Page images
PDF
EPUB

curves laterally. In a multitude of birds the bill curves downwards. In some, as in the avocet, it curves upwards; but in no other bird but this New Zealand plover does it curve on one side! Lastly a few words must be said concerning the curious and unpleasant Kea parrot. When Europeans first visited the island this parrot fed peacefully on nuts, cracking them with its powerful bill. After the introduction of sheep, however, it began to attack them, perching on their backs and tearing them with its very long and sharp-pointed bill to get at the kidney; so inflicting fatal injuries. This seems a quite unparalleled change of habit, but we suspect that, did we know all the antecedent conditions of New Zealand, the mystery might be explained.

A great number of birds have so wide a range as to be almost cosmopolitan. This is especially the case with gulls, petrels, and such creatures, but we have said nothing as yet about aquatic birds. The most remarkable of such are the penguins, though they are not cosmopolitan, but entirely confined to the Southern Ocean. The most striking kind is perhaps the king penguin, which exists in enormous numbers in the Falkland Islands, Kerguelen land, &c. It it quite unable to raise itself in the air, its wings being clothed, but with scale-like feathers, and it would thus seem to be as flightless as the ostrich or the apteryx. In truth, however, it may be said to fly submerged. It passes the greater part of its time in the water, and large portions of that time it spends beneath the surface, where it swims with its wings only, which are enormously powerful. Its feet serve but as rudders to direct its course. On land it assumes an extraordinarily upright attitude, and differs from every other bird by standing more or less completely on the soles of its feet-as we do-instead of only on the toes. inorants are birds very widely distributed, save in the Arctic regions. About forty species are to be found, and the common one and the Shag are usually to be seen on our coasts. In China the cormorant has been domesticated and trained to catch fish for its masters. Nearly allied to these birds are the darters a small group, of but four species, though distributed over America, South-Eastern Asia, Africa, and Australia. They are not sea-birds, but inhabit the swamps and rivers of warm latitudes, and the American species has long been exhibited at our Zoological Gardens, where its truly wonderful movements could be well and easily observed. The darter has a longish, straight, and very sharp beak and a long and slender neck, which bends in a peculiar way at a certain spot. At that spot the structure of the bones and ligaments of the neck abruptly

Cor

abruptly changes, the result being that the head can be thrown. suddenly forward with extreme rapidity, force, and accuracy. The darter propels itself under water so quickly as to be able, by this mechanism, to spear fish with its sharply-pointed beak. The bill is then as rapidly withdrawn, and the prey seized with the jaws and swallowed. A similar modification, to a much less marked degree, exists in the cormorant, and also in the booby, gannet, or Solan goose, and the pelican; which are thus shown to be all near allies.

Three birds, called skimmers, are respectively found in Asia, Africa, and America, and they differ from all other members of their class in having the upper division of their bill much shorter than the lower one. They have been observed flying backwards and forwards over the water, ploughing it with the lower and longer half of their most singular beaks. Yet what they live on is a question still disputed.

The petrels constitute a very numerous group of oceanic birds which very rarely come to land except to breed. They possess wonderful powers of flight, and are excellent swimmers, though they hardly ever dive. The various species differ very greatly in size, but they offer a marked contrast to gulls and terns in that they are silent birds. The renowned stormy petrel is not much larger than a swallow. They will nevertheless often accompany a ship for many days, and are the birds which sailors call 'Mother Carey's chickens.' The stormy petrels rove over the Atlantic, and have been occasionally taken in England. The largest of the group, and largest of all oceanic birds, is the wandering albatross. It possesses wings of enormous length, and is celebrated for its power of sailing in the breeze, without flapping them, for a very long period. It occasionally visits Europe, though its home is in the southern hemisphere.

Another wandering, oceanic species is the frigate bird, which also possesses enormously long wings. It is known also as the man-of-war bird, and ranges the ocean in all the warmer parts of the world.

This leads us to consider the wide distances which many birds occasionally traverse in those wonderful flights which are so generally undertaken by them at two seasons of the year. We refer to what is known as the migration of birds-a process which still remains enveloped in much mystery.

In very many birds this change of place is conspicuous and indisputable, but all birds practise it to some extent, so that 'migration' may be said to be really a universal habit in the class. The change of the seasons greatly affects the facility for finding

suitable

suitable food, and this alone suffices to induce some corresponding change of place, though it may but be a slight one, or may only cause some individuals out of many to make any considerable move. Birds, the individuals of which thus differ, are called 'partial migrants,' and amongst them even the robin may be included, familiar as he is in winter time to most country homes, and though most individuals stop with us all the year. But our migrants differ in this; some breed with us, and some do not. The birds, which come to us in winter, return to a northern home to rear their progeny, while the majority of our visitors, like our nightingales and our swallows, build their nests in England. There are, however, birds which are neither content with such warmth as our winter affords, nor can they endure our summer heat. Such birds pass over us twice every year, but never make a home in these islands. The southern journey which birds undertake is readily comprehensible, but the journey north is much more mysterious. It is a fact, that all birds breed in the coldest region they visit, whether it be towards the Arctic or Antarctic pole; why they do this, however, is by no means clear. Amongst the birds which pass over us is the little stint, which is only to be seen on our shores for a month in the spring, and another month in the autumn. These are two pauses which it makes in its northward and southward migration respectively. Mr. Seebohm supplies us with much interesting information about the migration of birds. Thus he tells

us

'The sanderling breeds on the shores of the Arctic Ocean; I have shot it in the lagoon of the Petchora in lat. 70° north, in the middle of the breeding season, and have watched it in the winter feeding on the coast of South Africa, about eight thousand miles further south. The knot has even a wider range, breeding further north and sometimes wintering further south; there can be little doubt that some of its "fly-lines" measure ten thousand miles. . . . Any ornithologist who visits the Sussex Downs on a fine day in autumn-no better place could be selected than that between Brighton and Shoreham-may see small parties of birds passing up and down the coast.... If he be a novice he will scarcely be likely to regard their apparent flitting to and fro as in any way connected with migration. But by-and-by he will probably discover that the birds, which are moving in the direction of Dover, are soft-billed insect-eating species, who are migrating cast to cross the Straits on their way to warmer winter-quarters down south; whilst those who are migrating towards the Land's End are hard-billed seed-eating species, who are

*The Geographical Distribution of the Charadriidæ,' p. 34.

migrating

migrating west. . . . The former birds are migrating out of England, the latter are migrating into it in autumn. . . . Each species has a fixed time of migration, which appears to be very slightly affected by the condition of the weather. Good weather does not seem to hasten the arrival of these birds at their breeding-grounds, nor does bad weather retard their movements. In their winter-quarters they are almost as punctual; and though many of these are reached by somewhat circuitous routes, it is remarkable how few birds lose their way on migration.'

He makes the following interesting remarks respecting migration in the southern hemisphere *:

'Little or nothing has been written of the migration of birds in the southern hemisphere, but it is almost as important a fact in the history of the birds of Natal as in that of British birds, though the difference in the geographical relations of the two countries modifies the details in many ways. It is a remarkable fact that whilst there are very many birds breeding in the northern hemisphere and wintering in the south, it is not known that any land bird breeds in the southern hemisphere and habitually winters in the northern. . . . One cause of this apparent anomaly may be the difference in the distribution of the land. North of the British Islands, and a similar latitude on the continent of Europe and Asia, is an Arctic region, which is the breeding-ground of great numbers of migratory birds. ... In the southern hemisphere there are no Antarctic breedinggrounds, whence similar migrants would visit Natal. No part of South Africa is cold enough to be a breeding-ground of Arctic birds, and the land at the Antarctic pole is too cold for them. The natural consequence of this state of things is, that in South Africa there are no migrants from the Antarctic region either in winter, or passing through in spring and autumn to winter further north.'

At the present moment, when so much political attention has been directed to Heligoland, it is not a little interesting to note how great is its ornithological importance. Mr. Seebohm says t:

There are many places where migration may be easily studied. The fly-lines of a great many species pass through Malta, and of perhaps still more through Gibraltar; but in no place has more migration been seen and recorded than on the island of Heligoland. This comparatively bare rock, which rises perpendicularly from the sca about 180 feet, scarcely measures 200 acres in extent, and contains perhaps 2000 inhabitants. In conjunction with Sandy Island, about a mile away, exposing say 50 acres of uninhabited sand-hills and beach at low water, reduced to scarcely half that extent at high tide, it has been visited by more species of birds than have been recorded from any country of Europe. The fact is, that

* Ibid. p. 37.

† Ibid. p. 40.

Heligoland

Heligoland is the only part of the world of which the ornithology has been properly worked. Every boy on the island is a born and bred ornithologist. The fisherman steers with a gun by his side, the peasant digs his potatoes with a gun on the turf and heap of birds on his coat. Every unfortunate bird that visits the island has to run the gauntlet of forty or more guns, to say nothing of scores of catapults and blowpipes. Every bird which appears is whistled within range with marvellous skill. Long before sunrise the island is bristling with guns, and after dark the netters are busy at their throstle-bushes; whilst at midnight the birds commit suicide against the lighthouse. The common birds are eaten, the rare ones are sold to the bird-stuffer, and the unknown ones are taken to the celebrated ornithologist Gätke.'

d

The following are notes from the Diary of the ornithologist referred to as to the occurrence of flocks of birds during observations carried on for thirteen years :

-

October, 1870.-Thousands of great tits.

February, 1876.-Tens of thousands of skylarks.
January, 1878.-Countless numbers of fieldfares.

December, 1879.-Millions of red-throated divers.
September, 1880.-Thousands of siskins.

November, 1880.-Thousands of shore-larks.

September, 1881.-Immense flights of common buzzard.
October, 1881.-Thousands of snow-buntings.

Countless numbers of hedge-sparrows.

October, 1882.-Thousands of jays.

Myriads of goldcrests.

September, 1883.-Enormous number of redstarts.

Mr. Seebohm records his own observations as follows*

'The casual visitor to Heligoland, who frequents the restaurant to enjoy the oysters and the lobsters, or rows across to Sandy Island to bathe on the shore and take a constitutional on the dunes, seldom sees much migration. Now and then a flock of waders may be detected hurrying past; flocks of pipits or wheatears occasionally land on the island, feed for an hour or two, and then pass on; and sometimes a scattered and straggling stream of hooded crows, of heavy and laborious flight, will continue all day long. Most birds migrate by night; very few come within sight of the island, and of those that do, not one in ten thousand stops to rest. Every flock which passes over probably drops a few tired or hungry birds; and after a migration-night a walk through the potato-fields in the early morning is most curious and interesting. The variety of species, and the incongruous way in which they are mixed, is quite startling. The potato-fields are practically the only cover on the island; and

[blocks in formation]
« PreviousContinue »