114 BULLETIN OF THE BUREAU OF FISHERIES 



It has a deeply-forked tail and large and very easily loosened scales. Unlike the 

 sea herring, however, the shad has no vomerine teeth — adults, indeed, have no 

 teeth at all, although young shad have small ones in the jaws which may persist 

 imtil the fish is a foot or more long. It is easily recognized, being the deepest 

 bodied of our herrings, a third as deep as long, and further marked among its relatives 

 by the fact that the upper jaw is deeply notched at the tip with the end of the lower 

 jaw fitting into the upper when the mouth is closed. The mouth, too, opens back 

 farther than in the alewives, and the edge of the lower jaw is straight, not concave, 

 as in the latter. The under jaw does not project noticeably beyond the upper, as in 

 the alewives and especially in the hickory shad. Furthermore, the lining of the 

 shad's belly is white — neither gray as in the herring and alewife nor black as in the 

 blueback. 



Size. — The shad is the largest of herrings that regularlj' visit our Gulf, growing 

 to a length of 2^ feet. Adult males rim in weight from IJ^ to 6 pounds; females 

 from 3}^ to 8 pounds. Shad are occasionally reported up to 12 pounds, and the 

 older writers mention them as heavy as 14 pounds, but none so large has been 

 credibly reported in the Gulf of late 5'ears. 



Color. — Dark bluish or greenish above, white and silvery on sides and belly, 



Fig. 47 — Larva of the shad (Alosa sapidissima), 17 days old 



with a dusky spot close behind the rear edge of the gill cover, and frequently with 

 several indistinct dusky spots in one or two longitudinal rows behind it. 



General range. — -Atlantic coast of North America from the Gulf of St. Lawrence 

 to Florida, and represented by a close ally or variety in the Gulf of Mexico. It 

 also has been successfully introduced on the Pacific coast of the United States. 

 It runs up rivers into fresh water to spawn. 



Occurrence in the Gulf of Maine. — When the first settlers arrived in New England, 

 they found seemingly inexhaustible multitudes of shad annually running up all the 

 larger rivers and many of the smaller streams from Nova Scotia to Florida, with the 

 tributaries of the Gulf of Maine hardlj^ less productive than the Hudson or Delaware; 

 but as one stream after another was rendered impassable, or at least very difficult for 

 the fish to ascend, by the construction of dams near the mouths, the local stock of 

 shad has diminished until now the Gulf of Maine stock is but a shadow of its former 

 abimdance, a fact more than one writer has taken a melancholy pleasure in lament- 

 ing. Since it is the present status of the shad with which we are now concerned, 

 the following table of the shrinking catch in the Merrimac will be a sufficient illus- 

 tration of this depletion." 



" From Stevensen (1899). 



