David Tipling / Snow petrel (Pagadroma nivea nivea) flying around Iceberg off South Georgia, Southern Ocean January

Brent Stephenson / Northern giant petrel (Macronectes halli) moving through water, off Kaikoura, Canterbury, New Zealand, November.

Ernie Janes / Fulmar (Fulmaris glacialis) in flight with Hunstanton, Norfolk, England, UK, February.

Tui De Roy / White-vented storm petrel (Oceanites gracilis galapagoensis) 'walking' on surface of water whilst foraging, Galapagos

Graeme Guy / Pintado Petrel (Daption capense) flying, South Island, New Zealand

Bryan and Cherry Alexander / Emperor penguins (Aptenodytes forsteri) colony, with Snow petrel (Pagodroma nivea) flying past and dark sky. Atka Bay. Antarctica

Bryan and Cherry Alexander / Chinstrap penguins (Pygoscelis antarctica) on a blue iceberg, with Antarctic Prion (Pachyptila desolata) flying over. Antarctica

Chris & Monique Fallows / Pintado petrel (Daption capense) flying in snow, Southern Ocean.

Chris & Monique Fallows / Pintado petrel (Daption capense) flock in flight, Southern Ocean.

Theo Bosboom / Fulmar (Fulmarus glacialis) above snowy lava beach near Djupivogur in the East of Iceland, March

Barrie Britton / Southern Giant Petrel (Macronectes giganteus), St Andrew's Bay, South Georgia. Photograph taken on location for the BBC Frozen Planet series, October 2009.

Markus Varesvuo / Wilson's Storm Petrel (Oceanites oceanicus) feeding whilst 'walking on water' Atlantic ocean, Madeira Portugal, August

Hanne & Jens Eriksen / Jouanin's petrel (Bulweria fallax) in flight, Oman, September

Andy Trowbridge / Southern Giant Petrel (Macronectes giganteus) in flight off the coast of Kaikoura, Kaikoura, South Island, New Zealand. February.

Brent Stephenson / Flock of Cape petrels (Daption capense capense) in flight against the sea. Against the sun. South Shetland Islands, Antarctica, January.

Brent Stephenson / Wilson's Storm-petrel (Oceanites oceanicus) hovering whilst feeding in calm conditions. Cuverville Island, Antarctic Peninsula, Antarctica, December.

Brent Stephenson / Flock of Cape Petrels (Daption capense capense) in flight, heading away against the sky. South Shetland Islands, Antarctica, December.

Brent Stephenson / White-faced Storm-petrel (Pelagodroma marina) feeding by pattering on the sea surface. Hauraki Gulf, Auckland, New Zealand, November.

Brent Stephenson / Northern Giant Petrel (Macronectes halli) with wings outstretched and tail cocked in threat display. Off Kaikoura, Canterbury, New Zealand, October.

Chris Gomersall / 2020VISION / European storm-petrel (Hydrobates pelagicus) in flight over Irish sea off Pembrokeshire coast, Wales, UK, August 2010

Kevin Schafer / Fork-tailed storm-petrel (Oceanodroma furcata) flying low over water, Gulf of Alaska, Alaska, USA, September

Doug Allan / Snow petrel {Pagodroma nivea} flying over snowy landscape, Antarctica

Tim Laman / Cape / Pintado petrel (Daption capense) in flight over the ocean, Antarctica, January

Pete Oxford / Southern Giant Petrels (Macronectes giganteus) feeding on the carcass of a Southern Elephant seal bull, killed by Killer whales. Sea Lion Island. South of mainland east Falkland Island. Falkland Islan...

Michael Pitts / Southern giant petrel (Macronectes giganteus) head covered in blood feeding on carcass of an Elephant seal pup, with a penguin colony in the distance, St Andrews Bay, South Georgia

Roy Mangersnes / Two Cape / Pintado Petrels (Daption capense) in flight over Point Wild on Elephant Island, Southern Ocean, November.

David Tipling / Cape / Pintado petrel (Daption capense) in flight low over water, Southern Ocean off Chile, November

Hanne & Jens Eriksen / Southern Giant Petrel {Macronectes giganteus} resting on rocks, Antarctica.

Todd Pusser / New Zealand albatross {Diomedea antipodensis} and Cape petrel {Daption capense} on sea, New Zealand

Nigel Marven / Solander's petrel {Pterodroma solandri} on Lord Howe Island, Australia

LYNN M. STONE / Pintado / Cape petrels (Daption capense) in flight over ocean off South Georgia Island

Eladio Fernandez / Black-capped petrel (Pterodroma hasitata) found on the road to Valle Nuevo National Park, Dominican Republic

Eladio Fernandez / Black-capped petrel (Pterodroma hasitata) chick at nest burrow Loma del Toro, Dominican Republic

Stefan Christmann / Giant petrel (Macronectes giganteus) in flight. Atka Bay, Antarctica. January.

Stefan Christmann / Snow petrel (Pagodroma nivea) in flight. Atka Bay, Antarctica. February.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri) sleeping with Snow peterel (Pagodroma nivea) flock in background. Atka Bay, Antarctica. February.

Stefan Christmann / Snow petrel (Pagodroma nivea) in flight. Atka Bay, Antarctica. February.

Stefan Christmann / Giant petrel (Macronectes giganteus) in flight. Atka Bay, Antarctica. January.

Stefan Christmann / Giant petrel (Macronectes giganteus) in flight. Atka Bay, Antarctica. January.

Stefan Christmann / Giant petrel (Macronectes giganteus) in flight. Atka Bay, Antarctica. January.

Stefan Christmann / Snow petrel (Pagodroma nivea) in flight. Atka Bay, Antarctica. January.

Stefan Christmann / Giant petrel (Macronectes giganteus). Atka Bay, Antarctica. February.

Chris Gomersall / European storm-petrel (Hydrobates pelagicus) in flight over calm sea. Outer Hebrides, Scotland, UK, June.

David Tipling / Snow petrel (Pagadroma nivea nivea) flying around Iceberg off South Georgia, Southern Ocean January

Ashley Cooper / Southern giant petrel (Macronectes giganteus) on the beach at Gold Harbour, South Georgia, Southern Ocean. February.

Ashley Cooper / Snow petrel (Pagodroma nivea,) flying in snow, near the Antarctic Peninsula.

Tony Heald / Northern Giant Petrel (Macronectes halli) attacking to feed on King penguin (Aptenodytes patagonicus) chick. Salisbury Plain, South Georgia. September.

Tony Heald / Snow Petrel (Pagodroma nivea), four resting on floating ice. Near Twitcher Glacier, South Georgia. October 2017.

Tony Heald / Northern giant petrel (Macronectes halli) running with wings outstretched, face bloodied. St Andrews Bay, South Georgia. October.

Tony Heald / Northern giant petrel (Macronectes halli) running in aggression with bloodied face. St Andrews Bay, South Georgia. October

Tony Heald / Northern giant petrel (Macronectes halli) running with bloodied beak, King penguins (Aptenodytes patagonicus) in background. St Andrews Bay, South Georgia. September.

Tony Heald / Southern giant petrel (Macronectes giganteus) fighting with Northern giant Petrel (Macronectes halli). Southern elephant seal (Mirounga leonina) male observing in background. St Andrews Bay, South Ge...

Tony Heald / Southern giant petrel (Macronectes giganteus) and Northern giant Petrel (Macronectes halli) fighting with beaks raised upwards. Southern elephant seal (Mirounga leonina) male observing in background....

Tony Heald / Southern giant petrel (Macronectes giganteus), white colour morph. Right Whale Bay, South Georgia. September.

Tony Heald / Northern Giant Petrel (Macronectes halli) Nesting amongst Tussock Grass Ocean Harbour South Georgia Is. South Atlantic October 2017

Eric Medard / Storm petrel (Hydrobates pelagicus) in flight at night, infra-red picture, Wales, UK, July

Andy Trowbridge / Sooty shearwater (Puffinus griseus) at rest on water. Kaikoura, South Island, New Zealand. April.

Andy Trowbridge / Westland petrel (Procellaria westlandica) in flight at sea, off Kaikoura coast. Kaikoura, South Island, New Zealand. April. Vulnerable species.

Andy Trowbridge / Sooty shearwater (Puffinus griseus) resting on the water. Kaikoura, South Islnad, New Zealand. April.

Andy Trowbridge / Westland petrel (Procellaria westlandica) in flight over sea, showing the upperwing. Kaikoura, South Island, New Zealand. April. Vulnerable species.

Andy Trowbridge / Cape petrel (Daption capense) at rest on water, off Kaikoura coast. Kaikoura, South Island, New Zealand. May.

Mary McDonald / Cape petrel (Daption capense) in flight between the Falkland Islands and South Georgia, South Atlantic Ocean

Richard Robinson / Black petrels (Procellaria parkinsoni) fight over food scraps left behind by False killer whales (Pseudorca crassidens ) Northern New Zealand Editorial use only.

Richard Robinson / False killer whales (Pseudorca crassidens ) traveling with a pod of pelagic Bottlenose dolphins (Tursiops truncatus) and Black petrels (Procellaria parkinsoni ), Northern New Zealand Editorial use onl...

Nick Hawkins / Leach's storm petrel (Oceanodroma leucorhoa) in a researcher's hand with a new ring on it's leg, Machias Seal Island, Bay of Fundy, New Brunswick, Canada, July, Vulnerable species.

Nick Hawkins / Leach's storm petrel (Oceanodroma leucorhoa) forked tail displayed by a researcher, Machias Seal Island, Bay of Fundy, New Brunswick, Canada, July.

Nick Hawkins / Leach's storm petrel (Oceanodroma leucorhoa) in a researcher's hand, Machias Seal Island, Bay of Fundy, New Brunswick, Canada, July, Vulnerable species.

Nick Hawkins / Leach's storm petrel (Oceanodroma leucorhoa) chick on a researcher's hand, Machias Seal Island, Bay of Fundy, New Brunswick, Canada, July, Vulnerable species.

Andy Rouse / Southern Fulmar (Fulmarus glacialoides) flying over stormy sea Southern Ocean

Agustin Esmoris / Antarctic Giant Petrel (Macronectes giganteus) flying, Puerto Madryn, Argentina

Agustin Esmoris / Antarctic Giant Petrel (Macronectes giganteus) feeding on Southern Right Whale (Eubalaena australis) calf carcass, Puerto Madryn, Argentina

Agustin Esmoris / Antarctic Giant Petrel (Macronectes giganteus) pair feeding on Southern Right Whale (Eubalaena australis) calf carcass, Puerto Madryn, Argentina

Mike Read / Southern giant petrel (Macronectes giganteus) wings spread balancing on slippery dead Killer whale (Orcinus orca) off Sealion Island, Falkland Islands, December.

Mike Read / Southern giant petrel (Macronectes giganteus) feeding on dead Killer Whale (Orcinus orca) off Sealion Island, Falkland Islands, December.

Claudio Contreras / Southern Giant Petrel (Macronectes giganteus) in King penguin (Aptenodytes patagonicus) chick creche looking for prey. Volunteer Point, East Falkland, Falkland Islands, October

Claudio Contreras / Southern Giant Petrel (Macronectes giganteus) feeding on carcass of Southern elephant seal (Mirounga leonina) pup, Sea Lion Island, Falkland Islands, October

Claudio Contreras / Southern Giant Petrel (Macronectes giganteus), Sea Lion Island, Falkland Islands, October

Claudio Contreras / Southern Giant Petrel (Macronectes giganteus), Sea Lion Island, Falkland Islands, October

Roy Mangersnes / Elliot's storm-petrel (Oceanites gracilis) feeding on the surface near the west coast, Isabela Island, Galapagos.

Frederique Olivier / Giant petrel (Macronectes giganteus) feeding on an Adelie penguin (Pygoscelis adeliae) carcass, Adelie Land, Antarctica, January.

Frederique Olivier / Giant petrel (Macronectes giganteus) feeding on an Adelie penguin (Pygoscelis adeliae) carcass, Adelie Land, Antarctica, January.

Frederique Olivier / Giant petrel (Macronectes giganteus) feeding on an Adelie penguin (Pygoscelis adeliae) carcass, Adelie Land, Antarctica, January.

Frederique Olivier / Snow petrel (Pagodroma nivea) adjusting nest, turning around on chick, Adelie Land, Antarctica, January.

Frederique Olivier / Snow petrel (Pagodroma nivea) feeding, skimming the surface of a tide crack lake, Adelie Land, Antarctica, January.

Frederique Olivier / Snow petrel (Pagodroma nivea) feeding from the water surface of a tide crack lake, Adelie Land, Antarctica, January.

Frederique Olivier / Snow petrel (Pagodroma nivea) flying at sunset, Adelie Land, Antarctica, January.

Peter Bassett / Southern giant petrel (Macronectes giganteus) preening on a beach, with Gentoo penguins (Pygoscelis papua) and Southern elephant seals (Mirounga leonina) in the background, Gold Harbour, South Georgia...

Frederique Olivier / Southern giant petrel (Macronectes giganteus) sitting in grass, gets up and moves around, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Wide angle shot of Southern giant petrels (Macronectes giganteus), Cape petrels (Daption capense) and a Fur seal (Arctocephalus) feeding amongst kelp, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Wide angle shot of Southern giant petrels (Macronectes giganteus), Cape petrels (Daption capense) and a Fur seal (Arctocephalus) feeding amongst kelp, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Southern giant petrel (Macronectes giganteus) in a King penguin (Aptenodytes patagonicus) colony, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Southern giant petrel (Macronectes giganteus) resting along the edge of the shore, lacking alertness, potentially due to secondary poisoning from pest eradication, Macquarie Island, Sub-Antarctic Aust...

Frederique Olivier / Southern giant petrel (Macronectes giganteus) walking along the shore, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Southern giant petrel (Macronectes giganteus) resting in grass, with poisoning caused by secondary ingestion of brodifacoum, used for pest eradication, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Close-up of a Southern giant petrel (Macronectes giganteus) resting on a beach, preening, with waves breaking behind, Macquarie Island, Sub-Antarctic Australia.

Frederique Olivier / Wide shot of a group of Southern giant petrels (Macronectes giganteus) landed on water in a bay, Macquarie Island, Sub-Antarctic Australia.