Espen Bergersen / Ptarmigans (Lagopus mutus) in white winter plumage, camouflaged against mountain scree with snow, Spitsbergen, Svalbard, Norway, April

Espen Bergersen / Ptarmigans (Lagopus mutus) in white winter plumage, camouflaged against mountain scree with snow, Spitsbergen, Svalbard, Norway, April. Highly commended in the Animals in their Environment Category of...

Ingo Arndt / Rock Ptarmigan (Lagopus muta) in winter, Svalbard, Spitsbergen, Norway

Ingo Arndt / Rock Ptarmigan (Lagopus muta) in winter, Svalbard, Spitsbergen, Norway

Ole Jorgen Liodden / Svalbard ptarmigan (Lagopus muta hyperborea) female, mid-moult in autumn light. Spitsbergen, Svalbard, Norway, September.

Ole Jorgen Liodden / Svalbard ptarmigan (Lagopus mutus hyperborea) male at sunrise, Svalbard, Norway, March.

Roy Mangersnes / Svalbard ptarmigan (Lagopus muta hyperborea) in autumn as the first snow arrives on Svalbard, Norway, April.

Roy Mangersnes / Svalbard ptarmigan (Lagopus muta hyperborea) still in winter plumage in early July, outside Longyearbyen, Svalbard, Norway.

Roy Mangersnes / Svalbard Ptarmigan (Lagopus muta hyperborea) male flying, Spitsbergen, Svalbard, Norway, March.

Roy Mangersnes / Svalbard ptarmigan (Lagopus muta hyperborea) feeding, Spitsbergen, Svalbard, Norway, March.

Roy Mangersnes / Svalbard ptarmigan (Lagopus muta hyperborea) in snow with winter plumage, Spitsbergen, Svalbard, Norway, March.

Mary McDonald / Rock ptarmigan (Lagopus muta) pair mating with female in summer plumage and male in winter plumage, Longyearbyen, Spitsbergen, Svalbard, Norway. June.