This one shows the patches of dark skin peeling off, showing the brown coat beneath.
The black coat is also an indicator of maturity to Marine Mammal Center rescuers. Pups rescued before they molt get formula.
This blog records my experiences as a docent at the Piedras Blancas Elephant Seal Rookery on Highway 1 in California. Juvenile seals are on the beach, soon to be displaced by adult bulls returning for the breeding season.