Mari Lie Larsen, former researcher at the Fridtjof Nansen Institute (FNI), has successfully defended her PhD at the University of Bergen on March 21, 2025.  – and with great success!

Her dissertation, written at FNI, explores salmon aquaculture and management, focusing on how regulations and policies affect wild salmon populations. Titled "Evidence-based policymaking: Exploring the effectiveness of salmon aquaculture management in Norway", Larsen examines whether current management systems effectively control salmon lice and protect wild salmon stocks.

Despite increasingly strict regulations, wild salmon numbers continue to decline, and there are fewer wild salmon in Norwegian rivers than ever before. Larsen’s research shows that the knowledge base on the impact of salmon lice on wild salmon is based on a limited number of studies, often with methodological weaknesses. This could mean that the actual effects of lice have been underestimated.

Her findings also highlight weaknesses in the current management system. She suggests that area-based "emission limits" for salmon lice could be a more effective measure than existing regulations.

Among her opponents was Crawford Revie, Professor of Data Analytics at the University of Strathclyde and one of the most respected researchers in the field. He took great interest in Larsen’s work, emphasizing that the issue is just as relevant in Scotland and Canada as in Norway. He praised her for making a significant contribution to the international debate, and the audience followed an engaging discussion between them.

Kirstin Eliasen, head of salmon lice management in the Faroe Islands (Fiskaaling), also acknowledged the importance of her research.

The atmosphere throughout the defense was positive, with critical questions framed by curiosity and a genuine interest in understanding more about the research process.

FNI and the Greenlight project funded large parts of Larsen’s PhD work.

We congratulate Mari Lie Larsen on her PhD and look forward to following her work in the future!