Asheboro, NC - In a rare event for an American zoo, a second baby gorilla has been born in less than a month at the North Carolina Zoo.

Olympia, a 16-year-old female, gave birth around 7 p.m. Friday to a four-pound baby. The sex of the infant, which went on exhibit with its mother Saturday morning, has not yet been determined and a name has not been selected.

Zookeepers saw signs that Olympia was going into labor when the gorillas were brought off exhibit around 5 p.m. Friday. The infant was born in the gorilla holding quarters about two hours later and seems to be in good health, according to keepers.

On August 4, the N.C. Zoo saw its first successful gorilla birth in 23 years when Jumani, age 12, gave birth to a healthy male baby named "Bomassa" by keepers. Jamani came to the N.C. Zoo from the San Diego Zoo in January 2010. Olympia arrived in Asheboro in March 2009 from Zoo Atlanta and was named for the Summer Olympics held in Atlanta in 1996.

The father of both infants is "Nkosi," a 19-year-old male who arrived at the N.C. Zoo from the Columbus Zoo in March 2008. All three gorillas were brought to the N.C. Zoo and recommended for breeding as part of the Gorilla Species Survival Plan (SSP) of the Association of Zoos and Aquariums (AZA). The SSPs have been developed by AZA to improve the care and breeding of animals in captivity and currently includes plans for more than 500 species.

Although this is Olympia's first baby, she seems to be providing excellent care for the newborn, keepers reported. Olympia's delivery marks only the third gorilla born at the N.C. Zoo. The first was a male named "Kwanza," born in March 1989. Kwanza was transferred in1998 to Chicago's Lincoln Park Zoo as part of the Gorilla SSP and has since fathered two offspring of his own.

Any gorilla birth is a significant accomplishment, but two in such a short period is very unusual, according to N.C. Zoo Keeper Chris Goldson who supervises the gorilla section. Currently there are only about 350 gorillas in 52 AZA-accredited zoos with just four successful births out of eight pregnancies recorded during 2011 and early 2012.

Keepers had originally predicted Olympia would deliver in October. But with a gestation period of eight-and-a-half months it is difficult to determine the delivery date for gorillas because keepers could not be certain of the conception date, Goldston explained.

The zoo is an agency of the N.C. Department of Environment and Natural Resources, Dee Freeman, Secretary; Beverly E. Perdue, Governor.