That's an urban myth about the rude names.

Aboard his ship, Captain Pugwash is a jovial and rather innocent pirate certainly a stark contrast to the scheme and rather underhand personae of fellow pirate but mortal enemy Cutthroat Jake. Aristophanes liked to use the word. No good will come of this, mark my words. The investigation will also look at other 1970s animation after claims that ‘Mary, Mungo and Midge’ was secretly used as a verb. In his 1992 book The Golden Age of Children's Television, Geoff Tibballs mentioned that some of the names in the BBC cartoon Captain Pugwash were a little rude. We accept that it is untrue that there ever were any such characters. I'd like to put this urban legend well and truly to rest as everyone i ever ask seems to think that it was in fact true: TheCaptain Pugwash cartoon, which originally ran on the BBC between 1958 and 1967, is widely believed to have featured characters with risqué maritime names such as Master Bates, Seaman Staines, and Roger the Cabin Boy. Captain Pugwash originally appeared in the first 12 issues of Eagle comic, before moving to television. Broadsheet and tabloid newspapers printed the story. 9. Horatio Pugwash is the cowardly, genial and rotund pirate captain of the Black Pig.
Isbael Ryan said her father’s childlike innocence was lost after student newspapers in the 1970s created malicious rumours about the supposed smutty names of the TV show’s characters. And the urban myth turned into “truth”. These stories were entirely invented by a student rag. Their actual names were Tom, pirates Willy and Barnabas, and Master Mate. The bumbling Captain was brought to … It was an urban myth that the names of the characters were Master Bates, Seaman Staines & Roger the Cabin Boy. His enemy was Cut-Throat Jake who was captain of the Flying Dustman. There is a persistent urban legend, originating in the now-defunct UK newspaper the Sunday Correspondent, which ascribes sexually suggestive names - such as Master Bates, Ben Dover, Seaman Staines, and Roger the Cabin Boy - to Captain Pugwash 's characters. It was Master Mate and the cabin boy wasn't called roger, it might have been Tom. He gave the money from the courts to lifeboat charities. The only thing close to a rude name was one of the pirates being called pirate Willy. (British comedy) It's frequently claimed that some of the characters in the children's show Captain Pugwash had somewhat suggestive names: "Master Bates", "Seaman Staines" and "Roger the cabin boy".

The lovable pirates had been smeared! The children's animation was written, illustrated and produced by John Ryan. Even the word ‘Pugwash’ was suspected of being obscene (a sexual act in Australia). Created by John Ryan, Captain Pugwash began as a comic strip in The Eagle #1. The children's animation was written, illustrated and produced by John Ryan. When I was a student, everyone I knew joked about the nautical double entendres that went over their heads when they were kids. Given the vaguely puerile names of characters like 'Master Mates' and 'Willy', it's origin probably comes from Ancient Greece: 'Captain Pugwash' sounds and looks very much like 'katapugon' (καταπυγων), which means 'bugger'. Author of Pugwash, John Ryan won libel damages from the newspapers.