A male deer barks at dawn during the annual deer rutting season at Richmond Park in London, Britain, October 9, 2016. (Photo by Toby Melville/Reuters)

Khan, a five-year-old male White Bengal tiger, looks on inside an open-air cage at the Royev Ruchey zoo in Krasnoyarsk, Russia, October 21, 2016. (Photo by Ilya Naymushin/Reuters)

A veterinarian from the zoo of Besancon feeds “Soa”, a female crowned sifaka, in Besancon, eastern France, on February 18, 2019. The crowned sifaka is a critically endangered species from Madagascar. There were only 6 females over 20 individuals living in 7 zoos worldwide end of 2018. (Photo by Sébastien Bozon/AFP Photo)

A hunter holds a shot female pheasant next to his dog “Lola”, a Deutsch female Kurzhaar, during the first day of the Italy hunting season in Castell'Azzara, Tuscany, central Italy, September 20, 2015. The number of hunters in Italy has been decreasing, from 1,701,853 in 1980 to 751.876 in 2007, with a percentage reduction of 55.8%, according to the latest available numbers from the national statistics bureau ISTAT. (Photo by Max Rossi/Reuters)

A woman stands in a gift shop in central Rason city, part of the special economic zone northeast of Pyongyang, in this August 30, 2011 file photo. North Korea is a militarized, male-dominated society, but it is women who are making the money as the insular nation allows an unofficial market-based economy to take shape. (Photo by Carlos Barria/Reuters)

A chimpanzee in the Osnabrück Zoo in Lower Saxony makes contact with a small zoo visitor sitting in front of a pane on September 1, 2020. The two males Lobo and Lome moved from Leipzig Zoo to Osnabrück Zoo to strengthen the social structure of the existing group. (Photo by Friso Gentsch/dpa)

A male Philippine eagle named Geothermica is seen in an exclosure at Jurong Bird Park in Singapore on November 27, 2019. Singapore unveiled two Philippine eagles at its main aviary November 27, the first breeding pair of the critically endangered raptors to be brought outside their native country as part of a conservation plan. (Photo by Roslan Rahman/AFP Photo)

Buyan, a male Siberian brown bear, is given a shower by a zoo employee in his enclosure at the Royev Ruchey zoo in Russia's Siberian city of Krasnoyarsk June 24, 2014. The Siberian city has been experiencing temperatures of around 30 degrees Celsius over the last week. (Photo by Ilya Naymushin/Reuters)