Inbreeding has become one of the major factors threatening the survival of Chinese alligators, a world endangered species.

Chinese alligators near extinction

The number of Chinese alligators has rapidly risen since China began to artificially breed the rare creatures at the end of the 1980s, but their general health has deteriorated drastically, according to Wednesday's China Youth Daily.

Based on past research, experts have found that since alligators of the filial generation began to reproduce, abnormalities have begun to appear among the newborn, with some being under-sized and deformed, or having a protuberant cavity in the skull and curved backbone.

This has much to do with the inbreeding of Chinese alligators, experts note.

The paper reports that the Xuancheng Chinese Alligator Breeding and Research Center, in east China's Anhui Province, released more than 150 Chinese alligators into the wild in 1990 and the number of alligators in the wild at one stage reached 600.

But a recent survey carried out by the center shows that currently, fewer than 200 Chinese alligators have survived under the condition that this is no poaching or any other outside damaging activity.

At present, China has two Chinese alligator breeding centers, with more than 10,000 alligators, one in Xuancheng and the other in Changxing in east China's Zhejiang Province. The Xuancheng center alone has over 9,000, the largest group in the world.

The Chinese alligator protection zone covers 433 square kilometers, with only 41 hectares inhabited by Chinese alligators.

What is worse, experts say, the 41-hectare area has been divided into 13 small and isolated protection areas. The isolation has blocked gene exchanges and resulted in serious inbreeding of Chinese alligators, experts add.

Experts hold that it is imperative to break the isolation and expand the alligator protection zones, so as to promote mating between Chinese alligators from different habitats and save them from extinction.

Facts about Chinese alligators

Range--Water regions of the lower Yangtse River in China.

Habitat--Marshes, ponds, rivers and streams.

Size--Average 5-6 feet. Rarely larger than 7 feet.

Reproduction--10-50 eggs are produced and incubated for about 70 days.

Diet--Snails, frogs, and slow swimming fish.

Characteristics--This alligator differs from the American alligator in that it has a more blunt head with eyelids that have a bony plate. The Chinese alligator also has a bony belly plate that the American doesn't have. Its vision is extremely sharp out of water, but a third clear eyelid also allows them to see very well under water.

Behavior--These alligators have likely survived as long as they have because they are solitary and nocturnal, hiding during the day and hibernating in colder months in burrows. These burrows are often long and elaborate with multiple chambers.

(China Daily December 13, 2001 )