The National Zoo's 9-month-old baby gorilla is recovering from a broken leg, the zoo said Friday.

The cause of the injury is unknown, but the zoo said "rambunctious" little Moke is "a bit of a daredevil." It's possible that he landed the wrong way during a jump, the zoo said.

The break was discovered after keepers noticed Moke wasn't putting weight on his left leg, although he was still nursing, eating, walking and climbing.

An exam revealed he had a broken femur, although it doesn't appear to be a bad break.

As a result, the zoo is going to try to let the injury heal on its own. There was a risk that Moke or his troop wouldn't tolerate a cast on his leg. Another option would have been to surgically implant a plate in his leg, something vets also decided against.

"Moke is resting and recovering with his parents, Calaya and Baraka, under the close watch of the animal care team," the zoo said on its website.

The zoo said he's not showing signs of discomfort. Moke is likely to regain about 80 percent stability within a month, and the break should fully heal within a couple of months, the zoo said.

The primate team will monitor Moke's behavior and contact vets if they have any concerns. The zoo said keepers have a "positive and trusting relationship" with Calaya, but the gorillas "get suspicious" when vets enter the building.