The Unexpected Shark Discovery Scientists Made In The Caribbean Sea

In the inviting, warm, blue-green waters off the coast of Belize divers often encounter sea turtles, rays, and the occasional venomous lionfish. But researchers tagging tiger sharks with fishermen there have made a stunning discovery: a Greenland shark, one of the world's oldest and most mysterious creatures, living thousands of miles away from its arctic home (via Forbes). The shocking find, published in the journal Marine Biology in July of 2022, raises many questions. Among them: Why was it there? And is this oddity the only one?

Not a lot is known about the Greenland shark, in large part because they live deep in the icy waters of the Arctic and North Atlantic Oceans (via Britannica). Spotting one is rare enough that researchers initially didn't realize what they'd found. "At first, I was sure it was something else, like a six gill shark that are well known from deep waters off coral reefs," Devanshi Kasana said in a press release from the Florida International University. The Ph.D. candidate in the school's Predator Ecology and Conservation lab went on to say, "I knew it was something unusual and so did the fishers, who hadn't ever seen anything quite like it in all their combined years of fishing."

Kasana reached out to her Ph.D. advisor, who suspected it was a Greenland Shark. An assessment later confirmed by several experts found it was definitely a member of the sleeper shark family, which includes Greenland sharks, and most probably either a Greenland shark or a Greenland shark hybrid, according to the university news release.

While there's a lot researchers don't know about the Greenland shark, including why one would be found thousands of miles away from its home turf, they do know some things. For one, the creatures have a remarkably long life span, often living up to 400 years, making them the longest living vertebrate on earth (via CNN). They belong to a family of sharks that inhabited the oceans for 100 million years, making their first appearance way back in the days of the dinosaur (via Mashable). They can grow up to 23 feet in length and weigh more than a ton, according to Encyclopedia Britannica. What's also unique, albeit disturbing, about the Greenland shark is most of them are blind, the result of worm-like parasites that latch on to their eyes (via SharkSider).

But why was this cold-water dweller lurking in tropical Belize? Researchers found it in an area where the sea floor drastically drops off from about 1,500 feet to nearly 10,000 feet (via the Florida International University's (FIU) release). The deeper water means cooler temps, the exact type of water an Arctic species would appreciate. Because the creatures live in such deep water, researchers believe there actually could be more of them living undetected all over the world (via FIU). "I doubt it's the only one," said Dr. Demian Chapman, one of the co-authors of the study that appeared in the journal Marine Biology.

The shark was found in an area called Glover's Reef, where Dr. Chapman (above), one of the study's co-authors, has been working on a two-decade-long project with government organizations, local fishermen, and other scientists. Their work has helped create regulations that protect sharks, including a ban on shark fishing in some 1,500 square miles of habitat around Glover's Reef and two other areas (via the MOTE Marine Laboratory). Those involved say the collaborative effort is good for both conservation and discovery (via FIU's press release). Comedian Ellen DeGeneres helps fund projects to research and protect sharks in Belize. In fact, she helped fund the tiger shark tagging project that led to the big discovery (per The San Pedro Sun). Dr. Chapman made an appearance on her talk show to discuss his work in the area (posted on YouTube).

While the Greenland shark was once described by The New Yorker as "among nature's least elegant inventions," the mysterious shark holds an obvious fascination for those who helped haul it up from the depths. Omar Faux, one of the fishermen involved, was quoted as saying in the FIU's release, "I am always excited to set my deep water line because I know there is stuff down there that we haven't seen yet in Belize, but I never thought I would be catching a Greenland shark."