About 10 years ago, when the Department of Environmental Affairs tackled the issue of canned lion hunting, the resultant legislation ruled that captive-bred lions had to be released into large areas for two years before they could be commercially hunted.

Johannesburg - More than two-thirds of the lions estimated to have lived on Africa's savannahs have disappeared in the last 50 years because their habitats are disappearing, according to a study published in the US.

The study, led by Duke University researchers and published in the journal “Biodiversity and Conservation”, estimates the number of lions now living on the savannahs to be as low as 32,000, down from nearly 100,000 in 1960.

Lion populations in West Africa have experienced the greatest declines, according to the report, published in December, because of massive land-use change and deforestation, driven by rapid human population growth.

“Only 25 percent remains of an ecosystem that once was a third larger than the continental United States,” said Stuart Pimm, Doris Duke Professor of Conservation Ecology at Duke’s Nicholas School of the Environment.

Researchers coupled high-resolution satellite imagery from Google Earth with human population density data and estimates of local lion populations.

They found only 67 isolated areas of savannah across the continent with suitably low human impact. Ten spots deemed to be “strongholds” for lion survival were in national parks. About 24,000 lions were in strongholds.

Of the estimated 32,000 to 35,000 lions, more than 5000 are in small, isolated populations, putting their survival in doubt, according to the research.

To arrive at the estimate of between 32,000 and 35,000 lions, the research team worked with groups which including local “user communities” such as hunting organisations.

Previous estimates had placed the number of lions remaining on the savannah at between 20,000 and 40,000.

African savannahs are defined as areas that receive between approximately 11 to 59 inches of rain annually.

According to the report, only nine countries had at least 1000 “free ranging” lions: Central African Republic, Kenya, Tanzania, Mozambique, Zambia, Zimbabwe, South Africa, Botswana, and possibly Angola.

South Africa's Kruger National Park had about 1700 lions.

Tanzania alone had over 40 percent of Africa’s lions. - Sapa