An answer to aquaculture’s unsustainable fish feed habit?
Fri, 12/04/2020 – 00:15
Sustainability can be a game of Whac-A-Mole: We roll out a promising solution to an environmental problem, only to discover that the solution generates problems of its own.
It certainly feels that way in aquaculture. On paper, fish farms should be a win for sustainability. A third of wild stocks are overexploited, and sourcing seafood from farms should allow ocean biodiversity to recover. In practice, the industry has spent years chasing a sustainable solution for feeding the fish that it farms.
Aquaculture companies already have gone through two rounds of Whac-A-Mole for the fishfeed challenge. The question now is whether the third solution — which I’ll admit looks pretty exciting — will prove better than the first two.
Solution No. 1 was to catch a bunch of wild fish and feed them to farmed fish. This works great if fattening fish is all that matters — so well, in fact, that around a fifth of the global wild catch is now used to feed farmed fish. Of course, it’s not the only thing that matters.
“The mass exploitation of these species poses the risk of localized population collapses with knock-on effects on other marine life,” experts at the Changing Markets Foundation, a Netherlands-based nonprofit, concluded last year.
These systems divorce food production from land, dramatically cutting water use and potentially freeing up space for forests and other diverse ecosystems.
Partly because of these concerns, but more significantly due to rising fishmeal costs, the industry moved to solution No. 2: feed based on soybeans. In 1990, 80 percent of the protein in the feeds produced by BioMar, a leading provider of feed for aquaculture, came from marine sources. According to Planet Tracker, a British nonprofit, that proportion fall to just 16 percent in 2018, with soy making up the bulk of the difference.
Problem solved? Sadly not, because production of soy is a primary driver of the ongoing destruction of native ecosystems in the Brazilian Amazon and Cerrado. Several big aquaculture companies have tried to eliminate soy grown on deforested land from their supply chains, but it’s notoriously hard to track sourcing in remote regions. Soy grown elsewhere also comes with costs. In the U.S. Midwest, for instance, soy production relies on chemical inputs that damage biodiversity and generate greenhouse gases.
This brings us to an industrial facility in Decatur, Illinois, the site of what might be the third solution. Last month, Paris-based InnovaFeed announced plans to build the world’s largest insect farming facility at the site. The facility will begin rearing black soldier flies next year and eventually will scale to produce 60,000 tons of animal feed protein annually, some of which will be used in feed for farmed fish.
Research shows that substituting black soldier fly larvae for fishmeal doesn’t affect the quality of farmed fish. Insect farms also have a relatively small impact in terms of land use, water consumption and greenhouse gas emissions.
In Decatur, InnovaFeed will generate further sustainability gains by building the insect farm next to a corn processing plant operated by ag giant Archer Daniel Midlands. The larvae will feed on organic waste from the corn processing and be warmed by excess heat generated by the plant. This circular approach will allow the InnovaFeed operation to cut greenhouse gas emissions by 80 percent compared to a standalone facility, according to ADM.
Black soldier flies are actually just one element of a wave of new approaches vying to solve aquaculture’s feed problem. Companies are also growing fishmeal from algae and using microbes to convert carbon dioxide into protein. Switching to these systems can be costly, but, as Planet Tracker argues in its report, green bonds can be used to finance the transition. Some large aquaculture firms, including Grieg Seafood, are already making use of this mechanism.
Given the troubled history I just outlined, it’d be foolish to get too excited at this stage about this third wave of solutions. But I see an encouraging commonality with other new food production processes, such as cultured meat and indoor farming.
These systems divorce food production from land, dramatically cutting water use and potentially freeing up space for forests and other diverse ecosystems. If powered by renewable energy, these facilities also have low carbon footprints. This approach doesn’t gel with our intuitive idea of what constitutes “natural” food, yet an industrial approach actually might be the best way to protect and restore natural systems.