Swimmers in fancy dress splash as they participate in the New Year's Day Loony Dook swim at South Queensferry, Scotland January 1, 2015. (Photo by Russell Cheyne/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)

Nick Bull captured the Geminid meteor shower above Stonehenge in Wiltshire, UK on December 14, 2023. (Photo by Nick Bull/Picture Eexclusive)

A family pose for a picture as thousands of redheads fill a Dutch city Breda to celebrate International Redhead Day event in Breda, The Netherlands on Sunday, 4 September 2016. Every year natural redheads from more than 80 countries come together at “Roodharigendag” annual weekend long festival to celebrate their ginger genes. The event also holds the world record for the largest number of natural redheads being in one place. (Photo by Akmen/London News Pictures)

A passenger plane comes into land over a field containing horses at Heathrow Airport on August 11, 2014 in London, England. Heathrow is the busiest airport in the United Kingdom and the third busiest in the world. The airport's operator BAA wants to build a third runway to cope with increased demand. (Photo by Peter Macdiarmid/Getty Images)

Air Force One casts its shadow over homes as it comes in to land in Allentown, Pennsylania with U.S. President George W. Bush aboard in this October 1, 2004 file photo. (Photo by Jason Reed/Reuters)

Artist Jason deCaires Taylor’s Museo Atlantico, off Lanzarote, is peopled with concrete casts of refugees and people taking selfies. Drowned world: welcome to Europe’s first undersea sculpture museum. Here: The Raft of Lampedusa, Taylor’s modern-day concrete echo of Géricault’s The Raft of the Medusa. The work has particular significance given the huge movement of refugees across the sea to Europe – and the frequent fatalities that result. (Photo by Jason deCaires Taylor)

A passenger waits after his train arrived in Nouadhibou, Mauritania’s second largest city and the main export port for the country’s iron ore industry, on June 25, 2014. The mining company’s employees proudly call their firm the lung of their nation's economy and the train that ferries the ore to the coast stretches some two kilometres, making it one of the world's longest. SNIM mines black iron ore in the northern town of Zouerate, a remote desert location which nevertheless attracts people from all over the country looking for work. (Photo by Joe Penney/Reuters)