Global wildlife populations will decline by 67% by 2020 unless urgent action is taken to reduce human impact on species and ecosystems, warns the biennial Living Planet Index report from WWF (World Wide Fund for Nature) and ZSL (Zoological Society of London). From elephants to eels, here are some of the wildlife populations most affected by human activity. Here: The maned wolf is among the large mammals in the Brazilian Cerrado that are threatened by the increasing conversion of grasslands into farmland for grazing and growing crops. (Photo by Ben Cranke/Nature Picture Library/Alamy Stock Photo)

People clash with Venezuelan National Guards as they try to cross the border to Colombia over the Francisco de Paula Santander international bridge in Urena, Venezuela December 18, 2016. (Photo by Carlos Eduardo Ramirez/Reuters)

Jason Ramsay and Amy Laverty, from Arbroth, Scotland, pose beside a large Christmas tree at Bondi Beach on December 25, 2016 in Sydney, Australia. Bondi Beach is a popular tourist destination on Christmas Day. (Photo by Don Arnold/Getty Images)

A competitor reacts as she emerges from the water during the Tough Guy event in Perton, central England, January 26, 2014. The annual Tough Guy race – “the toughest race in the world” – at Perton in Staffordshire. Tough Guy claims to be the world’s most demanding one-day survival ordeal. First staged in 1987, the Tough Guy Challenge has been widely described as one of the hardest races of it’s type with up to one-third of the starters failing to finish in a typical year. (Photo by Darren Staples/Reuters)

It’s a classic tale of dictatorship gone wrong and the fight for freedom. Like in any good battle, there’s fire, albeit from firecrackers, but the ammunition in this one is – flour. It takes place in a Hemingway-esque Spanish village. The battle of “Enfarinats” in celebration of the Els Enfarinats festival, rages on on December 28, 2012 in Ibi, Spain. Citizens of Ibi annually celebrate the festival with a fight using flour, eggs and firecrackers. The battle takes place between two groups, a group of married men called “Els Enfarinats” who take the control of the village for one day pronouncing a number of ridiculous laws and fining the citizens that infringe them and a group called “La Oposicio” who try to restore order. At the end of the day the money collected from the fines is donated to charitable causes in the village. The festival has been celebrated since 1981 after the town of Ibi recovered the tradition but the origins remain unknown.

Photo: A Reveller smokes during the battle of “Enfarinats”, a flour fight in celebration of the Els Enfarinats festival. (Photo by David Ramos)

A young man “painting” the Eiffel Tower. (Photo by Keystone/Getty Images). 9th May 1970

A French soldier stands near a military combat command vehicle on display at The Defence and Security Exhibition on September 13, 2011 in London, England. ExCeL London is hosting the exhibition with hundreds of manufacturers from all over the world displaying their hardware. (Photo by Peter Macdiarmid/Getty Images)

A lighting bolt flashes in the sky as U.S. Army M1A1 Abram tanks roll through the desert December 9, 2002 near the Iraqi border in Kuwait. (Photo by Joe Raedle/Getty Images)