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)

The fourth annual BigPicture Natural World Photography Competition aims to celebrate the diversity of life on Earth, and encourages people to protect and conserve it. Here: “The Salmon Catchers”. Terrestrial Wildlife. To capture this view of a mother grizzly bear and her cub, photographer Peter Mather set up a camera trap on a log that he knew the bears tended to traverse while fishing for salmon, in the Yukon River watershed in Canada. (Photo by Peter Mather/BigPicture Natural World Photography Competition 2017)

A lynx cub that followed a villager in the forest, is fed by a mother and her son for 2 days at the Koyulhisar district of Sivas, Turkiye on October 4, 2023. After 2 days, the lynx cub was taken under protection by the Sivas Department of Nature Conservation and National Parks teams. (Photo by Serhat Zafer/Anadolu Agency via Getty Images)

Tuvalu-registered OS 35 cargo ship lies on the seabed, offshore Gibraltar, Tuesday, August 30, 2022. Gibraltar authorities say they have beached a cargo ship to prevent it from sinking after it collided with a liquefied natural gas carrier in the bay of Gibraltar. (Photo by Europa Press via AP Photo)

A Tyrannosaurus Rex dinosaur costume runs on the field as young boys play an exhibition soccer match during halftime of the MLS soccer game between the Los Angeles Galaxy and Seattle Sounders FC in Carson, California May 26, 2013. The dinosaur was on the field to promote the Natural History Museum of Los Angeles County. (Photo by Danny Moloshok/Reuters)