Overfishing is declining in Europe, but progress is “uneven from region to region”, according to a new evaluation.

The European objective of 100 per cent sustainable fishing by 2020 has “not been reached” and climate change is “inevitably” affecting fish distribution and growth, the study released by French research agency Ifremer says.

Ireland’s Marine Institute worked with Ifremer, along with the French higher education and research agency L’Institut Agro, and the Flanders research institute for agriculture, fisheries and food (ILVO) on the study into the status of fish populations in 2022.

The evaluation says that the 2022 report from the Scientific, Technical and Economic Committee for Fisheries (STECF) on the health status of fish in Europe “confirms the trends observed in the Atlantic over the past 20 years: overfishing is falling”.

It has found that 72% of fish populations are "not overexploited" in the north-east Atlantic area.

“Fish biomass has been increasing continuously since 2007 and was 33% greater in 2020 than at the beginning of the 2000s for the best-tracked populations; it was more than 50% greater for other populations subject to less tracking,”it says.

It says that 86 per cent of fish populations are overexploited in the Mediterranean, where the situation remains “critical”. In total, 29 of the 34 fish populations evaluated are considered to be overexploited, while “many other species remain poorly tracked and understood”.

It says that climate change is having direct impact on marine biodiversity, as it “changes species distribution, reduces their available food and stunts their growth”.

“Each year, the ocean absorbs between 30% and 40% of the CO2 that human activity releases into the atmosphere. This excess CO2 causes ocean acidification, which weakens the water’s concentration of calcium carbonate,” the study says.

“Calcium carbonate is essential for plankton, corals, molluscs and many other calcifying marine organisms that use it to build their shells or internal skeletons,” it notes.

Carbon dioxide also increases water temperature, reducing available oxygen and decreasing plankton abundance.

“Using climate models created by the Intergovernmental Panel on Climate Change, scientists have established that by the end of the century, marine animal biomass could have decreased by 20% on average,” the study says.

The study says that scientists are taking an ecosystem-based approach, allowing them to “propose management scenarios that better account for all ecosystem changes, not just the direct consequences of fishing”.

“ Scientists are also working on more technological aspects of fisheries management, like the development of more precise fishing methods. One idea is smart trawl nets that combine cameras and artificial intelligence to open and close depending on the species targeted,” it says.

Fostering more resilient ecosystems and encouraging good fisheries management are top priorities, the study says.

Ifremer, in partnership with the Marine Institute and others, will hold its fourth annual press conference on the status of European fisheries next Tuesday 24 May at 10am CEST (9am IST).

The conference will address the following topics:

• Possible solutions for the future of the Common Fisheries Policy. How can fisheries contribute to a healthy marine ecosystem? With David Reid (Marine Institute)
• How do European scientists monitor and assess the status of fish populations? The importance of European coordination of oceanographic campaigns, Els Torrele (ILVO)
• How are the fish in the European Union? CSTEP report 2021 ‘CFP monitoring results’, Clara Ulrich (Ifremer)
• The consequences of climate change on fisheries resources and fishing. ‘Exploitable’ biomass decline, fish populations displacement, instability, and unexpected events, Didier Gascuel (Agro Campus Ouest)

To watch the conference live, sign up at [email protected]