Taiwan's water birds are one of the country's natural treasures. The West Coast's tidal mudflats, salt marshes and mangrove swamps attract both resident and migratory birds, with some locations boasting over 160 different species. Moreover, about half of the world's population of the internationally famous but endangered black-faced spoonbill spend their winters just north of Tainan in south Taiwan, making that city an ideal host for the Waterbirds 2005 Conference, held from November 25-27, 2005.

With recorded sightings of around 500 species – 150 or more species that live on the island year-round, and 15 endemic species not found in other countries – Taiwan's birds are so diverse that the field can be subdivided according to habitat.

Inhabitants of the high mountains such as the Mikado Pheasant, an species featured on the NT$1,000 bill, have received a lot of attention from academics and birdwatchers. Water birds – species found along rivers and in wetlands – are more numerous and visible, however, and due to recent fears that migrating birds could trigger an avian influenza pandemic, waterfowl are now being talked about more than ever before.

The Waterbirds 2005 Conference attracted a great deal of media attention, not only due to its focus on the migration of wild birds and avian diseases, but also because it was the first international meeting of its kind ever held in Asia.

Attended by around 400 scholars and wildlife enthusiasts, the conference was sponsored by the International Waterbird Society, BirdLife International, the U.S. Geological Survey, Environment Canada, the International Crane Foundation, the Wild Bird Federation of Taiwan and the Taiwan International Birding Society; with backing in Taiwan from Tainan City Hall, the Council of Agriculture, and the Government Information Office, which publishes this newspaper.

The first of the invited plenary speakers, Ron Ydenberg, began his address by pointing out that, when the organisers began setting up the event 18 months earlier, they had no idea how timely the theme of bird diseases would turn out to be.

Mr Ydenberg, director of the Centre for Wildlife Ecology at Simon Fraser University in British Columbia, Canada, provided an overview of the migration process. He said that birds migrate because the journey enhances their chances of survival: the attractions of better weather and a better supply of food outweigh the dangers likely to be encountered en route, such as predators and pathogens, and the energy needed to complete the migration.

However, around half of the world's shorebird species appear to be declining, said Mr Ydenberg. In North America, up to 80 percent of species are in decline. Even if extinction is not an immediate threat, falling numbers are significant in that a smaller population has less genetic variation, and is therefore more susceptible to disease outbreaks.

According to Mr Ydenberg, mudflats are especially attractive to birds, not only because such places usually have an abundance of food, but also because the lack of cover can make it more difficult for predators, such as birds of prey or feral cats, to approach without being noticed.

Shorebirds, he explained, suffer higher death rates due to predators at high tide than at low tide, simply because the rising waters force the birds to move closer to coastal cover, where the predators may be lurking. He did not say if this finding could impact conservation efforts on Taiwan's West Coast, where there is a longstanding policy of planting windbreak forests very close to the high-tide line.

Noting that a great deal has been learned in recent years about bird migrations in North America, Mr Ydenberg said, “Much less is known about East Asian flyways, and more needs to be learned”. He mentioned various hypotheses – including the suggestion that the stress and exhaustion of the migratory process makes birds more vulnerable to pathogens like H5N1 – that cannot be proved or disproved because of a lack of data. “There's a lot of work we have to do”, said Mr Ydenberg.

Moving on to the possibility that wild birds could transmit diseases to domesticated flocks, Ydenberg said that, to date, there has been no study of this scenario. But, he suggested, research in British Columbia that looked at both wild runs of salmon and their farmed counterparts might provide some idea of what is happening or what could happen. In Canada, Norway and Scotland, several wild runs of salmon have become extinct because of continuous cross-infection between commercial salmon and wild salmon. This implies that wild birds are more likely to be victims than vectors of disease – a point that was also made by other speakers during the conference.

Cases involving the transmission of Avian Influenza from birds to humans in Asia have been widely document. Leslie Dierauf, the second invited plenary speaker, explored the topic of the transmission of disease across different species in some detail.

Diseases “can flow across the landscape, and jump species”, said Ms Dierauf, a wildlife veterinarian and conservation biologist who is director of the U.S. Geological Service's National Wildlife Health Center in Madison, Wisconsin.

Ms Dierauf outlined the phenomenon of zoonosis – when a disease such as rabies crosses from the animal kingdom to infect humans – and noted that around 75 percent of new diseases appearing in humans are zoonotic.

According to Dierauf, there is no doubt that migrating birds can spread viruses: snow geese are carriers of avian cholera, a disease that is becoming more common in wild birds. One recent outbreak was in 2000 in South Korea, where more than 12,000 birds, 90 percent of them Baikal teals, died.

“Traditional practices in Asia put wild birds closer to domesticated flocks and pet birds”, said Dierauf. She cited the example of duck plague, which traveled from the Netherlands to poultry in the United States, and then into North America's wild bird population. She pointed out, however, that wild birds are more often victims than culprits.

Variables including climate change, industrialization, agriculture practices and antibiotic resistance mean the situation is constantly evolving, Dierauf explained. “Don't forget wildlife in the health equation. Be vigilant. Use wild birds as sentinels of environmental health”.

At the press conference that followed the delivery of these two speeches, Marco Lambertini of BirdLife International expressed concern that wild birds are being mistakenly portrayed as the main vehicle of disease transmission. Claiming that evidence of this was “extremely weak” or absent, he urged the media not to overstate the possibility of any link. “All evidence points to the root causes being in the poultry industry, the raising of chickens, geese and ducks”. In supporting his argument, Lambertini listed three facts: that no healthy migratory bird has checked positive for avian flu (although some dead birds have, suggesting migratory birds are not the disease vectors); that H5N1 is especially virulent, and usually leaves its victims unable to fly; and that previous outbreaks have all been traced to poultry farms or food products.

Moreover, he said, viewing wild birds as “prime suspects” is dangerous because it deflects attention from more probable causes, such as the movement of poultry and the pet-bird trade.

“The trade of wild birds and pet birds is a major concern”, he said, noting that such birds are often mixed with other birds, including poultry, in conditions that make transmission easier.

However, because viruses sometimes mutate, it is not impossible that wild birds will play a role in bird-flu transmission in the future, Lambertini said.

He called for an effective monitoring system that could investigate suspicious deaths of wild birds, because “wild birds are a good early warning system for problems in the environment”. Responding to those in Taiwan and elsewhere who have been urging people to avoid birds, Lambertini said that birdwatching is now more important than ever, because bird enthusiasts can help monitor avian health.

During the press conference, Robert Butler, a senior research scientist with Environment Canada's Canadian Wildlife Service, expressed optimism about the future for Taiwan's water birds. “The progressive attitude Taiwan has taken to conservation is a real model for the rest of Asia”, he said. Noting that Taiwan's government has moved to protect the uplands, and that several major rivers have been cleaned up, he stressed that conservation work in the country's densely populated and highly industrialized lowlands is now the biggest challenge.

Research papers presented on the second and third days of the conference underlined the black-faced spoonbill's role as a “flagship species” for conservationists. Eleven of the papers concerned studies of the black-faced spoonbill; no other species in Taiwan was the subject of more than a single study.

Among the findings presented were those by one Taiwanese team who analyzed mitochondrial DNA diversity to estimate the decline of the species, concluding that the current population is no more than one-ninth of what it once was. Another study by local researchers predicted that the global black-faced spoonbill population will rebound to 4,000 or more by 2014.

One paper implied that Taiwan's plan to massively expand wind power, which is billed as a “green technology”, may not bode well for the country's birds.

The coastline of Changhua County in Central Taiwan is an important habitat for wintering and breeding shorebirds, but it is also ideal for electricity-generating wind turbines. The paper noted that large numbers of birds pass through the area's existing wind farms, and evidence from Japan and elsewhere confirms that poorly sited turbines can jeopardize wild bird populations through habitat damage or collision with the blades. Adding hundreds of new turbines may create a new set of problems.

In early December, BirdLife International issued a press release asserting that, because avian migrations in the Northern Hemisphere have not been followed by any significant outbreaks of bird flu, “the most obvious explanation is that migrating wild birds are not spreading the disease”. Three weeks later, the same organization's suggestion that bird flu may be spread by the practice (in several countries, including Taiwan) of using chicken dung in fish farms was reported throughout the world.

The survival of the Mikado Pheasant and Taiwan's other endemic birds is in the hands of the island's people. However, many species of water bird have homes in different countries, and protecting only their habitats here will not help them survive in the long run. Cross-border protection efforts are required if these species are to be saved from extinction.

Taiwan is home to many different bird species, and its people are becoming more environmentally aware and internationally active. The country's bird experts and enthusiasts can expect to see a lot more of their overseas counterparts, during future conferences and dedicated birding trips.