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)

A couple take photographs alongside the National Monument on Calton Hill, Edinburgh on Wednesday January 5, 2022, ahead of First Minister Nicola Sturgeon's update to the Scottish Parliament on the Covid-19 situation as the Omicron variant sweeps across the country. (Photo by Jane Barlow/PA Images via Getty Images)

Participants at the Dubai Run at Sheikh Zayed Road in Dubai, United Arab Emirates on November 26, 2021. (Photo by Ruel Pableo for The National)

People explore the ice covered pier in Port Stanley, Ontario, Canada, on December 27, 2022. The ice formations were created by a large winter storm which hit the region on over the Christmas weekend. Temperatures were expected to moderate across the eastern and midwest US on December 27, after days of freezing weather from "the blizzard of the century" left at least 49 dead and caused Christmas travel chaos. (Photo by Geoff Robins/AFP Photo)

A person watches Mount Etna, Europe's most active volcano, light up the night sky with eruptions, as seen from Piazzale Funivia dell'Etna, Italy on December 1, 2023. (Photo by Etna Walk/Giuseppe Distefano/Handout via Reuters)

The sun rises over the north sea as The Couple by artist Sean Henery sits just of the coast at Newbiggin-by-the-Sea, England, Wednesday October 8, 2014. (Photo by Owen Humphreys/AP Photo/PA Wire)

The moon rises behind Reunion Tower in downtown Dallas, Sunday evening, November 13, 2016. On Monday the supermoon will be the closest full moon to earth since 1948, and it won't be as close again until 2034. (Photo by Tom Fox/The Dallas Morning News via AP Photo)

Long Exposure pictures showing Mount Sinabung spewing out hot lava on August 2, 2017 in Karo, Indonesia. Sinabung located in North Sumatra Province roared back to life in 2010 for the first time in 400 years. After another period of inactivity it erupted once more in 2013, and has remained highly active since. (Photo by Albert Damanik/Barcroft Images)