Ingo Arndt / Antarctic Petrel (Thalassoica antarctica) flying, Weddell Sea, Antarctica

Frederique Olivier / Antarctic Petrel (Thalassoica antarctica) in flight, Antarctica.

Frederique Olivier / Antarctic Petrel (Thalassoica antarctica) taking off, running along sea surface, Antarctica

Frederique Olivier / Antarctic Petrel flock (Thalassoica antarctica) landing on iceberg, Antarctica

Tui De Roy / Antarctic petrel (Thalassoica antarctica), Antarctic Fulmar (Fulmarus glacialoides) and Pintado petrel (Daption capensis) flying, Antarctica, October.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) group flying over Southern Ocean, East Antarctica, October.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) flying over Southern Ocean, East Antarctica, October.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) flying over Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) flying over Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) flying over Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) flying over Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) flying, Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) on Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) taking off, Southern Ocean, Antarctica, November.

Tui De Roy / Antarctic petrel (Thalassoica antarctica) and Pintado petrel (Daption capensis) flying, Antarctica, October.

Tui De Roy / Antarctic petrel (Thalassoica antarctica), Antarctic fulmar (Fulmarus glacialoides) and Pintado petrel (Daption capensis) flying, Antarctica, October.

E.J. Peiker / Antarctic Petrel (Thalassoica antarctica) flying, Antarctica

Brent Stephenson / Antarctic petrel (Thalassoica antarctica) in fresh plumage against a blue sky, showing the upperwing. Drake Passage, South Atlantic. December.

E.J. Peiker / Antarctic Petrel (Thalassoica antarctica), Antarctica

Brent Stephenson / Antarctic petrel (Thalassoica antarctica) in flight, showing upperwing, Drake Passage, South Atlantic, December.

Brent Stephenson / Antarctic Petrel (Thalassoica antarctica) in flight, showing upperwing. Drake Passage, South Atlantic, December.

Brent Stephenson / Antarctic Petrel (Thalassoica antarctica) in flight, showing upperwing. Drake Passage, South Atlantic, December.

Tui De Roy / Antarctic Petrel (Thalassoica antarctica) flock flying, Southern Ocean, eastern Antarctica

Tui De Roy / Antarctic Petrel (Thalassoica antarctica) flock flying, Southern Ocean, eastern Antarctica

Ole Jorgen Liodden / Antarctic Petrel (Thalassoica antarctica) in flight over water. Southern Ocean, Antarctica, November.

Ole Jorgen Liodden / Antarctic Petrel (Thalassoica antarctica) in flight over breaking waves. Southern Ocean, Antarctica, November.

Pete Oxford / Aerial view of nesting colony of Antartic petrel (Thalassoica antarctica) Scullin island, Antarctica.

Mike Parry / Great White Shark (Carcharodon carcharias) attacking an Antarctic Petrel (Thalassoica antarctica), Dyer Island, Cape Province, South Africa

Hanne & Jens Eriksen / Antarctic petrel {Thalassoica antarctica} in flight over sea, Drake Passage, Antarctica

Pete Oxford / Antarctic petrel (Thalassoica antarctica) nesting pair, Scullin island, Antarctica.

Tui De Roy / Antarctic Petrel (Thalassoica antarctica) overlooking cliff-side nesting colony with 157,000 pairs, Scullin Monolith, Mawson Coast, east Antarctica

Tui De Roy / Antarctic Petrel (Thalassoica antarctica) flying near Enderby Island, New Zealand

Pete Oxford / Antarctic petrel in flight. Scullin Island, Antarctica.

Russell Laman / Emperor penguins (Aptenodytes forsteri) and Adelie penguins (Pygoscelis adeliae) resting on an iceberg with Antarctic petrels (Thalassoica antarctica) in flight overhead, Cape Colbeck, Ross Sea, Antar...

Frederique Olivier / Large flock of Antarctic petrels (Thalassoica antarctica) roosting on an iceberg, Antarctica, 2017.

Frederique Olivier / Antarctic petrel (Thalassoica antarctica) flying over calm sea, Antarctica.