The number of black-faced spoonbills in Hong Kong has dropped for the first time in nearly a decade and experts are at a loss to explain the decrease. An annual global census on the endangered species, released yesterday, found there were 335 black-faced spoonbills in the city this year, down 9 per cent from the 369 recorded last year. The worldwide total stood at 2,041 this year, down slightly over the previous year. 'We are not sure why there are fewer black-faced spoonbills in Hong Kong. It might be a normal fluctuation or there might be some birds flying from the city to Taiwan for the winter,' said Yu Yat-tung, co-ordinator of the survey, organised by the Hong Kong Bird Watching Society. Mr Yu also cautioned that the survey might also be inaccurate because it relied on a manual count. The black-faced spoonbill, which has a spoon-like black bill and a yellow patch beside its eyes, is found mainly along the coast in Southeast Asia. It was once listed by the conservation group BirdLife International as a 'critically endangered' species in the 1990s after the worldwide total plunged to between 300 and 500. In Hong Kong, the birds are commonly seen in the Wetland Park in Yuen Long and the Mai Po Marshes near Deep Bay. According to the survey, Taiwan, which has the most spoonbills, recorded a 7 per cent increase this year, while the mainland, including Fujian, Guangdong and Hainan provinces and Shanghai, saw a 20 per cent drop. Cheung Ho-fai, president of the Bird Watching Society, said urbanisation had always been a big threat to the bird. 'Development in southeast China is faster than it is in other places,' he said. 'The birds have a smaller habitat for breeding and hunting.' He also expressed concerns over a high-rise development planned in Fung Lok Wai near the Mai Po Nature Reserve. 'If you go to have a look, you'll find some of the ponds near Fung Lok Wai have already dried up. It will be harder for the birds to hunt for food,' he said. The Mai Po Nature Reserve will reopen today after a three-week closure due to H5N1 virus found in a dead grey heron there. A spokesman for the Agriculture, Fisheries and Conservation Department said yesterday that no more cases of bird infection had been found near the nature reserve in the past three weeks. However, he reminded the public to continue to be alert.