Patrolman tells of his rewarding encounters with the 'smiling angel'

For more than four years, Zhu Guoqiang has patrolled the Yangtze River to monitor critically endangered finless porpoises, no matter how hard it rains or how strong the wind blows.

The 60-year-old, who has worked at the Nanjing Finless Porpoise Reserve in Jiangsu province since it was established in September 2014, walks or rides an electric bike for at least 32 kilometers on muddy roads alongside the river every day.

"The porpoises appear most frequently in the area that I patrol," Zhu said. "I record, for professional researchers, the places, numbers and times they show up."