Southern Elephant Seals (Mirounga Leonina) are the largest species of seals. They have a circumpolar range and can be found on most sub-Antarctic islands. Colonies in the Pacific and Southern Indian oceans have seen a marked decline over the last 50 years, with populations dropping by between a third to a half. These seals became a target for indiscriminate hunting from the late 1700’s through to the late 1800’s when it became no longer profitable to hunt them. It was possible to hunt these seals under licence from 1910 to 1964. Since then no hunting has been permitted as this CITES II listed species enjoys protection from both the Convention for the Protection of Antarctic Seals (s. of 60 degrees) and the Convention on Antarctic Marine Living Resources (n. of 60 degrees)
The breeding season begins with males coming to shore first in September. Here they will fight each other for territorial rights and the right to compete for females. These battles can get pretty intense as successful males can command a harem of up to 40 females! Younger males will hang around on the periphery in the hopes of unseating the dominant male or getting lucky with one of his females.
Females give birth shortly after arriving on shore and will mate with the Beach Master when her pup is around 18 days old. Larger females tend to give birth to male pups while smaller females tend to give birth to females.
Pups can weigh anything from 45-50kg and measure approximately 1.3m at birth. They suckle intensively and can gain as much as 9kg per day! The weaning process lasts for just short of a full month before the females return to sea, leaving the pups to fend for themselves.
Pups then gather together in small groups where they spend the vast majority of their time resting. Male pups may engage in mock fights or will snuggle up to females in the manner of adults mating. Pups fast for up to two months as they gradually develop the skills they need to survive. During this time they are sustained by their blubber reserves and may lose up to 30% of their body weight.
Southern Elephant Seals are the largest of all pinnipeds. Males can weigh a massive 3 700 kg and measure up to 5.8m in length. Females are by comparison quite small, weighing between 400 kg and 900 kg. Males reach sexual maturity at between 4-5 years, gaining territorial status when they are around 10. Females reach sexual maturity at around 4 years. They live for between 14 and 20 years.
Only the males have the extended proboscis. They use it to make trumpeting noises to attract females and declare territory.
While these seals tend to live in groups while on land, they prefer to hunt alone.
Only Killer Whales and Great White Sharks are large enough to prey on this species. (aside from man that is)
They were hunted to the brink of extinction but made a recovery due to strict enforcement of regulations. However, their limited gene pool has resulted in compromised immune systems.
Southern Elephant seals can hold their breath for over an hour and a half. This is the longest period known for any non-cetacean mammal. This is possible due to an extra large volume of blood.
The deepest recorded dive by a Southern Elephant Seal is …. 2 388 METERS!!!! That is over 2km underwater! Can you IMAGINE the pressure down there??
They feed on skates, rays, eels, small sharks, penguins and even other species of small seals
Depleted food stocks and global warming are cause for concern.