Residents spotted a Yangtze finless porpoise entangled in rope with two plastic bottles in the waters downstream the Gezhouba Dam in central China's Hubei Province on Wednesday. Rescuers freed the marine animal by cutting the rope. The Yangtze finless porpoise is an endangered species under first-class state protection in China. Experts see its presence as an indicator of the ecological state of the Yangtze River.