Baiji

## Description

The baiji (Chinese: 白鱀豚; pinyin: báijìtún (help·info), Lipotes vexillifer, Lipotes meaning "left behind", vexillifer "flag bearer") is a possibly extinct species of freshwater dolphin. It is thought to be the first dolphin species driven to extinction due to the impact of humans. This dolphin is listed as “critically endangered: possibly extinct” by the IUCN, has not been seen in almost 20 years, and several surveys of the Yangtze have failed to find it. In China, the species is also called the Chinese river dolphin, Yangtze river dolphin, Yangtze dolphin and whitefin dolphin. Nicknamed the "Goddess of the Yangtze" (simplified Chinese: 长江女神; traditional Chinese: 長江女神; pinyin: Cháng Jiāng nǚshén ), it was regarded as the goddess of protection by local fishermen and boatmen. It is not to be confused with the Chinese white dolphin (Sousa chinensis ) or the finless porpoise (Neophocaena phocaenoides ).

The baiji population declined drastically in decades as China industrialized and made heavy use of the river for fishing, transportation, and hydroelectricity. It has been credibly claimed, after surveys in the Yangtze River during the 1980s, that baiji could be the first dolphin species in history that humans have driven to extinction. A Conservation Action Plan for Cetaceans of the Yangtze River was approved by the Chinese Government in 2001. Efforts were made to conserve the species, but a late 2006 expedition failed to find any baiji in the river. Organizers declared the baiji functionally extinct. The baiji represents the first documented global extinction of an aquatic "megafaunal" vertebrate in over 50 years since the demise of the Japanese sea lion (Zalophus japonicus ) and the Caribbean monk seal (Neomonachus tropicalis ) in the 1950s. It also signified the disappearance of an entire mammal family of river dolphins (Lipotidae). The baiji's extinction would be the first recorded extinction of a well-studied cetacean species (it is unclear if some previously extinct varieties were species or subspecies) to be directly attributable to human influence.

Swiss economist and CEO of the baiji.org Foundation August Pfluger funded an expedition in which an international team, taken in part from the National Oceanic and Atmospheric Administration and the Fisheries Research Agency in Japan, searched for six weeks for signs of the dolphin. The search took place almost a decade after the last exploration in 1997, which turned up only 13 of the cetaceans.

In August 2007, a Chinese man reportedly videotaped a large white animal swimming in the Yangtze. Although the animal was tentatively identified as a baiji, the presence of only one or a few animals, particularly of advanced age, is not enough to save a functionally extinct species from true extinction. The last known living baiji was Qiqi (淇淇), who died in 2002. The World Wildlife Fund is calling for the preservation of any possible baiji habitat, in case the species is located and can be revived.

## Appearance

The Baiji is a possibly extinct species of freshwater dolphin and is thought to be the first dolphin species driven to extinction due to the impact of humans. The Baiji is pale blue to gray on the dorsal (back) side, and white on the ventral (belly) side. It has a long and slightly-upturned beak with 31-36 conical teeth on either jaw. Its dorsal fin is low and triangular in shape and resembles a light-colored flag when the dolphin swims just below the surface of the murky Yangtze River, hence the name "white-flag" dolphin.

## Distribution

Baiji are native to the Yangtze River of China. Historically they occurred in the middle and lower reaches of the Yangtze from Yichang in the west to the mouth of the river, near to Shanghai, as well as in Poyang and Dongting lakes, and the smaller Qiantang river to the south.

## Behavior

Baiji are diurnal and social animals. They occur in pairs or small groups of about 10 individuals spending the day in search of fish. They are usually quiet and shy and difficult to approach. When escaping from danger, these dolphins can reach 60 km/h (37 mph), but usually stay within 30 to 40 km/h (19 to 25 mph). Because of the poor vision, baiji rely primarily on sonar for navigation. The sonar system also plays an important role in socializing, predator avoidance, group coordination, and expressing emotions.

## Diet

Baiji are carnivores (piscivores) and feed on a wide variety of freshwater fish.

## Reproduction

The mating system of baiji is unknown. Females breed once every two years and the peak calving season usually occurs from February to April. The gestation period lasts 10-11 months after which females give birth to a single calf. The young measure around 80-90 centimeters (31-35 in) at birth, and are nursed for 8-20 months. Males reach reproductive maturity at age four, while females are ready to breed when they are six years old.

## Population

### Population threats

The baiji population declined drastically in decades as China industrialized and made heavy use of the river for fishing, transportation, and hydroelectricity. It has been credibly claimed, after surveys in the Yangtze River during the 1980s, that baiji could be the first dolphin species in history that humans have driven to extinction. The main threats to the species included a period of hunting by humans during the Great Leap Forward, entanglement in fishing gear, the illegal practice of electric fishing, collisions with boats and ships, habitat loss, and pollution. Further studies have noted that a lack of information on the baiji's historical distribution or ecology, the environmental impact of the construction of the Three Gorges Dam on the living space of the baiji, and the failure to act for the protection of the baiji are also threats to the species. In August 2007, a Chinese man reportedly videotaped a large white animal swimming in the Yangtze. Although the animal was tentatively identified as a baiji, the presence of only one or a few animals, particularly of advanced age, is not enough to save a functionally extinct species from true extinction. The World Wildlife Fund is calling for the preservation of any possible baiji habitat, in case the species is located and can be revived.

### Population number

The IUCN Red List and other sources don’t provide the total number of the baiji population size. Currently, this species is classified as Critically Endangered (CR) on the IUCN Red List and its numbers today are decreasing.

## Fun Facts for Kids

The name Baiji means 'white fin' in Chinese, it means 'white-finned dolphin'.

Per Chinese folklore, a beautiful young girl is said to have lived with her stepfather on the banks of the river Yangtze. He was evil, and a greedy man out for his own self-interest. One day, he took the girl on a boat, intending to sell her on the market. Out on the river, though, he became infatuated with her beauty and tried to take advantage of her. But the girl freed herself by plunging into the river whereupon a big storm came and sank the boat. After the storm had thus settled, people saw a beautiful dolphin swimming - the incarnation of the girl - which became known as the "Goddess of the Yangtze". The baiji, in the region of Yangtze, is regarded as a symbol of peace and prosperity.

Nicknamed the "Goddess of the Yangtze", the baiji was also regarded as the goddess of protection by local fishermen and boatmen.

The Baiji is not closely related to any living species of a dolphin; it has diverged from the ancestors of the La Plata dolphin and Amazon River dolphin during the Miocene, estimated to be around 16 million years ago.

The closest known relative of the Baiji is Parapontoporia, native to the Western Coast of North America during the Latest Miocene and Pliocene.

The Baiji was one of five species of dolphins that have made freshwater their exclusive habitat.