Shoal owner

Fish ranching

source Geoff Watts
New Scientist July 28 2001
Starts p40, 4 pages long

Fish ranching is an idea proposed by University of Plymouth researcher, Jonathan Lovell. This is a different technique from fish farming, which may lead to pollution and disease, since the fish have less space. Ranching involves training fish to swim in a certain direction in response to a stimulus, and using food rewards. Lovell has carried out work in tanks using goldfish, carp, bass and mullet. He estimates that it takes two weeks to train fish, feeding them twice a day, and their ability to respond lasts for a minimum of four months.

Other work using conditioning techniques to train fish is being carried out by Jens Balchen in Trondheim, Norway, where researchers at the University of Science and Technology have been carrying out field trials. One use for conditioning is to store fish alive in a closed-off bay, when there are too many fish for a freezing plant to deal with. They can be recaptured later using conditioning.

There are legal issues that need to be tackled, if this technique is to become widespread, such as what to do about rustlers who use sound generators to catch fish fed by someone else.