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CHAPTER VIII.
MIGRATION ON THE COAST

The Best Coasts for Observing Migration – Migration of Species in Present Volume – Order of Appearance of Migratory Birds – In Spring – In Autumn – Spring Migration of Birds on the Coast – The Earliest Species to Migrate – Departure of Winter Visitors – Coasting Migrants – Arrival of Summer Visitors – Duration of Spring Migration – Autumn Migration of Birds on the Coast – The Earliest Arrivals – Departure of our Summer Birds – Arrival of Shore Birds – Direction of Flight – Change in this Direction to East – The Vast Rushes of Birds across the German Ocean – The Perils of Migration – Birds at Lighthouses and Light Vessels – Netting Birds – Rare Birds

In order to make the subject of Bird-life on the Coast complete, it is necessary for us briefly to sketch the phenomenon of Migration as it may be studied on the shore. A person could select no better situation for the observation of this grand avine movement than the coast. Unfortunately, however, all coasts are not equally favoured in this respect, and unless a proper selection of locality be made, the observer in quest of information will meet with nothing but disappointment. Unquestionably the best portion of the British coast-line for the study of bird migration is that washed by the German Ocean and the English Channel. The western districts are everywhere less favourable than the eastern, due partly to their much more isolated position, and the wider extent of the frontier seas. Two reaches of the British coast deserve special mention for the numbers of migrant birds that frequent them. These are the coasts between the Humber and the Thames, and the seaboard of Hampshire, Sussex, and Kent. The observer of migration on the coast will do well to bear in mind the following facts. Many birds do not absolutely confine their flight to the indentations of the coast, but fly from one headland to another, so that on the coasts of the intervening bays but little migration may be witnessed. Headlands appear everywhere to be exceptionally favourable points for observation. Rock-bound coasts, again, are not so much frequented by migrants as those that are low-lying, or present a considerable area of beach; whilst there is some evidence to suggest that where the shore is composed of cliffs falling sheer to the water, fjords and river valleys are exceptionally favoured. During the migration period, both in spring and autumn, the early hours of morning, or the dusk of evening, will be found to reward observation best. Due regard should also be paid to the direction of the wind, and the prevailing state of the weather – a change in either being often followed by migratory movement.

A very large percentage of the birds described in the present volume are migratory, although the seasonal movements of many of the species cannot be remarked, to any great extent, by the wanderer along the coast. Such thoroughly aquatic species as the Auks, the Petrels, the Divers, and the Grebes, move south or north, according to season, some distance from the land; and it is often only by the chance of rough weather driving these birds near to the land, that we are enabled to learn that their migrations are in progress, or that certain species have once more returned to our area for their winter or summer sojourn therein. The Ducks, Geese, and Swans, are birds of migratory habits, and in certain localities much of their seasonal movements may be observed from the shore. Then, again, the Gulls and Terns, although often migrating some distance from the land, may not unfrequently be seen passing up or down the coast on passage. This is especially the case with the Black-headed Gull, and the various species of Terns. These latter birds are often seen, in spring and autumn, in flocks of varying size, flying north or south, close inshore, fishing as they go, sometimes remaining a day here or there, where food chances to be plentiful. The migrations of certain species of land birds that reside in littoral districts are also pronounced and regular, and easily remarked along the coast; the arrival and departure of Martins and Swallows being a specially interesting feature. But the most remarkable birds of all, so far as concerns migration, are those to which our second chapter is devoted, viz., the Plovers and the Sandpipers. Perhaps in this group more than in any other, the habit of migration is most strongly displayed. The journeys some of these birds undertake in spring and autumn can only be described as marvellous. The Sanderling breeds in the North Polar Basin, and in winter is found in the Malay Archipelago, in the Cape Colony, and in Patagonia; the Knot has a similar distribution in summer, but in winter visits such enormously remote localities as Australia, New Zealand, the Cape Colony, and Brazil! Well may these little birds excite exceptional feelings of interest in the observer who watches them, each recurring season, running blithely over the sands and the mud-flats, when he remembers the distances they travel.

But migration on the coast is by no means confined to the birds that habitually reside upon it. All the migratory species that dwell in inland districts must pass the coast on their annual journeys in spring and autumn. At these seasons, in suitable districts (of which we have already indicated the most favourable for observation), birds may be watched day after day, and week after week, entering our area to render summer glad with their cheerful presence, passing along our shores to yet more distant destinations, or departing in autumn for warmer lands and sunnier skies. Many of these birds, of course, enter our islands during the night, and thus escape observation; many others, it may be, pass to inland haunts by day, but without alighting upon the coast at all, flying at altitudes which render their identification, or even detection, impossible; but then there are many more, and especially in autumn, when the flight is generally far more leisurely than in spring, which crowd upon the coasts, or pass along them, within easy view of the most casual scrutiny. It may here, perhaps, be advisable to allude to the general order in which migrants usually appear upon the coast. Of course, it is utterly impossible, within the narrow limits of the present chapter, to enter very minutely into the many and intricate phenomena connected with the migration of birds. The reader anxious for further and more detailed information on this very interesting subject, may be referred to the present writer’s works upon Migration, and to that on the birds of Heligoland, by Herr Gätke.⁸ Now, as regards the actual order of appearance. In spring, the observer will almost invariably find that the adult males are in the van; the females are the next to arrive, whilst the young of the preceding summer, and the more or less weakly individuals, bring up the rear. Many of these young and sickly birds pass the summer far south of the usual breeding-grounds; so that it is by no means an uncommon thing to find individuals of certain Arctic-nesting species, frequenting the British coasts throughout that season. The presence in our area of these northern birds during summer, has not unnaturally led to the supposition that they actually breed there. In autumn the order of migration is, to some extent, reversed. At that season a few old birds of either sex are the first to arrive, sometimes preceding, and always invariably accompanying, the flights of young birds, which are then moving south. Many of these young birds start off from their birth-place almost as soon as their wings are strong enough to bear them, and individuals of certain Arctic species have been met with on our coasts with particles of the down of their nestling plumage still adhering to their feathers. The adult males come south next; the females following; and last of all come the cripples and the weakly – the individuals that have been retarded in their flight by accidents of various kinds, such as the loss of wing feathers, by deformities, or by disease. The observer on the coast will also remark considerable diversity in the social or gregarious tendencies of these migrants. Some migrate gregariously in numbers that are as uncountable as the pebbles on the shore; others journey in family parties, in small flocks, or even singly. The migration of each species is usually first remarked by the appearance of an odd bird or two; then the numbers increase, perhaps with two or more great rushes when the flight of that particular species becomes exceptionally marked, the migration then gradually falling off almost, if not quite, as imperceptibly as it commenced.

We now propose briefly to sketch a few of the more salient features of migration on the coast, during spring and autumn. If the weather be favourable, the spring migration of some birds commences in February. The species moving at that early date are birds that we have in the British Isles all the year round, such as Thrushes, Hedge Sparrows, Titmice, Wrens, Finches, Buntings, Jays, Rooks, and Carrion Crows. The difficulty in distinguishing migrating individuals of these species from others that are sedentary, is sufficiently great to render the movement unseen, except, perhaps, to experts, or to the keepers of light vessels off the coast. The observations of these men, however, prove that these birds actually pass from our islands to the Continent from that date onwards. These birds all migrate nearly due east. The next birds to leave their winter quarters in Britain are those whose line of migration extends north-east, and amongst these we must include such familiar species as Blackbirds, Robins, Goldcrests, Greenfinches, Chaffinches, Starlings, Hooded Crows, Jackdaws, Ring Doves, and Lapwings. For quite a couple of months these species continue to leave us for Continental breeding-grounds, and their presence on the coast, during early spring, is an unfailing sign of their departure. Then comes the departure of such birds that are found only in winter in the British Islands – Redwings, Fieldfares, Bramblings, Siskins, Snow Buntings, and so on. The departure of these birds begins in February, or early March, and lasts until the beginning of May. About the same time, also, many coast birds pass from our islands, such as Golden Plovers, Lapwings, Curlews, Redshanks, Woodcocks, and Snipes – that is to say, the migratory individuals of these species that only visit us during winter. Ducks and Geese also begin to move north, and many indications of their passage may be seen by the careful observer of birds along the shore. March, April, and May, the two former months especially, is the period of their departure. At this season, also, many individuals of these species pass along our coast districts from more southern countries, on their way to northern haunts. These birds are known as coasting migrants. The most typical of these coasting migrants, and those that may be readily distinguished, are such species as Whimbrels, Ringed Plovers, Sanderlings, Stints, Skuas, and Curlew Sandpipers. Whimbrels are very regular in their appearance, arriving at the end of April, and the migration continuing through May.

Early in March, on our southern coasts, the purely summer visitors begin to be seen, Woodcocks and Pied Wagtails, amongst others, making their appearance. Towards the end of March, or very early in April, the first of the purely southern species reach us. Two of the most familiar are the Wheatear and the Chiffchaff; Ring Ouzels, Willow Wrens, and Yellow Wagtails follow them closely. As April passes on, the numbers of our summer migrants increase; Whinchats, Redstarts, Wrynecks, Cuckoos, Whitethroats, Blackcaps, Swallows, Martins, and so on, appearing in force. Towards the end of the month, and in May, Terns, various Sandpipers, Turtle Doves, and Quails, may all be found upon the coasts on their spring migration. Among the last to appear are such species as Lesser Whitethroats, Spotted Fly Catchers, Garden Warblers, and Red-backed Shrikes. This spring migration of birds along the British coasts lasts for a period of quite four months – from February to the end of May, or the first week in June. Some birds may be observed on passage almost throughout this period; others not more than half this time – especially the Warblers, Wagtails, and Pipits – others, yet again, complete their migration in a month or less, amongst these being the Red-backed Shrike and the Greenshank. For the spring migration of such species that visit the British Islands to breed, the southern coasts, of course, are the best points of observation – none of these birds breed south of their point of entrance to our area, as they all reach us from winter quarters in more southerly latitudes than ours.

The spring migration of birds over the British Islands has scarcely ceased, before the first signs of the autumn flight begin to be apparent along the coast. Of course, this early autumn migration is first noticeable upon our northern and eastern coast-lines. Certainly, by the middle of July, a few of the Arctic wading birds may be noticed on the shore, or flying south along the coast. Towards the end of the month, and early in August, the number of these returning migrants increases. Young Knots and Gray Plovers, with odd adult birds, appear upon the sands and mudflats. Almost at the same time we may notice the Common Sandpiper back again upon the shore, followed by Lapwings, Ringed Plovers, Greenshanks, and Curlews. Then various small birds begin to drift along the coast, on their passage south – Swifts, Wheatears, Willow Wrens, and Whinchats. Throughout August the migration of birds gets stronger and stronger, and towards the end of the month, and early in September, our own summer migrants begin to leave the country. Warblers and Swallows, Wheatears, Flycatchers, Thrushes, Wagtails, and Pipits, may be met with from time to time, along the coast, all bent upon early departure. The wide reaches of mud and sand, often so dull and uninteresting, and devoid of bird-life, in summer, are rapidly filling with a new population, Plovers and Sandpipers appearing upon them from day to day in ever-increasing numbers, whilst the seas near by are becoming sprinkled with the earliest hosts of Ducks and Geese. The Terns, once more, are on the move, this time flying south to warmer seas. With the advent of October, most of our summer birds have gone, a few belated Swallows and Wheatears, a few venturesome Chiffchaffs and Wagtails, being all that remain. All the autumn through, however, coasting migrants of many species – the same that passed north in spring – continue flying south. Most of this migration is from the north and north-east.

Early in October, however, the direction of this great migrant tide falls nearly to due east, and from this time onwards, the English shores of the German Ocean, say from Yorkshire to the estuary of the Thames, become by far the most interesting of all our coast-line to the student of Migration. Normally the number of species is not very extensive, but the number of individual birds can only be described as stupendous. The vast feathery tides of migrants that break in countless waves upon our eastern coasts in autumn, are composed of birds that breed in continental Europe and Western Asia, and return to the British Islands – the centre of their dispersal – to winter. The mighty inrush of birds must be seen to be properly appreciated. For days, for weeks, the wild North Sea is swept by these migrating myriads. By day, by night, the feathered hosts pour in; the bulk of the migrants being composed of such birds as Starlings, Larks, Goldcrests, Thrushes, Finches, Rooks, and Crows. Some idea of their numbers may be gained from the fact that these waves of birds often strike our coast-line simultaneously, north to south, for hundreds of miles. Waves of Goldcrests have extended from the Faröes to the English Channel; Larks for weeks have poured in, in successive waves, by day and night. The Hooded Crow is another species that crosses the North Sea in myriads every autumn. This bird prefers to migrate by day, and appears to do the journey across in an astonishing short time. Starlings, again, often migrate across in a succession of clouds, which defy all attempts to estimate their numbers. This migration of birds, say, on the coasts of Lincolnshire and Norfolk, is one of the most fascinating sights the shore can yield. To be out by dawn on the crisp October mornings, and to watch the vast inrush of birds to the English coast for hour after hour, is a treat no lover of birds can fail to appreciate. Here and there the sea-banks and the rough saltings are strewn with birds skulking and resting amongst the grass, or in the hedges, that have made the passage of the North Sea during the previous night, and are soon about to pass inland. Tired Woodcocks rise reluctantly from the dry grass in the hedge bottoms; Hooded Crows, in companies, are hungrily feeding on the mud-flats; Goldcrests, perhaps, are swarming on the thorn-bushes. Overhead, Sky Larks are arriving in countless numbers from over the sea, often breaking out into gladsome song as soon as the welcome land is reached; whilst Rooks, Ring Doves, Jackdaws, and Finches of various species, arrive from time to time. This state of things continues through October, and well into November, the steady influx of birds from time to time culminating in an overwhelming rush. It should also be remarked that in some years birds are more numerous than others, and the duration of the migration of any particular species varies a good deal, sometimes lasting but a few weeks, sometimes as many months. The autumn migration of birds lasts for about five months, beginning in July, and continuing to November. Of the two seasons of passage, perhaps the autumn movement will prove the most interesting to the ordinary observer of bird-life on the coast. Birds are much more numerous in autumn, and travel slower. The movements of birds during winter along the coast, are also intensely interesting, but this scarcely comes within the scope of the present chapter.

We cannot well conclude this brief account of Bird Migration on the coast without some allusion to those perils which beset the birds on their journeys, and which arise principally from light-houses and light-vessels. Vast numbers of birds kill themselves every spring and autumn by striking against these gleaming beacons of the coast. From this great mortality, however, naturalists have learnt much concerning the annual movements of birds; for the records kept by our light men, extending, as they do, over a number of years, of these fatalities and periodical visits of migrants, are most instructive and suggestive. Some of the scenes witnessed at these light-houses and vessels, during the seasons of migration – especially in autumn – are intensely interesting. These beacons are most fatal during cloudy weather; few birds strike on clear and cloudless nights. Odd birds are continually striking against the lanterns. Now and then, however, there come nights when birds swarm like bees round the lamps, and kill themselves in thousands by striking against the glass, sometimes with such force as to shatter it to fragments. The illustration at the head of the present chapter also shows another peril of migration. Many nets are placed on the shores of the Wash, and great numbers of birds are, or used to be, caught during the autumn months. Information, however, has recently reached me that the birds are learning, by many years’ experience, to avoid these snares, flying over instead of through them, and that nothing like the numbers are caught nowadays. Fifteen years ago thousands of birds must have been taken in these nets.

Another peril of migration is the danger of losing the way. Many young and inexperienced birds go astray each autumn, and the British list contains the names of numbers of rare species that have visited us on abnormal flights. Many of these birds have been captured on the coast. From Eastern Europe, from Siberia, from Africa, and even from America, these wanderers have come. Each period of migration, the observer, on the coast, may be agreeably surprised to meet with one of these lost and wandering individuals; and it is this glorious uncertainty that adds considerably to the pleasure of a ramble along the shore in spring and autumn.