Competition with native wildlife could deter efforts to boost populations of the famous black-and-white bear in its native habitat.
SEPTEMBER 1, 2021
HONG KONG The giant panda, China’s national animal, is a global symbol of cuteness. But the black-and-white bears have long suffered for their irresistible qualities—poached for their pelts, smuggled out of the country as cubs to the U.S. and Japan, and speculated on like a tradeable stock by zoo collectors.
By the 1980s, their numbers in the wild had fallen to just over a thousand. Extinction loomed.
But this summer, pandas also became a global symbol of conservation success. Chinese officials announced that the animals—whose wild population has almost doubled after 30 years of government-led recovery efforts—are no longer endangered.
In 2016, the International Union for Conservation of Nature had already downlisted the giant panda from endangered to vulnerable, citing a steadily increasing population and expanded habitat. But some Chinese scientists and officials rejected that assessment, saying it was premature and could undermine panda protection efforts.
Much has been achieved since 2016. China has designated a new Giant Panda National Park, which covers 70 percent of the animals’ existing habitat, mainly in Sichuan Province. And the number of pandas in captive-breeding programs around the world has nearly doubled, to 633. That’s more than twice as many pandas scientists say are needed to preserve genetic diversity, essential for the survival of the species.
Meanwhile, a study about the effects of climate change on bamboo, which makes up 99 percent of pandas’ diet, shows that their tolerance—and that of bamboo—to variations in temperature and rainfall is much higher than previously thought. (Read how the new panda park will be three times the size of Yellowstone.)
“In reality, today’s increase was something no one was certain would happen 20 years ago. Now, the panda is a very successful case,” says Fang Wang, a conservation biologist in the School of Life Sciences, at Fudan University, in Shanghai.
Successful within limits, though, because panda recovery isn’t assured, experts warn. Widespread deforestation and habitat fragmentation restrict pandas in the wild to less than one percent of their historic range. And new threats loom.
Natural conflicts
China’s setting aside of more land in nature reserves to help pandas recover has also benefited Sichuan takins, shaggy, pale-brown ungulates resembling a cross between a cow and a mountain goat that can weigh up to 800 pounds. Their numbers in Tangjiahe National Nature Reserve, an important panda refuge, nearly tripled from 500 in 1986 to more than 1,300 in 2015. (Male takins can be dangerous, particularly during rutting season. During a nine-year period in the Qinling Mountains, they killed 22 people and injured 184.)
“We’ve observed how takin activity clearly influences vegetation growth,” says Diao Kunpeng, founder of the Sichuan-based nonprofit Qingye Ecology, which works to help manage and carry out research on nature reserves.
Takins strip bark from trees for food, exposing them to deadly fungal infections and insects. As a result, the composition of the forest changes—fewer large trees, more shrubby undergrowth. "But pandas like bamboo forests with large trees” that serve as maternity dens for raising their young, Diao says.
Pandas mark trees with a waxy substance secreted from glands beneath their tails as a way to communicate and find mates. But when takins rub against trees to relieve itchiness, they can eliminate or diminish the scent marks.
Scientists don’t yet have conclusive data to show how forest changes affect wild pandas, but a long-term study in Tangjiahe should provide more answers, Diao says.
According to Wang, northern Chinese boars may be even more troublesome for pandas. Both are protected in China. No official estimate of boar numbers exists, but anecdotally it appears that they outnumber takins, their range is larger, and their impact on the environment far more pronounced, he says.
Each spring, young bamboo shoots provide a valuable source of protein and nutrients for pandas, particularly for pregnant or lactating mothers. But boars also like to eat young shoots, and research shows that pandas avoid foraging in areas inhabited by boars. Meanwhile, panda numbers increased in neighboring areas with few boars.
Furthermore, boars carry diseases such as canine distemper and swine fever, which can jump to other species. “It’s certain that these viruses will infect pandas,” Wang says.
And with their rooting, boars also damage villagers’ crops, which Wang fears could reduce support for wildlife conservation efforts in areas where pandas live.
Giant pandas have very few natural predators, and in the past, animals such as snow leopards, a type of wild dog called a dhole, and wolves kept takin and boar numbers in check. But these apex predators have nearly disappeared, according to a 2020 study co-authored by William McShea, a wildlife ecologist at the Smithsonian Conservation Biology Institute, in Front Royal, Virginia. Most died out because of poaching and habitat loss, says McShea, who has worked in China for more than 20 years and argues for “putting these carnivores back.”
Wildlife officials lack sufficient data on either takins or boars to develop management plans that would balance their numbers and needs with those of pandas, according to Wang.
The Sichuan Forestry and Grassland Administration, the agency responsible for overseeing wildlife and habitat conservation, did not respond to National Geographic’s request for comment.
‘The positive future of the panda’
During much of the 20th-century, panda pelts sold on the international black market fetched huge sums—up to $100,000. In his 1994 book The Last Panda, naturalist George Schaller described the panda as a species beset by poaching, habitat loss, and bad management. At the time, he predicted that “poachers would eliminate the panda long before inbreeding could become a problem.”
Today, poaching is rare, and logging has been all-but eliminated inside and outside reserves. Schaller, now in his late 80s, says he’s much more optimistic. If he were to write a new book, he says, “it’d have to be something about the positive future of the panda.”
A dedicated network of wildlife rangers has helped stem pandas’ decline—in Sichuan Province, home to most wild pandas, at least 4,000 rangers patrol the 166 nature reserves. “Rangers act like a buffer between the law and traditional practices,” Wang says.
They also assist conservationists and biologists by collecting vital information about the animals. Rangers usually live inside the reserves, trekking up to weeks at a time through mountainous bamboo forests to maintain camera traps and record wildlife behavior. Data they gather is used to determine China’s official wild panda count—the next official survey will be done in 2022—and inform conservation research and strategies.
One measure Chinese conservationists have adopted is to breed and raise pandas in captivity with the aim of releasing them into reserves to bolster wild populations.
Panda reintroduction is controversial because it’s expensive and time-consuming to raise pandas in captivity.
The effort has had mixed success. So far, 14 pandas have been released, 12 of them captive-bred. Of those, nine have survived. The two others were wild pandas that had been rescued and kept in captivity. The only released panda ever confirmed to successfully breed in the wild was one of the wild rescues. (Read more about pandas being reintroduced into the wild.)
In late 2019, the China Conservation and Research Center for Giant Pandas announced a plan to release three pandas in Jiangxi Province, where the animals have been extinct for at least 10,000 years.
This would have been the first release of captive pandas outside Sichuan Province had the plan not fizzled in mid-2020 amid fierce debate among Chinese researchers and officials over the efficacy of reintroducing pandas. (Check out three places to see giant pandas in the wild.)
“Within Chinese expert communities and even inside the breeding program team, there are very strong differing opinions,” Wang says. “So in regards to releasing pandas, there is no complete plan.”
Wang hopes a decision will be made to release more pandas in a methodical, targeted way, to boost small regional populations and to connect wildlife corridors so the animals can move about freely in areas with good habitat.
“No matter what, we don’t need 600 captive pandas,” Wang says. “Perhaps only after a certain amount of failure will we be able to release pandas better and improve the lives of wild pandas.”
The breeding program “isn’t going to change the world,” McShea says. “They’d be much better off creating reserves that produce abundant pandas and translocating those pandas."
(Sources: National Geographic)
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