BREEDING GIANT PANDAS IN CAPTIVITY

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*http://www.chinadaily.com.cn/english/doc/2005-11/25/content_498027_3.htm*

*Births of pandas in captivity hit record number

**(Washington Post)

Updated: 2005-11-25 14:57*

 

Chinese scientists have logged a record number of giant panda births in

captivity this year through improved artificial insemination techniques and

better understanding of how the reclusive but universally appealing creature

lives and mates.

 

 

Yaya, a female giant panda, cradles her cub, Jingjing, also a female, who

was born at the Chengdu Giant Panda Breeding Research Base in China's

Sichuan province Aug. 30. It was one of three live births at the facility

this season. [Chengdu Giant Panda Breeding Research Base]

 

The result of hard science by no-nonsense researchers, the increased

birthrate is good news for the many children and soft-hearted adults around

the world who delight in the sight of pandas, with their distinctive black

and white fur, sitting back and tranquilly munching on bamboo leaves.

 

The pandas slouching about their compound here at the Chengdu Giant Panda

Breeding Research Base in central China's Sichuan province did not seem

particularly moved by their species' accomplishment. But at least 19 pandas

were born -- and have survived -- this season in a pair of Chinese research

facilities, officials said, the highest number since scientists here and

abroad began trying to foster reproduction of the endangered animal through

artificial insemination about 40 years ago.

 

Several more were born in research centers and zoos in other countries,

including twin cubs born Aug. 23 in the Adventure World Park Zoo in western

Japan's Wakayama prefecture, of which only the female lived, and Tai Shan, a

male cub who was born at Washington's National Zoo on July 9 and is reported

to be thriving. In all, up to 25 giant pandas were born and survived in

captivity around the world during this summer's birthing season, according

to the State Forestry Administration and Chinese specialists.

 

A survey last year by the State Forestry Administration showed that the

number of giant pandas living in the wild has also risen, to an estimated

1,590, up from 1,110 in the 1980s. Most roam the isolated hills of China's

Sichuan, Gansu and Shaanxi provinces, eating bamboo and staying as far as

they can from human beings. The population has grown over the last several

years, scientists said, because the government has turned large parts of the

panda's habitat into reserves where logging and farming are forbidden.

 

This marks a turnaround from the years when China's ever-expanding human

population intruded on the hillsides where giant pandas live and breed,

turning them into an endangered species. The panda, whose markings and

chubby contours seem to invite cuddling, in fact is easily distressed by

contact with human beings, research has shown, and it seems to thrive best

when left alone among the bamboo stands of central China's misty mountains.

 

Partly for that reason, scientists for years have had trouble getting

captive giant pandas to reproduce. With a limited number of males to choose

from in captivity, picky females often resisted advances, they found, and

males in contact with humans at zoos and research institutes seldom seemed

to show much ardor. Fewer than a third of captive pandas have mated

naturally.

 

As a result, intensive efforts have been under way since the 1960s to breed

pandas by artificial insemination. As techniques and knowledge improve, the

artificial route has begun to show better results, particularly since the

turn of the century.

 

The Chengdu facility's director, Zhang Zhihe, held out the promise of

repeating and perhaps improving on this year's productive season in coming

years. " Gradually, from year to year, we have begun to know more about giant

pandas, their genetic makeup, their habits, their nutrition and so on, " he

said in an interview. " And the more we know about them, the more we can help

them reproduce. "

 

Three of this year's births in China took place at Zhang's institute, which

houses 48 pandas in a series of compounds strewn with bamboo stalks and

built to resemble the hillsides where pandas live naturally. Sixteen other

births, including two instances of twins, occurred at the Wolong Giant Panda

Breeding and Research Center, a sister institute 80 miles northwest of

Chengdu and nearer to the panda's natural habitat.

 

The biggest reason for this year's record and the hope of more high numbers

in the future, Zhang said, is that a growing number of captive pandas are

reaching mating age, 5 years old for females and 6 or 7 for males.

 

The broader the circle of possible suitors for each female, the higher the

chances that she will accept a male for natural fecundation, said Zhang, a

veterinarian and geneticist by training. And if artificial insemination is

still necessary, as is likely, he added, the wider selection of males will

mean a wider gene pool and stronger animals with a higher survival rate.

 

The goal, Zhang added, is to reach a point where the captive pandas

reproduce naturally and become numerous and strong enough that they can be

released into the wild. " But we still have a long way to go, " he said,

" because if we want to have a self-sustaining panda population, we need a

bigger pool of individuals, because we need a relatively high genetic

diversity. "

 

A key step came in 1980, when scientists learned how to preserve the male's

sperm by freezing it in liquid hydrogen. Since then, he said, they have

little by little learned how to understand when the female is ready to

conceive, a period of only a few days each year. The prospective mother

emits a distinctive sound when she is ready, he added, and her sexual organs

change color, turning red then white.

 

If conception occurs, baby pandas remain in gestation for 160 days, after

which one or two cubs are born.