Informant – “Dolphins are considered good luck when they swim with the ship. And it’s bad luck to kill a dolphin.”
JK – “Where does this belief come from?”
Informant – “I just think that dolphins are friendly to humans. They have a long history of…there’s stories of them chasing sharks away and swimming with humans. They are sweet creatures and really intelligent. That level of intelligence demands respect.”
JK – “Where did you hear it from?”
Informant – “I just grew up with that. My father would tell me about dolphins. And there have been a couple of times in my life where I’ve actually seen it. They’ll play in the wake of the ship. It’s really neat.”
There seems to be very logical reasons for this superstition. So much so, that it hardly seems superstitious. Dolphins are historically friendly/helpful creatures, so a pod following your ship is definitely a good thing. It’s hard to think of a valid reason to kill a dolphin, so it makes sense why doing so would be seen as bad luck.