IntroductionThe food-energy-water (FEW) nexus highlights the interdependencies between the systems that people rely on for these essential resources. For example, globally, over two thirds of freshwater withdrawals are used to produce food, and another 10% is used during energy generation. In addition, the food system uses one eighth of global net energy. Seafood is a nutritionally important food, and it is critical to use freshwater and energy resources efficiently throughout seafood supply chains to safeguard future supplies and to reduce environmental impacts. Diverse seafood production methods result in highly variable resource use across supply chains, which may contribute to siloed efforts within supply chains to improve efficiency, instead of larger efforts that involve multiple seafood supply chains. Additionally, efforts to develop and implement efficiency strategies must be informed by fishers, aquaculturists, processors, and other seafood supply chain actors to avoid investing time and resources into strategies that will have low uptake. A significant proportion of seafood is imported into the U.S., so engaging with industry and stakeholders in the U.S. and abroad is critical for understanding and improving the FEW nexus associated with seafood consumed by Americans.MethodsTo understand how resources are being used, current and potential strategies to improve resource use, and relevant motivations and barriers, we conducted 47 semi-structured interviews from 2019 to 2021 with seafood supply chain actors, including producers and processors. Seafood supply chains included were farmed catfish produced in the U.S., farmed pangasius and shrimp produced in Vietnam, farmed Atlantic salmon produced in Norway, and wild-caught sockeye and pink salmon caught in the U.S.ResultsWe provide detailed descriptions of stages within each supply chain regarding resource use and efficiency strategies, and report higher-level findings that apply across supply chains. There was variation across settings regarding how resources are used and opportunities and barriers for improving efficiencies, but we also found commonalities in settings, indicating that resource-saving strategies or innovations could lead to increased efficiency across multiple supply chains. Interviewees shared that cost savings drove past adoption of, and high interest in, energy conservation practices. Generally, direct costs did not motivate reduced use of freshwater, but associated costs like energy to run pumps and supplies to treat contaminated surface water drove interest in reducing water use.DiscussionEfforts to improve resource use in the U.S. seafood supply should focus on identifying and scaling-up strategies that (i) involve improved efficiency of more than one resource and/or (ii) apply across multiple settings. This work should involve partnerships between industry, government agencies, and academic researchers, and should be informed by supply chain actors’ experiences and insights. The qualitative insights from this study encompass rich descriptions of FEW-relevant factors at the level of specific supply chain stages as well as findings across six major seafood supply chains in three countries. The study provides an essential complement to existing quantitative characterizations of resource use, and enables nuanced and informed responses to challenges.