Greenland Shark, One of Earth’s Longest Living Animals, Captured Near Belize: NPR
Researchers tagging tiger sharks off the southern coast of Belize couldn’t believe their eyes when they recently spotted another type of fish. It turned out to be a Greenland shark, which is usually found in the Arctic and can live to be over 500 years old.
The team of scientists thought the shark was dead when they finally brought it to the surface. Unlike the tiger sharks they were looking for, this particular shark had black, worn skin and pale blue eyes. Devanshi Kasana, Ph.D. candidate at Florida International University’s Predator Ecology and Conservation Laboratory, said the shark looked “really, really old”.
“It was just very surprising and confusing,” she said. “As soon as it entered our field of vision, we saw a black figure that grew bigger and bigger. When it came to the surface, none of the crew with all their combined fishing experience n hadn’t seen anything like it.”
Kasana and his colleagues published an article about the capture in the newspaper Marine biology in July.
Kasana said the find is particularly exciting because it suggests these sharks, which were thought to exist mainly in the Arctic, can also be found in the tropics.
Greenland sharks can probably live over 500 years
Scientists have more questions than answers about the Greenland shark. According to the National Oceanic and Atmospheric Administration, these sharks are the longest-lived vertebrates on the planet, living possibly over 500 years. And that’s just an estimate, because there’s no definite way to tell how old they are.
The reason they live so old may have something to do with their slow pace of life – very, very slow. Greenland sharks grow about a third of an inch a year and can reach over 20 feet in length. And researchers believe that sharks only reach sexual maturity after the first 100 years of their lives.
According to Kasana, some scientists have speculated that the Greenland shark can be found all over the world, if one knows where to look. They like cold water, which is why they are found in the Arctic. However, they have also been discovered as far south as off the coast of Georgia, thousands of feet below the surface of the ocean.
The theory is that the closer sharks are to the equator, the further researchers have to go to find them. And they go deep, over 7,000 feet, according to NOAA.
The hitch was unexpected
Kasana said their capture was strictly accidental. On April 22, she and her team were working with members of the Belizean shark fishing community and the Belize Fisheries Department to lay lines along Glovers Reef, located about 30 miles off the coast. Reef waters can be as shallow as 25 feet, but steep drops can reach over 2,000 feet deep.
“It suddenly tilts and the depth gets really deep really fast,” Kasana said. “We believe the line dragged from a much shallower depth to the drop off, which is why we ended up catching this individual.”
A report of the encounter published on July 15 claims that it is the first Greenland shark to be discovered in the western Caribbean. Knowing how rare the experience was, Kasana said his team had considered buying a lottery ticket if they ever encountered another.
“If we were to catch another individual it would be luck, we don’t set our lines to target Greenland sharks,” Kasana said.
When they brought the shark back, it looked extremely old, she explained. And although they briefly considered marking it, they didn’t want to accidentally harm or kill the shark in the name of science. Instead, Kasana and her team measured the shark, took notes and a photo, and sent it on its way.