by 95% since 1819. The scientists say it is the unprecedented rate of habitat loss that now threatens so many species.

South-east Asia is one of the Earth's most important biodiversity "hotspots". The scientists, from Singapore, Japan and Australia, report their findings in the journal Nature.

They found "substantial rates of documented and inferred extinctions, especially for forest species", with butterflies, fish, birds and mammals all affected.

The authors say: "Observed extinctions were generally fewer, but inferred losses often higher, in vascular plants, phasmids (stick and leaf insects), decapods (crustaceans), amphibians and reptiles.

Global impact

"Forest reserves comprising only 0.25% of Singapore's area now harbour over 50% of the residual native biodiversity."

They think the rate at which habitats are disappearing is so great that south-east Asia will lose up to two-fifths of all its species over this century, at least half of them endemic species found nowhere else on Earth.

They used both historical and modern checklists of species occurring in Singapore to estimate how many had become extinct, in relation to large-scale habitat loss, since the British arrived in 1819.

Since then more than 95% of the estimated 540 square kilometres of original vegetation has been entirely cleared. Less than 10% of the remaining 24 sq km of forest is primary growth.

The authors also used checklists from nearby peninsular Malaysia to deduce the possible species composition of Singapore in 1819, compensating for probably incomplete extinction records.

The overall loss of biodiversity, they calculated, was at least 28% - 881 of 3,196 recorded species. Butterflies, freshwater fish, birds and mammals lost 34-43% of all species. About a quarter of all vascular plants, freshwater decapods and phasmids have disappeared.

On the slide

But there seem to have been comparatively fewer extinctions of amphibians and reptiles.

Total local extinction rates, the authors say, could be as high as 73%. They say their lists of surviving species include several long-lived ones whose populations are too small to survive in the long term, like the white-bellied woodpecker, the banded leaf monkey and the cream-coloured giant squirrel.

They say: "These 'living dead' taxa will almost certainly become extinct in the coming decades."

Forest birds have fared worse than open-habitat species: since 1923, 61 of the 91 known forest-dependent birds have disappeared.

The authors say rapid and large-scale habitat destruction was undoubtedly the predominant cause of Singapore's extinctions. But hunting may also have been important: Singapore's last tiger was shot in 1930.

They describe the prospects for its surviving species as "bleak", with 77% classified as threatened by IUCN-The World Conservation Union.

Quart in a pint pot

With the few remaining protected nature reserves occupying only 0.25% of the island's total land area, they worry at how much biodiversity is packed into so small a space.

On Singapore's lessons for south-east Asia, they note a projected overall deforestation rate of 74% for the region by 2100. They conclude: "We predict the overall loss of 13-42% of regional populations due to the effects of deforestation in south-east Asia by the end of the present century, at least half of which are likely to represent global species extinctions."

Caroline Pollock, of IUCN's Red List programme, told BBC News Online: "The projected loss for south-east Asia is very high, but it's not really a surprise.

"We're finding increasing numbers of species are being assessed as threatened, and we expect more and more species will go downhill."
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