The use of lumpfish in salmon farming

The Challenge

Every year 50 million lumpfish are needed by the Salmon aquaculture industry in Europe to eat a parasite called 'Sealice' off salmon. Sealice are external parasites that feed on the skin and mucus of the Atlantic salmon, they can reduce salmon growth, health, and welfare, causing multimillion-pound commercial losses to the industry globally. Research carried by the Centre for Sustainable Aquatic Research (CSAR) has made it possible to culture lumpfish in captivity. Lumpfish are an efficient cleaner fish that eat these parasites and can reduce the use of anti-sea lice drugs by 80%.  There is no vaccine against sea-lice infestation. Only a small number of anti-parasitic therapeutants are currently licensed for treatment, and these are losing their efficacy due to evolved parasite resistance.  Having lumpfish in the salmon cages eating the sea-lice is an attractive and environmentally friendly alternative.

The Method

CSAR has been working with salmon and lumpfish farmers since 2015 to sustainably farm lumpfish. We did a gap analyses and we found three challenges: 1) artificial breeding of lumpfish in captivity; 2) selection of the best individuals for sea-lice control and 3) ensuring better welfare of lumpfish. Together with industry partners, welfare organizations and post graduate students we tackled all three challenges:

1. To develop artificial breeding, we produced nine Standard Operation Procedures (SOPs) focusing on the screening of diseases, artificial fertilization, and husbandry. All are freely available to download.
2. We showed that some native lumpfish populations have traits that make them better suited for aquaculture and, that these should not be translocated while there is a risk of escapees.
3. We also developed, in collaboration with our commercial sponsors, the first Operational Welfare Score Index for lumpfish

The Impact

Sea lice control costs salmon farmers worldwide more than £700M p.a. and results in a 17% loss of growth and impaired welfare. Using cleaner fish is more cost-effective and less damaging than using anti-lice chemicals. For these reasons, the number of cleaner fish used by the salmon farming industry has increased exponentially since 2008 and amounted to 50 million in 2020 (+15 million in the UK alone), +64% of which are lumpfish. CSAR research facilitated the selection of locally adapted ‘elite’ lines of lumpfish better adapted to survive in captivity, created jobs, improved welfare standards, and played a key role in the economic regeneration of the finfish aquaculture industry in Wales.

We placed lumpfish welfare in the spotlight by organizing and hosting the First Symposium on Welfare in Aquaculture - Welfare Indicators for Novel Species (14th of May 2020) which was followed by the knowledge exchange workshop on lumpfish welfare. This event was reported by the FishSite and praised by the industry.

In 2020 we organized the Second Symposium on Welfare in Aquaculture: Operational Welfare Indicators for Fish. Over 260 participants from all continents attended this webinar.