Shellfish and Sustainability

Shellfish aquaculture is the oldest form of aquaculture in Canada, dating back to the 1800s. The group of shellfish species grown in Canada is known as molluscs. Molluscs are filter feeders that literally clean the waters they live in, removing algae and sediments and providing very beneficial effects to their ecosystems. They also remove carbon dioxide from the ocean, thus helping to reduce greenhouse gases.

The recycling effect of filter feeding has also been shown to increase the productivity of sea-grass beds, important habitats for juvenile fish. The filter-feeding capacity of mussels is also essential for integrated multi-trophic aquaculture (IMTA). Mussel lines and oyster rafts provide habitat for a variety of invertebrates and fish communities.

Farmed shellfish rely on natural food particles present in the water column. They do not need to be fed. Growers are constantly monitoring water quality, according to standards set in the Canadian Shellfish Sanitation Program, and if there are problems, areas are closed and harvesting stops.

Shellfish are cultured in an environmentally sustainable manner. Mussels are grown in socks on ropes suspended in the water. Scallops are usually grown out in enclosed cages. Oysters and clams are seeded onto beaches or grown out on rafts. In every case, they are grown and harvested in a way that does not require dredging or disturbance of the ocean floor.

Learn more about shellfish and sustainability

• Canadian Shellfish Sanitation Program
• Shellfish Species
• Integrated Multi-Trophic Aquaculture