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| Sunday, 22 January 2006 |
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Features |  |
| News Business Features Editorial
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Environment H5N1, a distant mirage? by Shanika Sriyananda
With H5N1, which is the most dangerous strain of influenza to appear in decades, and still taking with it thousands of human lives, the innocent bird is quite unaware of possible threats to her life. After a flight of thousands of miles from the frozen West to Sri Lanka in search of better 'comforts', its life is now in danger due to 'unreasonable' doubts among villagers who still misunderstand the transmission of this deadly virus. Due to scientifically unproven 'beliefs', people have killed thousands of wild birds, like this great hunter, haphazardly in some parts of the world, in fear of getting infected with the deadly bird's flu.
With the dawn of the winter season, millions of wild birds start flying into their winter sites in Asia. The panic emerged in Sri Lanka with the start of the migratory season last September, and was further heightened with the 'discovery' of some carcases of migrant birds - 15 terns and 20 warders- in the Karagan lagoon in Hambantota, few months back. The season is on in Sri Lanka till April ends. Over 200 winter visitors, including water fowls, flemingos, waders like common sand pipers, sprints, gulls and terns, stop over in Sri Lanka on the Central and East Asian flyways during the season. They will leave for their original breeding places by end April. Majority of them invade wetlands of the country. "The H5N1 strain has specially been isolated from anseriforms - ducks, geese and swans, pelecaniforms - great cormorant, ciconiiforms - egrets and herons and charadriforms- gulls and waders. The virus has been found in one or very few individuals of at least 11 species of wild birds in Asia since 2003", says Dr. Channa Bambaradeniya, Cordinator of Asia Region Species Program of the World Conservation Union (IUCN). According to Dr. Bambaradeniya, the wild birds harbour various flu viruses but some are not pathogenic at all. He says that while some strains are mildly pathogenic and some belong to severe forms. " When the wild birds interact intensively with farm birds, the latter can be infected and mutated to more severe strains. It is like us getting colds. Among these aquatic birds viral infections are quite high", he adds. Every year, according to him, a healthy population of wild birds migrate from the north to avoid poor conditions associated with winter. "The birds that migrate are healthy but the sick cannot fly endless miles. So the likelihood of H5N1 strain spreading from migratory birds in the affected regions are quite remote or low", he points out adding that even though they are infected with the virus, they would die before they enter their winter destination. Dr. Bambaradeniya recalling an incident in Ratnapura, where the public panicked after seeing some large flocks of East Asian Swallower perched on top of power lines. They should not have feared about H5N1 and migratory birds. He says Sri Lanka does not have that much of free ranging poultry compared to others in the region. " Here, most of the farm birds are caged while in a majority of South Asian countries the farm birds - ducks, chickens, turkeys, goose- are kept in open places", he says. However, the doubts are still there. In China such an incident was reported where over 6,000 species of birds had been killed six months ago. "Attempts to cull wild birds in the current epidemic is unethical and ineffective", he says. The migratory season is still on and the birds, those who are actually free of the H5N1 virus, need care till they reach their own habitats. Dr. Bambaradeniya says that the most important thing to conserve wild birds and domestic poultry from the bird's flu is by making the public aware of the true facts. He also recommends improving surveillance, especially while carrying out monitoring in the wetlands, baning the import trade of wild birds species as pets, promoting research emerging diseases and wildlife health, educating people working with domesticated and wild animals on the health risks involved and best practices to prevent disease outbreaks, improving standards in poultry farms, farming and marketing practices and enhancing quality control and animal vaccines and decrease possible interaction between domestic poultry and wild birds through the use of shared water bodies. World's biggest fish 'shrinking' by Richard Black Whale sharks spotted off the coast of Australia are getting smaller, researchers have said. In a decade the average size has shrunk from seven metres to five metres. Whale sharks, the world's largest fish, are caught for food in some east Asian countries and Australian researchers suspect this is causing a decline. The fish is listed as "vulnerable", and one of the authors of the new study has described the new finding as "a very worrying sign". The data comes from ecotourism companies which run expeditions to watch whale sharks and swim with them in Ningaloo Marine Park off the north-west coast. "The eco-tourism industry logs the position and size and sex of every shark it swims with," said Mark Meekan of the Australian Institute of Marine Science (Aims). "We have obtained those datasets and analysed them over time," he told the BBC News website, "and essentially what we have seen in the last decade is a decline in average size of shark from seven metres to five metres. "Now if you consider that the sharks probably aren't sexually reproductive or mature until they're six or seven metres long - that's a very worrying sign." Looking for options Whale sharks ( Rhincodon typus ) are filter feeders, eating small marine organisms such as krill. They can live for up to 150 years, attaining lengths of up to 20m, and are believed to reach sexual maturity around the age of 30. Under the IUCN Red List of threatened species, they are categorised as "vulnerable" to extinction. "Whale sharks, like many other shark species, are highly vulnerable to over-exploitation due to their long lifespan and low reproductive rate," commented Callum Roberts of York University in the UK, who has researched whale sharks extensively in the Caribbean. "They have been added to CITES list of species threatened by international trade," he told the BBC News website, "but this will not protect them if they are caught by, for example, Taiwanese vessels and then consumed in Taiwan. "So whale sharks are at risk, and the decline in size might be due to capture of large sharks." There are also indications that the number of sharks visiting Australian waters may be decreasing, which would be additional evidence for a decline prompted by over-fishing. Aims researchers are running a tagging programme in an attempt to plot whale shark migration routes between Australia, Asia and the eastern coast of Africa. Specimens tagged in Australia have swum to Asian waters; last month a tag transmitted for days from the same location in Indonesia, apparently on land, leading researchers to suspect that the shark had been caught and the tag removed. Either the meat is eaten, or the giant fins used as advertising boards for restaurants serving shark fin soup; livers are used for oil, and cartilage in traditional Chinese medicine. Finding migration routes could help pinpoint areas where they are being caught. "Many of the people doing the fishing are just local villagers with no other option," said Mark Meekan. Longer term objectives of the Aims programme include finding out more about the life cycle of the whale shark. The biggest mystery concerns breeding and reproduction; males and females live in largely segregated communities, but must come together somewhere to breed. - BBC NEWS |
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| Produced by Lake House |
Perched on a barbed wire, near a shallow water patch in the wetland,
patiently waiting till a fish or frog appear, the foreign feathered friend
was a symbol of beauty until recently. Being a seasonal visitor to the area,
her fascinating looks and voracious hunting behaviour attracted many bird
lovers to the wetland for years during the migratory season. 
No proper cure is so far in sight and it is hard to believe that the flu
would not infect through wild birds, many Asians still blame and keep 'hawk
eyed' on migratory birds. 
