Five Aquaculture Questions for Dr. Jillian Fry

Rocco Pallin

Food Tank had a chance to talk with Dr. Jillian Fry, director of the Johns Hopkins Center for a Livable Future Public Health & Sustainable Aquaculture Project. The Center aims to create healthier, more resilient, and more equitable food systems in partnership with researchers, policymakers, advocates, and communities. Jillian has a special interest in the public health and environmental consequences of industrial food animal production. Read on to learn what Jillian has to say about her interest and research in animal food production and aquaculture.

Food Tank (FT): How did you first become interested in industrial food animal production and aquaculture?

Jillian Fry (JF): My younger sister taught me about industrial food animal production, the dominant model used to produce meat, dairy, and eggs in the United States and other high-income countries, when I was a college student in 2002. It only took a few online videos and reports for me to alter my diet and start sharing what I learned about the massive resource use, environmental pollution, and mistreatment of workers and animals with people around me, but I didn’t make the connection between food production and my public health studies/career until I became a doctoral student at the Johns Hopkins Bloomberg School of Public Health in 2007. I connected with the Johns Hopkins Center for a Livable Future (CLF) in my first year and have been working on food systems, environmental health, sustainability, and public policy with the Center ever since. Upon graduating in 2012, I became the director of the Public Health and Sustainable Aquaculture Project at CLF.

Aquaculture, and seafood in general, is a fascinating and complex topic—involving hundreds of species— and I enjoy researching this piece of the food system especially because I see a need to incorporate better aquaculture issues into the larger body of food systems work. When we think about seafood, we need a global perspective. Seafood is one of the most highly traded food types, and it generally moves from low- and middle-income countries to high-income countries. The U.S. is the second largest importer of seafood in the world, so we have tremendous power to influence how it is produced abroad. Interestingly, the U.S. is also the fifth largest seafood exporter, although some of that seafood is processed overseas and then re-imported. The U.S. does a pretty good job managing our domestic fisheries, and our federal government is working on increasing traceability requirements for the seafood supply chain, which should cut down on overfishing, mislabeling, illegal fishing, and human slavery occurring overseas.


FT: Why is it important for consumers to know more about what they’re eating when they consume wild or farmed fish?

JF: Global production of wild-caught fish has been flat for many years, and farmed seafood, or aquaculture, has grown quickly over the past few decades and now produces half of the seafood we eat. Aquaculture can be highly sustainable, or resource intensive and polluting. Production of aquatic plants and shellfish (e.g., oysters, mussels, clams, scallops) requires no feed inputs and can actually help reduce excess nutrients in a waterway. Aquatic species that do require feed need less per kilogram of animal produced compared to cattle and hogs, which is a big benefit in terms of sustainability. 

There are some similarities between intensive aquaculture and livestock production. For example, when many animals are confined in a tight space there is an opportunity for diseases to spread quickly, and veterinary drugs (e.g., antimicrobials) and other chemicals are used to prevent or control outbreaks, leading to public health risks via contamination of the surrounding environment and the food products. The spread of antimicrobial-resistant pathogens due to use of these drugs is especially concerning because consumers and residents living near an operation can become infected with these hard-to-treat pathogens. Depending on the farming methods used, pollution can also come from fish waste and uneaten feed, and diseases can be passed to nearby wild aquatic animals. Recirculating, or land-based, aquaculture is a growing sector that dramatically reduces disease exchange and discharge of pollution into the environment.

There are many efforts underway to move wild and farmed seafood production towards sustainability, including certification programs, buying guides, and new regulations. Most consumers are familiar with Seafood Watch from the Monterrey Bay Aquarium, which provides guidance on what species, catch or farming method, and source country are best to choose for sustainability; we should expand use of this and other guides by consumers to decrease demand for unsustainably produced seafood, and support upstream policy changes aimed at improving transparency and ending the most destructive production practices.

FT: What recent changes have occurred in the ways farmed fish are raised and why?

JF: The aquaculture industry is growing and intensifying, meaning more fish are being produced using higher stocking densities and complete feeds from a feed mill. Nutrition requirements vary by species, and many feeds incorporate fishmeal and fish oil (mostly made from small, wild-caught fish like anchovies and sardines). Harvests of these fish are not expanding, so the aquaculture industry has been using more plant-based feed ingredients (e.g., soybeans, corn, rapeseed, and wheat) to allow production of farmed seafood to grow. I, along with several colleagues, conducted an analysis on this topic and concluded that this change can alter the nutritional profile of farmed seafood, links aquaculture production to terrestrial crop agriculture, and changes the environmental footprint of aquaculture.

FT: What sorts of negative health effects might result from this change?

JF: Farmed fish get their health-promoting omega-3 fatty acids, EPA and DHA, from their feed, and specifically from fish oil. There is evidence that replacing fish oil with vegetable oils changes the ratio of omega-6/omega-3 fatty acids in farmed fish, which may have implications for human nutrition and health. Some aquaculture producers use specific strategies to reduce use of fish oil while maintaining omega-3 levels, such as “finishing feeds” that contain fish oil and are fed to fish for a short period before harvest. The human health impacts of altered fatty acid profiles are not clear, but intake of the omega-3 fatty acids EPA and DHA are associated with improved cardiovascular health and neurodevelopment.

The changes in feed composition also impact the environmental footprint of farmed seafood production and environmental health risks. Like fish-based ingredients, resources such as land, water, and fertilizer used to produce feed crops are also limited. Aquaculture’s environmental footprint likely now includes increased nutrient and pesticide runoff from the industrial crop production needed to supply fish feed. This runoff is a key driver of water pollution globally, and can negatively impact public health. Depending on where and how feed crops are produced, plant-based fish feed could be indirectly linked to negative health outcomes for agricultural workers and nearby communities due to exposure to air, water or soil contaminated by nutrients and/or pesticides.

FT: What kinds of research and policy changes would you like to see prioritized for aquaculture?

JF: Aquaculture research and policy efforts need to be responsive to trends in farmed fish production. We should be monitoring the nutritional content of farmed fish and exploring human health impacts of changing feeds. Also, the aquaculture industry should assess the environmental footprint and public health impacts of their crop-based feed ingredients and seek those produced using sustainable methods. Farmed seafood products can be a great choice in terms of health and sustainability, but there is high variability; consumers and retailers need guidance that is up-to-date and accounts for food safety, nutritional content, environmental impact, and social responsibility.

The U.S. federal government is working to expand our domestic aquaculture industry, and these efforts should give more weight to farmed seafood that does not require feed or has a lighter footprint for other reasons. The U.S. aquaculture industry currently accounts for less than 1 percent of global aquaculture production, so there is significant room to grow. Federal agencies could partner with various stakeholders to market sustainable, domestic seafood (farmed and wild) through local and regional supply chains in the U.S. to increase local consumption of seafood products. This would allow consumers to explore their local/regional food system, which is presently quite difficult due to a lack of transparency and high consumption of imported seafood in the U.S.