KUNMING, Feb. 25 (Xinhua) -- An Aythya baeri, a critically endangered duck, was recently spotted in a national wetland park in southwest China's Yunnan Province, local authorities said Tuesday.

Duan Honglian, a senior engineer of the management center of Qinghuahai National Wetland Park in the city of Baoshan, said workers found a male duck during a patrol.

The migratory species is distributed in eastern and southeastern Asia. It mainly breeds in Russia's Far East and eastern China, and spends winters in southern China, Myanmar, Thailand, Bangladesh, India and Japan, according to Duan.

Since the 1990s, the population of Aythya baeri has dropped sharply due to habitat loss, over-hunting, human interference and other factors. They have been listed as "critically endangered" species by the International Union for Conservation of Nature.

The species mainly inhabits in lakes, reservoirs and marshes. They also live with other wild ducks and feed on roots, leaves, stems and seeds of aquatic plants, as well as mollusks, aquatic insects and crustaceans, Duan said.

Lin Lei, director of the management center of the wetland park, said wetlands in the park and the ecosystem have seen significant improvement in recent years, leading to the increase of species and population. A total of 209 species of birds have been recorded in the park.