The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

Russian Prime Minister and presidential candidate Vladimir Putin speaks during a rally after Putin claimed victory in the presidential election at the Manezhnya Square March, 4, 2012 in Moscow, Russia. Exit polls showed Putin had over 60 percent of the vote according to state television in an election that has been alleged to be marred by widespread violations. (Photo by Oleg Nikishin/Epsilon/Getty Images)

“People and Space”. Winner: Wanderer in Patagonia by Yuri Zvezdny (Russia) A lone stargazer stares up at the stars of our galaxy, the Milky Way, as they stretch across the night sky over the glacier “White Stones” (Piedras Blancas) in the Los Glaciares National Park, Argentina. El Chaltén, Santa Cruz Province, Argentina, 27 September 2016 iOptron Sky-Tracker mount, Sony A7S camera, 18 mm f/2.8 lens, ISO 5000, 30-second exposure Wanderer in Patagonia. (Photo by Yuri Zvezdny/Insight Astronomy Photographer of the Year 2017)

British underwater photographer of the year – winner. “Love Birds” by Grant Thomas (UK). Location: Luss Pier, Loch Lomond, Scotland. Thomas’s initial idea was to frame a split shot of one swan feeding below the surface of the water but when he noticed how comfortable they were around him he was confident, with some patience, he could get that magical shot of the two. (Photo by Grant Thomas/UPY 2018)

“Red Arrows” at the 2016 royal air tattoo, RAF Fairford, UK. By Jonny Williams, finalist: action. (Photo by Jonny Williams/UK National Geographic Traveller Photography Competition 2018)

Run by the Society of German Nature Photographers (Gesellschaft Deutscher Tierfotografen), the prestigious annual contest celebrates the best wildlife photography from members in Germany. Here: Landscapes, second place: Florian Smit, “Rainforest” (Danum valley, Borneo). (Photo by Florian Smit/2019 GDT Nature Photographer of the Year)

Coast and marine winner: Storm Gull (Lesser black-backed gull), New Haven, East Sussex. (Photo by Craig Denford/British Wildlife Photography Awards)

International photographic competition, which runs in association with the Royal Botanic Gardens in Kew, London, awards special prize for the best close-up images. Here: Winner – Mayflies by Petar Sabol, Goričan, Croatia. (Photo by Sabol Petar/International Garden Photographer of the Year)