Cu Sith

The Cu Sith ("fairy dog") is a supernatural hound of Scottish Highland and Hebridean tradition, described with unusual precision: about the size of a young bull or a large calf, with a shaggy dark-green coat, a long tail coiled or braided on its back, and enormous paws that leave prints in mud and snow. It moves silently, in a straight line, and hunts by day; but its bark is the danger, for it gives three great bays as it ranges, and a traveller who has not reached safety by the third is said to be overtaken. In some accounts its special errand is to carry off nursing mothers to the fairy knolls to suckle fairy children.

The Cu Sith belongs to the wide British and Irish family of spectral dogs, the Black Shuck of East Anglia, the Barghest of Yorkshire and others, most of which are omens of death; but its green colour and its silent, purposeful gait are distinctively its own. It is chiefly a creature of oral Gaelic folklore rather than of any written mythological text.

The cu sith is described with unusual consistency in the Highland material. It is the size of a young bull, its shaggy coat is dark green, its tail is long and either coiled on the back or plaited, its paws are the width of a man's hand, and it moves in a straight line and in silence. Silence is the striking part, because a dog of that size ought to be heard, and the tradition makes a point of it.

It hunts silently and then bays three times. The bays carry a long way and they are a countdown: anyone who hears the third without reaching shelter is taken, and in some accounts the dog is fetching a nursing woman to the fairy mound to feed their children. That errand ties the creature to the wider Gaelic body of belief about the taking of women and infants, which is where a great deal of the practical fear in that tradition was actually located.

Britain and Ireland have many spectral dogs, and most of them are black. Black Shuck in East Anglia, the barghest in Yorkshire and the church grim elsewhere all share the size, the eyes and the ill omen. The colour is what marks the cu sith out. Green is the fairy colour throughout Gaelic tradition, and it places the animal with the sith rather than with the ghosts.