According to the show’s writers, when they first came up with the name Gilligan, they intended it to be the character’s last name. When asked what was the character’s first named, they answered Willy.
When the producer met with Alan Hale, they were down to the final candidates. They did not think they would ever be able to find the right skipper in time, and then came Alan Hale. Hale was so good, he got the part on the spot.
According to a few set visitors, Tina Louise did not associate herself with the rest of the cast. Whenever the cast would talk together or eat lunch, Louise would be sitting at the other corner of the room, alone. A part of this can be explained by the fact that when she first signed on to do the show, she was told she would be the main actress.
The set of the island was so close to a highway, on some days they had to shut down productions so the noise won’t get caught by the microphones.