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)

Children play on top of an old plane's fuselage at a dump site in Paranaque city, Metro Manila, Philippines January 21, 2017. (Photo by Ezra Acayan/Reuters)

A PETA (People for the Ethical Treatment of Animals) activist with her body painted promotes veganism in Bangkok April 21, 2016. (Photo by Jorge Silva/Reuters)

This picture released by Turkish Cumhuriyet Daily newspaper shows Dilek Dundar (L), the wife of editor-in-chief of Turkish newspaper Cumhuriyet daily Can Dundar, trying to stop a gunman who is also being held back by a man on May 6, 2016 in Istanbul. Turkish opposition journalist Can Dundar escaped a shooting on May 5 outside a courthouse in Istanbul where he is on trial, adding police detained the assailant. Dundar, who was unharmed, was outside the courthouse during a break as the court prepared to deliver its verdict in his trial for allegedly revealing state secrets in a newspaper story. (Photo by AFP Photo/Cumhuriyet Daily Newspaper)

Commuters by with the buildings of the banking district in background in Frankfurt, Germany, Thursday, February 6, 2020. (Photo by Michael Probst/AP Photo)

A sanitation worker fumigates using sodium hypochlorite in an archive room to fight the spread of the coronavirus disease (COVID-19) in the Milimani commercial courts in Nairobi, Kenya, July 17, 2020. (Photo by Baz Ratner/Reuters)

A fan of England cheers prior to the UEFA EURO 2020 quarter final match between Ukraine and England in Rome, Italy, 03 July 2021. (Photo by Mike Hewitt /EPA/EFE)

People are silhouetted while riding the Atmosfear double swing, which lifts riders more than 66 meters into the air while spinning at up to 70 km/h, at the Pacific National Exhibition at sunset in Vancouver, British Columbia, on Tuesday, August 31, 2021. (Photo by Darryl Dyck/The Canadian Press via AP Photo)