DALIAN -- Four harbor seals returned to the wild by Chinese scientists one month ago have sent sensor signals suggesting that they have used their natural instincts to find ways to approach wild seal groups living in northeast Asian waters.

Lu Zhichuang, a researcher with the Liaoning Institute of Marine Fisheries Research, said on Tuesday that seals tagged with satellite sensors separated after being released to the sea in Liaodong Bay in northeast China's Liaoning Province on June 18.

However, the seals are now moving toward the same destination -- Baengnyeong Island in the Republic of Korea, which is a summer migration habitat for seals.

"They could reach the island and find other wild seal groups within a week, if everything goes well," said the scientist.

He said one of the two groups -- two artificially raised seals -- chose to migrate together in seas near the Korean Peninsula. The other two seals swam to seas near China's Shandong Peninsula.

Six seals were originally released in Liaodong Bay. However, researchers have lost track of two of the seals, Lu said. All six of the seals were released under a research program co-sponsored by Sun Asia Sea World in Liaoning's city of Dalian.

Lu said that three of the seals were bred in captivity at Sun Asia Sea World and have never swam in a natural sea environment.

"The information we can gather from the released seals can help us to better understand their migration habits and their preferred habitats," he said.

The harbor seal is under second-class state protection in China.

Lu said the scientists hope to see the tagged seals return to Liaodong Bay in November, as it is a winter habitat for seals.