'Cycle War' was taken in Egypt and shows Norton 16H motorbikes loaded in the SS Thistlegorm, with soldierfish schooling above.
"I've had this image in mind for a few years, but it is impossible to capture in one photo, because there is not space inside the wreck to photograph this scene in a single frame," explains Friedrich. "My solution was take a series of pictures and stitch them together as a panorama."
Chair of the judges, Peter Rowlands, added: "This is a quite extraordinary shot which must be viewed as large as possible. The artistic skill is in visualising such an image, and the photographic talent is in achieving it."
Grant Thomas won the title of British Underwater Photographer of the Year. His image of swans, titled 'Love Birds', was taken in Scotland's Loch Lomond.
Waiting in the waters of the lake, Thomas's patience paid off. "The swans were searching for food. I just had to wait for that perfect moment of synchronicity."
The competition had 11 categories, testing photographers with themes such as Macro, Wide Angle, Behaviour and Wreck Photography, as well as three categories for photos taken in British waters.
Abdul Rahman Jamaludin's image of sea slugs features a surprising backdrop of a moray eel, which swam into the reef as he was taking his image.
Leicester-based Tony Stephenson managed to find these pike in the quarry at Stoney Cove, a popular scuba diving site.
When a whale is spyhopping, it emerges from the water vertically, pausing in its position. Greg Lecoeur captured this humpback as it moved its pectoral fin towards the camera.
Shane Gross's photograph was taken in a pond with a very high density of seahorses, yet he was still amazed that he managed to capture these three together, backlit and surrounded by plankton.
Shark behaviourist Cristina Zenato has been studying Caribbean reef sharks near Freeport in The Bahamas for more than 24 years. The unique bond between her and the sharks allows her to get close to them, enabling this impressive image by Fan Ping.
Although Songda Cai has had many encounters with eels, this is her favourite image of the creature, looking at her camera from inside its coiled body.
A fish had managed to wedge itself between the bell and the tentacles of a jellyfish, and the two were moving along together. This strange combination turned towards Scott Gutsy Tuason after he had taken 20 photos, and he was able to get this fantastic shot.
It took two days of standing in shallow waters from 05:00 to 08:00 for Filippo Borghi to get this image of a cormorant diving for fish in the Izu Peninsula, Tokyo.
Tanya Houppermans swam on her back underneath this sand tiger shark, trying not to startle it as millions of tiny fish swam around it. As she moved with the shark through the water, the fish parted and the underside of the shark was revealed.
These humpback whales were swimming by the Haʻapai islands of Tonga when Simone Matucci and his wife were diving. "It was the most wild and incredible thing I have probably witnessed in my entire life" he says.
Kurile Lake in Russia has a very high concentration of bears, which is why Mike Korostelev placed his remote camera in its shallow waters. He captured this bear extremely close up, hunting for salmon.
Borut Furlan shot seawater crocodiles in Cuba in the low evening sunlight, capturing their reflections in the still waters of the surface.
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