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)

Brazilian model and television personality Alessandra Ambrosio attends Alessandra Ambrosio And Darren Dzienciol's Horror In The Hills on October 31, 2019 in Beverly Hills, California. (Photo by Rochelle Brodin/Getty Images)

Zookeeper Agata holds a rare newborn Brazilian three-banded armadillo inside its enclosure at the Wroclaw Zoo in Wroclaw, Poland on May 11, 2023. The Tolypeutes matatus, or the southern armor also known as bolita or tatu-bola, is a fairly popular animal in South America but is increasingly rare. The new zoo child was born on March 23. The species is listed as vulnerable by the International Union for the Conservation of Nature (IUCN) and threatened by habitat loss and hunting. (Photo by Omar Marques/Anadolu Agency via Getty Images)

A child plays in front of “Etnias”, a large graffiti wall by Brazilian graffiti artist Eduardo Kobra created ahead of the Rio 2016 Olympic Games at Porto Maravilha in Rio de Janeiro, Brazil, 30 July 2016. The Olympics start on 05 August. Eduardo Kobra hopes to set a Guinness World Record for the largest graffiti created by a single artist. (Photo by Lukas Coch/EPA)

A resident types a text message on her mobile phone, as she sits on a bench made from a tree, which is a creation by Brazilian artist Hugo Franca at Largo da Batata square in Sao Paulo March 17, 2015. Franca, a designer from Sao Paulo is working with the city to make use of fallen trees to turn them into sculpture furniture to line the city's parks, streets and plazas. Brazil's largest city was slammed by several strong storms this rainy season that brought with them heavy rain, lightning and winds as high as 90 kilometres (55 miles) per hour. (Photo by Nacho Doce/Reuters)

Police fire rubber bullets as they help an Atletico Paranaense fan during clashes between Vasco da Gama soccer fans and Atletico Paranaense fans at their Brazilian championship match in Joinville in Santa Catarina, on December 8, 2013. Dozens of fans fought a savage battle on the terraces at the match on Sunday, interrupting play for more than one hour and leaving at least three people reportedly in serious condition. (Photo by Carlos Moraes/Agência O DIA)

Prints of R$ 50 Brazilian reais bills sit on a table for inspection at at the Casa da Moeda, the national mint, in the Santa Cruz suburb of Rio de Janeiro, Brazil, on Tuesday, March 5, 2013. Brazil is likely to keep its key interest rate at a record low for the third straight meeting, as policy makers are caught between a fragile economic recovery and faster-than-expected inflation. (Photo by Dado Galdieri/Bloomberg)