The practice of growing low-trophic level species (LTA), primarily filter feeders, has been recognized for its sustainable food production potential while achieving the sustainable development goals set by the United Nations. However, LTA generally occurs in open systems where there is no control of the culture environment which leaves cultured organisms susceptible to climate change impacts. As invertebrates that cannot regulate their temperature and salt content LTA species are at the mercy of environment and climate change can impact their welfare.
To better understand climate change welfare impacts on LTA species, we performed a risk assessment for Västra Götaland. As the first step in the risk assessment, we summarized the expected climate change impacts for Västra Götaland based on model projections from the Swedish Meterological and Hydrological Institute (SMHI). Additionally, physiological tolerance and expected responses for commercially important LTA species relevant to Västra Götaland were taken from the literature. Physiological tolerances were then compared with projected climate change impacts to develop a list of risks, both positive and negative.
Each risk was evaluated in a consensus-based round-table expert workshop and prioritized based on stakeholder input in a separate workshop. Following the risk assessment, a short literature review was undertaken to identify possible adaptation actions. During our risk assessment we identified 22 climate mediated welfare risks for present day conditions that merit some form of adaptation or mitigation action. When considering future conditions, based on climate scenario RCP 8.5, the number of risks that required adaptation or mitigation actions roughly doubled, increasing by 22. Risks identified included, but were not limited to, direct effects such as extreme temperature and salinity as well as indirect effects such as changes to food availability. A risk management workshop with stakeholders and experts produced four recommended adaptation actions, prioritized based on their ease of implementation, potential impact, and number of effected risks: (1) More research to reduce uncertainties surrounding climate risks, (2) increased monitoring and modelling efforts to better predict and detect hazardous conditions as well as the development of emergency preparedness plans, (3) the capacity for submerging culture cages below the pycnocline temporarily to avoid hazardous surface conditions, and (4) more thorough and data-driven site selection to identify climate resilient culture areas.
Fiskebäckskil: IVL Svenska Miljöinstitutet, 2025.