Pete Oxford / Whale shark (Rhincodon typus) and scuba divers seen from below, Cenderawasih Bay, West Papua. Indonesia.

Pete Oxford / Whale shark (Rhincodon typus) and scuba divers seen from below, Cenderawasih Bay, West Papua. Indonesia. Winner of the Man and Nature Portfolio Award in the Terre Sauvage Nature Images Awards Competit...

Pascal Kobeh / 'Lotus', an artificial reef built in 2001 with a steel frame with a mild electrical current which encourages the growth of coral, Ihuru Island, North Male Atoll, Maldives, Indian Ocean. Small reprodu...

Pascal Kobeh / Divers are setting up concrete reef balls to build an artificial reef, Philippines, Sulu Sea. August 2014.

Alex Mustard,Alex Mustard / Divers explore mediaeval mill building, now flooded in Capodacqua lake. Gran Sasso National Park, Abruzzo, Italy.

Alex Mustard / Pair of divers swimming in the blue lagoon at Silfraa, with fractured rocks in the foreground. Thingvellir National Park, Iceland. May 2011. No release available.

Alex Mustard,Alex Mustard / Pair of divers floating in Silfra Canyon, a deep fault filled with fresh water in the rift valley between the Eurasian and American tectonic plates) at Thingvellir National Park, Iceland. May 2011. I...

Alex Mustard / A diver explores Nikulasargj Canyona deep fault filled with fresh water in the rift valley between the Eurasian and American tectonic plates at Thingvellir National Park, Iceland. May 2011. In this ph...

Cheryl-Samantha Owen / West Coast Rock Lobster (Jasus lalandii) observed by diver. Kalk Bay, Atlantic Ocean, False Bay, Valsebaai, Western Cape, South Africa

Michael Pitts,Michael Pitts / Divers on the wreck of the tugboat, 'Tienstin'. Abu Galawa, Red Sea, July 2010

Alex Mustard / Sand diver (Synodus intermedius) portrait on a coral reef, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Nuno Sa / Blue Shark (Prionace glauca) near sea surface and divers in background. Santa Maria, Azores, September.