Espen Bergersen / Common guillemot (Uria aalge) calling, bridled guillemot morph with white ring around the eye, Hornoya bird cliff, Finnmark, Norway. March.

Hanne & Jens Eriksen / Black guillemot (Cepphus grylle) taking off, Denmark, May

Wild Wonders of Europe / Liodden / Black guillemot (Cepphus grylle) in flight over water, Spitsbergen, Svalbard, March 2009

Wild Wonders of Europe / Liodden / Black guillemot (Cepphus grylle) diving into water, Spitsbergen, Svalbard, March 2009

Markus Varesvuo / Guillemot (Uria aalge) in flight over water, Norway, July

Roger Powell / Black Guillemot {Cepphus grylle} with Sandeel fish in beak trying to entice a female to his nest site, Caithness, Scotland, UK

Andrew Parkinson / Black guillemot (Cepphus grylle) with a fish in its beak, evening light, Shetland Islands, Scotland, UK, July

SCOTLAND: The Big Picture / Back guillemots (Cepphus grylle) interacting on a rock, Shetland, Scotland, UK, April.

SCOTLAND: The Big Picture / Black guillmots (Cepphus grylle) interacting and chasing one another, Shetland, Scotland, UK, April.

SCOTLAND: The Big Picture / Black guillmot (Cepphus grylle) chasing another black guillemot with fish, Shetland, Scotland, UK, August.

Markus Varesvuo / Black guillemot (Cepphus grylle) with fish in beak, portrait. Shetland, Scotland, UK. July.

Markus Varesvuo / Black guillemot (Cepphus grylle) with beak wide open. Shetland, Scotland, UK. July.

Philippe Clement / Pair of Black guillemots (Cepphus grylle) resting on a sea cliff, Shetland Islands, Scotland, UK, June.

Philippe Clement / Pair of Black guillemots (Cepphus grylle) resting on a sea cliff, Shetland Islands, Scotland, UK, June.

Philippe Clement / Black guillemot / tystie (Cepphus grylle) resting on rock ledge in sea cliff, Shetland Islands, Scotland, UK, June

Robert Thompson / Guillemot (Uria aalge), parent and chick in breeding colony. Great Saltee Island, Saltee Islands, County Wexford, Republic of Ireland. June.

Klein & Hubert / Black guillemot (Cepphus grylle) with fish, Svalbard, Norway.

Espen Bergersen / Common guillemot (Uria aalge), Brunnich's guillemot (Uria lomvia) and Kittiwake (Rissa tridactyla) in flight near, Hornoya birdcliff, Vardo, Norway. March

Ashley Cooper / Guillemot (Uria aalge) covered in oil on a black sand volcanic beach at Vik, on Iceland. September 2010.

Ashley Cooper / Guillemot (Uria aalge) covered in oil on a black sand volcanic beach at Vik, on Iceland. September 2010.

Werner Bollmann / Guillemots (Uria aalge) flock in flight, Hornoya, Norway.

Werner Bollmann / Guillemots (Uria aalge) group in mist, Hornoya, Norway.

Werner Bollmann / Guillemots (Uria aalge) colony, Hornoya, Norway. March 2013.

Sandra Bartocha / Common guillemot (Uria aalge) and Black-legged kittiwake (Rissa tridactyla) Hornoya, Norway, March.

Espen Bergersen / Dead bird possibly Black guillemot (Cepphus grylle) caught in discarded fishing net, Rebbenesoya, Troms, Norway, April.

Espen Bergersen / Dead bird possibly Black guillemot (Cepphus grylle) caught in discarded fishing net, Rebbenesoya, Troms, Norway, April.

Philippe Clement / Kittiwakes (Rissa tridactyla), Common guillemots (Uria aalge) and Razorbills (Alca torda) nesting on rock ledges in breeding colony, Fowlsheugh RSPB Reserve, Aberdeenshire, Scotland, UK, May

Jussi Murtosaari / Black guillemots (Cepphus grylle) two flying over sea, Finland, April.

Guy Edwardes / Black guillemot (Cepphus grylle) feeding, Foula, Shetland Islands, Scotland, August.

Guy Edwardes / Black guillemot (Cepphus grylle) feeding, Foula, Shetland Islands, Scotland, August.

Guy Edwardes / Black guillemot (Cepphus grylle) vocalising, Foula, Shetland Islands, Scotland, August., August.

Guy Edwardes / Black guillemot (Cepphus grylle) feeding, Foula, Shetland Islands, Scotland, August.

Guy Edwardes / Two Black guillemots (Cepphus grylle) interacting, calling, Foula Shetland Islands, Scotland

Guy Edwardes / Two Black guillemots (Cepphus grylle) interacting, calling, Foula Shetland Islands, Scotland

Guy Edwardes / Black guillemot (Cepphus grylle) feeding, Foula, Shetland Islands, Scotland, August.

Guy Edwardes / Black guillemot (Cepphus grylle) feeding, Foula, Shetland Islands, Scotland, August.

Guy Edwardes / Three Black guillemots (Cepphus grylle) interacting, calling, Foula, Shetland Islands, Scotland, August.

Markus Varesvuo / Guillemots (Uria aalge) taking off in snow, Norway, March.

Markus Varesvuo / Black Guillemot (Cepphus grylle) resting on rock, stretching wings, Shetland, UK, July.

Eric Baccega / Flock of Black guillemots (Cepphus grylle) swimming, Arctic Bay, Nunavut, Canada, June.

Terry Whittaker / Black guillemot (Cepphus grylle) two sitting on rock vocalising, Flatey Island, Breioafjorour, Iceland, July

Terry Whittaker / Black guillemot (Cepphus grylle) two sitting on rock vocalising, Flatey Island, Breioafjorour, Iceland, July

Terry Whittaker / Black guillemot (Cepphus grylle) sitting on rock, Flatey Island, Breioafjorour, Iceland, July

Terry Whittaker / Black guillemot (Cepphus grylle) sitting on rock, Flatey Island, Breioafjorour, Iceland, July

Cyril Ruoso / Black guillemots (Cepphus grylle) on porch of traditional house, Skjaervaer Island, Vega archipelago, Norway June

Cyril Ruoso / Black Guillemot (Cepphus grylle) mating Skjaervaer Island Vega Archipelago NORWAY Guillemot à miroir (Cepphus...

Cyril Ruoso / Black Guillemot (Cepphus grylle) Courtship Skjaervaer Island Vega Archipelago NORWAY Guillemot à miroir (Cepphu...

Cyril Ruoso / Black Guillemot (Cepphus grylle) Skjaervaer Island Vega Archipelago NORWAY Guillemot à miroir (...