April – May
Adult females that left the rookery after weaning their pups, as well as juveniles that were out at sea all winter, begin arriving late in March. This is the start of the molting season. Growing new skin at sea would cause a tremendous heat loss. Instead, they come ashore to grow a new layer of skin and hair cells, as the old layer falls off in patches.
The seals sometimes look like they have a skin disease, but this is a normal, yearly process. The seals don’t scratch or rub the old skin off; they just let it happen. They may move to and from the damp shore sand as the day warms and cools. Males may play-fight (spar) with each other in or out of the water, but there is little other activity.
