Audubon Technique Benefits Rare Seabird

By aperry
Published October 04, 2013
Until this year, there were only two known breeding colonies of the critically endangered Chinese Crested Tern Thalasseus bernsteini, both in island archipelagos close to the east coast of the People's Republic of China: the Matsu Islands off the coast of Fujian province, and the Wuzhishan Islands off Zhejiang province. The species was once thought to be extinct, with no recorded sightings since the 1930s until a few birds were rediscovered in the Matsu Islands in 2000. Exhaustive surveys following rediscovery have led to population estimates of fewer than 50 individuals, leading many experts to consider the species to be the most endangered seabird in the world.

This summer an innovative tern colony restoration project, with technical assistance from faculty and students in the Department of Fisheries and Wildlife at Oregon State University, has apparently established a third nesting colony, a major advance for the conservation of the species. The OSU group advised on tern restoration techniques, originally developed by Steve Kress with the National Audubon Society, and used extensively by OSU to restore tern colonies in Oregon and elsewhere on the West Coast.

Earlier this year, a small island called Tiedun Dao in the Jiushan Islands – an archipelago where Chinese Crested Terns used to breed – was chosen for colony restoration. The restoration team expected it would take some years before there was any hope of attracting the birds back. Their plan was to use decoys and playback tern calls to initially attract Greater Crested Terns Thalasseus bergii to Tiedun Dao. It was hoped that the Greater Crested Terns would initially colonise the island, their numbers would then gradually grow, and that Chinese Crested Terns, which have always been found nesting within large colonies of Greater Crested Terns, might eventually follow too.

Project biologists were amazed by the results. In the first year of restoration, a substantial new colony of Greater Crested Terns had formed on Tiedun Dao, raised hundreds of young terns and, among them, at least one Chinese Crested Tern chick successfully fledged.

In early May 2013, a team from the Xiangshan Ocean and Fishery Bureau, the Jiushan Islands National Nature Reserve, the Zhejiang Museum of Natural History, and Oregon State University cleared vegetation and placed 300 tern decoys on Tiedun Dao. Solar powered playback systems were installed among the decoys broadcasting contact calls of Greater and Chinese Crested Terns recorded at the Wuzhishan Islands colony.

An international team including members from BirdLife International, the Hong Kong Bird Watching Society, Oregon State University, the Zhejiang Museum of Natural History, and the Jiushan Islands National Nature Reserve visited Tiedun Dao in mid-July. To their surprise and delight, a few Greater Crested Terns were seen flying above the decoys. Their numbers grew to several hundred within a few days and by the end of July 2,600 Greater Crested Terns had been recorded and hundreds of pairs had laid eggs and begun incubation. To the restoration team’s amazement, among them were 19 adult Chinese Crested Terns – the highest single count in one location since the species’ rediscovery in 2000. At least two pairs also laid eggs and initiated incubation.  Despite typhoons and the late season start to their breeding, by late September at least 600 Greater Crested Tern chicks, and at least one Chinese Crested Tern chick, had successfully fledged.

Local officials are very pleased with the success of the project and are committed to future protection of the nascent colony. Mr. Yu Mingquan, Deputy Director of the provincial Xiangshan Ocean and Fishery Bureau said, “We will do our best to ensure good management of the Jiushan Islands National Nature Reserve and we also hope to receive more support for the conservation of the tern colony here in Xiangshan.”

“The success on Tiedun Dao is a landmark for contemporary conservation in this region.” responded BirdLife’s Senior Asia Conservation Officer, Simba Chan. “No one dared imagine that the first year of such a challenging restoration project would be so successful, it just goes to show what can happen with a good idea, strong local commitment, and a bit of luck.”

Dan Roby, Professor of Wildlife Ecology at Oregon State University, also commented, “The success of this restoration project is the first critical step toward saving the Chinese Crested Tern from extinction, and brings new hope for an eleventh-hour rescue of this charismatic seabird species. It is also further testimony to the efficacy of the seabird restoration techniques developed by Steve Kress, VP for Bird Conservation at the National Audubon Society.  He also acknowledge the extraordinary determination and dedication of those in China who implemented these techniques so successfully, especially the Xiangshan Ocean and Fishery Bureau, the Zhejiang Museum of Natural History, and BirdLife Asia.”  Steve Kress added “hands-on projects such as the Tiedun Dao tern project demonstrate how effective wildlife stewardship at the local level can have dramatic success with worldwide impact.”

The restoration project is sponsored by several international funders, including the Japan Fund for Global Environment, the US Fish and Wildlife Service (Wildlife Without Borders), Oregon State University, the USGS-Oregon Cooperative Fish and Wildlife Research Unit, the Ocean Park Conservation Foundation Hong Kong, and BirdLife International supporter Mark Constantine. In China, the Xiangshan Ocean and Fishery Bureau, the Jiushan Islands National Nature Reserve, and the Zhejiang Museum of Natural History provided vital matching funds. These three Chinese organizations also coordinated the conservation action in China and provided significant logistical support there that helped make the first year of the project such a resounding success.