Baiji

Baiji

Mammalia

SCIENTIFIC CLASSIFICATION

COMMON NAME: baiji, Yangtze river dolphin
KINGDOM: Animalia
PHYLUM: Chordata
CLASS: Mammalia
ORDER: Cetacea
SUBORDER: Odontoceti
FAMILY: Platanistidae
GENUS SPECIES: Lipotes vexillifer

FAST FACTS

DESCRIPTION: Baijis have a fusiform body with a small head, tiny eyes, prominent melon and a long, narrow beak that is slightly up-curved at the tip. The dorsal fin of the baiji is low and triangular and the flippers are broad and rounded. The dorsal portion of the body is gray with whitish streaks from the ventral area extending into the face and head region.
FEMALE Females are slightly larger than males
SIZE:  
MALE To 2.29 m (7 ft 6 in)
FEMALE To 2.53 m (8 ft 4 in)
WEIGHT:
MALE 130 kg (290 lb)
FEMALE 170 kg (370 lb)
DIET: Small fish
GESTATION: Very little is known about reproduction, but gestation probably lasts 10-11 months
SEXUAL MATURITY: Unknown
LIFE SPAN: Unknown
RANGE: China's Yangtze River
HABITAT: Freshwater
POPULATION: GLOBAL Probably in the 10's or even less than 10; baijis are the world's most endangered cetacean
STATUS: IUCN Critically Endangered
CITES Appendix I
USFWS Endangered

FUN FACTS

1. Scientists have placed the baiji in the family Platanistidae, the river dolphin family. Four other species of small cetaceans also are in this family. They are:
  • boto (Amazon river dolphin) Inia geoffrensis, South America
  • franciscana (La Plata river dolphin) Pontoporia blainvillei, South America
  • Ganges susu (Ganges river dolphin) Platanista gangetica, India
  • Indus susu (Indus river dolphin) Platanista minor, Pakistan
2. Baiji is a Chinese word meaning "a white dolphin." This species is one of the most endangered cetaceans in the world, with a population numbering in the tens or fewer.

ECOLOGY AND CONSERVATION

Little is known about a river dolphin's natural history. However, several species are in danger of extinction. Threats to river dolphin populations include pollution, subsistence hunting, industrial development, dam construction, riverbank deforestation, over fishing, and incidental capture in commercial fisheries.

Why is the baiji endangered? Varying water levels in the Yangtze River due to industrial development have limited available habitat. Over fishing has decreased the baiji's food supply. Pollution harms both the dolphins and their prey. Baiji may be injured or killed by explosions during construction, and by boat propellers.

A number of baiji are caught and killed by illegal fishing devices called rolling hooks. These long, braided lines with numerous sharp hooks are meant to catch fishes. However, baiji also may become ensnared in the mass of hooks. Others become entangled in stake net traps.

The baiji has been protected by China since 1975. Chinese biologists began devising a protection strategy in 1986. By establishing reserve sites along the Yangtze River, scientists are hopeful that the species can be saved.

BIBLIOGRAPHY

Jefferson, T.J. Leatherwood, S. and M.A. Webber. FAO Species Identification Guide: Marine Mammals of the World. Rome. FAO, 1993.

Leatherwood, Stephen, and Reeves, Randall R. The Sierra Club Handbook of Whales and Dolphins. San Francisco: Sierra Club Books, 1983.

Nowak, Ronald M. (ed.). Walker's Mammals of the World. Vol. II. Baltimore: Johns Hopkins University Press, 1991.

Parker, S. (ed.). Grizmek's Encyclopedia of Mammals. Vol. IV. New York: McGraw-Hill Publishing Co., 1990.

Reeves, R. R., Stewart, B.S., Clapman, P.J., and J.A. Powell (Peter Folkens illustrator).National Audubon Society: Guide to Marine Mammals of the World. New York: Random House, 2002.

IUCN Animal Info - Baiji Page
http://www.animalinfo.org/species/cetacean/lipovexi.htm

http://animaldiversity.ummz.umich.edu