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Photo of Don Lindburg Don Lindburg
Zoos as Arks

Don Lindburg is Panda Team Leader at the Center for Reproduction of Endangered Species (CRES), part of the Zoological Society of San Diego devoted to conserving endangered animals. Read Tom's answers to viewers' questions to learn more about the giant panda and CRES's efforts to preserve this critically endangered species.

q I was wondering if someday would you consider taking the DNA sequence from the Giant Panda and cloning the panda to be an option in preserving this species?

A The most important aspect of conserving any endangered species is protecting wild animals in their native habitat. There are some species who were eradicated from the wild, and have only been saved from extinction because of their existence in zoos. The Zoological Society of San Diego has been able to help return a few of these species, the California condor, the Arabian oryx and Nubian ibex to the wild, but it is a long, difficult process. We are focusing most of our attention at saving the wild, rather than on technological fixes.

q How long have you worked with pandas? Have you ever gotten bitten or hurt by one?

A The San Diego Zoo received the giant panda pair, Bai Yun and Shi Shi in September 1996. Until then, most of the work we were doing was with pandas in the wild, observing them, studying them from a distance. It is important to remember that pandas are bears, and like other bears, can be very dangerous. We have never had anyone here injured, but it is definitely something to be aware of.

q How old can panda bear live to be? What do Pandas spend most of their time doing? What is their favorite food?

A It is estimated that pandas can live to be over thirty years old, in captivity. In the wild, their lifespan is probably much shorter. Pandas spend most of their time eating, looking for food and sleeping. Their favorite food is bamboo.

q What are some of the problems that face pandas living in captivity?

A There are very few giant pandas in captivity, and most of these are in China. Many of these are animals that have been injured in the wild and are not considered releasable. Each animal of course has its own story and its own unique needs. Pandas in the wild are faced with a number of challenges, including finding food, a place to live and a mate in an ever-shrinking bamboo forest.

q Is a re-release program planned in the future of Pandas? If so, where will they be released and when? Will a radio tracking system be implemented?

A In September, 1997, the Chinese government convened an international meeting on re-release of captive-born pandas to the wild. The conclusion of that meeting was that although re-release is an important goal, this is not the time to pursue that kind of program. First, it is necessary to perform a complete census of the existing population in order to find out how many pandas are left in the wild, and exactly where they are located. The second requirement is to find places where there is plenty of food and the released pandas would be safe from poachers. It may be another 10 years before these goals are achieved. When pandas are released, they will definitely be followed with radio tracking to make sure they can be located and determined to be doing OK.

q Now that you have found the program you've been running really has not made that much difference to the monkeys' eventual survival, are you going to disband it and just teach them in the real environment in Brazil?

A You are correct that allowing the tamarins to range freely in forests on the Zoo grounds does not confer an increase in their post-reintroduction survival. But it does have a powerful educational impact on our 2,500,000 annual visitors, and we can use the tamarins to present lots of good information on biology and conservation. Thus we will continue to have free-ranging exhibits in about six zoos in the United States. What's the nearest zoo to you to have a free-ranging golden lion tamarin exhibit?

q What is going to happen to that panda that had the messed up nose? Will he ever be able to mate?

A The panda with the messed up nose is our male Shi Shi. We now believe, after two seasons of trying, that it is unlikely he will ever mate. That is why we artificially inseminated our female. Bai Yun, the female, tried very hard for many days to get him interested in mating with her. We do not know the reason why he is disinterested, but think it might be his advanced age (about 20 years) more than a nose problem that accounts for his reluctance.

q When I grow up, I want to help endangered animals. But how?

A I am very pleased to learn that you are interested in helping endangered animals, and there are many ways to do so. The reason so many animals are endangered is that their habitat is disappearing or they are poached for their skins or other body parts. One way to help is to work through our political system to help preserve a place for endangered animals. Others have made this issue a very personal one, and have chosen to voluntarily limit the number of children they will have in order to slow the growth of the human population. Still others have gotten directly involved by studying the animals both in the wild and in captivity in order to increase understanding of their needs. You do not have to wait until you grow up in order to help. In my city of San Diego, many school children collect aluminum cans for a program called "Cans for Critters", and donate the funds to an organization involved with saving endangered animals or plants. Concerned children like yourself can make a huge difference in making the planet a friendlier place for animals.

q I read about the recent artificial insemination of Bai Yun. Is the San Diego Zoo the first to try this? Are you optimistic about the results? I wish you good luck!

A Artificial insemination has been tried before, with mixed results. A zoo in Madrid, Spain, tried it once and succeeded. A zoo in Tokyo, Japan, has had three infants born from this procedure. Other zoos have tried and failed. In China, artificial insemination is used frequently, but we do not know the success rate.

The most important factor in being successful is the timing, that is, inseminating whenever the female releases her egg for fertilization. Our monitoring of the female's hormones indicates that we timed the procedure perfectly. We estimate that 500 million sperm were placed in her uterus. We are reasonably hopeful the procedure will succeed, but since it is the first time for us to try it, we will not be surprised if there is no baby next August.

q How do scientists decide when it's time to classify an animal as endangered? And when or how do they decide to take it off the endangered list?

A Decisions to classify an animal as endangered are based on several factors, including the actual numbers surviving in the wild, whether or not the wild population is increasing or declining, pressures on the wild population such as poaching or ongoing loss of habitat through logging or farming, the position of governments on conservation in the country where the animal lives, the birth rate of the population and the time required to reach adulthood, etc. In some cases there is no single factor that determines the decision, although if a species has only a few hundred or maybe even a few thousand left, it is clear that the other factors are less relevant except as factors to be considered in trying to save the species from going extinct.

Taking an animal off the endangered list requires as a minimum that its numbers are either stable at a healthy level or growing, and enough protected habitat is available to the species as a place to live.

q Hi, I saw your show and I have seen lots of shows on pandas. I am wondering if the panda bear ever has more than one or two cubs.

A Since the first captive birth of a panda cub at a zoo in China in 1963, slightly more than half of all litters (52%) have been twins. There are no known cases of a female having more than two cubs. An interesting aspect of giant panda twinning is that the mother will normally raise only one. This means that, in the wild, a second cub in a litter of twins does not survive.

q Is the panda really a member of the bear family? I have also read it's related to the raccoon. It's great to be able to ask an expert to answer this for me!

A There are actually three possibilities: pandas are closely related to bears, pandas are closely related to raccoons, or pandas are in a family of their own. The answers are still being very much debated. At one time it was thought the analysis of blood samples (molecular genetics) would resolve this question, but different geneticists have obtained different results. Dr. George Schaller, who studied pandas in the wild, thinks pandas are in a family by themselves, whereas Dr. Steven O'Brien, a molecular geneticist, is firmly convinced they are bears. More study is required before there is an answer that will satisfy everyone.

q Are there other programs similar to yours at the San Diego Zoo going on around the world to try to breed the panda in captivity? I am curious what programs, if any, the Chinese have to help this species.

A Yes, there are other countries outside of China that are trying to breed pandas. At present, these are limited to zoos in Mexico City, Berlin, and Tokyo. None of these zoos use science to direct their breeding program to the extent we do in San Diego.

China also has captive breeding programs in several of its zoos, and at two specially built research stations. Although most of the panda births have occurred in China, the birth rate is still quite low and many of the cubs do not survive. The institutions in China have asked zoos such as San Diego to assist them in improving the results of their breeding programs. All are agreed that the highest priority should be on assisting with the preservation of the wild population, however.

q McKelvie Middle School, Bedford, NH, students will be conducting the activity "If I ran the zoo." We are in need of information regarding animals, and their recommended habitat size. We have searched the internet addresses with no luck on this data. Please address.

A Unfortunately there is very little concrete data on habitat sizes for various species. The USDA has basic, general requirements however, most zoos go beyond this in their effort to maintain animals in captivity. The best resource for this would be the American Zoological Association (


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