THE BLACK-HEADED GULL (LARUS RIDIBUNDUS).
SOME MODIFICATIONS OF HABITS.
For the most part lacustrine in its nesting habits, the Black-headed Gull is yet by no means unknown as a strictly sea-shore species at the breeding season. One small colony that varies from season to season from sometimes only a dozen pairs to over a hundred pairs has bred annually for many years on one part or another of the grassy salt merses of the Solway to westwards of the Nith estuary.
One season this particular colony had its nests destroyed by a succession of high tides in May, whereupon the birds shifted over the sea-bank to a turnip field, and betwixt the rows of young turnips built fresh nests of sea-wrack brought from tide-marks, and successfully brought off their young. Such modifications of habits are of perennial interest to field ornithologists, and constitute much of the charm attached to the outdoor study of birds.
No other British Gull is so much of a land-bird as this one is, and it appears to me that it is becoming greatly more attached to the land in several respects than it was in by-past years. So far as my own experience goes, it was in the abnormally severe winter of 1878–79 that I first noted these Gulls perched in rows upon house-roofs, or alighting on the streets, or coming to the back gardens and such places for food. Previously this habit was only indulged in by an odd bird or two. Since then it has become quite an everyday thing whenever frost of a few days' duration sets in. And there can be little question that they spend far longer time nowadays upon the pasture fields and amongst the crops, instead of going away to the river-sides, estuaries, and shores, as they once did when nesting-days were over. An older generation looked upon the presence of flocks of these Gulls on far inland pastures as presaging storms and
