The Hidden Costs of Farmed Salmon
Salmon is one of the most popular seafoods worldwide, praised for its rich protein content and omega-3 fatty acids. It is often seen as a healthier alternative to meat or poultry. Yet, while salmon appears abundant on restaurant menus and in grocery stores, many wild salmon populations are in decline. Today, unless otherwise specified, most salmon comes from fish farms rather than the wild.
From Rivers to Cages
Wild Atlantic salmon once thrived across the North Atlantic, ranging from Portugal to Newfoundland, but they have disappeared from many waterways and are now at risk of extinction. Meanwhile, domesticated Atlantic salmon are increasingly farmed in offshore cages, especially in Norway, British Columbia, and Chile. In Chilean Patagonia, more than 1,500 salmon farms have applied for permits, sparking concerns about the region’s fragile marine ecosystems and growing eco-tourism economy.
Environmental and Ethical Concerns
- Pollution: Waste from salmon pens, including uneaten feed and fish excrement, collects on the seafloor and promotes algae growth. This can create oxygen-deprived dead zones, damaging surrounding ecosystems.
- Disease: Crowded pens are ideal breeding grounds for parasites and illnesses such as infectious salmon anemia. To combat outbreaks, farms often rely on pesticides and antibiotics, some of which are typically reserved for human use.
- Escapes: Millions of farmed salmon escape each year, where they compete with wild fish, spread disease, and disrupt natural ecosystems.
- Overfishing: Farmed salmon are carnivorous and rely on feed made from wild-caught fish such as anchoveta, sardines, and jack mackerel. In Chile, it can take up to eight kilograms of wild fish to produce one kilogram of farmed salmon, further straining global fish stocks.
- Artificial Colorants: Because farmed salmon’s diet lacks krill and other shellfish that give wild salmon their pink hue, farmers add colorants to make their flesh look “salmon-colored” instead of gray.
Searching for Sustainable Solutions
Not all aquaculture is harmful. Scientists in Puerto Rico and elsewhere are researching ways to improve salmon farming by studying environmental factors such as depth, currents, and farm placement to reduce pollution and disease risk. These efforts aim to make aquaculture more sustainable and lessen its impact on surrounding ecosystems.
A View from Patagonia
Visiting Puerto Natales in Chilean Patagonia reveals both the beauty and the tension of salmon farming. Against snow-capped peaks, salmon pens float quietly in the water. To the casual observer, the farms may seem harmless. Yet the introduction of thousands of non-native fish into pristine waters poses real risks to local biodiversity and tourism industries that depend on unspoiled environments.
Rethinking Salmon on Our Plates
Salmon remains a beloved food, but its story is more complicated than it seems. Eating farmed salmon means weighing its health benefits against environmental costs. The next time you order salmon, take a moment to consider its origin—and what impact that choice might carry for the oceans and communities that depend on them.
