The global population is increasing along with the demand for secure and sustainable seafood. Aquaculture production is growing to meet this demand, but the heavy reliance of most culture systems on the ambient environment and ecosystem services suggests an inherent vulnerability to climate change. In order to design and implement effective climate change adaptation, policymakers and growers need to understand where their industry is vulnerable and how climate change stressors may affect their sector. Climate change vulnerability assessments are an internationally recognized assessment process that can help growers and decision-makers plan for climate change. This form of assessment is relatively new to aquaculture but has begun to see application to regional culture systems such as salmon in Chile, multi-species in Korea, and oyster culture in Australia.
Vulnerability assessments are generally based on three indices: ‘Exposure’, ‘Adaptive capacity’, and ‘Sensitivity’, which are combined to form an overall vulnerability index. Data inputs for these indices can be quantitative, qualitative, or a combination of both (semiquantitative), and can be challenging to combine, given different data types and collection methods. For example, quantitative inputs such as wind and wave exposure may have magnitude and frequency data generated from climatic models, whereas qualitative inputs such as farmers’ perceptions of risk are assessed through questionnaires and interviews. The result is typically a semi-quantitative model, that translates different data types into a final understandable value. The availability of data or scale may also be a challenge, as some regions or species may have more available data than others. In this case, a more qualitative approach, such as expert opinion, may be sought.
Despite its limitations, climate change vulnerability assessments are an important tool for guiding decision-makers and prioritizing adaptation efforts. Here we present current practices and limitations of climate change vulnerability assessments in consideration of application to aquaculture.