How can the aquaculture industry best facilitate the lumpfish in the cages?

• The findings can contribute to a better facilitation of kelp hides and increase the quality of life for the cleanerfish.
• In recent years, the aquaculture industry has opened its doors to the use of lumpfish as a controlling measure against salmon lice. Today it’s estimated that the mortality of cleanerfish is higher than in other farmed species.
• One of the measures that can be put in to practice to improve the well being of the lumpfish is to optimize the kelps so that it can rest better. The artificial hides are therefore a necessity for the cleanerfish to get rest.

Testing of different kelps:

On behalf of NorseAqua AS, Aqua Kompetanse tested different types of kelps to see if the lumpfish preferred one type over another. The trial was conducted in two cages at the Kråkholmen site at Bjørøya AS in Flatanger, Trøndelag from November 2018 to March 2019. The hypothesis in the study was that thicker plastic types (HDPVC) gave a stiffer structure under water than thinner plastic types (PE), which would be easier for the lumpfish to rest securely on.

The results showed that lumpfish used the kelps with the thickest plastic (HDPVC), and especially the thicker plastic with the cork in the surface. The difference between the number of lumpfish that rested in thicker kelps was significant compared to thinner kelps, says Staven and Bendiksen.

 

Link to Norwegian article at Kyst.no: https://www.kyst.no/article/rognkjeks-foretrekker-tykk-tare/

 

 

For more information, you could read the magazine: Norskfiskeoppdret published the 8th of August 2019. Pages 106-111.