Michael Pitts / Gentoo penguins (Pygoscelis papua) calling and defending their eggs from Southern Skua (Stercorarius antarcticus) hunting for unattended eggs or chicks, Sea Lion island, The Falklands, South Atlantic.

Ashley Cooper / Brown skua (Stercorarius antarcticus) on the beach on Prion Island, South Georgia, Southern Ocean.

Tony Heald / Brown skua (Stercorarius antarcticus) resting on tussock grass. Right Whale Bay, South Georgia. September.

Tony Heald / Brown skua (Stercorarius antarcticus), two fighting over carrion whilst standing in sea. South Georgia. September.

Heike Odermatt / Antarctic Skua (Catharacta antarctica) predating egg from Gentoo Penguin (Pygoscelis papua) nest, Sealion Island, Falkland Islands

Tui De Roy / Northern Rockhopper Penguin (Eudyptes moseleyi) with Brown skua (Stercorarius antarcticus) Gough and Inaccessible Islands UNESCO World Heritage Site, South Atlantic.

Frederique Olivier / Brown skua (Stercorarius antarcticus) perched above an Eastern rockhopper penguin (Eudyptes chrysocome filholi) nesting colony, Macquarie Island, Australian Antarctica.

Frederique Olivier / Brown skua (Stercorarius antarcticus) landing in an Eastern rockhopper penguin (Eudyptes chrysocome filholi) nesting colony, Macquarie Island, Australian Antarctica.

Frederique Olivier / Eastern rockhopper penguins (Eudyptes chrysocome filholi) reacting to a Brown skua (Stercorarius antarcticus) landing in their nesting colony, Macquarie Island, Australian Antarctica.

Frederique Olivier / Two Brown skuas (Stercorarius antarcticus) scavenging, Macquarie Island, Australian Antarctica.

Frederique Olivier / Three Brown skuas (Stercorarius antarcticus) scavenging, Macquarie Island, Australian Antarctica.

Frederique Olivier / Group of King penguins (Aptenodytes patagonicus) on a beach, with a Brown skua (Stercorarius antarcticus) in the foreground, Macquarie Island, Australian Antarctica.