By Judith Burns
Science and environment reporter, BBC News
Scientists attached collars to the bats to track their movements by satellite
Scientists are urging the government of Malaysia to ban the hunting of the world's largest fruit bat.
Researchers say the large flying fox will be wiped out on the Malaysian peninsula if the current unsustainable level of hunting continues.
Writing in the Journal of Applied Ecology they say around 22,000 of the animals are legally hunted each year and more killed illegally.
They say the species could be extinct there by as early as 2015.
Flying foxes can have a wingspan of up to 1.5m and are crucial for the rainforest ecosystems in this part of Asia.
Lead author, Dr Jonathan Epstein of Wildlife Trust, told BBC News: "They eat fruit and nectar and in doing so they drop seeds around and pollinate trees. So they are critical to the propagation of rainforest plants."
The most optimistic estimates put the population of flying foxes in peninsular Malaysia at 500,000.
Shooting at dusk
The animals are hunted for food, medicine and sport. Shooting takes place at dusk as the bats set out to forage overnight.
The researchers say their population models suggest that if current hunting rates continue it will take between six and 81 years for the species to be hunted to extinction.
The research team carried out abundance surveys and collected government data on hunting licences.
The scientists used a computer model to predict the fate of the species according to varying rates of kill and a range of current population estimates.
This was the first time satellite telemetry has been used to track bats in Asia. The method is often used to track birds but is more rarely used to study mammals.
The researchers trapped individual bats and fastened collars round their necks before releasing them.
Each collar sent a satellite signal which allowed the scientists to track the animal by computer.
The team found that individual animals travelled up to 60km a night in search of food.
Protected in Thailand
Flying foxes, or Pteropus vampyrus, are protected in neighbouring Thailand but hunting is allowed in Malaysia and parts of Indonesia.
Dr Epstein said: "We think this shows there is a need for co-ordinated protection management along the countries where these bats live. It's clear now that they are not just Malaysian bats but they share time between Sumatra, Thailand and Malaysia."
The Malaysian government wildlife departments were partners in the study and are looking at reviewing the hunting laws in the light of the results.
Dr Epstein and his colleagues have recommended at least a temporary ban on hunting to allow the population to recover and to give time for a more comprehensive assessment of the threats to their survival in peninsular Malaysia.