Offshore aquaculture is increasingly promoted as a solution to rising seafood demand and growing spatial and ecological constraints in coastal waters. Extractive low-trophic species such as bivalves and seaweeds are of particular interest because they can contribute to food production while providing ecosystem services. Yet, sustainable offshore development depends on ecologically robust site selection informed by spatially explicit environmental data.
This study systematically analyses the peer-reviewed literature on site selection for extractive species aquaculture in open-ocean environments, with a focus on how ecological carrying capacity (ECC) is incorporated. Following PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines, studies published between 2000 and 2025 were identified through searches in Scopus and Web of Science. Fourteen studies met the inclusion criteria and were analysed in terms of species focus, geographic distribution, methodological approach, and degree of ECC integration.
Results show that GIS-based multi-criteria evaluation is the dominant method used for offshore site selection, typically combining environmental, technical, and spatial-use constraints. However, most studies stop at suitability mapping and do not explicitly address ECC. Only a limited number of studies apply mechanistic approaches, such as Dynamic Energy Budget models, Farm Aquaculture Resource Management model or coupled hydrodynamic-biogeochemical models to account for ecosystem feedbacks and sustainable production limits.
The review identifies a clear need to move from static suitability assessments towards integrated, ecosystem-informed frameworks that include adaptive thresholds and mechanistic modelling. Embedding ECC into offshore site selection will be critical for sustainable aquaculture expansion and effective marine spatial planning, particularly in the context of the growing interest in multi-use systems involving offshore wind farms.
Acknowledgment
This work was conducted as part of the AWI INSPIRES program within the program-oriented research initiative "Changing Earth – Sustaining our Future" of the Helmholtz Association.