DUNLIN.
Owing to the great seasonal changes of plumage which this Sandpiper—the Tringa alpina of most naturalists—undergoes, considerable confusion has prevailed concerning it. Linnæus described birds of this species in summer plumage as distinct from individuals in winter plumage, naming them alpina and cinclus; but Temminck (and before him B. Meyer) with greater discernment united both under the name of T. variabilis. Birds in the two plumages have also received distinctive colloquial names; in summer dress, the bird is known as “Dunlin,” in winter dress as the “Purre.” Other local names of wide application to this species are “Ox-bird,” “Stint,” and “Plover’s Page,” the latter being derived from the habit of the Dunlin to accompany a Golden Plover, flying to and fro over the moors, where the two species chance to be nesting. Perhaps the Wryneck has in like manner, gained the name of “Cuckoo’s Mate” from its habit of flying in attendance with that bird; although some writers attribute the term to the fact of the two species appearing in our country about the same time.
The Dunlin is absolutely the commonest Limicoline bird of the shore, and certainly the most widely dispersed. It possesses the habit, in common with so many other species of this order, of retiring to moors to breed; but as soon as nesting duties are done it returns to the coast, and for the remainder of the year continues to reside upon it. The Dunlins that breed in our islands represent but a very small portion of the vast number that winter on the British coasts. The majority of these are from more northern haunts, winter migrants, that haste away again with the return of spring. During its residence on the coast the Dunlin is remarkably gregarious, assembling often in flocks of thousands, which, by preference seek such portions of the shore as are low-lying and muddy. Salt-marshes, slob-lands, estuaries and creeks, and vast expanses of mud—as the Wash for instance, are the favourite haunts of the Dunlin. These large flocks of Dunlins are much more difficult to approach than smaller gatherings or individual birds. Dunlins are active little birds, almost incessantly in motion, running daintily about the muds, by the margin of the waves, or wading through the shallow tide pools. During the course of feeding a large flock will become widely scattered, and it is remarkable how quickly the broken ranks reform. There are few sights so pretty along the salt-marshes and mud-flats than a large flock of Dunlins, in the act of performing those graceful aerial movements so characteristic of this little bird during its winter sojourn upon the coast. The whole flock, as with a single impulse, will spread out like a net, close up again, apparently vanish, appear black, or like a flash of silver, just as the birds turn and expose their dark or white plumage to the light. Sometimes the flock will head straight away down the coast, passing the observer with a rush and whirr of wings, and a chorus of purring cries; at other times a large flock will rise en masse from the muds, pass out to sea a little way, turn, and go some distance along the shore, come back again, repeating the movement time after time, ever and anon appearing as though about to alight, dipping and rising with marvellous regularity. No doubt these movements will recall to the observer the gyrations of the autumn flocks of Starlings, for there is much in common between the two. During its sojourn upon the coast the Dunlin feeds upon crustaceans, sand-worms, molluscs, and other small marine organisms; but in summer insects, grubs, worms, and ground-fruits are eaten. The usual note of the Dunlin is harsh, and resembles the word purr—hence one of the bird’s trivial names; during the breeding season it is a long drawn peezh. In the pairing season, when the male indulges in certain aerial gambols, he utters a trill, which has been likened by some observers to the continuous ringing of a small bell.
It is a rather remarkable fact that the Dunlin is the only species of Tringa that nests in the British Islands. It breeds sparingly and locally in Cornwall, Devon, and Somerset, perhaps in Wales, and thence northwards, more generally, over the remainder of England, and in Scotland up to the Shetlands. Dunlins begin to move from the coasts in March and April, and to resort to their breeding places, which are situated on the marshy moorlands and mountain swamps, often at no great distance from the sea, or at least from tidal waters. The nest is a mere depression, often in a tussock of grass or rushes, or beneath a small bush, or even in a patch of thrift on bare sandy soil, lined with a few scraps of withered vegetation, or enclosed with a few twigs or roots. The four pyriform eggs are pale olive or pale brown, blotched and spotted with reddish- and blackish-brown and gray. We remark the same extraordinary difference between summer and winter plumage, as we have already observed in the Knot and some others. In summer or breeding plumage, the Dunlin is rich reddish-brown above, striped with dark brown; lower breast or gorget, deep black; remainder of under parts white. In winter the upper parts are chiefly ash-gray, and the under parts white, except the gorget, which is now grayish-brown. Outside the British Islands the Dunlin has a very wide distribution, breeding not only in the Arctic regions of both hemispheres, but in many temperate latitudes of the same; in winter it is dispersed over North Africa, Southern Asia, the Southern States of America, and the West Indies. At Heligoland, flocks of Dunlins invariably indicate bad weather.