Erlend Haarberg / European shag (Phalacrocorax aristotelis) sitting at the entrance of a cave with flock of Common guillemots (Uria aalge) and Gulls (Laridae) flying past cave, Hornoya and Reinoya Nature Reserve, Finnm...

Espen Bergersen / European shags (Phalacrocorax aristotelis) in courtship display. Hornoya bird cliff, Finnmark, Norway. March.

Espen Bergersen / Atlantic puffin (Fratercula arctica) and European shag (Phalacrocorax aristotelis) Hornoya, Finnmark, Norway. March.

David Pattyn / Shag (Phalacrocorax aristotelis) flying with nesting material, Hornoya, Varanger, Finnmark, Norway, May.

David Pattyn / Shag (Phalacrocorax aristotelis) spreading wings to dry, Hornoya, Varanger, Finnmark, Norway, April.

Roy Mangersnes / Rock shag (Phalacrocorax magellanicus) coming in to the nest with nesting material. Gypsy Cove, Falkland Islands.

Andy Trowbridge / European / Common shag (Phalacrocorax aristotelis) portrait with open beak, close-up. Vardo, Norway. July.

Ann & Steve Toon / National Trust ranger Laura Shearer monitoring nesting seabirds, Inner Farne, Farne Islands, Northumberland, UK, July.

Ann & Steve Toon / Measuring shag chick (Phalacrocorax aristotelis) for research, Inner Farne, Farne Islands, Northumberland, UK, July.

Robert Thompson / Shag (Phalacrocorax aristotelis) in profile, Northern Ireland, UK. May.

Hanne & Jens Eriksen / Socotra cormorant (Phalacrocorax nigrogularis) roosting on cliffs, Oman, December

Roger Powell / Shag (Phalacrocorax aristotelis) in winter plumage landing on a tidal creek. Cresswell, Druridge Bay, Northumberland, UK, March.

Roger Powell / Shag (Phalacrocorax aristotelis) in winter plumage flying, Cresswell, Druridge Bay, Northumberland, UK, March.

Jiri Lochman / Little pied cormorant (Phalacrocorax melanoleucos), Cape Range National Park, Ningaloo Coast UNESCO Natural World Heritage Site, Western Australia, Australia.

Sylvain Cordier / White bellied shag (Leucocarbo atriceps albiventer), nesting colony on Pebble island, Falkland islands

Sylvain Cordier / King Shag or White bellied shag (Leucocarbo atriceps albiventer) in flight over nesting colony on Pebble island, Falkland islands

Sylvain Cordier / White bellied shag (Leucocarbo atriceps albiventer) in flight over nesting colony on Pebble island, Falkland islands

Sylvain Cordier / White bellied shag (Leucocarbo atriceps albiventer), returning from the sea with nesting material, Pebble island, Falkland islands

Sylvain Cordier / Striated caracara (Phalcoboenus australis), adult predating a young White bellied shag (Leucocarbo atriceps albiventer), Stepple Jason Island, Falkland islands

Sylvain Cordier / White bellied shag (Leucocarbo atriceps albiventer), chick begging food from its parent, in nesting colony on Pebble island, Falkland islands

Sylvain Cordier / Falkland skua (Catharacta antarctica) adult with predated King cormorant / White bellied shag (Leucocarbo atriceps albiventer) egg, on Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica), adult predating an egg in a colony of White bellied shag (Leucocarbo atriceps albiventer) on Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica) flying with predated King cormorant / White bellied shag (Leucocarbo atriceps albiventer) egg in its beak, on Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica) adult with predated King cormorant / White bellied shag (Leucocarbo atriceps albiventer) egg, Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica) adult with predated King cormorant / White bellied shag (Leucocarbo atriceps albiventer) chick, Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica) adult with predated King cormorant / White bellied shag (Leucocarbo atriceps albiventer) egg, Pebble Island, Falkland Islands

Sylvain Cordier / Falkland Skua (Catharacta antarctica), two fighting over White bellied shag (Leucocarbo atriceps albiventer) chick,Pebble Island , Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica), adult predating White bellied shag (Leucocarbo atriceps albiventer) egg on Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica) adult taking a King cormorant / White bellied shag (Leucocarbo atriceps albiventer) chick from nesting colony, Pebble Island, Falkland Islands

Sylvain Cordier / Falkland skua (Catharacta antarctica), adult predating a young King cormorant / White bellied shag (Leucocarbo atriceps albiventer) chick, Pebble Island , Falkland Islands

Markus Varesvuo / Shag (Phalacrocorax aristotelis) pair, necks entwined in bonding behaviour, Vardö, Norway.

Niall Benvie / Shag (Phalacrocorax aristotelis) in silhouette, Lunga, Scotland, UK, May.

Christophe Courteau / Cape cormorant (Phalacrocorax capensis) at rest, Skeleton Coast, Namibia. October

Christophe Courteau / Cape cormorant (Phalacrocorax capensis) at rest, Skeleton Coast, Namibia. October

Christophe Courteau / Cape cormorant (Phalacrocorax capensis) at rest, Skeleton Coast, Namibia. October

Markus Varesvuo / Shag (Phalacrocorax aristotelis) in flight, Vardo, Norway March

Markus Varesvuo / Shag (Phalacrocorax aristotelis) building nest on coastal cliff, Vardo, Norway March

Markus Varesvuo / Shag (Phalacrocorax aristotelis) two heads showing above rock, Vardo, Norway March

Mark Carwardine / South Georgian shag (Phalacrocorax georgianus - formerly Phalacrocorax atriceps georgianus) flying, Stromnes, South Georgia, November

Mark Carwardine / South Georgian shag (Phalacrocorax georgianus - formerly Phalacrocorax atriceps georgianus) nesting on abandoned whaliing station, Stromnes, South Georgia, November

Mark Carwardine / South Georgian shag (Phalacrocorax georgianus - formerly Phalacrocorax atriceps georgianus) flying with nesting material in beak, Stromnes, South Georgia, November

Mark Carwardine / South Georgian shag (Phalacrocorax georgianus - formerly Phalacrocorax atriceps georgianus) flying with nesting material in beak, Stromnes, South Georgia, November

Mark Carwardine / South Georgian shag (Phalacrocorax georgianus - formerly Phalacrocorax atriceps georgianus) nesting on abandoned whaliing station, one just landed with nesting material, Stromnes, South Georgia, Novem...

Mark Carwardine / South Georgian shag (Phalacrocorax georgianus - formerly Phalacrocorax atriceps georgianus) on sea surface, Grytviken, South Georgia, November

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) juvenile at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) juvenile at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) juvenile at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Richard Robinson / Auckland Island shag (Leucocarbo colensoi) juvenile at Enderby Island in the subantarctic Auckland Islands archipelago, New Zealand, January Editorial use only.

Roger Powell / Little pied cormorant (Phalacrocorax melanoleucos) sitting on marine post and preening. Werribee Sewerage Farm, Werribee, Victoria, Australia

Loic Poidevin / Landscape of Vardo Nature Reserve with European shag (Phalacrocorax aristotelis) Vardo, Varenger, Norway, April.

Loic Poidevin / European shag (Phalacrocorax aristotelis) group resting on the coast, Hornoya Island, Norway, May.

Loic Poidevin / European shag (Phalacrocorax aristotelis) group of four resting on the coast, Hornoya Island, Norway, May.

Loic Poidevin / European shag (Phalacrocorax aristotelis) group resting on the coast, Hornoya Island, Norway, May.

Loic Poidevin / European shag (Phalacrocorax aristotelis) on nest with egg, Hornoya, Norway, May.

Loic Poidevin / European shag (Phalacrocorax aristotelis) pair mating, Hornoya, Norway, May.

Loic Poidevin / European shag (Phalacrocorax aristotelis) pair in courtship at the nest, Hornoya, Norway, May.

Loic Poidevin / European shag (Phalacrocorax aristotelis) portrait, Hornoya, Norway, May.

Hanne & Jens Eriksen / Socotra cormorant (Phalacrocorax nigrogularis) taking off from the sea, Oman, August

Chris & Monique Fallows / Cape cormorant (Phalacrocorax capensis), feeding on sardine baitball, False Bay, Cape Town, South Africa, July.

Graham Eaton / Shag (Phalacrocorax aristotelis) on a sea cliff. Cardigan Bay, Wales. March.

Graham Eaton / Shag (Phalacrocorax aristotelis) standing on sea cliff. Cardigan Bay, Wales. March.

Pal Hermansen / Shags (Phalacrocorax aristotelis) in snow at coast, Hornya, Finnmark, Norway March

Pal Hermansen / Shags (Phalacrocorax aristotelis) standing in coastal snow blizzard, Hornya, Finnmark, Norway March

Pal Hermansen / Shags (Phalacrocorax aristotelis) in snow at coast, Hornya, Finnmark, Norway March

Ann & Steve Toon / Cape cormorants (Phalacrocorax capensis) on nesting platform, Lambert's Bay, Western Cape, South Africa

Pal Hermansen / Group of European shags (Phalacrocorax aristotelis) in snow, on the coast of Finnmark, Norway, March.

Pal Hermansen / Group of European shags (Phalacrocorax aristotelis) in snow, on the coast of Finnmark, Norway, March.

Andres M. Dominguez / European shag (Phalacrocorax aristotelis) feeding chick at nest,Farne Islands, Northumberland, UK, June.

Jussi Murtosaari / Common shag (Phalacrocorax aristotelis) carrying nest building materials, Norway, April.

Orsolya Haarberg / Common guillemots (Uria aalge) flying past the entrance to a cave, with Shags (Phalacrocorax aristotelis) perched in the foreground, Hornoya Island, Finnmark, Norway, March.

Erlend Haarberg / Shags (Phalacrocorax aristotelis) resting on coastal rocks, Hornoya and Reinoya Nature Reserve, Finnmark, Norway, March.

Erlend Haarberg / European shag (Phalacrocorax aristotelis) portrait, in breeding plumage, Hornoya and Reinoya Nature Reserve, Finnmark, Norway, March.

Brent Stephenson / Imperial shag (Phalacrocorax atriceps bransfieldensis) portrait, swimming at sea, Port Lockroy, Antarctic Peninsula, Antarctica, January.

Brent Stephenson / Chatham shag (Phalacrocorax onslowi) portrai, Matarakau, Main Chatham, Chatham Islands, New Zealand, April. Critically endangered species.

Brent Stephenson / Imperial shag (Phalacrocorax atriceps atriceps) pair courting at their nest site, Saunders Island, Falkland Islands, South Atlantic, December.

Brent Stephenson / Imperial shag (Phalacrocorax atriceps atriceps) pair courting at their nest site, male presenting nesting material, Saunders Island, Falkland Islands, South Atlantic, December.

Brent Stephenson / Imperial shag (Phalacrocorax atriceps atriceps) pair courting at their nest site, Saunders Island, Falkland Islands, South Atlantic, December.

Brent Stephenson / Imperial shag (Phalacrocorax atriceps atriceps) landing, Saunders Island, Falkland Islands, South Atlantic, December.

Brent Stephenson / Rock shag (Phalacrocorax magellanicus) portrait, Carcass Island, Falkland Islands, South Atlantic, December.

Brent Stephenson / Little pied cormorant (Phalacrocorax melanoleucos) drying with wings outstretched, perching on branch, Hawkes Bay, New Zealand, November.

Brent Stephenson / Little pied cormorant (Phalacrocorax melanoleucos) shaking water from its plumage, sitting on a branch close to the surface of the water, Tamatea, Hawkes Bay, New Zealand, November.

Brent Stephenson / Little pied cormorant (Phalacrocorax melanoleucos) on a branch close to the surface of the water, Tamatea, Hawkes Bay, New Zealand, November.

Staffan Widstrand / European shag (Phalacrocorax aristotelis) Hornoya Island, Varanger Peninsula, Norway, March.

Staffan Widstrand / European shag (Phalacrocorax aristotelis) Hornoya Island, Varanger Peninsula, Norway, March.

Marie Read / Red-faced cormorant (Phalacrocorax urile) on nest on cliff ledge, brooding large nestling, St. Paul Island, Pribilofs, Alaska, USA

Cyril Ruoso / Ornithologist Francis Daunt catching European shag (Phalacrocorax aristotelis) to retrieve GPS tag, near Flatey Island, West fjord, Iceland, June.

Cyril Ruoso / European shag (Phalacrocorax aristotelis) sitting on nest, West fjord, Iceland, June.

Espen Bergersen / European shags (Phalacrocorax aristotelis) in courtship display. Hornoya bird cliff, Finnmark, Norway. March.

Espen Bergersen / European shag (Phalacrocorax aristotelis) close up portrait, in breeding plumage. Hornya bird cliff, Finnmark, Norway.

Espen Bergersen / European shags (Phalacrocorax aristotelis) in courtship display. Hornoya bird cliff, Finnmark, Norway. March.

Espen Bergersen / European shags (Phalacrocorax aristotelis) in courtship display. Hornoya bird cliff, Finnmark, Norway. March.