FARTHEST SOUTH.

New Zealand Herald, Volume XLI, Issue 12545, 12 April 1904, Page 3

FARTHEST SOUTH.

THE BIRDS OF ANTARCTICA. INTERESTING DESCRIPTION BY DR. WILSON. PROTECTIVE COLOURATION. [copyright.] Describing tho birds of the Antarctic regions, Dr. Wilson writes: —We know a good deal of the penguins that we .met since we left England, thanks to the exertions of all who accompanied Mr. Ro'yds in his journeys to Cape Crofciev last year, Mr. Skelton especially, and Blisset, lance-cor-poral R.M.L.1., who was the lucky finder of the first Emperor penguin's egg, still the only authentic egg known, unless the Germans or the Swedes have been equally successful. There are other birds, however, that have every claim to be considered Antarctic, birds . that are quite unknown away from the ice of these southern regions, and, further, there are birds which are met with by everyone that comes within the Antarctic Circle, but which are not. limited to ice-bound regions. For example, we have the snow petrel, the Antarctic petrel and skua, which were seen so abundantly in the summer months; MeCormack's skua, as he is known to science, and an excellent change from seal meat, as he lias corno to be known to ourselves this winter. These three birds never leave the neighbourhood of ice. But the Giant petrel, Wilson's petrel, and the silver-gray Southern Fulmar petrel, are birds which have a far wider range than the Antarctic area. The Southern Fulmar, for instance, has been, killed off the coasts of South Africa and South America. The Giaut petrel we ourselves met with as os early as September, ISOI, when we were in latitude 35 S., and all through October and November we rarely missed his ungainly figure somewhere near the ship. And as for the little martin-like Wilson's petrel, it would bo hard to find a more world-wide traveler, for he is known in almost every ocean of the globe, and has been seen on the coasts of Britain again and again. Still, these three are typically Antarctic birds, and could not be omitted. Wilson's petrel breeds here, as well as on the islands about, the latitude of Kerguelen, where the other two do all their breeding. It is strange, and not a little disappointing. that we saw so few of these southern birds since we settled into winter quarters. The reason must be that we are too much cut off from open water, and, consequently only such a bird as the skua, which we provide with seal for food, dares to visit us iu any number. For the rest we have nothing, and we are far from their food supply, which is so abundant among the disintegrating ice of the ick. There they congregate, and, as near there as possible they breed at Cape Ad a re. for ample, and the Possession Islands, and, no doubt, at the new island discovered by the Morning on her way to us. THE SNOW PETREL. No one has yet discovered the nestingplace of the Antarctic petrel, and, now that we have discovered the Emperor's egg, this is the only bird that lives down here whose egg is still unknown. Snow petrels* eggs were taken in some numbers by MeCormack, in Ross' expedition, on Cockburn and Franklin Islands, and bv members of the Southern expedition at Cape Ada-re and in Robinson Bay. Here they lay their single white eggs in holes and crannies of the cliff, to the height sometimes wf 1400 ft. At Cape A dare the end of November is given as the date to look for them, but even during the first week in January there were still eggs to bo found on Cockburn Island, though they were well incubated. The appearance of "these snowwhite birds to those who were sledging to the south last year, .way on the barren surface of the Barrier, 60 miles from their food supply, was as surprising as it was refreshing, and created no little excitement among the dogs, who last saw winged game some seven months before.

Our first, introduction to snow petrels on the Discovery was coincident with her introduction to the ice in November. 1901. It has been the same with every ship in these latitudes. They did not follow us out of the ice. We met them again with the pack on January 3, 1902, and from thatday to me end of the first week in February they were our most constant attendants. On January 11 we were off the Possession Islands, and saw immense flocks of them alternating with flocks of Antarctic, petrels. The difference in the it habit of thght- was well contrasted, for whereas the Antarctic petrels wheeled and soareu as though by concerted action, as starlings flying in Hock, ttie snow petrels were flying in all directions at once, as one sees at Home a collection of swallows migrating in October. They were feeding, too, about- this time so close to the ship that one could see their method of feeding as plainly as the shrimplike schizopod on which they fed. This little beast was thrown up on the weather side of the ice Hoes by the breaking surf, and before the next wash could restore it to the water, down would drop a snow petrel to hover for a moment in the spray and pick it- off. Undoubtedly this is the reason why they are plentiful among broken ice and less plentiful where the sea is clear or the ice is high and unbroken, as it- is along tie Barrier. At our winter quarters but few were seen throughout- last summer, and they were only casual visitors; the unbroken flow proved no attraction to them. THE ANTARCTIC PETREL. Still less have we seen of the Antarctic petrel. None visited our winter quarters last summer, and though we- saw large flocks near Posse-sion Islands on January 11, 1902, and numbers scattered about the ice-bound const of the land of our furthest East, we have seen none since. Where they rest, and what their migrations are, no one knows. We have seen of them what others have seen, and nothing more. WILSON'S PETREL. The same must be said of the little Wilson's petrol, which we. were fortunate enough to catch uestiag at Cape Adare. Here, in a burrow some 3ft long, under a heavy mass of rock, we were led to a nestby the constant hovering of the bird around the entrance. The floor of the tunnel to the end where the nest lay was the hard ice. which required long chipping to admit an arm, but when the end was reached there was found a strange collection. Jn a warm nest of penguin's feathers lay the flattened mummy of a. petrel, a very rotten egg, and another egg clean and recently laid. Sitting together on these were two twittering Wilson's petrels, both iu the best of plumage. This is how they are generally found, several birds and often several eggs in one nest, though there is no doubt whatever that one bird lay." but one egg in the season, and that nearly half of its own size. This little petrel is not unlike several others which we saw -in milder climates, but from all of them it car./ be distinguished by the length and slenderness of its leg:: and the bright orange webs of its feet. Since settling into winter quarters we have seen nothing of the bird, save that oil two occasionr- when a sledge party was passing the end of White Island, miles away from open water, oue of these little petrels came and hovered round the sledges.

THE SOUTHERN FULMAR. Of the Southern fulmar there is even less to be said. Since we left 1 the pack ice proper we have not seen one, and unless on the way north we run into pack ice, there is but little, probability that we shall see the bird again. It is nowhere common, though so widely distributed. It is said to breed at Kerguelen Island, but there is still some- uncertainty, about its nesting habits. / THE GIANT PETREL. Of the Giant petrel, the "Nellie' or "Stinkpot," call him which vou will, we saw tar more hi mildei climate: than we have seen since wo entered the ice. At Cape Adare it i: tru: that wt saw a number, and among then? all varieties of shade, from the white -'lbino tr the chequered gray and tin J ark individuals, of which some were dark all over, even to blackness, and

others had light coloured heads and neck contrasting with. their darker bodies. It is strange that we should have found here a dozen oi so of this albino variety, for a white Giant petrel was considered a great rarity by the members ot ' the Southern Cross expedition, nor was more than one seen there during the whole time of their "Stay at Capo Adare. The "Nellie" has never been found nesting so far south of the Circle, but breeds freely at most of tho islands that lie o short way north ofit. Variability is its marked characteristic, far more so than it is of the skua, whose changes, we see, bear some relation to the age of the • individual. It appears, however, that the variations in the Giant petrel are independent of sex and age, and it may result in some way from the safety it enjoys from enemies that it has no need in the economy of life to maintain any definite colouring, and therefore individual variation has full play. MYSTERY OF COLOURATION. It. is always a little puzzling to account '.for what is apparently protective colouration in the skuas in these regions, for they would seem to have no need of it, since there is no bird or beast to molest them. Both the skuas themselves and the eggs, when sitting, aro very hard to see, and the chicks are equally invisible, and appear to know it, for they remain absolutely motionless when one is anywhere near them. There seems no need for this at all in these regions, though there may be good reason for it in their very close relations to the Antarctic skuas that we found breeding on Macquarie Island. In the case of the Giant petrel it may be that the species is divided into two, a darker and a lighter. It. seems very certain that the lighter variety is much more often seen the farther south one goes, for in all references to the bird in the milder regions an albino is always mentioned as a rarity, fat more so than we should consider it from what- we have seen down here. Therefore, it may he that the future may produce a white giant typical of tho Antarctic regions, as it has produced the white Snow petrel and the while seal. But why should any of these be white? Not for protection's sake, for the " Nellie" wants no protection. Not for the sake of obtaining tood, for the " Nellie" is a carrion feeder, as we saw at Cape Adare, requiring no stealth to possess itself of more dead penguins than it can possibly manage to eat. In the north, where birds and beasts must protect themselves from owls, stoats, foxes, and bears, it is easy to see that white will make them less conspicuous. And the ptarmigan, lemmings, and hares, upon which the animals mentioned subsist, are more easily stalked if the stalker is as white as snow. This, also, is easily understood. But in the south, not only* are the white birds not preyed upon, but neither do they require invisibility to pick crustaceans off an ice-floe, or to devour % penguin that has already died anatural death.

It looks rather as though the climate itself had more to do with the tendency to whiteness in the south, indicating, perhaps, some need for regulating the absorption of the sun's heat. Which wa> this works it would be unwise to guess without experiment, for it is a recognised fact that some white materials, white lead, for example, absorb us much heat as lamp-black and a good deal more than Indian ink. Some feathers may do the same. THE SKUA. Evidently the first year's skuas are dark brown all over, with a very faint tinge of straw colour at the back of the neck, and this dark colour remains, I believe, for some years, the golden tinge on the neck increasing gradually throughout life, even after the head, neck, and underparts have all turned a hoary gray, for the golden sheen is even more marked then. The feathers are much weathered towards the summer, and the whiteness of the quills gives a still more worn and bleached appearance to the feathers of the back. Of their nesting I need say little, for the eggs and young have been seen by all. One thing may have escaped notice, namely, that at Cape Adare, where we saw so many young birds of all ages, as well as eggs, and at Granite Harbour the same thing was borne out, although two eggs were always found and, when recently hatched out, two chicks were always in the nest, in the more advanced stages of growth there was never more than one survivor: the second had always disappeared. Those who went adrift on an ice-flow in Lady Newnes' Bay had the opportunity of seeing the skuas force their brethren to disgorge on the wing in precisely the same way as that in which the northern birds treat gulls. For in every way they are very like the northern skuas and other gulls. * They tend to breed in colonies, not always close to a penguin rookery.- That their sense, of sight and smell is acute was pretty certainly proved on the southern sledge journey—for on several occasions when a dog was killed and cut up in a southerly breeze the camp was visited by a skua or two soon after. They were seen on the Barrier as far south as 80 degrees 20 minutes latitude, some 150 miles from open water.

From last year's experience we may expect to see them in winter quarters again at the beginning of November. Belated individuals were seen on March 30. in 1902, and on April 7, 1903, but had we not provided them with food by killing seals there is little doubt that they would have left us last summer earlier linn they did the previous one. We have seen them eat Atlelie penguins' eggs and young,- but this lasts them only a month or two, and no toubt they make the most of it, as we do when we can. But for the fish and crustaceans that form their ordinary diet (hey must have open water.

SURMISES. This brings to an. end the short list of bilds that have so far acclimatised themselves to the Polar regions in the south as to be able to find a living. One would think it must be uphill work and that much stress of some kind must have been put upon a bird in temperate climates to induce it- gradually to leave them for good as the Snow petrel has, for instance, and the Emperoi and Adelie penguins. It would appear that ot all three birds the Snow petrel was one of the earliest to take to Polar life. llie difference in colour or the chicks of the King and Emperor penguins seems to indicate that they parted company earlier in then history than one would be led to think, judging only from the present; similarity of the adults. It is possible. however, that there was * greater number of bird forms adapted to ibis climate at the time when the southern glaciation extended somewhat farther to the north, and that of these only one or two have found reasons for carrying their acclimatisation to a more perfect state. Ot these reasons there is no doubt the two most powerful ones are the struggle to obtain food for themselves and their young, and the struggle to avoid exposing themselves and theii young as food for their enemies. But the question here touched upon is a very difficult one. All we can hope to do at present is to find out every detail of the life of every bird we see, here, noting, above all, in what ways they seem to be well or ill-adapted to the life, what are (hen enemies, what their dangers, what their food, and in what various ways they manage to avoid the one while obtaining the other. When more is known it will be more possible to - try and realise, a little deepei than we can at present, something ot the history of theii past.