Habitat loss drives Sumatran tiger to verge of extinction

The destruction of vegetation is driving the Sumatran tiger to the brink of extinction, World Wildlife Fund (WWF) researchers say.

The Sumatran tiger, native to Indonesia, could be the fourth type of tiger to disappear from the wild thanks to deforestation and the loss of thick groundcover, also known
as understory cover, said Sunarto, a WWF tigert expert, who led the study, the first to investigate the use of both forests and plantation areas for tiger habitat.

Although tiger's prefer forest to plantation areas, the study found that the most important factor was that availability of thick ground-level vegetation which apparently serves as an environmental necessity for tiger habitat, regardless of location, the journal Public Library of Science ONE reported.

"As ambush hunters, tigers would find it hard to capture their prey without adequate understory cover," said Sunarto, who earned his doctorate at Virginia Tech and now is a tiger expert for the World Wildlife Fund-Indonesia (WWF-Indonesia).

"The lack of cover also leaves tigers vulnerable to persecution by humans, who generally perceive them as dangerous," added Sunarto. Within forest areas, tigers also strongly prefer sites that have low levels of human disturbance, according to a univeristy statement.

Estimates place the current wild tiger populations at as few as 3,200 tigers, including only about 400 Sumatran tigers, which are listed as critically endangered on the International Union for Conservation of Nature Red List of Threatened Species.

"These study results indicate that to thrive, tigers depend on the existence of large contiguous forest blocks," said study co-author Marcella Kelly, associate professor in Virginia Tech's department of fish and wildlife conservation and Sunarto's graduate advisor.

The Indonesian government has set aside many areas and national parks for the conservation of endangered species, but about 70 percent of tiger habitat in Sumatra, an island in western Indonesia, remains outside these protected areas.