EEL FAMILY (Anguillidae) 



American Eel 

 Anguilla rostrala (LeSueur) 



The American eel lias one of the most interesting life histories of 

 all fishes. It is generally distributed throughout eastern North America, 

 and is easily distinguished from other fishes with the possible exception 

 of the lamprey eel. However, the American eel possesses a true mouth 

 with jaws and the lamprey has the jawless sucking disc. 



The spawning migration of the freshwater American eel has at- 

 tracted attention of natural historians for many years as one of the most 

 unusual of natural phenomena. Most fishermen have observed the fall 

 downstream migration of eels, particularly obvious in fishways. Again 

 in the spring of each year they have noted the upstream migration of 

 millions of elvers three to four inches in length and slightly smaller than 

 the diameter of a pencil. Elvers migrating up the stream are thought to 

 be females while males remain behind in the estuaries. 



Both sexes feed voraciously during their stay in fresh water which 

 may extend anywhere from 5 to 20 years. When adults reach sexual 

 maturity they grow darker, lose their voracious appetites and begin 

 their downstream migrations. Their destination is somewhat southeast 

 of Bermuda in the Sargasso Sea in the warmest waters of the North 

 Atlantic. Here they spawn and die. 



When first hatched the small eels are known as leptocephali, shaped 

 in the manner of a leaf and transparent. These larval eels reach the 

 coast of United States in autumn of their first year, attain their full larval 

 development that winter, and are ready to move up the rivers in the 

 spring as elvers. These elvers then are the young of the adults that mi- 

 grated downstream over a year ago rather than the previous fall. 



The eel has the reputation of being a voracious fish. Females com- 

 monly reach a length of three to four feet and occasional large ones are 

 taken six feet in length. Males are smaller. 



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