Sea elephant

The elephant seal is a real seal, or a seal without ears, members of the pinniped suborder. These are amazing creatures: huge fat males with drooping noses, attractive females that seem to be constantly smiling, and adorable plump cubs with a huge appetite.

Origin of the species and description

Photo: Elephant Seal

Photo: Elephant Seal

The elephant seal is a deep-sea diver, a long-distance traveler, an animal that starves for long periods of time. Elephant seals are extraordinary, they come together on land to give birth, mate and molt, but at sea they are alone. Huge demands are placed on their appearance in order to continue their race. Studies show that elephant seals are the children of a dolphin and a platypus, or a dolphin and a koala.

Video: Elephant seal

Interesting fact: These massive pinnipeds are not called elephant seals because of their size. They got their name from the inflatable muzzles that look like an elephant's trunk.

The history of the development of the elephant seal colony began on November 25, 1990, when less than two dozen individuals of these animals were counted in a small bay south of the Piedras Blancas lighthouse. In the spring of 1991, almost 400 seals were bred. In January 1992, the first birth took place. The colony grew at a phenomenal rate. In 1993, about 50 cubs were born. In 1995, another 600 cubs were born. The population explosion continued. By 1996, the number of pups born had risen to nearly 1,000, and the colony extended all the way to the beaches along the coastal highway. The colony continues to expand today. In 2015, there were 10,000 elephant seals.

Appearance and Features

Photo: What a seal looks like

Photo: What a seal looks like

Elephant seals — sociable animals belonging to the Phocidae family. The northern elephant seal is yellowish or grey-brown, while the southern elephant seal is blue-gray. The southern species has an extensive molting period during which significant areas of hair and skin fall out. Males of both species reach a length of about 6.5 meters (21 feet) and weigh about 3,530 kg (7,780 pounds) and grow much larger than females, which sometimes reach 3.5 meters and weigh 900 kg.

Elephant seals reach speeds of 23.2 km/h. The largest of the 33 existing — southern elephant seal. Males can be over 6 meters long and weigh up to 4.5 tons. Harbor seals have a broad, round face with very large eyes. The pups are born with a black coat that sheds around the time of weaning (28 days) to a smooth, silvery gray coat. Within a year, the coat will turn a silvery brown.

Female elephant seals give birth for the first time around 4 years of age, although the range varies from 2 to 6 years. Females are considered physically mature at age 6. Males reach sexual maturity at about 4 years of age when the nose begins to grow. The nose is a secondary sexual characteristic, like a man's beard, and can reach an astonishing length of half a meter. Males reach physical maturity at about 9 years of age. The main breeding age is 9-12 years. Northern elephant seals live an average of 9 years, while southern elephant seals live between 20 and 22 years.

Humans shed their hair and skin all the time, but elephant seals go through a catastrophic molt in which the entire epidermal layer with attached hairs sticks together at one point in time. The reason for this abrupt molt is that at sea they spend most of their time in cold, deep water. In the process of immersion, blood moves away from the skin. This helps them conserve energy and not lose body heat. Animals swim to the ground when they molt so blood can circulate through the skin to help grow a new layer of epidermis and hair.

Where does the elephant seal live?

Photo: Southern Elephant Seal

Photo: Southern elephant seal

There are two types of elephant seals:

  • northern;
  • southern.

Northern elephant seals are found in the North Pacific from Baja California, Mexico to the Gulf of Alaska and the Aleutian Islands. During the breeding season, they live on beaches on offshore islands and in a few remote locations on the mainland. During the rest of the year, with the exception of periods of molting, elephant seals live far from the coast (up to 8000 km), usually descending to a depth of more than 1500 meters below the ocean surface.

Southern elephant seals (Mirounga leonina) live in subantarctic and cold Antarctic waters. They are distributed throughout the Southern Ocean around Antarctica and on most of the subantarctic islands. The population is concentrated on the Antipodean Islands and Campbell Island. In winter, they often visit the islands of Auckland, Antipodes and Snares, less often the Chatham Islands and sometimes various mainland areas. Occasionally, southern elephant seals visit local New Zealand mainland coastlines.

On the mainland, they may remain in the area for several months, giving people the opportunity to observe the animals that normally live in subantarctic waters. The grace and speed of such large marine mammals can be impressive, and young seals can be very playful.

Fun fact: Unlike most other marine mammals (such as whales and dugongs), elephant seals are not completely aquatic: they emerge from the water to rest, molt, mate, and give birth.

What does the elephant seal eat?

Photo: Female elephant seal

Photo: Female elephant seal

Elephant seals are carnivores. Southern elephant seals are predators of the open ocean and spend most of their time at sea. They feed on fish, squid or other cephalopods found in Antarctic waters. They come ashore only to breed and molt. The rest of the year is spent feeding in the sea, where they rest, swimming on the surface and diving in search of large fish and squid. During their time at sea, they often take them far from their breeding grounds and can travel very long distances between their time on land.

It is believed that their females and males feed on different prey. The female diet consists mainly of squid, while the male — more diverse, consisting of small sharks, rays and other bottom fish. In search of food, males travel along the continental shelf to the Gulf of Alaska. Females tend to head north and west to the more open ocean. The elephant seal makes this migration twice a year, also returning to the rookery.

Elephant seals migrate in search of food, spend months at sea and often dive deep in search of food. In winter, they return to their rookeries to breed and give birth. Although male and female elephant seals spend time at sea, their migration patterns and feeding habits differ: males take a more consistent route, hunting along the continental shelf and foraging on the ocean floor, while females change their routes in search of moving prey and hunt more in the open ocean. Lacking echolocation, elephant seals use their eyesight and their whiskers to sense nearby movement.

Personality and Lifestyle Features

Photo: Sea elephant in nature

Photo: Elephant seal in nature

Elephant seals come ashore and form colonies for only a few months of the year to give birth, breed and shed. During the rest of the year, the colonies disperse and individuals spend most of their time foraging, which means swimming thousands of miles and diving to great depths. While elephant seals are at sea in search of food, they dive to incredible depths.

They usually dive to a depth of about 1500 meters. The average dive time is 20 minutes, but they can dive for an hour or longer. When elephant seals come to the surface, they only spend 2-4 minutes on land before submerging again — and continue this diving procedure 24 hours a day.

On land, elephant seals are often left without water for long periods of time. To avoid dehydration, their kidneys can produce concentrated urine that contains more waste and less actual water in every drop. Rookery — a very noisy place during the breeding season, as males vocalize, call for babies to be fed, and females squabble with each other over excellent location and babies. Grunts, snorts, burps, whimpers, creaks, squeals and male roars combine to create a symphony of elephant seal sound.

Social Structure and Reproduction

Photo: Elephant Seal Baby

Photo: Elephant Seal Baby

The southern elephant seal, like the northern elephant seal, breeds and molts on land, but winters at sea, possibly near pack ice. Southern elephant seals breed on land but spend the winter in the cold waters of Antarctica near the Antarctic ice. The northern species does not migrate during the breeding process. When the breeding season comes, male elephant seals establish and defend territories, become aggressive towards each other.

They gather a harem of 40 to 50 females, which are much smaller than their huge partners. Males fight each other for mating dominance. Some encounters end in roars and aggressive posturing, but many others turn into violent and bloody battles.

The breeding season starts at the end of November. Females start arriving in mid-December and continue to arrive until mid-February. The first birth occurs around Christmas, but most births usually occur in the last two weeks of January. Females remain on the beach for about five weeks from the moment they land. Surprisingly, males stay on the beach for up to 100 days.

When breastfeeding, females do not eat — both mother and child live off the energy stored in her ample reserves of fat. Both males and females lose about 1/3 of their weight during the breeding season. Females give birth to one cub every year after 11 months of pregnancy.

Fun fact: When a female gives birth, the milk she secretes is about 12% fat. Two weeks later, this number increases to over 50%, giving the liquid a pudding-like consistency. By comparison, cow's milk contains only 3.5% fat.

Natural enemies of elephant seals

Photo: Elephant Seal

Photo: Elephant Seal

The great southern elephant seals have few enemies, among them:

  • killer whales, which can prey on cubs and old seals;
  • leopard seals, which sometimes attack and kill their cubs;
  • some large sharks.

Elephant seals can also be considered enemies during breeding season. Elephant seals form harems in which the dominant or alpha male is surrounded by a group of females. On the periphery of the harem, beta males wait in hopes of mating opportunities. They help the alpha male keep less dominant males. Fighting between males can be a bloody affair, with the males getting to their feet and smashing themselves against each other with their big canine teeth.

Elephant seals use their teeth during combat to tear the neck of opponents. Large males can be severely injured from fighting with other males during the breeding season. Fights between dominant males and challengers can be long, bloody, and extremely violent, with the loser often suffering serious injury. However, not all confrontations end in battle. Sometimes it is enough for them to rear up on their hind limbs, throw back their heads, show off the size of their noses and roaring threats to intimidate most opponents. But when there are battles, it rarely comes to death.

Population and Species Status

Photo: What elephant seals look like

Photo: What elephant seals look like

Both species of elephant seals were hunted for their blubber and were nearly wiped out in the 19th century. However, under legal protection, their numbers are gradually increasing, and their survival is no longer threatened. In the 1880s, northern elephant seals were thought to be extinct, as both species were hunted by coastal whalers for their blubber, which is second only to sperm whale blubber. A small group of 20-100 elephant seals that were bred on Guadalupe Island, off Baja California, survived the devastating results of a seal hunt.

Protected first by Mexico and then by the United States, they are constantly expanding their population. Protected by the Marine Mammal Protection Act of 1972, they are expanding their range away from the outlying islands and are currently colonizing isolated mainland beaches such as Piedras Blancas in the southern part of Big Sur, near San Simeon. The total population estimate for elephant seals in 1999 was about 150,000.

Fun fact: Elephant seals are wild animals and should not be approached. They are unpredictable and can cause great harm to humans, especially during the breeding season. Human interference can cause seals to use up precious energy needed to survive. Cubs can be separated from their mothers, often resulting in their death. The National Marine Fisheries Service, the federal agency responsible for enforcing the Marine Mammal Protection Act, recommends a safe viewing distance of 15 to 30 meters.

The elephant seal is an amazing animal. They are large and bulky on land, but excellent in the water: they can dive to a depth of 2 kilometers and hold their breath underwater for up to 2 hours. Elephant seals move throughout the ocean and can swim great distances in search of food. They fight for a place under the sun, but only the most courageous achieve the goal.

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