In the water the Adelie penguins move rapidly and circle in the same way as a porpoise or dolphin, for which they are easily mistaken at a little distance. On level ice or snow they can get along about as fast as a man at a smart walk, but they find even a small crack a serious obstruction, and pause and measure with the eye one of a few inches before very cautiously hopping over it. They flop down and toboggan over any opening more than a few inches wide. Very rarely they swim in the water like ducks, and on these infrequent occasions their necks are below the surface and their heads are just showing.
The Adelie shows true courage in the breeding-season, for after he has learned to fear man he remains to defend the nest against any odds. When walking among the nests one is assailed on all sides by powerful bills, and for protection we wore long felt boots reaching well above the knee. Some of the clever ones, however, realised that they were wasting their efforts on the boots, and coming up behind would seize the skin above the boot and hang on tight, beating with their wings.
Some birds became so greatly interested in the camp that they wanted to nest there. One bird (we believe it was always the same one) could not be kept away and used to come every day, until at last he was carried away by Brocklehurst, a wildly struggling, unconquerable being.
The old birds enjoy play, while the young ones are solely engaged in satisfying the enormous appetites they have when growing. While the Nimrod was frozen in the pack some dozens of them disported themselves in a sea-pool alongside. They swam together in the duck fashion, then at a squawk from one they all dived and came up at the other side of the pool.
Early in October they began to arrive at the rookery, singly or in pairs. The first to come were the males, and they at once began to scrape up the frozen ground to make hollows for nests, and to collect stones for the walls with which they surrounded them.
An Adelie calling for a Mate after commencing the Nest.
(See page 242)
When the rookery is pretty well filled, and the nest-building is in full swing, the birds have a busy and anxious time. To get enough suitable small stones is a matter of difficulty, and may involve long journeys for each single stone, so the temptation is too strong for some of the birds, and they become habitual thieves. The bearing of the thief, however, clearly shows that he knows that he is doing wrong, for very different is his furtive look, even after he is quite out of danger of pursuit, from the expression of the honest penguin coming home with a hard-earned stone.
A thief, sitting on its own nest, was stealing from an adjacent nest, whose honest owner was also at home but looking unsuspectingly in another direction. Casually the latter turned his head and caught the thief in the very act, whereupon the culprit dropped the stone and pretended to be busy picking up an infinitesimal crumb from the neutral ground. Undoubtedly then the penguin has a conscience, at least a human conscience, that is the fear of being found out.
This stone-gathering is a very strong part of the nesting instinct, and even if at a late stage the birds lost their eggs or their young, they began again, in a half-hearted way, to heap up stones. Unmated birds occupied the fringe of the rookery, and amused themselves piling and stealing till the chicks began to hatch out.