Charlotte the mysteriously pregnant stingray may already be my favorite animal of 2024. Charlotte’s handlers at a North Carolina aquarium recently revealed that she was carrying several pups, despite her only male company being a pair of sharks. While there was early speculation of some interspecies mingling being to blame here, Charlotte’s pregnancy is almost certainly the result of a known but rare phenomenon called parthenogenesis, a form of asexual reproduction.
Charlotte the round stingray (Urolophus halleri) has been a long time resident of the Aquarium and Shark Lab by Team ECCO in Hendersonville. Sometime last September, Charlotte began to “swell,” and the aquarium initially feared the worst, having found multiple “growths” inside her. Eventually, though, the team’s vet confirmed that she was actually pregnant with up to four pups (the term for stingray young). The aquarium announced Charlotte’s pregnancy in early February.
The strange thing, however, is that Charlotte has had no male stingray suitors as of late. Last July, the aquarium did move a pair of one-year-old white-spot bamboo male sharks into Charlotte’s tank. And afterward, employees did notice bite marks on Charlotte, which can be a sign of shark mating. So the aquarium pondered early on whether it was possible for Charlotte to have successfully bred with the sharks.
Sharks and stingrays are part of the same broad group of fish, but outside experts have strongly shut down this theory. Perhaps the most memorable debunking comes from Demian Chapman, senior scientist and director of the Mote Marine Laboratory and Aquarium’s center for shark research, who told Forbes: “I give the shark the same odds of being the father that I would give Elvis or Bigfoot of being the father—zero.”
Instead, Charlotte’s bundles of joy seem to be an example of parthenogenesis, which isn’t still a mundane event. This can happen when an unfertilized egg cell fuses with a polar body (a cell produced when an egg cell matures that usually has no function) and begins to divide and develop like a typical embryo, albeit with no genetic material from a father. Parthenogenesis has been seen with other sharks and stingrays, but this appears to be the first case ever documented in a round stingray.
Those still hoping against hope to see a sharkray will have to wait a little longer. As of Wednesday this week, Charlotte remains pregnant, oblivious to the rapturous social media attention her miraculous tale has garnered. But it’s expected that she will give birth any day now.