Waste Management

Aquaculture operators have a vested interest in minimizing waste

Over the past 15 years, aquaculture management practices and technologies have matured and improved to reduce waste.

Waste such as feces and uneaten food can fall to the sea bottom and decompose causing localized oxygen reduction and other chemical changes in bottom sediments.

Today, several federal and provincial regulations are in place to ensure the waste from fish farms is limited to a small area directly under the farm and immediately surrounding waters. As well, fallowing requirements ensure that the seabed is allowed time to recover between production cycles.  The new British Columbia marine salmon aquaculture licences being issued under the Fisheries Act provides an example of such control measures.

Aquaculture operators have an incentive to support and comply with such measures as they need a healthy ecosystem in which to grow their stocks.  They are also driven to be economically efficient in their operations as uneaten or wasted feed is very costly to the companies and affects their bottom line

Reducing waste - a step towards sustainability

Key methods of reducing waste include:

Reducing the amount of uneaten feed
The high cost of feed has pushed aquaculture operators to greatly reduce any waste. Farmed fish can convert food to flesh very well, and today’s feed is easier to digest. Underwater video cameras are used, particularly for salmon farming, to ensure that waste and the amount of uneaten food reaching the bottom are minimal.

Removing mortalities quickly
As with other livestock, stock mortalities do occur on farms. For disease control and predator avoidance reasons it is important that these fish are removed quickly. Farmers may have built in mechanisms to remove the mortalities from the nets or they may use divers.  These mortalities can often be used for fertilizer or composting.

Key legislation used to regulate waste management:

Provincial, territorial and federal legislation is used to regulate waste management. Provincial regulations require fish farmers to record conditions of the seabed before the production cycle begins and to monitor any changes during production. Fisheries and Oceans Canada uses the Fisheries Act to regulate any effects on habitat.

• Fisheries Act
• Provincial & Territorial Regulations

Regular monitoring

Fisheries and Oceans Canada and other federal, provincial and territorial governments regularly monitor aquaculture sites to ensure they are operating responsibly and minimizing waste:

• Monitoring of the data aquaculture operators must provide as requirements of their licenses
• Conducting periodic on-site audits of operations

Learn more:

• Fact Sheet – Waste Management
• Fisheries Act
• Canadian Environmental Assessment Act