Definition
A freshwater eel is any eel that spends most of its adult life in freshwater environments like rivers, lakes, and streams. π Think of them as the eels that prefer the calmer waters inland, compared to their ocean-dwelling cousins. They often migrate to the ocean to breed (catadromous). They are important predators in freshwater ecosystems. Many species are commercially valuable. Their populations are threatened by habitat loss and overfishing.