Migration 



same river in which they were brought up, despite the 

 fact that they wander for considerable distances from the 

 mouth of their home river during their life at sea. 



Interesting as is the migration of salmon, that of the 

 common eel is far more so, and it is only in comparatively 

 recent years that it has been fully understood. In fact, 

 not so very long ago young eels were considered as quite 

 a distinct and peculiar kind of fish and were not associated 

 with eels at all. There has always been something akin 

 to mystery surrounding the life history of the eel. 

 Aristotle gave it as his opinion that eels were formed 

 from mud. A belief which still holds sway in some parts 

 of the country was once widespread namely, that horse- 

 hair falling into the water would grow into eels. 



For many years all that was known of this very common 

 fish was that young eels or elvers migrated from the sea 

 to the rivers in spring, and that silver eels, as the mature 

 fish are called, migrated seawards in autumn. It has now 

 been firmly established that eels spawn in mid-ocean ; 

 from their eggs arise curious leaf-like little fish, so frail 

 and transparent that only their eyes are visible as they 

 swim in the water and so unlike their parents that they 

 were called Leptocephali. These tiny creatures are quite 

 unable to battle with the waves, so they simply drift 

 upon the Gulf Stream till they are carried towards the 

 coasts of the Atlantic. When they drift to shallower 

 water they change from Leptocephali to elvers. 



At the mouths of the rivers they dwell for a time and 

 collect in vast crowds ; when their numbers are sufficient 

 the vast army migrates from the sea to the upper reaches 

 of the rivers, travelling mostly at night, unless there be a 

 full moon, when the migration is hindered, for light seems 

 distasteful to the little voyagers. In fact, the eel is of 

 somewhat nocturnal habits ; even the adults feed, for the 

 most part, by night. Several years are spent in the 

 rivers before the eels are ready to migrate to the sea for 

 spawning. When that time arrives they change in 



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