The results are in line with previous years. In France, the share of fish caught “under sustainable conditions” remains at more than 50%. This is progress compared to the situation twenty years ago (with only 18%).
The Mediterranean is less well off, because only 36% of the species fished there are “sustainably exploited”. Far below the European objective of fishing for 100% species in good condition (1).
In its 2023 report on “fish landed”the Ifremer research institute establishes that “overfishing affects 20% of volumes”mainly Atlantic mackerel and sardines, “overfished and degraded”, (from the Bay of Biscay to the North Sea).
Critical species
Ifremer 2024 infographic J. Barrault.
The situation is even more critical for two very common species: pollack (Celtic Sea, Channel and North Sea) and hake (Mediterranean).
Despite a management plan initiated a few years ago, “the biomass does not rise above the threshold limits”deciphers Clara Ulrich, coordinator of fisheries expertise at Ifremer.
“When we talk regarding a collapsed population, this does not mean extinct or disappeared, but that the number of males is too low to ensure the renewal of populations, enlightens the scientist. This represents a biological risk. But also an economic risk for fishing.”
When there is “fewer fish in the sea means fewer fish available for fishing, a situation that no one wants, neither fishermen nor consumers..
The hazard of renewal is even greater in the Mediterranean, where red mullet is “the only population [pêchée et évaluée] in good condition”. Bluefin tuna, which represents a third of the fish caught, is considered “reconstituable”.
This table is not complete, because more than half of the species landed in the Mediterranean are not assessed, such as sea bream, mackerel or octopus. “There is a lot of scientific work underway, but it still does not provide a diagnosis”.
Studying young fish
At Ifremer, the renewal of young fish has become a subject of study in its own right. “This becomes an issue because variability increases. A few bad years can be enough to cause significant reductions in biomass in subsequent years.”
In particular, scientists observe that the impacts of climate change bring “greater uncertainties regarding the renewal of fish populations”.
An example is “the time lag between the moment when the larvae hatch and when they find their food. Climate change is disrupting this synchronization between fish and plankton”.
For the Mediterranean, the unfavorable factors are accumulating. “Not only is there climate change, but also pollution and destruction of coastal habitats.”
Questions regarding the contribution of rivers
Ifremer also describes a recent phenomenon, which is still only an observation: “The contributions of the rivers have changed. The nutritional power of the water has changed. The water of the Mediterranean has become a little poorer.” Is it linked to climate change or more direct human factors?
“Rather than climatic, the change is global, continues Clara Ulrich. When the climate changes, a lot of things change besides the climate. Invasive species are arriving that weren’t there before, diseases that weren’t there before. Pollutants present. A number of factors come into play at the same time.”
It is all of these interactions that we must try to understand.
1. Maximum sustainable yield, set by the Common Fisheries Policy.
