Best of our wild blogs: 25 Dec 12

My new website!
Urban Forest: An Identification Guide to the Flora of Singapore and Southeast Asia
from Urban Forest

Purple Heron – Comfort Behaviour
from Bird Ecology Study Group

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Yangtze finless porpoise population declines

WWF 24 Dec 12;

Wuhan, China -- A total of 380 Yangtze finless porpoise have been visually identified during a survey expedition along the Yangtze River, marking a significant decline from a previous research in 2006, according to initial results.

"There is a notable downtrend in the population size of the finless porpoise based on our observation," said Wang Kexiong, deputy head of the research expedition and an associate researcher at the Chinese Academy of Sciences’ Institute of Hydrobiology (IHB).

Two survey ships docked at IHB's wharf in Wuhan of Hubei on Monday, concluding a 44-day and 3,400km round-trip voyage between the Chinese cities of Yichang and Shanghai.

Meanwhile, acoustic equipment identified 172 finless porpoise during the expedition.

Results of the expedition, including the population of the finless porpoise in the Yangtze River, are to be made available in about two months after sufficient analysis, said Wang.

"Compared with the 2006 survey, the distribution areas of finless porpoise remains roughly the same, with signs of scattering in some parts," said Wang.

There are fewer finless porpoise in the mainstream of the Yangtze while more discoveries have been made in wharf and port areas.

"That could be attributed to rich fish bait resources there. Busy shipping traffic in the mainstream, especially in port regions, poses a threat to the survival of finless porpoise," said Wang.

Shipping traffic in the mainstream of Yangtze River -- the lower reaches in particular – has increased considerably, with an average of 100 cargo ships per hour passing through. Rates were even higher in the Zhenjiang-Jiangyin section of the Yangtze, with an average of 105 cargo ships passing every half hour.

"Such shipping traffic volumes would become a potential threat to the finless porpoise who rely on their sonar system to survive," said Zhang Xinqiao, expedition team member and WWF finless porpoise programme officer.

The team encountered 9,643 cargo ships and 736 fishery ships during voyage, which ran from 11 November – 23 December 2012.
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Researchers found dense distributions of finless porpoise in waters that are not open to navigation, such as the Jiajiang River, and attribute this to less human disturbance.

Less optimistic was the discovery of illegal fishing practices in these areas, including traps that could affect finless porpoise. .

"Generally, the finless porpoise are scattered in the Yangtze mainstream, with a small group of them living in a comparatively narrow area. Such an isolation is not necessarily a positive thing for their reproduction," cautioned Wang.

The scattered distribution pattern could be the result of shipping traffic that made migration harder, projects that altered hydrological conditions in the middle and lower reaches and habit loss, said Wang.

The findings on the number of population and variation trend are to be finalized according to a model that takes validity of calculation, density of distribution, width of the river, sailing length and areas covered into consideration.

The results are to contribute to the drafting of Action Plan for the Yangtze Finless Porpoise Conservation by the Ministry of Agriculture and proposals concerning the conservation areas.

Led by China's Ministry of Agriculture and organized by the IHB, WWF and Wuhan Baiji Dolphin Conservation Fund, the expedition first set sail on 11 November and comes only six years after the Baiji dolphin - another rare cetacean and close relative of the finless porpoise - was declared functionally extinct.

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Best of our wild blogs: 24 Dec 12

Latest Green Jobs in Singapore [17 - 23 Dec 2012]
from Green Business Times

Cotton pygmy-geese - Preening and stretching
from Bird Ecology Study Group

Asian Koel
from Monday Morgue

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Illegal animal trade active on Singapore local sites

Study finds 23 websites offer banned wildlife, parts
Feng Zengkun Straits Times 24 Dec 12;

A "PET" tiger, a grey tundra wolf and exotic parrots were some of the animals that online wildlife traders tried to sell to Singaporeans last year.

A new research project by the National University of Singapore (NUS) has thrown a spotlight on dark corners of the country's online animal marketplace.

It found that 23 local websites carried more than 1,300 new advertisements selling trade-restricted animals and their parts - many of them exotic and possibly illegal - in the second half of last year.

The price-tags on the animals added up to $680,000, and this excluded those ads which featured no prices.

In all, more than 50 new advertisements were posted each week during the 28-week study, and the traders could have netted almost $1 million, the project estimated.

The research, likely the first of its kind here, involved monitoring popular local pet and classified ad sites such as Pet.sg and eBay between September last year and January.

The project also included search results of ads posted on the sites in July and August last year.

It found that three-quarters of the ads hawked live animals as pets - either legal or illegal ones. Dead animals and parts such as ivory, horns, skin and fur made up the remainder.

Worryingly, one in three of these creatures and parts was banned here by the Agri-Food and Veterinary Authority (AVA).

Some animals were likely to have been smuggled in. For example, eight advertised species of non-native birds were not imported here between 2002 and last year, according to records.

Species included the vulnerable red-necked Amazon parrot and military macaw.

The report acknowledged that some of the ads were probably scams, such as those hawking pet tigers and wolves.

Also, the ads may not have translated to actual sales.

"But the persistence of the new ads and the views they get suggest there is interest in Singapore in paying for the exotic animals," added the report.

The study also captured only ads in English, so the total number of online animal ads here is likely to be much higher.

Wildlife activists said such ads were "mushrooming" in every part of the world.

Mr Louis Ng, executive director of the Animal Concerns Research and Education Society here, said regular sting operations to nab online traders would reduce the virtual traffic. The group recreated the NUS project between June and August this year after conducting several stings with the help of the AVA, and found fewer ads.

When asked, the AVA said it monitors retail outlets and online sources of sales of illegal wildlife and their parts and products. Between January and last month, it investigated eight cases related to online sales. Of these, three were prosecuted in court.

"AVA also works with online sites such as forums, classified ad pages and auction sites to share information on the laws prohibiting the possession and sale of illegal wildlife in Singapore," a spokesman said.

It is an offence for people to import, export and re-export protected wildlife, including parts and products, without an AVA permit. It is also an offence to possess, sell or advertise wildlife which has been illegally imported or bought. Offenders can be fined up to $50,000 per animal, up to $500,000 in total, and/or jailed for up to two years.

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Malaysia: East-West Highway easy game for poachers

Nuradilla Noorazam New Straits Times 24 Dec 12;

GRAVE CONCERN: 100 points along East-West Highway for illegal hunters to enter Belum, Temenggor forests

KUALA LUMPUR: EASY access into the Royal Belum state park and Temenggor forest reserve along the East-West Highway has allowed poachers to make a killing on the country's rich wildlife.

Connecting the state of Perak and Kelantan, the highway stretches up to 124km between Grik and Jeli.

According to wildlife conservationists, there are more than 100 access points along the road for poachers to enter the forests.

As a consequence, seizures of wild animal parts in the northern part of the peninsula and its borders had raised concerns about poaching activities in Belum and Temenggor.

Almost four times the size of Singapore, the forests are home to 274 species of birds, 100 species of mammals and 69 species of reptiles. It also contains 3,000 species of flowering plants.

Statistics from the international wildlife trade monitoring network Traffic Southeast Asia (TSEA) showed that 122,880 individuals had been caught nationwide for possessing endangered animals between 2001 and last year.

The largest seizure was in 2010, when National Parks and Wildlife Department (Perhilitan) officers confiscated over 26,000 pieces of python gall bladders, 35,000 pieces of python skin and three pangolins in Kedah and Perak.

TSEA senior programme officer Kanitha Krishnasamy said lucrative animals in the wildlife trade such as Malayan tigers, honey bears, Asian elephants, pangolins and leopards could also be found in those forests.

"Since 2008, our information revealed that at least 400 wild animals had been poached and traded illegally in these two landscapes, including tigers, serows, gaurs, pangolins, sun bears, birds and deer."

Members of TSEA, together with the World Wide Fund for Nature-Malaysia (WWF-Malaysia), had discovered and removed 150 snares from the vast forests.

In April 2009, a five-year-old male tiger was caught in a snare set by poachers near the highway and released by Perhilitan officers.

The tiger was found with tears in its eyes and suffering severe injuries. The cable wire from the snare had cut into its flesh when the animal struggled to escape.

It was then sent to Malacca Zoo for treatment but died two weeks later, much to the disappointment of its rescuers.

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Tree that weeps dragons blood among new discoveries

A tree with “dragons blood” running beneath its bark, a rare mountain top snowdrop and a critically-endangered orchid are among more than 60 new species discovered by botanists in the past year.

Richard Gray The Telegraph 23 Dec 12;

Scientists at the Royal Botanic Gardens in Kew made the discoveries during a series of expeditions to some of the remotest corners of the world.

Yet despite only recently being catalogued, many of the new plants could disappear all together due to threats to their habitats.

One tree, found growing on top of a ridge among knife-like limestone blades of rock in Thailand, oozes a dark red sap - rumoured in local folklore to be “dragons blood” and drunk as a medicinal tonic - is already considered threatened.

Dr Paul Wilkin, a team leader at the herbarium at Kew who identified the tree as a new species, said the limestone outcrops where it grows are quarried for building material while it is also heavily collected by locals who consider it to be lucky.

With tough leathery leaves and a dark red sap that oozes from the bark when damaged, it is known as the Red Dragon Tree, or Chan Daeng in Thai. The botanists have now given it the scientific name Dracaena jayniana.

Dr Wilkin said he found the tree after being led up a trecherous ridge of limestone near Chiang Mai by local scientists and believes he has found a second new species growing in similar locations.

He said: “The tops of these karsts are covered in weird vegetation. The limestone mountains are very steep sided and have knifelike ridges, so you can’t have any farming there, so you get these quite remarkable plants growing there.

“There is a real overlooked diversity of plants in Thailand. The Red Dragon Tree is related to other species that are also used for medicinal purposes. They are used for everything from curing wounds, fractures, piles and stomach ulcers.

“This one seems to be used as a general pick me up tonic, but what the exact medicinal function is will need some more research.”

Scientists at Kew also discovered a new snowdrop, which they named Galanthus panjutinii, or Panjutin’s snowdrop after a famous climber and naturalist in the Caucasus Mountains called Platon Sergeevich Panjutin.

It was found on just one moutain ridge in Russia and joins 30 other species of snowdrop previously known in the world. The scientists, however, fear the new flower could already be under threat due to the small area it is found in.

They are refusing to reveal the exact location for fear that bulb hunters will raid the mountain side in search of the new species to sell to gardeners.

A new orchid, named Ornithocheirus cacharensis, was also discovered in the Cachar region of Assam, in northern India, a region better known for its tea. There are thought to be just ten of these red and purple plants in an area that measures less than three square miles.

Botanists also discovered 15 new species of palm tree. One example Indonesia, called Adonidia maturbongsii, has huge bat-like leaves while another from Papua New Guinea, called Heterospathe barfodii, produces clusters of purple flowers.

They also found 14 new species of Indigofera, a type of plant that was widely used to produce indigo dyes.

One expedition to the South Atlantic Island of St Helena, a UK Overseas Territory, discovered a new species of grass, which they named Eragrostis episocpulus, or wavy hair grass.

David Simpson, acting head keeper of the herbarium at Royal Botanic Gardens, Kew, said: “St Helena is a small island, so you might have thought that almost everything should have been found there, but the fact this has only just been discovered makes it more interesting.

“A lot of species on that island are not found anywhere else in the world and that makes them very special.”

Many of the new species discovered by Kew’s scientists, however, are already under threat.

The scientists also discovered some new species had already been collected in the past but had been misidentified before being locked in drawers in Kew’s vast herbarium.

They found 11 new species of Orania, a type of palm tree, hidden in the archives.

Dr Simpson added: “Techniques like DNA sequencing is helping us to work out relationships with other plants and it is a tool we have not had available in the past.

“In general we think there are something like 70,000 news species still out there waiting to be discovered.

"You often find these things more by chance than by anything else – if you happen to be in the right habitat when a particular plant is flowering.”

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Best of our wild blogs: 23 Dec 12

Life History of the Banded Swallowtail
from Butterflies of Singapore

Straw-headed Bulbul – contact calls?
from Bird Ecology Study Group

Is this really Singapore? Pasir Ris shoreline covered with rubbish
from Lazy Lizard's Tales

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ACRES seeks public debate on dolphins

Channel NewsAsia 22 Dec 12;

SINGAPORE: Animal welfare group ACRES wants a debate on the dolphins which are at the heart of the controversy surrounding Resorts World Sentosa's Marine Life Park.

ACRES said it has invited Resorts World Sentosa (RWS) to a public debate on January 19 next year.

The group said the debate will provide the public with facts so that they will be able to hear both sides of the story and make an informed decision about the dolphins.

The Marine Life Park, which opened earlier this month, is the world's largest oceanarium.

It is home to more than 100,000 marine animals, including 24 bottlenose dolphins which were caught from the wild.

ACRES said it has also sent an email to Resorts World Sentosa to clarify statements that RWS has made on the dolphins, urging RWS to respond to the concerns that ACRES and members of the public have raised.

Among the concerns raised are public safety issues during the proposed dolphin contact sessions, as well as animal welfare and conservation issues.

ACRES' chief executive, Louis Ng, said RWS has turned down his requests for meetings for more than a year, and he hopes that RWS will accept his latest invitation for a "positive discussion".

Twenty-seven dolphins were captured from the Solomon Islands between 2008 and 2009, and sent to Malaysia and the Philippines for training while the Marine Life Park was under construction.

One of the dolphins died en route to Singapore in November, while two others died in 2010 in Malaysia from bacterial infections.

Singapore's Marine Life Park has said that its acquisition of the Indo-Pacific bottlenose dolphins followed international requirements.

When asked if it would agree to the public debate, RWS reiterated what it said in a letter published in the TODAY newspaper on Wednesday.

RWS said the "acquisition and care of our dolphins have and will continue to meet and, wherever possible, surpass international guidelines and regulations".

It added that this commitment is not generated from a legal obligation, it is because "we want to do the right thing for our animals".

It said RWS "will not compromise the well being of our marine animals", and that the dolphins, now in their required quarantine period, are acclimating well to their new home at Marine Life Park.

It urged ACRES to "contribute constructively to marine conservation while appreciating that it requires many strategies, experts and resources to turn the tide for the future of marine life".

- CNA/al/xq

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Singapore Palm Oil Firm Ordered To Stop Clearing Indonesian Forests

Jakarta Globe 22 Dec 12;

The Roundtable on Sustainable Palm Oil ordered Singapore-based First Resources palm oil company to stop clearing forests in East Kalimantan until conflicts with the local Dayak community are resolved, an environmental agency said on Friday.

First Resources, an RSPO member, began clearing forests in East Kalimantan without obtaining the necessary consent of the local Dayak Benuaq community, the London-based Environmental Investigation Agency alleged in a complaint filed against the company.

The RSPO backed the complaint, stating that the nonprofit heard evidence that First Resources’ violations were not a “one-off” instance and may be “systemic in nature” due to similar complaints lodged in West Kalimantan.

First Resources was ordered to stop all disputed operations in the Kutai district until the company can work with EIA to reach an “amicable solution.” The nonprofit cannot legally force the company to stop operations, but it can suspend First Resources’ RSPO membership.

EIA heralded the decision, but promised continued pressure on First Resources.

“The fight is by no means over and EIA, the community and other NGOs will be watching First Resources’ every move,” EIA Forests Campaigner Tom Johnson said. “The company must stop behaving like a gang of thugs.”

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Malaysia: Why the water keeps rising

New Straits Times 23 Dec 12

MONSOON TROUBLES: The Drainage and Irrigation Department has been tasked with implementing structural and non-structural flood mitigation measures since 1971. Yet, the frequency and severity of floods in Malaysia do not seem to subside. Director-general Datuk Ahmad Husaini Sulaiman tells Tan Choe Choe why flooding can never be eliminated and his plans to develop a nationwide flood-risk map

Question: Billions of ringgit have been spent on flood mitigation and risk-management efforts for years, yet there doesn't seem to be any reduction in the severity of floods. Why?

Answer: The intensity of rainfall that we have here is high -- 3,500mm annually. We have plenty of rain throughout the year, especially during the monsoon season. You must accept that most structural measures we've implemented have solved many problems. There may still be flooding, but not the kind we used to have.

Question: But many new areas are getting flooded.

Answer: Yes. We're looking into the reasons. But when building flood mitigation projects and structural measures, we design them to a certain flood defence level.

You can't tell people that it could cope with the biggest rainfall that would ever happen -- that will take huge amounts of money and land. There can't be zero flooding but it will be minimised. In our case, we design (our projects) for a rainfall of 100-year return period.

(A return period is an estimate of how long it will be between rainfall events of a given magnitude. If the return period for a two-hour rainfall of 101mm in Tebrau is 10 years, then a 101mm rainfall over two hours will occur in Tebrau once every 10 years.)

If the rainfall is too intense, then the system that we've built earlier for the 100-year return period won't be able to cope with it. Billions have been spent, yes, but we must also understand that structural measures are expensive.

And you must understand when water flows into the river, it flows from one end (upstream) to the sea. It is a long stretch. The total solution would be to address the whole stretch. But that's going to be very expensive. So, we strategise and decide where best to put the structural measures along the river.

There are two types of floods: river and flash floods. River flooding occurs when the river spills its banks, flooding the surrounding lowlands. Flash floods are short-period floods that occur because of the concentration of heavy rainfall in an area. If the area's internal drainage system is not good, not properly maintained, then you get flash floods.

Question: So, it's mostly a drainage issue for flash floods?

Answer: Yes, you can't help it when you have these problems. The important thing is to maintain the system for better water flow. If not, you get drains that are choked with rubbish and when rain falls, water won't be able to flow into the river. That creates flash floods. The other reason is the increasing intensity of rain. It's so intense that the local drainage system cannot cope with the amount of water falling in that short period of time.

Question: You've taken over the DID from your predecessor for more than four years now. What has been the most challenging problem to you?

Answer: It's our vision to see that the country achieves a better standard of living in terms of what we say the "Happiness Index". We hope that flooding will not get too serious so people will be happy in Malaysia that we've got a good system that can cope with the rain.

Question: Then I must measure badly on that "Happiness Index" because whenever it rains, it's 'Sigh, can't go home again'.

Answer: In Kuala Lumpur, we're talking about flash floods, but river flooding is almost nil because of the Stormwater Management and Road Tunnel (Smart) that we've built. A lot of rainwater that flows into Sungai Klang has been diverted, bypassing the city centre entirely.

Question: In terms of flash floods, is there any mitigation effort that you're looking at?

Answer: I can't pinpoint any agency which should be looking at that. We are looking at the bigger system. The internal drainage will have to be the local authorities.

Question: Doesn't the DID advise them?

Answer: Yes, we do talk to see what the best solutions are for improving internal drainage.

Question: But you can't compel them to follow through with your suggestions?

Answer: Not really. We advise. If a developer is developing a piece of land, they have to submit the drainage plan to us for our comments. Then, we will advise the local authorities on whether the system is acceptable or not.

Question: If you find that the drainage plan they submitted is not acceptable, do you have the authority to halt the project until they revise the plan?

Answer: No, we are only giving our comments. It is up to the local authorities to listen to us and advise the developer to make the necessary changes.

Question: In that context, the DID's power seems to be limited. It's pretty much up to the local authorities?

Answer: Yes.

Question: Do you feel frustrated by this?

Anwer: We see a lot of new developments and Kajang is one example where plenty of new developments have been taking place, and floods there have been shocking recently. Answer: What can I say? We've given our comments, our advice on how the system should be built. It is up to the developers and the local authorities to agree on how best to build on what has been approved.

Question: Are most drainage plans submitted by the developers up on a par, or do you often find something lacking in their plans?

Answer: It depends. Some are good, some are not. We don't have figures to show how many are good and how many are not.

Question: The Integrated Flood Management System (IFM) -- how does it really work? Does it only cover river flooding or does it also address flash floods?

Answer: Both. We look at the structural and non-structural measures. We look at maximising the positive effects of the water cycle, to integrate land and water management and to adopt the best strategies with a participatory approach.

It's not easy to understand or implement some of these elements. Like getting people to work with us, there are those who are willing to listen and those who are not. They assume that any problem should be solved by the government and so it's not their responsibility.

Question: DID is the lead agency in IFM and is responsible for solving river and flash floods. But you indicated earlier that the DID's hands are tied in terms of flash floods as it's more an internal drainage issue at the hands of local authorities. How can the IFM address flash floods then?

Answer:It's an integrated system, so they also have to come and play a part. If the local authorities need advice from us, we'll sit together and discuss what is best to be done.

Question: When you propose measures, do they listen?

Answer: Yeah, they listen, they have to listen. Otherwise who else are they going to depend on?

Question: Yet, you indicated earlier that...

Answer: Yeah, of course, but I can't say for sure the reasons sometimes they don't listen to us. I don't know. But usually, they will listen.

Question: Yet the severity of flash floods, in Kuala Lumpur for example, hasn't gone down. Why?

Answer: When it rains, there will be standing water on the road. Then people slow down and that creates a jam that will drag about 3km to 4km down the road.

But that's not a flash flood, which gets to a certain height or even goes into your house for one or two hours before it recedes.

Yes, maybe in KL, in the Gombak catchment area, there are one or two cases where we have that problem because of intense rainfall. But usually, it is still manageable.

You're right, there are floods, but I don't think it's that serious. Remember in 2006, when Smart wasn't completed yet and Sungai Klang overflowed its banks? The whole city was like a sea. Now, you don't see that any more.

Question: What is the biggest challenge in implementing the IFM?

Answer: Updating of flood hazard maps. When there's a flood, we need to update our data, to see the reason of flooding. We need to do this frequently and there have been intense rainfall and changes in land use as development has been quite rapid, especially in the Klang Valley.

There are three types of maps: flood map, hazard map and flood-risk map. The flood map tells you areas with historic flooding. The hazard map is generated using simulations to show all areas that would potentially be flooded with certain magnitudes of rainfall.

The flood-risk map has the two elements, with a third component. It tells you where to head in times of floods, and what to do. It will also tell you where the relief centres are.

We have the flood and hazard maps now, but we are still building our flood-risk maps.

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Best of our wild blogs: 22 Dec 12

Antsurrection
from The annotated budak

Pied Imperial-pigeon feeding on Rhopaloblaste ceramica fruits
from Bird Ecology Study Group

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Bat gene clue to beating bugs

Grace Chua Straits Times 22 Dec 12;

BATS harbour viruses that can infect and even kill humans and animals, like Sars, Hendra and Nipah. Yet infected bats rarely fall sick.

Now, a Singapore-led team of international scientists has worked out a possible reason and believes it could help stop viruses leaping to humans and other animals.

The findings could even help to treat viral illnesses.

The key lies in bat genes. In July, the researchers started sequencing the genomes - the whole set of genes - of two very different bats.

One was a large fruit bat, a member of a group called megachiroptera. The other was a small insect-eating one belonging to a group called microchiroptera.

As these species are so different, any genes they share come from the last common ancestor of both bats.

Professor Wang Linfa, director of the Duke-NUS graduate medical school's Emerging Infectious Diseases Programme, led the team, which studied which genes had been selected most successfully during evolution.

Bats are the only flying mammals, and flight takes a great deal of their energy. The higher metabolic rates that supply this energy also produce toxic by-products that damage DNA. But bats seem to have evolved ways to protect their cells against this damage, Prof Wang explained. These DNA-repair genes also play a role in immune pathways, so researchers think they may help to protect bats.

A group of genes involved in inflammation was completely absent in bats. Inflammation is the body's response to an invader, such as a virus, resulting in viral illness.

Said Prof Wang: "We don't want to jump to conclusions that this means bats have less inflammation during viral infection. It's only one discovery and we have to do more to functionally prove that it contributes to less pathology in viral infection in bats."

But simply responding less to viruses could be part of why bats do not fall ill, he said.

Prof Wang led an international team spanning Singapore, China, Denmark and the US. Its work, published yesterday in the journal Science, may one day help prevent transmission of these viruses. It may point to better ways to treat viral diseases by using gene therapy, for example, to control inflammation, Prof Wang said.

National University of Singapore evolutionary biologist Rudolf Meier, who was not involved in the study, said some changes in the bat genes were present in other species, including humans, but without the protective DNA-repair or immune-system effects. He said the results were not wrong, but not conclusive.

Bats' viral immunity linked to their ability to fly
Heng Wei Xiang Today Online 22 Dec 12;

SINGAPORE - The evolution of flight in bats may has contributed to the development of a highly effective immune system, allowing these mammals to harbour some of the world's deadliest viruses such as Ebola and SARS.

This is according to researchers at Duke-NUS Graduate Medical School, who published their findings in the international journal Science. Less than 10 per cent of research papers submitted to the journal are published.

Professor Wang Lin Fa, an infectious disease expert who led the study, hopes the findings could provide new research directions, especially in the treatment, prevention and control of emerging infectious diseases that affect both humans and livestock.

The researchers studied two bat species, the black flying fox and the mouse-eared bat. While a high metabolism is a prerequisite for bats to be able to fly, such metabolic rates also increase the amount of free radicals present within cells in the bat's body. Excessive amounts of free radicals lead to DNA damage, contributing to major bodily disorders. Researchers found gene variants in these bat species, enabling them to minimise and repair DNA damage.

However, the same gene variants also boost bats' immune systems, allowing them to resist many viruses such as Nipah, Ebola and SARS, which typically cause severe illness in other species, humans included.

"Our findings highlight the potential of using bats as a model system to study infection control, tumour biology, and the mechanisms of ageing," said Prof Wang, who was appointed Director of the Program in Emerging Infectious Diseases at Duke-NUS in July this year.

Long-lived bats offer clues on diseases, aging
Tan Ee Lyn Reuters Yahoo News 21 Dec 12;

HONG KONG (Reuters) - The bat, a reservoir for viruses like Ebola, SARS and Nipah, has for decades stumped scientists trying to figure out how it is immune to many deadly bugs but a recent study into its genes may finally shed some light, scientists said on Friday.

Studying the DNA of two distant bat species, the scientists discovered how genes dealing with the bats' immune system had undergone the most rapid change.

This may explain why they are relatively free of disease and live exceptionally long lives compared with other mammals of similar size, such as the rat, said Professor Lin-Fa Wang, an infectious disease expert at the Duke-NUS Graduate Medical School in Singapore who led the multi-centre study.

"We are not saying bats never get sick or never get infections. What we are saying is they handle infections a lot better," Wang said in a telephone interview.

What was missing from both species of bats was a gene segment known to trigger extreme, and potentially fatal, immune reactions to infections, called the cytokine storm.

Cytokine storms end up killing not only offending viruses in the body, but the host's own cells and tissues too.

"Viruses rarely kill the host. The killing comes from the host's immune response. So it looks like what bats are doing is depress the inflammation (cytokine storm). If we can learn that, we can design drugs to minimize the inflammation damage and control viral infection," Wang said.

The study, which saw the participation of researchers from China, Denmark, Australia and the United States, was published on Friday in the journal Science.

Compared with other mammals of similar size, bats live a long time, with lifespans of between 20 and 40 years. Rats live between 2 and 3 years, on average.

IMMUNE GENES LINKED TO FLIGHT

Interestingly, Wang and his colleagues found that the highly evolved genes that give bats their superior immune system also enable them to fly.

Out of more than 5,000 types of mammals on the planet, bats are the only one capable of sustained flight and some species can fly more than 1,000 km in a single night.

Such intense physical exertion is known to produce toxic "free radicals" that cause tissue damage and it is these same genes that give the bat the ability to repair itself, Wang said.

"What we found was the genes that evolved fastest were genes involved in repairing DNA damage. That makes sense ... because when you fly, metabolism goes up and it generates free radicals that are toxic to cells," Wang said.

"Because bats fly, they (would have had) to evolve and adapt ... to get genes that can repair DNA damage."

Wang said we have much to learn from the bat, which has evolved to avoid disease and live exceptionally long lives.

"Cancer, ageing and infectious disease, these are the three major areas of concern for people," he said.

"We have studied rats for 150 years to understand how to do better in these three areas. Now we have a system, the bat, that has done very well in evolution. We can learn from the bat. With modern techniques, we can design new drugs to slow down the ageing process, treat cancer, fight infections."

(Editing by Robert Birsel)

Bats' flight linked to immunity
Duke NUS Science Alert 7 Jan 13;

An international team led by an infectious disease expert, Professor Lin-Fa Wang, at the Duke-NUS Graduate Medical School (Duke-NUS) in Singapore has found that the evolution of flight in bats may have contributed to the development of a highly effective immune system, allowing bats to harbour some of the world’s deadliest viruses such as Ebola and SARS.

In their study, published in the prestigious international journal Science, Professor Wang and colleagues used a state-of-the-art whole-genome sequencing technique to analyse the genomes of two distantly-related bat species, the fruit bat Pteropus alecto (Black flying fox, a species native to Australia, Papua New Guinea, and Indonesia) and the insect-eating bat Myotis davidii (David's mouse-eared bat, a species endemic in China).

"This is the first in-depth study of bat genomes. Our study provided important genomics insights into the unique biological features of bats," said Professor Wang, an expert in bat-borne viruses who was appointed Director of the Program in Emerging Infectious Diseases at Duke-NUS in July this year.

The large collaborative team from China, Denmark, Australia, U.S., and Singapore compared the two bat genomes with the genomes of other mammals, and found genetic clues that may account for the unique characteristics of bats.

Although bats are the second largest group of mammals, with over 1,000 species of bats documented so far, they are distinctive because they are the only mammals capable of sustained flight; other mammals such as flying squirrels glide but do not fly.

Previous research has shown that this ability to fly may be linked to high metabolic rates in bats. However, increased metabolism also elevates the amount of free radicals in living cells, resulting in DNA damage that is harmful to the bats.

Through their analysis of bat genomes, the researchers have now solved the mystery of how bats tolerate high levels of free radicals. It appears that bats have evolved mechanisms to overcome this toxic side-effect of flying, as they possess gene variants that help them minimise and repair DNA damage.

And here is where bats' ability to fly and their immunity against viruses intersect: the same gene variants that minimise DNA damage in bats may also provide protection against viruses, boosting their innate immune system to ward off such attacks.

Having a highly active immune system may explain why bats are natural hosts of many viruses such as Hendra, Nipah, Ebola, and SARS, yet rarely show any signs of infection. In contrast, when these viruses are transmitted to humans or other animals, the resulting illness is often severe and even fatal.

Bats are also known for their exceptional longevity which is unusual because of their small size and high metabolic rate. The researchers raise the intriguing possibility that the same mechanisms underlying the evolution of flight and viral immunity in bats may also be responsible for their life expectancy, although further research is required to establish this link.

Professor Wang hopes that the findings from this study will provide new research directions into infectious diseases, especially in the treatment, prevention, and control of emerging infectious diseases that affect both humans and livestock animals.

"Our findings highlight the potential of using bats as a model system to study infection control, tumour biology, and the mechanisms of ageing," said Professor Wang, who intends to continue studying bat-borne viruses in Duke-NUS, tapping on Duke-NUS' strengths in human infectious disease research for viral diseases such as dengue and influenza, and to explore new collaborative research in tumour biology with scientists in the Cancer and Stem Cell Biology Program at Duke-NUS.

Professor Wang is also a Science Leader for the CSIRO Office of the Chief Executive and Senior Principal Research Scientist at the CSIRO Australian Animal Health Laboratory (AAHL) in Geelong, Australia.

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