Climate change threatens Malta’s tuna industry

Climate change could threaten Malta’s aquaculture industry by altering the Mediterranean migration routes of Atlantic bluefin tuna as early as 2030, a proposed 10-year strategy warns. 

The Action Plan for Sustainable Aquaculture 2026–2036, just issued for public consultation, warns that rising temperatures could disrupt tuna migration. It also warns that temperature changes could also increase the risks of disease, parasites and fish mortality among captive tuna. 

Malta's industry depends heavily on capturing wild tuna during their migration and fattening them in offshore cages before exporting them, principally to Japan. The industry is lucrative since the fish is prized in the Japanese market. 

In response, the government proposes expanding fish farming further offshore, diversifying into new species while still increasing production capacity. 

Tuna’s economic vulnerability 

The climate threat compounds the economic vulnerabilities of a sector heavily dependent on Japan, which accounts for 95% of Maltese tuna exports. 

In 2023, Malta produced almost 21,000 tonnes of farmed fish worth €199.1 million. Although production volumes increased by 15.4%, export revenues fell by €121.31 million, or 38%, as prices per kilogramme almost halved. 

Then-Foreign Minister Ian Borg visiting the Tokyo fish market in 2022. Japan remains the main export market for Mediterranean bluefin tuna captured by Maltese ranchers

Operating costs also increased, with intermediate consumption rising by €28.5 million to €266.8 million. Live tuna captures and imported baitfish, particularly mackerel, account for around 60% of operating costs. 

The strategy proposes research into artificial tuna feeds to reduce dependence on wild-caught baitfish. 

Farming further offshore 

The plan distinguishes between coastal aquaculture within seven nautical miles of shore and open-sea farming beyond that distance. 

The introduction of Malta’s Exclusive Economic Zone Act in 2021 has created opportunities for commercial activities further offshore even if the process of declaring the extent of the EEZ has not been finalised. 

The government is assessing potential locations for open sea fish farms and their environmental viability. Semi-submersible cages, stronger mooring systems and monitoring sensors are expected to facilitate farming in more exposed waters. 

The strategy also proposes reviewing the South-East Aquaculture Zone’s current 9,000-tonne permitted capacity to assess whether it can accommodate further production. 

Diversifying beyond tuna 

A central objective is to increase production of species bred entirely in captivity, including seabass and seabream. Research is also examining the commercial potential of greater amberjack and red porgy. 

Seaweed and shellfish farming are identified as lower-impact alternatives because they do not require artificial feed. The plan also promotes integrated multi-trophic aquaculture, combining fish farming with seaweed and shellfish to absorb excess nutrients. 

The strategy acknowledges persistent environmental disputes over oily residue, commonly known as fish slime, generated by feeding tuna with wild baitfish. Although farms were relocated further offshore in 2017, coastal slicks and dead tuna washing ashore continue to fuel public opposition. 

A survey cited in the document found that 25% of Maltese respondents viewed aquaculture negatively, while half expressed extreme concern about its environmental impact. Around 65% preferred wild-caught fish, compared with an EU average of 36%. 

New infrastructure and offshore projects 

The plan proposes Malta’s first private-sector-led hatchery for closed-cycle species, a centralised cold-storage facility and a dedicated pathology laboratory. It also proposes a National Aquaculture Council to streamline administration, with permit procedures currently taking between three and five years. 

The offshore ambitions come as a major fish farm proposed by Seaculture Ltd is undergoing environmental scrutiny. 

Located around 22km off Malta’s south-eastern coast, the project envisages four submerged cages producing between 5,000 and 8,000 tonnes of fish annually. The company is partly owned by Israel-based Dagat Hayam Holdings alongside two Maltese companies. 

In September 2025, the Environment and Resources Authority ruled that the development required a full Environmental Impact Assessment and an Appropriate Assessment, citing its location within a marine Special Protection Area and potential impacts on protected seabirds and the marine environment.