The breathtaking winners of the Underwater Photographer of the Year 2023 contest

This shows an Amazon river dolphin, which is also known as "boto" by locals. The biggest challenge of photographing these dolphins is definitely the darkness of the water. You're basically swimming in black tea. This makes lighting a huge challenge.

The shark almost looked as if it was getting fed up with the small fish and it was attempting to shake off the swarm. It would make steep dives and then ascend again right away thrashing its tail, but the fish would just swirl even more densely around the poor shark..I was hoping to spend a bit of time photographing this shark, but after some ups and downs, he disapeared into the depths of the Indian Ocean, an encounter I'll never forget.

On this particular summer evening when I captured the image the underwater conditions were absolutely perfect. Amazing visibility and fantastic natural lighting coming down through the forest onto the sea floor. So I free dived down onto the chalk shelf, I worked on the angles, on the composition and eventually found an image that I felt satisfied with.

A humpback whale dies a slow, painful and agonizing death after having its tail entangled in a ropes and buoys, rendering its tail completely useless. A reflection of what not only our oceans are suffering, but also our planet, the product of man's selfishness and lack of responsibility. Taking this photograph was, for me, the saddest moment I've experienced in the ocean.

'Fade' was taken in Grand Cayman, at a world famous site called Stingray City. I saw this line of stingrays coming in and I thought it might be a good opportunity to get some sort of an action shot or some sort of motion happening. So I fired away, got about 10 shots in the sequence and one of them was 'Fade'.

Walking along a rocky shoreline we would peer under rocks using a probe lens and my camera's LCD screen to check for plainfin midshipman nests. Once found I would lay on top of the barnacle-covered rocks, cutting my elbows, trying to compose images of fish most people have never heard of despite having one of the most interesting lifecycles of any animal. Plainfin midshipman are deep water fish that travel to the intertidal zone to spawn. The males sing to attract females and she will lay as many eggs as his singing deserves before moving on to the next singer. Now, the male has a chance to fertilize the eggs, but only if he is not beaten to the punch by a sneaker male who looks like a female. The singer male will then guard the nest never knowing the kids may not be his. Drama!

We were out scanning targets in June when we saw a very small, but promising sonar blip 230 feet deep. I geared up and jumped in hoping for something special. After some searching, my heart started racing when I first saw fish then the propeller of an almost completely intact, single-engine WW II airplane! It turned out to be a F8F-1 Bearcat, a rare aircraft that Neil Armstrong famously once said was his favorite and has been described as "An Engine With a Saddle." Alone on the first dive with limited bottom time, I took enough photos to build a "draft" model and identify the wreck. Needing a better photogrammetry model for the UPY contest and with deadlines quickly approaching, I booked December 19th and crossed my fingers. We fortunately had epic conditions and I got the photos I needed. It was my last dive of 2022

A couple of coconut octopuses "making love" (mating). I knew that I can find this species of Octopus at one of dive sites near Tulamben village (Bali, Indonesia) and they are active only at night time in that place. I dive there only after 7pm hoping to photograph something unique - their mating. I`ve done more than 30 night dives at the dive site and finally I got lucky. The photo shows the end of their love

The elephant's trunk is one of the most distinctive anatomical features in the natural world and this photo aims to emphasize it. Luckily, he was curious about my camera and was happy to feel it out which gave me the opportunity to capture this perspective despite otherwise bad conditions for an over-under photo (choppy water and poor visibility). In my first attempts, the nostrils were not fully lit because of how close they were to the lens (which was necessary for the intended photographic effect). So I returned at a specific time window when I thought the sun’s angle would be optimal and managed to fully light the nostrils. This added a lot more detail to the key part of the image without which the photo would not be as effective.

The image was taken on the last morning of a five-day trip to Peninsula Valdés in Argentina, in August 2022, under a special permit to enter the water with the Southern Right Whales that gather there between June and December each year.

The mother, who can be seen in the background, accepted our presence and allowed the calf to interact with us. It was very playful but careful not to hit us with it’s tail and seemed to be really enjoying it all – almost as much as we were!

White calves are very rare and referred to locally as “El Blanco” or the white one!

Peninsula Valdés is an incredibly important safe haven and breeding ground for the Southern Right Whales of the southern Atlantic and Argentina has done an excellent job of managing it.

It was, without doubt, my best ever underwater experience!

When I was snorkeling in Marsa Alam I saw countless Klunzinger's Wrasses. One of them was particularly curious and very interested in my lens. I was able to take some good classic wide angle pictures. After a while I figured it would be a good idea to try a long exposure. So I set my camera to the smallest aperture f11, the ISO value to 64 and the exposure time to 1/13s. For this picture, I moved the camera forward a bit while the shutter was released. This created the zoom effect in the lower part of the image. I was very happy with the result.

I have long admired others’ pictures of nudibranchs feeding on the egg coils of other nudibranch species across the world. I’d also seen this nudibranch species, Favorinus branchialis, before, and I knew that it fed in this way, but never seen it in action until recently. I was therefore thrilled to find three large specimens feeding on a big coil of eggs in Shetland, Scotland. The eggs were several inches across, in a wide spiral, so the challenge was to isolate an appealing composition of eggs and nudibranchs.

We were initially interested in this site in Loch Fyne for the fields of Firework Anemones, but of equal interest was an old pipe that had this patterned concrete protective covering along its length. This shallow artificial reef was home to many different species, including some large Langoustines (Nephrops norvegicus) who were seemingly unperturbed by my presence

I had been going back to this spot on Crack rock to capture the variable Blenny for several weeks. He was caring over his eggs inside the crevice so I was trying to capture the point when the eggs were hatching. Being such an inquisitive little chap he was always moving around getting closer to the camera until he got to this point where I took a few shots. I didn't stay too long as I didn't want to have any negative or detrimental affects on the parenting behaviour. It has been great to see an increase in the Variable Blenny around Torbay over the past couple of years.