Marine mussels are a cornerstone of global aquaculture, providing a vital source of protein for millions of people, especially in middle- and low-income countries. However, climate change is poised to disrupt this fundamental industry.
A recent study published in the journal Aquaculture reveals that rising sea temperatures and shifting ocean conditions are forcing mussel habitats to move toward the poles, threatening traditional aquaculture regions while creating new opportunities at higher latitudes. The study, conducted by researchers from the Universidad Católica de la Santísima Concepción, the Millennium Institute in Coastal Socio-Ecology (SECOS), Universidad Bernardo O’Higgins, Universidade do Porto, and Universidad Adolfo Ibáñez, delves into these findings, exploring how climate change is reshaping the future of mussel farming and what it means for global food security.
The importance of mussel aquaculture
Aquaculture, particularly shellfish farming, has been hailed as a sustainable alternative to traditional land-based food production systems. It has a significantly lower environmental footprint, producing less than 1% of global greenhouse gas emissions compared to 30% from agriculture and livestock farming. However, the sustainability of mussel aquaculture is under threat as climate change alters the environmental conditions necessary for mussel growth.
Mussels are among the most farmed shellfish worldwide, with six species accounting for 99% of global production. These species include the Chilean mussel (Mytilus chilensis), Mediterranean mussel (Mytilus galloprovincialis), common mussel (Mytilus edulis), Korean mussel (Mytilus unguiculatus), Indo-Pacific mussel (Perna viridis), and New Zealand mussel (Perna canaliculus). Mussels are not only a source of high-quality, low-cost protein but also play a crucial role in coastal ecosystems by filtering water and providing habitats for other marine species.
Climate change and habitat shifts
The study used ecological niche modeling (ENM) to predict how climate change will impact the distribution of suitable habitats for six key mussel species. Researchers focused on the Representative Concentration Pathway 8.5 (RCP 8.5) scenario, which represents a high-emissions future in line with current trends.
Marine species are shifting their oceanic habitats in response to climate change, moving toward the poles or into deeper waters. “The issue with this phenomenon is that it causes coastal communities to reorganize in new ways. This has implications, as it could affect economically, ecologically, socially, and culturally important cultivated marine species, such as mussels. Unlike other species, mussels are cultivated directly in the environment, in open farming systems,” explained Felipe Torres, a Ph.D. student in Sciences with a mention in Biodiversity and Bioresources at the Universidad Católica de la Santísima Concepción (UCSC).
The results indicate that by 2050, suitable mussel habitats will shift toward the poles, with significant losses in lower latitudes and gains in higher latitudes. For instance, the Mediterranean mussel (M. galloprovincialis), a major aquaculture species in Europe, is expected to lose suitable habitats along the Mediterranean coast, particularly in southern Italy and Greece. Similarly, the tropical green mussel (P. viridis) is projected to face substantial habitat losses in Southeast Asia, a region highly dependent on this species for aquaculture.
Regional impacts and opportunities
The study highlights regional variations in how climate change will affect mussel habitats. In the Northern Hemisphere, the blue mussel (M. edulis) is expected to gain suitable habitats in higher latitudes, such as the Gulf of St. Lawrence and Northern Europe. This presents an opportunity for aquaculture expansion in these regions. However, the loss of traditional farming areas in lower latitudes could impact local economies and food supply.
In the Southern Hemisphere, the Chilean mussel (M. chilensis) is expected to experience relatively stable habitats due to the cooling effects of upwelling systems along the Chilean coast. However, increasing salinity levels driven by reduced rainfall could still pose challenges for this species.
Challenges to mussel survival
Mussels are highly sensitive to environmental changes, particularly temperature and salinity. The study emphasizes that rising sea temperatures could exceed mussels’ physiological tolerance, leading to reduced growth, reproduction, and survival. Additionally, lower salinity levels, often caused by increased freshwater input from ice melt or changes in precipitation patterns, may further stress mussel populations.
The combined effects of these stressors could have cascading impacts on marine ecosystems. Mussels are ecosystem engineers, providing habitats for other species and playing a key role in nutrient cycling. Their decline could disrupt entire coastal ecosystems, affecting biodiversity and the services these ecosystems provide.
Outlook for Chile
For Chilean mussels, no major climate-related impacts are expected, as unfavorable conditions will primarily affect the northern limit of their distribution, near Biobío and the Gulf of Arauco, but not the main farming areas. “However, in the Los Lagos region, under this climate change scenario, favorable environmental conditions for this species would persist, allowing aquaculture to continue developing,” the study explains.
The study results suggest that under the projected climate change scenario for 2040-2050, environmental conditions in Chile’s main mussel farming regions could remain relatively stable. “However, these results should be interpreted cautiously, as they are based on modeling specific variables and do not consider all factors that could influence the industry’s future,” the researchers added.
Beyond economic importance, mussels also hold ecological significance. “These organisms are called ecosystem engineers because they create environments for other species, such as algae, snails, limpets, and fish. Additionally, mussels could serve as a future alternative food source, offering low-cost, high-nutritional value with a lower carbon and water footprint than all other land-based protein sources,” Torres commented.
Adapting to a changing climate
The study emphasizes the need for proactive adaptation strategies to mitigate the impacts of climate change on mussel aquaculture. This includes relocating aquaculture operations to higher latitudes where suitable habitats are projected to expand and developing region-specific management plans to enhance resilience.
Technological advancements, such as selective breeding and improved aquaculture practices, will be essential to ensuring the sustainability of mussel farming in a changing climate. Policymakers and industry stakeholders must also prioritize spatial planning to minimize disruptions to coastal communities and food supplies.
Conclusion
Climate change is transforming the future of mussel aquaculture, with significant implications for global food security and coastal economies. The study led by Torres provides valuable insights into how rising temperatures and changing ocean conditions are forcing mussel habitats to shift toward the poles, creating both challenges and opportunities for the industry.
The study’s findings indicate that mussel species important for aquaculture are responding differently to climate change. While climate change is shifting mussel habitats toward the poles in many parts of the world, in Chile, conditions for the majority of the mussel farming industry are expected to remain suitable. “Being prepared and adapting to these changes is key to ensuring the sustainability of aquaculture and food security,” Torres concluded.
As the world faces the dual challenge of feeding a growing population and reducing greenhouse gas emissions, sustainable aquaculture practices will be more critical than ever. By understanding and adapting to the impacts of climate change, we can ensure the continued viability of mussel farming and its contributions to global food security.
Contact
Felipe I. Torres
Programa de Doctorado en Ciencias Mención Biodiversidad y Biorecursos, Universidad Católica de la Santísima Concepción
Concepción, Chile.
Email: ftorres@doctorado.ucsc.cl
Reference (open access)
Torres, F. I., Lara, C., Sillero, N., & Broitman, B. R. (2025). Climate-induced habitat shifts of farmed mussel species. Aquaculture, 602, 742304. https://doi.org/10.1016/j.aquaculture.2025.742304
