Underwater hockey started in Britain in the late nineteen-seventies as a way for divers to retain their fitness durning the winter months, when it was too cold to dive.
To begin with, the sport was only played by sub-aqua clubs, but over time specific Octopush (the other name for the sport) clubs started to spring up. Surfers and spear-fishermen proved to be particularly adept.
Whilst there are men's and women's competitions, many teams are mixed, and few (if any) distinctions are drawn between the genders.
Teams are made up of six players, the sticks are called "pushers" and the puck is a "squid"
As a spectator sport, Octopush is very dull, unless you have a clear-sided swimming pool, since all the audience can see is jets of water as players clear their snorkels. However, it is fast paced, exciting, and fun.
In my day, (I played in the early eighties) coming up behind someone and wrenching their mask off was considered a prime tackling technique, but I suspect greater regulation and organisation has put paid to that practice, these days.