Israeli-Developed Models of Marine Integrated Multi Trophic Aquaculture (IMTA)

Modern Israeli integrated multi-trophic aquaculture (IMTA) has emerged from the Israeli freshwater polyculture, with carps, tilapia and grey mullet that started in the 1940-1950s. The dynamics, processes, environment and management of semi-intensive (several tons ha^-1 y^-1) mariculture IMTA started in the early 1970s, at the National Center for Mariculture (NCM) in Eilat, with several models that combined flow-through and recirculation features between primary (fed) and secondary (extractive) species. The seawater fishponds differed from freshwater ponds mainly in the continuous exchange with water from the open sea, to stabilize salinity and other water quality features. The primary (fed) fish was mostly the seabream (Sparus aurata), seabass (Dicentrarchus labrax), shrimp (Penaeus semisulcatus) and mullets (Mugil cephalus and Liza ramada). At first, the extractive component included microalgae, oysters (Crassostrea gigas) and clams (Ruditapes philippnmarum). In more progressive models, plastic-lined double drain ponds and tanks are used. Several other species, for example: clams, seaweed (the macroalgae Ulva spp. and Gracilaria spp.), abalone (Haliotis tuberculata and H. discus hannai), sea urchins (Paracentrotus lividus and Tripneustes gratilla elatensis), shrimp, brine shrimp (Artemia salina) are used. Wetlands planted with the halophytes Salicornia sp. and Sarcocrnia sp. have been integrated as IMTA. Recently, periphyton and drip-irrigated algal biofilters were examined and found to be practical. The research contributed to the enhancement of the sustainability, flexibility and potential for profitability of the aquaculture operation, based on the accumulated understanding about the functioning of the different units and the interactions between them. The principles developed in this research are relevant to brackishwater aquaculture, and have been applied for shrimp culture, mainly in China.