China's first law on wetland conservation has officially come into effect on June 1, with concerted efforts made in recent years to expand the forests of rare mangrove trees. Dongzhaigang National Nature Reserve in the country's largest tropical island Hainan Province is now home to a large number of red-flowered black mangroves, a once-endangered mangrove species. In recent years, numbers of this protected flora species have increased hugely, from 14 to nearly 1,000. Also, a total of 453 species of wild birds now live on the island.