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)

A Turkey-backed Syrian fighter fires a rocket-propelled grenade as he takes part in a military exercise in the countryside of the northwestern city of Afrin, in rebel-held part of Aleppo province, on May 31, 2022. (Photo by Rami al Sayed/AFP Photo)

A person watches Mount Etna, Europe's most active volcano, light up the night sky with eruptions, as seen from Piazzale Funivia dell'Etna, Italy on December 1, 2023. (Photo by Etna Walk/Giuseppe Distefano/Handout via Reuters)

Tourists visit teamLab Planets Tokyo in Tokyo on January 10, 2025. Japan on January 15 will announce tourist figures for the year 2024, widely expected to break the record set in 2019. (Photo by Kazuhiro Nogi/AFP Photo)

Papier-mache sculptures, also known as “ninots”, burn during the “Nit de la Crema” (Fire Night) of the Fallas Festival in Valencia, eastern Spain, 19 March 2024. Fallas is a fortnight-long fiesta in which installations of parodic papier-mache, cardboard, and wooden sculptures are traditionally burnt every year on the last day of the event in the so-called “Crema” to end the festivities. (Photo by Biel Alino/EPA/EFE)

The sun rises this morning behind the 173ft spire of St Mary's church in the market town of Whittlesey in Cambridgeshire, UK on February 17, 2024. The church dates from the 13th century with the Ashlar faced tower added in the 15th century. (Photo by Andrew McCaren/London News Pictures)

A member of the Grupa Magnifica acrobatics club poses for a photo on the Baltic Sea beach during sunset in the town of Leba, Pomeranian region, on August 6, 2024. (Photo by Sergei Gapon/AFP Photo)

A hot air balloon competition called “Grudziadzkie Zawody Balonowe” is held in Lisie Katy, central-northern Poland, 14 May 2021. The compe​tition is held for the eighteenth time. (Photo by Tytus Zmijewski/EPA/EFE)