The Seafood-Energy-Water-Waste Nexus: Studying Seafood Resource Use and Waste

Why is seafood waste and resource use important?

Health professionals recommend that we eat a lot more seafood—about twice what Americans currently eat on average. While this may be good health advice, it’s alarming from a production and environmental perspective, as food production is tightly coupled to resource use.

Harvesting seafood from the wild is expensive and requires significant energy to power fishing vessels. Farmed seafood (aquaculture) requires a great deal of energy, water, and feed to grow fish in controlled environments. As a highly perishable product, seafood requires cold storage from start to finish, using further energy.  When seafood is lost or wasted, the resources that went into production, processing, and distribution are lost as well. As seafood demand grows, this environmental footprint will also grow. Seafood overall has a lower environmental impact than many land-based protein sources. Nonetheless, in this time of constrained resources and severe environmental threats, efficiency and sustainability are imperative, and require focused efforts.

This project contributes to a body of research focused on the Food-Energy-Water nexus. Nexus thinking means not only studying food, energy and water systems on their own, but also as they intertwine. Our research explores intersections and tradeoffs between seafood, energy and water systems, and the ways in which changes in any one of them can have major implications for the others. 

Our approach

This Seafood-Energy-Water Nexus project worked to identify the best opportunities for resource savings in seafood and to provide a better understanding of where and how water and energy are used throughout U.S. seafood supply chains as well as how and where seafood is wasted. The initiative brought together more than a dozen scientists across four institutions who have worked closely with the U.S. seafood industry to gather data on the top ten consumed species in the US, such as shrimp, salmon, and catfish. We gathered resource use and waste data from fishers, fish farmers, processors, distributors, retailers, restaurants and consumers – starting across the globe where key species in the U.S. seafood supply are produced and tracing paths all the way to our plates in the US. In addition to collecting quantitative data to support modeling, we also performed qualitative interviews to gather insights from these businesses and other experts regarding reasons for resource use and waste, opportunities for improved efficiency and sustainability, and other related insights and perceptions. We also performed case study research to provide an in-depth view of selected solutions. We used lifecycle assessment and other modeling to analyze the quantitative data, and qualitative data analysis to analyze interviews. Lastly, we are communicating our findings with industry, decision-makers, and consumers.

What we learned

The research has provided the first comprehensive study of resource use and food waste in the U.S. seafood system. Following are a few top findings, each with significant implications for prioritizing future efforts. For more detail, see the articles and summary briefs linked below.

• In the US aquatic system, producing one kg of edible seafood requires 96MJ of energy and 170 liters of water. This energy use is higher than most land products, however aquatic foods are more water efficient than animal proteins.
• We found particularly high environmental costs associated with air transport of fresh seafood products. Fuller accounting of and communication of the environmental costs of air transport may support shifts in modalities.
• 23% of the U.S. seafood supply is wasted each year, with the most waste at the producer and consumer levels. While this waste rate is in line with waste of other perishable food products, seafood’s high resource footprint makes its waste particularly impactful. Further, by the time seafood has reached consumers, it has required resource inputs all along the supply chain, thus increasing the harm of wasting seafood at that late stage. Consumer-focused seafood waste interventions should thus be emphasized.
• Producing fish feeds accounts for nearly a third of total energy use in aquaculture products. Working to improve sustainability of fish feed production and feed conversion ratios can reduce this footprint.
• Farmed and wild-caught seafood in the U.S. are primarily dependent on fossil fuels, and different production sectors face distinct challenges in shifting to renewable energy. Land-based production and processing rely heavily on the regional electric grid. The high costs of shifts to on-site renewable energy suggest that broader changes in the regional electric grid may be necessary to facilitate the shift to renewables. Capture fisheries will remain dependent upon fossil fuels to power vessels until alternative fuel technologies become more available and affordable. .

Achieving these improvements requires a systemic approach. Tying the reduction of waste and resource use to existing organizational goals or other operational efficiencies may help galvanize organizations to implement waste reduction strategies.

Research Team

More about the Project