Flocks of grey cranes forage in the Togtoh section of the Yellow River in Hohhot, capital city of North China's Inner Mongolia autonomous region. At present, the Yellow River Wetland in Togtoh county has entered its peak time for the winter arrival of migrating birds and some 10,000 of them have now gathered there. [Photo/Hohhot news network]

Grey cranes take wing over the Yellow River Wetland in Togtoh county. After years of conservation, it's transformed into a thriving integrated wetlands ecosystem. It is also an important stopping place for migratory birds on their way from north to south. [Photo/Hohhot news network]

Grey cranes soar into the air over the Yellow River Wetland. According to the observation and statistics for the Yellow River Wetland, there are currently more than 300 species of migratory rare birds there, including black storks, swans and gray cranes. [Photo/Hohhot news network]