China's Giant Panda

موضوع: China's Giant Panda الأربعاء يناير 19, 2011 10:31 pm

[left]The giant panda is known and loved all over the world, but much of its way of life still remains a mystery. Before its survival can be guaranteed, it is vital that we learn more about it. Reduced to a few scattered populations in the mountain forests of central China, the giant panda is now one of the rarest of all mammals. Determined conservation efforts are underway which may yet secure the future of this popular but endangered species.
The giant panda once inhabited forests throughout southern and central China. Today it is restricted to just a few isolated pockets of high altitude forest in Sichuan and adjacent provinces to the south of the central Qinling Mountains. Although no one knows for sure, most authorities agree that there are only between 500 and 1,000 giant pandas left in the wild.

Built like a bear, some aspects of the giant panda's anatomy suggest, instead, that it is a sort of overgrown racoon. Scientists cannot agree to which group of animals it belongs. While technically it is a flesh eater, it has all but abandoned predatory habits and become a placid vegetarian. It will eat meat if it gets the chance, however, particularly in the form of insects, rodents and carrion.
In its native forests in the mountains of central China, it feeds almost exclusively on the leaves and young stems of bamboo. As it is very tough on panda's teeth, the carnassial (meat slicing) teeth wear to become flattened, broad molars for pulping plant fibre. Bamboo grows all over the cool, damp mountain forests. Each giant panda occupies a range of 2 square kilometres and rarely travels farther afield.
Solitary and secretive, it is most active at dawn and dusk, when it is difficult to spot in the dappled green twilight of the bamboo forest. Scientists studying the panda in the wild may wait weeks between sightings, and our knowledge of its habits is correspondingly scanty.

The main reason for the giant panda's decline has been the destruction of its habitat. All over southern and eastern China, forests have been cut down to make way for settlement and agricultural needs, driving the panda back to the most rugged, inaccessible areas. It is fairly secure there as local people treat it with reverence. Poaching continues, however, and the main panda habitats have been declared nature reserves.
The real problem for the giant panda today is one of isolation. Pandas living in adjacent reserves are unable to interbreed since areas of valley grazing and cultivation separate the 13 mountain forest reserves. The adult population in each of the reserves consists of only a few dozen animals at most, so each group inevitably suffers from in-breeding. Giant pandas are extremely reluctant breeders, with a poor rate of successfully reared cubs. A female raises only one cub, if she has twins, she concentrates on one, abandoning the other to starve.

Ever since the giant panda was first described by a western naturalist in 1869, it has facinated people all over the world because it looks like the ultimate cuddly toy. The Chinese government has given away giant pandas as gifts to diplomats and foreign heads of state on visits to China. Air-freighted home to be installed in zoos, these animals have spent their lives in solitary confinement. There are estimated to be about 100 pandas kept in zoos around the world.

The prestige attached to panda ownership has made the various national zoos very reluctant to part with their prizes, so the dozen or so pandas outside China remain scattered around the world as pairs or single animals. As a result, there have been very few breeding successes.

Some co-operation does exist, however. In 1988, the London Zoo sent its male panda to Mexico City to be paired with a female there. Many captive pandas have psychological problems that stop them breeding. One female panda at London Zoo became so accustomed to human company that she was unable to accept the advances of a visiting male, while a male at Washington Zoo was simply ignorant of the correct mating procedure.

China is proud of its giant pandas and has set up a number of research centres in order to watch and study it in the wild. By finding out exactly how it lives and what it likes, it can be encouraged to breed and prosper. Researchers are hampered by the terrain, however, panda country is inaccessible, with steep mountains divided by deep, densely wooded ravines, and the pandas themselves do not take kindly to being watched. Research teams have developed a variety of techniques for getting around this problem. One of the most basic is to collect panda droppings and analyse them. Since much of the bamboo passes straight through the panda, it is possible to find out which type of bamboo the panda prefers, how old the plant has to be and which part the panda eats.

Rather more sophisticated is the use of radio-tracking equipment. This involves capturing a panda, equipping it with a miniature radio transmitter on a collar and releasing it. The transmitter provides information about the animal's position and pulse rate, so a researcher can monitor its movements through the forest and deduce from its pulse rate whether it is sleeping, eating or even ready to mate.

Bamboo flowers and withers in cycles, so huge areas die out completely every so often. In 1975, great tracts of bamboo in the provinces of Sichuan and Gansu were laid waste, and 138 giant pandas were known to have starved to death as a result. There is nowhere for the pandas to go to find food and the problem is made worse because each panda needs a vast amount of bamboo to survive.

Bamboo is hard to digest and low in food value, yet the panda has retained a digestive system more suited to a diet of meat and fruit. Most of the bamboo passes straight through its gut, and so to take in enough to survive, the panda has to spend up to 12 hours a day eating.

The researchers have two main priorities. The first is to prevent a recurrence of the bamboo famine disaster of 1975 and the second is to improve the panda's breeding rate. In the first they have already faced a severe test, for in 1983 there was another widespread bamboo die-back. By setting up feeding stations and capturing and treating severely emaciated pandas, the special 'panda patrols' managed to reduce the death rate to just 14 animals this time.

More positively, there are plans to plant different varieties of bamboo alongside each other in the panda habitats, in order to ensure that there is always some bamboo to eat. Another idea is to establish bamboo 'corridors' linking the various reserves. This would alow pandas to migrate if necessary, and might even encourage some interbreeding between populations.

Breeding captive pandas by natural means alone could never solve the problem, so some of the captive-breeding stations are using artificial insemination. One major difficulty here is detecting when the female is receptive. This is critical since she seems to be on heat for only three days a year, and it is easy to miss.

By regular testing for hormone levels in the urine, however, a vet can determine the ideal moment to introduce the male's sperm, which is kept frozen ready for use.
China's Giant Panda Panda1

موضوع: رد: China's Giant Panda الخميس يناير 20, 2011 12:41 am