The eel colonises all the French seaboards. It can be found in the Mediterranean Sea, the Bay of Biscay, the Celtic Sea and the English Channel. It colonises a wide range of environments: bays, ponds and coastal basins, estuaries, rivers and lakes. It is a very robust species that can adapt very quickly to environments of very different salinities: fresh, brackish or salt water. In the past, it was very abundant in our fresh and brackish waters and was caught at different stages of its life cycle and was a very popular fish in many communities. Fishermen have developed a wide variety of fishing methods to catch them: hand, pushed or anchored sieves for glass-eels; lines, ropes, nets, fyke nets, trap nets for yellow and silver eels (see “Our gear and practices” tab). These, through their adaptations to the aquatic systems explored and the biological stages exploited, constitute a real heritage of the fishing culture of our rural territories which must be preserved. This heritage also allows us to better understand the distribution of the species, its abundance and its characteristics in environments that are little investigated by research teams whose classic prospection tools (electro-fishing or traps) can only correctly inventory environments of limited ecological diversity.