Bloodthirsty by Thomas P. Peschak, Germany/South Africa — winner, Behaviour: birds. When rations run short on Wolf Island, in the remote northern Galápagos, the sharp-beaked ground finches become vampires. Their sitting targets are Nazca boobies and other large birds. The finches rely on a scant diet of seeds and insects, which regularly dries up, so they drink blood to survive. ‘I’ve seen more than half a dozen finches drinking from a single Nazca booby,’ says Tom. Rather than leave their nests the boobies tolerate the vampires, and the blood loss doesn’t seem to cause permanent harm. (Photo by Thomas P. Peschak/2018 Wildlife Photographer of the Year)

A 6-month old female giant panda cub, an offspring of Xing Xing, formerly known as Fu Wa and Liang Liang, formerly known as Feng Yi, plays at the Giant Panda Conservation Center at the National Zoo in Kuala Lumpur, Malaysia, Thursday, February 18, 2016. (Photo by Joshua Paul/AP Photo)

In this photo taken on Monday, January 5, 2015, a mallard duck attempts to walk on a frozen pond in Yukon, Okla. (Photo by Steve Gooch/AP Photo/The Oklahoman)

A dog is kept at a pen at the newly opened Central Zoo in Pyongyang, North Korea, Tuesday, August 23, 2016. One of the most popular attractions at the zoo might come as a surprise to foreign visitors. Just across the way from the hippopotamus pen and the reptile house, dozens of varieties of dogs, including schnauzers, German shepherds, Shih Tzus and Saint Bernards – are on display in the “dog pavilion”. (Photo by Dita Alangkara/AP Photo)

A Thai Marine instructor drinks a cobra's raw blood after killing it as he gives instruction to US Marines and South Korean Marines during jungle survival training as part of the multinational joint military exercise Cobra Gold 2018 at a Force Reconnaissance Battalion camp in the Royal Thai Naval Base, Sattahip district, Chonburi province, Thailand, 19 February 2018. (Photo by Rungroj Yongrit/EPA/EFE)

A zoo employee carries three-month-old female giant panda cub, born to mother Liang Liang and father Xing Xing, on display to the public for the first time at the national zoo in Kuala Lumpur, Malaysia, November 17, 2015. (Photo by Olivia Harris/Reuters)

A person takes a picture of the “Temple”, a 21-foot painted bronze sculpture from 2008, by British artist Damien Hirst, as the spread of the coronavirus disease (COVID-19) continues in the Alpine resort of St. Moritz, Switzerland February 25, 2021. (Photo by Arnd Wiegmann/Reuters)

Yuandudu, a camera-shy panda cub, covers her eyes in Beauval ZooParc in France in November 2021. The three-month-old and her twin are fed once each by their mother every day, taking 150-200g of milk per feed. In between they have one bottle feed per day from the specially trained keepers who were sent from China to supervise their birth and early care. (Photo by Eric Baccega/Naturepl.com/LDY Agency)