A police officer tries to prevent an anti-government protester from pulling the hair of a woman who is part of group that appeared to show their support for the government during a march of healthcare workers critical of the government, in La Paz, Bolivia, on July 21, 2022. (Photo by Juan Karita/AP Photo)

A man carries a child as he wades trough a flooded road following heavy rains in Strand, Western Cape, South Africa on September 25, 2023. (Photo by Esa Alexander/Reuters)

English television personality, Love Island's Faye Winter is seen painted as a Killer Whale as part of a PETA protest photocall for marine animals in London's Piccadilly Circus on November 18, 2022. (Photo by The Mega Agency)

Grand prize winner: environmental photographer of the year 2023; also 1st place in the humanity v nature category; and winner of the 2023 public award. Lopé national park, Gabon, 2021. An angry elephant tries to defend itself after it was hit by a train that crosses paths the animals use within Lopé national park. Park officials decided the elephant was too severely injured to be saved. After it was killed, the park director distributed the meat to local people. As the forest loses its carrying capacity to sustain its megafauna, this kind of human-wildlife conflict is increasing. (Photo by Jasper Doest/Environmental Photography Award)

Actress Kerry Washington, Harvard University's Hasty Pudding Theatricals' Woman of the Year, throws wine in the face of an actor playing Republican presidential candidate Donald Trump, Thursday, January 28, 2016, as she is roasted in Cambridge, Mass. (Photo by Elise Amendola/AP 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)

Girls prepare to take part in a mermaid lesson in Rio de Janeiro, Brazil May 28, 2017. Women in Brazil are not unique in their affinity for mermaiding. Classes are held as far away as Texas and some folks wonder if mermaiding will be the next fitness craze. (Photo by Pilar Olivares/Reuters)

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)