Wim van den Heever / Whooper swan (Cygnus cygnus) mid flight over the frozen lake, Kussharo, Hokkaido, Japan.

Wim van den Heever / Whooper swan (Cygnus cygnus) portrait, on frozen lake Kussharo, Hokkaido Japan, February.

Wim van den Heever / Whooper swans (Cygnus cygnus) juvenile with adults behind, on frozen Lake Kussharo, Hokkaido, Japan. February.

Danny Green / Whooper swans (Cygnus cygnus) two in flight, during snowfall, Lake Kussharo, Japan, February

Danny Green / Whooper swan (Cygnus cygnus) in flight in snowfall, Lake Kussharo, Japan, February

Konrad Wothe / Whooper Swan (Cygnus cygnus) pair arguing at wintering site, Kussharo-ko, Hokkaido, Japan

Wim van den Heever / Whooper swans (Cygnus cygnus) flock in early evening in a snow storm, Lake Kussharo, Hokkaido Japan. Taken with remote camera,

Wim van den Heever / Whooper swans (Cygnus cygnus) early evening in a snow storm, Lake Kussharo, Hokkaido, Japan. Taken with remote camera.

Wim van den Heever / Whooper swans (Cygnus cygnus) at night in snow blizzard, Lake Kussharo, Hokkaido Japan.

Wim van den Heever / Whooper swans (Cygnus cygnus) swimming in formation on Lake Kussharo, Hokkaido Japan.

Wim van den Heever / Whooper swans (Cygnus cygnus) sitting on frozen Lake Kussharo in a huge snow storm, Hokkaido Japan.

Wim van den Heever / Whooper swans (Cygnus cygnus) flock on Lake Kussharo. Hokkaido Japan. Taken at eye level using remote camera setup.