A growling leopard seal
The leopard seal is large and muscular, with a dark grey back and light grey on its stomach. Its throat is whitish with the black spots that give the seal its common name. Females are generally slightly larger than the males on average. The bulls are generally 2.5"?3.2 m (8.2"?10 ft) and weigh between 200 and 453.5 kg (440 and 1,000 lb), while cows are between 2.4 and 3.4 m (7.9 and 11 ft) in length and weigh between 225 and 591 kg (500 and 1,300 lb).
Compared to most phocids, the Leopard seal is highly evolved for its role as apex predator. Although it is a true seal and swims with its hind limbs, it has powerful and highly developed forelimbs similar to sea lions, giving it a similar maneuverability, a classic example of convergent evolution. Like these eared seals, the Leopard Seal is a shallow water hunter, and does not dive deep like the other seals of the Antarctic (the Weddell seal, the Ross seal and the two species of elephant seals) which can all dive to several hundred meters in search of squid. The leopard seal has an unusually loose jaw that can open more than 160 degrees allowing it to bite larger prey.
Like most carnivores, its front teeth are sharp, but its molars lock together in a way that allows them to sieve krill from the water, similar to the Crabeater seal.
The leopard seal lives in the cold waters surrounding Antarctica. During the summer months, it hunts among the pack ice surrounding the continent, spending almost all of its time in the water. In the winter, it ranges north to the sub-Antarctic islands. Occasionally, individuals may be spotted on the southern coasts of South America, Australia, and New Zealand, and as far north as the Cook Islands. Juveniles are more often found in the north.
The leopard seal is a solitary creature and comes together in small groups only when it is time to mate. The female digs a hole in the ice and, after a nine month gestation, gives birth to a single pup during the Antarctic summer. She protects the pup until it is able to fend for itself.
They are very quiet except for some grunting and growling noises.
The leopard seal is bold, powerful and curious. In the water, there is a fine line between curiosity and predatory behavior, and it may 'play' with penguins that it does not intend to eat.
A leopard seal feeding on a gentoo penguin
The leopard seal is the Antarctic's equivalent of the polar bear and is the top predator on the continent. It has canine teeth that are 2.5 cm (1 in). It feeds on a wide variety of creatures. Smaller seals probably eat mostly krill, but also squid and fish. Larger leopard seals probably switch to feed on King and Emperor Penguins , and, less frequently, other seals such as the crabeater seal.
Around the sub-Antarctic Island of South Georgia the Antarctic fur seal (Arctocephalus gazella) is the main prey. Other prey includes penguins and fish. Antarctic krill (Euphausia superba), southern elephant seals (Mirounga leonina) and seabirds other than penguins have also been found in Leopard seal scats in small quantities.
When hunting penguins, the leopard seal patrols the waters near the edges of the ice, almost completely submerged, waiting for the birds to enter the ocean. It kills the swimming bird by grabbing the feet, then shaking the penguin vigorously and beating its body against the surface of the water repeatedly until the penguin is dead. Previous reports stating that the leopard seal skins its prey prior to feeding have been found to be incorrect. Lacking the teeth necessary to slice its prey into manageable pieces, it flails its prey from side to side in order to tear and rip it into smaller pieces.
Attacks on humans
Leopard seals are potentially highly dangerous towards humans, but attacks are rarely reported. Examples of aggressive behavior, stalking and attacks have been documented, notable incidents include:
- A large leopard seal attacked Thomas Orde-Lees (1877 "? 1958), a member of Sir Ernest Shackleton's Imperial Trans-Antarctic Expedition of 1914"?1917 when the expedition were camping on the sea ice. A large "sea leopard" of approximately 12 feet long and 1,100 pounds chased Orde-Lees on the ice. He was only saved when another member of the expedition shot the animal.
- In 1985, Scottish explorer Gareth Wood was bitten twice on the leg when a leopard seal tried to drag him off the ice and into the sea. His companions managed to save him by repeatedly kicking the animal in the head with the spiked crampons on their boots.
- In 2003, a leopard seal dragged snorkeling biologist Kirsty Brown of the British Antarctic Survey underwater to her death, in what was identified as the first known human fatality from a leopard seal.
Leopard seals have previously shown a particular predilection for attacking the black, torpedo-shaped pontoons of rigid inflatable boats, necessitating that researchers equip their craft with special protective guards to prevent them from being punctured.
- Australian Marine Mammal Research Centre