Although giant pandas have been removed from the endangered list, panda habitats are much smaller today than when the animals were listed as endangered in 1988, new research shows.
- Conservation areas have increased, but are more fragmented by roads, infrastructure
- Remote sensing offers sample method in inaccessible terrain
- Researchers hope future urbanisation may reduce habitat pressure
The panda's conservation status was downgraded from endangered to the lesser "vulnerable" on the International Union for Conservation of Nature (IUCN) Red List in 2016.
But researchers say in an article published today in the journal Nature Ecology & Evolution that panda habitat has become smaller and more fragmented due to increased infrastructure building in vital areas used for food and migration by pandas.
Study co-author Stuart Pimm from Duke University in North Carolina said despite a lot of good work from China in creating new panda conservation areas, tourism and development were putting increasing pressure on the species.
"The problem is they're building a huge amount of infrastructure. There's a massive program of building roads and bridges and tunnels, and that's good, but it means that the number of isolated habitats has increased quite dramatically since the 1970s," Professor Pimm said.
"Effective panda conservation is going to need us to try and connect some of these isolated areas with corridors."
He said panda scats have been found on green bridges that have been built across highways, suggesting the animals will use these routes when they are available.
Professor Pimm was part of an 11-person team of mostly Chinese scientists who compared a series of satellite images of the pandas' existing habitat between 1976 and 2013.
According to the data, overall habitat area decreased by 1.7 per cent between 1988 and 2013 and the average size of continuous habitat decreased by more than 13 per cent in the same period.
Currently, pandas are distributed in a series of 30 isolated patches in the tectonically active mountain region of central China, with 18 of those patches having 10 animals or less.
This is despite the creation of 67 reserves by 2013, and billions of dollars being spent by the Chinese government on incentives and conservation programs.
Habitat loss backs up 'father of pandas' criticism
The study timeframe included four periods in which China carried out national panda surveys.
Between the second and fourth surveys panda numbers appeared to increase, which led to the downgrading of the animals from "endangered" to "vulnerable".
When pandas were taken off the IUCN endangered species list, the wild population was estimated to be between 1,864 and 2,060 animals.
Although Professor Pimm did not wish to dispute the panda-population estimates produced in those surveys, he said that the new remote sensing technology used in this study offers a more consistent way to measure changes in panda habitat over time.
"Everybody thinks that there has been an increase [in numbers], but pandas are really hard to count," he said.
"They're in very tough terrain, very high mountains, they live in forests, in bamboo thickets.
"What people count are the panda droppings. People measure the bamboo droppings and if the droppings are different in size they think it's a different panda.
"The IUCN rely very largely on those counts."
When the panda's status was downgraded in 2016, critics including the China Conservation and Research Centre's Zhang Hemin, known locally as the "father of pandas", said it was too soon.
"If the conservation status is downgraded, protection work might slacken off and both the panda population and their habitat are more likely to suffer irreversible loss," Mr Hemin said.
Given current levels of conservation, and the implementation of China's urbanisation plan, the researchers said it's likely some of the pressures on pandas and their habitats would decrease.
"Both the total and agricultural population will likely decrease within the panda's range," the researchers wrote.
But, they said, other measures were needed to ensure the panda's long-term survival and prevent it from being upgraded to "endangered" again.
These measures included the establishment of mandatory conservation areas linked by habitat corridors that are transected preferably by road tunnels not traditional roads.
Panda conservation areas should also take into consideration other endangered species and aspects of the ecosystem such as water supply.
"Finally, the new establishment of panda national parks should coordinate and balance conservation with tourism," they said.
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