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)

These Eurasian Otters seem ready for any danger as they all stand up on thier hind legs alert to any threats near to the English river bank. Amateur photographer and retired MOD worker Tony Moir, 57, spotted the otters whilst looking for kingfishers to photograph near the river Trent in East Yorkshire, UK. He was able to take just a couple of pictures before the excited animals spotted the photographer and ran away. (Photo by Tony Moir/Solent News)

A photographer takes a snapshot of the reflection of balloons as they take off from Balloon fiesta park in Corrales, N.M., near a north diversion channel reservoir Wednesday, October 7, 2015. (Photo by Roberto E. Rosales/Albuquerque Journal via 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 fantastic landscape of Bagan in Myanmar features hundreds of temples and pagodas as far as the eye can see. Experiencing this sight at dawn from the basket of a hot air balloon will remain engraved in my memory for ever. Mick Ryan, judge – What a magical photograph and place. The Buddhist temples and pagodas fill the plains of Bagan in Myanmar at sunrise… the golden hour providing beautiful light to illuminate the retrogression of the temples and balloons toward a misty, mountainous distance. An excellent, exotic photograph that makes you want to book a flight”. (Photo by Alastair Swan/The Guardian)

Britain's Catherine, Duchess of Cambridge, shelters from the rain under an umbrella as she arrives at the London School of Economics to mark the launch of The Royal Foundation Centre for Early Childhood, where she took part in a roundtable discussion on the Centre's inaugural report, “Big Change Starts Small” which was released today, in London on June 18, 2021. (Photo by Richard Pohle/Pool via AFP Photo)

Lord Roscoe the cat runs through the crocuses on the lawns at the National Trust's 17th-century Ham House and Garden in Richmond, London on Monday, March 6, 2023. In recent years more than 500,000 bulbs have been planted to create a spectacle for visitors and to attract bees, butterflies and other pollinating insects. (Photo by Kirsty O'Connor/PA Images via Getty Images)

Elaine Vandiver shares a moment with a two-year old alpaca as they touch noses as she washes him at her farm at 1560 Stateline Road Monday, May 11, 2015, in Walla Walla, Wash. (Photo by Michael Lopez/Walla Walla Union-Bulletin via AP Photo)