He's eating his way through that line.
4 seconds sound clip from the Jaws (1975) movie soundboard.
You can hear this line at 01:43:47 in the Blu-ray version of the movie.
Quote context
[...]
- Stand away from those stern cleats!
- Back home we got a taxidermy man. He's going to have a heart attack when he sees what I brought him.
- Throttle back. You're losing a cleat.
- My God, this one, too. They're both going.
- He's eating his way through that line.
- Yeah. He's working his way right up to us.
- Quint! Come on, Quint. Hurry! Come on. Quint!
- Untie this. He'll pull out the transom.
[...]