Antarctic fur seals are one of the better-studied Southern Ocean predators. However, the vast majority of information has been collected during summer breeding months. The breeding system of the Antarctic Fur Seal is polygynous, and dominant breeding males mate with as many as 20 females during a successful season. Males establish breeding grounds in October to early November. Females generally reach the colonies in December and give birth to a single pup several days later. Gestation lasts between 8 and 9 months and it has been observed a high breeding synchrony across the species’ range, concentrating 90% of pup births in a 10-day window. Pups are weaned at about four months old. Juveniles may then spend several years at sea before returning to begin their breeding cycles.