From the time when they first went to the sea to feed until the end of the season, there was a continual stream of penguins ascending and descending the berg. As I watched them through glasses I saw that they had worn deep paths in the snow from base to summit. They had absolutely nothing to gain by going to all this trouble but the pleasure they seemed to derive from the climb, and when at the top, merely had a good look round and came down again.
Fig. 62. A COUPLE WITH THEIR CHICKS
When the birds were arriving at the rookery I watched for those who were to nest up the cliff, and several times saw birds on arriving at the rookery make for the heights without any hesitation, threading their way almost in a straight line through the nests to the screes at the bottom of the cliff, and up these to one or other of the paths leading up its side. Probably these had been hatched there, or had nested there before, and were making their way to their old haunts, but my notes on their nesting habits go to show that the cocks, at any rate, cannot keep to the same spot during successive years. It is the hen who chooses the site, and stays on it, as I have shown, until a mate comes to her, and wins her, very often only after defeating many other competitors.
The waste of life in an Adélie rookery is very great, and is due to the following causes:
- The eggs.
- Skuas.
- Cocks fighting among the nests.
- Floods from thaw water.
- Death of parents.
- Snow-drifts.
- Landslides.
- The young chicks.
- Adults.
- Sea-leopards.
- Landslides.
- Snow-drifts.
In the above lists I have made no mention of the wanton depredations committed—owing to the licence given to ignorant seamen—by expeditions which visit the Antarctic from time to time, but as these visits are made at rare intervals, they cannot greatly affect the population.
Fig. 63. ADÉLIE PENGUINS HAVE A STRONG LOVE OF CLIMBING FOR ITS OWN SAKE