•  Ocean warming and illegal fishing are shrinking fish stocks that millions rely on in West Africa.

•  Catches of small pelagic fish have dropped sharply in Ghana and Côte d’Ivoire since the 1990s.

• A Harvard report calls for job training and economic alternatives to protect fishing communities.

Coastal fishing communities in West Africa are facing a serious crisis. A new report from Harvard University’s Salata Institute for Climate and Sustainability warns that rising ocean temperatures and illegal fishing by foreign industrial vessels, especially Chinese trawlers, are threatening livelihoods across the region.

The report, titled “Fishers on the Gulf of Guinea: Climate, and the Income Diversification Imperative,” shows how fishers along the Gulf of Guinea are already under heavy economic strain as key fish stocks disappear.

Fishers are seeing fewer and fewer small pelagic fish, a vital source of food and income in the region. Ghana’s total catch of these fish dropped by 59% between 1993 and 2019. In Côte d’Ivoire, the decline was nearly 40% from 2003 to 2020.

The trend has grown worse since the 1990s. The reason: warming oceans. As greenhouse gas emissions rise, oceans absorb most of the heat. This weakens marine ecosystems by reducing oxygen and food sources for fish.

Warmer sea temperatures are also pushing fish populations away from the coast. One of the most targeted species, Sardinella aurita, has shifted its habitat by an average of 181 kilometers per decade since 1995. Three other pelagic species are migrating even farther, close to 200 kilometers per decade.

According to the United Nations Food and Agriculture Organization (FAO), sea temperatures in the Gulf of Guinea could rise by as much as 3°C by 2099 if emissions remain high. Even under a moderate scenario, a 1.6°C increase is still likely.

The problem does not end with climate change. Large industrial fishing vessels, mainly owned by Chinese companies, are worsening the crisis. These ships often violate no-fishing zones set aside for local communities. They use bottom trawling, a destructive method that destroys everything in its path.

Although China reports having 2,600 deep-sea fishing vessels, independent studies suggest the real number is closer to 17,000 worldwide. Meanwhile, traditional fishing fleets are also growing, adding to the pressure on already stressed fish stocks.

The report makes it clear: even if illegal fishing were controlled, ocean warming alone would continue to drive fish populations down for decades to come.

Governments in Ghana and Côte d’Ivoire have tried to respond. Since 2016, they have imposed seasonal bans on both industrial trawlers and traditional canoes to allow fish stocks to recover. But these temporary closures have failed to reverse the decline in small pelagic fish or improve the situation for local fishers.

In July 2023, researchers from Harvard and local partner universities surveyed coastal communities in Ghana, Côte d’Ivoire, and Nigeria. The findings were striking. In Ghana, 90% of people said they believe their children will not be able to depend on fishing or related trades in the future. In Côte d’Ivoire, the figure was 85%, and in Nigeria, 66%. When asked about other job paths, most respondents pointed to skilled work in trades like carpentry or tailoring as the most realistic option.

Some fishing families are not waiting. In Ghana, a USAID survey found that 73% of coastal fishers reported community members already earning money from non-fishing jobs. To support this shift, a joint program by the Ghanaian government and USAID, the Ghana Fisheries Recovery Activity (GFRA), is training young people from fishing families. By February 2025, 5,250 youth between the ages of 15 and 35 had received vocational training in fields like baking, cooking, carpentry, cosmetology, tiling, and masonry.

The Harvard report urges West African governments to take two paths: better short-term fishery management and long-term investment in income alternatives. It calls vocational training a top priority.

Still, funding is a major barrier. The estimated cost to train one person is $400, a steep price for countries with limited budgets. The report calls for more support from international partners and smarter use of local resources.

Walid Kéfi