Sea-Birds. James Fisher

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СКАЧАТЬ of Brünnich’s and common guillemots. Some of the buttresses rise fourteen hundred feet sheer from the sea, and, as Bertram and Lack say, “have been described with justice as the finest bird-cliffs in the Northern Hemisphere.” However, those of St. Kilda are (in one place) also fourteen hundred feet high, and are more varied, with a better-known history. Those who have seen both may think St. Kilda finer, though Bear Island has more birds and is more magnificently sinister. It certainly has a higher sea-bird population than any comparable place in the North Atlantic-Arctic; though it seems to have competitors in the Pribilov, Aleutian and Kurile Islands and other parts of the North Pacific. But there are many great bird-stations besides Bear Island and St. Kilda, where the observer may behold a community of a million birds or more. On the basalt cliffs of the Faeroes, particularly north-west Streymoy, he may find this number. Perhaps nowhere in Iceland is there a cliff-site with a million birds, but there are many rocks with many thousands, from the Westmann Isles in the south to Grímsey in the north; from Latrabjarg in the west to Skruður and Papey in the east. Jan Mayen has at least a million sea-birds; and there may well be millions at more than several places in Spitsbergen; perhaps on the hills of Horn Sound, Cloven Cliff off the north-west, Magdalena Bay and Brandy Bay in North-east Land; almost certainly on the Vogel Hoek of Prince Charles Foreland, the great auk hill of Advent Bay, and the dolerite Alkrange of Hinlopen Strait. A pioneer ecologist and student of animal numbers (Elton in Longstaff, 1924) wrote of the Alkrange:—

      “It is impossible to describe the multitudes of the Guillemots on the bird cliffs. The place was teeming with them: literally hundreds of thousands. The cliffs are made of columnar dolerite which weathers into pinnacles and which rise several hundred feet sheer out of the sea. On the numerous narrow ledges the birds were so crowded that there was room for no more. The rows of black and white birds rising in tiers up to near the top, and the ghostly noise of the combined twitter made by them, made it seem as if one was in a vast opera house, packed with crowds of people in white shirt-fronts and black tails, all whispering comments on each other and rustling their programmes.”

      It seems clear that either the little auk or Brünnich’s guillemot is the most abundant bird of the north. It is hard to decide which; the little auk colonies are perhaps fewer, and certainly less obvious as dense loomeries, because the birds nest in crevices and not on flat open ledges. But the dark cloud of circling, twittering dovekies betrays their density, and we believe with Salomonsen that their actual numbers are greater. Nevertheless, some Brünnich’s guillemot loomeries are vast, and those at Bear Island, Jan Mayen and Spitsbergen are not the only ones that are stupendous. The largest loomery in the U.S.S.R. is probably that at Bezymiannaya Bay in Novaya Zemlya, where S. K. Krasovskii (1937) has estimated that about 1,600,000 Brünnich’s guillemots (birds, not pairs) nest. But Salomonsen (1944) has estimated that in 1936 over two million Brünnich’s guillemots (birds) bred at the rock Agparssuit (Cape Shackleton), north of Upernavik in West Greenland. This was about half the population of this species in Greenland. There are many other huge bird rocks in Davis Strait and Baffin’s Bay; in West Greenland several on Disko Island, in Umanaq Fjord (notably Sagdleq, which may have a million Brünnich’s) and in the Upernavik district (notably Qaerssorsuaq, or Sanderson’s Hope, where the guillemot cliff is at least three miles long and over three thousand feet high and has two hundred thousand Brünnich’s), and several in the Thule district in the far north-west, notably Saunders and Hakluyt Islands, and Cape York, which contains what is probably the largest little aukery in the world;^* nobody has been able to guess how many millions nest there.

      Other huge bird-colonies in the western Arctic are to be found in Ellesmere Island, North Devon Island, Bylot Island and Baffin Island. Indeed, throughout the Arctic, where the naked rock escapes from the clutch of ice, and precipices rear to the sky from shores, the kittiwakes and dovekies, the puffins and guillemots, the fulmars, the glaucous gulls and pale herring-gulls, make their nests, and operate from them to the feeding grounds, to the leads in the ice, the convergences of tide and current, the upwelling zones at glacier faces and by the side of big icebergs. And below the cliff-ledges is the tell-tale of the bird city, rich plants, sudden patches of green in the arctic drab, green swards indeed, bright yellow-green grass; the round leaves of scurvy-grass, lush, six times as high as in the barren places, which means six inches high. On the slopes of scree and talus and broken rocks below is a special mat of little flowering plants, benefiting from the bird-dung leached and washed down from above; perhaps not the purple opposite-leaved saxifrage, which shuns this community (it is too rich for it), but alpine foxtail, the arctic poppy, the arctic buttercups, and the polar creeping willow; and tufted, drooping, alpine brook saxifrages; and the alternate-leaved golden saxifrage; and alpine mouse-ear chickweed, various arctic whitlow-grasses, poas and a woodrush, and Wahlbergella; and sometimes carpets of Jacob’s ladder. There are many mosses, too, with bright colours; and all over these arctic cliffs—not only below the bird ledges—grow lichens. One of them is the beautiful orange Caloplaca elegans; it grows all over the bird rocks of Spitsbergen, shines yellow orange among the dark rock and green grass-ledges of the fulmar-haunted bastions of Disko in West Greenland, and colours from top to bottom the mighty buttresses of Cape Searle in eastern Baffin Island, the site of what may be the world’s largest fulmar colony. Grey fulmars sit on green ledges above orange rocks.

      In Britain, St. Kilda is the greatest sea-bird station. Upon its thousand-foot precipices nests one of the densest communities of vertebrate animals in the North Atlantic—probably the densest south of the Arctic Circle. The gannets of Boreray and its stacks have about seventeen thousand nests—one-sixth of the world population of this species. A quarter of Britain’s fulmars (up to forty thousand pairs) nest on St. Kilda. Undoubtedly more than a million puffins’ eggs are laid on St. Kilda in a normal year; the question is, how many million? There are seven separate puffin-slopes on St. Kilda each of which is larger than the largest puffin colony anywhere else in the British Isles, even the largest puffinry in the mossy talus-slopes of the Shiant Isles, where blocks of columnar basalt lie below the cliffs like the forgotten bricks of a child. The puffin is certainly one of the most numerous birds in the North Atlantic. In his monograph on the puffin (1953) Lockley estimates a minimum world population of 15,000,000 adults.

      From the study of the ecology of animals we are learning that their numbers are controlled primarily by the amount of food they can get, and only secondarily by their parasites and predators; and parasites are probably more important than predators. But there are exceptions to this; and the chief one is when the predator is man (another is when new predators are introduced through his agency). Except in a few places such as most of Greenland, Jan Mayen, Spitsbergen, Franz Josef Land and a few other arctic islands, man is, or has been, the most important predator of sea-birds. He has been one, of a kind, ever since he has been Man—even before; for there is ample evidence that during the second of the two advances of the ice in the second of the two glaciations of the Great Ice Age, some of the latest members of the species Homo neanderthalensis ate great auks. This was about twenty thousand years ago; the Neanderthals left their auk bones in the cave of St. Brélade in Jersey and in the Devil’s Tower at Gibraltar. Their successors, the first of Homo sapiens, Men of the Aurignacian age (the early part of the Upper Old Stone Age, c.16,000 to c.11,000 B.C.), were of two main races, the tall short-faced Crô-Magnons, and the shorter Grimaldians, perhaps closely related to African bushmen (W. J. Sollas, 1924). Great auk bones have been found in Grimaldian deposits in the Grotta Romanelli in the heel of Italy^* and in another cave whose habitation goes back to the end of the Old Stone Age, El Pendo in north Spain, a wall-etching (Fig. 12) of Magdalenian age (c.8,000 B.C.) may represent a great auk (H. Breuil and others, 1911; G. Clark, 1948). It is probable that between the end of the last glaciation of the Ice Age (about 15,000 B.C. in southern Europe, about 10,000 B.C. in northern) and the present day, i.e. during the Upper Old Stone, Middle Stone, New Stone, and Iron Ages the great auk had quite a wide distribution; judging by the number of bones, and the presence of the bones of young, in some prehistoric kitchen-middens in Britain and western Scandinavia, its breeding-range was possibly wider than it was found to be in historical times (Gulf of СКАЧАТЬ