On 28 October 2022, the GFCM (General Fisheries Commission for the Mediterranean) presented the eel research and assessment program in the Mediterranean Sea by videoconference. Nearly 130 participants took part in this webinar: “Involving scientists and fishermen in the process of data collection and management of European eel in the Mediterranean”.

This research program focused on lagoon ecosystems: ecosystems where data are less scarce and where eel fishing has developed in the Mediterranean. These studies do not take into account river ecosystems and interfaces between the catchment area and the sea, although these ecosystems are very likely to be important production areas for eels: Rhone, Ebro, Medjerda, Po, Nile, etc…

The results of the computations carried out by modelling the data available, modelling processes that are not detailed in this forum, appear to be inconsistent on several points:

1 – Effect of restocking on all sites (at density of 1g/ha) – 3.2% increase in escapement in 2030. The problem with this estimate is the use of a density of 3 glass eels per hectare, which is totally inefficient. On the scale of the French Mediterranean lagoons, this would mean 58 kg of glass eels to be immersed.  For Lake Aureilhan in New Aquitania, the density used is 1800 glass eels per hectare.
2- Restoration of ecological continuity – 0.4% increase in escapement (quantity of silver eels) in 2030. In a nutshell, this is a very bad signal to those who are building barriers everywhere and will continue to do so in the Mediterranean countries which are under stress with regard to their water supplies. The working group specified that this only applied to lagoons. This is true, but by leaving this type of document lying around when it is not very well specified in the report, there is a risk of misinterpreting a pressure factor that is crucial for the future of the eel.
3 – Total ban on fishing – 109.7% increase in escapement in 2030. This needs to be checked, however, because as things stand at present and with the data we have on exploitation rates in the Mediterranean lagoons, only 20% of the escapement would actually be “saved”, which would also be diluted across the range, with the resulting recruitment completely dispersed from Mauritania to Norway. In short, and to be very clear: to see an effect of this measure 3 years after the ban on fishing (advised by the research group to evaluate the measure) is illusory and will lead to the total ban on fishing being renewed. It would be better to warn the companies affected immediately, as they will clearly be affected for nothing, whereas glass eels often accumulate at the foot of obstacles built at the mouths of rivers.
For example, the Rhône, where there has never been any glass-eel fishing at the mouth, and where professional eel fishing has been residual for 15 years, is not seeing any improvement in its situation, according to the french administration and the French Office for Biodiversity.

Like the International Council for the Exploration of the Sea (ICES), the GFCM does not place eel management in the more general framework of water management and habitat restoration, a framework that has deteriorated considerably and which must be placed for the Mediterranean in the broader framework of the Mediterranean Action Plan (MAP) and the Blue Plan. 

Many participants insisted on this point and asked that the rational management of water and the restoration of habitats be a prerequisite for any additional constraints on fishing activity. The future of the eel is at stake, as well as a more ecological management of our aquatic ecosystems in a development framework that is only sustainable in name.