Flocks of black-headed gulls were seen busy hunting fish at the Binzhou Lake in Daqing City, northeast China's Heilongjiang Province on October 18, 2020. As the temperature drops quickly, migratory birds prepare for their annual southward long-distance migration, and one of the most important things is to make sure they have enough energy. Therefore, black-headed gulls try to eat as much fish as they can before taking off.

(All images： CFP)