Climate Change Transforming the Ocean: Can Seafood Giants Protect Our Food Supply?

The study finds growing attention to emissions targets, with much less attention to adapting seafood production to changing ocean conditions.

The seafood on a dinner plate depends on an ocean that is becoming harder to predict, with rising temperatures changing where fish live and whether farms can keep them alive. Those changes reach fishing crews, processing workers, coastal communities and businesses whose income depends on reliable catches. Cutting emissions matters, but companies also need to prepare for damage already reaching their operations.

The research paper "Mobilizing the seafood industry for climate action," published in npj Ocean Sustainability, examines how large seafood companies are responding to this pressure. Robert Blasiak and his colleagues bring together climate projections, economic estimates and a review of corporate reporting in a Perspective article. The study finds growing attention to emissions targets, with much less attention to adapting seafood production to changing ocean conditions.

Large companies influence the seafood system through the fish they buy, the suppliers they choose and the investments they make. Small-scale operations account for around 90% of employment in marine fisheries and roughly 40% of global catch, connecting corporate decisions to millions of livelihoods. The authors argue that preparing the industry for climate change should strengthen this wider network, including people with limited access to finance, insurance and useful forecasts.

A changing ocean puts catches and livelihoods at risk

Ocean warming is only one part of the problem, alongside increasing acidity, declining oxygen, changing currents and rising seas. These pressures can disrupt food webs, damage infrastructure, increase disease risks and make existing fish-farming locations less suitable. Marine heatwaves, harmful algal blooms and storms can turn gradual environmental changes into sudden losses.

An earlier analysis cited in the paper examined 235 marine fish populations and estimated that climate change reduced their maximum sustainable yield by an average of 4.1% between 1930 and 2010. That measure describes the catch a population can support over time, with declines of 15–35% recorded in several regions. Future projections suggest global fish biomass could fall by 5.3–6.9% by 2050, depending on the emissions pathway.

By 2100, the projected biomass decline ranges from 6.7% under low emissions to 21% under high emissions. The researchers estimate that industrial catches could fall by 24% under the high-emissions scenario, equivalent to about $19 billion in current landed value, the value of fish when brought ashore. This is an illustration of economic exposure based on assumptions about future conditions and industrial fishing's share, rather than a forecast of individual company losses.

Kiribati, Micronesia, Seychelles, Tuvalu and Vanuatu, whose economies depend heavily on fisheries exports, face average catch declines of 32% by century's end under high emissions. Fish moving across national boundaries create another difficulty because fishing agreements can break down when governments disagree over access. The resulting uncertainty can encourage overfishing and threaten supplies for processors, feed manufacturers and retailers.

Climate pledges leave important questions unanswered

The researchers' August 2025 review found that 45 of the world's 100 largest seafood companies made no climate disclosures. Forty of those companies were privately owned, placing them outside stock-exchange reporting requirements. Public reporting offers a window into corporate priorities, but silence does not prove that nothing is happening, and a detailed report does not prove effective action.

Among the 30 largest companies, the number with public emissions-reduction targets rose from four in 2016 to 18 at the time of the researchers' assessment. Ten of those targets had received approval from the Science Based Targets initiative. Reporting has expanded from general environmental promises to measurements covering company operations, purchased energy and wider supply chains.

The researchers identify three recurring messages in corporate reports: responsibility for cutting emissions, opportunities to market seafood as a climate solution, and recognition of climate-related business risks. Claims about seafood's smaller carbon footprint need care because impacts vary greatly between species and production methods, with aquaculture requiring no added feed generally producing the lowest footprints. Carbon figures alone cannot explain the full environmental cost of seafood or show whether a business can cope with warmer waters.

Government decisions can strengthen or weaken progress

Japan provides an example of reporting rules encouraging greater transparency, according to the paper's account of expanded disclosure expectations. Of the 31 major seafood companies preparing or providing reports aligned with the Task Force on Climate-related Financial Disclosures framework, 16 were Japanese. Such frameworks help companies examine physical damage, risks from the shift to a lower-carbon economy, and the implications for business planning.

The paper describes European reporting and due-diligence efforts facing delays and political pressure, illustrating how government decisions can slow corporate accountability. In the Northeast Atlantic, disagreements over shared mackerel, herring and blue whiting stocks have contributed to excessive catches and lost sustainability certification. A supply-chain coalition of more than 50 companies has pressed governments for agreements grounded in scientific advice, with members pledging to stop sourcing from affected fisheries if failures continue.

Companies can pool expertise on shared problems without coordinating prices or dividing markets. Voluntary cooperation still needs scrutiny because public promises can become greenwashing when there is little evidence of changes in practice. Governments, investors, scientists and civil society all have a role in checking progress and making responsible behaviour an enforceable expectation.

Four priorities for protecting seafood's future

The researchers propose connecting climate forecasts to the financial decisions businesses make over months and years. Companies need information detailed enough to guide investments, sourcing and operational planning, supported by practical measures such as early warnings, safer vessels and suitable aquaculture species. Keeping forecasts publicly accessible would help smaller producers and governments prepare without depending on information controlled by large firms.

Tracking how climate action spreads through the industry is another priority because major buyers can influence suppliers and competitors. Researchers need to establish whether corporate commitments lead to changes across supply chains and whether those expectations exclude businesses with fewer resources. Leadership becomes more useful when its effects can be checked beyond the company making the announcement.

Examining unintended harm, including the possibility that companies move fishing pressure into less affected waters and overexploit new stocks. Exclusive access to forecasts could help powerful businesses secure fishing rights or relocate facilities, leaving workers and coastal communities to absorb the losses. Adaptation should be judged partly by who gains protection and who inherits the risk.

Sustained collaboration involving scientists, companies, governments, workers, suppliers and coastal communities. Shared efforts need transparent decisions, clear accountability and attention to whose knowledge shapes the response. For people who depend on seafood for food or income, meaningful progress means healthier fisheries, dependable livelihoods and preparation that reaches beyond corporate reports.