British holidaymaker Sean Chinn captures a crocodile on camera during a dive at the Jardines de la Reina marine park in Caribbean Sea, Cuba. (Photo by Sean Chinn/Caters News Agency)

A dog dressed as UPS worker is seen during the 28th Annual Tompkins Square Halloween Dog Parade at East River Park Amphitheater in New York on October 28, 2018. (Photo by Gordon Donovan/Yahoo News)

Two hippopotamus are fed with pumpkins at the Hanoi Zoo, in Hanoi, Vietnam, 25 October 2018. The zoo has been the home for more than 800 animals of over 90 different species, including three hippopotamus, since it was built in 1976. (Photo by Luong Thai Linh/EPA/EFE)

A cat is presented during “The "3rd International Pursaklar Cat Beauty Fest”, on October 14, 2018 in Ankara. (Photo by Adem Altan/AFP Photo)

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)

An Atlantic seal pup lies amongst the rocks at St Martin's Haven, Pembrokeshire, Wales, Britain October 8, 2018. Seal pups are born with fluffy white non-waterproof coats which they moult out in their fourth week. (Photo by Rebecca Naden/Reuters)

Dead leaf or almost by Guilhem Duvot. Taken in Nován Stráž, Slovakia. Describe what is pictured? A dead leaf grasshopper. How does this image fit with the theme of the competition? The perfect camouflage – nature is amazing. I saw the grasshopper only because it jumped. (Photo by Guilhem Duvot/Royal Society of Biology)

This perfectly-timed GoPro snap captures the moment an angrymagpiecame within inches of a biker, as swooping season takes hold in Australia. The notoriously aggressive bird can be seen flying with its wings tucked in so it looks exactly like a torpedo in the magnificent photograph from Middlemount, Queensland. Retail businesswoman Monique Newton, 53 was riding pillion with a friend when she spied the divebombing bird – but rather than speed off, they slowed down to capture it up close. (Photo by Monique Newton/Caters News Agency)