At first glance, grey seals look like they can do no wrong with their large, dark eyes and their Labrador-like faces they are often perceived as the gentle giants of the ocean.
But it turns out these seals may not be as innocent as they look.
First disturbing pictures were released of male fur seals pinning down penguins to try and mate with them reports Mirror UK.
Those shocking images on the beaches of Marion Island in the Indian Ocean have been followed up with an equally shocking revelation off the coast of Britain and Holland.
Scientists have now discovered that grey seals are responsible for killing hundreds of porpoises and mutilating many more.
Experts even believe that they could attack humans swimming in the sea. While seal attacks on humans are rare they are not unheard of.
British marine biologist Kristy Brown, 28, was snorkeling off the Antarctic Peninsula in 2003 when a leopard seal grabbed her in its jaws and dragged her to her death beneath the icy waves.
Seal attacks aren’t just confined to arctic wastelands.
A common harbor seal sank its teeth into the hand of five-year-old Caleigh Cunning and dragged her off the docks into the water in Canada in 2009 – the frightened young girl escaped only with an injured hand, while a monk seal attacked a tourist while she was snorkeling in Hawaii the same year.
Scientists at the Institute for Marine Resources and Ecosystem Studies in Holland studied the remains of over 1,000 severely scarred or injured porpoises washed along North Sea coastlines during the last decade.
For years, experts were scratching their heads.
Some blamed boat propellers; others claimed the wounds were from scavengers after the porpoises were caught in fishing nets.
But now scientists have discovered the true culprit by using CSI-style forensic techniques to identify grey seals DNA left behind by their attackers.
Biologist Dr. Mardick Leopold, who led the study said: “Many of the mutilated porpoises were found on shores used frequently by human bathers and surfers and there would appear to be no reason why humans may not be at risk from grey seal attacks.”
Britain houses 180,000 grey seals, most living along the Scottish coastline.
They can grow up to 11 feet long and weigh more than 660 lbs., making them Britain’s biggest carnivore.