A Tibetan rider fires his weapon as he perfoms his riding skills at the Qinghai Yushu Horse Racing Festival on July 27, 2007 in Yushu County of Yushu Tibetan Autonomous Prefecture, Qinghai Province, northwest China. The Horse Racing Festival of Tibetan nomads in Yushu Prefecture falls in late July and early August on the Tibetan calendar. During the festival, various equestrian skills will be performed along with singing, dancing and costume shows. (Photo by China Photos/Getty Images)

About a dozen dogs traded in their leashes for life vests Saturday for the chance to ride the waves at Jupiter beach as part of a canine surfing competition to raise money for an animal rescue group. Photo: Musso paddles in with Jengo. (Photo by Taylor Jones/The Palm Beach Post)

Body surfers ride a large wave at the Wedge in Newport Beach of the Southland coast on May 20, 2011 in Newport, California. Surfers have been lured to the south facing beaches for the biggest swells of the season. (Photo by Kevork Djansezian/Getty Images)

A woman rides a mechanical bull before participating in the 4th annual Running of The Bulls October 15, 2011 in Cave Creek, Arizona. (Photo by Joshua Lott/Getty Images)

An idol of Hindu goddess Durga floats in water as devotees immerse the same in the River Kuakhai after the Durga Puja festival in Bhubaneswar, India, Saturday, October 24, 2015. The immersion of idols marks the end of the festival that commemorates the slaying of a demon king by lion-riding, 10-armed goddess Durga, marking the triumph of good over evil. (Photo by Biswaranjan Rout/AP Photo)

Bolivia's president Evo Morales holds his scared staffs of power during a blessing by Aymaran spiritual guides, in a traditional ceremony at the archeological site Tiwanaku, Bolivia, Wednesday, January 21, 2015. Morales is set to begin a new term Thursday, that will make him the Andean nation's longest-serving leader, riding high on a wave of unprecedented growth and stability. (Photo by Juan Karita/AP Photo)

A woman waits at a polio immunisation health centre, in Maiduguri, Borno State, Nigeria, August 29, 2016. Nigeria's military has liberated large swathes of land from Boko Haram but a ride with an army convoy, all guns firing for fear of ambush, shows how far the northeast is from normality after a brutal Islamist insurgency that has displaced millions. (Photo by Afolabi Sotunde/Reuters)

Inmates ride in a bus out of the Cojutepeque prison in El Salvador, Thursday, June 16, 2016. This prison, which houses more than a thousand 18th street imprisoned gang members, will be closed down by the government, since it has been unable to prevent the amount of illegal activities happening inside the prison walls. Inmates will be relocated to other medium-security prisons. (Photo by Salvador Melendez/AP Photo)