292 Thread Herring 



4!/2 inches long. They then move down to the sea, where 

 they spend the remainder of their lives, entering the rivers 

 only to spawn. They spawn for the first time when about 4 

 years old and commonly return to the river of their birth 

 for this purpose. Like the other herrings, the Shad feeds 

 primarily on plankton. 



Economic Importance: An important food species. Con- 

 struction of impassable dams on many of the rivers and 

 streams and pollution of other rivers and streams have 

 eliminated or reduced the runs of this fish in numerous 

 places. When running upstream to spawn the Shad will 

 strike readily on an artificial lure and makes an excellent 

 adversary on light tackle. A spectacular sport fishery for 

 Shad has been developed in Connecticut at the Enfield 

 Dam. 



Thread Herring 

 Opisthonema oglinum (LeSueur) 



Color: Blue above; silvery sides and belly. Faint dark spot 



behind upper margin of gill cover. Dark horizontal streaks 



on upper part of body. Tips of dorsal and caudal fins 



black. 



Distribution: Found from Brazil to North Carolina and 



as a stray as far north as Cape Cod. 



Size: Reaches a maximum length of about one foot. 



General Information: Little is known about this species. 



It is most abundant in the West Indies. 



Economic Importance: None. 



