Pregnant Stingray Could Have Been Impregnated by Shark: 'A Science Mystery'

The Aquarium & Shark Lab by Team ECCO said the stingray shared a tank with a male shark and had bite marks on her fins indicative of shark mating

A stingray living in a North Carolina aquarium might have been impregnated by a shark.

The Aquarium & Shark Lab by Team ECCO in Hendersonville announced in a Facebook post on Tuesday that its stingray Charlotte is pregnant. The aquarium called Charlotte's pregnancy "a once-in-a-lifetime science mystery" because, at the time she was impregnated, there were no male stingrays in the tank with her.

The aquarium explained in a statement to ABC 13 News that there are two ways in which Charlotte could have become pregnant.

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One is a rare asexual reproduction process called parthenogenesis, in which eggs develop into an embryo without fertilization. If the pups were produced this way, they will be clones of Charlotte.

Brenda Ramer, executive director of Team ECCO, explained to ABC 13 News that the second way Charlotte could have become pregnant is by a 1-year-old male white spot bamboo shark that was moved into the tank with her in July 2023.

"We started to notice bite marks on Charlotte, but saw other fish nipping at her, so we moved fish, but the biting continued," Ramer said, adding that bite marks indicate mating in sharks. Charlotte had bite marks on the edges of her fins, she noted.

The staff discovered Charlotte's pregnancy in September after first noticing "swelling" in the animal that they initially thought was cancer, Ramer told the outlet. The aquarium's vet, Dr. Rob Jones, later confirmed that the stingray was growing three to four eggs.

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Charlotte is thought to be carrying up to four pups and could give birth at any time since the gestation period for stingrays is between three and four months.

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The aquarium will only know if the pups are clones of Charlotte produced via parthenogenesis or if they are what Ramer called a "potential mixed breed" when they are born. DNA testing will likely be conducted on the pups after their arrival.

PEOPLE reached out to Aquarium & Shark Lab by Team ECCO for further details about the stingray's unusual pregnancy.

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