section_path: Wildlife/Other animals
section_name: Other animals
paragraph_text: Other animals
  
  Due to commercial use of the river, tourism, and pollution, the Yangtze is home to several seriously threatened species of large animals (in addition to fish): the narrow-ridged finless porpoise, baiji (Yangtze river dolphin), Chinese alligator, Yangtze giant softshell turtle and Chinese giant salamander. This is the only other place besides the United States that is native to an alligator and paddlefish species. In 2010, the Yangtze population of finless porpoise was 1000 individuals. In December 2006, the Yangtze river dolphin was declared functionally extinct after an extensive search of the river revealed no signs of the dolphin's inhabitance. In 2007, a large, white animal was sighted and photographed in the lower Yangtze and was tentatively presumed to be a baiji. However, as there have been no confirmed sightings since 2004, the baiji is presumed to be functionally extinct at this time. "Baijis were the last surviving species of a large lineage dating back seventy million years and one of only six species of freshwater dolphins." It has been argued that the extinction of the Yangtze river dolphin was a result of the completion of the Three Gorges Dam, a project that has affected many species of animals and plant life found only in the gorges area.
  
  Numerous species of land mammals are found in the Yangtze valley, but most of these are not directly associated with the river. Three exceptions are the semi-aquatic Eurasian otter, water deer and Père David's deer.
  
  In addition to the very large and exceptionally rare Yangtze giant softshell turtle, several smaller turtle species are found in the Yangtze basin, its delta and valleys. These include the Chinese box turtle, yellow-headed box turtle, Pan's box turtle, Yunnan box turtle, yellow pond turtle, Chinese pond turtle, Chinese stripe-necked turtle and Chinese softshell turtle, which all are considered threatened.
  
  More than 160 amphibian species are known from the Yangtze basin, including the world's largest, the critically endangered Chinese giant salamander. It has declined drastically due to hunting (it is considered a delicacy), habitat loss and pollution. The polluted Dian Lake, which is part of the upper Yangtze watershed (via Pudu River), is home to several highly threatened fish, but was also home to the Yunnan lake newt. This newt has not been seen since 1979 and is considered extinct. In contrast, the Chinese fire belly newt from the lower Yangtze basin is one of the few Chinese salamander species to remain common and it is considered least concern by the IUCN.
  
  The Yangtze basin contains a large number of freshwater crab species, including several endemics. A particularly rich genus in the river basin is the potamid Sinopotamon. The Chinese mitten crab is catadromous (migrates between fresh and saltwater) and it has been recorded up to 1,400 km (870 mi) up the Yangtze, which is the largest river in its native range. It is a commercially important species in its native range where it is farmed, but the Chinese mitten crab has also been spread to Europe and North America where considered invasive.
  
  The freshwater jellyfish Craspedacusta sowerbii, now an invasive species in large parts of the world, originates from the Yangtze.