Macroinvertebrates Associated with Macroalgae within Integrated Multi-Trophic Aquaculture (IMTA) in Earthen Ponds: Potential for Accessory Production

The present work aims to evaluate the macroinvertebrate community associated with macroalgae in earthen pond systems to better understand their potential in detritus recycling and as an accessory production. Sampling took place on the settling pond of an aquaculture research station, where macroalgae permanently occurred at high densities. The results suggest differentiation between seasons but not between sites within the settling pond. Seasonal variation was observable in terms of macroinvertebrate density, biomass, and diversity. Two non-indigenous species of invertebrates were found, the crustaceans Grandidierella japonica and Paracerceis sculpta Amphipods were the most abundant group, and their high nutritional value can be exploited. Detritus and the epiphyte layer are the main food items for the invertebrates, reinforcing the advantages of these organisms being present to enhance the recycling of excess detritus and to transfer organic matter to upper trophic levels. These species, naturally present in aquaculture facilities, can improve the water quality and increase the variability of food nutrients for reared species.