Saving Seafood

Sea lice impact from salmon farms on wild salmon are overestimated: study

August 16, 2024 — A study, published in Reviews in Aquaculture journal, has identified that the effects of sea lice from salmon farms on wild Atlantic salmon have been overestimated.

The study reviewed the Norwegian regulatory management of the salmon farming sector and concluded that sea lice infections on farms are not associated with a measurable impact on wild salmon. Sea lice are marine parasites naturally occurring in the ocean and have co-existed with wild salmon for millions of years. Farm-raised salmon enter the ocean free of sea lice, a press release from B.C. Salmon Farmers Association states.

“This is an important finding, as it aligns with the research and data we are seeing on sea lice in Canada,” said Simon Jones, research scientist at Fisheries and Oceans Canada (DFO) and co-author of the published review. “The highly variable relationship between lice levels on wild salmon and salmon aquaculture in B.C. indicates the need for a greater understanding of all factors affecting the survival of wild salmon.”

Read the full article at Aquaculture North America

PBS Newshour Highlights Innovations, Challenges in Salmon Farming Industry

August 29, 2022 — Last week, the PBS Newshour featured a segment on salmon farming, addressing the challenges and innovations that have accompanied the industry’s growth. Newshour science correspondent Miles O’Brien talked to salmon farming industry members about the state of the industry and improvements being implemented. As demand for seafood increases each year, aquaculture is likely to play a major role in keeping Americans well-fed and healthy.

Below is an excerpt from the transcript of the segment. Watch the full video here.

Miles O’Brien:

Off of Swan’s Island, we boarded the ship where they monitor and feed their crop of nearly a half-million salmon. They’re kept in 16 flexible floating nets made with stainless steel fiber to guard against escapes.

We watched as they fed some of the fish using a network of submerged cameras.

Andrew Lively, Cooke Aquaculture:

He’s seeing the fish, and there’s no feed coming down through the water column.

 Miles O’Brien:

The trick is releasing the feed at just the right rate. Too fast, and it falls to the bottom of the sea, impacting the bottom line. But it also can cause an environmental problem. As the feed decomposes, it generates nitrogen, as does the fish poop.

High nitrogen levels are a persistent problem for salmon farmers.

Do you feel like you have met those challenges?

Andrew Lively:

One of the big ways to deal with that challenge is proper site location and proper density. We’re in an area that gets about a 12-foot rise and fall of water twice a day, so lots of current, lots of freshwater going through here.

 Miles O’Brien:

Even at the perfect location, fish farmers must closely monitor a myriad of factors to keep their crops healthy. 

Farmed salmon are frequently beset with serious infestations of sea lice. To combat the problem, Cooke deploys custom designed boats equipped with warm freshwater showers to clean the fish. It’s an expensive solution that might soon have an unlikely replacement.

Marine biologist Steve Eddy is director of the Center for Cooperative Aquaculture Research at the University of Maine.

These fish are lumpfish. Tell me about them.

 Steve Eddy:

So these are used as a cleaner fish to remove sea lice off of farmed salmon, a form of biological control.

 Miles O’Brien:

Researchers here believe one or two lumpfish per 10 salmon in a pen should be enough to delouse the whole school.

It takes about three years for a salmon to grow from egg to market. As complex and resource-intensive as aquaculture is, its sustainability compares favorably to some land-based agriculture.

Read the full transcript at PBS Newshour

Conservation group sues to stop commercial salmon farms

November, 5, 2015 — SEATTLE (AP) — The Wild Fish Conservancy filed a lawsuit Wednesday against federal environmental and fisheries managers for allowing commercial salmon farms in Puget Sound.

The lawsuit filed in U.S. District Court in Seattle says that infectious viruses in salmon farms are threatening wild fish in the region.

The National Marine Fisheries Service and U.S. Environmental Protection Agency concluded in 2011 that commercial salmon farms are not likely to have an adverse effect on wild salmon, the lawsuit said.

But the following year, it said, there was an outbreak of an infectious virus at a commercial salmon farm at the south end of Bainbridge Island in Puget Sound. The outbreak occurred while wild juvenile salmon were migrating through the area and likely had a significant impact on the wild fish, the group said.

The lawsuit seeks an injunction that would force federal officials to reconsider commercial salmon farms in Puget Sound in light of the outbreak.

Read the full story from the Associated Press at the Connecticut Post