A eight-metre-long Whale shark swims with other fish in a worlds' largest tank with its front panel size of 8.2 metre x 22.5 metre at the Okinawa Churaumi Aquarium on February 26, 2010 in Motobu, Okinawa, Japan. Japan's most popular aquarium attracts more than 2.5 million visitors per year. (Photo by Koichi Kamoshida/Getty Images)

A Sydney Aquarium diver uses a vacuum to clean the gravel in the Great Barrier Reef tank as a Ray Shark swims by September 26, 2006 in Sydney, Australia. The Aquarium is undergoing its annual spring clean to prepare for the school holidays using vacuums, along with sea creatures like Sea Cucumbers, Sea Urchins, Cleaner Wrasse Fish and Sea Stars to help complete the job. (Photo by Ian Waldie/Getty Images)

Vickie Leuenberger (L) practices with a mermaid tail with AquaMermaid founder Marielle Chartier Henault in a pool in Montreal, February 19, 2015. The school teaches kids and adults how to swim wearing mermaid tails, and offers mermaid-themed parties. (Photo by Christinne Muschi/Reuters)

AP photographer Anja Niedringhaus laughs as she attends a swimming event at the 2004 Olympic Games in Athens, August 21, 2004. Niedringhaus, a veteran Associated Press photographer who had covered wars around the world was shot dead and another reporter was wounded on April 4, 2014 when an Afghan policeman opened fire on them in eastern Afghanistan, the news agency said. (Photo by Reuters/Staff)

In this May 8, 2015 photo, sisters Zoraida Infante, left, and Graciela Trujillo pray on Fishermen's Beach before therapeutic swimming in the Pacific Ocean in Lima, Peru. Under overcast skies, the bathers practice thalassotherapy, which derives from the Greek “thalasso”, for “sea”, and draws on the ocean's healing properties. (Photo by Rodrigo Abd/AP Photo)

A dog swims as a resident navigates his boat in a neighbourhood flooded by the Purus river, which continues to rise from days of heavy rainfall in the region, in Boca do Acre, Amazonas state March 14, 2015. According the state civil defense, more than 20,000 people have been left homeless along the Purus river, where incessant rains have flooded the area and caused the river to burst their banks. (Photo by Bruno Kelly/Reuters)

Hannah Maule-ffinch, “Wild Swimmers”, 2020, Hinksey Lake, Oxfordshire. Category: People. The series Wild Swimmers explores how humans are strongest when coming together in the face of adversity. In this photo, Emma and Emma have an amazing bond and friendship, built through their daily ritual of cold swimming in often bracing conditions. (Photo by Hannah Maule-ffinch/Earth Photo 2022)

Underwater photographer of the year 2020 and wide angle category winner: Frozen Mobile Home by Greg Lecoeur (France) in the Antarctic peninsula, Antarctica. Crabeater seals swim around an iceberg. These massive and mysterious habitats are dynamic kingdoms that support marine life. As they swing and rotate slowly through polar currents, icebergs fertilise the oceans by carrying nutrients from land that spark blooms of phytoplankton, fundamental to the carbon cycle. (Photo by Greg Lecoeur/Underwater Photographer of the Year 2020)