Location: Cool and Cold Water Aquaculture Research
Project Number: 8082-31320-002-01-A
Project Type: Cooperative Agreement
Start Date: Apr 1, 2015
End Date: Mar 31, 2020
Recirculating aquaculture systems (RAS) provide control of water quality and temperature to optimize fish production and health, provide barriers that prevent escape of fish and entry of pathogens, contain and remediate waste flows to curtail environmental impact, and minimize water use. RAS can allow a commercial fish farm to locate where power, feed, or oxygen is relatively inexpensive, where environmental impact can be minimized, and/or adjacent to their primary markets. However, RAS are dependent on relatively larger energy inputs than traditional flow-through or net-pen systems. Thus, strategies are required for reducing energy consumption and improving waste disposal, which both are major factors in a fish farm’s overall life cycle assessment. In addition, production techniques must be developed to improve biosecurity and reduce stress and disease outbreaks in fish cultured in closed containment systems. This work will integrate research and technology advancements, and resolve current and emerging constraints to the expanded use of land-based, closed containment systems for the production of safe and nutritious salmon and other cool- and cold-water species. Objective 1. Develop technically advanced, environmentally compatible, and sustainable closed production systems and techniques. •Sub-objective 1.1 Optimize the cost and effectiveness of technologies to remove nitrogen and phosphorus from recirculating aquaculture systems and their effluent. •Sub-objective 1.2 Increase the energy efficiency of CO2 degassing technologies. •Sub-objective 1.3 Use refinements in water treatment process design and economies of scale to decrease the capital cost required per tonne of fish produced within water recirculating systems. Objective 2: Improve salmonid performance, health and well-being in land-based systems through research on nutrition, rearing environment, and control of pathogens and fin erosion. •Sub-objective 2.1 Field-test rainbow trout germplasm resources when reared to 2kg harvest size within intensive water reuse systems and ID top performing individuals and families. •Sub-objective 2.2 Compare the effects of alternate protein (zero fish meal) versus fishmeal-based diets on growth performance and welfare of select families of Troutlodge rainbow trout when reared to 2 kg. We will also measure water quality, water treatment process performance, and waste production rates in recirculating aquaculture systems operated at low flushing rates. •Sub-objective 2.3 Identify strategies to minimize losses of Atlantic salmon smolt to Saprolegnia infections following vaccination in water recirculating systems.
The ability to provide U.S. consumers with high-quality, sustainably-produced seafood hinges upon research that supports increased domestic aquaculture production and the development of new and improved technologies. This proposed work encompasses several USDA ARS Action Plan components, primarily technology development for sustainable production systems, alternative protein investigation, and disease prevention. The first objective, which is focused on recirculating aquaculture system (WRAS) technology development, will investigate two water quality-improvement technologies: (1) low-cost woodchip bioreactors for nitrate removal from aquaculture effluents, and (2) membrane biological reactors that produce a clean filtrate for reuse in the WRAS, which eliminates makeup water flushing and the point-source discharge. Refinement of water treatment processes and use of economies of scale to reduce capital costs of WRAS will also be a key focus. This work will also investigate a new and potentially more energy efficient and cost-effective carbon dioxide stripping technology. Within the second overarching objective, we will evaluate the performance of commercially available rainbow trout strains (fingerling to 2 kg) cultured in WRAS, and will identify strategies to minimize Saprolegnia infections in Atlantic salmon smolt cultured in WRAS after vaccinations. In addition, pressing societal concerns about the sustainability of fish feed and the rising cost of fish meal provide the emphasis to compare the effects of alternate protein (zero fish meal) and fishmeal-based feed formulations on trout health and performance, waste production, and water quality.