Sea lice can be a big problem for some fish. Here’s how the ASC helps to ensure the problem is effectively managed

Sea lice are parasites that can affect the health and welfare of farmed fish, particularly salmon. These tiny crustaceans are naturally found on marine fish, and feed on the skin and blood of the fish.

Sea lice can be a problem for farms where salmon gather closely together in one location, making it easier for the lice to spread. There is also a risk that those lice could impact the health of wild salmon populations, if they are migrating nearby.

How we help

All of this makes the management of sea lice a critical factor of the ASC standard for responsible farming. This is an issue that is tackled by numerous requirements in the ASC Salmon Standard, and these requirements are currently being reviewed to ensure they are up to date.

ASC certified salmon farms must work with other farms (even if they are not ASC certified) in their area to create an Area Based Management plan to minimise the collective impact of the farms. No ASC farm can use chemical treatments that have been banned in any salmon producing country, and all chemical treatments must be signed off by a vet before use.  The ASC Salmon Standard also sets very strict limits on chemical treatments, requiring that farms use non-chemical treatments instead wherever possible, keep the number of chemical treatments below strict limits and ensure  any chemicals do not affect local biodiversity.

Is the industry taking this seriously?

It is also an issue that the wider industry is taking very seriously. All farmers have to deal with parasites and disease, but the aquaculture industry is an innovative industry and many new solutions are being trialled to deal with sea lice that don’t involve potentially harmful chemicals. just some examples currently being used or researched include thermal treatments; ‘snorkels’ that form a barrier against sea lice while allowing salmon to reach the surface of the water; and anti-sea lice feed. This is fast progress for an industry that is only a few decades old, but there is always more to be done, and ASC will continue to encourage farms to further reduce their use of chemicals.

The below video is from a series of documentary films by an independent Norwegian journalist and part-time angler who asked Greig Seafood how they tackle the sea lice issue.



Can more be done?

At ASC we share people’s concerns about the impact of sea lice on farmed salmon, which is why are reviewing our requirements on this area. The ASC Salmon Standard already includes requirements limiting the number of sea lice that present during sensitive periods for any nearby wild salmon populations, but this review will look at the latest evidence to see if these requirements can be further strengthened.

We have also commissioned research in British Columbia to better inform the sea lice debate. This research will dive into data from BC farms to provide in-depth insights into sea lice levels throughout the year, how and when these numbers go up, as well as what effect different treatments have. The data will come from multiple sources, including ASC certified farms which must publish such data as a requirement of certification. This will be used to inform the review of our standard, but we envisage it also having wider implications to others in the industry.

Support responsible farmers: Look for the logo!

If, like us, you want to only shop and eat seafood products that have been produced with care by responsible farmers, simply look out for the ASC logo when you shop and eat out. And if it’s not there – ask why not!

Aquaculture explained

Confidental Infomation