Frightened by a historic drought, local authorities in China have renewed controversial plans to dam the country’s largest freshwater lake.
But environmentalists warn that damming Poyang Lake, a winter stopover for more than half a million birds, would threaten the fragile ecosystem and the endangered birds and other wildlife it harbors.
China is currently chairing the UN biodiversity talks in Montreal, billed as the “last best chance” to save the planet’s species and their habitats from irreversible human destruction.
The Poyang Dam, which is slowly recovering after shrinking to less than a third of its usual size, shows just how difficult such efforts are in China.
Conservationist Zhang Daqian said that, if realized, the 3,000-meter-long gate across one of the lake’s channels would cut it off from the Yangtze River, “leaving Poyang a dead lake.”
China has built more than 50,000 dams in the Yangtze basin in the past 70 years, including the Three Gorges dam, which came in the face of widespread opposition from environmentalists.
During the same period, at least 70 percent of the river’s wetlands have disappeared, according to data from the Ministry of the Environment.
When the project was initially raised, complaints from environmentalists managed to shelve it.
But the looming specter of droughts, which are becoming more frequent and severe in the area thanks to climate change, has upset the calculation.
Poyang supplies water to Jiangxi province’s 4.8 million people, and the local government says building dams will conserve water, irrigate more farmland and improve navigation.
An environmental impact assessment (EIA) published in May gave experts just two weeks to review 1,200 pages of documents and file complaints.
In a normal wet season, Poyang can be three times the size of Los Angeles.
Its marshes are the main winter feeding grounds for hundreds of thousands of birds that fly south to escape the cold each fall.
They include the critically endangered Siberian crane, whose population has dwindled to about 4,000.
This year’s drought was the worst in 70 years, and the region entered the dry season three months earlier than usual.
Still, hundreds of birds were gathering in small pools of water left in the cracked river bed when AFP visited a reserve in Yongxiu county in early November.
“Migratory birds keep coming to Poyang, because it’s their usual winter home,” said an employee surnamed Chen, peering across the dry expanse littered with empty mussel shells and fish skeletons.
“But there are no fish or shrimp for them to eat. Many birds flock to the nearby fields and farmers have been told to leave some of their rice paddy unharvested for the birds,” Chen said.
Officials have pumped water from nearby reservoirs to form small butterfly-shaped watering holes for the birds.
“There are no conflicts (between residents and birds), because migratory birds are nationally protected animals and people will not harm them,” He Fangjin, an employee of another wetland park, told AFP.
At nearby Zhupao Hill, a popular bird-watching spot, some 90,000 migratory birds were observed from October to early December, up from 62,000 birds in the same period last year.
It is not clear what stage of development the dam is currently in and neither local authorities nor the environment ministry responded to questions from AFP.
But if they went ahead, the gate would disrupt the lake’s natural ebb and flow with the Yangtze, potentially threatening tidal flats where birds feed, said Lu Xixi, a geography professor at the National University of Singapore.
The loss of natural water circulation could also harm Poyang’s ability to remove nutrients, risking algae buildup that could disrupt the food chain, Lu added.
The dam could also affect another critically endangered species that calls the lake home: the Yangtze finless porpoise. Just over 1,000 remain in the wild.
During the drought, the porpoises took refuge in the very channel that the dam would cut, a ranger with the Beijing Grassland Environmental Protection League, which has patrolled the lake for more than a month, told AFP.
The Beijing-based Friends of Nature said the dam’s EIA did not make a comprehensive assessment of whether it would block porpoise migration.
“Without full scientific evidence and before the environmental risks are eliminated, the project should not go ahead,” the group said in a statement.
© 2022 AFP
Citation: Dam Plans Threaten China Migratory Bird Sanctuary (2022, December 18) Accessed December 18, 2022, at https://phys.org/news/2022-12-threaten-china-migratory-bird- haven.html
This document is subject to copyright. Apart from any fair dealing for private study or research purposes, no part may be reproduced without written permission. The content is provided for informational purposes only.