A-fishin' in the water, uh-huh.
I don't know her name,
She's the fisherman's daughter, uh-huh.
Come on down to my boat baby.
Come on down where we can play.
Come on down to my boat baby.
Come on down we'll sail away."
(So far, so good. Boy meets girl, girl invites girl to ride in his boat.)
Like she wants to come with me, uh-huh.
But she's tied to the dock,
And she can't get free."
She's what? Tied to the dock? Can't get free? What's going on, has she been kidnapped?
No, the truth is even worse -- "Father never lets her out of his sight."
So, this poor young woman is tied to the dock by her own father, but now that this young man knows of her plight surely he'll rescue her, right?
Well, yes, eventually:
"Soon I'm gonna have to get my knife,
And cut that rope, cut that rope.
So we can go fishin' in my little red boat,
Make you happy in my little red boat."
Soon?? How about now, you spineless beach bum? Come on, man, This girl is being abused. Do the right thing, either cut her free or call the police or the Coast Guard or somebody. Don't make it worse by taunting her, telling her how much fun she could be having if she was only free.