Building upon the work of [1], the University of New Hampshire (UNH) completed the successful grow out and harvest of 4387 kg of cleaned steelhead trout (Oncorhynchus mykiss) during the 2023-2024 season. The operation took place at one of the UNH coastal aquaculture sites permitted for stocking up to 7000 juvenile trout in a community-scaled, integrated multitrophic aquaculture (IMTA) system called the AquaFort [2]. The AquaFort has two containment sections, each approximately 6-m x 6-m x 4.57-m, for growing fish. The fish originate as a specific strain of rainbow trout eggs (Riverence), hatched and grown in a freshwater raceway facility in Ossipee, NH. For this season, two size cohorts were investigated. The first 2000 fish cohort was stocked into the saltwater AquaFort on October 24, 2023, at a mean size of 304 grams. The second 2000 fish cohort was stocked in the adjacent containment section on December 1, 2023, at a mean size of 148 grams.
This presentation will focus on the growth and harvesting statistics from late October to early September for the first, higher performing cohort that grew to a mean size of over 2.5 kg, with some individuals approaching 5.5 kg. Datasets will show how the community-scaled system can be categorized as a non-Concentrated Aquatic Animal Production facility by the EPA-National Permit Discharge Elimination System based on small harvest biomass and feeding rates. By maintaining accurate growth and harvest datasets, this seafood system can also be managed to keep stocking densities well below the nominal threshold of 22 kg m-3, appropriate for fish welfare. Most of the fresh products were distributed and sold to local markets in Portsmouth, NH with some hot-smoked processed in Boston, MA. Part II of this presentation will discuss the potential economic benefits and emerging markets of the AquaFort in NH and beyond.
[1] Chambers, M., Coogan, M., Doherty, M, Howell, H. 2024. Integrated multi-trophic aquaculture of steelhead trout, blue mussel and sugar kelp from a floating ocean platform. J. Aqua. 582:740540. https://doi.org/10.1016/j.aquaculture.2024.740540.
[2] Chambers, M.D., Coogan, M., Doherty, M., Berghahn, E., Fredriksson D.W. 2024. AquaFort, a floating, integrated multi-trophic aquaculture system. W. Aqua. Mag. 55(3): 34-36. https://www.was.org/Magazine/2024/03/34/#zoom=z.