The case for using fishmeal and fish oil in feed for farmed Atlantic salmon (Neil Auchterlonie)
In response to a press release made by Australian Ethical that refers to the selling of a salmon farming company’s shares on the basis of concerns about the sustainability of farmed salmon feed supply, I wrote the following:
The text in the press release specifically criticises the use of marine ingredients in sustainable farmed salmon feed, and refers to your organisation’s position of not investing in salmon farming companies unless they reduce their use of wild fish as feed stock. I have also read the information on your company’s website “Why we need to stop fishing the high seas” as further background to understanding the position of Australian Ethical. As a representative of the global fishmeal and fish oil industry, and as a consequence of reading that text, IFFO feels obliged to write and provide you with some information on the marine ingredients industry and the supply of fishmeal and fish oil to the aquafeed industry specifically.
Aquaculture, as seems to be acknowledged on the Australian Ethical website, is well positioned to make a great contribution to global food security, and your website notes the potential to support a reduction in over-fishing. There are several benefits to the provision of protein from aquatic sources compared to terrestrial systems including the efficiency of feed and protein conversion and these are widely understood. Aquaculture is going to have a very important role to play in providing enough food for an ever-growing human population as we move through the 21st Century. We are, however, troubled by some of the common misunderstandings about the production of fishmeal and fish oil and its use in aquafeeds, some of which appear to be repeated in the Australian Ethical written material. In this instance those misunderstandings are being communicated in a way that damages the support for a developing aquaculture industry that carries benefits to society at a time when these are very much needed.
In the text on your organisation’s website Australian Ethical draws attention to the sustainability of wild fish stocks that provide raw material for fishmeal and fish oil production. It mentions a move towards more plant-based protein for aquafeed substituting the marine ingredients that are used, the implication being that the terrestrially derived ingredients are in some way more environmentally-sustainable than the marine ingredients. This is, in fact, not a straightforward conclusion that may be made, and although IFFO acknowledges the importance of other ingredients in providing the volume of supply required for a developing industry we regard this from an “As well as, rather than instead of” position. Fishmeal and fish oil were the foundations of modern fed aquaculture and will continue to be so for many years to come, for some very important reasons.
Firstly, addressing the environmental concerns we note that because these fisheries are pelagic in nature, there is no issue with environmental damage from the fishing process itself. Usually these pelagic species are caught by purse-seine netting which has no impact on the sea bed. The fishing process itself also tends to be highly selective in nature because the fisheries are often dominated by a single species, such as the mainstay of global fishmeal and fish oil production, the Peruvian anchoveta, Engraulis ringens and so bycatch levels are often extremely low. Those pelagic fisheries stocks tend to be fast-growing, early maturing, and highly productive, making them comparatively straight forward to model and manage compared with other more traditional fisheries such as cod or halibut for example. The population dynamics of an ecosystem largely dominated by a single species permits for better managed fisheries. Some recent science shows that variation in physical environmental parameters such as temperature, ocean currents, is likely to have a more pronounced effect on stock size variability than fishing does.
But the material doesn’t always come from whole fish. It is frequently overlooked that the contribution of seafood processing by-products (filleting trim and other waste materials) to the total volume of fishmeal and fish oil produced is significant. It is currently estimated to be around 35% and expected to increase to 50% of total within the next decade. The FAO actually predicts this to be 49% of raw material supply by 2022. Our industry defines by-products as fish not suitable for human consumption or where catch is occasionally landed in surplus to local production capacity and would otherwise be treated as waste. In both instances, the use of fish for reduction is not detracting from direct human nutrition.
Disposal of fish waste is, at best, an undesirable environmental impact that needs to be carefully managed. This often incurs cost in processing and transporting waste to suitable disposal locations. At worst, there is not only cost but also unacceptable environmental pollution. Calls for fishmeal and fish oil to be formulated out of aquaculture diets ignore the impact this would have on the approximately 6 million tonnes of recycling of wastes now occurring.
The vast majority of whole fish used for fishmeal and fish oil production are small, bony species for which there is no direct human consumption (DHC) market. If there were a DHC market, it would provide better financial return to fishers than reduction into protein and oil for animal feed, and the market itself would change to accommodate this. Some governments have tried but failed to change the fishery to move into the DHC market. For example, despite years of promoting the human consumption of the largest reduction fishery in the world by the Peruvian government, DHC for the anchoveta is still minimal at less than 5% of the catch. We have seen other species like Mackerel and Herring, previously used for reduction, now finding DHC markets – what is left is because no markets exist. If the stock is responsibly managed, as in the case of Peruvian anchoveta, there should be no reason why the local economy cannot benefit from harvesting the species for indirect human consumption via animal feed.
Nutritionally fishmeal is important for aquafeeds, and especially for carnivorous species such as salmon because it contains many of the micronutrients required by the species – understandable when you consider that the salmon as a species evolved to consume other fish. Those micronutrients include a number of essential amino acids, vitamins and minerals, many of which the vegetable-based ingredients are deficient in and the feed manufacturer has to supplement. I note that Australian Ethical has a position statement on animal welfare, and you may wish to consider how important meeting the requirements of farmed fish lies from a welfare perspective. Some vegetable-based ingredients contain so-called anti-nutritional factors (ANFs) that can affect the digestion and absorption of the available nutrients in the feed. Whilst the soya meal and other ingredients are processed to remove these compounds, the process is energetically and financially costly, and no doubt adds an additional environmental cost. As I’m sure you realise, terrestrial ingredients themselves have a number of environmental impacts such as land use, irrigation, use of fertilisers, and it is a far from simple case to say that the impact of one is better than the impact of another. LCA (Life Cycle Analysis) studies have been looking at aquaculture systems for more than a decade now, and this is regarded as a very complex field.
Further, fish oil is only produced by the manufacture of fishmeal. Although marine algae are being cultured to produce the long chain Omega 3’s EPA and DHA, the most cost effective and available source of these fatty acids for the global nutritional supplements market is still fish oil. For animal feed use and the health of farmed fish, there is currently no other viable source of Omega 3 fatty acids. Salmon cannot be farmed on feed that does not contain EPA and DHA, because those compounds are necessary for the farmed salmon’s health.
Our industry has embraced sustainability and, in 2009, launched an independent standard for the certification of fishmeal and fish oil production. The standard was developed collaboratively with the involvement of a stakeholder group of NGOs, fish farmers, feed companies and retailers and requires independent assessment of raw material sources and manufacturing systems by an ISO17065 accredited Certification Body. Well over 40% of the world’s production is now within the scheme, and that compares very favourably against the certified volume of vegetable-based feed ingredients available globally.
I hope that the above text is of some interest to you, and hope that Australian Ethical will not be so critical of marine ingredients use in aquaculture diets in future.
Neil Auchterlonie, Technical Director, IFFO