Greenland Shark Died From Brain Infection Never Before Seen in Species
An extremely rare Greenland shark that washed up on the U.K coast died of a brain infection that has never before been recorded in the species.
Rosie Woodroffe—a biologist at the Zoological Society of London (ZSL) Institute of Zoology—found the dead shark, washed up on Newlyn beach in Cornwall, on March 13. The rare find was taken in for a post-mortem, which is likely the first one ever conducted on the species in the U.K.
Greenland sharks have the longest lifespan of any vertebrate. Scientists think they can live for at least 250 years, if not up to 500 years. The shark was found to be 100-years-old.
The post-mortem, carried out by Cornwall Marine Pathology Team, found evidence of meningitis caused by a type of bacteria called Pasteurella. The brain was discolored and congested, and fluid around the brain was cloudy, indicating the infection, ZSL said in a press release.
Greenland sharks are a mysterious and poorly understood species. They are hardly ever spotted and live in deep waters of about 650 to 1,640 feet below the surface of the ocean. The sharks only ever venture up to the shallows of bays and river mouths in the winter.
The infection would have caused the female shark to venture out of her usual, deep water habitat, causing the subsequent stranding, ZSL said.
Marine strandings are a common phenomenon however usually involve whales and other cetaceans. Scientists are not sure exactly what causes them, but disease has been a factor before. In most cases, stranded animals die.
James Barnett of the Cornwall Marine Pathology Team, told Newsweek that brain infections have been found in stranded marine wildlife before, however, at this time there is not enough data to see whether it is a cause for concern.
"The one other thing that stood out on the post-mortem was that the eyes were badly damaged," he said. "There is a copepod parasite that is known to attach to the eyes of Greenland sharks and can cause damage to the surface (cornea). No copepods were visible on the eyes of this shark but it is possible they may have been lost prior to the animal being retrieved."
Just a few days before the body was found, French research organization the Association for the Study and Conservation of the Selachians said there had been a sighting of a Greenland shark off the coast of island of Ushant.
A closer look at the shark's tail during the post mortem confirmed it was likely the same one.
Rob Deaville, project lead of ZSL's Cetacean Stranding Investigation Programme (CSIP),said in a press release that this "unfortunate and extraordinary stranding" has allowed scientists to get an insight into the poorly understood species.
"Discovering that this shark had meningitis is likely a world's first, but the significance of this in terms of any wider stressors is unknown. Ultimately, like most marine life, deep sea species such as Greenland sharks may also be impacted by human pressures on the ocean but there is not enough evidence at this stage to make any connections," Deaville said.
