The reason in 1884 for the contrary of the usual rule, viz., that East Coast stations of Isle of May and Bell Rock usually giving heavier returns than the West Coast stations S. of Clyde, is not far to seek for. The heaviest rushes at Isle of Man, and all down the West Coast S. of Clyde, occurred between the 15th to 21st and 26th October (see under [Chickens Rock] especially), while at Isle of May, Firth of Forth, no great movements of birds were visible. The winds on East Coast of Scotland were N. and E., and rarely W., but at Isle of Man and West Coast southerly and westerly. The migration on East Coast was pressed down on to the East English Coast by northerly winds. But on the West Coast birds travelled with light arid most favourable winds, concentrating their forces at the central and commanding stations of the Isle of Man. We regret we have no returns from the other Isle of Man stations. I hope the men are not disheartened by the non-appearance for two years of the West Coast of England Report which was entrusted to Mr. Philip M. Kermode. We earnestly hope they will now continue to send in schedules, the Isle of Man stations being most important.
The rapid increase of the Stock Dove in South and Central Scotland is very remarkable. They appeared commonly in East Stirlingshire in 1884-85, and have been nesting for some years in the Vale of Menteith, one of the high roads of migration. Many crossed the North Sea this past season to the East English coasts. Migration undoubtedly has a great influence upon extension of range, and the process seems easy to trace out; and it is very interesting also to find a similar extension of the Stock Dove to the rabbit-burrows of the sandy coast of Moray of late years (auct. Rev. Dr. Gordon and Capt. Dunbar Brander).
It appears useful in this place to speak of the comparative numbers of Woodcocks in the past six years. At the conclusion of our General Remarks on the last Report (1883) we called attention to the unusually large movement of Woodcocks, and to the area which appeared to have been principally selected by them before their final departure for N. Europe. As mentioned already (Report 1883), we had very few indications of their passage over Isle of May or East Coast lighthouse stations; and all stations returning any mark them as "rare" (see Report, 1882) or "rare in spring." Pentland Skerries, Bell Rock and Isle of May in six years have only recorded amongst them an infinitesimal number of spring records, and almost always with the remark "rare."
In 1879, which was a good Woodcock year in Scotland, we have not a single lighthouse record from either W. or E. Coasts. Yet I saw nineteen killed one day near here. In 1880, no records. In 1881, no spring records and scarce in autumn. Records at Butt of Lewis, Skerryvore and Lismore. Earliest, Oct. 28th. In 1882, a few spring records, one at Isle of May, April 9th ("not remembered before at this season," J. A.) Considerable and steady records, however, in autumn at five stations, north of Pentland Skerries inclusive, and at Isle of May. Rush Oct. 20th (twenty shot at Isle of May). In 1883, one record in spring at Bell Rock, April 7th, and rare in autumn; none till October, when a few at Monach Isle, Dhuheartach, Lismore, Loch Ryan, and in November at Kyleakin and Lismore, all between 29th and 31st Oct., indicating a rush. In 1884, which was a good Woodcock season on shore, with immense spring returns visible between Firths of Forth and Clyde, yet only two spring records at Pentland Skerries and Isle of May, April 3rd and March 30th respectively. In autumn, near this, one day I saw eighteen Woodcocks killed. The similarity of circumstances of 1879 and 1880 are worth attention. A considerable number of Woodcocks were killed in October and November, 1884, at Isle of May, and indications of arrivals very general. The spring records must have been weakly birds (one was disabled), as they appeared long after the spring return rush, great numbers being observable on land on 8th, 9th, 10th to 12th March. Indeed it would almost appear that any records sent from Island- or East-Coast stations during spring were of probably maimed or weakly birds, or birds delayed long after the "return of the Woodcocks" in March. As before remarked, the spring birds were all small russet cocks, and they rested 9th, 10th, 11th and 12th March between Firths of Forth and Clyde, "lifted" again, and did not alight till they had crossed the German Ocean (see 1883 Report, pp. 80, 81). The autumn rush was considerably later than usual in 1884 (see details).
Regarding the unusually extensive migration of Gulls to our coasts in 1884-85, several suggestions as to the influencing causes are readily at hand, but the following appears to have the greatest weight and importance.
As we are informed in 'Nature,' of Feb. 12th, 1885, recent Norwegian explorations in the Spitzbergen seas show that the year 1884 was a very remarkable ice year. "The west side of Spitzbergen was blocked by a belt of land ice the whole summer through, whilst the east side, which is nearly always blocked with ice, was more open than it had been for many years. These conditions, there seems little doubt, depend on the prevailing direction of the winds."
Now, the temperature of water having been lowered by the accumulation of ice along the W. coast of Spitzbergen, which is comparatively approximate to the furthest N.E. influence of the Gulf Stream, it seems natural to suppose that a deflection of the branch of the Gulf Stream, caused by the colder Arctic ice and current, the accumulation of which former was caused by the prevailing N. and E. winds on the Arctic Seas, would reach round past the S. end of Spitzbergen to the East Coast, and would cause the unusually open sea there. But the main channel of the Gulf Stream would still be towards the S.W., and would afford the natural outlet for all manner of ocean life, which requires certain temperatures; and which, such as Entomostraca, Copepods, Molluscan larvæ, &c., afford food to other higher organisms.
The great quantity of such food which in ordinary summers and autumns accumulate around the shores of Spitzbergen, or in the warm shallow summer seas off the N. coast of Europe, no doubt retire to deeper water on the approach of winter. In unusually cold seasons the retreat is continued, following the course of the milder Gulf Stream until more temperate seas are reached.
In the course of its retreat it is discovered by vast shoals of fish, which pursue these minute forms of life even to the uttermost limits of its possible extension, up certain firths arid inlets of our East Coast of Scotland. Naturally also the last link of the migratory chain is taken up by the enormous population of Gulls and other species of sea-fowl, as we know has been the case in the winter of 1884-5 in the Firth of Forth.
In the log of the steam whaler 'Eclipse,' Captain D. Gray (see Report, antea, [p. 7]) in summer, repeated mention is made of the unusual abundance of "whale food" in the Spitzbergen seas, and I am indebted also to Captain Gray, through Mr. Thomas Southwell, of Norwich, for a return of sea-temperatures of the same seas.