The global demand for rubber tyres is threatening protected forests in Southeast Asia, according to a study.
Tropical forests are being cleared for rubber plantations, putting endangered birds, bats and primates at risk, say UK researchers.
By 2024, up to 8.5 million hectares of new rubber plantations will be needed to meet demand, they report in Conservation Letters.
This could have a "catastrophic" impact on wildlife, they warn.
Species such as the endangered white-shouldered ibis, yellow-cheeked crested gibbon and clouded leopard could lose precious habitat, said the team led by Eleanor Warren-Thomas, from the School of Environmental Sciences at the University of East Anglia.
"The tyre industry consumes 70% of all natural rubber grown, and rising demand for vehicle and aeroplane tyres is behind the recent expansion of plantations. But the impact of this is a loss of tropical biodiversity," she said.
"We predict that between 4.3 and 8.5 million hectares of new plantations will be required to meet projected demand by 2024. This will threaten significant areas of Asian forest, including many protected areas."
Eight-point-five million hectares is about the size of the land area of Austria.
Biodiversity concern
Rubber is the most rapidly expanding tree crop within mainland Southeast Asia.
Concern has been growing among conservationists that switching land use to rubber cultivation can harm soil, water and biodiversity.