Ingo Arndt / Convergent Lady Beetle (Hippodamia convergens) mass overwintering hidden in tree bark, California

Alex Hyde / Orange 16-Spot Ladybird (Halyzia 16-guttata / sedecimguttata) overwintering in recess of carved letter on a gravestone. Peak District National Park, Derbyshire, UK, March 2012.

Nick Upton / Single male of an overwintering species of Greenbottle (Eudasyphora cyanella) sunbasking in early spring sunshine on Forsythia flower. Wiltshire garden, UK, March.

Jeff Wilson / The crew of United States Coastguard Cutter 'Healy' prepare decks in the Bering sea, Alaska, USA. The ship served as a platform for the Frozen Planet crew whilst filming Spectacled eider ducks overwin...

Nick Upton / Male Greenbottle fly (Eudasyphora cyanella) sunbasking on a leaf. This is an overwintering species. Wiltshire, UK, March

Nick Upton / Two male Greenbottle flies (Eudasyphora cyanella) competing with one another as they search for mates. This is an overwintering species. Wiltshire, UK, March

Ingo Arndt / Brambling (Fringilla montifringilla) flock, four million, returning to sleeping place during overwintering in Black Forest, Germany

Ingo Arndt / Schreibers' Long-fingered Bat (Miniopterus schreibersii) colony overwintering, Sardinia, Italy

Ingo Arndt / Schreibers' Long-fingered Bat (Miniopterus schreibersii) group overwintering, Sardinia, Italy

Ingo Arndt / Schreibers' Long-fingered Bat (Miniopterus schreibersii) group overwintering, Sardinia, Italy

Ingo Arndt / Snow Goose (Chen caerulescens) flock before sunrise overwintering at Bosque del Apache National Wildlife Refuge, New Mexico

Ingo Arndt / Monarch (Danaus plexippus) butterfly group flying, during a warm day when the overwintering period draws to an end large numbers become active, Michoacan, Mexico