Aquaculture: Sea lice levels plummet as Ahousaht and Cermaq set a new standard

A 22-month farmed salmon production cycle with zero mechanical delousing treatments highlights how Indigenous stewardship and innovation is reshaping aquaculture in British Columbia.

By Fabian Dawson
SeaWestNews

The Ahousaht First Nation and Cermaq Canada have reached a historic milestone by completing a 22-month farmed salmon production cycle without mechanical sea lice treatments, demonstrating what Indigenous-led stewardship and modern aquaculture can achieve in British Columbia.

This success was achieved through years of collaboration and innovation focused on sea lice management in Ahousaht Territory, which hosts 12 active salmon farming sites on the west coast of Vancouver Island.

Sea lice are naturally occurring parasites found on many marine fish species in BC, including wild salmon. They do not pose a health risk to humans. Farm-raised salmon enter ocean pens free of sea lice but can acquire them from the marine environment, especially during wild salmon migration seasons when adult wild fish may pass sea lice to farm-raised salmon.

The Department of Fisheries and Oceans (DFO) regulates and audits sea lice levels on salmon farms, requiring routine monitoring and reporting throughout the year.

Salmon farming operations use several methods to control sea lice, including in-feed medicated treatments, mechanical removal using water jets, medicinal and non-medicinal bath treatments, barrier technologies, and timely harvesting when necessary.

In Cermaq Canada’s operations in Ahousaht Territory, no mechanical delousing treatments were used during the past production cycle, and only five in-feed treatments were given late in the cycle on a small number of sites. These measures meant the fish did not need to be handled for lice removal at any point.

In 2022, Cermaq Canada conducted 56 mechanical delousing treatments to maintain an annual lice level of 1.93 at its Ahousaht farms. Over the last 12 months, Cermaq has conducted zero treatments and maintained a lice level of 0.30.

Ahousaht’s Protocol Agreement with Cermaq Canada stipulates that sea lice levels must not exceed 1.5 motile lice during outmigration and 2.5 lice for the remainder of the year. These are more stringent than DFO regulations, which set a limit of 2.8 motile lice during outmigration.

The dramatic reduction in lice levels was achieved through closed containment pens and semi-closed containment systems, which limit the movement of sea lice between wild and farmed fish, combined with strict management practices and continuous monitoring, said David Kiemele, Managing Director of Cermaq Canada.

“As Cermaq completes its first production cycle with zero mechanical delousing treatments since the introduction of mechanical delousing in 2020, I am filled with resolve that when First Nations leadership is central to resource business decision-making, the result is beneficial to all involved — especially the long-term health and prosperity of our traditional waters,” said Ahousaht Hereditary Chief Richard George, Hasheukumiss.

In an interview with SeaWestNews, Kiemele credited the result to years of innovation and collaboration between the Cermaq team and the Maaqutusiis Hahoulthee Stewardship Society (MHSS), which leads the sustainable development of Ahousaht’s traditional territory in Clayoquot Sound.

“Six or seven years ago, we were facing significant challenges in our ability to proactively manage lice levels on our farms,” said Kiemele.

“We put a plan in place and worked diligently with the Ahousaht Nation. This milestone is the result of that time, energy, and focus paying off. It’s an example of an outcome-based management approach and of the First Nation and Cermaq working together to achieve this goal.”

As the federal government prepares a “Transition Plan’ to determine the future of salmon farming in British Columbia, Kiemele said the Ahousaht-Cermaq success offers a tangible model for sustainable aquaculture.

“It shows what can be achieved when science, technology, and Indigenous stewardship work hand-in-hand…but we need certainty and stability in government policy to build on this success,” he said.

Federal Fisheries Minister Joanne Thompson confirmed last week that the transition plan is in its final stages.
“I believe Canada can become a global leader in the next generation of aquaculture production,” she said.

Main image shows Ahousaht Hereditary Chief Richard George, Hasheukumiss.