Filipino mermaid swimming teacher Genevieve Reyes (C) has her tail adjusted by students during a lesson by the Philippines Mermaid Swimming Academy in a private swimming pool in Makati, Manila, Philippines, 15 June 2013. The Philippine Mermaid Swimming Academy (PMSA) was created in 2012 in Boracay by Normeth Preglo of The Philippines and US swimming instructor Djuna Rocha. The swimming lessons were brought to Manila in April 2013. The price for a two-hour class is 37 US dollars. (Photo by Dennis M. Sabangan/EPA)

A participant wearing Kokoshnik, the Russian traditional headwear, walks out of the water during winter swimming festival in the town of Podolsk, south of Moscow, Russia January 5, 2017. (Photo by Maxim Shemetov/Reuters)

A 1964 Amphicar driven by James Spear of Henderson, Nevada is shown on the boat launch after a trip to Hoover Dam during the first Las Vegas Amphicar Swim-in at Lake Mead near Las Vegas, Nevada October 9, 2015. The German-made Amphicar was produced from 1961-1968. (Photo by Steve Marcus/Reuters)

Children attend a swim training session at Hangzhou Chen Jinglun Sport school Natatorium, where Chinese Olympic swimmer Sun Yang and Fu Yuanhui also trained, in Hangzhou, Zhejiang province, China, August 10, 2016. (Photo by Aly Song/Reuters)

A swimmer reacts after finishing his competition in a pool carved into thick ice covering the Songhua River during the Harbin Ice Swimming Competition in the northern city of Harbin, Heilongjiang province January 5, 2015. The swimming competition was held on the official launch day of the Harbin International Ice and Snow Sculpture Festival. (Photo by Kim Kyung-Hoon/Reuters)

These talented turtles have been "snapped" performing for the camera as they practice their synchronized swimming routine. Photographed underwater by Monste Grillo, 36, from Tenerife, Spain, the turtles are seen swimming in unison as well as touching fins as they circle towards the surface. After spending hours in the water off the coast of the Canary Islands in 2012, the photographs capture the gentle nature of the creatures as well as giving a fascinating glimpse into their behavior in the wild. (CATERS NEWS)

Swimmers climb out of a pool carved into the thick ice covering the Songhua River during the Harbin Ice Swimming Competition in the northern city of Harbin, Heilongjiang province January 5, 2014. According to organisers, about 700 swimmers across China took part in the event on the official launch day of the Harbin Ice and Snow Sculpture Festival. (Photo by Kim Kyung-Hoon/Reuters)

The team from France performs their Free Routine during the Synchronized Swimming Olympic Games Qualification Tournament at the Maria Lenk Aquatics Center in Rio de Janeiro, Brazil on March 6, 2016. The tournament is also a test event for the Rio 2016 Olympics. (Photo by Sergio Moraes/Reuters)