When these white tufts were present the feathers comprising them were usually longer than the black feathers among which they appeared, so that they stuck out in an untidy manner, and were very conspicuous.

In marked distinction to the slight variations above described were the three "Isabelline" varieties that I preserved, and are now to be seen in the British Museum collection. As these variations are very startling, and of the greatest interest, I give below a full description of their plumage and soft parts.

_First specimen_ captured on the Cape Adare rookery on November 4, 1911.

_Iris_, light brown. _Eyelids_, white. _Bill_, light brown. _Feet_, white. _Claws_, light brown.

The whole of the area covered by black feathers in the normal bird was covered by those of a very light fawn, somewhat darker on the neck and shoulders than elsewhere. _s.e.x_, male.

_Second specimen_ captured on November 14, 1911.

_Iris_, light brown. _Eyelids_, white. _Bill_, light brown; mandible, blackish on dorsum; maxilla, blackish on cutting edges. _Feet_, white on both surfaces. _Claws_, light brown.

In place of the black feathers of the normal bird, there was a fawn-coloured plumage, darkest on head and neck; lightest at bottom of back, back of flippers, and on shoulders.

_s.e.x_, female.

_Third specimen_ captured on December 23, 1911.

_Iris_, light brown. _Feet_, browny white. _Claws_, brown. _Bill_, brown; very dark on dorsum of mandible. _Eyelids_, white with a pink tinge.

In place of the black feathers of the normal bird, this specimen had those of a very light cream colour: in fact very slightly darker than the white area but deepening in shade to light fawn on the head, neck, and shoulders.

_s.e.x_, male.

The second specimen had mated with a normal c.o.c.k. In each case the Isabelline birds were very much more docile than the normal forms. For instance, they did not struggle when picked up, as the others would have done, and the third specimen, when brought into our hut, gazed around with curiosity and apparent contentment, and showed not the least resentment at its captivity. A normal bird would have struggled and fought to the last extremity. Each bird was killed with chloroform.

So carefully did we keep the entire rookery under observation that I do not think it likely there were any more Isabelline forms. Thus we can conclude 3/750000 roughly represents the proportion of Isabelline forms among the species.

PART III

McCORMICK'S SKUA GULL

A book which treats of Adelie penguins scarcely can be complete without reference to the beautiful McCormick's skua gull (_Megalestris maccormicki_), as probably no Adelie rookery exists without its attendant band of skuas, who build their own nests very close to and occasionally among those of the penguins on whom they prey, almost entirely supporting themselves and their young upon the eggs and young offspring of their hosts.

Mention has been made of these birds from time to time through the previous pages, and some idea of their habits already will have been formed. In point of fearlessness they fall somewhat short of the Adelie, but exhibit, perhaps, rather more caution in their dealings with man than the gulls who visit St. James's Park in London and are fed by the children there, frequently from the hand, though probably in a very few days they might become extremely tame were their short experience of mankind made less bitter. The majority of explorers, like most men, though kindly by nature, are entirely thoughtless in their dealings with wild animals, and the skuas approach them only to be killed or severely injured by the ice-axes or rocks that are thrown at them in wanton sport as they light on the ground or hover near the visitors, whom they quickly discover to be their bitter and relentless foes.

Arriving at the rookeries somewhat later than the Adelies, they do not lay their eggs until the beginning of December. Practically no nest is made, a mere hollow being worked in the ground, in which the bird sits.

Frequently several hollows are made before the hen finally settles where she will lay. The two eggs, which are brownish olive thickly and darkly mottled with brown, are incubated for four weeks, after which the chicks are hatched.

From the moment of their first appearance from the egg these chicks exhibit the most extraordinary precocity. Covered with pale slaty-grey down, they look anything but the pugnacious little animals they turn out to be. Their one idea, besides feeding, seems to be to fight one another, and they may be seen to roll about the nest, locked together, fighting with beak and claw. They are fed from the ground, and may be seen picking about among the stones like the little domestic chickens, which they very much resemble. After a time invariably one of the chicks disappears, and as dead youngsters are not to be found, they are probably eaten by neighbours who have caught them wandering; in fact, Mr. Ferrar, of Captain Scott's first expedition, actually saw a Skua pick up a wandering chick of its own species and fly off with it, followed by a screaming flock of its neighbours, who sought to rob it of its prey.

In order to find out how many eggs a Skua would lay, I marked some nests, and took the eggs as they were laid. In each case a second egg was laid, but when this was taken no more appeared. In two nests I removed the first egg as soon as it was laid, but left the second, which was then sat upon by the parent, who was content with it, or unable to lay a third.

When any of us approached their nests the old birds would fly round in wide circles, making wild "stoops" at our heads each time they pa.s.sed over us, in the evident attempt to frighten us away. Occasionally they would actually knock our heads with a wing, and nothing seeming to scare them off, they would swoop past us time after time in a most disconcerting manner. In order to keep them at a distance without having to keep a constant look-out, when I was in the neighbourhood of their nest, I used to walk about holding a ski-stick or the handle of my ice-axe straight above me, and they would swoop at the top of this instead of my head, which was infinitely preferable. One day when a high wind was blowing on top of Cape Adare, I had my ice-axe knocked clean out of my hand by one of the Skuas flying straight into the handle, the heavy blow seeming to affect the bird but slightly.

There was a "skuary" on the screes, close to a thickly populated part of the rookery, but the majority of these birds made their nests right at the top of Cape Adare, from which point of vantage they surveyed the entire rookery, and a very sharp look-out they kept too, for no sooner did we start to flense a seal than a flock of them descended to gobble at the lumps of blubber as we threw them on the ground. In this occupation they exhibited the greatest jealousy, and when there was a hundred times as much blubber on the ground as all the skuas possibly could have eaten, they continually tried to drive each other away. When fighting they rarely stayed on the ground, but leapt at one another into the air, and one of the ill.u.s.trations shows two Skuas in the act of doing this. Their great spread of wing is well shown in this photograph.

(Fig. 71.)

When penguins' eggs were plentiful in the rookery the Skuas flew very low over the ground, and as they pa.s.sed over each colony of nests the sitting birds would crouch low upon them, a very necessary precaution, as I have described already in these pages the unerring way in which the Skuas picked up the penguins' eggs when they were left uncovered. Broken and empty sh.e.l.ls strewed the ground in the vicinity of the Skuas' nests, and it is probable that in a large rookery, such as that at Cape Adare, thousands of eggs are destroyed by them annually.

The instinct of the thief is most strongly marked in the Skua tribe, and I am afraid that the mere love of thieving alone actuates them on many occasions. For instance, when I was skinning a seal one day near Cape Evans I left a pair of field-gla.s.ses lying on a coat close by, and on looking round saw a Skua in the act of making off with them, holding them by the strap in his beak. A sudden yell caused the offender to drop the gla.s.ses, fortunately when they were but a yard from the ground.

Again, when the crew of an Antarctic ship were engaged in blasting the sea-ice which imprisoned it, a Skua flew off with one of the detonators which had been left on the ice. I think the detonator contained dynamite, but at any rate I am told that there was a stampede on the part of the men to get away from under the bird as it flew overhead!

When, with two companions, I visited a skuary at the back of the penguin rookery at Cape Royds, the Skuas circled over us in a way I have described above, but instead of swooping at our heads, some of them repeatedly dropped their guano on to us as they pa.s.sed over, timing the process with such surprising accuracy that I was. .h.i.t once, and Commander Campbell no less than three times. The following year when at Cape Adare, I expected the same treatment from the Skuas there, but curiously enough, these never did it. That one skuary should have adopted such tactics and another not, is a very curious thing, but it may possibly be that the Cape Royds Skuas discovered the trick during the stay of Sir Ernest Shackleton's expedition, who had spent a year there quite recently, and of the _Discovery_ expedition which spent two years at Hut Point, but a few miles distant, whereas the only men who ever inhabited Cape Adare wintered there some fifteen years before. But this is mere speculation.

[Ill.u.s.tration: Fig. 71. "Leapt at one another into the Air" (Page 129)]

[Ill.u.s.tration: Fig. 72. A Skua by its Chick (Page 131)]

When one of the parent Skuas is on the ground near its nest, on the approach of anyone it throws its head back, opens its wings, and loudly proclaims its whereabouts with its raucous cawing notes. When hovering over food, and at other times when not alarmed or angry, the sounds made by a Skua are very like those of the common Herring Gull, and not altogether unmusical at times, especially when making the little shrill piping note, by which I have often thought that gulls so nearly imitate the squeaking of a block in its sheaf.

When the penguin chicks are hatched, the Skuas prey upon these in a most cruel manner, and should a chick wander away from the protecting old birds, a Skua is almost certain to pounce upon and kill it. This it does by pecking its eyes out, after which, with powerful strokes of its beak, it gets to work on its back and quickly devours the kidneys.

The dead bodies of hundreds of chicks are seen strewn about the rookery, and especially in the neighbourhood of the Skuas' nests, as very often they carry them there. All these dead chicks are seen to have two holes picked through their backs, one on each side, corresponding to the position of each kidney.

Besides the penguins' eggs and young, there is another fruitful source of food for the Skuas to be found along the Antarctic coasts at the early part of the year, and that is during the time when the seals are bringing forth their young upon the sea-ice. The Skuas attend upon them then, and devour the after-births. In the second volume of the _Discovery_ reports Dr. Wilson mentions that large numbers of Skuas were noticed at Granite Harbour, and I have no doubt that they had congregated there for this purpose, as when pa.s.sing the spot on a spring journey along the sea-ice in 1912, we saw many hundreds of Weddell seals with their young. So many were there, that as we lay in our sleeping-bags during the night, the bleating of the little calves near our tents conveyed to our half-awakened senses the impression that we were in the midst of lambing fields at home!

The soft parts are coloured as follows:

_Bill_, black.

_Iris_, dark brown.

_Legs_, _toes_, and _webbs_, black, excepting a patch of bright blue just above the tibio-metatarsal joint, in young fledglings. Wholly black afterwards. (They have a very fine spread of webb.)

_Claws_, black.

The feathers of the head, neck, and breast vary from very light buff, or almost white, to rich dark brown.

Skuas' Time Table

+--------------------+-------------------+------------+ | | McMurdo Sound | Cape Adare | +--------------------+-------------------+------------+ | | 1902 1903 | 1911 | | 1st bird arrived | Nov. 3 Oct. 25 | Oct. 26 | | 1st egg seen | Dec. 9 Dec. 2 | Nov. 29 | | 1st chick hatched | Jan. 1 | | | Last bird left | Mar. 30 Apr. 7 | | +--------------------+-------------------+------------+

A SHORT NOTE ON EMPEROR PENGUINS(9)

(9) _Aptenodytes forsteri._

The Emperor is by far the largest of all penguins, weighing between 80 and 90 lbs. It is also a particularly handsome and graceful bird. By nature it seems much like the Adelie, except that its general demeanour is extremely dignified, and its gait, as it approaches you over the snow, slow and deliberate.

The most marked difference in the habits of the Adelie and the Emperor lies in the respective seasons at which each lays and incubates its eggs. Unlike the Adelie, which, as we have seen, chooses the warmest and lightest months of the year for the rearing of its young, the Emperor performs this duty in the darkest, coldest, and most tempestuous time.

The only reason that has been suggested for this custom is that many months must pa.s.s before the chicks are fully fledged. Were they hatched in December (midsummer) as are Adelies, autumn would find them still unfledged, and probably they would perish in consequence, whereas, being hatched in the early spring, they are fostered by their parents until the warmer weather begins, and then have the entire summer in which to accomplish their change of plumage.