A snorkeler has been bitten by a shark and has suffered a leg injury. So what, you might ask? Although shark attacks are rare several are reported each year. What is of interest with this incident is the location.
The attack took place off the costal waters of the U.K., close to the county of Cornwall. The attacking predator was a blue shark. The blue shark (Prionace glauca) inhabits deep waters in the world’s temperate and tropical oceans.
Blue sharks are 3.1 metres in length and while they swim relatively slowly, they are capable of rapid acceleration. Blue sharks rarely bite humans, although a handful of attacks have been reported.
Blue sharks are endangered, and they are listed as Near Threatened on the IUCN Red List. The International Union for Conservation of Nature Red List of Threatened Species is the world’s most comprehensive inventory of the global conservation status of biological species.
As to why blue sharks are found so close to U.K. waters, the reason for this is climate change. As the oceans warm, the migratory patterns of sharks are altering. The new migratory patterns are also attracting more divers.
The migratory patterns of sharks are complex, with the boundaries within shark populations and in particular the movements of individual sharks affected by a range of social and ecological factors.
The one of these ecological factors is heat is not of surprise, given the impact of global heating, and neither is the fact that sharks, like other animals, have an ideal range for temperature. Above or below this temperature, sharks are not able to perform basic functions optimally. A common pattern across many species of shark is that they are shifting northward as the oceans continue to warm.
One such pattern, over the past decade or so, has been with blue sharks being reported off the coast of Cornwall, especially off the west coast. Their migration from Atlantic Ocean into British waters occurs in the summer.
With the recent incident within British waters, a Maritime Coastguard Agency spokesperson told the BBC that a coastguard team went to Penzance Harbour to pass the casualty into the care of an ambulance.
The company that organised the dive, Blue Shark Snorkel Trips, said (as quoted by The Guardian): “As we know, these things can happen when we choose to interact with wild animals in their own environment.
“The last thing we want is to let speculation drive the media into a world of bad press for the sharks, under no fault of their own. We immediately enacted our emergency response plan, with first aid being carried out on the person involved.”
