Africa’s savannahs, and the lions that have found their home there, are disappearing at an alarming rate, plummeting two thirds over the past 50 years, a study found Tuesday.
Using new satellite data, Duke University researchers estimated that as few as 32,000 lions now live on the continent’s savannahs, down from nearly 100,000 in 1960.
The declines were particularly dire in West Africa, where human populations have doubled over the past three decades, according to the study published in the journal Biodiversity and Conservation. It said fewer than 500 lions remain in the region.
“Only 25 percent remains of an ecosystem that once was a third larger than the continental United States,” said Stuart Pimm of Duke’s Nicholas School of the Environment.
He blamed the decline on massive land-use change and deforestation driven by rapid human population growth encroaching on the big cats’ habitats.
Pimm and his colleagues mapped areas still favorable for lions’ survival by using high-resolution satellite imagery from Google Earth, along with human population density data and estimates of lion populations.
They found only 67 isolated stretches of savannah, defined as areas that receive between approximately 11 to 59 inches (28 to 150 centimeters) of rain annually, across the continent that had low enough human impacts and densities.
And only 10 of those areas were considered “strongholds” where lions had an excellent chance of surviving, many of them located within national parks.
The National Geographic’s Big Cats Initiative funded the study.