"The duck knows first when the river becomes warm in spring" is a famous poem wrote by the well-known Chinese poet Su Shi from Northern Song Dynasty (960-1127) and a testament to reality.
On February 28, 2021, various ducks, including white-eyed pochards, mallard ducks, and red-throated loons, swam and foraged in the warm water in Baishahe Wetland of Qingdao City in east China's Shandong Province, announcing the coming spring.
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