Salmon Wars takes readers inside the globe-straddling salmon farming industry. The book investigates the health and environmental claims of the industry, separating marketing hype and dubious science from grim reality. The images here provide visual evidence of what really happens to the salmon and the environment when hundreds of thousands of these iconic fish are crammed into cages floating along fragile coastlines and critical migration routes for the declining numbers of wild salmon.

Above and Below

From above, open-net salmon farms appear benign. That’s the image the multinational salmon farmers promote. The truth is hidden below the calm surface of inlets, fjords, and coastlines, as seen in photos from Newfoundland and Norway.

What you don’t see is the excess feed, excrement, and harmful chemicals that collect below farms. The toxic stew can reach nearly three feet in depth and spread across the seabed, creating a dead zone that damages surrounding marine life. Two Canadian divers, Kathy and Dave Brush, were so shocked by what they found beneath a salmon farm that they brought a yardstick to illustrate the oozing pile.

This diagram, prepared by researcher Inka Milewski in 2021, details the waste production from an average salmon farm over a 22-month growing period. The estimated waste totals 879 metric tonnes, or nearly 2 million pounds, of excess feed, fecal material and nitrogen waste. The waste fouls the net pens and damages the seabed below.

Invisible from above, thousands of tiny parasites known as sea lice attack the caged salmon, eating their flesh, often killing them in huge numbers. The industry has spent hundreds of millions of dollars on increasingly powerful pesticides in unsuccessful efforts to eliminate the parasites. One result is the presence of chemical residue in the salmon.

Whom Can You Trust?

The industry, backed by some nutritionists, claims that farmed salmon should be eaten regularly as part of a healthy diet. Critics point to studies showing the presence of chemicals like PCBs pose health risks, particularly for infants, children, and pregnant women. One of the earliest studies of chemicals in farmed salmon can be found here. The industry’s campaign to discredit the Science magazine article was exposed by David Miller, a British academic, and his paper is found here. The effort to discredit critics is ongoing.

The industry says farmed Atlantic salmon are raised sustainably and naturally. Consumer groups filed three lawsuits in courts in the United States challenging those claims, highlighting assertions by Mowi ASA, the world’s largest salmon farmer, and its Ducktrap smoked salmon subsidiary. In 2021, Mowi, the world’s biggest salmon farmer, paid $1.3 million to settle the claims of false advertising.

The example of the deceptive advertising below came from court files. The judge’s order settling the main lawsuit can be found here.

Photos You Won’t See in Salmon Advertising

Joachim Drew, a scuba diver for salmon farms in Newfoundland, spent more than a decade diving inside cages at salmon farms that often were so clouded by chemicals, bacteria, and dead fish that he could not see the diver next to him. Part of his work entailed killing predators like tuna and sharks. Once he and his colleagues killed nineteen blue sharks in a single cage. In the photo below, Drew is repairing a huge hole in a net made by a predator. Drew’s YouTube channel may be found here.

Melvin Jackman lives beside a pristine cove on Hermitage Bay, a majestic body of water on the southern coast of Newfoundland. In recent years, the surrounding shoreline has become a waste dump for debris washing up from three farms in the bay operated by Cooke Aquaculture. He has spent years trying to get the Canadian government and Cooke to clean up places like the cove seen below.

While the industry boasts about its treatment of farmed salmon, a different perspective came from an undercover video by Animal Outlook, an animal rights group. In three months of undercover work at a Cooke Aquaculture salmon hatchery in Maine, investigator Erin Wing found numerous incidents – stomping on live fish or throwing others into barrels – that violated industry norms. The State of Maine took no action against the company.

The Disaster That Changed a State

In mid-August of 2017, an open-net salmon farm in Puget Sound broke apart, sending more than 250,000 alien Atlantic salmon into waters home to endangered Pacific salmon. An investigation by three Washington State agencies found Cooke Aquaculture, the owner of the farm, was negligent in cleaning its nets and maintaining the farm. The environmental disaster led to a ban on open-net salmon farms in the state’s waters. The report can be found here.

While tens of thousands of salmon escaped, others were trapped and died in clogged nets. When the nets were hauled out of the water, State investigators and a federal criminal investigation found that the nets had not been cleaned properly for months.

Farmed Salmon Die in Huge Numbers

Farmed salmon die at shocking rates from disease, parasites, predators, and warming oceans. In Norway, 52 million fish died before harvest in 2020. In Scotland, the mortality rate for farmed salmon quadrupled between 2002 and 2019, as the industry grew larger. Estimates are that 15 to 20 percent of all farmed salmon worldwide die each year before they can be harvested. By comparison, the mortality rate for chickens in 5 percent and 3.3 percent for cattle feedlots.

In one of the industry’s worst die-offs, an estimated three million salmon died at 10 farms off the Newfoundland coast at farms owned by a subsidiary of Mowi in the summer of 2019. The company blamed the incident on warming waters, a claim questioned by others. Here, the flesh of dead salmon was pumped into the water by a salvage vessel, coating the shoreline for miles.

Some scientists likened the salmon fat decomposing on shoreline to an oil spill.

The huge losses continue. In early 2022, Mowi reported that its Newfoundland subsidiary, Northern Harvest Sea Farms, lost 1.3 million salmon at its farms in the last four months of 2021; one site lost 80 percent of its 700,000 salmon. The company blamed “environmental challenges,” including an average of 14 sea lice on every single fish.

Saving the Wild Salmon

Wild Atlantic salmon were once so plentiful in the rivers of the Northeastern United States, eastern Canada, Europe, and Scandinavia that the supply seemed inexhaustible. Today, rivers that counted ten thousand salmon returning to spawn now find numbers in single digits. There are many causes, including the spread of disease and parasites from salmon farms to wild fish.

 The Atlantic Salmon Federation operates a station on the Magaguadavic River in New Brunswick to monitor returning wild salmon and escaped salmon from farms in the Bay of Fundy. Salmon climb the ladder below and are caught in a metal cage at the top.  In recent years, the number of wild salmon has decreased sharply and the number of escapees from farms has increased.

Below, ASF scientist Graham Chafe pulls a salmon from the metal cage at the top of the ladder to see whether it is wild or farmed. Farmed salmon are euthanized and sent to a nearby government lab to test for diseases and wild salmon are released to continue their journey upstream.

Chafe uses rings on a fish scale to differentiate farmed salmon from wild salmon at the ASF site. The almost-concentric rings here show a farmed salmon that was fed regularly; the rings are more varied on wild salmon to reflect irregular feeding and their long migratory journey across the Atlantic.

A fly fisher on the Miramichi River in New Brunswick, one of many rivers in eastern Canada and the New England that have seen the number of wild salmon drop to near-extinction levels. Efforts to restore the river have provided some hope, like efforts on the Penobscot River in Maine.

The Future of Salmon Farming

 Land-based salmon farms offer alternatives to raising salmon on the open ocean. This new technology relies on recirculating aquaculture systems, known as RAS, to raise fish in huge tanks on land. Because the fish are not exposed to outside viruses and parasites, the farms use far fewer chemicals and eliminate the threat to wild salmon from pathogens spread by open-net farms. RAS-based operations have sprung up in some unlikely places, like Switzerland, Japan, the United Arab Emirates, and just outside Miami, Florida.

 One of the pioneers was Sustainable Blue, a land-based salmon farm in Nova Scotia. The facility raises salmon in tanks free of chemicals that can harm humans and the environment and recycles its waste and water.

Atlantic Sapphire’s huge plant outside Miami is the world’s largest land-based salmon farm. Because of its scale, the success or failure of Atlantic Sapphire will affect the future of this disruptive new technology.

In rural Wisconsin, Superior Fresh uses a unique method that combines hydroponics and aquaculture to raise Atlantic salmon in freshwater and recycle 99.9 percent of the water to a 13-acre greenhouse where vegetables are grown. Salmon are born in freshwater rivers and streams, migrate to oceans to mature, and return to freshwater to spawn. By using methods that allow salmon to be raised only in freshwater, Superior Fresh opens to door to recycling the water for hydroponics and locating salmon farms any place there is a source of fresh water.