The leopard seal (Hydrurga leptonyx) is a large, powerful predator inhabiting the frigid waters of the Antarctic and sub-Antarctic regions. As the second largest seal species in Antarctica, it has a distinctive and formidable appearance. Its long, slender body, large head, and impressive mouth contribute to its reputation as a dominant predator in the polar ecosystem.
Natural Diet and Predatory Habits
Leopard seals are opportunistic and versatile hunters, consuming a wide variety of prey. Their diet includes small crustaceans like krill, fish, and cephalopods such as squid. As they mature, their prey expands to include warm-blooded animals like various penguin species and the pups of other seals, such as crabeater and Antarctic fur seals.
They employ diverse hunting techniques, including ambushing penguins at the ice edge or stalking prey with only nostrils exposed. Another tactic is a “wait and rush” approach. When capturing larger prey, leopard seals lack shearing teeth, so they thrash and shake their catch to break it into manageable pieces, often against the water’s surface.
Documented Interactions with Humans
Interactions between leopard seals and humans are rare, but documented incidents highlight their predatory capabilities. The most widely known event occurred in 2003 when British marine biologist Kirsty Brown was fatally attacked. While snorkeling for research near Rothera Research Station in Antarctica, Brown was pulled underwater and drowned. This marked the first recorded human fatality attributed to a leopard seal.
Earlier expeditions also described aggressive encounters. During Ernest Shackleton’s 1914-1917 Imperial Trans-Antarctic Expedition, Thomas Orde-Lees was chased across sea ice by a leopard seal. In 1985, Canadian-British explorer Gareth Wood was bitten on the leg and nearly dragged into the sea. While attacks are infrequent, these documented cases underscore the potential danger.
Understanding Attack Triggers
Several factors may contribute to rare aggressive encounters between leopard seals and humans. Misidentification is one possibility; seals might mistake humans, especially those in dark wetsuits, for natural prey like penguins or other seals. Humans standing vertically on ice, similar to penguins, may also be perceived as prey.
Leopard seals are naturally curious animals, and not all close interactions are aggressive. However, their curiosity can sometimes manifest in behaviors humans perceive as threatening, especially if they feel their territory is invaded or perceive a threat. Encounters at the ice edge, where seals actively hunt, can elicit higher responses.
Staying Safe in Their Habitat
Individuals venturing into leopard seal habitats should adhere to specific safety guidelines. Maintaining a safe distance from these animals is recommended, typically 5 to 20 meters. Sudden movements should be avoided, as they might startle or provoke a seal.
Approaching or attempting to feed a leopard seal is not advisable; it can alter their natural behavior and lead to dangerous situations. Understanding their body language, such as gaping or hissing, signals agitation and indicates a need to retreat slowly. Following instructions from experienced guides and researchers is recommended to minimize risks.