Aquaculture: Salmon Farmers Slash Antibiotic, Sea Lice Treatment Use

New audited data from 11 global producers shows the salmon farming industry’s steep declines in the use of antibiotics and medication to treat sea lice.

By Fabian Dawson
SeaWestNews

The Global Salmon Initiative (GSI), a coalition of the world’s largest farmed salmon producers, has released its 2025 Sustainability Report, showing continued declines in antibiotic use and chemical sea lice treatments across member operations.

The report, published annually since 2013, is built on independently audited data from 11 member companies operating across Australia, Canada, Chile and Norway and collectively represents about 40 percent of global farmed salmon production.

It tracks 20 sustainability indicators per company, per region, split across 15 environmental measures and five social measures, covering everything from fish escapes and mortality to occupational health and safety and community engagement.

“There is no hiding from the data,” said Sophie Ryan, CEO of GSI. “Every metric in this report  from feed sourcing to antibiotic use, to how many people we employ exists so we can see clearly where we’ve made progress and where we still have work to do.”

“This year’s new and expanded metrics give us, and our stakeholders, a more complete picture of how our members are performing and where our collective efforts are driving improvements, and that’s the kind of data-driven progress GSI was built to deliver.”

The headline findings center on medication use. GSI reports a 68 percent reduction in average antibiotic use for salmonids across member companies since 2013, including a 22 percent decline in just the past five years.

Chemical treatment for sea lice, one of the industry’s most persistent environmental challenges, fell even further, with average combined medicinal sea lice treatments down 79 percent since 2013 and 63 percent over the last five years alone.

The report attributes the trend to improved vaccines, veterinary practices, and a shift toward non-medicinal sea lice management, a category GSI began tracking more closely this year.

Feed composition remains a central focus of the report. GSI members reported a 64 percent reduction in average fish meal use and a 31 percent reduction in average fish oil use since 2013, reflecting a broader industry shift away from wild-caught marine ingredients.

Sixty-five percent of member companies’ average production now carries Aquaculture Stewardship Council (ASC) certification, the report states. On the social side, GSI reports that member companies collectively employ more than 21,600 people worldwide.

GSI’s report positions farmed salmon broadly as “one of the most eco-efficient animal proteins,” citing its nutritional profile, including being high in omega-3 fatty acids (EPA and DHA) and vitamins D, B12 and B6, as part of the case for its role in sustainable food systems.

Main file image shows Sophie Ryan, CEO of GSI