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)

Soldiers stand guard in Maua square where a cotton candy vendor passes by in Rio de Janeiro, Brazil, Saturday, July 9, 2016, as security is deployed to get to know the areas they'll be patrolling during the Olympics. Roughly twice the security contingent at the London Olympics will be deployed during the August games in Rio, which are expected to draw thousands of foreigners to a city where armed muggings, stray bullets and turf wars between heavily armed drug gangs are routine. (Photo by Leo Correa/AP Photo)

In this Monday, January 23, 2017 photo, chicken feet snacks shop owner Leung Kin-kung testes a chicken feet in Hong Kong. Saturday marks the start of the lunar Year of the Rooster and families in China will reunite for festivities, fireworks and food. While tradition calls for feasting on “auspicious” foods, many will also munch on staple snacks like “phoenix claws”, the Chinese name for chicken feet. (Photo by Vincent Yu/AP 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 young man “painting” the Eiffel Tower. (Photo by Keystone/Getty Images). 9th May 1970

A drag queen waves a rainbow flag during an LGBT rights demonstration in front of the Hungarian Parliament building in Budapest, Hungary on June 14, 2021. During the protest human rights activists called on lawmakers in Hungary to reject legislation banning any content portraying or promoting homosexuality or sеx reassignment to anyone under 18. The bills, aiming at fighting pedophilia, have various amendments which would outlaw any depiction or discussion of different gender identities to youth in the public sphere. (Photo by Bela Szandelszky/AP Photo)

A Ukrainian dancer of the Kyiv City Ballet company stretches prior to a performance at the Theatre de Chatelet, in Paris, Tuesday, March 8, 2022. The Kyiv City Ballet danced to a full house in Paris for the last show of a French tour that has left the company stranded after the war broke out in Ukraine. They described being physically and emotionally exhausted. Being given the opportunity to train and dance was for many a chance to focus on something other than the war. (Photo by Thibault Camus/AP Photo)

A crowd of people gathered at the seaside of Udaipur, Digha, India before a cloud burst of rain on May 21, 2022. India Meteorological Department (IMD) has predicted that the Monsoon rain will likely arrive a week early this year due to twin cyclones, Asani and Karim. (Photo by Avishek Das/SOPA Images/LightRocket via Getty Images)