A polar bear swims in its enclosure at the Budapest Zoo September 23, 2009. REUTERS

A young athlete is seen after diving during a training session at a training school in Shanghai February 14, 2008. REUTERS

Anabel Veloso, dancer from the flamenco company "Deje Flamenco", performs during the flamenco show "Nacidos del Mar" (Born of the Sea) at Roquetas de Mar Aquarium in southeast Spain September 16, 2009. REUTERS

A man dives in the Mediterranean sea in the Balearic island of Mallorca July 8,2006. REUTERS

Aurora, a 20-year-old Beluga whale, swims with her newborn calf after giving birth at the Vancouver Aquarium in Vancouver, British Columbia June 7, 2009. Aurora was in labor for about three hours before delivering the calf. REUTERS

A scuba diver approaches a swirling school of giant barracudas at Barracuda Point off the Malaysian island of Sipadan December 9, 2008. REUTERS

The right hand of a young visitor is silhouetted against a jellyfish exhibition hall at the Ocean Park aquarium-amusement complex in Hong Kong January 20, 2008. REUTERS

People swim in a swimming pool at a marina in Singapore November 3, 2007. REUTERS

A sea lion named Kalle swims in icy pool in Ljubljana's zoo January 15, 2009. REUTERS

Diver Brad Norman photographs a whale shark at Ningaloo Marine Park, off the coast of Western Australia, in this undated handout picture made available November 29, 2007. REUTERS

Amateur triathletes start the swim of the Ironman World Championship Triathlon in Kailua-Kona, Hawaii October 11, 2008. REUTERS

German marine ecologist Judith Denkinger poses for a picture as she demonstrates how she collects underwater temperature off the San Cristobal island in Galapagos Islands August 23, 2009. REUTERS

Federica Pellegrini of Italy is seen from underwater in the women's 200m freestyle swimming final at the World Championships in Rome July 29, 2009. REUTERS

A tourist dives in a cage partially immersed in a crocodile pen in Crocosaurus Cove in Darwin August 28, 2008. REUTERS

Katherine Nichols of Honolulu trains before the Ironman World Championship triathlon in Kailua-Kona, Hawaii, October 12, 2007 REUTERS

A diver examines the deck gun of a Soviet submarine that was sunk during Finland's Winter War in 1940 in this handout photo made available June 9, 2009. REUTERS

Corals are seen at the Great Barrier Reef in this January 2002 handout photo. REUTERS

A clown fish swims among the anemone at Kapalai, off the Malaysian island of Sipadan in Celebes Sea, east of Borneo, March 12, 2007. REUTERS

Scuba divers swim with a school of barracuda off the Malaysian island of Sipadan in Celebes Sea, east of Borneo, December 7, 2007. REUTERS

People swim with wild dolphins near Mikura island, 200km south of Tokyo, August 3, 2008. REUTERS