The Yellow River Delta National Nature Reserve in Dongying, Shandong Province, is home to so many migratory bird species. It’s known as China’s “International Airport for Birds.”Since 1990, the number of species here has grown from 187 to 373, including rare and protected birds such as the oriental white stork  and Saunders’s gull. Senior engineer Zhao Yajie and her team are using advanced technology to protect this vibrant ecological haven for future generations.