Farmed Salmon vs. Wild Salmon

Do you eat salmon? If so, how do you like it? Do you barbeque it? Do you have it as sushi? Do you steam it with veggies?

If you’ve ever bought salmon from the grocery store, you might have noticed all kinds of information on the packaging. You might have seen the type of fish as Pacific or Atlantic salmon. Or you might notice it is labelled “farmed” or ''wild.” What does it even mean to farm fish? How does farming fish compare with farming other livestock on land? It is important to ask questions like this because the way that food is produced can affect the environment and our health.

Did you know?

Farming fish and other species that live in water is known asaquaculture.aquaculture.

Let’s learn about what a fish farmfish farm is. Then, we’ll discover some of the benefits fish farming can bring and some of the challenges. Finally, we’ll look at how to farm fish sustainably.

What does “farming” fish mean?

A fish farmfish farm, also known as an aquaculture facility, is a large water-filled enclosure that humans control. In Canada, salmon farming typically either takes place in net pensnet pens in the ocean or tanks on land. 

Net pens are cage-like structures made out of nets. They are located in open bodies of water, such as the ocean. There are different types of net pens based on their distance from the shore. Coastal or inshore net pens are located near the coast. Ocean or offshore net pens are located far from the coast. 

Raising fish on land in tanks is known as land-based aquaculture. This is a lot like raising fish in swimming pools. 

What are some of the challenges with farming salmon?

Farming salmon can produce millions of salmon that are used for food. But some people have concerns with farming practices.

Net pens can house thousands of salmon in a fairly small area. This means that the salmon live in a small space compared to in the wild. How small is small? In general, salmon farms keep the populationpopulation density around 15 kg/m3. This is about the same as two adult salmon per cubic meter. 

The density of populations is carefully studied to make sure that the fish have space to swim freely. People working with the fish also make sure that there is enough dissolved oxygen in the water for the fish to survive and do well. They also make sure that the fish and water quality are continuously monitored. Fish behaviour is also monitored to spot any sign of disease or distress.

However, when fish are close together, it is easier for parasites such as sea lice to spread among them. In the past, chemicals were used to treat lice. This can be harmful, especially for young fish. AquaculturistsAquaculturists now use cleaner fish to control the sea lice.

New technologies are also being studied to control sea lice in innovative ways. One example is putting the net pens in deeper waters, where the temperatures too low for sea lice development. New approaches such as these are good examples of methods that make aquaculture sustainablesustainable.

Concerns have also been raised that fish farms produce waste such as fecalfecalmatter, uneaten food, and chemicals. This waste can concentrate under pens in shallow water and can affect the environment, including nearby wildlife. To address this concern, modern salmon farms are located in deeper water. This allows them to take advantage of the rising and falling tides. The tides create currents which transport wastes out to sea. In addition, aquaculturists use underwater cameras to monitor feeding. This helps cut down on food waste.

Did you know?

Careers in aquaculture include business managers, research scientists, technicians, policy advisors, scuba divers, waste management specialists, and many more!

There can also be problems if salmon escape from the net pens. Escaped fish compete for food with local wild fish. If the farmed fish have parasites or other diseases, they can spread to healthy wild fish populations.

Scientists are studying how escaped farm fish can survive in the wild. For example, they are looking into the impacts of when farmed salmon breed with wild salmon. They wonder if farmed salmon are as capable of surviving in the wild as wild salmon. More research needs to be done on this to find out if this is the case.

Salmon Farming and Human Health

Health professionals often recommend eating salmon instead of red meat, such as beef. They say salmon is healthier. But some people have concerns about eating farmed salmon. They believe that farmed salmon are less nutritious. This is not true. Farmed salmon are fed diets which are very similar to what they would eat in the wild. These diets are high in fatsfats and proteinsproteins . Studies about wild and fresh salmon have found that both are equally nutritious.

The meat of both farmed salmon and wild salmon, like most foods we eat, contains traces of harmful compounds such as polychlorinated biphenyls (PCBs). However, the levels in both farmed and wild salmon are well within the levels that are considered safe to eat. In fact, health authorities suggest eating oily fish like salmon several times per week as part of a healthy diet. This is because salmon, including farmed salmon, are excellent sources of omega-3 fatty acidfatty acid, as well as vitaminsvitamins such as vitamin D, and calciumcalcium.

Did you know?

By 2030, two thirds of the world’s fish is expected to come from aquaculture.

Salmon Farming in Canada

The Government of Canada reports that an average of 122 300 tonnes of farmed salmon was produced from 2011 to 2015. British Columbia produced 60% of this. Other important salmon-producers include Newfoundland and Labrador and New Brunswick.

However, aquaculture is more than fish farming. Many mollusksmollusks are produced commercially in Canada, as you can see in the diagram below.

How can we farm fish sustainably?

How can we keep farming fish while making sure we have the least impact on the environment? In other words, how can we have sustainablesustainable aquaculture? Scientists and fish farming companies around the world have been working tirelessly to find solutions. In Canada, the aquaculture industry has already made significant changes to address health and environmental concerns. In addition, they continue to conduct research and respond to the public’s concerns.

Did you know?

Scientists studying the environmental impacts of meat production found that cattle can produce about 20 times more greenhouse gases than farmed salmon. This difference does not apply to all types of aquaculture. Farming catfish had the same impacts as farming beef. 

One way to make salmon farming more sustainable is to do more land-based aquaculture. This form of fish farming is seen as less threatening to sea life than ocean or coastal net pens. But it can be more expensive to do.

For example, a recirculating aquaculture system is essentially a large, complicated aquarium. 

These systems come with some costs that net pens don’t. For example, they need heating, electricity, and lots of human staff. This increases their carbon footprint.carbon footprint. Another concern of land-based aquaculture relates to the treatment of the fish. Because environmental conditions can be closely controlled, the population density of fish can be much higher. This can result in very cramped conditions. Current land-based systems often have population densities closer to 100 kg/m3 as compared to 15 kg/m3 in net pens. It has also been noted that land-based aquaculture uses a lot of freshwater. This might take water away from local plants, animals and people.

Another possibility being investigated is to grow fish in giant offshore aquapods. An aquapodaquapod  is a large, spherical cage that is suspended in the ocean. Aquapods can also be free-floating. The pods are connected to a boat with workers and a supply of food for the fish. The thinking is that, since aquapod systems are further removed from the coastline, they are exposed to wind, waves and ocean currents. As a result, any wastes produced will fall into deeper water or be more spread out. Since the free-floating aquapods drift on the ocean currents, they would always be moving to new stretches of ocean.

The Future of Fish on Your Plate

Regardless of whether it is carried out on land or in the sea, food production systems can potentially harm the environment if not done properly. This is why these concerns are addressed by scientific research, governments, and industry. With years of experience and research, sustainable aquaculture is now a reality. Taking better care of the fish today will enable us to take better care of ourselves tomorrow.

It is in everyone’s best interest that we work to produce the best aquaculture products in Canada. This industry is important because it offers sustainable food products for your table. It has also allowed fishing communities to survive as net-based commercial fishing became impossible. Today there are almost 60 million people working in the aquaculture industry around the world, and that number will continue to grow.

According to the United Nations, fish are an important source of protein, vitamins, and minerals for people worldwide. Farmed fish have the potential to feed billions of people. After all, the world’s population is growing. Fishing in the wild can’t keep up with the demand of feeding all these people! Eventually, fish farming might be our only option. That’s why it’s important to do it sustainably.

How can you choose better options when buying groceries? Look for products with certifications from sustainable fisheries organizations. These certification logos identify the companies who follow best practices for our health and the environment.