Get the Facts

The term Aquaculture is a broad term referring to the farming of aquatic organisms like fish, shellfish, and seaweed in controlled environments for food, restoration, or commercial use. It ranges from small-scale operations to industrial fish farming and can be based in fresh or salt water or on land. It can be divided into two types:

Restorative Aquaculture: Small-scale farming of seaweed, kelp, and bivalves like mussels, clams, and oysters can be sustainable and restorative.

Extractive Aquaculture: Industrial open-net farming of carnivorous fish – such as salmon, sea bass, and sea bream – is a method of aquaculture where fish are raised in large, floating nets or cages in natural water bodies, often very close to coastlines. This method raises environmental concerns about resource depletion, the destruction of sea grasses and seabeds under the farms, plastics pollution, the use of high volumes of forage fish to feed smaller volumes of farmed fish, the spread of diseases, and escapes of farmed fish into the wild. The following facts offer additional insights into the consequences of this sector of aquaculture.

Up to 20% of wild fish are used as feed to produce a much smaller quantity of farmed fish,

These operations, which not only take fish from food-insecure regions, also cause pollution and job losses in communities in which fish meal and fish oil processing factories are located.

Industrial-scale carnivorous fish farms are environmentally destructive

polluting coastal waters with excess organic and fecal matter, carbon dioxide, nitrogen and phosphorus. These pollutants collectively promote harmful algal blooms that can deprive the water of oxygen and destroy seabeds.

Carnivorous fish farms also pose a critical threat to Posidonia meadows

often referred to as the “lungs of the Mediterranean”, as their long leaves are known to produce large amounts of oxygen, while absorbing CO2. A hectare of Posidonia can store 15 times more carbon than a hectare of Amazon rainforest.

There has been increasing frequency and scale of mass mortality events

among farmed salmon since 2012, particularly in Norway, Canada, and UK. A total of 865 million salmon died in the ten years between 2012-2022.

Formaldehyde

is used by fish farmers to control fungus, parasites and diseases that affect salmon, despite its classification as a carcinogen. Other pesticides used include azamethiphos, a chemical known to kill marine wildlife, and emamectin, which poses a danger to crabs, lobsters and other crustaceans.

Carnivorous fish farms leave large amounts of microplastics and other debris in the water.

One study of 36 active sites and 5 abandoned sites in Greece revealed that all of the abandoned sites left behind a “very high burden” of abandoned infrastructure, equipment, and other litter while 56% of the active farms had broken buoys and floats with exposed and leaking Styrofoam.

Overuse of antibiotics

in the rapidly expanding aquaculture industry contribute to the rise of antimicrobial resistance, carrying potential consequences for animal-, human-, and ecosystem-health.

Marine ecosystems are turned into dead zones

from the immense amounts of excess fish feed and fish feces sinking to the sea floor.