Instantly recognisable by the large, inflatable proboscis, the male southern elephant seal is the biggest seal in its family. Males can weigh eight to ten times as much as females, making them the most sexually dimorphic of all mammals (2). Females do not have a proboscis, but rather a short nose and a muzzle (4). Both sexes have robust bodies, thick necks and broad heads, and each digit of the fore flippers bears a large, black nail (4). The coat is light to dark silvery-grey or brown in adults and juveniles, whilst newborns have black coats, which turns into a short silvery-grey coat at around three weeks of age (5). Males develop a chest shield of thickened, creased and heavily scarred skin as they age, and also become paler across the face, proboscis and head (4). During the breeding season, southern elephant seals become stained rusty orange and brown from lying in their own excrement.