[4] It feeds on a wide range of prey including cephalopods, other pinnipeds, krill, fish, and birds, particularly penguins.

[10] The front teeth are sharp like those of other carnivores, but their molars lock together in a way that allows them to sieve krill from the water in the manner of the crabeater seal.

[11] Their hearing in air is similar to that of a human, but scientists have noted that leopard seals use their ears in conjunction with their whiskers to track prey under water.

[11] Fossil evidence suggests that leopard seals inhabited South Africa during the Late Pleistocene.

[19][11][20] These matrilineal groups can move further north in the austral winter to sub-antarctic islands and the coastlines of the southern continents to provide care for their pups.

[21] Lone male leopard seals hunt other marine mammals and penguins in the pack ice of antarctic waters.

This habit of submarine vocalizing makes leopard seals naturally suited for acoustic surveys, as are conducted with cetaceans, allowing researchers to gather most of what is known about them.

[25] Adult male leopard seals have only a few stylized calls, some are like bird or cricket-like trills yet others are low haunting moans.

These cadences of calls are believed to be a part of a long range acoustic display for territorial purposes, or to attract a potential mate.

[26] Conversely, a female leopard seal can attribute[clarification needed] calls to their environment as well; however, usually it is to gain the attention of a pup, after getting back from a forage for food.

Since leopard seals live in an area difficult for humans to survive in, not much is known on their reproduction and breeding habits.

The male leopard seal does not participate in taking care of the pup, and goes back to its solitary lifestyle after the breeding season.

[36] Around the sub-Antarctic island of South Georgia, the Antarctic fur seal (Arctocephalus gazella) is the main prey.

Additionally, this population of leopard seals and those in Australia were noted to bear wounds from chimaeriforms and stingrays respectively.

[38] 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.

Previous reports stating the leopard seal skins its prey before feeding have been found to be incorrect.

They use their front flippers similarly to sea lions (otariids)[40] and leopard seal females are larger than males.

[42] This information is sent to a satellite where scientists from anywhere in the world can collect the data, allowing them to learn more about leopard seals diet and foraging habits.

[47] In 1985, Canadian-British explorer Gareth Wood was bitten twice on the leg when a leopard seal tried to drag him off the ice and into the sea.

[46][45] On 26 September 2021, near the dive site Spaniard Rock at Simon's Town, South Africa, three spear-fishermen encountered a leopard seal while spearing approximately 400 m offshore.

The seal attacked them and, while they were swimming back to shore, disarmed them of their flippers and spearguns and kept harassing the men over the course of half an hour, inflicting multiple bite and puncture wounds.

[48] In 2003, biologist Kirsty Brown of the British Antarctic Survey was killed by a leopard seal while conducting research snorkeling in Antarctica.

[49] Leopard seals have shown a predilection for attacking the black, torpedo-shaped pontoons of rigid inflatable boats, leading researchers to equip their craft with special protective guards to prevent them from being punctured.

Because of their limited subpolar distribution in the Antarctic, they may be at risk as polar ice caps diminish with global warming.