Prof Hilge about
Biology and population development of the European eel
The European eelAnguilla anguilla, is native to the North Atlantic with the North Sea and Baltic Sea and many waters of the European continent from southern Norway to the Mediterranean and North Africa. It is therefore found in both fresh and salt water. The adults spawn in an area in the Sargasso Sea in the south-western North Atlantic that can only be roughly defined by larval catches. Fecundity is around 2 million eggs/kg body weight. The juvenile stages, starting from the freshly hatched, barely 2 mm large larva to the willow leaf larva, finally reach the European coasts as glass eels after a migration of 5 - 6,000 km with the help of the Gulf Stream after about 3 years and then ascend into the flowing waters.
Depending on the latitude, the European eel remains there for around 6 - 12 years or even significantly longer, with shorter residence times towards the south. During this time, they feed on crustaceans and small fish as well as worms and insects. The fat content of the growing eels increases over the years to 25 - 30 % of the body mass. This energy storage is the prerequisite for a successful return migration through the Atlantic to the Sargasso Sea. It begins after the transformation to silver eel, recognisable by the enlargement of the eyes and pectoral fins.
No more food is consumed during this time. Maturation begins at the latest in the final phase of the 5 - 6 month migration, which is completed in March/April by spawning. Some of the life cycle of an eel briefly outlined here is questionable and still eludes our exact knowledge.
On the decline in the eel population
There are various possible reasons for the decline in eel populations. These include environmental pollution, habitat loss, transverse structures and hydropower utilisation in flowing waters, parasites or predators (cormorants) as well as a decline in stocking and the removal of glass eel from the natural cycle, export to Asia, aquaculture facilities and direct consumption combined with an increase in demand and, furthermore, a price explosion from 80 €/kg glass eel (1990) to over 1,000 €/kg glass eel (2005). Added to this is the presumed importance of climate change with its effects on weather conditions in the North Atlantic with regard to the migration success of eel larvae. This applies in particular to surface water temperatures and current conditions in those areas that are important for the eel, especially in the reproduction and larval phase.
Artificial reproduction of eels is still not possible today!
This makes it all the more necessary to use a sufficiently large proportion of the elvers arriving on the European coasts for Stocking programmes in inland waters to increase the stock.
More information
Eelforever campaign
A journey through the world of eel. "Eelforever" is the name of the IFEA's web and social media campaign, which we use to keep people up to date on the important relationships and current developments in eel.
About the ESA
The Eel Stewardship Association (ESA) is the founder of the Eel Stewardship Fund and owner of the ESF trademark.
About the ESF
In 2016, the IFEA launched the ESF (Eel Stewardship Fund) with the ESA. For every eel sold with this logo, a fixed amount is paid into the ESF, which is used to finance measures to restore the eel.
To the homepage
Here is an overview of the activities of the Eel Initiative.