HOHHOT, Jan. 28 (Xinhua) -- Two white-tailed sea eagles, rare birds that enjoy top-level state protection in China, have been spotted in a wetland park in north China's Inner Mongolia Autonomous Region.

The rare birds were spotted at the Tao'erhe National Wetland Park earlier this month. Staff have strengthened daily patrols and monitoring in order to ensure they are not disturbed.

"The two eagles were spotted on Jan. 10. Since then, we have continued to closely observe their activities," said Xu Ming, a staff member with the park's management bureau.

This is the first time the species has been identified in the area, indicating that the local natural environment is improving.

White-tailed sea eagles are rare in the wild and listed on the Red List of Threatened Species of the International Union for Conservation of Nature (IUCN). They mainly breed in northern Eurasia and Greenland, and overwinter in the Democratic People's Republic of Korea, Japan, India, the Mediterranean Sea and northwest Africa.