European Eel

The European eel is a long, slender fish that looks a little like a swimming ribbon. A grown eel is usually about half a metre to two-thirds of a metre long, though a few grow much bigger — the longest ones on record reach more than 1.3 metres. Their smooth bodies bend and ripple through the water, and they have no pelvic fins, so their fins run in one soft frill along the back and belly.

European eels have one of the most amazing life stories of any animal. They begin as tiny, see-through, leaf-shaped babies in a warm part of the ocean called the Sargasso Sea. From there they drift on gentle ocean currents for about 300 days, slowly travelling all the way to the coasts and rivers of Europe.

Along the journey they change shape again and again. First they become clear little “glass eels”, then small “elvers”, and at last they grow into the darker adult eels that swim up rivers and streams. As adults they hunt at night, eating worms, insects, small crustaceans, and little fish they find along the riverbed.

After spending many years — sometimes fifteen, twenty, or even more — living happily in fresh water, the grown eels feel the pull of the sea once more. They swim thousands of kilometres back across the wide Atlantic Ocean to the very same Sargasso Sea where they were born, and there they lay their eggs so that a new group of baby eels can begin the great journey all over again.

Sadly, far fewer young eels are reaching Europe than there used to be, and the European eel is now Critically Endangered. Things like fishing, dams that block their path, and dirty water have made their long journey harder. Today many people are working to help eels by cleaning up rivers and building special ways for them to swim past dams, so these gentle travellers can keep making their wonderful trip.