A large flock of migratory birds flies above the downtown Harbin section of the Songhua River in Harbin, in northeastern Heilongjiang province, on Oct 7. This year, the Songhua River has seen more than 1 million migrating birds arrive. They have been making stops since the start of October, searching for food and rest during their trip to the warmer areas of southern China, to escape the cold. [Photo/IC]

A swarm of migrating birds flies over the Songhua River in Harbin, in Northeast China's Heilongjiang province, on Oct 7. [Photo/IC]