Islands of Ireland: Did a pirate leave anything behind on West Cork's Rinneen Island?

Islands of Ireland: A mute swan nests on Rinneen Island, Dunmanus Bay, County Cork. Picture: Dan MacCarthy
The mute swan poses regally on its nest of reeds and seaweed at this tiny West Cork island, a solitary protector of this tiny island or islet. And not mute, of course, just not as boisterous as our other two species, the whooper and Bewick's swan.
The island is a mere 20m off Dunmanus Pier and looks across towards the Sheep’s Head Peninsula. It is a low-lying, unremarkable-looking spot, but therein lies the story.