Cows come ashore two days before giving birth. Cows lactate for 117 days. These seals are at a disadvantage when it comes to terrestrial predators. The eared seals are very social mammals. They congregate into groups, which become larger during the mating season.
Large size is favored for two reasons.
First a larger bull is stronger and can betterer defend his harem. Due to the strain put a successful bull, he is able to remain dominant for only 2-3 mating seasons. The Australian sea lion is found in cool but not cold waters in temperate and sub-temperate climates. They are generally coastal mammals, spending their time on beaches, offshore rocks, and islands. The Encyclopedia of Mammals.