From the XVIII century onward, the fairies have been said to have departured or to be in decline. People do not see them any more and some argue that the Faeries will eventually disappear as men have stopped believing in them.
Other put forward pollution, urbanization, science as the main causes for their disparition.
A French tale says that during each century with an odd number like 2100, the fairy tribes of all kinds are said to be visible or to reappear among men, and to become invisible or to disappear during each century with an even number like 2000.
Somewhere at the beginning of the 19th century, Hugh Miller recorded what was supposed to be the final departure of the fairies from Scotland at Burn of Eathie.
On a Sabbath morning… the inmates of this little hamlet had all gone to church, all except a herd-boy, and a little girl, his sister, who were lounging beside one of the cottages; when, just as the shadow of the garden-dial had fallen on the line of noon, they saw a long cavalcade ascending out of the ravine through the wooded hollow. It winded among the knolls and bushes; and, turning round the northern gable of the cottage beside which the sole spectators of the scene were stationed, began to ascend the eminence toward the south. The horses were shaggy, diminutive things, speckled dun and grey; the riders, stunted, misgrown, ugly creatures, attired in antique jerkins of plaid, long grey cloaks, and little red caps, from under which their wild uncombed locks shot out over their cheeks and foreheads. The boy and his sister stood gazing in utter dismay and astonishment, as rider after rider, each one more uncouth and dwarfish than the one that had preceded it, passed the cottage, and disappeared among the brushwood which at that period covered the hill, until at length the entire rout, except the last rider, who lingered a few yards behind the others, had gone by. ‘What are ye, little mannie? and where are ye going?’ inquired the boy, his curiosity getting the better of his fears and his prudence. ‘Not of the race of Adam,’ said the creature, turning for a moment in his saddle: ‘the People of Peace shall never more be seen in Scotland.’
Hugh Miller, The Old Red Sandstone
Yet, however often they may be reported as gone, the fairies still linger. In Ireland the fairy beliefs are still part of the normal texture of life; in the Highlands, Islands or Brittany the traditions continue.