A more nuanced view of fish welfare and stunning methods

Fish welfare is too important for oversimplification. This article offers a balanced perspective on stunning methods, backed by science and experience.

Kyst.no recently published an article based on a scientific opinion from the Norwegian Scientific Committee for Food and Environment (VKM), conducted on behalf of the Norwegian Food Safety Authority. The topic is important, and we welcome more attention to fish welfare. However, the article presents an oversimplified and, in some areas, misleading picture of the current reality, especially when it comes to electrical stunning. 

Electrical stunning is the most documented and scientifically verified method. 

Electrical stunning is likely the most thoroughly documented and scientifically validated method for the humane stunning of fish available today, as is confirmed in VKM’s assessment. 

Optimar’s electric stunning system is supported by five EEG studies on Atlantic salmon, in addition to four behavioral studies. EEG, which measures brain activity in real-time, is described by VKM as the most accurate method for confirming unconsciousness. These are not opinions – they are hard scientific data. 

In contrast, only two EEG studies exist for percussive (mechanical) stunning – one on Optimar’s percussion system and one on an older and less relevant system. Several of the studies cited in the article and the VKM report rely on equipment or methods that the Norwegian Food Safety Authority does not approve. Despite this, the article presents electrical and percussive stunning as equally validated methods of stunning. 

This kind of framing risks steering the debate in the wrong direction, and that’s serious because it undermines trust in the fish welfare work being done across the industry. 

You can’t compare what we know to what we don’t know. 

Bjørn Roth, a leading scientist at NOFIMA, explains that the article creates a false balance. While electrical stunning has been thoroughly researched, its strengths and limitations clearly identified, very little scientific work has been done on mechanical stunning. 

– As a scientist, it’s misleading to compare known weaknesses against undocumented potential strengths, Roth says.  

– For instance, the legal requirement for humane stunning is that unconsciousness must occur within 0.5 seconds, which has been demonstrated with electrical stunning. Percussive stunning, however, has been shown not to meet that threshold. From a scientific and regulatory standpoint, that makes percussive stunning unfit for use. EEG is a research tool. EEG is designed to answer questions about the fish’s state of consciousness that no other method can clarify – not to satisfy paperwork requirements, he says.  

It takes more than good intentions. 

Optimar has delivered electric stunning systems for over 15 years, both for bleeding vessels and land-based facilities. We are an active partner in FHF-funded R&D projects and a member of the Fish Welfare Platform, working systematically on continuous improvement and scientific validation. 

We take this seriously. Ensuring good fish welfare takes more than good intentions. It requires facts, experience, and tested technology. 

Doing what’s right – for the fish 

We fully agree with VKM’s conclusion: the industry needs more data and tighter standards. All methods must be held to the same requirements. That also means giving credit to the stunning methods that are already well-documented. 

Fish welfare is not a matter of opinion or tradition. It’s about using what is thoroughly tested, proven, and continuously improved. It’s about doing what’s right – for the fish. 

To succeed, we need the entire industry, wild catch, aquaculture, and regulatory bodies to work together. At Optimar, we are prepared to contribute the necessary equipment, systems, and personnel to support the development of solid scientific foundations for further evaluation in collaboration with research leaders such as IMR in Bergen, NOFIMA in Norway, and Wageningen University in the Netherlands. 

If we can achieve a joint initiative, it will lay a strong foundation for future regulations on the humane slaughter of fish and shellfish. We welcome the dialogue.