Hombron JB and H. Jacquinot published in 1842 under the name Phoca carcinophaga seal design according to the skin and skull of an individual collected between the South Sandwich Islands and South Orkneys by the corvettes Astrolabe and Zealous between 1837 and 1840 under the command of Dumont d'Urville. In 1853, H. Jacquinot and J. Pucheran published a description of the crabeater seal referred to as Lobodon carcinophaga because Gray in 1844 had created the kind Lobodon. The genus name comes from the Greek lobos "lobe" and Odus "tooth" in reference to the lobed morphology of some of these teeth. Its specific name also comes from the Greek karkinos meaning "crab" and phagein meaning "eater" because it was believed that the pinniped ate only crab, which is totally false. At the time it was thought that because of the color red shells found in feces on the ice, in fact it was skin krill, not crabs. The name of crabeater seal is kept, but we now know that it does not eat nearly that krill.

The crabeater seal is the most abundant pinniped in the world. It is estimated the population to 13 million, which represents a figure greater than all other species of seals. Its distribution extends all around the Antarctic continent. It is found in large numbers during the austral summer in the west of the Peninsula (Graham Land) and in the southern part of the Ross Sea.

This seal can be up to 2m60 and weigh up to 225 kg. Females are generally larger than males. The body is relatively slim, sleek and streamlined shape. The head features an elongated snout, slightly pointed up or snout-shaped, the corners of the mouth are horizontal. The fur is brown, creamy white uniform. The animal is often covered with scars (about 63% of individuals) left by the attacks of Leopard Seal, as in this picture.

Monogamous for this species, the female begins to breed at the age of 3 years, the mature male is between 3 and 6 years. Parturition occurs primarily in mid-October on the drift ice in an area of ​​50 m radius defended by the male. The lactation period is very short (4 weeks). Mating takes place at weaning, perhaps on the ice.

The maximum age recorded in this species is 29 years, but it is believed that longevity could be at least 35 years. The only predators are crabeater seal leopard seals and especially the Orcs. It was operated during the campaign of the Norwegian seal hunt in 1964. Currently, the crabeater seal undergoes no human exploitation, especially protected by the Convention for the Protection of Antarctic seals.