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Eel Migration. Life Cycle: When born in the Sargasso Sea the larva drift with the currents until they are about 2 weeks old After the eels reach two weeks of age they can start their migration.
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Life Cycle: • When born in the Sargasso Sea the larva drift with the currents until they are about 2 weeks old • After the eels reach two weeks of age they can start their migration. • Usual age is two weeks-three years, where they will travel to different locations around the worls, finding suitable streams. • Once they have found a suitable stream, they turn into ‘glass eels’.
‘Glass eels’ • Once they have turned into ‘glass eels’ they enter freshwater. • They then travel upstream, and begin to change colour at the same time. • Once upstream they change into ‘brown eels’ or ‘yellow eels’. A yellow eel
Brown / yellow eels • The females tend to travel further upstream than the males. • At this point the eels will stay in the river / stream for about two to two and a half years if male, and nine to sixteen years if female. • Once the eels turn silver it is a signal for them to travel back to their spawning ground in the sargasso sea (located between Bermuda & puerto rico). • They then spawn, and die.
Trigger of migration • migration occurs on a few nights during each autumn. • Generally it occurs when the water temperature drops below eleven degrees. • Rainfall and water flow are also suspected of being key factors in triggering migration.
Extra eel information: • The females will carry up to ten million eggs with them on their return journey to the sargasso sea. • The journey takes twelve months, and they swim at a speed varying from 1-5 miles per hour. • They spawn deep in the sargasso sea, where it is thick with weed; this information HAS ONLY JUST BEEN DISCOVERED.