Over 1000 New Year revellers, many in fancy dress, braved freezing conditions in the River Forth in front of the Forth Rail Bridge during the annual Loony Dook Swim on January 1, 2012 in South Queensferry, Scotland. Thousands of people gathered last night to see in the New Year at Hogmanay celebrations in towns and cities across Scotland. (Photo by Jeff J. Mitchell/Getty Images)

A girl jumps over a campfire while celebrating Ivan Kupala Night, a traditional Slavic holiday not far from Kiev on July 6, 2013. During the celebration, originating in pagan times, people plait wreaths, jump over fires, and swim naked. (Photo by Sergei Supinsky/AFP Photo)

Bottlenose dolphins swim over visitors in water tank at the Hakkeijima Sea Paradise aquarium-amusement park complex in Yokohama, southwest of Tokyo, Tuesday, July 21, 2015. Temperatures in Tokyo's metropolitan area neared around 96 degree Fahrenheit, or 35 degree Celsius, on Tuesday. (Photo by Shuji Kajiyama/AP Photo)

This photo taken on August 7, 2016 shows mahjong enthusiasts playing mahjong under water in a swimming pool at a diving club in the Chinese city of Chongqing. Only participants with proper diving certification were allowed to take part in the underwater competition. (Photo by AFP Photo/Stringer)

Ukrainians swim in an ice hole as part of the celebration of the Epiphany in Kiev, Ukraine, Monday, January 19, 2015. Orthodox believers celebrate the holiday of the Epiphany on Jan. 19, and traditionally bathe in holes cut through thick ice on rivers and ponds to cleanse themselves with water deemed holy for the day. (Photo by Sergei Chuzavkov/AP Photo)

People dressed as mermaids and mermen take part in the group swim during the MerMagic Convention at the Freedom Aquatic & Fitness Center in Manassas, Virginia on March 4, 2023. The event bills itself as the “World's Largest Mermaid Convention”. (Photo by Joseph Prezioso/AFP Photo)

A caiman swims amidst trash in Canal das Taxas at the Recreio dos Bandeirantes neighborhood in west Rio de Janeiro, Brazil, on November 22, 2023. The urban expansion of the area and the resulting pollution have put the yacare caiman (Caiman latirostris) “in danger of extinction”. (Photo by Tercio Teixeira/AFP Photo)

Swimmers in the Sky Pool, a transparent swimming pool suspended 35 meters above ground between two apartment buildings, during hot weather in Nine Elms, central London on Monday, August 12, 2024. (Photo by James Manning/PA Images via Getty Images)