Far away in the middle of the Atlantic Ocean is a sea called the Sargasso Sea. It is a gigantic clockwork of currents called a gyre, where millions of American and European eels are born every year. Over one hundred species of fish, snails, crabs, turtles, and eels make their homes and are born in the mats of seaweed called sargassum. These mats of seaweed can stretch for miles.
The baby eels, called larvae, ride the ocean currents till they reach North America and Europe, sometimes taking up to a year to arrive on the American shores. American and European eels are genetically different.Now one of nature’s most incredible transformations begins. The skin and internal organs of the eels change in order to adapt to living in fresh water after living in salt water.Following the larva stage, the eels become glass eels. They are now 2-3 inches (5-7.5 cm) long with elongated bodies, prominent black eyes, and developed fins.
They are between seven and twelve months old when they reach coastal water.Glass eels then turn into elvers. They grow several more inches and develop pigmentation, becoming dark gray, and form a thick and slippery mucous layer. If you try to pick one up, you will learn they are as slippery as an eel!The elver stage is followed by the juvenile or yellow eel stage, and finally by the silver or mature adult eel, which can reach lengths of 2-5 feet (.6-1.5 m) Their coloration can vary.The American eel usually hunts at night. During the day, it hides in gravel, sand, masses of plants, or other forms of shelter. In the winter, eels burrow under mud and enter a state of torpor, or inactivity. However, they may become active at times.
These eels can travel up to 4,000 miles (6,400 km) in a lifetime. American eels can live up to thirty years, and, at the end of their life, they swim back to the Sargasso Sea. Some scientists believe the Earth’s magnetic field helps eels find their way back home. Once again their bodies undergo dramatic changes. They stop eating; their skin thickens; their eye size doubles, improving their vision in deep, dark water; and their pectoral fins enlarge for the long swim back.
After months of travel, they produce new offspring. These larvae will begin their life’s journey. The adult eels’ work is done.Now that is one fantastic voyage.