The Chinese alligator (; ), also known as the Yangtze alligator (), China alligator, or historically the muddy dragon, is a crocodilian endemic to China. It and the American alligator (A. mississippiensis) are the only living species in the genus Alligator of the family Alligatoridae. Dark gray or black in color with a fully armored body, the Chinese alligator grows to in length and weighs as an adult. It brumates in burrows in winter and is nocturnal in summer. Mating occurs in early summer, with females most commonly producing 20–30 eggs, which are smaller than those of any other crocodilian. The species is an opportunistic feeder, primarily eating fish and invertebrates. A vocal species, adults bellow during the mating season and young vocalize to communicate with their parents and other juveniles. Captive specimens have reached age 70, and wild specimens can live past 50. Living in bodies of fresh water, the Chinese alligator's range is restricted to six regions in the province of Anhui, as well as possibly the provinces of Jiangsu and Zhejiang. Originally living as far away from its current range as Japan, the species previously had a wide range and population, but beginning in 5000 BC, multiple threats, such as habitat destruction, caused the species' population and range to decline. The population in the wild was about 1000 in the 1970s, decreased to below 130 in 2001, and grew after 2003, with its population being about 300 as of 2017. Listed as critically endangered by the International Union for Conservation of Nature, multiple conservation actions have been taking place for this species. The Chinese alligator has been a part of Chinese literature since the third century. In the late 1200s, Marco Polo became the first person outside of China to write about it. In some writings, the Chinese alligator has been associated with the Chinese dragon. Many pieces of evidence suggest that the Chinese alligator was an inspiration for the Chinese dragon. History and taxonomy Chinese alligators were mentioned in Chinese literature very early; for example, in the Classic of Poetry, whose poems were composed between the 11th and 7th centuries BCE. Marco Polo was the first person outside of China to write about the alligator, when he came to China and saw it in the late 1200s. He said that the alligator lived in "caverns" in the day and hunted at night, and that humans targeted