This Pinnipednesday is kind of a two-fer. It might have been about the Japanese Sea Lion, if it had not gone extinct in the 1970s. It has not been observed since then. In 2007, South Korea, China and Russia announced a collaborative effort to search for any surviving population of Japanese Sea Lions. If this effort is not successful, then South Korea is looking into plans to relocate a population of California Sea Lions (of which the Japanese Sea Lion was long believed to be a subspecies) to the Sea of Japan in order to restore the ecological system.

Instead, this Pinnipednesday is about the Juan Fernandez Fur Seal (Arctocephalus philippii). It can be found on the Juan Fernandez islands off the coast of Chile, and is closely related to the Galapagos Fur Seal. To provide a somewhat happy counterpoint to the sad situation of the Japanese Sea Lion, the Juan Fernandez Fur Seal was believed to have gone extinct until a tiny surviving population was discovered in 1965. Though it has gained in population since then, it is still one of the rarest pinniped species today.

Adult male Juan Fernandez Fur Seals are nearly twice as big as adult females, and are much more stocky in their build. They have long snouts and are bulky in the neck and shoulders. They grow up to 7 feet (2.1 meters) in body length, and weigh about 350 pounds (159 kg). Females are slender and smaller, growing up to 5 feet in body length and weighing 110 pounds (50 kg). Males will typically grow a pale, silvery mane around their neck, while females are darker in color.

The diet of Juan Fernandez Fur Seals consists primarily of squid, different kinds of fish and crustaceans. When they haul out onto shore, it's usually on the rocky volcanic shorelines of the Juan Fernandez archipelago and the islands of San Ambrosio and San Felix. Like other pinniped species of the region, Juan Fernandez Fur Seals themselves are prey to various kinds of sharks and orcas.

Juan Fernandez Fur Seals live in groups that are male-dominated, and males are extremely territorial, defending their status not only on the land and around their family groups, but also in the water - which is unusual for pinnipeds. Breeding and pupping takes place from November to January. Females with pups will nurse them for a total of 8 to 12 months, and after the initial 11-day nursing period will make hunting forays that last for about 12 days and then come back to nurse their pups for about 5 days.

During the same period between the 17th and 19th centuries that saw the rapid decline in many pinniped populations, the Juan Fernandez Fur Seal nearly faced total extinction. By the accounts of sailors who first reported seeing them, there were millions of them. In 1965, a population of 200 survivors were found and immediately protected, and today they number about 10,000. They are still considered to be near threatened by the IUCN, and occasionally they are still illegally hunted.

Source for all images used in this post.