This paper, authored by Dr Brett Glencross, was originally published in the July edition of International Aquafeed

The simple act of choosing what to eat carries weight far beyond personal taste and nutritional value. In an era defined by a looming climate crisis and the degradation of our natural world, our dietary decisions are increasingly entangled with the health of the planet. Nowhere is this connection more critical, and often more opaque, than in the realm of seafood production. Ignoring the importance of sustainability and the environmental footprint in this vital food sector is no longer an option; it is critical for long-term food security.

The urgency stems from the undeniable impact of our current food systems. Agriculture, in its broadest sense, is a significant contributor to greenhouse gas emissions, land degradation, water scarcity, and biodiversity loss. While terrestrial farming rightly receives most of the attention in these discussions, the aquatic realm also presents a unique set of challenges and equally pressing concerns. Our growing appetite for seafood has promoted an industry that, without rigorous attention to sustainability and carbon footprint, may decimate oceanic ecosystems and exacerbate climate change.  

The use of carbon footprint analysis provides a critical lens through which to understand the true cost of our food. It meticulously tracks the emissions associated with every stage of a product’s lifecycle, from the energy used in farming or fishing to transportation, processing, packaging, and even disposal. Through applying this methodology to food production, it can reveal the hidden environmental burdens of our choices. For instance, conventionally farmed beef often carries a significantly higher carbon footprint than fishing and aquaculture produce due to methane emissions from the livestock and the land use changes associated with pasture. Similarly, different methods of fishing and aquaculture also have vastly different carbon intensities.

In the context of fish sourcing, a carbon footprint analysis can also illuminate the contrasts between various options. Consider the energy-intensive practice of bottom trawling, where large nets are dragged across the seabed. This method often has a considerably higher carbon footprint compared to more selective and less energy intensive fishing techniques like purse seine fishing for small-pelagic fish. Similarly, the transportation of seafood across vast distances, often involving refrigerated air freight to maintain freshness, adds significantly to its carbon footprint. Alternatively transporting materials in bulk by sea freight is remarkably efficient in comparison. This also highlights the effects of scale, with large scale activities often having lower footprints due to their higher yields relative to impacts.

Aquaculture has been touted as a solution to avoiding overfishing, though it presents its own complex web of sustainability and carbon footprint considerations. While it can alleviate pressure on wild stocks, poorly managed aquaculture can lead to habitat destruction, localised pollution from fish waste and chemicals, and the potential spread of diseases to wild populations. Furthermore, the feed used in aquaculture, mostly made these days from agricultural crop products, has been shown to be a major part of the carbon footprint of aquaculture. While the feed used to be largely derived from wild-caught fish products, marine ingredient inclusion now represents less than 10% of the ingredient resource use globally. However, continued development of alternative feed sources like algae oils or by-product marine ingredients, is still needed and offer pathways towards lower carbon and more environmentally sound practices.  

The importance of informed consumer choices cannot be overstated. By understanding the principles of sustainability and the implications of a products carbon footprint, individuals can become powerful agents of change. Choosing fish that is certified by reputable organizations like MarinTrust, the Marine Stewardship Council (MSC) or the Aquaculture Stewardship Council (ASC) indicates that the product meets rigorous environmental, social and traceability standards. Reducing seafood waste through careful planning and proper storage also contributes to a more sustainable seafood system. Additionally ensuring that we use all the fish; the head, the frame, the guts, as well as the meat can help maximise its value to our food system, as well as its return the fishers who catch it.

The food industry itself has a significant role to play in driving sustainability. Restaurants and retailers can prioritize sourcing sustainable seafood and transparently communicating their sourcing practices to consumers. Investing in supply chain traceability and working with fishers and aquaculture producers to adopt more sustainable methods are crucial steps. Education of the seafood sector and its downstream supply chain in the sustainability stories is crucial. In many cases seafood offers a better sustainability story than most imagine, with seafood choices being amongst the most sustainable animal protein sources the world produces.  

Ignoring the interconnectedness of our food choices, the health of our planet, and the future of our food security is a dangerous gamble. The ocean, a vital carbon sink and source of food for billions, is under increasing stress. By embracing the principles of sustainability and diligently analysing the carbon footprint of our food, particularly the fish we consume, we can begin to steer the unseen tide towards a more resilient and environmentally responsible food system.