The subject of where eels go to mate has recently been discussed by New Scientist magazine in the form of an interview with Danish scientist Johannes Schmidt.
Schmidt explains the general scientific consensus is that both American and European eels embark on a journey over thousands of kilometres across the ocean to spawn. The prime location is the Sargasso sea. Sargasso sea is a region in the gyre in the middle of the North Atlantic Ocean. One remarkable fact is that it’s the only sea on Earth which has no coastline. The sea is named after the Sargassum seaweed that gives the water a brownish color.
A whole variety of eels makes the journey from Greenland down to South America. For migrating eels, the water is warmer and saltier than the surroundings. After being bred, it is thought the newly spawned baby eels (or elvers) then make the long journey home.
Of the two eels, the European eel (Anguilla anguilla) grows to around 1.5 meters in length; the American eel (Anguilla rostrata), is a little shorter, at around 1.2 meters long.
The migratory path of the eel is based on assumption, according to Schmidt. This is based on predicted patterns for no adult eels have ever been found spawning in the Sargasso sea, although small, transparent eel larvae have been found in the sea. Moreover, until very recently, no eels had even been seen en route. For the tiny elvers, the journey back is thought to be through the drifting motion of ocean current and this journey can take up to 300 days.
For now, the mating and breeding patterns of thousands of eels remain a mystery.
