Fishing and Aquaculture in a Changing Climate: Challenges and Perspectives
The fisheries and marine aquaculture sectors are on the front lines of climate change. The IPCC warns: “warming, ocean acidification, and business-as-usual fishing policy […] are projected to place around 60% of global fisheries at very high risk.” Yet, these sectors provide jobs and income, while aquatic resources are essential for global food security. Fishing has historically been the primary source of marine animal production, but over the past fifty years, it has also become the most harmful human activity for marine biodiversity (IPBES). Since 2022, aquaculture has surpassed fishing in terms of marine food supply, but this rapid growth, coupled with unsustainable practices, has also had significant impacts on ecosystems. In conditions of changing climate, it is therefore crucial to ensure the transition of fishing and aquaculture practices towards a virtuous model, one that is more sustainable for marine life and desirable for the societies that depend on them.
In response to this urgency, the Ocean & Climate Platform and its members are publishing “Fishing and Aquaculture in a Changing Climate: Challenges and Perspectives”.
Climate change, fisheries, and aquaculture: combined and cascading impacts on marine ecosystems
Under the combined effects of climate change, fishing, and aquaculture, marine ecosystems are facing unprecedented pressures. Rising temperatures, ocean acidification, and deoxygenation are compounding the severe impacts of stock overexploitation, making these environments and the associated sectors increasingly vulnerable.
The use of non-selective and harmful fishing gear for seabeds, the degradation of coastal ecosystems, and the introduction of pollutants, pathogens, and invasive alien species through aquaculture are still too often linked to current practices in these sectors.
The consequences extend beyond fish species to their habitats and, through trophic networks, affect all living organisms in the sea and on land. Over the past few decades, global species abundance has significantly declined. In parallel, fish populations are undergoing radical shifts in distribution, their size is decreasing, and biodiversity continues to erode.
© Natacha Bigan
Fishing now faces a paradox: as coastal resources decline, the sector has intensified its technical capacities and has expanded operations into the high-seas and in deeper waters, targeting stocks that continue to dwindle. Although aquaculture has seen strong growth since the 1990s, it is not immune to frequent climate shocks. It also relies on wild-caught fish for feeding marine finfish farms which use fishmeal and fish oil derived from marine organisms like krill.
Varying impacts across the globe
On a global scale the pressures exerted by climate change and fishing on biodiversity and ecosystems are changing and vary from one region to another. The effects of climate change intensify with increasing greenhouse gas emissions, while fishing continues to exert significant pressures on marine ecosystems. Certain populations, particularly those that directly depend on marine resources for their food, are particularly vulnerable to these shifts.
© Natacha Bigan
Human societies on the front line
Ultimately, human societies, their economies, and their livelihoods are disrupted. Fishing and aquaculture have already experienced significant economic shocks due to extreme climate events. According to the IPCC, losses in fishing revenue could reach $15 billion by 2050 compared to 2000 if greenhouse gas emissions continue to rise.
Coastal communities and those directly depending on these activities for their livelihoods and food are on the front lines. The growing instability of fishing and marine aquaculture participate in making working conditions even more precarious while these sectors are already among the most dangerous in the world, according to the International Labour Organization. For developing countries, particularly island nations and territories, as well as indigenous communities, the decline of marine resources poses a serious threat to health and food security. In 2017, fishery resources accounted for 50% of their animal protein intake.
The decline of small-scale fisheries disrupts entire local fabrics and leads to heatened conflicts. As climate change drives a global redistribution of fish stocks and significant fluctuations in their abundance, conflicts over resource sharing can emerge. Tensions over mackerel catch quotas in Europe is a striking example of this.
Reversing the trend: adapting fishing and aquaculture sectors
Adapting the fishing and aquaculture sectors to global changes is both essential and inevitable.
© Natacha Bigan
Adaptation solutions must center ecosystems. Strengthening and expanding Marine Protected Areas, using more selective and less impactful fishing gear are key avenues for developing an ecosystem-based approach to fisheries. Additionally, promoting integrated multi-trophic aquaculture can enhance the efficiency of these systems while reducing pressures on ecosystems.
While technical solutions exist, they alone cannot resolve current issues. To ensure a sustainable transition, the sectors must engage profound societal and institutional transformations, backed by science, local and indigenous knowledge, and based on inclusive governance, and strengthened cooperation. Adapting fishing and aquaculture is not just a necessity; it presents an opportunity to collectively build a more sustainable and desirable future for climate, biodiversity, and human societies.
About the publication
Aimed at policymakers and the general public, this publication seeks to enhance understanding of the scientific knowledge on the interplay between the ocean, climate, and biodiversity. It addresses a critical theme at the crossroads of these issues: the transformation of fisheries and aquaculture in response to climate change.
Developed in collaboration with the OCP’s scientific network and science communication experts, the publication breaks down key findings from major scientific reports (IPCC, IPBES, FAO, WOA2). It examines the combined impacts of climate change, fishing, and aquaculture on marine ecosystems and human societies, while highlighting adaptation pathways to ensure a resilient and sustainable future for these sectors.
Authors of the article: Maud Chevalier, Anaïs Deprez, Sarah Palazot.