Green Ocean Hunters? The Environmental Effects of Fishing and Aquaculture, Part 2

Green Ocean Hunters? The Environmental Effects of Fishing and Aquaculture, Part 2

Last week, in part one of this article, we ended with the tragedy of the commons and the question of whether overfishing is a logical consequence of human nature. Luckily, not all things are as bad as they seem. Let’s get back to our effort to increase comprehension and scroll to page 18 of Frank Asche’s report (Green Growth in Fisheries and Aquaculture Production and Trade). He seems quite confident there.

[T]here is no doubt that aquaculture can be carried out in a sustainable manner, independent of the level of intensity. Therefore, the real issue with aquaculture and sustainability is whether farmers choose to use sustainable practices. This will be an issue primarily of local regulations and governance, and is one area where green growth policies can have a major impact.


No Fish Meal Trap If Vegetable Oil Is Substituted for Fish Oil

Again on the positive side, he also deconstructs the fish meal trap. That’s the problem I mentioned in the introductory sentence of last week’s article: when aquaculture depends on wild catch to provide fish farms with fish protein, aquaculture can never be a solution to overfishing. Fortunately though, Asche wrote that we are not actually trapped (see pages 14-15):

Global aquaculture and fish meal production, from Green Growth in Fisheries and Aquaculture Production and Trade (PDF), page 16

The “fish meal trap” is the hypothesis that aquaculture is environmentally degrading because increased demand for feed leads to increased fishing effort for the wild species used to produce the feed and thereby threatens the viability of wild fish stocks, and that the growth in aquaculture production will be limited by the availability of wild fish to be used as feed in aquaculture production (Naylor et al.. 2000). […] Carnivorous species, such as salmon and sea bass, are most exposed to the fish meal trap as they are using the highest share of marine inputs in their feed. However, also some omni- or herbivorous species, such as tilapia, pangasius and shrimp are exposed because increases the growth rate, and the economic viability of the industries largely depends on this. […] The extent to which increasing demand for fish meal leads to greater fishing effort is related to the management regime in operation for the fishery in question. With a properly working management system, increased demand for the species in question cannot threaten the fish stock. Hence, the issue of whether growth in aquaculture production can lead to unsustainable capture fisheries is primarily a fisheries management problem. […] Yet, in order for increased demand from aquaculture to have an impact, aquaculture growth must increase total demand for fish meal. There are two relationships that can prevent this. First, fish meal and fish oil has for a long time been a part of the vegetable oil and meal markets. When this is the case, there are users of fish meal and oil that will substitute away from these products in response to increased demand from aquaculture. As long as this happens, there will be no increase in aggregate demand for fish meal and oil. […] Aquaculture producers accordingly have strong incentives to reduce the share of marine ingredients in the feed, something that has happened (Tacon and Metianen, 2008). Hence, […] aquaculture production has been growing without any effect on fish meal (and oil) production. In fact, fish meal and oil production from wild capture fisheries are going down according to the International Fishmeal Producers Organization, but the total production remains relatively stable because an increasing share of cut-offs from fish processing is being used. This share is now approximately 25% of total fish meal production. (pp. 14f.)

Short-Term Interest vs. Long-Term Benefit

So we’re not lost? Well, there are, after all, certain interests that make certain people quite certain to not shift to sustainability. We’ve heard it before, and we’ll hear it again: why would people invest in the future for the benefit of others, when the same people could rather achieve a benefit to themselves in the present? We know the problems of our times, and we’re not short of ideas for improvement. But, wherever you go, short-sightedness and narrow-mindedness hinder sustainability. The world needs glasses and broadened minds!

There are a number of aspects related to fisheries management that can be significantly improved from a green growth perspective. The most important is to reduce waste in different dimensions. Many fisheries management systems give incentives to overfishing, over-capitalisation, discarding and are also promoting such behaviour by subsidies. Many of these problems are recognised and should be at the core of green growth policies for fisheries. […] The most important barriers to implement greener policies in fisheries management seems to be the classical tension of green growth policies in that sound long-run policies requires short term investments and may contradict short-term objectives. (p.12)

Comparative LCA for Seafood in GB

Management of the fisheries is recommended not only by Asche. The extensive report Sustainable Production and Consumption of fish and shellfish – Environmental Impact Analysis (PDF) comes to the same conclusion. Rod Cappell, Sarah Wright and Fiona Nimmo wrote it for the British Department for Environment, Food and Rural Affairs (defra) in 2007, listing a plethora of fish species, fisheries and transport modes, and their respective effects on the environment. This report is not just about carbon footprints. Much more, it attempts to provide complete information on the entire life cycle of seafood. When you read the PDF, don’t be confused by its retention of the printed form’s pagination (the TOC, for instance, begins on the PDF’s p. 31); this minor difficulty does not stop me from mentioning this comparative LCA and especially the authors’ conclusions:

For fishing it is evident that ecosystem impacts during the catching phase are the most significant followed by fuel use associated with this phase. It is therefore effective fisheries management that will ensure sustainable production through targeting sustainable stocks, minimising capture and damage to non-target species and habitats. Fisheries management measures are also key to reducing the sector’s fuel use by moving towards improved operating efficiency. […] The impacts of aquaculture on the environment are again dominated by ecosystem effects; from the feed using fishmeal and fish oil from industrial capture fisheries and from the waste resulting from the on-growing operation. Ultimately the significance of the feed is mainly dependent upon the sustainability of harvesting from the source capture fisheries, but other feed production aspects such as energy use and transport of feed are important. (p. 135)

Valid for Switzerland, this carbon footprint shows how heavily the packaging materials affect the overall emissions of mackerel and herring in cans. 4.5 – 6.5 kg CO2eq are generated for 1 kg of fish purchased in Swiss supermarkets.

Losing Perspective? Product Declarations Help

Yes, I mentioned it before, the topic is complex. Because of this, Cappell et al. recommend simplifying consumer information through environmental product declarations (EPD) based on LCAs:

When the complexity of assessing type, significance and comparison of the various impacts associated with seafood products [is] combined with the diversity of species and origins, it is clear why consumers are reliant on retailers and labelling schemes to steer sustainable seafood buying decisions. To achieve sustainability in a wider sense, the current focus on catch and production quantities may need to shift towards consideration of the ways in which seafood is caught and produced. LCA offers an opportunity to identify areas where practice could be improved, which may be in addition to the current control methods used in fisheries management. (p. 136)

And it is not hard to find experts in this field, too. A few are G. Parkes, S. Walmsley, T. Cambridge, R. Trumble, S. Clarke, D. Lamberts, D. Souter and C. White. Their Review of Fish Sustainability Information Schemes (PDF) from October 2009 is 194 pages long. “What makes a good fish sustainability information scheme?” is what they ask. Their 12 page answer can be found on pp. 76-88. In brief, the label has to satisfy 7 different requirements. Most importantly, however, labels have to conform to the “FAO guidelines for ecolabelling of marine capture fisheries”. These focus on management systems, desired and actual fish stocks and ecosystem side effects. From p. 91 on, the most common fish sustainability information schemes are reviewed in detail. Among them are organic labels like those from Naturland and the Soil Association, the WWF associated Marine Stewardship Council label, local conservation society labels and also NGO recommendation leaflets.

So what do we learn? Governments should cut harmful subsidies; fishermen, authorities and academia should agree on management plans; and customers and businesses should buy fish only from places which provide complete labels, or where staff can explain the seafood’s origin and mode of transport. And above all, why don’t we just convert to being weekday vegetarians and save both fish and meat for special occasions? Win-win for fish stocks and for quality of life.

Article image by Moritz Bühner, taken in a restaurant in Hong Kong which sells locally caught fresh seafood.



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