Northern elephant seal, Southern elephant seal
Elephant seals are large seals that live in the ocean, of which there are two species, both of which were hunted almost to extinction by the close of the 19th century. The numbers have recovered since. One is the Northern elephant seal and the other is the Southern elephant seal, the latter being larger then its northern relative. These animals are huge when compared with other pinnipeds. They get their name from the adult male's large proboscis, which looks like an elephant's trunk. The Southern elephant seal has a coat that is light to dark silvery-gray or brown, while the Northern elephant seal is colored dark brown to light tan. Their ears are small holes.
The Northern elephant seal inhabits the Pacific coast of Mexico, the U.S. and Canada. Race Rocks is the most northerly breeding area on the Pacific Coast, at the southern end of Vancouver Island's Strait of Juan de Fuca. The seals inhabit gravel or sandy beaches, far away from human activity, as their preferred places for breeding. When at sea, males tend to feed over continental shelves, while females prefer deeper open water. Southern elephant seals are found on big and small islands along the coasts of South Africa, New Zealand, Argentina and Chile. During the breeding season, these seals are generally found on rocky terrain and beaches, and sometimes on snow and ice. They live in the open ocean during the non-breeding season.
Habits and lifestyle
Most of the time they are moving about, migrating while they are foraging for food. Both males and females spend time at sea but their feeding habits and migration routes differ: males will follow a route that is more consistent, while females will vary their route in pursuit of prey. Elephant seals when in the water are solitary in nature, but they come together on the shore during mating season. There is a social hierarchy during the mating season, but males are less aggressive with each other when they come to land for molting. The nose of a male acts as a kind of re-breather, and is full of cavities designed to reabsorb the moisture from the seal's exhalations. During the mating season this is important, as the seals remain on the beach and do not feed, and so need to conserve body moisture because there is no incoming water.
pod, bob, harem, herd, rookery, colony
Diet and nutrition
Elephant seals eat fish and squid.
Elephant seals are polygynous, and each dominant male is in control of mating access to a group of females. The male’s proboscis is used to produce extremely loud roaring noises, particularly during the mating season. Northern elephant seals haul out for birthing and breeding from December to March, while their southern relatives breed in August to late November. After a gestation period of 7-9 months for Southern elephant seals and 10-12 months for Northern elephant seals, a single pup is born. Pups are generally weaned at around 20-27 days, when the female will remain with her new pup, giving it large quantities of fatty, rich milk, relying on the thick blubber of her body for sustenance. Elephant seals gain sexual maturity from 2 to 10 years of age.
7-9 and 10-1
Northern elephant seals suffer today from significant absence of genetic diversity in their populations, the result of drastic reductions in the past. The result of this may be that the northern elephant seal is ill equipped to cope with any changes in its environment. The main threat to these animals is large-scale fisheries, potentially competing with them for their preferred prey.
According to the IUCN Red List, the population size of Northern elephant seals in 2010 was estimated at between 210,000 and 239,000 animals. There is no recent comprehensive estimate of Southern elephant seal abundance. In 1990s, the population of Southern elephant seals was estimated to be between 664,000 and 740,000 animals. Elephant seals are currently classified as Least Concern (LC) on the IUCN Red List of threatened species.
Fun facts for kids
- Southern elephant seals are able to dive to over 4,921 feet (1,500 meters) and remain underwater for as long as two hours.
- When foraging, the dive depth of the Northern elephant seal averages 500 to 600 m (1,640 - 1,970 ft), but it is able to dive to as much as 1,500 m (4,920 ft) and stay under water for over 1 hour.
- Seals have many whiskers, called “vibrissae”, which help them locate prey in deep or murky water. Though they appear to have no ears, in fact, they have small ear holes which function well when they are both in water and on land.
- The bodies of these seals contain a lot of blood, which helps them to stay deep down in the ocean for a much longer time because their blood holds a high volume of oxygen which helps them when they dive.
- Despite their massive size, elephant seals are not slow. On the contrary, they are very good swimmers. If you see an elephant seal coming towards you from a distance, run quickly to safety, as on sand dunes they can move more quickly than humans.