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

Doug Gimesy / Northern giant petrel (Macronectes halli) squawking, portrait, another in background. Buckles Bay, Macquarie Island, Sub-Antarctic Australia. December.

Doug Gimesy / Northern giant petrel (Macronectes halli) portrait, another in background. Buckles Bay, Macquarie Island, Sub-Antarctic Australia. December.

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

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

Rick Price / Northern giant petrels (Macronectes halli) feeding on a seal carcass, surrounded by Southern elephant seals (Mirounga leonina), Gild Harbour, South Georgia, Antarctica. October.

Rick Price / Two Northern giant petrels (Macronectes halli) on the water, one with a bloodied face from feeding on an elephant seal carcass, Gold Harbour, South Georgia, Antarctica. October.

Rick Price / Northern giant petrels (Macronectes halli) feeding on an elephant seal bull carcass, Peggoty Bluff, South Georgia, Antarctica. October.

Rick Price / Northern giant petrels (Macronectes halli) fighting over an elephant seal bull carcass, Peggoty Bluff, South Georgia, Antarctica. October.

Mark Carwardine / Northern giant petrel (Macronectes halli) threatening another individual over dead seal carcass, Gold Harbour, South Georgia, November

Mark Carwardine / Northern giant petrel (Macronectes halli) fighting over dead seal carcass, Gold Harbour, South Georgia, November

Mark Carwardine / Northern giant petrel (Macronectes halli) rear view of bird displaying over dead seal carcass, Gold Harbour, South Georgia, November

Mark Carwardine / Northern giant petrel (Macronectes halli) displaying over dead seal carcass, Gold Harbour, South Georgia, November

Mark Carwardine / Northern giant petrel (Macronectes halli) fighting over dead seal carcass, Gold Harbour, South Georgia, November

Richard Robinson / A Northern giant petrel (Macronectes halli) feasts on a dead New Zealand sea lion (Phocarctos hookeri) at the Sandy Bay colony, Enderby Island, Auckland Islands archipelago, New Zealand. January 2016....

Richard Robinson / A Northern giant petrel (Macronectes halli) feasts on a dead New Zealand sea lion (Phocarctos hookeri) at the Sandy Bay colony, Enderby Island, Auckland Islands archipelago, New Zealand. January 2016....

Richard Robinson / Great white shark (Carcharodon carcharias) and two Northern giant petrel (Macronectes halli) feeding on a recently deceased Humpback whale (Megaptera novaeangliae) calf, around six metres long off the...

Richard Robinson / Great white shark (Carcharodon carcharias) and two Northern giant petrel (Macronectes halli) feeding on a recently deceased Humpback whale (Megaptera novaeangliae) calf, around six metres long off the...

Richard Robinson / Antipodean albatross (Diomedea antipodensis) and Northern giant petrel (Macronectes halli) feeding on a recently deceased Humpback whale (Megaptera novaeangliae) calf around six metres long with disti...

Richard Robinson / Northern giant petrel (Macronectes halli) juvenile on ground, Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Northern giant petrel (Macronectes halli) juvenile on ground, Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Northern giant petrel (Macronectes halli) juvenile calling on ground, Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Northern giant petrel (Macronectes halli) in flight, Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Northern giant petrel (Macronectes halli) feeds on dead New Zealand sealion pup (Phocarctos hookeri) Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use...

Richard Robinson / Northern giant petrel (Macronectes halli) feeds on dead New Zealand sealion pup (Phocarctos hookeri) Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use...

Richard Robinson / Northern giant petrel (Macronectes halli) feeds on dead New Zealand sealion pup (Phocarctos hookeri) Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use...

Richard Robinson / Northern giant petrel (Macronectes halli) chick sits upon a bed of Acaena minor (var. antarctica) a prostrate dicotyledonous herb at Enderby Island in the subantarctic Auckland Islands archipelago, Ne...

David Tipling / RF - Northern Giant Petrel (Macronectes halli) near Kaikoura, New Zealand. November. (This image may be licensed either as rights managed or royalty free.)

Chris & Monique Fallows / White capped albatross (Thalassarche steadi) fighting with Northern giant petrel (Macronectes halli), Kaikoura, New Zealand, March.

Chris & Monique Fallows / Wandering albatross (Diomedea exulans) and Northern giant petrel (Macronectes halli) squabbling, Kaikoura, New Zealand, March.

Brent Stephenson / Northern giant petrel (Macronectes halli) flying over sea, during moult in the outer wing, with several inner primaries/outer secondaries missing, South Atlantic, January.

Brent Stephenson / Northern Giant petrel (Macronectes halli) flying low over the sea, showing moult in the outer wing, with several inner primaries/outer secondaries missin, South Atlantic, January.

Brent Stephenson / Northern Giant petrel (Macronectes halli) in flight, South Atlantic, January.

Brent Stephenson / Northern giant petrel (Macronectes halli) in flight showing the underside of its wings, South Atlantic, January.

Brent Stephenson / Northern giant petrel (Macronectes halli) with wings stretched on water, off Kaikoura, Canterbury, New Zealand, November.

Brent Stephenson / Northern giant petrel (Macronectes halli) taking off from water. Off Kaikoura, Canterbury, New Zealand, November.

Theo Webb / Northern giant petrel (Macronectes halli) feeding on the carcass of a dead female Antarctic fur seal (Arctocephalus gazella) South Georgia Island.

Theo Webb / Northern giant petrel (Macronectes halli) South Georgia Island.

Chris & Monique Fallows / Northern Giant Petrel (Macronectes halli) in flight, Southern Ocean.

Konrad Wothe / Northern Giant Petrel swimming (Macronectes halli) South Georgia, Antarctic. February.

Konrad Wothe / Northern Giant Petrel (Macronectes halli) in flight South Georgia, Antarctica. February.

Brent Stephenson / Northern giant petrel (Macronectes halli) flying at sea with land in the background, Kaikoura, Canterbury, New Zealand, October.