COLUMBUS, Ohio — The Columbus Zoo and Aquarium announced Thursday it has added another member to its gorilla troop, only this time, the birth was a surprise.
The other surprise is that the gorilla who had the birth was previously thought to be a male gorilla.
The Columbus Zoo said on Thursday, keepers noticed Sully — who has lived at the Columbus Zoo and Aquarium with her mother and fellow troop members since 2019 — was holding a baby gorilla.
The zoo keepers initially thought Sully was a male. The zoo explained it’s hard to determine the sex of gorillas.
"Until about age 8, males and females are about the same size, and they don’t have prominent sex organs. As gorillas age, they become sexually dimorphic, meaning males and females look very different. However, males don’t develop their characteristic large size, silver backs and large head bumps [called sagittal crests] until age 12 or later," the zoo wrote in a press release.
In 2019, Sully and her mom, Shalia, came to Columbus from Milwaukee County Zoo in Wisconsin. The Western Lowland Gorilla Species Survival Plan recommended the transfer after Sully's dad died in 2018. At the time of the transfer, Sully was 4-years-old and her mom was 17-years-old.
Zoo veterinarians said when Sully arrived in Columbus, the gorilla was healthy and well-cared for by her mother. Therefore, there have been no procedures done that would have led to the discovery sooner, the zoo said. Sully is 8-years-old now.
Gorillas also don't have specific signs during pregnancy, and experts can't really tell that a baby is on the way.
The zoo said the new baby gorilla appears healthy and is being taken care of by Sully. The care team hasn't approached the newborn yet to give it time to bond with the mom.
They do know that the newborn is a girl.
"We’re thrilled by the addition of another birth for this critically endangered species," the zoo said. "As the 34th gorilla born here since 1956 when the Columbus Zoo became the first zoo in the world to welcome the birth of a baby gorilla, she’s an important part of our work to conserve these magnificent animals."
The zoo said it plans to conduct a DNA test in the future to determine the baby's father.