In pictures: Underwater wonders
Gold, a colourful portrait of a spiny seahorse, taken by Davide Lopresti, in Trieste, Italy, has won this year's UK Underwater Photography Competition.
Lopresti beat entrants from more than 54 countries. He set out to photograph the seahorses to "celebrate their return to areas of the Mediterranean that have been protected from destructive fisheries, such as trawling".
Dan Bolt, from Devon, won British Underwater Photographer of the Year with Catshark Supernova. This award is open to all British residents and nationals.
Pier Mane, from South Africa, won Up and Coming Underwater Photographer of the Year with Three Pillars, taken in the Bahamas.
Marty Engels Dunmore, from Suffolk, won Most Promising British Underwater Photographer with Fired Up, taken on the Kittiwake wreck in Grand Cayman.
Mike Korostelev won the International Wide Angle category with a shot from Kuril Lake, Kamchatka, Russia. "I constructed a cage to keep me safe as I captured the fishing behaviour of the bear," he said.
Thomas Heckmann won the International Wrecks category with a shot from Curacao. "I was unable to descend, because I had to take care of Maja, my five-year-old daughter, who is unable to snorkel by herself. So, my only possibility was a shot from the surface," he said.
Richard Carey won the International Behaviour category with a shot of a turtle eating a jellyfish taken on an early morning dive in the Similan Islands.
Marcus Blatchford won the British Wide Angle award. The judges said: "Whilst this may have been an 'unplanned' photo dive, these two, the model and the photographer, knew exactly what they were doing, either by instinct or design."
Paul Colley, who won the British Compacts category, said: "Whilst trying to photograph trout, during a year-long river project, with a homemade pole-cam, a raft of Mallard ducks muscled in to steal food intended to entice trout to the camera."
You can see more winners and runners-up at the UPY website: www.upylondon.com.