A photographer could bear-ly believe his eyes when a bear started waving at him. The friendly animal wandered to the front of his enclosure before sitting back in full view of zoo guests. He then lifts his powerful paw and excitedly waves in an almost human-like way at his new audience. The hilarious encounter was captured by keen photographer Andrey Slepnev, 31, while on a trip to Madrid Zoo, Spain on March 24, 2016. (Photo by Andrey Slepnev/Caters News)

An undated handout picture released on January 10, 2017 by the Issekinicho publishing house shows an inter- species sexual behaviour between a male Japanese macaque and female sika deer, in Yakushima Scientists revealed on January 10, 2017 the “highly unusual” behaviour of a male monkey filmed trying to have sеx with female deer in Japan – a rare case of inter- species nookie. (Photo by Editions Issekinicho/AFP Photo)

It's a 30-day-old Echidna baby, known as a “puggle” – one of only 24 ever bred in captivity. The proud parents are Tippy and Pickle of Australia Zoo. The tiny baby, whose s*x has not yet been identified, hatched from a soft egg and will continue to develop and nurse inside Tippy's warm pouch. (Photo by Australia Zoo/Rex/Sipa Press)

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)

Visitors play in front of hot air balloons during the 2016 International Hot Air Balloon Festival in Taitung, southeast of Taiwan, 01 July 2016. Thirty-one hot-air balloon teams from 14 countries join the six days of competition during the festival, which will run from 01 July to 07 August 2016. (Photo by Ritchie B. Tongo/EPA)

A young girl gives a banana to a tamed baboon on the outskirts of Beira, Mozambique, Sunday, March, 31, 2019. Cholera cases among cyclone survivors in Mozambique have jumped to 271, authorities said. So far no cholera deaths have been confirmed. (Photo by Tsvangirayi Mukwazhi/AP Photo)

Alpacas peek out of their box in Kielnarowa, Poland, June 11, 2014. A total of 35 female and 3 male alpacas were imported from Chile by the Rzeszow University of Information Technology and Management Center Zoo to be used for the therapy of children. Alpacas also provide one of the most expensive wools. (Photo by Darek Demanowicz/EPA)

In this July 12, 2007 file photo, a two-day-old piping plover runs along a beach in the Quonochontaug Conservation Area in Westerly, R.I. (Photo by Steven Senne/AP Photo)