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After each bout of a few minutes both birds became so exhausted that they sank panting to the ground, evidently suffering from thirst and at the limit of their endurance. Sometimes one captured the nest, sometimes the other, but after several hours of this, one of them began to show signs of outlasting the other, and kept possession. For long after this, however, the other returned repeatedly to the attack.
[Ill.u.s.tration: Fig. 43. JUMPING FROM THE WATER ON TO SLIPPERY ICE (Page 82)]
I fetched my camera and photographed the birds as they fought (Fig. 36).
As time went on, the weaker bird took longer and longer intervals to recover between his attacks, lying on his breast, with his head on the snow and eyes half closed, so that I thought he was going to die. Each time he got to his feet and staggered at his enemy, the latter rose from the nest and met him, only to drive him back again. When I saw them at about 10 P.M. (it was perpetual daylight now) both were lying down, the victor on the nest, the vanquished about five yards off. The next day one bird remained on the nest and the other had gone, and I do not know what happened to him.
In the course of a walk through the rookery considerable diversity in the choice of nesting sites was to be noticed. The general tendency is for the penguins to build their nests close together (within a foot or two of one another) on the tops of the rounded knolls, the lower levels being left untenanted.
The most thickly populated districts were to be found on the screes immediately below the cliffs. These screes having been formed in the first instance by the falling of fragments due to weathering of the cliff, their substance is still added to, little by little, as time goes on, and therefore many are killed annually by falling rocks, as is mentioned elsewhere, but weighing against this danger is the advantage the cliff offers as a shelter from the E.S.E. gales. The same applies to the nesting sites up the cliff, but I am convinced that only the love of climbing can account for the extraordinary positions chosen by some of the birds. Some of the nests are so difficult of access that their occupants, on their way to them, may be seen sliding backwards down the little glazed snow-slopes several times before they accomplish the ascent, whilst in other places they have to jump from one foothold to another along the almost perpendicular cliff.
Even up these heights a tendency to grouping is seen, though there are a fair number of individuals who, seeming to seek seclusion, make their nests at some distance from the others. I noticed this in some places along the sh.o.r.e, too, where solitary nests were to be seen on isolated patches of s.h.i.+ngle.
When I visited Cape Royds in 1911 I found a couple nesting alone in a cove known as "Black Sand Beach," some half mile from the rookery there.
Such isolation as this, however, is very unusual, and was quite a departure from the regular custom of the species.
[Ill.u.s.tration: Fig. 44. "WHEN THEY SUCCEEDED IN PUs.h.i.+NG ONE OF THEIR NUMBER OVER, ALL WOULD CRANE THEIR NECKS OVER THE EDGE" (Page 83)]
In some places at Cape Adare, large rocks some two or three feet in height stood about the rookery. Whenever the summit of one of these was accessible, a pair built their nest upon it,(4) though how they managed to keep up there during the gales was a matter for wonder, but the proud possessors of the castle evidently had a delight in their lofty position. One nest had been made on an old packing-case left by the expedition which wintered there in 1894, and several nested among the weathering bones of the seals that had died on the beach.
(4) Fig. 37.
Although the greatest care had been taken by nearly all in the choice of sites that would be on dry ground when the thaw came later in the season, yet a few hens had gone to the other extreme, and with greatest stupidity chosen their site right down in the hollows where they were absolutely certain to be flooded later on. These stupid ones are thus prevented from rearing their young, and so selection keeps the wiser for future generations, and eliminates the less intelligent from the community, though perhaps some of these learn by experience, and next year use more discrimination in choosing their nesting place.
Some of the colonies--in fact, most of them--were orderly and well arranged, and later in the season distinctly peaceful. Others, however, presented a less respectable appearance. There was one in particular, close to our hut, which could only be described as a slum of the meanest description. All through the season there was more fighting in this colony than anywhere else, and so remarkable was this, that we christened the locality "Casey's Court" and the name stuck for the rest of the year.
The nests had fewer stones than elsewhere, and were more untidily made, and when the eggs came, owing to the constant fighting that went on, most of them got spilt from the nests or broken, and very few chicks were hatched in consequence, the mortality among them also being so great that of the whole colony of some hundred nests, I do not think more than forty or fifty chicks at most reached maturity. The explanation of this state of things lay, I believe, in the fact that our hut and its curtilage deflected the stream of penguins on their way past the spot from the water to the back of the rookery, so that a constant stream of them pa.s.sed through "Casey's Court," upsetting the tempers of the inhabitants so that they became disorderly. In addition to this, there was a fairly big thaw pool and much miry ground near by, so that the inhabitants were generally covered with mud and very disreputable to look at.
[Ill.u.s.tration: Fig. 45. DIVING FLAT INTO SHALLOW WATER (Page 83)]
During the fasting season, as none of the penguins had entered the water, they all became very dirty and disreputable in appearance, as well may be imagined considering the life they led, but now that they went regularly to swim, they immediately got back their sleek and spotless state.
From the ice-foot to the open water, the half mile or so of sea-ice presented a lively scene as the thousands of birds pa.s.sed to and fro over it, outward bound parties of dirty birds from the rookery pa.s.sing the spruce bathers, homeward bound after their banquet and frolic in the sea. So interesting and instructive was it to watch the bathing parties, that we spent whole days in this way.
As I have said before, the couples took turn and turn about on the nest, one remaining to guard and incubate while the other went off to the water.
On leaving their nests, the birds made their way down the ice-foot on to the sea-ice. Here they would generally wait about and join up with others until enough had gathered together to make up a decent little party, which would then set off gaily for the water. They were now in the greatest possible spirits, chattering loudly and frolicking with one another, and playfully chasing each other about, occasionally indulging in a little friendly sparring with their flippers.
Arrived at length at the water's edge, almost always the same procedure was gone through. The object of every bird in the party seemed to be to get one of the others to enter the water first. They would crowd up to the very edge of the ice, dodging about and trying to push one another in. Sometimes those behind nearly would succeed in pus.h.i.+ng the front rank in, who then would just recover themselves in time, and rus.h.i.+ng round to the rear, endeavour to turn the tables on the others.
Occasionally one actually would get pushed in, only to turn quickly under water and bound out again on to the ice like a cork shot out of a bottle. Then for some time they would chase one another about, seemingly bent on having a good game, each bird intent on finding any excuse from being the first in. Sometimes this would last a few minutes, sometimes for the better part of an hour, until suddenly the whole band would change its tactics, and one of the number start to run at full tilt along the edge of the ice, the rest following closely on his heels, until at last he would take a clean header into the water. One after another the rest of the party followed him (Fig. 38), all taking off exactly from the spot where he had entered, and following one another so quickly as to have the appearance of a lot of shot poured out of a bottle into the water. The accompanying photograph presents this last scene.
[Ill.u.s.tration: Fig. 46. DIVING FLAT INTO SHALLOW WATER (Page 83)]
A dead silence would ensue till a few seconds later, when they would all come to the surface some twenty or thirty yards out, and start rolling about and splas.h.i.+ng in the water, cleaning themselves and making sounds exactly like a lot of boys calling out and chaffing one another.
So extraordinary was this whole scene, that on first witnessing it we were overcome with astonishment, and it seemed to us almost impossible that the little creatures, whose antics we were watching, were actually birds and not human beings. Seemingly reluctant as they had been to enter the water, when once there they evinced every sign of enjoyment, and would stay in for hours at a time.
As may be imagined, the penguins spent a great deal of time on their way to and from the water, especially during the earlier period before the sea-ice had broken away from the ice-foot, as they had so far to walk before arriving at the open leads.
As a band of spotless bathers returning to the rookery, their white b.r.e.a.s.t.s and black backs glistening with a fine metallic l.u.s.tre in the sunlight, met a dirty and bedraggled party on its way out from the nesting ground, frequently both would stop, and the clean and dirty mingle together and chatter with one another for some minutes. If they were not speaking words in some language of their own, their whole appearance belied them, and as they stood, some in pairs, some in groups of three or more, chattering amicably together, it became evident that they were sociable animals, glad to meet one another, and, like many men, pleased with the excuse to forget for a while their duties at home, where their mates were waiting to be relieved for their own spell off the nests.
After a variable period of this intercourse, the two parties would separate and continue on their respective ways, a clean stream issuing from the crowd in the direction of the rookery, a dirty one heading off towards the open water, but here it was seen that a few who had bathed and fed, and were already perhaps half-way home, had been persuaded to turn and accompany the others, and so back they would go again over the way they had come, to spend a few more hours in skylarking and splas.h.i.+ng about in the sea.
[Ill.u.s.tration: Fig. 47. DIVING FLAT INTO SHALLOW WATER (Page 83)]
In speaking of these games of the penguins, I wish to lay emphasis on the fact that these hours of relaxation play a large part in their lives during the advanced part of the breeding period. They would spend hours in playing at a sort of "touch last" on the sea-ice near the water's edge. They never played on the ground of the rookery itself, but only on the sea-ice and the ice-foot and in the water, and I may here mention another favourite pastime of theirs. I have said that the tide flowed past the rookery at the rate of some five or six knots. Small ice-floes are continually drifting past in the water, and as one of these arrived at the top of the ice-foot, it would be boarded by a crowd of penguins, sometimes until it could hold no more. (Fig. 39.) This "excursion boat,"
as we used to call it, would float its many occupants down the whole length of the ice-foot, and if it pa.s.sed close to the edge, those that rode on the floes would shout at the knots of penguins gathered along the ice-foot (Fig. 40) who would shout at them in reply, so that a gay bantering seemed to accompany their pa.s.sage past the rookery.
Arrived at the farther end, some half a mile lower down, those on the "excursion boat" had perforce to leave it, all plunging into the tide and swimming against this until they came to the top again, then boarded a fresh floe for another ride down. All day these floes, often crowded to their utmost capacity, would float past the rookery. Often a knot of hesitating penguins on the ice-foot, on being hailed by a babel of voices from a floe, would suddenly make the plunge, and all swim off to join their friends for the rest of the journey, and I have seen a floe so crowded that as a fresh party boarded it on one side, many were pushed off the other side into the water by the crush.
Once, as we stood watching the penguins bathing, one of them popped out of the water on to the ice with a large pebble in its mouth, which it had evidently fetched from the bottom. This surprised me, as the depth of the sea here was some ten fathoms at least. The bird simply dropped the stone on the ice and then dived in again, so that evidently he had gone to all the trouble of diving for the stone simply for the pleasure of doing it. Mr. J. H. Gurney, in his book on the gannet, says they (gannets) are said to have got themselves entangled in fis.h.i.+ng-nets at a depth of 180 ft. and that their descent to a depth of 90 ft. is quite authentic, so that perhaps the depth of this penguin's dive was not an unusual one.
[Ill.u.s.tration: Fig. 48. Diving Flat]
[Ill.u.s.tration: Fig. 49. Adelies "Porpoising" (Page 80)]
The tide at the open water leads where they bathed ran a good six knots, but the Adelies swam quite easily against this without leaving the surface.
In the water, as on the land, they have two means of progression. The first is by swimming as a duck swims, excepting that they lie much lower in the water than a duck does, the top of the back being submerged, so that the neck sticks up out of the water. As their feet are very slightly webbed, they have not the advantages that a duck or gull has when swimming in this way, but supplement their foot-work by short quick strokes of their flippers. This they are easily able to do, owing to the depth to which the breast sinks in the water.
The second method is by "porpoising."
This consists in swimming under water, using the wings or "flippers" for propulsion, the action of these limbs being practically the same as they would be in flying. As their wings are beautifully shaped for swimming, and their pectoral muscles extraordinarily powerful, they attain great speed, besides which they are as nimble as fish, being able completely to double in their tracks in the flash of a moment. In porpoising, after travelling thirty feet or so under water, they rise from it, shooting clean out with an impetus that carries them a couple of yards in the air, then with an arch of the back they are head first into the water again, swimming a few more strokes, then out again, and so on.
I show a photograph of them doing this (Fig. 49).
Perhaps the most surprising feat of which the Adelie is capable is seen when it leaps from the water on to the ice. We saw this best later in the year when the sea-ice had broken away from the ice-foot, so that open water washed against the ice cliff bounding the land. This little cliff rose sheer from the water at first, but later, by the action of the waves, was under-cut for some six feet or more in places, so that the ledge of ice at the top hung forwards over the water. The height of most of this upper ledge varied from three to six feet.
[Ill.u.s.tration: Fig. 50. A PERFECT DIVE INTO DEEP WATER (Page 83)]
Whilst in the water the penguins usually hunted and played in parties, just as they had entered it, though a fair number of solitary individuals were also to be seen. When a party had satisfied their appet.i.tes and their desire for play, they would swim to a distance of some thirty to forty yards from the ice-foot, when they might be seen all to stretch their necks up and take a good look at the proposed landing-place. Having done this, every bird would suddenly disappear beneath the surface, not a ripple showing which direction they had taken, till suddenly, sometimes in a bunch, sometimes in a stream, one after the other they would all shoot out of the water, clean up on to the top of the ice-foot. (Figs. 41 and 42.) Several times I measured the distance from the surface of the water to the ledge on which they landed, and the highest leap I recorded was exactly five feet. The "take off" was about four feet out from the edge, the whole of the necessary impetus being gained as the bird approached beneath the water.
The most important thing to note about this jumping from the water was the accuracy with which they invariably rose at precisely the right moment, the exact distance being judged during their momentary survey of a spot from a distance, before they dived beneath the water, and carried in their minds as they approached the ice. I am sure that this impression was all they had to guide them, as with a ripple on the water, and at the pace they were going, they could not possibly have seen their landing-place at all clearly as they approached it, besides which, in many cases, the ledge of ice on which they landed projected many feet forwards from the surface, yet I never saw them misjudge their distance so as to come up under the overhanging ledge.
During their approach they swam at an even distance of about three or four feet beneath the surface, projecting themselves upwards by a sudden upward bend of the body, at the same time using their tail as a helm, in the manner well shown in one of my photographs, in which one of the birds is seen in the air at the moment it left the water, the tail being bent sharply up towards the back.
Their quickness of perception is shown very well as they land on the ice. If the surface is composed of snow, and so affords them a good foothold, they throw their legs well forward and land on their feet, as shown in Figs. 41 and 42, but should they find themselves landing on a slippery ice-surface, they throw themselves forward, landing on their b.r.e.a.s.t.s in the tobogganing position as shown in Fig. 43.
The Adelies dive very beautifully. We did not see this at first, before the sea-ice had gone out, because to enter the water they had only to drop a few inches, but later, when entering from the ice terraces, we constantly saw them making the most graceful dives.
[Ill.u.s.tration: Fig. 51. SEA-LEOPARDS "LURK BENEATH THE OVERHANGING LEDGES OF THE ICE-FOOT, OUT OF SIGHT OF THE BIRDS OVERHEAD" (Page 84)]
At the place where they most often went in, a long terrace of ice about six feet in height ran for some hundreds of yards along the edge of the water, and here, just as on the sea-ice, crowds would stand near the brink. When they had succeeded in pus.h.i.+ng one of their number over, all would crane their necks over the edge (Fig. 44), and when they saw the pioneer safe in the water, the rest followed.
When diving into shallow water they fall flat (Figs. 45, 46, and 47), but into deep water, and from any considerable height, they a.s.sume the most perfect positions (Fig. 50) and make very little splash.
Occasionally we saw them stand hesitating to dive at a height of some twenty feet, but generally they descended to some lower spot, and did not often dive from such a height, but twelve feet was no uncommon dive for them.
The reluctance shown by each individual of a party of intending bathers to be the first to enter the water may partly have been explained when, later on, we discovered that a large number of sea-leopards were gathered in the sea in the neighbourhood of the rookery to prey on the penguins. These formidable animals, of which I show some photographs, used to lurk beneath the overhanging ledges of the ice-foot, out of sight of the birds on the ice overhead. (Fig. 51.) They lay quite still in the water, only their heads protruding, until a party of Adelies would descend into the water almost on top of them, when with a sudden dash and snap of their great formidable jaws, they would secure one of the birds.