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British Sea Birds
By the end of April most of the adult Common Gulls have left all our southern coasts and retired northwards to their breeding places. As these are visited yearly in succession, it is not improbable that this Gull pairs for life. Its nest colonies are situated both inland and on the coast. An island in a mountain lake, the marshy shore of a loch, the flat table-like summit of a rock stack, or the rolling grassy downs near the open sea, in little populated districts, may be chosen; but so far as my experience with this Gull extends, I have found the favourite site to be rocky islands in quiet secluded sea-lochs. These colonies of Common Gulls vary a good deal in size; and in some districts, perhaps where suitable sites are scarce, the bird breeds in scattered pairs only. The eggs are laid during the last half of May and the first half of June; only one brood is reared in the season, but if the first eggs are taken they are generally replaced. The nest of this Gull varies much in size; some structures are mere hollows lined with a tuft or two of grass; others are more elaborate, composed of heather stems, pieces of turf, sea-weed, and stalks of marine plants, lined with finer grass, often gathered green. They are built indiscriminately amongst the long herbage, in hollows and crevices of rocks, or on ledges of the bare cliffs. In Norway the eggs of this Gull have been taken from the deserted nest of a Hooded Crow, in a pine tree, but no instances of a similar character have occurred, so far as is known, in our islands. The Common Gull usually lays three eggs, but instances of four are not rare. They run from olive-brown to buffish-brown in ground colour, spotted and often streaked with darker brown and brownish-gray. The eggs of this Gull are extremely good eating. One often wonders why they are not gathered for the table, just as much as those of the Lapwing.
KITTIWAKEThis charming Gull, the Larus tridactylus of scientists, so named from its entirely absent or rudimentary hind toe, is one of the best known, as it is one of the most widely distributed, British species. These remarks are however most applicable to the non-breeding season; for during the nesting time it is rather more local, owing to the conditions under which its young are reared. The Kittiwake very closely resembles the Common Gull in general appearance, but the mantle is paler, the legs and feet are dark brown, and the primaries, or longest feathers of the wings, have broad black tips: it is also a perceptibly smaller bird, the smallest in fact of the typically marine Gulls. Of all the British Gulls the Kittiwake is certainly the most maritime in its habits, and is never known to visit inland districts, unless driven from the coast by storms of exceptional violence. Save in the breeding season it may be met with on all the low-lying coasts, visiting harbours, bays, and fishing villages, and imbuing many a littoral scene with life. The Kittiwake is a much more oceanic bird than the Common Gull, and often wanders immense distances from land in quest of food. It is said that birds of this species have been known to follow vessels across the North Atlantic, but this seems almost incredible – not because the bird is physically unable to perform the feat, but because we can scarcely believe any bird would wander of its own free-will so far from the local centre of its habitat. One of the most striking characteristics of the Kittiwake is its peculiar cry, heard to the best advantage at the nesting places. This note, from which the colloquial name of the species is derived, resembles the syllables kitty-a-ake, requiring but little play upon the imagination to render as get-a-way-ah-get-away. It is only during the breeding season that this cry is heard to perfection, and after that is over the bird becomes a singularly silent one. The flight of this Gull is light and buoyant, but powerful and often long sustained. The bird may often be observed fishing at no great distance from shore, flying to and fro every now and then, poising and hovering previous to pouncing down upon a fish or other floating object. It is also an adept swimmer, and very frequently sleeps whilst sitting on the waves. The Kittiwake is perhaps more exclusively a fish-feeder than any other British Gull. It seldom searches for food on shore, and does not exhibit those omnivorous tastes that characterise so many of its congeners. It is a persistent follower of fish shoals, especially herrings and sprats, and will remain in the company of fishing fleets for weeks together. A scrap of food thrown from a ship will speedily be seized by one of these birds; whilst a few crustaceans and other marine creatures are taken from time to time.
The Kittiwake is a rather late breeder. It most probably pairs for life, as the same nesting places are resorted to each season. Of all the Gulls none breed in more inaccessible situations. The nests are almost always built upon a beetling ocean cliff, against which the waves are for ever beating in ceaseless strife. Except during the three months or so of the breeding season, this Gull is seldom seen at its nesting sites. In April or May the birds collect at their various stations, never quite to leave them again until the young are able to fly. It is a very gregarious bird, and some of these “gulleries” are very extensive, containing many thousands of pairs. In some localities, however, where the accommodation is either limited or unsuitable, but a few birds congregate to form a colony. The nests, often made as close together as they can be wedged, are built upon the ledges, shelves, and prominences of the rocks. Favourite spots are where the cliffs overhang, or at the entrance of a cave or hollow in the precipice. They are made at varying heights on the cliff, tier above tier, the lowest often within a few feet of high-water mark, but the most crowded places are usually about midway up from the sea. The nests are large and well made, many of them apparently the accumulation of years, composed externally of turf and roots, with much of the soil attached, and caked together. Upon this foundation a further nest of sea-weed and the stalks of various plants is formed, finally lined with finer and dry grass, and sometimes a few feathers. The nests and the cliffs in their vicinity are thickly whitewashed with the droppings of the birds. The eggs are two or three in number, rarely four, and vary from greenish-blue, through pale buff and buffish-brown to brownish-olive, blotched and spotted with reddish-brown, paler brown, and gray. No words of mine can adequately describe the beauty and animation of a colony of Kittiwakes. Their cries are deafening, and when the frightened birds flutter from the cliffs, and pass to and fro in thousands like a living snowstorm, the effect, whether seen from the water or from the cliffs above is charming in the extreme. It is sad to think that such a spot should too often become a scene of slaughter. But such is the case; the poor birds breeding too late fully to profit by the protection afforded by law. Vast numbers of this pretty gentle Gull are killed yearly, for the sake of their plumage. Even when the breeding places are left, the poor birds are shot in thousands out at sea. The Kittiwake is the most trustful perhaps of the Gulls, and a flock will remain hovering round a boat until almost decimated by the gunners. The young Kittiwake is widely known along the coast under the name of “Tarrock.”
BLACK-HEADED GULLIn most inland districts frequented by this Gull (the Larus ridibundus of Linnæus) it is known as the “Peewit,” the “Peewit Gull,” or the “Laughing Gull.” It is not only one of the most widely distributed but one of the best known of our sea birds. And yet to describe the Black-headed Gull as a “sea” bird in the sense we have hitherto used the term is, to say the least, somewhat misleading. This species belongs to a small group which might more appropriately be termed “marsh” Gulls. It is almost as much seen in certain inland localities as it is in marine ones; whilst in many of its habits it bears a close resemblance to the Rook – feeding on the pastures, following the plough, and perching regularly in trees. During spring and summer many of these Gulls resort to inland haunts to breed – as for instance at Scoulton Mere in Norfolk, Twigmoor in Lincolnshire, and Aqualate Mere in Staffordshire – and from these centres visit the surrounding country for miles, in quest of food. Slob-lands and low muddy coasts are favourite haunts of this Gull, but during the non-breeding season it may be met with on almost all parts of the coast. In winter it often wanders up the larger tidal rivers for miles; and the Gulls that visited the Thames in such abundance during recent winters, were principally of this species, doubtless from Norfolk and Essex. Many of these Gulls appear to pass our southern coasts, especially in spring, and I have remarked them again in great plenty during the sprat season in late autumn. I may in addition state that this migration has been observed along the coast of South Devon, the nearest breeding station being near Poole in Dorset. The birds linger about Tor Bay in spring until, in many cases, the full breeding plumage – the sooty-brown head – is assumed.
Owing to the great diversity of its haunts the Black-headed Gull is almost omnivorous in its diet. Inland it feeds on grubs – especially wire-worms – insects, worms, fresh-water fish, and newly sown grain, as I have often ascertained by dissection; on the sea coast it subsists on fish, crustaceans, and various odds and ends obtained about harbours or vessels. It seeks its food both whilst swimming about the water, fluttering above it, or when walking on the shore. This Gull is much more Tern-like in its habits than the larger species we have already dealt with. Of its services to the agriculturist there can be no question; it is just as useful on the land as the Rook, without that bird’s few little pilfering ways.
The Black-headed Gull is an inland breeding species, and resorts to marshes, wet moors, and meres, at varying distances from the sea. Sometimes these breeding-places are in fairly well-timbered districts, and often surrounded by trees and bushes. This Gull, too, is remarkably gregarious during the breeding season, and some of its colonies are very extensive, consisting of many thousands of pairs. The “gulleries” are visited for nesting purposes in March or April, and as the birds return to the same spots year after year, they probably pair for life. Nesting begins in April. Most of the nests are made upon the ground in rush tufts, in hassocks of coarse grass and sedge, amongst reeds in shallow water, on masses of the previous year’s decayed aquatic vegetation, or on the flat, spongy, moss-covered ground. Odd nests are occasionally made in the trees and bushes, or even on boat-houses. Many of the nests can only be described as mere rounded hollows in the cushions of grass or sedge; the more elaborate structures are usually in the wettest situations, and these latter are often added to as incubation advances, either to replace the wear and tear from the incessant wash of the water, or to provide a sufficiently large platform on which the young may rest. The nests are made of bits of reed and rush, coarse grass, flags, and scraps of moss, lined with finer materials of similar description. The eggs of this Gull are usually three in number, sometimes four. They are subject to much variation, ranging from rich brown to pale bluish-green in ground colour, spotted, blotched, blurred, and streaked with several shades of brown and gray. Large numbers of these eggs are gathered for culinary purposes, the crop being systematically taken, and the birds always allowed eventually to sit upon their final clutch. Many of these eggs are passed off for those of the Peewit by unscrupulous dealers, notably in Leadenhall market. Few scenes in the bird world are prettier than a colony of Black-headed Gulls. When disturbed at their nests the birds rise in fluttering crowds, drifting noisily to and fro, anxious for the safety of their eggs or helpless young. As is the invariable rule with birds that continue to replace their taken eggs, but one brood is reared in the season.
THE SKUASThese birds may be readily distinguished, even when on the wing, by the cuneiform or wedge-shaped tail, and by the dark upper plumage. The bill is also much stouter and hooked at the point, whilst the claws are sharp and curved. Skuas are only exceptionally seen by the ordinary visitor to the sea-side. In the first place, they only breed in our islands in the extreme north or west of Scotland, and in the second place they are decidedly oceanic in their habits, after the nesting season is passed. Occasionally Skuas may be seen on migration, especially in autumn, and along our eastern and southern seaboard; occasionally they are driven shorewards by protracted stormy weather, and under these circumstances have frequently been known to visit inland localities. Odd birds are generally seen, perhaps a party of half a dozen, but on very exceptional occasions large flocks make their appearance – witness the thousands of Pomarine Skuas that visited the coast of Yorkshire during the autumns of the years 1879 and 1880.
The Skuas are birds of remarkably powerful flight, displaying marvellous command over themselves in the air, turning and twisting with great speed. These birds are the Raptors of the sea; a terror to the Gulls and Terns; merciless robbers of the hard-won spoil of more weakly species; destroyers even of the eggs and helpless young of other sea birds. All the four species of northern Skuas are visitors to the British Seas, but only two of them are indigenous to our islands. The first of these to be noticed here is the Great Skua, Stercorarius catarrhactes, one of the most local of British birds during the breeding season, as its only known nesting places in our area are on Unst and Foula, two small islands of the Shetland Group. Except during the breeding season, the Great Skua is mostly oceanic in its habitat, wandering long distances from land in quest of prey, attending vessels and fishing fleets, only drawing landwards by stress of weather or unusual abundance of food. This Skua is practically omnivorous. During its summer sojourn near and on the land it repeatedly raids the colonies of other sea fowl, to prey upon exposed eggs or unguarded young; it captures the smaller Gulls, notably the Kittiwake: it also picks up any stranded fish or other carrion; and is constantly on the watch to chase any Gull or Tern that catches a fish, following the poor bird with fatal persistency until, terror stricken, it disgorges its food, which is promptly seized by the voracious Skua. The call note of this Skua is very similar to that of the Lesser Black-backed Gull, but when under the excitement of chasing other birds, or of seeking to guard its own domain, the bird utters a loud cry which is likened by many observers to the word skua or skui.
The Great Skua resorts to its breeding grounds in April, and the eggs are laid in May. As it returns yearly to the same places, it very possibly pairs for life. The nests are made upon the ground of the high moorlands, amongst the heath and grass, and are mere hollows in the moss, sometimes lined with a little dry grass. The eggs of this Skua are two in number, and vary from pale buff to dark olive-brown in ground colour, sparingly spotted and speckled with dark brown and grayish-brown. These eggs are large in size, and very closely resemble those of the Herring Gull. But one brood is reared in the year, and by the end of August the young birds and their parents desert the nesting colony, and adopt their pelagic habits. Few birds are so courageous in defence of their nests as the Skua. Even such predaceous creatures as Eagles, Ravens, and dogs are driven off; whilst human intruders are screamed at and approached within a few feet, the birds wrathfully extending their legs as if they would strike, and skimming to and fro in rage. Many tales of this bird’s daring at its nesting places are current in Shetland, where it is known almost universally as the “Bonxie.”
Our second species is Richardson’s Skua, the Stercorarius richardsoni of some systematists, the S. crepidatus of others. Although not quite so local as the preceding species, its breeding area is remarkably restricted, so far as the British Islands are concerned. It breeds on the Hebrides, in Caithness and Sutherlandshire, and on the Orkneys and Shetlands. Richardson’s Skua is a more gregarious species than its larger relative, but its habits generally are much the same. It is, for its size, equally daring and rapacious; is also remarkable for its powers of flight; but differs from the Great Skua in being more gregarious. Richardson’s Skua is for the most part a summer migrant to the British Islands, and numbers of birds pass along our coasts in spring to their northern breeding-grounds. It is only during the seasons of passage that the visitor to our southern coasts may hope to fall in with this bird, and even then it does not approach the land much. Like the other Skuas, the present species is a relentless robber of the Gulls and Terns, chasing them up and down until they disgorge their fish, and repeating the process at every opportunity. Eggs, young birds, and carrion, are also eaten. It is said to capture weakly birds, but I do not think it is so much addicted to this Hawk-like habit as the preceding species. During summer insects and ground fruits are eaten, whilst it has been known to take worms and molluscs. The note of this Skua is described either as a plaintive mee or kyow, and when in chase of a bird it has been likened to the syllable yah, oft repeated.
Richardson’s Skua reaches its breeding-grounds in the British Islands early in May. Its haunts at this season are open moors, at no great distance from the sea. Although social at its breeding-places, it can scarcely be described as gregarious, and the nests are usually scattered up and down the moorland area. This Skua appears to pair annually, and the nest, always made upon the ground, is merely a hollow, carelessly lined with a little dry herbage, and sometimes nothing but a shallow cavity in the moss. The eggs, normally, are two, but sometimes three have been found, and occasionally but one. They range from olive to brown in ground colour, spotted and speckled with darker brown and grayish brown. Incubation is performed by the female, and lasts about a month. At its breeding-places Richardson’s Skua is very demonstrative, and often reveals the situation of the nest by its anxious movements above the intruder’s head. After the young are reared the moors are deserted, and for the remainder of the year this Skua is decidedly pelagic in its habits and haunts.
We now pass to the Terns. These pretty graceful birds – widely known as “Sea Swallows” – differ in many respects from the Gulls and Skuas. They most closely resemble the former in general appearance, but may be easily distinguished by their slender form, small size, and forked tail. Of the dozen species that have been regarded as “British,” no less than five breed within the limits of our islands. The Terns are far more locally distributed than the Gulls. Many miles of coast may be traversed without one ever seeing a Tern. They are all migratory birds with us, visiting Britain in summer to breed, and retiring south again in autumn. It is only during the season of passage, therefore, that they are at all widely dispersed, for the remainder of their sojourn on our coasts is spent at or in the near vicinity of their breeding-stations. The five indigenous British species follow.
SANDWICH TERNThis fine species – the Sterna cantiaca of Gmelin, and the S. sandvicensis of Latham – is not only the largest of the indigenous British Terns, but one of the rarest. It was formerly much more widely dispersed along our coasts, but persecution has thinned its numbers, and the seaside holiday-maker has banished it from many of its old-time haunts. Special interest attaches to this bird, because it is one of the very few species that have been first made known to science from examples obtained in the British Islands. It was first discovered in 1784, at Sandwich, on the coast of Kent, and described by Latham three years later. Alas! no longer does this beautiful Tern breed in its early haunts on the Kentish coast; it has disappeared from there, as it has from many another locality, without hope of return. The most important breeding-place of this Tern, and certainly the most accessible to the majority of observers, is situated on the famous Farne Islands; even here the bird is much less common than it used to be. There are small colonies on Walney Island, in Cumberland, in the Solway district, on Loch Lomond, in the Firth of Tay, and on the coast of Elgin. Its only known breeding-station in Ireland is in Co. Mayo.
The Sandwich Tern reaches the British coasts in April or early in May. But little is seen of this species whilst on passage, for it evidently keeps some distance from shore as a rule, or passes quickly and unobserved. The smaller Terns, for instance, are commonly seen on the coast of South Devonshire in Spring and Autumn, but I cannot recall a single strong migration of the present species in that locality. This Tern is seldom or never seen at any distance from the sea. Most of its waking time is spent in the air, flying about with easy, graceful motion, in quest of its finny prey. The Sandwich Tern, however, is nothing near so graceful looking on the wing as its smaller relatives, the heavier body, broader wings, and much less acutely forked tail giving it a heavier, more cumbersome appearance. Most of its food is obtained whilst it hovers above the sea. The way in which all the Terns feed is very pretty. They poise and hover above their finny victims, and every now and then dart downwards like a stone into the water and capture a fish, fluttering up again, or remaining for a moment to swallow their capture. A flock of Terns (of any species) fishing is one of the prettiest sights imaginable. In addition to small fish the Sandwich Tern devours crustaceans of various kinds, whilst its young are fed largely upon sand-lice and beetles. The Terns are much cleaner feeders than the Gulls, and I have never known them touch carrion or refuse. I have, however, seen them pounce down upon scraps of food thrown from a vessel. The usual call-note of the Sandwich Tern is a somewhat shrill scream.
This Tern probably pairs for life, and returns regularly every season to its old-accustomed haunts to breed. These are by preference low, rocky, or sandy islands, covered with marine herbage, varied with barer patches, and with beaches of rough shingle. Similar conditions are sought on the mainland, in a secluded spot on the coast, but an island is always preferred. The Sandwich Tern is gregarious, but its colonies, with one exception, in our islands are nowhere very extensive. This one exception is at the Farne Islands, where it has been computed the birds number upwards of a thousand pairs. As the nesting-places are visited very regularly year by year this Tern probably pairs for life. I have noticed, however, that the birds shift their actual breeding ground from time to time, using several spots in succession. One year they will nest here, another year there, on the same small island perhaps, but sometimes removing en masse to another one of the group. The nests are always placed upon the ground, either amongst the sand shingle and drifted debris, a short distance from high water mark, or amongst the sea campion, thrift, and coarse grass further inland; sometimes a bare mound on the highest part of the island is selected. Many nests are made within a small area, sometimes so close together as to render walking amongst them without treading on their contents a difficult matter. The nests are slight enough, mere hollows lined with a few bits of withered herbage, and in some cases even this simple provision is neglected. The eggs, which are laid from about the middle of May to the middle of June, are generally two in number, but sometimes three. These vary from creamy-white to rich buff in ground colour, handsomely blotched and spotted with various shades of brown and gray. During the hot June days the eggs seem to require little incubation, but there are always plenty of birds about the spot, ready to rise fluttering and screaming into the air when their breeding grounds are invaded by man. But one brood is reared in the season, yet if the first clutches of eggs be lost they will be replaced.