Fishnets of the future may include musical tapes to lure the catch

The sound of sweet undersea music may send Scotland's economically hard-pressed fishermen waltzing back to port with record catches of ''captivated'' fish.

If Strauss's ''Blue Danube'' played on tapes lowered with fishing nets cannot tempt shoals of cod and haddock, the strains of Mozart might do the trick. Dr. Tony Hawkins, a researcher at Aberdeen's Marine Laboratory, has proved with tests at a Scottish Highlands loch that fish become curious and swim near nets when they hear pleasant music.

Apart from the use of taped music in deep-sea fishing off Scotland, melodious strains might be used by fish-farm owners who have long pioneered this activity in some west Scotland lakes, or lochs.

Academics have never been impressed with the theory that music can affect the behavior of fish, but Dr. Hawkins's experiments show that cod emit low-frequency grunts and haddock sound like motor bikes revving up when undersea loudspeakers play melodies.

Dr. Hawkins says cod have ultrasensitive hearing, three-dimensional sensitivity that protects them from predators below them while keeping them being acutely aware of overhead noise.

A researcher from the Dutch university at Utrecht is helping Dr. Hawkins with more musical surveys. With fierce competition continuing in the fishing industry , finding the right tunes for the right fish could be an interesting development for Scotland's dwindling number of fishermen.