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)

An Egyptian security guard screams at people as medics bring in a stretcher to carry the wounded after the attack which killed President Anwar Sadat, October 6, 1981, as he watched a military parade. (Photo by AP Photo)

A Brussels Airlines aircraft prepares for landing in Cointrin airport during sunrise over the Mont Blanc in Geneva December 1, 2011. (Photo by Denis Balibouse/Reuters)

The Heavens opened as students from Wells Blue school year 13 pupils arrived at The Bishop's Palace in Wells, Somerset on June 30, 2022 for their end of year school prom. (Photo by Jason Bryant/Apex News)

A man falls from a horse at a rodeo exhibition during Tradition Day, aimed to preserve gaucho traditions, in San Antonio de Areco, Argentina, Sunday, November 13, 2022. Tradition Day is celebrated to honor the birth of Argentine writer Jose Hernandez, author of the country's national poem “The Gaucho Martin Fierro”. (Photo by Natacha Pisarenko/AP Photo)

The northern lights as seen from from Yell in the Shetland Islands, Scotland on January 15, 2023. The aurora borealis is caused by collisions between electrically charged particles released from the sun that enter the Earth’s atmosphere and collide with gases such as oxygen and nitrogen. (Photo by Ryan Nisbet/Capture Media Agency)

A rainbow rises over flooded fields after the Rivers Thames and Churn burst their banks, in Cricklade, western England on January 3, 2024, following Storm Henk which brought strong winds and heavy rain across much of the country. (Photo by Adrian Dennis/AFP Photo)

Model Adriana Lima attends Madonna presents An Evening of Music, Art, Mischief and Performance to benefit Raising Malawi at Faena Forum on December 2, 2016 in Miami Beach, Florida. (Photo by Jeff Kravitz/FilmMagic for Raising Malawi)