A flock of black-necked cranes fly over the Dashanbao Black-neck Crane Nature Reserve in Zhaotong City, southwest China's Yunnan Province, Feb. 24, 2021. The Dashanbao Black-neck Crane Nature Reserve, established in 2003 for the endangered black-necked cranes, has witnessed over 1,400 black-necked cranes wintering here this year. In recent years, local authorities have taken a variety of measures such as ecological restoration and food source base construction to protect the habitat of black-necked cranes. (Xinhua/Hu Chao)