 Although other storm kelpies are reported as inhabiting the Gulf of <unk> , described by poet , writer and folklorist Alasdair Alpin MacGregor as " the fiercest of the Highland storm kelpies " , the blue men are confined to a very restricted area . According to Donald A. Mackenzie they have no counterparts elsewhere in the world or even in other areas of Scotland ; such limited range is rare for beliefs in spirits and demons . Folklorist and Tiree minister John Gregorson Campbell states that they were unknown in Argyll on the nearby coast of the mainland for instance , although Church of Scotland minister John Brand , who visited <unk> in Shetland in mid @-@ 1700 , recounts a tale of what may have been a blue man in the waters around the island . In the form of a bearded old man it rose out of the water , terrifying the passengers and crew of a boat it was following . 
