As a nascent industry in the United States, open ocean (also referred to as “offshore”) aquaculture has the potential to positively contribute to domestic seafood supplies. However, it also has the potential to cause environmental damage if the risks and impacts of the farms are not well understood. Due to a lack of domestic operations, examples of commercial open ocean aquaculture farms in other nations can provide insights into which species might be most suitable for open ocean cultivation, and the specifics of cultivating them offshore. Broad studies of the environmental benefits, risks, and innovations for open ocean aquaculture have been conducted, but lack the granularity of how the environmental and fiscal sustainability of an open ocean farm, which will likely vary depending on species cultivated.
The purpose of this report is to highlight what species appear to be viable candidates for open ocean aquaculture cultivation, with a focus on those that may be optimal for farming in the U.S. This report identifies three categories for viable species: finfish, shellfish, and seaweed and describes each species’ specific needs, ecological risks and benefits, and current commercial potential. The species analyzed in each category were selected for at least one of three reasons: 1) Whether they have actually been farmed in U.S. waters or abroad, 2) repeated mention in literature and by industry advocates as an ideal open ocean species, and 3) physical compatibility with the open ocean and exposed conditions. The finfish species that seem most likely to be farmed in U.S. open waters in the near term are: cobia (Rachycentron canadum), kanpachi (Seriola dumerili and Seriola rivoliana), Atlantic salmon (Salmo salar), and steelhead trout (Oncorhynchus mykiss). The species that appear to have the most potential to be farmed in the future, but haven’t yet been grown at commercial or semi-commercial scales, are: nenue (Kyphosus vaigiensis), California yellowtail (Seriola dorsalis), mutton snapper (Lutjanus analis), Florida pompano (Trachinotus carolinus), Atlantic cod (Gadus morhua), red drum (Sciaenops ocellatus), bluefin tuna (Thunnus thynnus & Thunnus orientalis), red snapper (Lutjanus campechanus), sea bream (Pagrus pagrus), and mahi-mahi (Coryphaena hippurus). Blue mussels are the highlighted shellfish, and giant kelp, bull kelp, and other Australian native algae are the featured macroalgal species.