A dog rides a wave during the Surf City Surf Dog competition in Huntington Beach, California, U.S., September 25, 2016. The dogs compete in contest categories ranging from small to extra large, to two dogs on a board, as well as owner and dog. (Photo by Lucy Nicholson/Reuters)

A Belarussian tourist crosses the river as he takes part in “Search and rescue operations – 2016”, a three-day competition, near the village of Priselki, Belarus, November 25, 2016. Photo taken November 25, 2016. (Photo by Vasily Fedosenko/Reuters)

A worker refreshes himself with a fan after loading a container with rice bags at an export plant in the central Chainat province in Thailand, December 16, 2015. (Photo by Jorge Silva/Reuters)

Models wait backstage during the Ukrainian Fashion Week in Kiev, October 16, 2015. (Photo by Valentyn Ogirenko/Reuters)

A knight parades in the street during the traditional carnival parade in Cologne, western Germany, Monday, February 16, 2015. (Photo by Martin Meissner/AP Photo)

An angler fishes on the opening day of the salmon fishing season on the River Tay at Kenmore in Scotland, Britain January 16, 2017. (Photo by Russell Cheyne/Reuters)

A murmuration of migrating starlings is seen across the sky near the village of Beit Kama in southern Israel on January 16, 2018. (Photo by Amir Cohen/Reuters)

A soldier walks on the bank of the river in central Pyongyang, North Korea on April 16, 2017. (Photo by Damir Sagolj/Reuters)