Our LOST ZOO opens “LOST DOLPHINARIUM”for the Chinese Baiji, the river dolphin from the Yangtze River

Only a few months ago we opened the first exhibition building in our LOST ZOO, the butterfly house “LOST PLANET”. Now again, we open for our visitors another, even bigger building, the Dolphinarium. It houses our pair of Yangtze River dolphins (Lipotes vexillifer) or Baiji as they are called too.

Landscape of Yangtze river, China(Click to view larger image).

The Baiji are freshwater dolphins that are endemic in the lower reaches of China's Yangtze and Quintangjiang rivers, and in the Poyang and Dongting lakes. They seems to be territorial and prefer to stay near large eddies that form next to sandbars.

The Baiji have a rather stocky body with a maximum length of 240 cm and a maximum weight of 160 kg. Females tend to be larger than males. The Baiji is bluish-grey in color becoming whitish on the underside, but seems white or greyish from a distance. Like other river dolphins, it has a very long, narrow beak with a slightly upturned tip. The rather small eyes are placed high up on the face. The dorsal fin is positioned low on the body and is triangular in shape. The flippers are rounded. In the zoological system the Baiji is the only species of its own genus and family.

But due to their cryptic habits, much of the Baiji’s behavior remains a mystery. They are usually found in pairs, which aggregate to form larger social units of about 10 individuals. Most of their time they spent in the vicinity of large eddies, where they search for fish during the day. At night they rest in areas of slow current.
In the turbid waters of the Yangtze, vision is mostly useless, so Baiji have poor eyesight but use a highly developed echolocation faculty to navigate and to find their prey. Their diet consists of mainly fish. They use their long beaks to probe muddy bottoms for food mainly in the shallow water near sandbanks or close to the mouth of tributaries of the river. Their dives are short, lasting only 10-20 seconds. They use their echolocation system also to communicate with one another using whistles and other acoustic signals.

The Baiji experienced a precipitous population decline throughout the late twentieth century. Tthere were thought to be about 400 individuals in the population in 1980, but only 17 were counted in 1997 and in 1999 fell to just four. The last verified Baiji reports are of a pregnant female found stranded at Zhenjiang in November 2001, and an individual photographed in the Tongling River section in May 2002. An extensive multi-vessel visual and acoustic survey in 2006 that covered the entire historical range of the Baiji in the main Yangtze channel failed to find any single Baiji. It is thought today that this river dolphin is now extinct.

There are three major factors that threatened the Baiji’s survival: dams and floodgates that block fish migration in the river's tributaries and lakes, fisheries accidentally killing dolphins, and boat propellers. Population numbers also declined through hunting and development of irrigation facilities. The heavy pollution and underwater noise characteristic of the Yangtze River also affects the Baiji.

Skeletons of Ganges river dolphin, Bolivian river dolphin and Amazon river dolphin(Click to view larger image).

However, the extinction of the Baiji is a national tragedy for China and an international disgrace. An earlier, more dynamic response to the species’ decline, both inside China and from the international community, might have kept some individuals alive today.

Therefore we are especially happy and proud that we keep now in the Lost Zoo’s new Dolphinarium this extreme rare river dolphin species and we hope that our pair in the future will give birth of many young Yangtze River dolphins.

Executive Curator
JURGEN LANGE