Icelandic Food and Veterinary Authority investigates salmon farming practices to mitigate net damage

The Icelandic Food and Veterinary Authority is investigating potential improvements in salmon farming practices to reduce the risk of damage to nets and the escape of farmed fish. The focus is on practices and materials used by companies, particularly the steel hooks employed when lifting nets from the water.

Four types of nets are currently utilized in salmon farming, mainly made of HDPE plastic and nylon, with trials underway for ultra-strong materials like Dyneema. While nylon nets have not caused significant issues in Iceland, they have been damaged by seals in the Faroe Islands. Nylon is less robust than its counterparts but provides better elasticity, considering the fish’s wellbeing when interacting with the nets.

Karl Steinar Óskarsson, who oversees the aquaculture division at the Authority, has initiated a special study to determine what damages nets and causes accidental escapes. Companies are required to report any net damage, even if it involves a single mesh rupture. The continued collection of data this year aims to identify correlations between net handling practices and material deterioration.

MAST is examining all aspects of net handling, including maintenance, repair, and storage. Increased lifting of nets—for instance, when harvesting fish or treating them for lice—carries a higher risk of damage. Some operators hang nets using specific hooks to reduce strain, while others secure them to minimize any potential force that could tear a mesh.

The findings could form the basis for future regulations concerning material selection and operational protocols in salmon farming, with the hope of recognizing patterns that contribute to net damage.