The European eel Anguilla anguilla, a sleek, snake-like fish with a fascinating life cycle, once teemed in rivers. But their numbers have plummeted by more than 95% since the 1980s. The European eel Anguilla anguilla, a sleek, snake-like fish with a fascinating life cycle, once teemed in rivers. But their numbers have plummeted by more than 95% since the 1980s. Ecology Biotechnology Phys.org – latest science and technology news stories