Watching birds in winter

In the bird-watcher's year, there are two distinct periods which are marked more or less clearly by the two equinoxes. From March to September he is concerned mainly with the coming and going of the summer migrants and with the breeding phase of these and the resident birds. During the other six months of the year, from September to March, the winter migrants to this country occupy his attention, together with varied aspects of the behavior of those resident species which remain to face our climate in winter. Not that any hard and fast divisions are possible, for a continuous overlapping of birds of many classes occurs, with winter visitors still with us in the spring, when the first summer migrants come in, and, at the other end, a great many summer migrants still here when the first of the winter birds appear in late summer. On the east coast of England it is possible to witness a considerable influx of birds, especially of the wader class, as early as the first two weeks of August, when some of the swallow and martins will have second or third broods of young still in the nest. Curlew, golden and green plover, and knot, dunlin and turnstone, as well as many others, arrive from overseas in considerable flocks, some of which may begin to appear in late July. This fact, of course, is well known, and many watchers have recorded the dates of arrival of such birds with meticulous care. But the far more important point, about whether these early migrants are adult birds, or young birds of the year, has not been carefully studied, yet it merits considerable attention. We know that in some species the adult birds leave the country in which they have nested, before the young birds which they have bred, and that these latter are left to find their way to the winter quarters unaided and alone. On the other hand, with some species the young tend to start their autumn migrations in advance of the adult birds, and many of the flocks of lapwings which cross the North Sea from the Continent in early August are composed entirely of birds of the year. Yet another variation is shown by the geese, which tend to keep together in family parties and migrate in flocks which are aggregates of several such parties. With the various species of duck, the drakes migrate first, as soon as they are fairly over the "eclipse" molt, and are followed later by the ducks and young birds. There is scope for careful study here, for provided the student can be certain of identifying the immature bird from the adults in winter plumage, he should be able to record the order of arrival of the birds, and thus work out to which category any one species belongs. Young lapwings can be readily distinguished from the adults, and it is fairly certain that with these birds most of the young migrate in advance of their parents. With knots, the reverse appears to be true, for adult birds still retaining much of the red which characterizes their breeding plumage, may be seen on the East coast mud-flats in the first week of August, before any of the young put in an appearance.