Salmon farming vulnerability to climate change in southern Chile: understanding the biophysical, socioeconomic and governance links

Abstract

Here, we describe an assessment of climate‐change vulnerability for the salmon farming sector in southern Chile using a model that combines semi‐quantitative measures of Exposure (risks), Sensitivity (economic and social dependence) and Adaptation Capacity (measures that prevent and mitigate impacts). The evaluation was carried out in eight pilot communes representative of salmon production (marine grow‐out). Exposure was estimated with a semi‐quantitative risk assessment tool based on oceanographic, meteorological and hydrological information, mortality‐by‐cause databases, and through extended consultation with experts and relevant stakeholders. Threats included relevant changes in water temperature and salinity, declines in dissolved oxygen, occurrence of HAB s, and diseases that could be associated with climate change. Based on our analysis of the data, we divided the farming regions into four sub‐regions with distinctive oceanographic properties and superimposed the sea surface warming trend and a spatial pattern of mortality by respective cause. Reduction of precipitation and the increase of air and sea surface temperature are the most relevant foreseen climate change drivers, especially for regions X and XI . The resulting vulnerability matrix indicated that communes with higher production concentrations were more exposed, which in some cases coincided with higher sensitivity and lower adaptation capacity. Our models of four management scenarios allowed us to explore the changes in vulnerability associated with a southward movement of salmon production towards the Magallanes region. By identifying new protocols to increase adaptation and reduce vulnerability in a spatially explicit fashion, we provide policy recommendations aimed at increasing climate change adaptation and the long‐term sustainability of the sector.