In Africa, the circle of life is fraying: Simba and his pride are rapidly losing ground. New research shows that lions are quickly disappearing across Africa’s once-thriving savannahs due to human population growth and massive land use conversion.

Lions, a new Panthera report says, exist on less than 75 percent of their original habitat, which comprises an area larger than the United States. Over the past three decades, lion populations declined about 50 percent, to fewer than 35,000 individuals today.

To figure out how lions are doing in the field, the researchers used Google Earth’s high-res satellite images to examine savannah habitat across Africa. They analyzed human population density and labeled areas of existing suitable lion habitat. They found 67 isolated areas across Africa where the big cats may persist and found that just 15 of those areas might maintain lion populations of at least 500 individuals.

Following on the heels of this discovery, the U.S. Fish and Wildlife Service announced this week that African lions may deserve protected status under the Endangered Species Act. Figures show that lion hunts have increased recently, with Americans leading the race in importing lion trophies. If lions join the Endangered Species List, however, these trophies would no longer be allowed to enter the U.S., meaning many hunters may not have incentive to travel to Africa and take part in lion hunts. Scientific American sums up the state of the legislation:

The Fish and Wildlife Service is now soliciting public comments on the proposal to add African lions to the endangered species list (to comment, go to regulations.govand enter Docket No. FWS-R9-ES-2012-0025). After the 60-day comment window, the FWS will further review whether listing the cats is appropriate.

More from Smithsonian.com:

The Truth About Lions

Humans Steal Food From Lions