There are a couple of them round about where I grew up in Golspie.. The question is not if they are there - of course they are out there, but whether they are a native species or not.
The fact that there have been sightings on a couple of the islands suggest the latter - why would you bother getting a ferry to set your pet free? Coupled with other facts, like I know a couple of older people who have been seeing big cats all their lives - well before the dangerous animals act in 1976. Also there are records of a pagan ritual called Taigheirm, which involves roasting a succession of live cats on a fire. The cries of the cats were said to be a weapon against demons. Some of the accounts of this rite involve wild cats, but some with large black cats.
This is a quote from a bloke named Horst who witnessed Taigheirm sometime in the 1700's on Mull :-
"The infernal spirits appeared, some in the early progress of the sacrifices in the shape of black cats. The first who appeared during the sacrifice, after they had cast a furious glance at the sacrifices, said—Lachlain Oer, that is, 'Injurer of Cats.' Allan, the chief operator, warned Lachlain, whatever he might see or hear, not to waver, but to keep the spit incessantly turning. At length the cat of monstrous size appeared; and after it had set up a horrible howl, said to Lachlain Oer, that if he did not cease before their largest brother came he would never see the face of God.
Lachlain answered that he would not cease till he had finished his work if all the devils in hell came. At the end of the fourth day, there sat on the end of the beam in the roof of the barn a black cat with fire—flaming eyes, and there was heard a terrific howl quite across the straits of Mull into Mowen."
Very theatrical!