Risk Is Not Equal to Impact: The Challenges of Developing a Traffic Light System to Regulate Farmed Salmon Production on an Ecosystem Scale

Abstract

We review information on salmon farming production, environmental and climatic variables covering all salmon farming areas in the Patagonia marine ecosystems over a 10-year period in Chile. With this information, we develop a semi-quantitative Environmental and Productive Risk Assessment (RA) model as a guide for the design of a Traffic Light System (TLS) for salmon farming in Chile that ensures the minimizing impacts to ecosystems and to farmed salmon themselves. This interdisciplinary study is based on the compilation and integration of historical databases from multiple public and private institutions. These databases contain information on production, fish health, oceanographic and climatic information from 79 Salmon Farming Concessions Groupings (ACS) from 2012 to 2022. The model reveals that the highest Environmental and Productive Risks occur where high cumulative production pressure (Hazard) coincides with high Environmental Sensitivity, primarily in the fjords of the Los Lagos and Aysén regions. The study provides a risk-based approach to prioritize monitoring and promote precautionary management in high-risk areas while there is not enough information on ecosystem-level tipping point indicators. Further development of a robust TLS requires the collaborative validation of ecosystem-scale data and involving all relevant stakeholders in a participatory process to establish agreed-upon risk thresholds and governance mechanisms for its implementation.