"There's a fish in the well, mother, mother,
There's a fish in the well.
He's been caught by a man, mother, mother,
And he's been caught by a man."
The type of fish is left intentionally vague to enhance the mysterious and ominous nature of the song.
It's worth noting that "Lord Randall" is an ancient folk ballad, and various versions exist with different details. Some variations might mention the eel being cooked, but this isn't part of the earliest known versions.