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 woman poses for a picture next to a caterpillar-tracked Bentley Continental GT, which was modified by Russian car engineering enthusiasts, during a demonstration in St. Petersburg, Russia on June 7, 2019. (Photo by Anton Vaganov/Reuters)

Members of a dance troupe participate in the Cabildo de Getsemani parade as part of the 208th Independence celebrations in Carta​gena, Colombia, 10 November 2019. (Photo by Ricardo Maldonado Rozo/EPA/EFE)

A cow is silhouetted grazing next the smoke of a chimney of an incineration plant in Lausanne at sunrise on November 19, 2021. (Photo by Fabrice Coffrini/AFP Photo)

British actor Hugh Grant and his girlfriend Elizabeth Hurley attend the post-premiere party of Grant's latest film, “Four Weddings and a Funeral” in London, 11th May 1994. (Photo by Dave Hogan/Hulton Archive/Getty Images)

Sea lions make dinner plans in the Gulf of California early July 2024. The gulf is a primary source of sardines and anchovies, two of Mexico’s top marine resources. (Photo by Glenn Ostle/Solent News)

A model poses with her arm after it was painted by body artist Guido Daniele into the likeness of a snake at Harrods on Februrary 4, 2008 in London, England. Guido Daniele has painted human hands since 2000. Each work of art takes over three hours to complete. (Photo by Chris Jackson/Getty Images)

Professional dog walker Jon Lovette of Jonny Walkers walks with dogs at Crissy Field on October 19, 2011 in San Francisco, California.