Mytilus galloprovincialis's role in Integrated Multi-Trophic Aquaculture (IMTA): A comprehensive review

Sustainable mussel farming practices are critical for maintaining production and enhancing growth of the low trophic aquaculture sector. The concept of Integrated Multi-Trophic Aquaculture (IMTA) and incorporating mussels as extractive species, holds promise for enhancing overall system efficiency, nutrient cycling, and environmental sustainability. This review delves into innovative aquaculture techniques emphasizing the synergistic relationships between Mytilus galloprovincialis and other species such as seaweeds and deposit feeders that prioritize environmental stewardship by absorbing excess nutrients, processing organic waste, and including best management practices for waste mitigation. Marine spatial planning (MSP) through IMTA development can support optimal capacity building scenarios, incorporating ecosystem services and social benefits. This review explores the different aspects of mussel biology, ecology, aquaculture, sustainability, and future perspectives on the basis of literature data, with a context of capacity building in the Atlanto-Mediterranean area. The literature data were analyzed in order to explain interactions between primary species and mussels as extractive species. We developed conceptual models at three different scales—small, medium, and large—to define the optimal growth performance of mussels in relation to their distance from the aquaculture nutrient source. The consistent trend favoring medium-scale conditions has led us to conclude that mussels predominantly extract nutrients indirectly, primarily through the phytoplankton blooms resulting from fertilization. On this basis, we recommend that the marine spatial integration of mussels must be designed according to these models to optimize production while mitigating the side effects of fish cage aquaculture.