Sustainable fish feed: could Aquaculture be too good to be true?

words Irene Lodigiani

Fish-feed companies, LS Aqua and Boomer, are doing their best to reduce their impact but the key issues of waste and antibiotic contamination must be addressed

Environmental issues in aquaculture

Fish farming, similarly to animal farming, comes in many different shapes and sizes and it is impossible to make sweeping assumptions without first considering their differences. Fish can be reared on land in large tanks or in their natural environment, and aquaculture enterprises can have varying levels of impact on the surrounding ecosystems depending on their structure.

Fish-farms tend to have three main environmental costs. The first issue is the widespread use of antibiotics: the higher the density of the farm, the more antibiotics will be administered due to the spreading of illnesses in crowded conditions. Because in many cases semi-intensive and intensive fish-farms are located within larger bodies of water, the antibiotics run-off into the surrounding ecosystem, favoring the proliferation of antibiotic-resistant bacteria and the spreading of diseases to wild fish populations. Not to mention the health implications for human consumers who eat heavily medicated animals, favoring the presence of antibiotic-resistant bacteria in humans as well.

Initiatives on land have the chance to circulate waste-water disposing

High densities of fish also produce a high density of waste, which is a less talked about issue with aquaculture. While initiatives on land have the chance to circulate waste-water disposing of it correctly, farms of species located in sea, lake, or river pens do not, and the waste sinks below the cadges. As it drops to the floor, it causes changes in the seabed rendering the habitat inhospitable for wild species by modifying the levels of sediment. This creates dead zones which can range for kilometers and negatively impacts the ecosystem, as it impedes the reproduction of local species

The final issue with aquaculture is that the most popular species of fish, like salmon or tuna, are carnivorous, which means that they consume other fish to survive. As a consequence, these species have hidden environmental costs, as they must be fed high quantities of wild-caught fish to produce a single farmed counterpart making aquaculture an almost pointless effort.

Innovation in the fish farming field: the case of Biomar and LS Aqua

In a study by Fish In Fish Out (FIFO) in 2000, it took 2.57kg of wild fish to produce 1kg of farmed salmon, while in 2015 it took 0.82kg displaying an improvement in efficiency in the fish-feed industry. This jump forward is mainly due to innovation by companies such as Biomar and LS Aqua, who have been researching ways to minimize the dependency of aquaculture on wild-caught fish.

Biomar is a Danish company which specializes in the creation of fish-feed and in 2019 achieved the highest-ranking feed supplier in the Seafood Stewardship Index. Katherine Bryar, the global head of marketing tells Lampoon about the company’s ethics and aims: «Fish-farming is difficult because fish eat fish: Biomar’s objective was that if aquaculture was to expand to meet fish-consumption demands, then it needed to change their diets, making them less dependent on wild fish».

Biomar and LS Aqua fish-feed production

Biomar produces fish-feed for a variety of species from trout to sturgeon, and is one of the world’s leading manufacturers of pellets for farmed salmon. In 2019, sixty-two percent of fish feed produced by the company was used for salmon, but being a carnivorous species, it is hard to completely replace fish products in their diet. «Each year salmon feed gets more efficient, and the majority of their diet is protein and oils. The protein comes from soybeans, fava beans, lupin and a whole range of different ingredients meant to replace fish meal. Today, only twenty percent of salmon diet is made up of fish protein and of that twenty percent one third is made with off-cuts from making fillets and leftover fish from the industry, while the rest is from wild-fish capture. Of course, the wild caught fish are small species that people do not necessarily eat».

LS Aqua

LS Aqua is a Belgian company and is an established aquafeed innovator. Similarly to Biomar, they are experimenting in ingredients that can make fish-feed less dependent on wild-caught species and have made some discoveries. Paula Sole-Jimenz, the business development manager tells Lampoon: «We have been experimenting with micro-algae, insects and processed animal proteins, left-over pieces of meat from the slaughterhouse, blood, feathers, bone, excess meat which are ground up and reutilized. For shrimp we have reached a 100% replacement of fish-meal, but with fish we have only reached a fifty percent replacement. This is because in general with fish when you eliminate fishmeal there are health risks: they suffer from inflammation and are often underweight».

The issues of creating sustainable substitutes for fish-feed

To complicate matters further, different countries have different legislations, which means that animal protein use is restricted. For example, SUSPRO is a form of shrimp feed created by LS Aqua which does not use fish derivates, but is highly dependent on animal products: «SUSPRO was created three years ago and is a blend of different sources, mostly processed animal proteins, soy and other vegetables, but there are complications. In Europe mainly pig and poultry products are used but not ruminants because it is forbidden. We do not work so much in the EU because they have more stringent requirements. Our targets are Asia, Indonesia and Africa. We would also like to expand to Central and South America because they produce a lot of shrimp there. In Europe since 2013 aquaculture can legally use PAP’s but they are negatively perceived in Germany and France as they are trying to reduce meat consumption. Also, you have to be careful of religion when selling to foreign countries as Muslims do not accept pig side-cuts, which is why we mainly use poultry».

Problems in the experimentation with animal products in fish feed

Biomar has also encountered problems in their experimentation with animal products in fish feed: «We sometimes use animal products for feed. In Australia we use chicken bi-product, but not in the EU. Some countries have a history with animal products use- mad cow disease for example. If we use animal products it has to be safe, both for fish and human health». Insects are often perceived as a viable substitute for fish and animal products in aquaculture pellets, however this solution has a different set of issues Biomar explains: «Insects can be a source of protein, but they cannot replace fish oil. Insects are usually used to replace fish meal – we have carried out tests with soldier flies and earthworms as these are highly digestible and nutrient: any species of fish that needs protein can take insects. The problem is that the sustainability rating is not great at the moment because in Europe when you are growing insects you need to feed them human-quality food. If insects could be fed waste products, this would surmount the problem, but in the EU the law at the moment is that they can only be fed on human food. As a company we try not to problem shift here, so using insects solves one issue, but creates another. We need to change legislation to have food scraps as a legal source of food for insects so we could then scale up their production making it sustainable. We could then replace fish meal with insect meal».

Are viable solutions to fish feed enough?

Both Biomar and LS Aqua are doing their part in making aquaculture more sustainable. LS Aqua has created a shrimp-feed which does not depend on while caught fish and Biomar has reduced the percentage of fish in salmon feed to twenty percent of the total. These initiatives only partially solve the problem though. Modification of the pellets fed to farmed marine organisms can lessen the dependency on wild-caught species but it can do little to minimize the impact of aquaculture on the surrounding ecosystems as a whole, due to waste and antibiotic run-off.

Shrimp aquaculture is for the most part carried out overseas in countries like China, Indonesia and India and is cause for mangrove destruction, pollution and general health concerns. Shrimp produced in the global south is exported abroad offering lucrative monetary returns, while at the same time wreaking environmental destruction in the localities it is produced in. Salmon farming is causing sea-lice infestations in the surrounding water bodies and requires the use of heavy and constant medication. Despite this, a 2019 study found that 13.5% of farmed salmon dies prematurely due to health complications. Salmon waste is also creating dead zones and algal blooms in the areas surrounding their sea-pens which has led Argentina to become the first country in the world to ban salmon fish-farming as of 2021.

The damage the Blue Revolution can cause

Responsible members of the fish-farming industry like LS Aqua and Biomar are doing their best to reduce their impact but for aquaculture to become truly sustainable, the key issues of waste and antibiotic contamination must be addressed. Argentina’s ban of salmon farming is a clear indicator of the damage the Blue Revolution can cause, and far from feeding growing global populations, fish-farming is degrading local marine ecosystems while exporting the food source. According to official figures, in 2017 Argentina exported 706,000 tons of fish abroad with a total value of 1.9 billion, showing how the seafood produced around the world is not used as a local food-source, but rather is exported as a lucrative commodity.