blog post and graphics by: yunyi cui
On the morning of August 21, 2020, Mei, the female giant panda who has been living in the Washington National Zoo for the last twenty years of her long life, defied all biological odds and gave birth to a tiny panda cub. At 22 years old, Mei’s chances of getting pregnant were less than one percent, making the birth of her baby a miracle in the zoological world.
Pandas are notoriously bad breeders. A combination of factors are responsible for this phenomenon, including an incredibly short estrous cycle, which lasts only 24-46 hours, and behavioural incompatibility (1). As a result, the low birth rate of pandas is one of the contributing factors to their status as a ‘vulnerable’ species, with a population count of less than 2000 in the wild (2). With the challenge of reduced amounts of zoo staff during the pandemic, the hopes of panda reproduction this year seemed to be slim to none, making Mei’s birth extra special.
Mei’s baby cub is the product of captive breeding, which is a process where humans breed rare species in a controlled environment such as a zoo or a conservation center (3). Captive breeding programs exist to restore the population level of endangered species and help to maintain biodiversity. Although a small number of captive pandas mate naturally, the use of assisted reproduction techniques, such as artificial insemination, is much more viable in the captive breeding setting. Artificial insemination involves collecting the sperm of a male and artificially implementing it into the body of the female. The first successful case of artificial insemination in pandas occurred at the Beijing Zoo in Beijing Zoo in 1978 (4).
Over the years, the panda has become an icon in the world of animal conservation. From being the gold star attractions to zoos around the globe to acting as the logos of international conservation organizations, pandas are undoubtedly world-wide famous. But is this symbol of conservation success really warranted? Several conservation experts have voiced their doubts on the matter, including University of Colorado ethologist Marc Bekoff (5).
According to many like Bekoff, the end goal of captive breeding programs should be to eventually reintegrate the animals into the wild. However, our records of panda reintegration thus far have been less than stellar. In 2007, scientists introduced 5-year old Xiang Xiang into the wilderness in Wolong, only to find out that he had fallen to his death after engaging in a fight with local males (6). Xiang Xiang is one of only two attempts at giant panda reintegration so far, making it appear as if little progress in this area has been made.
This incident brings up the interesting ethical question: Should humans be able to breed pandas in captivity despite possible drawbacks, such as losing their ability to survive in the world?
References
Giant Panda Estrus FAQs [Internet]. Smithsonian’s National Zoo. 2017 [cited 2021 Apr 3]. Available from: https://nationalzoo.si.edu/animals/giant-panda-estrus-faqs
Giant Panda | Species | WWF [Internet]. World Wildlife Fund. [cited 2021 Apr 3]. Available from: https://www.worldwildlife.org/species/giant-panda
Society NG. Captive Breeding and Species Survival [Internet]. National Geographic Society. 2010 [cited 2021 Apr 3]. Available from: http://www.nationalgeographic.org/activity/captive-breeding-species-survival/
Liu W. The test of giant panda artificial insemination. Chinese Science Report 1979; 9:415.
Is Breeding Pandas in Captivity Worth It? [Internet]. Science. 2013 [cited 2021 Apr 3]. Available from: https://www.nationalgeographic.com/science/article/130827-giant-panda-national-zoo-baby-breeding-animals-science
First Panda Freed Into Wild Found Dead [Internet]. Animals. 2007 [cited 2021 Apr 3]. Available from: https://www.nationalgeographic.com/animals/article/china-freed-panda-death-animals
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