First look: Wildlife Photographer of the Year 54

When Adam first spotted the Titiwangsa horned tree lizard on the road near his home in the mountains of Pahang, Malaysia, it was in a furious battle with a venomous Malaysian jewel centipede.

When the lizard finally overpowered the centipede, Adam crawled towards it for an eye-level portrait. The species is one of Adam's favourite lizards. It is also highly sought after by poachers for the pet trade, and Adam and his father do regular anti-poaching walks. So once this individual had finished its meal, Adam made sure it ran back into the safety of the forest.

Tony travelled to Japan's remote Sado Island to capture this image of an Asian sheepshead wrasse.

Individuals of this species start out as females, and when they reach a certain age and size (up to a metre long) they can transform into males.

Long-lived and slow-growing, the species is vulnerable to overfishing. It favours rocky reefs in cool waters in the Western Pacific, where it feeds on shellfish and crustaceans, though little more is known about it. 

A lioness drinks from a waterhole in Zambia's South Luangwa National Park. She is one of the Mfuwe Lodge pride, made up of two males, five females and five cubs.

Isak had been keeping watch on them while they slept off a feast from a buffalo kill the night before. Lions kill more than 95% of their prey at night and can spend between 18 and 20 hours each day resting.

When this female got up and walked off, Isak anticipated that she might be going for a drink, and so he headed for the nearest waterhole.

Isak positioned his vehicle on the opposite side of the waterhole, close to the edge, steadying his long lens on a bean bag. The lioness appeared through the tall grass and hunched down to drink. Isak caught her gaze and her tongue lapping the water, framed by the wall of lush green.  

In a remote forest, high in the Himalayas of central Bhutan, a Bengal tiger fixes his gaze on the camera. The path he treads is part of a network linking the country's national parks, corridors that are key to the conservation of this endangered subspecies but unprotected from logging and poaching.

Emmanuel and a team of rangers climbed rugged terrain, with enough kit to set up eight still and eight video cameras along one route, in the hope of glimpsing a tiger pass by (there were just 103 in Bhutan at the last count).

Concentrating on areas with previous tiger records, they searched for evidence of recent use (tracks, scratches and faeces) and Emmanuel installed cameras on wooden posts in the most likely spots. After 23 days (and hundreds of false triggers by leaves and high winds), he hit the jackpot: a magnificent male tiger, and from his distinctive stripe pattern, one previously unrecorded in Bhutan. The tiger inspected the kit closely before disappearing into the forest.

In a shallow tidal pool, a colourful cluster of detached fronds of egg wrack and bladder wrack form an abstract pattern against white sand. They have been washed off the rocks surrounding Mangersta Sands, on the Isle of Lewis in Scotland's Outer Hebrides.

The air-filled bladders of these marine algae keep their fronds floating and exposed to light so they can photosynthesize. Where they are very exposed to wave action, the seaweed may have no bladders, reducing the risk of being swept away if their holdfasts are ripped from the rocks.

Using a polarizing filter to avoid reflections and to reveal details beneath the surface, Theo experimented with focal lengths while waiting for the wind to stop causing ripples and moving the seaweed. He finally settled on this composition, to reveal 'the simple beauty of structures and patterns created by nature itself'.

Valter came across these walruses feeding near an island in the Norwegian archipelago off Svalbard. Putting on his wetsuit, and using a couple of monopod poles and a float to extend his camera in front of him, Valter slipped into the icy water.

Immediately, a few curious walruses began swimming towards him. Although clumsy on land, these giants moved with ease and speed in the water. Keeping at pole's length, he was able to take this intimate portrait of the distinctive whiskered faces of a youngster and its watchful mother.

Walruses use their highly sensitive whiskers and snout to search out bivalve molluscs (such as clams) and other small invertebrates on the ocean floor. In the cold water, their thick protective skin appears grey when blood flow to its surface is reduced, but darker, reddish‑brown when they are out of water and have warmed up. The tusks are not used for feeding but for display among the males, for defence against polar bears and for hauling themselves out, especially onto sea ice. They will rest on ice floes between bouts of feeding and even give birth on them.

This Sargassumfish couldn't hide among the litter. The nearby frond of Sargassum seaweed was a far cry from the free-floating rafts of the seaweed that more normally shelter this frogfish.

A master of camouflage and an ambush predator, the Sargassumfish stalks its prey on claw-like fins through the fronds of these floating islands, concealed by its tan colour and feathery outline.

Greg spotted this individual when returning from a dive on the biodiverse reefs of the Indonesian archipelago of Raja Ampat. It is an area of the western Pacific Ocean where strong currents converge, bringing with them nutrients that sustain the rich biodiversity. The currents also collect and concentrate anything else that floats - including some of the millions of tonnes of plastic that end up in the oceans each year.

As soon as he saw Emily, the sun bear hurried to the front of his filthy cage. He was just one of several sun bears kept behind the scenes at a zoo in Sumatra, Indonesia, in conditions Emily says were 'appalling'.

Sun bears are the world's smallest bears, and they are now critically endangered. In the lowland forests of Southeast Asia, they spend much of their time in trees, eating fruit and small animals, using their claws to prise open rotten wood in search of grubs.

They are threatened by deforestation and the demand for their bile and organs for traditional Chinese medicine. People involved in illegal logging and clearance for oil palms are also linked to animal trafficking. When this sun bear saw the keeper, he started screaming. It was a chilling noise.

When an Anchieta's cobra reared its head and moved towards two meerkat pups near their warren on Namibia's Brandberg Mountain, the rest of the pack reacted almost instantly.

Rushing back, the 20-strong group split into two: one group grabbed the pups and huddled a safe distance away, the other took on the snake. The mob edged forwards, growling. When the snake lunged, they sprang back. This was repeated for about 10 minutes.

Tertius had a ringside seat from his vehicle. Focusing on the snake's classic profile and flicking tongue, he also caught the expressions of fear and aggression among the meerkats. Finally, the cobra gave up and disappeared down a burrow into the warren. The meerkats reunited and scurried away.

Adrian was exploring a derelict schoolroom when a red fox trotted in, perhaps curious about the human or perhaps just on its rounds.

It stopped briefly on the carpet of child-sized gas masks, just long enough for a picture, and then exited through a broken window.

The school in Pripyat, Ukraine, was abandoned in 1986 following the catastrophic explosion at the Chernobyl nuclear power plant, just three kilometres away. It was the worst nuclear accident in history, spreading radioactive fallout across Europe.

The city lies within the 30-kilometre exclusion zone which only accredited individuals can enter. In the absence of humans, the forest is moving back in. Animals such as wild boar, deer, moose and lynx are making a comeback, and there are even sightings of brown bears and wolves. Though there were areas of the zone that Adrian was advised not to enter because radiation levels were still too high, and though the long-term effect of radiation on the animals is far from clear, wildlife appears to be thriving.