What is sustainable aquaculture?

Aquaculture is a rapidly growing industry, supplying nearly 50 percent of the world’s seafood and playing a crucial role in global food security. However, as demand rises, so do concerns about its business sustainability status. While sustainable aquaculture has the potential to be a solution, unsustainable practices raise questions about its long-term viability. 

The key to ensuring a sustainable future for the industry lies in implementing responsible farming methods that balance environmental, economic, and social sustainability. But is aquaculture truly sustainable, and how can the industry evolve to meet growing food demands while minimising its footprint?

Is aquaculture sustainable?

Although aquaculture has the potential to be a sustainable solution to global food security, the environmental impact of aquaculture depends greatly on how it is practised. 

Sustainable aquaculture explained; how is aquaculture sustainable?

Sustainable aquaculture is a responsible approach to fish and seafood farming that balances environmental, economic, and social sustainability. Below are some of the key principles of the approach.

• Environmental responsibility: For aquaculture to be sustainable, it must focus on reducing habitat destruction, water pollution, and greenhouse gas emissions.
• Efficient resource use: The industry must implement practices to tackle waste, such as optimising feed conversion ratios (FCR), using alternative feed sources, and implementing water-saving and recirculating aquaculture systems (RAS). 
• Biodiversity protection: Sustainable aquaculture should strive to protect and conserve biodiversity. For instance, by avoiding overfishing and disrupting wildlife populations, as well as promoting polyculture and Integrated Multi-Trophic Aquaculture (IMTA) to enhance ecosystem health.
• Social and economic viability: Fair wages and safe working conditions should be ensured for aquaculture workers. Moreover, local communities and small-scale farmers should be supported. 
• Climate adaptation and resilience: The industry should focus on how it can build its resilience to climate change and adapt. 

How can aquaculture be made more sustainable? 

Aquaculture plays a critical role in global food security, but its environmental impact must be carefully managed to ensure long-term sustainability. Below are key strategies for making aquaculture more sustainable.

Implement RAS

Traditional fish farming releases large amounts of waste into surrounding waters. RAS reduce this impact by recycling and filtering water within a closed-loop system. This minimises pollution and reduces water consumption. Atlantic Sapphire’s land-based salmon farms in Florida already leverage RAS to cut down on environmental impact while increasing production efficiency.

Adopt IMTA

IMTA mimics natural ecosystems by farming different species together in a way that benefits the environment. This circular approach reduces waste and increases efficiency. Some Salmon farms in Scotland and Canada have successfully leveraged IMTA to curb environmental impact while improving water quality. 

Shift to alternative and sustainable feeds

Traditional fishmeal and soy-based feeds contribute to overfishing and deforestation. Sustainable alternatives can reduce these environmental pressures. Examples of sustainable feed sources include insect-based feed, food waste and by-product feed, and algae. Ultimately, this reduces reliance on wild-caught fish for feed, lowering the carbon footprint of aquaculture operations.

Move toward offshore and deep-sea aquaculture

Coastal fish farms can degrade ecosystems through waste build-up and disease spread. Moving fish farms offshore reduces these risks. For example, Norway’s offshore salmon farms operate in deeper waters to not only decrease disease risks but also improve overall sustainability.

Expand seaweed and shellfish farming

Seaweed and shellfish farming are among the most sustainable forms of aquaculture as they require no feed, fertilisers, or fresh water. They offer a variety of benefits, from absorbing carbon dioxide and nitrogen to reduce ocean acidification, providing marine habitats to boost biodiversity, and more. There are some seaweed farms situated in New England and Scotland for these very reasons and to create sustainable food sources. 

Improve traceability and certification

Ensuring transparency and accountability in aquaculture is key to sustainability. Certification programmes and digital tracking can help prevent overfishing, pollution, and illegal fishing practices. Sustainability certifications like the MSC, ASC, and BAP ensure responsible practices. However, Blockchain technology can also be leveraged to track seafood from farm to plate to improve supply chain transparency. The Norwegian salmon industry utilises AI-powered tracking systems to monitor both fish health and feed efficiency. 

Reduce antibiotic and chemical use

Overuse of antibiotics in aquaculture leads to antibiotic resistance and environmental contamination. Some sustainable solutions include opting for vaccination and probiotics over antibiotics, AI-driven health tracking, and improved water filtration and disease monitoring systems. 

Strengthen policy and community involvement

Small-scale fish farmers often need support and guidance to transition to sustainable practices. Governments and businesses must work together to promote responsible aquaculture. For instance, through incentives and regulations, training programmes, and fair wages for workers in the industry. The EU Common Fisheries Policy (CFP) is one policy that promotes sustainable aquaculture and responsible fishing across Europe. 

Conclusion

The future of aquaculture depends on its ability to adapt and adopt more sustainable practices. Innovations in technology and responsible management are paving the way for a more sustainable seafood industry. However, Governments, businesses, and communities must work together to enforce stricter regulations, invest in research, and support small-scale fish farmers. 

Responsible aquaculture will be essential in ensuring a secure and environmentally sustainable food supply as the global population grows and pressure on wild fish stocks increases. The industry has already made strides in the right direction, but continued innovation and commitment will determine whether aquaculture can truly reach its potential.