British Sea Birds

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Charles Dixon. British Sea Birds

CHAPTER I. GULLS AND TERNS

CHAPTER II. PLOVERS AND SANDPIPERS

CHAPTER III. GUILLEMOTS, RAZORBILL, AND PUFFIN

CHAPTER IV. DIVERS, GREBES, AND CORMORANTS

CHAPTER V. DUCKS, GEESE, AND SWANS

CHAPTER VI. PETRELS

CHAPTER VII. LITTORAL LAND BIRDS

CHAPTER VIII. MIGRATION ON THE COAST

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In the present chapter we commence the study of an entirely different class of birds. The Gulls are for the most part seen flying in the air or swimming upon the sea, but the Plovers and the Sandpipers spend the greater part of their time on the ground. Again, Gulls, when adult, are remarkably showy birds, but the Plovers and allied species are just as inconspicuous. Many of the haunts frequented by Gulls are utterly unsuited to the Plovers and Sandpipers. These principally delight in low sandy coasts, mud-flats, slob-lands, and salt marshes. Rocks and ranges of cliff have no attraction for these little feathered runners of the shore; they obtain their food on the shallow margin of the sea, on the sand and shingle, the mud and the ooze, or at low water among the weed-draped stones. They are emphatically beach birds. Such parts of the coast that have little or no beach uncovered at high water, on which they may rest whilst the tide is turning, or at low water on which they can seek for food, are but little frequented by these Limicoline birds. Consequently we find them much more abundant on the flat eastern coasts of England, and some parts of the southern coasts, with their miles of sand and mud and wide estuaries, than on the much more rock-bound north and west.

The Plovers, with their allied forms, the Sandpipers and Snipes, and between which no very pronounced distinction is known to exist, constitute a well-defined group of birds, perhaps on the one hand most closely allied to the Gulls, and on the other hand to the Bustards. There are more than two hundred species in this group, distributed over most parts of the world. The Limicolæ (under which term we include the Plovers, Sandpipers, and their allies) present considerable diversity in the colour of their plumage, and in a great many species this colour varies to an astonishing degree with the season. The most brilliant hues are assumed just prior to the breeding season; the winter plumage is much less conspicuous. To a great extent this colour is protective, the brighter plumage of summer in many species harmonising with the inland haunts the birds then frequent: the duller hues characteristic of winter assimilating with the barer ground – the sands and mud-flats. It is worthy of remark that the species which do not present this great diversity in their seasonable change of plumage – such as the Snipes and Woodcocks – confine themselves to haunts clothed with vegetation all the year round; or – as in the case of the Ringed Plovers – to bare sands and shingles. In their moulting the Limicolæ are most interesting. It is impossible to enter very fully into the details of this function in the present volume, nor is it necessary, for the purpose of this study of marine bird-life, to do so. A few of the most salient facts, however, may be mentioned. The young of all Limicoline birds are hatched covered with down, and are able to run soon after their breaking from the shell. They consequently spend little time in the nest, after they are hatched. This down varies considerably not only in the pattern of the colour, but in the colour itself. Some of these chicks, or young in down, are beautifully striped or spotted; others are sprinkled or dusted with darker or lighter tints than the general colour. In all, however, the colours are eminently protective ones, and harmonise so closely with the hues of surrounding objects that discovery is difficult; more especially so as the chicks possess the habit of crouching motionless to the ground when menaced by danger. The first plumage of the young bird in the present order, approaches more or less closely in colour that of the summer plumage of the adult. At the beginning of autumn, however, these bright colours begin to be changed for a dress which resembles the winter plumage of their parents. This is not effected, however, by a moult, but by a change in colour of the feathers, only the very worn and abraded ones being actually replaced. In the spring following, these immature birds moult into summer plumage, similar to that of the adults, although the wing coverts retain their hue, characteristic of summer or the breeding season, until the next autumn, when for the first time these feathers are changed for the gray or brown ones of winter. It should here be remarked that the wing coverts of the adults seem only to be moulted in the autumn, so that this portion of their plumage is always the same colour after the bird reaches the adult stage of its existence. The phenomenon of the alteration of colour in the plumage of birds, and especially in Limicoline species, without moulting or an absolute change of the feathers, is a profoundly interesting one. One of the most remarkable facts in connection with this phenomenon is the restoration of the worn and ragged margins of the feathers in some Limicoline species to a perfect condition without a change or moult of the notched and damaged feather. Schlegel was the first naturalist, apparently, to discover that this wonderful renovation took place, but his statements seem to have been doubted by naturalists. Fortunately Schlegel’s opinions have been fully confirmed by Herr Gätke; and the reader interested in the subject is referred to that great naturalist’s remarks thereon in his book on the birds of Heligoland.1 This seasonal change of colour may be produced both by a moult and by actual transition, without cast of feather, even in the same bird: the restoration of ragged feathers and development of colour upon them may also be progressing at the same time. Thus the black markings on the head and neck of the Golden Plover are the result of colour alteration, but the black on the breast is attained by moult. The colour changes in the Sanderling, the Knot, the Dunlin, the Redshank, and numerous other allied birds, are perfectly astonishing: in the Redshank especially so, the profusely barred upper plumage being developed without change of feather, and the feathers reacquiring a pristine freshness and perfectness which seem almost incredible without a complete moult!

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Although the Ringed Plover appears only to rear one brood in the year, its laying season is prolonged from the middle of April to the beginning of June. Early in April the winter flocks begin to disband, and the birds to disperse over their breeding places. Many pairs may be found breeding on one large stretch of sand in a suitable district. Some individuals seek an inland site for their eggs, on the bank of a stream or lake, but the majority prefer the sands of the sea-shore. Occasionally the nest has been discovered remote from water. This Plover makes no nest. The eggs sometimes are laid in a hollow of the sand, but just as frequently on the level surface. The fine sand is always preferred to the shingle, as the eggs best harmonize in appearance with it, their fine markings becoming more conspicuous on the coarser surface. The bird sits lightly: indeed it is most exceptional to see one rise from its eggs, unless the spot had been previously marked. When disturbed, the birds exhibit but little outward manifestation of alarm. They may be seen running to and fro about the sand, but their behaviour is very different from that of the Lesser Terns, which often nest on the same sands. The eggs of the Ringed Plover are always four in number, very pyriform in shape, and invariably laid with the pointed ends turned inwards. They are large in proportion to the bird, and pale buff or stone colour sparingly spotted and speckled with blackish-brown and ink-gray. During May and June a smaller and darker race of Ringed Plover passes along our coasts, to breed further north; appearing on the return journey during August, September, and October. There is some evidence to suggest that this race breeds sparingly on the coasts of Kent and Sussex.

The Kentish Plover rears but one brood during the summer, and preparations are made for this towards the end of May. It is not improbable that this Plover pairs for life, seeing that the same localities are visited year by year for nesting purposes. It makes no nest, the eggs being laid in a little hollow amongst the coarser sand or the shingle, or on a drift of dry seaweed and other shore débris. The eggs are usually three, but occasionally four in number, and are pale or dark buff in ground colour, blotched, scratched, and spotted with blackish-brown and slate-gray. As is the almost invariable custom with birds breeding on bare plains and beaches – and whose eggs are protectively coloured – the Kentish Plover sits lightly, rises from her eggs as soon as danger is discovered, and evinces but little outward anxiety for their safety; although, in some instances, the feigning of lameness has been resorted to, especially when the eggs have been on the point of hatching. The young birds and their parents form a family party during the autumn, and apparently migrate southwards in close company.

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