...they live in freshwater and then
swim to the exact location where they hatched in the saltwater seas
to mate. The mature American eel looks like a snake with a long
dorsal fin and may live from five to twenty years. At about eight
years, they make an incredible journey from the Great Lakes to their
birthplace in the Sargasso Sea to spawn, a journey of thousands of
miles through the Atlantic. When they reach the Sargasso Sea, a
sluggish area filled with seaweed that lies between Bermuda and
Puerto Rico, they spawn and die. Their eggs hatch into transparent,
leaf like larvae that drift in the Gulf Stream feeding upon plankton
until they reach the Gulf of St. Lawrence, a year’s journey.
By this time they have reached a length of six inches and have
become round-bodied young eels called elvers or grass eels. From
the river’s mouth they swim in thick swarms for a thousand more
miles up the St. Lawrence River into Lake Ontario...
Read more about the species found in the Great Lakes in my book: The Dynamic Great Lakes widely available on the www and in brick and mortar stores such as Barnes & Noble and many others.