A flock of swans flies over the wetlands of Otog Front Banner in Ordos city, in North China’s Inner Mongolia autonomous region. [Photo/ Ordos Release]

Around 1,000 migratory birds – including swans, grey cranes, mallards and egrets – have stopped to rest in the wetlands of Otog Front Banner in Ordos city, in North China’s Inner Mongolia autonomous region. [Photo/ Ordos Release]

A flock of birds flies over the wetlands of Otog Front Banner in Ordos city, in North China’s Inner Mongolia autonomous region. [Photo/ Ordos Release]