African Lions have seen a sharp decline over the past century. (Charles Rex Arbogast/AP)

An expedition into a remote national park in Ethiopia has revealed a previously unknown population of African lions, suggesting that the species — which is categorized as "vulnerable" — may be more widespread than conservationists had hoped.

The Born Free Foundation announced the existence of the lions – confirmed with images taken by motion-activated cameras — in a news release Monday. Because the lions were spotted in Alatish National Park, which borders the Sudanese Dinder National Park, the researchers involved with the discovery hope that the population spans both countries. Altogether, the two parks could hold an estimated 200 lions.

An image of one of the newly discovered lions.(Born Free Foundation)
An image of one of the newly discovered lions. (Born Free Foundation)

That might not sound like a lot, but there are only an estimated 20,000 lions on the entire continent, down from 450,000 less than a century ago. Disease, habitat loss and other hardships could cause those numbers to drop even more in the future.

“During my professional career I have had to revise the lion distribution map many times,” lead researcher Hans Bauer of the Wildlife Conservation Research Unit told New Scientist. “I have deleted one population after the other. This is the first and probably the last time that I’m putting a new one up there.”

The find might be even more exciting: These lions could be members of a sub-species with only 900 living individuals. Now that they've been spotted, conservationists can work with Ethiopian and Sudanese governments to keep the national park population from dwindling.

"We need to do all we can to protect these animals and the ecosystem on which they depend, along with all the other remaining lions across Africa, so we can reverse the declines and secure their future," Born Free’s chief executive Adam M. Roberts said in a statement.

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