A Blue Revolution for Oceans: Reengineering Aquaculture for Sustainability

The Problem

Global demand for protein is anticipated to skyrocket in the coming decades. Aquaculture has the potential to produce a significant proportion of the world’s nutrition. And while the current aquaculture industry is a vital producer for the global fish market, supplying 58 percent of the fish we eat, much aquaculture (particularly predatory fish and prawn) remains unsustainable, degrading both land and marine habitat, risking the introduction or spread of invasive and genetically modified species and pathogens, and polluting surrounding ecosystems. Many aquaculture farms are also economically unsustainable. Ninety-five percent of aquaculture occurs in the developing world where access to current technologies and capital, coupled with weak regulation, are barriers to change. Moreover, while aquaculture is a direct response to depleted fisheries, as an industry it relies heavily on wild-caught fish to feed captive fish. The following constraints need to be overcome to solve this grand challenge.

The Challenge

Develop aquaculture technologies, products, and systems that are more sustainable, reduce harmful by-products or environmental degradation, and replace less sustainable products & systems. Aquaculture has the potential to transform global food systems for the better. To do so requires innovations in three areas: system design, inputs, and product innovation.

1. Sustainable Design: Aquaculture farms, particularly those farming carnivorous fish, are inefficient, result in significant pollution, and can threaten human health. The challenge is to produce whole-system aquaculture farms that produce multiple species and products in a closed-loop system that generates both safe, nutritious food and does not harm the environment. Current threats to the ocean environment from aquaculture include escapement and species invasion (non-native/GMO), disease transfer from cultured fish to wild fish, and conversion of critical habitat, such as coastal wetlands and mangroves, to ponds. New designs and technologies need to address water pollution from antibiotics, herbicides, pesticides, piscicides, disinfectants, suspended solids, and other effluents. Further elements to the challenge could include rethinking where aquaculture should take place – alternative ideas may include aquaculture within cities, on barges, in reclaimed land, or farther offshore in the open ocean.
2. Rethinking Feed: The challenge is to create highly nutritional feed for aquaculture products that is sourced without environmental degradation. We would be seeking solutions for aquaculture that reduce the burden on the natural environment to produce food for people. At present, marine ingredients in feed for fish come in large part from wild fish stocks. This can deplete natural fishery populations. By incentivizing the creation of replacements for wild fish in feed, aquaculture could become significantly more sustainable, nutritious, and profitable.
3. New Ocean Products: The vast majority of aquaculture farms produce just a few products such as shrimp and certain finfish. The challenge is to vastly expand the range and quality of aquaculture products to meet rising human demand for protein while decreasing aquaculture’s environmental footprint. Fish and other species from aquaculture farms can be less nutritious than wild fish and even potentially unhealthy for humans as a result of bioaccumulation of antimicrobial carcinogens, antibiotics, and toxic algae. In addition, there is little effort to domesticate new wild fish species or to develop non-fish or shellfish products. The opportunity for more production from algae, invertebrates, and low trophic-level fish species could result in significant increases in the production of nutritious food.

Background

State of global aquaculture: While fisheries globally are nearing the point of collapse, the worldwide demand for protein is expected to continue to grow rapidly. Aquaculture as a solution is expected to at least double in outputs by 2050. To date, aquaculture food supply per capita and total production value have grown at an annual rate of almost 9% for decades, and farmed seafood has overtaken production from capture fisheries. Fish farming has enabled seafood consumption (and access to protein) to continue to increase even as marine fisheries production has flat-lined. Production is heavily concentrated in Asia, particularly China [FAO]. Given that agriculture already uses 11% of the world’s land surface [FAO], and that climate change particularly threatens global rice production [IRRI], aquaculture presents an important opportunity to meet rising demand for food.

Aquaculture as a solution is expected to at least double in outputs by 2050

Environmental health: Most aquaculture occurs in natural systems (lakes, coastal ecosystems) using underwater cages or man-made rafts, longlines or racks, which have a variety of effects on the local biogeography and overall environmental health. There is a higher risk of disease or parasite outbreaks within farms and between farmed and wild fish where highly intensive farming practices are used in small containment areas. Escaped fish may weaken the genetic strength of wild populations, bring novel diseases, and introduce exotic invasive species into ecosystems. Local waterways and ecosystems risk pollution and depletion of ecosystem health as a result of excessive fish and aquaculture waste. Just as with production of terrestrial crops, excessive use of chemicals including fertilizers and pesticides can harm marine organisms and human health. Conversion of critical coastal habitat such as mangroves, estuary mouths, sea grass beds and other sensitive systems to aquaculture is leading to the destruction of vast stretches of valuable ocean habitat and species globally.

Inputs:While helping to relieve pressure on at-risk and collapsed fisheries, aquaculture has its own unique sustainability challenges. The most prominent sustainability challenge is the feed used in aquaculture, which accounts for 40-70% of production costs and puts heavy demands on wild fisheries, which are the primary source of current feeds. With the dramatic growth in the aquaculture industry, prices for fishmeal and fish oil - prime constituents of many aquaculture feeds - are skyrocketing [Lux Research]. Fishmeal and fish oil largely come from harvested pelagic fish like anchovies and for one kilo of farmed fish it can require anywhere from 0 to 20 kg of wild fish. Further, many of the species harvested for fish meal and oil are targeted indiscriminately and even referred to as “trash fish” when in actuality the catch from these trawl catches can include numerous fish of high value and ecological significance, but which are not of any market value because of their size.

Market structure Aquaculture as an industry is poorly managed and relatively unregulated globally. According to the FAO, around 90% of the world’s 18.9 million fish farmers are small-scale producers from developing countries. Aquaculture is currently facing major economic pressures in the form of rising feed prices, which may present opportunities to introduce better and more sustainable feed technologies. Sustainable businesses can also demand higher prices for their products, create new distribution networks that help producers access larger or higher value markets, and be better insulated from price volatility.