SHENYANG, May 2 (Xinhua) -- With bulging bellies toward the sky, a group of spotted seals is sunbathing on the rocks in Liaodong Bay, northeast China's Liaoning Province.

Under top-class national protection in China, the spotted seal is the only pinniped marine mammal to breed in Chinese waters.

The seals come to Liaodong Bay from cold waters at high latitudes every December, prey and rest in the area, and return northwards in May.

From every January to March, about 200 cubs are born in the 10,000-square-kilometer ice area in Liaodong Bay.

The seals have to overcome various challenges after birth. People occasionally find stranded ones drifting with the ice sheets on the shore, triggering the monitoring, rescue, and releasing work.

More than 100 spotted seals inhabit the Sandaogou area of Panjin City every year. Since 2012, Panjin has set up a protection station about one km away from the gathering place of spotted seals to avoid disturbance from fishing boats and tourists nearby.

The sea ice near Sandaogou melts early in March, and cubs lying on the ice sheets and unable to live in the water for a long time will be put on the beach by their parents.

As these cubs are at risk of injury, team members of the protection station would patrol the coastline every day, observe the growth of the seals, and persuade fishing boats and tourists to stay away.

After years of persuasion, local fishermen gave up part of their working areas for spotted seals to rest, and they would contact the station if they spotted any seals that had been injured or stranded for a long time.

"Unless there are special circumstances, such as the spotted seal being injured or its parents being invisible within visual reach, the rescue team will bring the cubs back for rescue. Human assistance is not an end. We will eventually let them return to nature," said Wang Xiaobo, an official with the agriculture and rural affairs department of Panjin City.

"We rescued seven spotted seals in 2021. Three of them survived by themselves, so they were released into the sea directly. The other four were born prematurely and couldn't feed themselves," he said, adding that the population of the spotted seals monitored in the Sandaogou area has exceeded 250 this year.

The seals needing rescue are sent to the Liaoning Ocean and Fisheries Science Research Institute or an aquatic wildlife rescue center in Dalian City. There they receive treatment and rewilding training, including avoiding fishing nets and fishing boats, catching fish, and recognizing foreign objects.

The seals would be released into the wild once they meet the criteria. On May 10, 2021, 37 cubs were released into the sea in Dalian after they were assessed to meet the releasing conditions.

"We did routine blood examinations and biochemical tests for the seals and then checked the viruses that this kind of animal might contract. The 37 seals all met the standards in the assessment, so we released them all together this time," said Lu Zhichuang, a researcher with the research institute.

Panjin City has initiated a coastal wetland restoration project to gradually restore the 5,300-hectare mariculture pond to its original ecology, thus providing habitats for spotted seals and other marine life.

The population of spotted seals in the Liaodong Bay remains at around 2,000 while seeing an increasing trend.