How climate change threatens the economic backbone of the Pacific

The vast Pacific Ocean and the islands dotted within it produce more than half of the world's tuna.

Among the islands are 33 scattered across the centre that encompass the country of Kiribati.

Here more than 70% of government revenues come from selling tuna fishing licenses to foreign fleets - the highest proportion of any nation.

Kiribati has a tiny land mass. When all the islands are combined it is about the size of New York City. However, it has a huge swathe of territorial waters, otherwise known as its Exclusive Economic Zone (EEZ).

Totalling more than 3.4 million sq km (1.3m sq miles), the EEZ is spread across three separate parts, surrounding the country's three groups of islands - Gilbert, Phoenix and Line.

Collectively, this area is bigger than India and offers access to an ocean abundant with marine life, including skipjack, yellowfin and bigeye tuna.

AFP via Getty Images
The global tuna market is said to be worth more than $44bn a year
Yet, while the ocean is intimately linked to the culture, livelihoods and economy of Kiribati, it is also the country's biggest threat.
 
Warming water temperatures caused by climate change pose a substantial risk to local tuna populations, threatening Kiribati's economic backbone.

Scientists fear warmer waters could lead to tuna moving permanently out of its EEZ to cooler temperatures to the east, reducing the demand from overseas fleets for its fishing licenses, which would badly hit the country's economy.

The global tuna market is worth more than $44bn a year, according to one study.

To fish in Kiribati's waters, foreign fleets must first obtain a licence from the government. Then they have to pay the required fees, and follow strict rules on catch limits and reporting hauls.

The majority of these licences are sold to countries like Japan, China, the US and members of the European Union.

Kiribati generated $137m (£102m) from selling fishing licenses in 2024, government figures showed. This income is a "critical financial lifeline", says Riibeta Abeta, permanent secretary for the country's Ministry of Fisheries.

Abeta adds that such licenses contributed to almost three-quarters of government income between 2018 and 2022.

This equates to roughly two-fifths of the entirety of Kiribati's GDP, according to the International Monetary Fund.

"Next time you go into the supermarket and you look at the cans of tuna, five-and-a half cans out of 10 stacked up are coming from the Western Central Pacific Ocean [including Kiribati]," says Simon Diffey. He is a fisheries specialist with more than 30 years of experience covering Kiribati.

Diffey says the two biggest players in the region are Kiribati and Papua New Guinea. But while Papua New Guinea has the landmass and physical resources to diversify its economy, Kiribati does not.

"The highest point above sea level in Kiribati - unless you climb a coconut tree - is two metres. No water, no land, no resources other than fish."

Tuna react to small changes in water temperature to within a tenth of a degree of celsius, adds Diffey. As the surface water temperature rises in the Pacific Ocean, the tuna will migrate to cooler areas.

Numerous studies say that in the Pacific this migration will be eastwards, away from many island nations, including Kiribati.

Abeta says that the risk of international fishing ships not ne