MALI: Cannibalistic attacks by grey seals rather than collisions with ship propellers are the likely cause of a spate of mysterious “corkscrew” seal deaths in Scotland, according to a report.
Marine experts had been left baffled by unusual spiral injuries found on a number of dead seals washed up around Scotland.
Between 2009 and 2014, 86 carcasses were found with single, smooth-edged cuts that spiralled around the body.
Examinations of the damaged corpses led to the conclusion that the seals had died as a result of getting sucked into ducted boat propellers – used on vessels that need to move slowly or remain stationary.
Other research has suggested shark attacks could have caused the massive injuries.
But new research from the University of St Andrews suggests male grey seals are most likely to blame.
Scientists at the university’s Sea Mammal Research Unit (SMRU) witnessed an adult male grey seal killing five young seals at a colony on the Isle of May, biting off chunks of blubber and leaving the dead animals with distinctive spiral injuries. Combined with recent similar evidence from Germany, the findings suggest that such predatory behaviour may be more common than previously thought and could explain the unusual clusters of injured seals found in Scottish waters.
