‘Science mystery’: Stingray impregnated by shark in North Carolina?

Almost a week ago, the Aquarium & Shark Research Institute by Team ECCO in Hendersonville, North Carolina, revealed a stingray that Charlotte was pregnant with. The news was revealed in a Facebook post on Tuesday. Because Charlotte became pregnant without the involvement of a male stingray, they declared this a “once-in-a-lifetime scientific mystery.”

The aquarium kept the news secret for the past three months. Australian Aquarium veterinarian Dr. Robert Jones and Arizona State University doctoral candidate Becca Campbell confirmed this fact through ultrasound images.

How did Stingray Charlotte get pregnant?

In a conversation with ABC 13 News, the North Carolina Aquarium said there are two ways the stingray could have become pregnant.

The first process required parthenogenesis, an unusual method of asexual reproduction. According to this natural form of asexual reproduction, fertilization is not required for the egg to develop into an embryo. The aquarium also explained that if such a process were to proceed, Charlotte’s pup would be a clone of Charlotte.

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Team ECCO Executive Director Brenda Lamar suggested a second way this could have happened. Without asexual reproduction methods, Charlotte could have been impregnated by a one-year-old male white shark. No male stingray was found in the same tank as her, but the shark had been moved there in July 2023.

Lamar added that when he noticed the bite mark on Charlotte (which was on the end of the fin), he moved the other fish where it was nibbling on Charlotte. But the problem persisted. He also acknowledged that bite marks are a sign of shark mating.

Charlotte’s pregnancy became apparent in September when aquarium staff noticed “swelling.” At first, they mistakenly thought it was cancer. Dr. Robert Jones eventually determined that the stingray had three to four developing eggs. The aquarium expects her to give birth to four pups at any time. The gestation period for stingrays is approximately 3 to 4 months.

It has not yet been announced whether Charlotte’s puppies are “potential hybrids” and that will only be known at birth. DNA testing can help confirm these suspicions.

As people continue to make personal statements on the aquarium’s Facebook page, staff recently released another statement. “In the wake of all the interest and confusion surrounding Charlotte, we here for wonder and research, whether you want to express a personal position or make comments that prove yourself or your knowledge to other readers. Don’t use the platform of… Just because something is wrong, I ask. Just because it hasn’t happened or isn’t documented doesn’t make it impossible. Science is discovery…” said the Aquarium and Shark Lab by Team ECCO.