Aquarists at Tennessee Aquarium were surprised to discover a new arrival waiting for them when they checked the swell shark tank last month. Swimming between its parents was a new swell shark baby. Also known as “glow sharks” because they glow under ultraviolet light, take a break and watch the little one glow as it swims about in its tank.
“We call them that because they biofluoresce — they don’t make their own light, but they reflect light in a fluorescent manner,” explained Senior Aquarist Kyle McPheeters, who first spotted the four-inch youngster, in a statement.
Swell sharks live in the deeper parts of the ocean where only blue light is ablee to penetrate. They have specially adapted eyes with a part yellow lens – so while to a human they would appear brown, to another shark they look like they are glowing.
The "swell" part of their name comes from an unusual defense system. These sharks are capable of swallowing large amounts of seawater, causing them to swell in size and making it much harder for a predator to bite them or flush them out from a rocky hiding place.
These new arrivals are the first babies to be hatched at a zoo or aquarium in more than a year. While these babies may be tiny at the moment, swell sharks can grow to around a meter in length (3 feet). They are found along the west coast of the Americas from California to Mexico but can also be seen along the coast of Chile.
“When we have eggs coming from the adults, that’s exciting in itself, because it means we have a healthy environment where they feel safe reproducing,” McPheeters says. “But then to come in and see that come full circle and come to fruition with a baby shark hatching from its egg is really exciting.”
The team at the aquarium hopes these new youngsters will teach their visitors more about this exciting species and help dispel some myths surrounding shark species.
“Sharks play a vital role in the ocean,” he says. “Just like land-based predators such as wolves and lions, they help to balance the food web and keep animal populations healthy by weeding out sick or injured individuals.”