Tony Heald / Glaucous Gull (Larus hyperboreus) taking off from ice, Svalbard Norway, July.

Alan Murphy / Glaucous Gull (Larus hyperboreus) striking at a fish while in flight, British Columbia, Canada

Roy Mangersnes / Glaucious gull (Larus hyperboreus) flying against a blue glacier front, Spitsbergen, Svalbard, Norway, September

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) on blue ice. Spitsbergen, Svalbard, July.

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) with blooded face looking at Glaucous Gull (Larus hyperboreus) in flight. Spitsbergen, Svalbard, July.

Wild Wonders of Europe / de la Lez / Glaucous gull (Larus hyperboreus) in flight, Moselbukta, Svalbard, Norway, July 2008

Wild Wonders of Europe / de la Lez / Glaucous gull (Larus hyperboreus) in flight, Moselbukta, Svalbard, Norway, July 2008

Wild Wonders of Europe / Liodden / Two Glaucous gulls (Larus hyperboreus) flying past a glacier, Spitsbergen, Svalbard, March 2009

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} adult, Monaco Glacier, Svalbard, Norway

Robin Chittenden / Glaucous gull (Larus hyperboreus) Norfolk, England, UK, February.

Robin Chittenden / Glaucous gull (Larus hyperboreus) Norfolk, England, UK. February.

SCOTLAND: The Big Picture / Glaucous gull, (Larus hyperboreus), 2nd winter, chasing hooded crow from carcass, Scotland, UK.February

David Tipling / Glaucous gull (Larus hyperboreus) adult winter Sheringham Norfolk, England, UK. January

David Tipling / Glaucous gull (Larus hyperboreus) 1st winter plumage Sheringham Norfolk, England, UK. January

Jeff Vanuga / Common eider duck (Somateria mollissima) female defending nest against Glaucous gull (Larus hyperboreus) in Spitsbergen, Svalbard, Norway. June.

Manuel Schulz/ BIA / Glaucous Gull (Larus hyperboreus) flying with stolen egg prey, Iceland

Pal Hermansen / Glaucous gull (Larus hyperboreus) eating on Brunnich's guillemot (Uria lomvia) chick, Alkrefjellet bird cliff Hinlopen, Svalbard, Norway, July.

Pal Hermansen / Glaucous gull (Larus hyperboreus) in front of ship, Svalbard, Norway, July.

Pal Hermansen / Glaucous gull (Larus hyperboreus) eating dead Brunnich's guillemot (Uria lomvia) Alkefjellet, Hinlopenstrait, Svalbard, Norway, July.

Pal Hermansen / Glaucous gull (Larus hyperboreus) eating dead Kittiwake (Rissa tridactyla) Alkefjellet, Svalbard, Norway, July 2016.

Markus Varesvuo / Glaucous gull (Larus hyperboreus) in flight over sea, Vardo, Norway March

Gerrit Vyn / Glaucous Gull (Larus hyperboreus) alert from behind grass, Yukon Delta National Wildlife Refuge, Alaska, USA June

Jussi Murtosaari / Glaucous gull (Larus hyperboreus), juvenile in flight, Hornoya, Norway, April.

Sven Zacek / Polar bear (Ursus maritimus) with Glaucous gull (Larus hyperboreus) in snowfall, Svalbard, Spitsbergen, Norway, June.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) perched on ice, Hornsund, Svalbard, Norway, June.

Ole Jorgen Liodden / Polar bear (Ursus maritimus) and Glaucous gull (Larus hyperboreus) in Svalbard, Norway, July 2014.

Ole Jorgen Liodden / Glaucous gull (Larus hyperboreus hyperboreus) in flight over sea, Spitsbergen, Svalbard, Norway, July 2007.

Ole Jorgen Liodden / Glaucous gull (Larus hyperboreus) feeding on chick on water, Spitsbergen, Svalbard, August.

Alan Murphy / Glaucous Gull (Larus hyperboreus) flying, Alaska

Alan Murphy / Glaucous Gull (Larus hyperboreus), British Columbia, Canada

Alan Murphy / Glaucous Gull (Larus hyperboreus) flying, British Columbia, Canada

Ole Jorgen Liodden / Glaucous gull (Larus hyperboreus) perched on ice, Hornsund, Svalbard, Norway, June.

Ole Jorgen Liodden / Polar bear (Ursus maritimus) attacking glaucous gull (Larus hyperboreus) in water, Svalbard, Norway, August. Sequence 1/3

Ole Jorgen Liodden / Polar bear (Ursus maritimus) attacking glaucous gull (Larus hyperboreus) in water, Svalbard, Norway, August. Sequence 2/3

Ole Jorgen Liodden / Polar bear (Ursus maritimus) attacking glaucous gull (Larus hyperboreus) in water, Svalbard, Norway, August. Sequence 3/3

Winfried Wisniewski / Glaucous Gull (Larus hyperboreus) pair on cliff, Iceland

Ben Cranke / Glaucous gull (Larus hyperboreus) roosting on iceberg, Svalbard, Norway. July.

Ben Cranke / Glaucous gull (Larus hyperboreus) Svalbard, Norway. July.

Markus Varesvuo / Glaucous gull (Larus hyperboreus) flying in snow fall, Norway, Europe, April.

Markus Varesvuo / Glaucous Gull (Larus hyperboreus) flying over water, Norway, April

Markus Varesvuo / Glaucous Gull (Larus hyperboreus) in flight, Norway, April

Bryan and Cherry Alexander / Glaucous gulls (Larus hyperboreus) squabbling whilst waiting for a Polar bear (Ursus maritimus) to leave its kill so they can scavenge, Svalbard, Norway.

Pal Hermansen / Polar bear (Ursus maritimus) with seal prey, with Glaucous gull (Larus hyperboreus) and Ivory gull (Pagophila eburnea), Franz Josef Land, arctic Russia.

Sergey Gorshkov / Polar bear (Ursus maritimus) group on beach, one with carcass, also Glaucous gulls (Larus hyperboreus) Wrangel Island, Far Eastern Russia, September.

Christophe Courteau / Glaucous gull (Larus hyperboreus), Spitzbergen, Svalbard, Norway, June.

Matthew Studebaker / Glaucous Gull (Larus hyperboreus), Alaska

Sergey Gorshkov / Glaucous Gull (Larus hyperboreus) flock on iceberg, Wrangel Island, Russia

Cyril Ruoso / Glaucous Gull (Larus hyperboreus) flying, West Fjords, Iceland

Staffan Widstrand / Glaucous gull (Larus hyperboreus) profile portrait, Svalbard, Norway July

Staffan Widstrand / Glaucous gull (Larus hyperboreus) stretching wings, Svalbard, Norway

Markus Varesvuo / Glaucous gull (Larus hyperboreus) subadult in flight, Norway, April

Markus Varesvuo / Glaucous gull (Larus hyperboreus) profile, Norway, April

Markus Varesvuo / Glaucous gull (Larus hyperboreus) in flight over water, Iceland, June

Markus Varesvuo / Glaucous gull (Larus hyperboreus) portrait, Norway, April

Roy Mangersnes / Polar bear (Ursus maritimus) playing with an injured Glaucous gull (Larus hyperboreus) Spitsbergen, Svalbard, Norway, August

Roy Mangersnes / Four Glaucous gulls (Larus hyperboreus) Spitsbergen, Svalbard, Norway, August

Roy Mangersnes / Polar bear (Ursus maritimus) playing with an injured Glaucous gull (Larus hyperboreus) Spitsbergen, Svalbard, Norway, August

Roy Mangersnes / Polar bear (Ursus maritimus) playing with an injured Glaucous gull (Larus hyperboreus) Spitsbergen, Svalbard, Norway, August

Robin Chittenden / Glaucous gull (Larus hyperboreus) in flight, Sheringham, Norfolk, UK, February

Robin Chittenden / Glaucous gulls (Larus hyperboreus) Sheringham Norfolk, UK, February

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) at seal kill, with two Glaucous Gulls (Larus hyperboreus) fighting over scraps. Nordaustlandet, Svalbard, September.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) taking flight from ice. Spitsbergen, Svalbard, July.

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) at seal kill, with Glaucous gull (Larus hyperboreus) in foreground. Nordaustlandet, Svalbard, September.

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) attacking Glaucous Gull (Larus hyperboreus) on water. Spitsbergen, Svalbard, August.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) resting on ice. Spitsbergen, Svalbard, July.

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) attacking Glaucous Gull (Larus hyperboreus) on water. Spitsbergen, Svalbard, August.

Ole Jorgen Liodden / Polar Bear (Ursus maritimus) attacking and catching Glaucous Gull (Larus hyperboreus) on water. Spitsbergen, Svalbard, August.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) trying to swallow a guillemot (Uria aalge) chick. Spitsbergen, Svalbard, August.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) in flight, backlit. Spitsbergen, Svalbard, July.

Ole Jorgen Liodden / Glaucous Gull (Larus hyperboreus) on blue ice. Spitsbergen, Svalbard, August.

Ole Jorgen Liodden / Two Polar Bears (Ursus maritimus) attacking Glaucous Gull (Larus hyperboreus) on water. Spitsbergen, Svalbard, August.

Markus Varesvuo / Glaucous Gull (Larus hyperboreus) in flight in front of a nearly full moon. Norway, April.

Brent Stephenson / Juvenile Glaucous Gull (Larus hyperboreus) standing on the shoreline. Sermet Glacier, Prince Christian Sound, Southern Greenland, August.

Markus Varesvuo / Glaucous Gull (Larus hyperboreus) adult in winter plumage, Norway, March

Roger Powell / Immature Glaucous Gull (Pluvialis apricaria) fighting an immature Greater Black-backed Gull (Larus marinus), Varanger Fjord, Arctic Norway. June

Roger Powell / Immature Glaucous Gull (Larus hyperboreus) fighting an immature Great Black-backed Gull (Larus marinus) Varanger Fjord, Arctic Norway. June

Roger Powell / Immature Glaucous Gull (Larus hyperboreus) standing on shoreline, Varanger Fjord, Arctic Norway. June

Suzi Eszterhas / Glaucous-winged Gull eggs (Larus glaucescens) nest amongst driftwood debris, Katmai National Park, Alaska, USA, June 2008

Suzi Eszterhas / Glaucous-winged Gull (Larus glaucescens) chick sheltering against log, Katmai National Park, Alaska, USA, June

Kevin Schafer / Glaucous Gull (Larus hyperboreus) group in front of Monaco Glacier, Leifdefjorden, Svalbard, Norway

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} two sitting in grass, Iceland, June

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} flock on stony beach, Iceland, June

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} standing on a bed of kelp surrounded by water, Iceland, June

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} in flight, Iceland, June

Wild Wonders of Europe / de la Lez / Glaucous gull (Larus hyperboreus) in flight, Moselbukta, Svalbard, Norway, July 2008

Matthias Breiter / Glaucous Gull (Larus hyperboreus) landing, Kenora, Canada

Matthias Breiter / Glaucous Gull (Larus hyperboreus) landing, Tracy Arm Fjord, Alaska

Roy Mangersnes / Glaucous gull (Larus hyperboreus) in flight off Point Barrow, National Petroleum Reserves, Arctic Alaska, USA. June

Roger Powell / Immature (2nd winter plumage) Glaucous Gull {Larus hyperboreus} feeding on shoreline, Varanger shore, Norway

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} in flight, Ilulissat, Greenland

Hanne & Jens Eriksen / Glaucous gull {Larus hyperboreus} 2nd summer plumage, North Coast, Svalbard, Norway

Konrad Wothe / Glaucous Gull (Larus hyperboreus) on ice floe, Spitsbergen, Norway

Chris Gomersall / Glaucous gull (Larus hyperboreus) perching on fence post. Iceland. July 2006

Staffan Widstrand / Glaucous gull (Larus hyperboreus) in flight, Baffin Island, Canada

Staffan Widstrand / Glaucous gull flying {Larus huperboreus} Baffin Island, Canada

Staffan Widstrand / Glaucous gull flying {Larus hyperboreus} Svalbard, Norway