Ole Jorgen Liodden / Arctic fox (Alopex lagopus lagopus) grooming in summer fur, Spitsberg, Svalbard, Norway, August.

Ole Jorgen Liodden / Arctic fox (Alopex lagopus lagopus) mid moult into summer fur, back lit portrait, Spitsbergen, Svalbard, Norway, June.

Pete Oxford / Waved Albatross (Phoebastria irrorata) molting juvenile, Espanola Island, Galapagos Islands, Ecuador

Pete Oxford / Waved Albatross (Phoebastria irrorata) molting juvenile, Espanola Island, Galapagos Islands, Ecuador

Pete Oxford / Waved Albatross (Phoebastria irrorata) molting juvenile, Espanola Island, Galapagos Islands, Ecuador

Stefan Christmann / Emperor Penguin (Aptenodytes forsteri) molting chick, Queen Maud Land, Antarctica

Pascal Kobeh / Aggregation of thousands of Spider crabs (Leptomithrax gaimardii) for moulting, South Australia Basin, Australia. Pacific Ocean.

Pascal Kobeh / Aggregation of thousands of Spider crabs (Leptomithrax gaimardii) for moulting, South Australia Basin, Australia. Pacific Ocean.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) with Snow goose egg in mouth, mid moult from winter to summer fur, Wrangel Island, Far Eastern Russia.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) with Snow goose egg in mouth, mid moult from winter to summer fur, Wrangel Island, Far Eastern Russia, June.

Sergey Gorshkov / Arctic fox (Vulpes lagopus) with Snow goose egg in mouth, mid moult from winter to summer fur, Wrangel Island, Far Eastern Russia, June.

Andy Trowbridge / Arctic Fox (Alopex / Vulpes lagopus) running low to the ground, during moult from grey summer fur to winter white. Dovrefjell National Park, Norway, September.