Ole Jorgen Liodden / Pacific Gull (Larus pacificus) Tasmania. December.

Ernie Janes / Pacific gulls (Larus pacificus) in flight over beach Tasmania, Australia.

Ernie Janes / Pacific gull (Larus pacificus) feeding on beach, Tasmania, Australia.

Ernie Janes / Pacific gull (Larus pacificus) feeding on beach, Tasmania, Australia.

Gerrit Vyn / Slaty-backed gull (Larus schistisagus) calling. Chukotka, Russia. June.

Gerrit Vyn / Slaty-backed gull (Larus schistisagus) Chukotka, Russia. June.

Jan Wegener / Pacific Gull (Larus pacificus), Australia

Jan Wegener / Pacific Gull (Larus pacificus), Melbourne, Australia

Ole Jorgen Liodden / Pacific Gull (Larus pacificus) in flight. Tasmania. December.

Martin Willis / Pacific Gull (Larus pacificus) pair by the ocean, Cheyne Beach, Western Australia, Australia

Jouan & Rius / Pacific gull (Larus pacificus) portrait of juvenile standing on rocks, Kalbarri National Park, Western Australia

Jouan & Rius / Pacific gull (Larus pacificus), Kangaroo Island, South Australia, Australia

Dave Watts / Pacific Gull (Larus pacificus) stetching it's wings, Tasmania, Australia

Dave Watts / Pacific gull in flight {Larus pacificus} Australia

Gary Bell/ Oceanwide / Pacific Gull (Larus pacificus) stretching, South Australia, Australia

Rob Drummond/ BIA / Pacific Gull (Larus pacificus) juvenile feeding on fish prey, Victoria, Australia, sequence 4 of 4

Rob Drummond/ BIA / Pacific Gull (Larus pacificus) juvenile feeding on fish prey, Victoria, Australia, sequence 3 of 4

Rob Drummond/ BIA / Pacific Gull (Larus pacificus) juvenile feeding on fish prey, Victoria, Australia, sequence 2 of 4

Rob Drummond/ BIA / Pacific Gull (Larus pacificus) juvenile feeding on fish prey, Victoria, Australia, sequence 1 of 4

Jan Wegener/ BIA / Pacific Gull (Larus pacificus) pair, Melbourne, Australia

Doug Gimesy / Pacific gull (Larus pacificus) on water, Sandringham, Victoria, Australia.

Doug Gimesy / Pacific gull (Larus pacificus) portrait, Port Philip Bay, Sandringham, Victoria, Australia.

Doug Gimesy / Pacific gull (Larus pacificus) walking through shallow water, foraging in intertidal rocks, Port Philip Bay, Sandringham, Victoria, Australia.

Doug Gimesy / Pacific gull (Larus pacificus) feeding on a mussel on intertidal rocks, Port Philip Bay, Sandringham, Victoria, Australia.

Doug Gimesy / Pacific Gull (Larus pacificus), juvenile, in flight, Victoria, Australia.

Doug Gimesy / Pacific Gull (Larus pacificus), juvenile, in flight, Victoria, Australia.

Doug Gimesy / Pacific gull (Larus pacificus) holding sea urchin (Echinoidea) in its beak on edge of shore line, Victoria, Australia.

Doug Gimesy / Pacific Gull (Larus pacificus), juvenile, on edge of shore line, Victoria, Australia.

Tony Wu / Male Red-breasted merganser (Mergus serrator) holding just caught Righteye flounder (Pleuronectidae), fleeing from Slaty-backed gull (Larus schistisagus). Hokkaido, Japan. February.

Tony Wu / Slaty-backed gull (Larus schistisagus) eating Righteye flounder (Pleuronectidae) stolen from Common merganser (Mergus merganser). The bird's nictitating membrane closed to protect its eyes while...

Tony Wu / Slaty-backed gull (Larus schistisagus) eating Righteye flounder (Pleuronectidae) stolen from Common merganser (Mergus merganser). The bird's nictitating membrane closed to protect its eyes while...

Doug Gimesy / Young Pacific gull (Larus pacificus) holding and feeding on fish whilst in flight low over ground. Victoria, Australia.

Doug Gimesy / Juvenile Pacific gull (Larus pacificus) on the intertidal zone rocks with two Silver gulls (Chroicocephalus novaehollandiae) in background, Sandringham, Victoria, Australia.

Doug Gimesy / Juvenile Pacific gull (Larus pacificus) feeding on fish on the intertidal zone rocks, Sandringham, Victoria, Australia.

Doug Gimesy / Juvenile Pacific gull (Larus pacificus) flying with fish in beak, Sandringham, Victoria, Australia.

Doug Gimesy / Juvenile Pacific gull (Larus pacificus) eating fish on the intertidal zone rocks, Sandringham, Victoria, Australia.

Doug Gimesy / Juvenile Pacific gull (Larus pacificus) flying with fish in beak, Sandringham, Victoria, Australia.

Guy Edwardes / Slaty-backed gull (Larus schistisagus) in flight, Hokkaido,Japan. February

Doug Gimesy / Pacific gull (Larus pacificus) in flight on a cloudy day. Sandringham, Victoria, Australia.

Doug Gimesy / Pacific gull (Larus pacificus) in flight on a cloudy day. Sandringham, Victoria, Australia.

Jenny E. Ross / Slaty-backed gulls (Larus schistisagus) and Black-legged kittiwakes (Rissa tridactyla) on the shore of Verkhoturova Island, Koryaksky Nature Reserve, Bering Sea, Kamchtaka, Russia.