25 photos from the Wildlife Photographer of the Year contest portray the beauty and vulnerability of life in the wild

Milligan was trekking through the Loango National Park forest in Gabon when she saw this chimpanzee.

Her group "heard the call of a chimp first, then the leaves around them started to rustle, and a group of chimpanzees appeared," the Natural History Museum wrote on its website.

"As she [Milligan] peered through her viewfinder, a large male paused and looked down at the group, craning its neck forward, and its eyes seemed to widen as if to get a better look," the museum added.

Photographer Jess Findlay spent several nights observing an owl's behavior near Vancouver, Canada, to plan this shot.

The museum described how he used an invisible beam to trigger a flash when the bird left the barn, while a slow shutter speed captured the "ambient light cast on the clouds and barn."

"It was a complicated setup but, to Jess's amazement, it worked the first time," the museum wrote.

Locals in St Leonards-on-Sea in England had been leaving out food scraps for foxes, "but Ian [Wood] noticed that badgers from a nearby sett were also coming to forage," wrote the museum.

"After seeing a badger walking along the pavement by this wall late one night, he decided to photograph it."

He relied on the glow of a lamppost to light the scene.

"Sue [Flood] watched this Weddell seal from aboard a rigid inflatable boat in Neko Harbour of the Antarctic Peninsula," read the museum caption.

"So as not to disturb its peaceful slumber, Sue used a long lens to record this serene portrait."

Photographer Piotr Naskrecki watched this sengi for weeks at Gorongosa National Park, Mozambique, and noticed it took the same path every day as it searched for food.

Since sengis are "extremely shy and skittish," the museum wrote, Naskrecki used a remote camera to capture this image.

The Natural History Museum wrote that Michel d'Oultremont had hoped for years to take a photo of a stoat camouflaged in the snow — eventually, he got the opportunity in his home country of Belgium.

"He lay in the snow with a white camouflage net covering all but his lens," the museum wrote. "This curious stoat came out of its snowy hole and sat up from time to time, observing its territory just before setting off to hunt."

Photographer Francisco Negroni regularly visits the Villarrica Volcano, one of Chile's most active, in Pucón. Every visit is "quite an adventure — never knowing what the volcano might surprise you with," he told the museum.

In this photo, which was taken during a 10-day trip to the area, he captured the powerful moment the volcano's lava illuminated a stack of lenticular clouds.

Arvind Ramamurthy was taking photos of a wolf pack playing in fields in Bhigwan, India, when "one of them came and sat down at the edge of the agricultural crop, and one by one, four others joined it. They paused for a few seconds before they ran off again, playing and chasing one another." the museum's caption read.

The museum touted this image by Aaron Baggenstos as "a symbol of hope," showcasing how wild animals and humans — in this case, gauchos, or sheep farmers — can co-exist. It was taken in the Torres del Paine National Park, which has promoted ecotourism in the region.

"The gauchos view pumas more positively because they're attracting tourists, which is good for income," the museum wrote.

Meanwhile, the farmers' sheepdogs scare pumas away, forcing them to prey on wild animals, rather than the sheep.

"There is hope that humans and pumas can live alongside one another," the museum wrote.

Red-shanked douc langurs — critically endangered primates only found in Vietnam, Laos, and Cambodia — are known for their red "stockings."

Photographer Ivan Ivanek found a small group of the monkeys after surveying the area for several days.

Then, one evening, "he saw these two mating. Compared to other species of monkey he'd seen mating, it was an unexpectedly gradual and graceful affair!" wrote the museum.

Leue was in a helicopter when he witnessed a striking scene: floodwaters surging towards Kati Thanda-Lake Eyre, Australia's largest inland lake, against a backdrop of a dust storm and rain.

The floodwaters had traveled over 1,600 miles from Queensland toward South Australia.

"Timing was imperative to photograph this once-in-a-decade natural event," the caption read.

Little owls and European rollers come into contact with each other at Kiskunság National Park in Hungary because their nesting areas and food sources are similar.

Máté spent 27 days watching from a hide to capture this interaction.

"During the short mating season, the male roller makes a sport of annoying other birds that stray into its breeding area. It makes a surprise ambush, flying at full speed behind them," the museum wrote, adding, "The little owl seemed nonplussed by the spectacle."

When D'Aurizio visited the San Bartolomeo Valley in the Majella National Park in Italy — where he's been many times — he thought he'd see butterflies and dragonflies.

What he didn't expect, though, was what the museum called "a sad collage of dead insects calmly floating in the water."

"To this day, Carlo has no explanation of why the insects died," its caption read.

Pradhuman watched a pack of wolves on the prowl for something to eat in Yellowstone National Park. Seeing them head for the aspens, he thought it would make a striking image.

"The wolves walked right past these trees and then continued to follow the tree line, eventually disappearing over the hillside," the Natural History Museum wrote.

Williams captured this image of a beluga whale rubbing its body on a river bottom along the Northwest Passage in the Canadian Arctic. It was taken in an inlet, where the waters are shallow and belugas gather to exfoliate their skin, hide from predators, and socialize with each other, according to the museum.

"Nicknamed 'the canaries of the sea,' they produce a series of chirps, clicks, whistles, and squeals that Mark found otherworldly," the museum wrote.

Forsberg, a biologist, approached a whopping crane in Louisiana and moved with "cat-like quickness" to check the bird's health, quickly replacing a faulty transmitter that helps scientists keep track of the birds, per the Natural History Museum.

"This experimental population was reintroduced in Bayou Country in 2011. In the 1940s there were roughly 20 whooping cranes in the region. Since then, numbers have climbed to over 800," the museum wrote.

"In the Norwegian archipelago of Svalbard, a walrus carcass had attracted a female polar bear and her two cubs," wrote the museum.

"But one of the cubs was more interested in playing in the water than eating. The cub was having fun diving under the water and resurfacing, playing with the seaweed and kelp."

Haarberg watched the bear cub attempt to ambush a northern fulmar several times, without success.

Rose captured a beaver's tail smack after years of attempts. She finally found success in a pond in Jackson, Wyoming.

"As she approached the shoreline, a beaver cautiously cruised by after emerging from its lodge," the museum wrote in its caption, adding, "It cocked its tail up and brought it down with a resounding crack."

The tail smacks are a way for the creatures to warn their family members about a newcomer to the area, the museum wrote.

In this photo, Willie Burger van Schalkwyk captured a brave giant ground gecko taking on a southern pale chanting goshawk that was attacking it in Kgalagadi Transfrontier Park in South Africa.

"Unfortunately, there was no hope of survival, but Willie was impressed by the gecko's bravery," the Natural History Museum wrote.

"Northern giant petrels are large seabirds. They're used to flying above the waves for weeks without encountering land," the Natural History Museum wrote in its caption of the photo.

"Samuel [Bloch] was surprised to find this seabird in such a woody environment. Like many other seabirds, it breeds on islands where there are fewer predators."

To avoid disturbing the bird, the photographer clicked this image swiftly from afar.

This photograph shows the moment a honey badger — covered in blood and quills, but undeterred — returned to finish off its prey, a Cape porcupine, in Botswana.

"Honey badgers are famously ferocious," reads the caption.

In the end, the honey badger won the battle, dragging the porcupine to its den, the museum wrote.

Kortler was on a night dive near Komodo Island in Indonesia when he saw a decorator crab on top of a sea squirt.

"The sea squirt provided the crab the perfect stage to feed on drifting plankton," the museum wrote in its caption.

Kortler used flash photography, creating the effect of spotlighting the crab.

Premel captured a Surinam golden-eyed tree frog puffing out its cheeks as it prepared to call for a mate in French Guiana's first rains.

"The call of the Surinam golden-eyed tree frog is so powerful it can be heard hundreds of meters away," the museum wrote.

Brinkmann captured this striking image of a songbird against fairground lights in Münster, Germany.

"During a popular fair in Münster called the Send, an interesting atmosphere arose behind the castle," the museum wrote. "The evening mood was gentle, and Christian [Brinkmann] had singing birds on one side and party music on the other.

"In front of the fairground lights, this Eurasian blackbird posed for its song."

Farmers in the Somali Region capture cheetah cubs, accusing them of harming their livestock, and sell them to traffickers. If the traffickers are unable to sell them, the cheetahs are killed, and their parts are sold for Chinese bone wine and other products.

This cheetah cub "was captured from her home plains" and was then "transported for several days on the back of a camel to the northern coast of Somaliland," the museum wrote.

"After hissing at the camera, the cub started chirping, calling out for its mother," it added.