Grey seals show their playful side while swimming off the English coast, UK in the last decade of May 2025. (Photo by Brian Matthews/Solent News)

A diver dressed in a Santa Claus costume swims with a penguin at Sunshine Aquarium during preparations for the upcoming Christmas special event in Tokyo on December 1, 2025. (Photo by Kazuhiro Nogi/AFP via Getty Images)

Participants of the 77th edition of the annual Christmas swimming 'Coupe de Noel' jump into the waters of Lake Geneva, in Geneva, Switzerland, 20 December 2015. More than 1,540 men and women braved the water temperature of just 8 degrees Celsius as they swam a 120 meters distance at the traditional Christmas swimming in Geneva. (Photo by Salvatore Di Nolfi/EPA)

An athlete dressed as a clown jumps into the Mediterranean sea as he takes part in the Copa Nadal in the Spanish port of Barcelona in Barcelona, Spain, Sunday, December 25, 2016. The Copa Nadal (Christmas Cup) is a traditional swimming competition that takes place in Barcelona every December 25th, where participants swim 200 meters in the open sea in the port of Barcelona. (Photo by Manu Fernandez/AP Photo)

Atsushi Abe and Yumi Adachi from Japan perform in the synchronised swimming mixed duet technical routine preliminary at the Aquatics World Championships in Kazan, Russia July 25, 2015. (Photo by Michael Dalder/Reuters)

Members of Team Italy are seen underwater as they perform in the synchronised swimming team free routine preliminary at the Aquatics World Championships in Kazan, Russia July 28, 2015. (Photo by Michael Dalder/Reuters)

A member of a winter swimming club wears flippers during the celebration of Maslenitsa, also known as Pancake Week, a pagan holiday, marking the end of the winter, in Novosibirsk, Russia. (Photo by Alexandr Kryazhev/Sputnik/Profimedia)

Female seal “Lotte” swims in a pool of her enclosure at the zoo in Rostock, northeastern Germany, on September 27, 2019. (Photo by Bernd Wuestneck/dpa/AFP Photo)