Migratory birds on the move

Flocks of birds fly over the Yalujiang Estuary Nature Reserve in Dandong, Northeast China's Liaoning province, April 25, 2011. Bird lovers found about 140,000 birds from 36 species in the reserve as they migrate to habitats in Siberia and Alaska to breed and raise their young. [Photo/CFP]

Flocks of birds fly over the Yalujiang Estuary Nature Reserve in Dandong, Northeast China's Liaoning province, April 25, 2011. [Photo/CFP]