Interactions between humans and leopard seals

In July 2003 Kirsty Brown, a marine biologist at Rothera Research Station (West Antarctic Peninsula), was attacked and drowned by a leopard seal (Hydrurga leptonyx). As a direct consequence, a study was initiated to analyse interactions between humans and leopard seals over the last thirty years utilising humanistic and observational data. The response of leopard seals to humans in different situations was considered using a categorical response scale. Location of the leopard seal and human had the greatest influence on the response of the leopard seal. More specifically, interactions occurring at the ice edge, where leopard seals seek out prey, resulted in the highest response from leopard seals. ‘In water’ interactions, examined through SCUBA dive and snorkelling logs, generally described the seal’s behaviour as displaying curiosity and occurred most frequently at the surface. Although leopard seals approached close to observers and displayed behaviour that appeared aggressive, there were no records of interactions where ‘curious’ leopard seals showed subsequent hunting, or attack behaviour. In contrast, in most interactions (only a few occasions) where physical contact was initiated by a seal, in the form of an attack, the seal was not seen prior to the attack. Kirsty’s incident is the only known account of its kind, given that physical contact occurred at the surface of the water, and the seal had not been seen prior to the attack. This suggests that the commonly cited descriptions of leopard seals interacting with humans in the water are a distinctly different behaviour to that displayed in the attack on Kirsty. Although leopard seal behaviour was generally described by divers as curious, the death of Kirsty Brown indicates that leopard seals can display predatory behaviour towards humans.