A baby hippo swims under the water in its enclosure at Prague Zoo, Czech Republic, February 24, 2016. The baby was born on January 28, and is yet to be named. (Photo by David W. Cerny/Reuters)

Karolina Kluskova of the Czech Republic formed one part of an artistic swimming duet at the European Games at Aquatics Centre in Oswiecim, Poland on June 22, 2023. (Photo by Sarah Meyssonnier/Reuters)

This picture taken on September 11, 2023 shows Moon Jellyfish (with rings) and Sting Jellyfish (yellow-orange inside) among a smack of a several thousand swimming off Seglvik, in northern Norway. (Photo by Olivier Morin/AFP Photo)

A diver dressed in a Santa Claus costume swims at the Lotte World Aquarium in Seoul, South Korea, Monday, December 23, 2024. (Photo by Ahn Young-joon/AP Photo)

Neutral athletes Mayya Doroshko and Tatiana Gayday compete in the women's duet technical preliminary of artistic swimming at the World Aquatics Championships in Singapore, Friday, July 18, 2025. (Photo by Vincent Thian/AP Photo)

A swimmer disguised as Superman dives into the lake during the 78th “Coupe de Noel” (Christmas cup) swimming race in the Lake Geneva, on December 18, 2016 in Geneva. More than 1800 participants took part in the event, a 12-meter-long swimming off the Geneva's bank in the 7 degrees Celsius cold water. (Photo by Fabrice Coffrini/AFP Photo)

To mark Halloween, 150 teens descended upon a swimming pool in Essex to help mobile network giffgaff recreate the famous Tomatina tomato fight... only this time, with blood and guts. Different takes #giffgaffguts. On October 18, 2013 in Dagenham, England. (Photo by Dave J. Hogan/Stringer for giffgaff)

Polar Bear club swimmers take their annual swim in the sea at Coney Island in New York City on January 1, 2014. (Photo by Curtis Means/ACE/INFphoto.com)