130 



THE EDINBURGH JOURNAL OF NATURAL HISTORY, 



Having walked to Queensferry, we there went on board the steamer from New- 

 haven to Stirling, at eleven o'clock next day. The surface of the Frith vi-as exceed- 

 ingly smooth, and from Queensferry to Charleston was sprinkled with Guillemots, 

 Auks, Divers, and Gulls. The latter, however, were chiefly congregated, to an ex- 

 tent that one could hardly have conceived, along the northern shores, over the eddies 

 of which they hovered in pursuit of the young herrings that had been stationary there 

 for several weeks. The number seen at one glance along the coast could not be less 

 than a hundred thousand. The different species were easily distinguishable. Possi- 

 bW nine-tenths of the individuals belonged to the Black.headed kind, Larus ridibun- 

 dus, a most inappropriate name by the by, as its cries bear no resemblance to laugh- 

 ter. The young birds of this species were comparatively few, and did not generally 

 keep apart, though sometimes small groups of them might be seen ; of the remaining 

 tenth, one half belonged to the Common Gull, Larus canus, of which there seemed 

 lO be more young than old birds. The other half was composed of Herring Gulls, 

 Larus argentatuSy young and old. Smaller Black-backed Gulls, Larus fuscus, and 

 Greater Black-backed Gulls, Larus marimis, the latter in very small numbers. Two 

 Feasers were seen, both young birds, of a dusky colour, with the wings mottled uith 

 whitish, the tail even, and therefore probably Lestris pomarinus. They did not at- 

 tack the Gulls, but fished for themselves, picking up the small herrings from on wing. 

 The Guillemots, which were very numerous, but kept chiefly in the open part of 

 the Frith, sometimes rose as the vessel approached them, and ran, as it were, along 

 the surface in a straight line, flapping their wings all the while, to the distance of a 

 hundred yards or more, although most of them dived when we came near them. The 

 Red-throated Divers, which, although similar in colour to the Guillemots, were easi- 

 Iv distinguished by their superior size, and the comparatively greater length of their 

 necks, also frequently rose and splashed along to the distance of from two to four hun- 

 dred paces. Although they fly with great speed when fairly on wing, they are heavy 

 birds, and, in removing to a short distance, apparently do not think it necessaiy to 

 rise into the air as a Gull or Tern would do, but shoot out in a straight line, striking 

 the water with their wings and feet, the latter, in particular, throwing it to a distance 

 behind. 



Above Charleston, the Gulls and Divers disappeared from the open water, and 

 the flocks of the former seen along the bays were not more numerous than they would 

 be in ordinary cases. At Bo'ness, on the southern side of the Frith, not a single bird 

 of any description was to be seen. Near Alloa, however, we observed a flock of 

 smaller Black-backed Gulls, Larus fuscus, composed of thirty-eight individuals; and 

 farther up many birds of the same species, with a few of Larus canus^ Lartis argen- 

 tatus, and Lorvs ridibundvc, were seen floating here and there in the bays. In the 

 narrow part of the estuary, of which the flat margins are secured by low embank- 

 ments, and sometimes fringed with very tall reeds, Arundo Phragmites, a Heron, a 

 flock of Knots, Tringa dnerea, several Mallards, Anas Boschas^ and three Red 

 breasted Mergansers, Mergus serrator, were observed. 



On the whole, few sights could be more interesting to the ornithologist than that 

 of the vast number of sea-birds which are at present collected in the Frith, and es- 

 pecially in that part of it above Queensferry, to which doubtless they have been at- 

 tracted by the great shoal of small Herrings which have sought refuge there, and 

 which are caught in great quantities by the fishermen, and sold in the neighbouring 

 towns as an article of food — W.M.G. 



ON THE GEOGRAPHICAL DISTRIBUTION OF ANIMALS.^NO. II. 



The great source of the general equability and mildness of our climate is certainly 

 our connexion with the sea. The humidity of the air is referable also to the adjacency 

 of the ocean, the sea winds conveying with them the continued exhalations from its 

 surface ; but it depends likewise on the presence of our hills, which are great accu- 

 m.ulators of vapour, and attractors of the lower clouds. A great influence is also 

 exerted by our inland waters, which exhale considerable quantities of moisture. 

 Lastly, the great abundance of trees, and of vegetation generally, must have the 

 effect of condensing a large quantity of vapour, and of collecting a great quantity of 

 rain, and subsequently yielding it to the atmosphere. But the great alterations 

 effected in the appearance of our country by such extensive plantation and culture of 

 various kinds of vegetable produce, influence not only indirectly our Fauna through 

 the medium of climate, but also act directly on animals by accommodating a larger 

 number than could otherwise find subsistence with us. This adoption of new resi- 

 dences by animals is a fact so generally allowed that I need not here insist on it. 



I have stated that equability and mildness of climate influence our Fauna ; but does 

 humidity also ? 1 am not aware that it does. The two principal seasons in which 

 our Fauna is rendered extensive are, on the one hand, winter, when cold and storms 

 cause a great variety of waders and water-fowl to seek our shores, and, on the other, 

 ■■Mmmer, when the sun approaches us for a short space of time, and when humidity is 

 in a great measure obviated by the absence of sea winds. At all other seasons but 

 .mmmer, our climate is rendered colder than it would otherwise be, by the great 

 abundance of our wood, which forming considerable shelter, keeps o£F the benign in- 

 fluence of the sun's rays. Perhaps also, when our summers are not very hot, the 

 earth does not imbibe so much caloric as to allow of its giving off any subsequently, 

 to temper the severity of the winter's cold. This is in some measure borne o\it by 

 our experience of the last year. On the other hand, a compact soil, such as is ours, 

 generally has the quality of imbibing the fervour of the summer's sun, without re- 

 storing it to the air so readily as do loose sandy soils, so that a scorching atmosphere 

 is to a great extent prevented. On the whole, our summers may be stated as being 

 generally moderately hot, thereby preserving the character of uniformity to our cli- 

 mate, other circumstances above named having only minor degrees of power. Other 

 alterations in the surface of a country besides planting and culture affect the number, 

 condition, and situation of animals ; many are exterminated by man's interference, 

 some are thereby excited to unusual multiplication, many are restricted in their num- 

 bers, or in their range, or in both ; and some are encouraged to disperse locally or 

 generally. The alterations here referred to comprise tillage, draining, irrigation, 

 fencing, building, kc. As regards Devonshire, we find the number of quadrupeds 



diminished by the advances of agriculture and civilization. Many kinds of birds also 

 have been thereby lost to us, though possibly some species have been gained, and cer- 

 tainly the number of individuals has in many cases been increased, and a great variety 

 of alterations effected in geographic position. The number of our Insects and Mol- 

 luscous tribes has certainly been increased, and their geographic limits and positions 

 considerably interfered with, contracted, or enlarged. Many instances in point will 

 be afforded in the sequel. 



Very little needs be said on the subject of food as affecting the geography of ani- 

 mals. By the polity of nature, the vegetable world and the series of animals are in- 

 timately blended and connected: an extensive Flora will for the most part imply a 

 large proportion of animals, and so likewise the weaker creatures draw to them the 

 carnivorous tribes. In our county we find an extensive Flora, and our woods are 

 numerous and deep; the series of animals also is found very perfect, and the parts of 

 it would, if not subjected to our interferences and persecutions, be relatively propor- 

 tionate. Food influences the migration of animals to and from this country, subject, 

 however, to the higher influence of weather. In order to comprehend the relative 

 proportions of influence exerted by these two causes, we must suppose adverse and 

 propitious cases in point. If food is plentiful, and the weather intemperate, a sum- 

 mer bird of passage will forthwith undertake its journey, if near the usual period for 

 migrating; if food is scarce, and the weather fine, it will also depart; if both cir- 

 cumstances are adverse, it will hasten its departure still more decidedly ; and if pro- 

 vision be in plenty, and the weather fine, its stay will be prolonged. Similar remarks 

 might be made relative to winter migrants. Food has considerable influence in de- 

 termining the other kinds of migrations besides the vernal and autumnal. It also 

 causes a variety of unusual movements in animals, as will appear in detail. Food is 

 known to determine with precision the habitats of many kinds, though, as shown un- 

 der the head of Primary Laws, it has not that amount of power supposed by some, and 

 many situations producing the required pabulum, yet do not produce the animals so 

 dependent, and where, if removed, they thrive well. Our Bulimus fasciatus and 

 Helix virgata, which seemingly need maritime localities from some preference of food, 

 do not occur universally all along the coast, though the vegetation is seemingly uni- 

 form in character, but they are collected together in parties at certain spots. 



Man conducts a warfare against certain animals, which he finds or supposes to be 

 prejudicial to his interests. In some cases, as where by our agricultural operations, 

 &c. animals have been permitted to multiply more than their natural enemies would 

 have allowed, our destruction of their superfluous number is justifiable; and likewise, 

 in the case of such creatures, whose lives and actions are incompatible with our secu- 

 rity and actions, extirpation is demanded. Many of those animals, however, con- 

 signed to unlimited destruction, form important links in the chain of creation, and, 

 in consequence, their deficiency will cause alterations of various kinds in the pro- 

 ceedings of those other creatures with whom they were associated in the general 

 scheme and pohty of nature. The general destruction of our rapacious birds by 

 gamekeepers and others, must permit a vast accumulation of those species of smaller 

 animals on which they feed, and, in consequence, a more general and unnatural dis- 

 persion. A consideration, therefore, of the operations of man, whether as respects 

 his agricultural or his other improvements and refinements, or vrhether as regards 

 his hostilities to the animal creation, is worthy of some regard in framing an estimate 

 of the causes in active influence on the positions, ranges, and migrations of our native 

 animals of Devon. 



It is fairly to be presumed, that our acquaintance with secondary causes is as yet 

 very imperfect ; at least we are still unaware of the reasons of a very great number 

 of phenomena which, from being pecuhar to certain tribes, or to certain species, 

 cannot possibly be referable to general laws ; and until some light has been thrown 

 on these circumstances, our knowledge on this head must be deemed incomplete. 



Upon the whole, it will be found difficult to render an inquiry into circumstances 

 and detail interesting, though the chief objects and questions we shall have in view 

 v?ill be — firstly, to determine or illustrate general laws, if the limits of such an inves- 

 tigation should by possibility admit of it; secondly, to determine and illustrate se- 

 condary laws, or causes of geographic distribution, by attention to the following 

 circumstances : — Comparisons of the phenomena of this district with others of similar 

 extent, and similar or dissimilar aspect, and contingencies; irregular distributions; 

 the occurrence of varieties, and other modifications, as provisions to suit local circum- 

 stances ; the times selected for migration ("of the various kinds), with an attention to 

 the causes possibly influencing these movements ; modifications of habits ; peculiarities 

 in the Zoology of the whole of the spot selected, or in any of its parts ; remarkable 

 deficiencies in its Zoology; general, numerical, and other results. Lastly, it will be 

 right to make mention of a variety of other circumstances, though no explanation of 

 their occurrence can be given, since records of unexplained facts may serve to invite 

 notice and inquiry into causes. 



There are two methods of considering the Natural History of a given spot, each 

 having its peculiar advantages. We may investigate it with regard only to those 

 phenomena and circumstances properly and peculiarly its own, irrespectively of all 

 interferences and additions by the inroads of agriculture, planting, &c. ; or we may 

 consider it in its present state under all its alterations. The first mode has the ad- 

 vantage of being the more natural, and it is also calculated to display a great number 

 of remarkable features of the spot. The second plan has the advantage of setting 

 things in their present light, and serves also to show to what extent animals are 

 influenced by our proceedings, how far their distributions are modified by our ad- 

 vances and operations ; the instincts guiding them in their defences against our 

 intrusions ; and, lastly, it serves to demonstrate an important principle in the economy 

 of a great proportion of creatures, namely, that of adaptation to variety in surround- 

 ing conditions, a quality almost unrestricted in the human species, but enjoyed in a 

 more limited degree by animals, but without whicn their lives would he dependent 

 upon the slightest alterations in surrounding circumstances, and without which we 

 ahould not have been enabled to subject any of them to our uses and pleasures. I 

 believe it will be expedient to examine the Zoology of this district with reference both 

 to original and to existing features, giving to each its respective value, and peculiar 

 considerations. 



