Teaching cod good eating habits

NORWAY - Many hours patiently training cod produces results. Scientist Frank Kristiansen has taught wild-caught cod that dry feed is good food - and these cod have doubled their weight in three months.

Wild-caught cod are not very interested in dry feed. However, with small portions of feed and a gradual introduction Frank Kristiansen is teaching the fish to eat.

It is currently difficult to receive continual supply of cod because of seasonal fluctuations in the fisheries.

However, by taking fish ashore and feeding them like other farmed fish, it is possible to offer consumers cod year-round.

Fussy cod

However, experiences show wild-caught cod are fussy about what they eat. While salmon eat large portions of dry feed, only about 20 percent of wild cod which without problems accepts prepared feed.

Trials now show cod can be trained to eat dry feed. By soaking dry feed in fresh water, the pellet becomes soft and more appetising.

Kristiansen has seen that the cod gradually eat more and more after starting with just a few pellets. After a while, the fish becomes accustomed to the taste and consistency.

"It's quite natural that the cod don't want dry pellets. Small, hard brown pellets sinking down in the water don't awaken the cod's hunting and food instinct. They are used to eating fish and crustaceans," says Kristiansen, who is collaborating with the industry in Båtsfjord about the project.

Getting new habits

The trial results show that more than half the cod become used to the dry feed. The fish doubled their weight in the space of three months.

Kristiansen believes it is possible to get all the fish to eat.

"As a rule, the biggest ones and the fastest learners dominate and take most of the food. Therefore, it will be an advantage to sort the fish by size to start the feeding and during the feeding process."

Dry feed is good economics

Herring and capelin have normally been used as feed to date, but dry feed is far better economically. Producing one kilo of cod requires five to seven kilos of capelin or three to four kilos of herring. However, just one and a half kilos of dry feed is required per kilo of cod.

"Dry feed offers other advantages like longer lasting qualities and avoiding the costs for freezing which herring and capelin incur."

This is a collaboration project between Fiskeriforskning and fishing industry firms Aker Seafoods, Båtsfjordbruket and Skrovnes AS.

Ellen Hardy

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