Migratory birds from Russia and Thailand were found along the western coast of South Korea, highlighting the region's ecological value as a key migratory route for several bird species, official sources said Sunday.

The short-tailed bush warbler, also nicknamed the "Asian stubtail," was spotted at Taeanhaean National Park, according to an official at the Korea National Park Service. He said the bird was wearing a special ring on its foot attached by the Bird Ringing Center, located in the Maritime Province of Siberia, Russia.

The fully grown bird was discovered in Hakampo on Taean Peninsula on April 30, two years and eight months after the Russian bird institute tagged it. The BRC is about 860 kilometers away from Taean.

Local ornithologists estimate that the warbler stopped at Taean on its way north after spending a warm winter in Southeast Asia.

The discovery not only generated interest among ornithologists but also the general public, since the Taean Peninsula experienced one of the worst crude oil spills in Korean history in late 2007 caused by a tanker accident.

Earlier on June 2, the black-browed reed warbler, another species of migratory warbler, was spotted in the same area in Taean.

This marks the first time that the species from Thailand was officially spotted in South Korea. 

The park service found the bird wearing an identification ring around its leg, attached by a Thai national park agency in Mannai Island, Rayong, on May 4. The Thai island and Taean are about 3,640 kilometers apart.

Black-browed reed warblers spend the winter in warm southern China, Thailand and Myanmar and migrate back to cooler regions, including northeastern China and Sakhalin in Russia, during summer.

The bird is rarely found in South Korea.

"We will expand bird-ring research with our international counterparts to determine new migratory routes for birds," a national park official said. He said such work would help them better preserve the natural habitats of migratory birds. (Yonhap)