Leopard Seal

Common Name: Leopard Seal

Class: Mammalia

Order: Pinnipedia

Family: Phocidae

Genus: Hydrurga

Species: Hydrurga leptonyx



Leopard seals belong to the Mammalian Order Pinnipedia, in the family Phocidae.  Other members of Phocidae include elephant seals, gray seals, and monk seals.  Phocids are referred to as true seals.  They are distinguished from other pinnipeds by their inability to support their body using their hind limbs.  The leopard seal's scientific name is Hydrurga leptonyx.  The generic name, Hydrurga, refers to a "water driven lifestyle".  The specific name, leptonyx, means "smooth claw".  The leopard seal is easily recognized by its very reptilian head.  Their nostrils are located high on their snouts, and they do not have a distinct forehead.  Leopard seals are grayish with dark brown and gray spots.  Males reach lengths of 8-10 feet and weigh up to 900lbs.  Females reach lengths of 10-12 feet, weighing up to 1000lbs.


The leopard seal is found on the pack ice flows of Antarctica.  They seasonally haul out to islands nearer the continent in the summer months and  return to the subantarctic islands when the ice expands.  Some seals live near penguin rookeries, which is just one of many antarctic species that leopard seals hunt.  In fact, the leopard seal is the only seal species that regularly preys on warm-blooded animals.  Most leopard seal diets consist mainly of krill, fish, and squid.  But seabirds, penguins, and even other seal species are also common.  Some leopard seals prey predominantly on Adelie, Chinstrap, and Gentoo penguins, living close to rookeries.  Only the fleshy parts of the penguin are eaten.  This leaves the legs, head, skeleton, and flippers untouched.  Crabeater seals, Weddell seals, southern elephant seal pups, fur seals, and the Ross seal are all potential prey species for the leopard seal.  The crabeater seal is most commonly eaten.  The characteristic scarring on crabeater seals is often the result of leopard seal attacks.  The blubber and attached skin of the crabeater seal are only eaten by the leopard seal.


Leopard seals are aggressive hunters.  Despite the reputation achieved by preying on penguins and other seal species, attacks on human explorers have also been recorded.  Slow on land, leopard seals are extremely agile in water.  Elongated foreflippers allow the leopard seal to move faster in water than other seal species.  The leopard seal is the only phocid to use its foreflippers for swimming.  Some seals have even become proficient penguin hunters.  Penguins are well adapted to swimming, exhibiting very high maneuverability.  Leopard seals surprise their prey to overcome the penguins' superior speed and agility.

Leopard seals lead solitary lives.  During breeding season, pairs and small groups of leopard seals come ashore to breed.  After a nine month gestation period, a female leopard seal gives birth to a single pup, weighing over 65lbs.  She digs a small den to house her newborn pup.  Males reach sexual maturity at 2-6 years, while females mature sexually at 3-7 years.  Leopard seals live to about 25 years of age.  Their only natural predator is the killer whale.


The leopard seal population is estimated at about 250,000 individuals.  Due to the inaccessibility of Antarctica, this species is relatively free from human encroachment and habitat destruction.  However, one should not become complacent of the leopard seal's environment.


Content provided by Canisius College students under the direction of Michael Noonan, PhD.