Peter Cairns / Isle of Rum at sunset viewed from Eigg, Scotland, April 2013.

Peter Cairns / Isle of Rum at sunset viewed from Eigg, Scotland, April 2013.

Ernie Janes / Boat full of people watching Common Seals (Phoca vitulina) on sand bank at Blakeney Point, Norfolk, August 2013.

Guy Edwardes / Quilota Crater Lake, Cotopaxi Province, Ecuador, September 2010.

Enrique Lopez-Tapia / Domestic Asian elephants (Elephas maximas) used for riding safaris with their keepers, Royal Chitwan National Park, Nepal.

Enrique Lopez-Tapia / Domestic Asian elephants (Elephas maximas) used for riding safaris with their keepers, Royal Chitwan National Park, Nepal.

Enrique Lopez-Tapia / Tourists riding domesticated Indian Elephant (Elephas maximas) on safari, Royal Chitwan National Park, Nepal. October 2011.

Christophe Courteau / Tourists and guide using snowshoes on an ecotourism trekking holiday, Svalbard, Norway, June, 2012. Model released.

Kirkendall-Spring / Lower Yellowstone Falls on the Yellowstone River viewed from Artist Point, Yellowstone National Park, Wyoming, USA, June 2013.

Kirkendall-Spring / Camp site at night above Appleton Pass in Olympic National Park, Washington, USA, August 2013.

Enrique Lopez-Tapia,Enrique Lopez-Tapia / Gentoo penguin (Pygoscelis papua) and Antarctic cruise liner 'MV Ushuaia' in Neko Harbour, Andvord Bay. Antarctic Peninsula, Antarctica

Willem Kolvoort / View of Byoutier. a very small island in the Seychelles with a pristine beach. Byoutier, Seychelles March 2005