Juan Fernandez fur seal
The Juan Fernandez fur seal (Arctocephalus philippii) is a marine mammal native to the Juan Fernandez Islands off the coast of Chile. Discovered in 1866, these seals are characterized by their stout bodies and coats of goldish gray fur. As eared seals, they possess small, rolled ears and are equipped with flippers that function both for swimming and moving on land. Adult males reach lengths of 4.5 to 6.5 feet and weigh around 300 pounds, while females are smaller, averaging 4.5 feet and 110 pounds.
These seals primarily inhabit the waters surrounding Juan Fernandez Island, Robinson Crusoe Island, and Alejandro Selrick Island, where they feed on small fish, squid, and rock lobsters. Social by nature, they breed on land during November and December, with males often competing for mates and forming harems. The gestation period lasts about a year, resulting in the birth of a single pup. Female seals use unique vocalizations to locate their young among hundreds of others. Despite their adaptive behaviors and secure breeding grounds, Juan Fernandez fur seals are classified as a near threatened species, facing risks from predators and human activities. Their lifespan averages 13 years for males and 23 years for females.
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Juan Fernandez fur seal
Juan Fernandez fur seals were first discovered off the coast of Juan Fernandez Island in 1866. The Juan Fernandez Islands are off the coast of Chile.
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Otariidae
Genus: Arctocephalus
Species: Philippii
Like other fur seals, Juan Fernandez fur seals are pudgy looking seals with coats of goldish gray fur. They have tail fins that help them swim in water and balance on land. They also have two flippers which they use to propel themselves through the water when they are swimming. These flippers also serve as legs when they are on rocky beaches. Juan Fernandez fur seals are eared seals. That means they have small, rolled ears that stick out on both sides of their heads. Juan Fernandez fur seals are very similar to South American fur seals, except they have smaller heads. Like all seals, Juan Fernandez seals have a layer of fatty tissue, called blubber, located right under their skin. This fat is used to keep the animals warm in colder waters and acts as a storage place for food. Male Juan Fernandez fur seals grow to be between 4 1/2 and 6 1/2 feet (1 1/4 to two meters) long and weigh about 300 pounds (135 kilograms). The females grow to be only about 4 1/2 feet (1 1/4 meters) long and weigh about 110 pounds (50 kilograms).
Juan Fernandez fur seals live in the waters around Juan Fernandez Island, Robinson Crusoe Island, and Alejandro Selrick Island. These three islands are in the south Pacific Ocean off the coast of Chile.
Juan Fernandez fur seals eat small fish, squid, and rock lobsters. While feeding at sea, Juan Fernandez seals often travel in small groups or alone. They are often found where the ocean current brings fish and other sea life up to the top of the water.
Juan Fernandez fur seals, like other eared seals, must come on land to breed. Because the eared seals are social breeders, the breeding grounds are very lively places during the breeding months. Often the males will fight with each other for mates. Successful breeding bulls, or males, have harems, or groups of female mates. The time of the mating season for Juan Fernandez fur seals is between November and December.
They have a gestation period (duration of pregnancy) of about one year. The female then gives birth to one pup, or young seal. Shortly after the pup is born, the female mates again. During the months following, the female travels out to sea to find food for herself and then goes back on land to feed her pup. When she comes back from one of her trips to sea, she finds her pup among the hundreds of others by yelling out her special pup-attraction call. The pup will recognize its mother's call and respond.
Eared seals protect themselves from predators such as human hunters, large sharks, killer whales, leopard seals, and polar bears by finding secure breeding grounds on land.
Juan Fernandez fur seals have a life span of about 13 years for males and 23 years for females. These seals are a near threatened species.
Bibliography
Handysides, Daniel. “ADW: Arctocephalus Philippii: Information.” Animal Diversity Web, 2004, animaldiversity.org/accounts/Arctocephalus‗philippii. Accessed 15 Apr. 2024.
“Juan Fernandez Fur Seal (Arctocephalus Philippii).” Seal Conservation Society, 2024, www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/juan-fernandez-fur-seal. Accessed 15 Apr. 2024.