A baiji, also known as the Yangtze River dolphin, is a recently decimated species of freshwater porpoise found only in the Yangtze River in China. These pale, long-beaked cetaceans were nearly blind and relied heavily on their sonar to find food and navigate the river. Due to large-scale dredging and damming as well as overfishing of their food source and the mammals themselves, the baiji has been declared functionally extinct. A survey in December 2006 found no live specimens.
Baijis were one of four known species of freshwater dolphins. An adult weighed 300-510 pounds (135-230 kg) and were around eight feet (2.5 m) in length, and had a long beak and a white underbelly. The baiji fed mostly on small freshwater fish and was found originally in a 1,000-mile (1609 km) stretch of the Yangtze River, including tributaries and the Dongting and Poyang Lakes.
The baiji lived in groups of three or four and preferred quiet eddies near both sandbars and meanders and deep waters in the river. Only one young was born at a time, and gestation lasted 10-11 months. The animal probably had a lifespan of around 25 years, and due to the two-year gap between births did not reproduce quickly. Observed communication consisted of whistles and clicks, similar to other dolphin species.
During the Great Leap Forward from 1958 to 1961, traditional veneration of the baiji as the “Goddess of the Yangtze” ended, and they were hunted for food and traditional medicine. Environmental changes, including the Gezhouba Dam Project, dredging the river, and pollution by industrial waste, severely damaged the dolphin’s habitat and that of its prey. Electrofishing threatened it and reduced its food supply. Noise pollution caused by boats confused its sonar, and collisions may have injured many of the animals.
In the 1970s, China became aware of the plight of the baiji and created protection organizations, but none were able to keep an animal in captivity for long. During November and December of 2006, thirty researchers undertook a six-week, 2,000 mile (3219 km) survey of the animal’s habitat, but turned up no live specimens. The baiji were then declared functionally extinct.
Later in August 2007, a sighting of an animal later confirmed as a baiji took place in eastern China's Anhui Province and was captured on video. There is little hope of a breeding population left there, however. The finless dolphin, another native cetacean, is now the target of an aggressive conservation effort, and calves have been successfully bred and born in captivity.