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The penguins of the Antarctic regions very rightly have been termed the true inhabitants of that country. The species is of great antiquity, fossil remains of their ancestors having been found, which showed that they flourished as far back as the eocene epoch. To a degree far in advance of any other bird, the penguin has adapted itself to the sea as a means of livelihood, so that it rivals the very fishes. This proficiency in the water has been gained at the expense of its power of flight, but this is a matter of small moment, as it happens.

In few other regions could such an animal as the penguin rear its young, for when on land its short legs offer small advantage as a means of getting about, and as it cannot fly, it would become an easy prey to any of the carnivora which abound in other parts of the globe. Here, however, there are none of the bears and foxes which inhabit the North Polar regions, and once ashore the penguin is safe.

The reason for this state of things is that there is no food of any description to be had inland. Ages back, a different state of things existed: tropical forests abounded, and at one time, the seals ran about on shore like dogs. As conditions changed, these latter had to take to the sea for food, with the result that their four legs, in course of time, gave place to wide paddles or “flippers,” as the penguins' wings have done, so that at length they became true inhabitants of the sea.

Were the Sea-Leopards(2) (the Adélies' worst enemy) to take to the land again, there would be a speedy end to all the southern penguin rookeries. As these, however, are inhabited only during four and a half months of the year, the advantage to the seals in growing legs again would not be great enough to influence evolution in that direction. At the same time, I wonder very much that the sea-leopards, who can squirm along at a fair pace on land, have not crawled up the few yards of ice-foot intervening between the water and some of the rookeries, as, even if they could not catch the old birds, they would reap a rich harvest among the chicks when these are hatched. Fortunately however they never do this.

Fig. 1. AN ANGRY ADÉLIE

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When seen for the first time, the Adélie penguin gives you the impression of a very smart little man in an evening dress suit, so absolutely immaculate is he, with his shimmering white front and black back and shoulders. He stands about two feet five inches in height, walking very upright on his little legs.

His carriage is confident as he approaches you over the snow, curiosity in his every movement. When within a yard or two of you, as you stand silently watching him, he halts, poking his head forward with little jerky movements, first to one side, then to the other, using his right and left eye alternately during his inspection. He seems to prefer using one eye at a time when viewing any near object, but when looking far ahead, or walking along, he looks straight ahead of him, using both eyes. He does this, too, when his anger is aroused, holding his head very high, and appearing to squint at you along his beak, as in Figure 1.

After a careful inspection, he may suddenly lose all interest in you, and ruffling up his feathers sink into a doze. Stand still for a minute till he has settled himself to sleep, then make sound enough to wake him without startling him, and he opens his eyes, stretching himself, yawns, then finally walks off, caring no more about you. (Figs. 2 and 3.)

The wings of Adélies, like those of the other penguins, have taken the form of paddles, and are covered with very fine scale-like feathers. Their legs being very short, they walk slowly, with a waddling gait, but can travel at a fair pace over snow or ice by falling forward on to their breasts, and propelling themselves with all four limbs.

To continue the sketch, I quote two other writers:

M. Racovitza, of the “Belgica” expedition, well describes them as follows:

“Imagine a little man, standing erect, provided with two broad paddles instead of arms, with head small in comparison with the plump stout body; imagine this creature with his back covered with a black coat … tapering behind to a pointed tail that drags on the ground, and adorned in front with a glossy white breast-plate. Have this creature walk on his two feet, and give him at the same time a droll little waddle, and a pert movement of the head; you have before you something irresistibly attractive and comical.”

Fig. 2. Dozing

Fig. 3. Waking up, Stretching, and Yawning

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Dr. Louis Gain, of the French Antarctic expedition, gives us the following description:

“The Adélie penguin is a brave animal, and rarely flees from danger. If it happens to be tormented, it faces its aggressor and ruffles the black feathers which cover its back. Then it takes a stand for combat, the body straight, the animal erect, the beak in the air, the wings extended, not losing sight of its enemy.

“It then makes a sort of purring, a muffled grumbling, to show that it is not satisfied, and has not lost a bit of its firm resolution to defend itself. In this guarded position it stays on the spot; sometimes it retreats, and lying flat on the ground, pushes itself along with all the force of its claws and wings. Should it be overtaken, instead of trying to increase its speed, it stops, backs up again to face anew the peril, and returns to its position of combat. Sometimes it takes the offensive, throws itself upon its aggressor, whom it punishes with blows of its beak and wings.”

The Adélie penguin is excessively curious, taking great pains to inspect any strange object he may see. When we were waiting for the ship to fetch us home, some of us lived in little tents which we pitched on the snow about fifty yards from the edge of the sea. Parties of penguins from Cape Royds rookery frequently landed here, and almost invariably the first thing they did on seeing our tents, was at once to walk up the slope and inspect these, walking all round them, and often staying to doze by them for hours. Some of them, indeed, seemed to enjoy our companionship. When you pass on the sea-ice anywhere near a party of penguins, these generally come up to look at you, and we had great trouble to keep them away from the sledge dogs when these were tethered in rows near the hut at Cape Evans. The dogs killed large numbers of them in consequence, in spite of all we could do to prevent this.

The Adélies, as will be seen in these pages, are extremely brave, and though panic occasionally overtakes them, I have seen a bird return time after time to attack a seaman who was brutally sending it flying by kicks from his sea-boot, before I arrived to interfere. An exact description of the plumage of the Adélie penguins will be found in the Appendix, as it is more especially of their habits that I intend to treat in this work.

Before describing these, and with a view to making them more intelligible to the general reader, I will proceed to a short explanation.

The Adélie penguins spend their summer and bring forth their young in the far South. Nesting on the shores of the Antarctic continent, and on the islands of the Antarctic seas, they are always close to the water, being dependent on the sea for their food, as are all Antarctic fauna; the frozen regions inland, for all practical purposes, being barren of both animal and vegetable life.

Their requirements are few: they seek no shelter from the terrible Antarctic gales, their rookeries in most cases being in open wind-swept spots. In fact, three of the four rookeries I visited were possibly in the three most windy regions of the Antarctic. The reason for this is that only wind-swept places are so kept bare of snow that solid ground and pebbles for making nests are to be found.

When the chicks are hatched and fully fledged, they are taught to swim, and when this is accomplished and they can catch food for themselves, both young and old leave the Southern limits of the sea, and make their way to the pack-ice out to the northward, thus escaping the rigors and darkness of the Antarctic winter, and keeping where they will find the open water which they need. For in the winter the seas where they nest are completely covered by a thick sheet of ice which does not break out until early in the following summer. Much of this ice is then borne northward by tide and wind, and accumulates to form the vast rafts of what is called “pack-ice,” many hundreds of miles in extent, which lie upon the surface of the Antarctic seas. (Fig. 4.)

It is to this mass of floating sea-ice that the Adélie penguins make their way in the autumn, but as their further movements here are at present something of a mystery, the question will be discussed at greater length presently.

When young and old leave the rookery at the end of the breeding season, the new ice has not yet been formed, and their long journey to the pack has to be made by water, but they are wonderful swimmers and seem to cover the hundreds of miles quite easily.

Arrived on the pack, the first year's birds remain there for two winters. It is not until after their first moult, the autumn following their departure from the rookery, that they grow the distinguishing mark of the adult, black feathers replacing the white plumage which has hitherto covered the throat.

The spring following this, and probably every spring for the rest of their lives, they return South to breed, performing their journey, very often, not only by water, but on foot across many miles of frozen sea.

Fig. 4. Pack Ice (on which the Adélies winter)

Two Weddell Seals are seen on a Floe

Fig. 5. Heavy Seas in the Autumn

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For those birds who nest in the southernmost rookeries, such as Cape Crozier, this journey must mean for them a journey of at least four hundred miles by water, and an unknown but considerable distance on foot over ice.

As I am about to describe the manners and customs of Adélie penguins at the Cape Adare rookery, I will give a short description of that spot.

Cape Adare is situated in lat. 71° 14′ S. long. 170° 10′ E., and is a neck of land jutting out from the sheer and ice-bound foot-hills of South Victoria Land northwards for a distance of some twenty miles.

For its whole length, the sides of this Cape rise sheer out of the sea, affording no foothold except at the extreme end, where a low beach has been formed, nestling against the steep side of the cliff which here rises almost perpendicularly to a height of over 1000 feet.

Hurricanes frequently sweep this beach, so that snow never settles there for long, and as it is composed of basaltic material freely strewn with rounded pebbles, it forms a convenient nesting site, and it was on this spot that I made the observations set forth in the following pages.

Viewed before the penguins' arrival in the spring, and after recent winds had swept the last snowfalls away, the rookery is seen to be composed of a series of undulations and mounds, or “knolls,” while several sheets of ice, varying in size up to some hundreds of yards in length and one hundred yards in width, cover lower lying ground where lakes of thaw water form in the summer. Though doubtless the ridges and knolls of the rookery owe their origin mainly to geological phenomena, their contour has been much added to as, year by year, the penguins have chosen the higher eminences for their nests; because their guano, which thickly covers the higher ground, has protected this from weathering and the denuding effect of the hurricanes which pass over it at certain seasons and tend to carry away the small fragments of ground that have been split up by the frost.

The shores of this beach are protected by a barrier of ice-floes which are stranded there by the sea in the autumn. These floes become welded together and form the “ice-foot” frequently referred to in these pages, and photographs showing how this is done are seen on Figs. 5, 6, 7 and 8.

At the back of the rookery, nesting sites are to be seen stretching up the steep cliff to a height of over 1000 feet, some of them being almost inaccessible, so difficult is the climb which the penguins have made to reach them.

Fig. 6. “… Throw up Masses of Ice,

Fig. 7. “… Which are Frozen into a Compact Mass as Winter approaches”

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On Duke of York Island, some twenty miles south of the Cape Adare rookery, another breeding-place has been made. This is a small colony only, as might be expected. Indeed it is difficult to see why the penguins chose this place at all whilst room still exists at the bigger rookery, because Duke of York Island, until late in the season, is cut off from open water by many miles of sea-ice, so that with the exception of an occasional tide crack, or seals' blow holes, the birds of that rookery have no means of getting food except by making a long journey on foot. When the arrivals were streaming up to Cape Adare many were seen to pass by, making in a straight line for Duke of York Island, and so adding another twenty miles on foot to the journey they had already accomplished.

When the time arrived for the birds to feed, some open leads had formed about half way across the bay, and those of the Duke of York colony were to be seen streaming over the ice for many miles on their way between the water and their nests. They seem to think nothing of long journeys, however, as in the early season, when unbroken sea-ice intervened between the two rookeries, parties of penguins from Cape Adare actually used to march out and meet their Duke of York friends half way over, presumably for the pleasure of a chat.

To realize what this meant, we must remember that an Adélie penguin's eyes being only about twelve inches above the ground when on the march, his horizon is only one mile distant. Thus from Cape Adare he could just see the top of the mountain on Duke of York Island peeping above the horizon on the clearest day. In anything like thick weather he could not see it at all, and probably he had never been there. So in the first place, what was it that impelled him to go on this long journey to meet his friends, and when so impelled, what instinct pointed out the way? This of course merely brings us to the old question of migratory instinct, but in the case of the penguin, its horizon is so very short that it is quite evident he possesses a special sense of direction, in addition to the special sense which urged him to go and meet the Duke of York Island contingent, and I may here remark that when we were returning to New Zealand in the summer of 1913, we passed troops of penguins swimming in the open sea far out of sight of land,—an unanswerable reply to those naturalists who still maintain that migrating birds must rely upon their eyes for guidance, and this remark applies equally to the penguins we found on the northern limits of the pack-ice, some five hundred miles from the rookeries to which they would repair the following year.

TABLE A
Mean date	Northern limit of pack	Miles from C. Adare	Southern limit of pack	Miles of pack N. and S.	Remarks
Feb. 3, 1839	68° S.	190	?	?	Balleny
Jan. 1, 1841	66° 30′	280	69°	150	Ross
Feb. 1, 1895	66° 15′	300	69° 45′	210	Kristensen
Feb. 8, 1899	66° 0′	315	69° 0′	180	Borchgravink
Feb. 27, 1904	?		70° 30′	?	Scott
Feb. 15, 1910	nil		nil		Terra Nova
Mar. 13, 1912	nil		nil		Terra Nova
Jan. 30, 1913	nil		nil		Terra Nova

Note.—Ross, Kristensen, Scott, Shackleton and Pennell all, however, found pack late in the season while trying to work west along the coast when only some forty-five to seventy-five miles north of Cape Adare, and all were turned by this pack.

According to Pennell, it appears probable that there is a great hang of pack in the sea west of Cape Adare and south of the Balleny Islands, and most likely it is here that the Adélies repair when they leave Cape Adare rookery in the autumn. I think, however, it is safe to assume that they seek the northernmost limits of the pack during the winter, as these would offer the most favourable conditions.

TABLE B
Date	Longitude	Northern limit	Extends N. and S. Miles	Minutes of latitude Northern limit is N. of Cape Adare
Jan. 12, 1840	166° E.	64° 30′	—	400 (Wilkes)
Jan. 3, 1902	178° E.	67° S.	140	250 (Discovery)
Dec. 31, 1902	180° E.	66° 30′	60	280 (Morning)
	Second belt	69°	30	130 (Morning)
Dec. 20, 1908	178° W.	66° 30′	60	270 (Nimrod)
Dec. 9, 1910	178° W.	64° 45′	300	390 (Terra Nova)
Dec. 27, 1911	177° W.	65° 20′	160	360 (Terra Nova)
Mar. 8, 1911	162° E.	64° 30′	270	400 (Terra Nova)

Fig. 8. “… And later, form the Beautiful Terraces of the Ice-foot”