Tail sailing refers to the action of

whale Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. As an informal and colloquial grouping, they correspond to large members of the infraorder Cetacea, i.e. all cetaceans apart from dolphins and ...

s lifting their tails clear of the water for long periods of time. The process is rarely observed by humans, and the precise motivation for this phenomenon is unknown. It is thought that whales either undertake this activity to catch the wind and 'sail' through the water, or as a method to cool down. A third theory suggests that the whale is feeding close to the sea floor. Scientists believe that tail-sailing is fairly common amongst certain species, such as the

Southern right whale The southern right whale (''Eubalaena australis'') is a baleen whale, one of three species classified as right whales belonging to the genus ''Eubalaena''. Southern right whales inhabit oceans south of the Equator, between the latitudes of 20 ...

References

Whales Cetology Mammal behavior Aquatic locomotion {{whale-stub