species in the 19th century, having its eyries in great pine trees of the remnant of the Caledonian Forest. The kite was finished but a few years afterwards. The Harvie-Brown Vertebrate Fauna Series are good sources of information on the last haunts of all these raptors. The white-tailed or sea eagle has been the last to go. Shetland has the last breeding record in the present century. The West Highland and Hebridean coasts, being nearer to extensive sheep-farming interests, lost their sea eagles rather earlier. By 1879 they had gone from Mull, Jura and Eigg. The species finally ceased to breed in Skye, the Shiant Isles and the north-west mainland about 1890. It is all a dismal story; and it is a matter for doubt whether, should these species try again to colonize this country, they would be allowed to breed in security. The vested interests of game preservation (by no means dead in a Socialist Britain), of a decrepit hill sheep-farming industry in the West Highlands and Islands, the pressure of egg collectors and irresponsible gunners, are heavy odds.
A local extinction is worth noting, namely, the ptarmigan in the Outer Isles. Their last haunt was on Clisham, Harris, the highest hill in the Hebrides. Seton Gordon in his recent book A Highland Year (1944) says that rabbits became very numerous on the drier slopes of the hill, and that ferrets were turned down to cope with them. He says the ferrets also preyed upon the ptarmigan and are in his opinion responsible for their extermination. This animal achieved what the related pine marten failed to do in its day in the Forest of Harris.
There is one invertebrate extinction to be recorded, the oyster. The northern oyster was common in many sheltered shallow bays up and down the West Highlands, but it has now gone, probably due to gross overfishing, with possibly a run of low-temperature summers which would hinder breeding. Experiments have been made in reintroduction, but the southern oyster from French waters has been used, and as might have been expected, has not been successful. The temperature of the water does not reach and remain at 60° F. for a long enough time.
The status of our two British seals, the Atlantic grey seal (Halichoerus gryphus) and the common or brown seal (Phoca vitulina), is interesting as an example of the influence of man on the species. The common seal is truly common though local: it occurs in large numbers in the Tay estuary where it is regularly hunted, but without complete success owing to the sanctuary given by the sand banks; it is common in Orkney, and the seas of Shetland hold very large numbers. The common seal is of much less frequent occurrence on the West Highland coast, though there are pockets of twenties and thirties in some of the sea lochs and among the groups of islands. The Atlantic seal is much commoner on this coast though it favours the more outlying places.
The common seal is immensely more damaging to nets than the Atlantic seal, but its habits are such that any attempts by man to lessen its numbers severely have little success. When the young are born they go to sea with the mothers immediately and the adults spend no more than a few hours at a time lying out on rocks and sand banks. The species does not flock to some traditional breeding place as does the Atlantic seal. We shall study the life history of this latter species in a later chapter; our concern with it here is in the habit of retreating to more or less remote islands to breed, and in spending some weeks out of the water. The Atlantic grey seal is at the mercy of man at such a time, for he finds gathered at these places the population of a great length of coastline, with the animals at a severe disadvantage.
The grey seals (Plate 28 and Plate XXX) were regularly hunted in the Hebrides during the autumn breeding season, without reference to age, sex or condition of the animals; for the visits to the nursery islands were governed by the state of the sea. The result was a diminution in numbers which did not become dangerous until the 19th century when the species was faced with the fact which I have mentioned and repeated elsewhere in this survey of Highland natural history—danger for the species comes when the toll taken is for export and not for the limited and constant needs of a resident human population. The skins of the Atlantic seals were being bought and resold by the Danish Consul in Stornoway. The fishery was wasteful in the extreme and quite unorganized. Then came a remarkable relief for the seals in cheap rubber boots for the fishermen, and synchronously, almost, the arrival of cheap and clean paraffin for lamps. Rubber boots were much less trouble in every way than those of seal skin, and only those who have tried the smoky flame of seal oil can fully appreciate the boon of paraffin. The seals got some respite except for the fact that the hunting had become a traditional social occasion which had to be gradually broken down. Happily, the Government made an Order prohibiting the slaughter of Atlantic grey seals during the whole of their breeding season. The species has increased and is now numerous again to an extent it cannot have known for centuries. It is spreading to islands and mainland coasts from which it had long disappeared, and is now a feature of the natural history of the West which anyone can hope to enjoy, and have the opportunity to see and watch in the course of a short holiday. This story of an animal’s survival is an example of the importance of human ecology in relation to that of the animal. No British mammal could be more easily exterminated, because of the nature of its breeding habits. Its future is entirely in man’s hands.
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