Members of Brighton Swimming Club brave the early morning temperature to take a dip in the sea east of the pier on January 5, 2022. The club, founded in 1860, is the oldest in England. (Photo by Simon Dack/Alamy Live News)

Team Japan competes during the team free preliminaries of artistic swimming at the 19th FINA World Championships in Budapest, Hungary, Wednesday, June 22, 2022. (Photo by Anna Szilagyi/AP Photo)

This photo taken on November 7, 2023 shows winter swimming enthusiasts taking photos at Beiling Park after snowfall in Shenyang, in China's northeastern Liaoning province. (Photo by AFP Photo/China Stringer Network)

Australia’s Hannah Fredericks competes in the women’s 200m backstroke heats during the Australian Swimming Trials at the Brisbane Aquatic Centre on June 13, 2024. (Photo by David Gray/AFP Photo)

This aerial view shows youths swimming to cool off in the waters of Iraq's Euphrates river during a heatwave, in the district of al-Hindiyah east of Karbala on June 7, 2024. (Photo by Karar Jabbar/AFP Photo)

A person dressed as Santa Claus jumps into the sea during the Copa Nadal (Christmas Cup) swimming race in Barcelona, Spain on December 25, 2024. (Photo by Bruna Casas/Reuters)

“The finless porpoise (Neophocaena phocaenoides) is one of six porpoise species. In the waters around Japan, at the northern end of its range, it is known as the sunameri. A freshwater population found in the Yangtze River in China is known locally as the jiangzhu or «river pig»”. – Wikipedia

Photo: A newly born Yangtze finless porpoise (top) swims with his mother at the Hydrobiology Institute of the Chinese Academy of Sciences on June 3, 2007 in Wuhan of Hubei Province, China. (Photo by China Photos/Getty Images)

“Yokohama Hakkeijima Sea Paradise is an amusement park consisting of an aquarium, shopping mall, hotel, marina and amusement rides. It is located in Kanazawa-ku, Yokohama, Japan. It opened for business on May 8, 1993”. – Wikipedia

Photo: Shoal of sardines and sharks swim in a tank at Yokohama Hakkeijima Sea Paradise on March 19, 2009 in Yokohama, Japan. (Photo by Junko Kimura/Getty Images)