Gannet, Sula bassana.—At Sumburgh Head, July 20th (earliest date), great numbers, adult and young, flying in all directions, feeding on herrings. At Pentland Skerries, July 19th, 30-40, flying E., wind N.E., 9 a.m. to 5 p.m.; 20th, 50, flying E., wind fresh N., 9 a.m. to 5 p.m.; 21st, 60, flying E., wind light N.E., clear, 9 a.m. to 5 p.m.; 22nd, 25, flying E., wind light N.E. airs, 9 a.m. to 5 p.m.; 23rd, 25-30, flying E., wind E., 10 a.m. to 4 p.m.; 24th, 40, flying E., wind S.E., 9 a.m. to 7 p.m., fog, haze; 26th, 60, flying E., wind mod. E., 9 a.m. to 7 p.m., fog, haze; Aug. 4th, continuous flights, wind light E., 9 a.m. to 7 p.m., fog, haze; 5th, continuous flights, wind moderate W., 4.30 a.m. to 8.30 p.m.
Note.—Solan Geese were observed daily in flocks going E., from July 19th to middle of Sept.; and going W. on Aug. 19th, 20th, and 25th. About the middle of Sept. young appeared amongst them. This note summarises to a great extent the above data. At Tarbat Ness, Oct. 18th, 19th, and 20th, great numbers flying N., wind S., 8 a.m. to 4 p.m. Since the return of the schedules Mr. Jack has written to me that—"On the 5th February, 1881, the Bell Rock station was visited by the largest flock of birds I have seen this winter, viz.. Larks, Rose Linnets, Starlings, and other species which I did not see well enough to make out. Time when seen, 2 till 5 a.m.; wind light S.W. on arrival, and on departure fresh N.E. Fog and rain. Great numbers struck, but none found dead, though doubtless many fell into the sea. I have observed during the last two winters that the Golden-crested Wren and the Common Wren have not visited us as usual. I have seen these small birds thick on the windows, night after night, during the fall of the year." It is interesting to note here that between the 2nd and 11th March, 1880, a similar great migration took place past the Bell Rock, of which an account is given in my last report for 1879 [vide Zool., May, 1880].[3] At Bell Rock, 18th Feb., a great number of Larks, 8 p.m., light E.S.E., haze. Great numbers struck, none lying dead. Apparently this flock was entirely composed of Larks greatly exhausted. A number seen asleep all night on window-sashes; left at first streak of dawn. Feb. 19th, a small number of birds (species not determined) flew about in the rays of light all night; wind S.E., fresh, haze. 25th, great number of Larks during the night; wind light W.; striking, but none found dead; left, flying N.W. March 10th, one Black Crow seen asleep on balcony rail; left flying N.E., at 7 a.m.; wind fresh W.S.W., haze. 17th, one "Snowflake" flying from N.W. to S.E.; wind W.S.W., fresh, haze. In a letter accompanying this later schedule, Mr. Jack writes (28th March, 1881):—"I am sorry to say our close companions during winter, Dunters and Sea Pheasants, are still with us in great numbers. This we know by long observation to indicate that winter is not yet past for a season, nor can we judge so until they have all been gone for a week at least. In the fall of the year, when we see them return, we well know that winter is at hand. When stationed in the Isles of Shetland I have often remarked, when I heard much howling going on amongst the seals, that no good weather could be looked for, and I have never known this to fail."
[3] Later in March this year, viz. the 19th, an indication of a returning (?) migration of Shrikes is found in the occurrence of one bird at Bath Hill Wood, West Grange, Perthshire, not very far removed from the Alloa district. It was shot by Mr. J. Livingstone, and is now in the collection of Mr. J. J. Dalgleish.
General Remarks.
As already mentioned, we have received fewer returns this year from the East Coast than in 1879, having returns only from eight stations in 1880, against thirteen in 1879. This arises principally from actual scarcity of birds at many stations, and at some, from extra work devoted to duties of the reporters, owing to fogs and stormy weather. This scarcity appears to have extended all along our Scottish E. coast, and even showed itself for some distance down the East English coast. That, at no time, can our East of Scotland returns approach in magnitude those of the East English coast, I fully believe, because, in the weather most favourable for observation at the stations,—viz., foggy or thick nights,—lanterns placed a few feet above the water, as they are in lightships, must attract far more birds than higher lanterns at the lighthouses. The peculiar situations also of many of our Scottish stations—in the midst of towns (as at Cromarty and Kinnaird Head, in Frazerburgh), in inland bays and arms of the sea (as at Chanonry, and at many localities on our west coast)—must very materially alter the conditions of observation. At our more northern stations the lighthouses for the most part stand at great elevations, and it is worthy of note that from such stations as the Bell Rock, Pentland Skerries, and Whalsey Skerries, on the east coast, and Dhuheartach and Skerryvore, on the west coast, &c., we have the best filled schedules, showing that stations upon lower and isolated elevations are the best points of observation.
At the conclusion of my report for 1879, under the West Coast stations, I take notice of the N.W. to S.E. trend of the migration across Tyree and Loch Assapol in the Ross of Mull, and of the direction taken by birds across the narrow part of Scotland between the Firths of Forth and Clyde (vide 'The Zoologist,' May, 1880, pp. 202-204).
My present impression—from these and many similar observations in Stirlingshire and the districts named—is, that a semi-circular migration is probably carried on; birds which strike our coasts at more northerly points, or start from localities further north in Scotland itself, at certain points trend more southerly from their original E. to W. direction; and again, at certain other points, again trend more easterly from their previous N. to S. direction, and pass finally, as far as our British Islands are concerned, from N.W. to S.E. directions. This, of course, is more patent in some seasons than in others, depending upon prevailing winds and weather. Birds came to us all through the migratory season from E. to W. across the North Sea, except in 1879 at the Galloper Bank L.V. (Zool., May, 1880, p. 203). In 1879, I believe, as further indicated at the end of my report on the West Coast, that the migration was compressed by prevailing N.W. winds, and deflected further south, but in 1880 was more expanded, or less compressed, by prevalence of N.E. and E. winds, and that therefore the horizontal area of migration covered a larger surface. In 1880 we thus find birds migrating from directions south of East to directions north of West across the English Channel, or crossing from France to England (vide Cordeaux's Report antea). These points are put forward not as intended to be conclusive, but simply for the purpose of directing attention for further statistics. I will only further direct attention here to my "Third Ornithological Report for Scotland, 1880-81," read to the Natural History Society of Glasgow, session 1880-81.
In our last Report, 1879 (Zool., May, 1880), under our lists of lighthouses, we gave the descriptions of the lights, whether white or red, fixed, flash, revolving, or intermittent, or with other lights or action. What influence in attracting birds these various descriptions of light have, it would not yet be easy to ascertain, because—given the different colours and descriptions—we have them at different localities, which makes it almost impossible to compare them. However, broadly speaking, we would imagine the brightest, whitest, fixed lights to have most influence in penetrating fog or haze, and therefore of attracting birds. We considered it advisable to give these descriptions in our first Report, because we thought that in time such may prove of some value when our knowledge of migration increases. In the Report for 1880 we have not repeated these particulars, but, instead, we give, after the name of each lighthouse station, the heights of the lanterns above the sea, not because we can positively affirm that the height of any given light influences the total of birds seen or killed at that light, but because we believe that this particular may possibly elicit facts in future. Some of our reporters state extreme height above the sea as a cause of birds seldom or never striking the glass, or never being seen hovering round the light. Certainly, returns show a preponderance of deaths or other records, first, at lightships (the average height of the lights of which above the sea is only a few feet); secondly, at such stations—upon isolated rocks—as the Bell Rock, Dhuheartach, or Skerryvore (the lanterns of which are not more than sixty or seventy feet above the water); and a great preponderance above such stations as Cape Wrath (which is 400 feet above the sea) or other similarly elevated lights. During the daytime, whilst crossing towards the English coasts and past the lightships, flocks are usually seen flying low; and across the Firth of Forth and other narrow estuaries the same thing is observed. At times birds are seen passing high in air "almost beyond the range of vision," and when clouds or fogs rapidly lift or clear off during the time of migration, the said migration appears often to "cease to mortal vision," indicating, some say, a reascent to higher levels. Birds also are known to descend upon Heligoland almost perpendicularly from the sky, indicating, it is presumed, a course of migration at a great height, and a descent therefrom upon fog- or haze-covered land to rest or feed. To birds passing through the air above, a local fog beneath probably indicates land in the midst of water, and, if this be so, hence a descent upon it. The various numerical returns of those killed at lanterns are probably a good deal dependent on the height at which birds fly in foggy weather. We might call this the vertical area of birds' migration flight as opposed to lateral area.
Now it seems that light-vessels always return the best-filled schedules, and therefore a preponderance of birds are noticed all along the East English Coast, where light-vessels are most abundant. Whilst upon the East Scottish Coast the returns are infinitely smaller where there are no light-vessels, but only lighthouses, whose lanterns are at a greater height; and the question very naturally arises, "If the Scottish coasts were lighted with light-vessels, would not the number of records be very considerably augmented?"
Mr. J. Hardy's Notes from Berwickshire and the Borders.