The half-blind shark which was caught at a coral reef off Belize in Central America (Pic. Courtesy livescience.com)
Any phenomena or situation which is not usual has the scientific community sit up, providing a new direction for investigation. Latest in this was the discovery of a half-blind shark that usually inhabits freezing waters of the Arctic at a coral reef off Belize in Central America.
Interestingly, the blindness is often caused due to a parasite which attaches itself to the creature’s corneas.
As per a report in livescience.com, this relic fish with odd appearance with blue eyes was hooked by Belizean fishers and a biologist in the Caribbean tropical waters in April.
Following investigation and study by the scientists it was pointed that this unusual creature may be either Greenland shark or a hybrid of this species belonging to the sleeper shark family. This was the very first instance when this fish had been spotted in this region.
Caught at Glover’s Reef, the mere appearance of the animal caught the attention of the crew who knew they were on something different. In a statement, Devanshi Kasana, who is a doctoral candidate at Florida International University’s Predator Ecology and Conservation lab, and was part of the crew said: "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 led the study of this strange-looking fish.
The shark measured approximately 12 feet in length and was released before it could be identified. The family to which this fish belongs to – the sleeper – are usually found in the coldest and deepest ocean waters. The Greenland sharks live in the North Atlantic and Arctic oceans.
Not much is known about these sharks and this new find gives credence to the theory that these fishes are more widely spread than thought of earlier. The experts feel that their entire globe could possibly be their home and in tropics they dwell at greater depths in which they find low temperatures of their choice.
Found thousands of miles away from where its habitat is, this shark was stumbled upon when Kasana was working with Belizean fishermen to tag tiger sharks as part of her doctoral research.
The shark had to be left off since a looming storm threatened its safety and thus, the team could not take its genetic sample.
Kasana and her team watched the footage and images of the shark which were shot during its captivity. What they discovered was that it had shared features with Greenland sharks and other sleeper sharks. These included rounded snout, low and rounded pectoral fins and an eye parasite.
The study pointed out that the fish is slack and slow-moving just like sleeper sharks when they are captured.
Having finished their study, scientists summed up that the fish which was in captivity was probably a Greenland shark or a hybrid – between a Pacific sleeper shark and a Greenland shark.
Glover’s Reef may be in the tropics but its water is deep and its slopes drop from 1,600 to 9,500 feet below the surface, the statement said. This makes the place conductive for the sleeper sharks and thus they may be found in this area, said the scientists.
These sharks have a very long lifespan and it is believed to be at least 272 years and go beyond 400. Their diet includes everything from fish to polar bear.
Details of the study were published in the journal Marine Biology.