Scientists have successfully cultivated a specific plant as food sources for white cranes wintering at Poyang Lake, enhancing their habitat quality and reducing the need for them to forage in farmers' rice paddies.

Poyang Lake, located in east China's Jiangxi Province, is the largest freshwater lake in the country. Every year during the migratory season, over 95 percent of the world's white cranes, along with hundreds of thousands of swans and other migratory birds, fly to the lake to winter.

Over the recent years, however, frequent extreme weather events such as high temperatures and droughts have negatively impacted the ecology of Poyang Lake. This includes a significant reduction of submerged vegetation, resulting in a food shortage for white cranes and forcing them to seek other foraging areas like rice paddies and lotus ponds.

In response, after multiple rounds of research and ecological assessment, scientists identified Vallisneria spinulosa Yan as the appropriate food for white cranes and started the cultivation process. The plant is a native species of Poyang Lake, known for its nature of producing winter buds preferred by migratory birds.

However, Vallisneria spinulosa Yan has extremely low commercial value, making its seed sources virtually unavailable on the market.

In 2020, scientists started from scratch, obtaining seeds through manual digging in riverbeds.

"Basically, we faced major obstacles every year. In 2020, we found nowhere to purchase the seeds, so we had to dig them up from the riverbeds. In 2021, although we already cultivated the plants, flooding brought in grass carp that ate them. In 2022, we fought with high temperatures and drought conditions. In 2023, we began our cultivation efforts in the No. 1 pond. Through on-site sampling, we found that we had successfully cultivated the winter buds, and they were in large amount," said Luo Hao, a researcher at the Poyang Lake National Nature Reserve.

In November this year, the scientists conducted an inspection of their cultivation work. Multiple on-site sampling results showed that the average winter bud content reached about 850 per square meter, over 90 times the initial planting amount of nine winter buds per square meter.

"Last year, we introduced 400,000 plants into each of the two lakes in the reserve, Changhu Pond and Xianghu Lake, and the vegetation recovery in both lakes is progressing well. This year, we have already observed signs of white cranes and tundra swans in both lakes," said Luo.