After a decade of steady population growth, giant pandas were downgraded from “endangered” status to “vulnerable” last year. But a new study in the journal Nature Ecology & Evolution suggests those gains may be short lived if more attention isn't paid to the animal's habitat, which is becoming increasingly fragmented.
As Ben Guarino at The Washington Post reports, researchers examined satellite images from 1976, 1988, 2001 and 2013, in search of suitable panda habitat. According to the analysis, overall the creatures' habitat decreased by 4.9 percent between 1976 and 2001, recovering only 0.4 percent by 2013.
But total habitat doesn't give the whole story.
Road building and road improvements have fragmented the bamboo forests where the fuzzy creatures prefer to spend their time. In 1976 there were 400 of these forest patches, by 2013 that number had increased to 55. And the average size of the forest patches is shrinking, decreasing by 24 percent between 1976 and 2001, only rebounding by 1.8 percent since then.
“There have been some good changes and some bad changes,” study author Stuart Pimm, of Duke University tells Guarino. “The panda habitat has been diced and sliced into smaller and smaller pieces.”
As John Barker, head of the World Wildlife Fund’s Asia programs tells Helen Briggs at the BBC, the building of busy roads through the mountains, which the bears avoid, and other development at the forest’s edge hems in the animals, creating small isolated populations that cannot interbreed. Accoridng to the WWF, wild pandas are currently limited to 20 islolated patches of bamboo forest in six mountain ranges. Historically, they lived in a wide swathe of Gansu, Sichuan and Shaanxi province in the southeast of China.
China has taken big steps toward preserving the animals, including establishing a network of 67 panda preserves and captive breeding programs. In 1999, China also shuttered logging operations in panda habitat, leading to the recent uptick in bamboo forests.
But linking those preserves and remaining habitat together is necessary to keep the wild population healthy and to sustain recent population gains. “Creating wildlife-friendly areas and corridors that link these fragmented populations is essential, including finding ways for pandas to move over or under roads,” Barker says. “If the giant panda is to truly thrive in the wild we need to boost efforts to maintain their habitats, ensure that they are connected and safeguard the future for pandas by making sure that developments are designed responsibly with the lowest possible environment impact.”
The paper suggests several measures to help keep the panda from slipping back into endangered status. First, the authors propose setting “ecological red lines” or forest boundaries that strictly prohibit habitat destruction or exploitation. They also suggest expanding panda reserves to include habitat in the “red line” areas and the establishment of habitat corridors to connect panda populations, including the use of road tunnels wherever possible. The authors also recommend that people living in panda habitat should be encouraged to move to other parts of the countryside to limit disturbances to the bears.
It's a tough road ahead, but perhaps if we can preserve more of their habitat the gentle giants can start to thrive.