Sylvain Cordier / Monarch butterfly (Danaus plexippus) wintering in Oyamel pine forests (Abies religiosa) Monarch Butterfly Biosphere Reserve / Reserva de Biosfera de la Mariposa Monarca UNESCO World Heritage Site, An...

Sylvain Cordier / Monarch butterfly (Danaus plexippus), wintering from November to March in Oyamel pine forests (Abies religiosa) Monarch Butterfly Biosphere Reserve, Mexico.

Ingo Arndt / Bark beetle (Scolytinae) galleries in dead spruce tree (Picea abies), Bayerischer Wald / Bavarian Forest National Park, Germany., June.

Jack Dykinga / Douglas firs (Pseudotsuga menziesii) in 'Wall Street' Canyon. Bryce Canyon National Park, Utah, USA, October.

David Pattyn / Alpine ibex (Capra ibex) on a mountain side in autumn with European larch tree (Larix decidua) trees in the back the Alps, Gran Paradiso National Park, Italy. November.

Orsolya Haarberg / Snow covered Norway spruce (Picea abies) trees at the treeline, Stubba Nature Reserve, Laponia, Sweden, February 2013.

Orsolya Haarberg / Snow covered Norway spruce (Picea abies) forest on Mount Harghita Madaras, Carpathian Mountains, Transylvania, Romania, January 2015.

Orsolya Haarberg / Norway spruce (Picea abies) trees covered in snow, Ciuc Mountains, Transylvania, Romania, January 2015.

Erlend Haarberg / Norway spruce trees (Picea abies) covered in snow and frost, at sunrise, Mellan-Stubba, Stubba Nature Reserve, Lapland, Sweden, February 2013.

Wild Wonders of Europe / Möllers / Mixed Common beech (Fagus sylvatica) and Spruce (Picea abies) forests in autumn colours at sunrise seen from the road to Muntele Mic. Southern Carpathians, Muntii Tarcu, Caras-Severin, Romania, Octobe...

Konstantin Mikhailov / Lake Ann surrounded by Douglas firs (Pseudotsuga menziesii) Silver firs (Abies alba) and other conifers in the area of Rainy Pass of North Cascades National Park, North Cascades National Park, Cascade...

Erlend Haarberg / Norway spruce (Picea abies) forest covered by packed snow, Riisitunturi National Park, Finland, February 2006