It was a splendid sight to watch the birds sailing in the high winds of Adelie Land. In winds of fifty to seventy miles per hour, when with good crampons one had to stagger warily along the ice-foot, the snow petrels and Antarctic petrels were in their element. Wheeling, swinging, sinking, planing and soaring, they were radiant with life—the wild spirits of the tempest. Even in moderate drift, when through swirling snow the vistas of sea whitened under the flail of the wind, one suddenly caught the silver flash of wings and a snow petrel glided past.
But most memorable of all were certain winter mornings of unexpected calm, when ruddy clouds tessellated the northern sky and were mirrored in the freezing sea. Then the petrels would be en fete, flying over from the east following the line of the Barrier, winding round the icy coves, darting across the jutting points and ever onward in their long migration. In the summer they flew for weeks from the west—a never-ending string of snow, silver-grey and Antarctic petrels, and Cape pigeons. The silver-grey petrels and Cape pigeons were only abroad during that season and were accompanied by skua gulls, giant petrels, Wilson petrels, and penguins. The penguins remained in Adelie Land for the longest period—almost six months, the skua gulls and giant petrels for five months, and the rest for a shorter period—the tolerable season of midsummer.
Birds that haunt the wide oceans all make use of the soaring principle in flight, some much more than others. The beautiful sliding sweep of the albatross is the most familiar example. With wings outspread, it is a miniature aeroplane requiring no engines, for the wind itself supplies the power. A slight movement of the tail-feathers and wing-tips controls its balance with nice precision. Birds employing this method of flight find their home in the zone of continuous steady winds which blow across the broad wastes of the southern seas.
Many petrels on the wing were shot during the winter. Laseron, who prepared the skins of our Adelie Land collection, determined, in the case of a number of specimens, the ratio of weight to horizontal area exposed to the wind. This subject is one which has lately exercised the curiosity of aviators. The ratios are those evolved by nature, and, as such, should be wellnigh perfect. Below is appended a table of the results obtained.
WEIGHT OF CERTAIN ANTARCTIC BIRDS IN RELATION TO WING AREAS
(Stated in pounds per square foot of wing surface)
Each is the mean of several determinations by Laseron
Giant petrel........... 3.5
Albatross ........... 2.4
Antarctic petrel......... 2.1
Skua gull ........... 1.6
Snow petrel ........... 1.1
Wilson petrel........... 0.6
Values from a book of reference quoted for comparison
Bat ........... 0.1
Sparrow ........... 0.4
Wild goose ........... 1.7
During the winter, for a long period, no seals ventured ashore, though a few were seen swimming in the bay. The force of the wind was so formidable that even a heavy seal, exposed in the open, broadside-on, would be literally blown into the water. This fact was actually observed out on the harbour-ice. A Weddell seal made twelve attempts to land on a low projecting shelf—an easy feat under ordinary circumstances. The wind was in the region of eighty-five miles per hour, and every time the clumsy, ponderous creature secured its first hold, back it would be tumbled. Once it managed to raise itself on to the flat surface, and, after a breathing spell, commenced to shuffle towards the shelter of some pinnacles on one side of the harbour. Immediately its broad flank was turned to the wind it was rolled over, hung for a few seconds on the brink, and then splashed into the sea. On the other hand, during the spring, a few more ambitious seals won their way ashore in high winds; but they did not remain long in the piercing cold, moving uneasily from place to place in search of protecting hummocks and finally taking to the water in despair. Often a few hours of calm weather was the signal for half a dozen animals to land. The wind sooner or later sprang up and drove them back to their warmer element.
Under the generic name, seal, are included the true or hair seals and the sea-bears or fur seals. Of these the fur seals are sub-polar in distribution, inhabiting the cold temperate waters of both hemispheres, but never living amongst the polar ice. The southern coast of Australia and the sub-antarctic islands were their favourite haunts, but the ruthless slaughter of the early days practically exterminated them. From Macquarie Island, for example, several hundred thousand skins were taken in a few years, and of late not a single specimen has been seen.