Dietmar Nill / Great grey shrike with impaled frog prey, Germany

Charlie Summers / American Pika (Ochotona princeps) leaping from one alpine rock to another as it heads to its home carrying food for the winter months. Rocky Mountain National Park, Colorado, USA. August.

David Tipling / Grey squirrel (Sciurus carolinensis) collecting sweet chestnuts (Castanea sativa) to cache for winter. Richmond Park, London, England, UK. October.

David Tipling / Grey squirrel (Sciurus carolinensis) collecting sweet chestnuts (Castanea sativa) to cache for winter, Richmond Park, London, England, UK. October.

David Tipling / Grey squirrel (Sciurus carolinensis) collecting sweet chestnuts (Castanea sativa) to cache for winter, Richmond Park, London, England, UK. October.

SCOTLAND: The Big Picture / Red squirrel (Sciurus vulgaris) with Acorn in mouth, at edge of Pine forest. Ling (Calluna vulgaris) in background. Glenfeshie, Cairngorms National Park, Scotland, UK.

Remi Masson / European beaver (Castor fiber) swimming underwater, above branches and foliage stored for eating later. River Rhone, Rhone-Alpes, France, June.

Remi Masson / European beaver (Castor fiber) swimming underwater, above branches and foliage stored for eating later. River Rhone, Rhone-Alpes, France, June.

Ashley Cooper / Sun Island in Almere, which is the Netherlands youngest town, in Flevoland, which was reclaimed from the sea. This planned city is very green, with space heating provided from a nearby combined heat a...

Jeff Foott / Pika (Ochotona princeps) gathering plants to store for winter, Bridger National Forest, Wyoming, USA. August.

Pal Hermansen / Spotted nutcracker (Nucifraga caryocatactes) finding cached hazelnut, Sweden, February.

Philippe Clement / European pine marten (Martes martes) hiding a dead bird in a food cache, Bavarian Forest National Park, Germany, May. Captive.