Atlantic coast. The total catch in that year, 

 18,068,102 lb., was reported to be a decline 

 in yield. After 1880, however, improved 

 methods of capture and more vigorous prose- 

 cution of the fisheries resulted in a consid- 

 erable increase in production. In 1888 the yield 

 was 35,636,618 lb. (97-percent increase over 



Table 54. --Shad catch for certain years, Atlantic coast of 

 the United States, 1880-1960l 



[In thousands of pounds] 



1880). In 1896 the fishery reached its peak 

 production of 50,498,860 lb. Productivity was 

 still high in 1908 when more than 25 million 

 pounds were taken. After 1908 production de- 

 clined, and by 1932 was less than 10 million 

 pounds. Since 1932 the catch has remained 

 low--between 14,699,000 lb. in 1945 and 

 7,799,000 lb. in 1953. The 1960 yield showed 

 an increase of 5 percent from 1953, but was 

 only 16 percent of that in 1896. 



In the first half of this report, we gave an 

 account of the comparative abundance of shad 

 in each river or area, and conditions in each 

 locality were described. In the final portion, 

 the factors responsible for the decline in 

 production are discussed, as well as the 

 methods that are or might be used to re- 

 habilitate and manage the fishery. 



YEARS 



^ Data 1880-1959, statistical publications of the U. S. 

 Bureau of Fisheries, and U. S. Fish and Wildlife Service. 



Figure 28. — Shad catch, Atlantic coast of the United States, 

 for certain years, 1880-1960. 



FACTORS AFFECTING DECLINE IN ABUNDANCE 



Stevenson (1899) stated that the fishery had 

 undergone great changes during the 19th cen- 

 tury and that there were few fishes other than 

 the shad whose geographical range and local 

 abundance were more easily affected by nnan. 

 In some areas a decline in abundance had be- 

 gun previous to 1880, though this change was 

 not well documented. Construction ofdannshad 

 excluded shad fronn many of the historical 

 spawning grounds. Sawdust, chemicals, as- 

 sorted refuse, and agricultural operations had 

 greatly impaired the utility of available spawn- 

 ing grounds. In his comparison of the yield 

 of the entire coast in 1880 and 1896, Stevenson 

 pointed out, however, that the catch had in- 

 creased more than 57 percent. He further 

 stated that increased yield followed an in- 

 crease in the quantity of gear used. In 1896, 

 45 percent of the catch was from areas which 

 half a century before had yielded no shad. 

 Thus, it appears that one of the principal 



changes in the fisheries prior to Stevenson's 

 study was location of exploitation rather than 

 the change of total yield. 



The commercial production of shad on the 

 Atlantic coast has decreased about 84 percent 

 since 1896. Many factors have been blamed 

 for the decline. Among these were: physical 

 changes of the environment which rendered 

 it unsuitable for spawning or which influenced 

 survival of eggs and larvae; construction of 

 dams which barred fish from fresh-water 

 spawning areas; pollution which rendered 

 rivers unsuitable for reproduction and sur- 

 vival of this species; overfishing which did 

 not allow enough fish to spawn and replace 

 those taken by the fishery; and natural cycles 

 of abundance. 



One of the purposes of the shad investiga- 

 tion begun by the Fish and Wildlife Service 

 in 1950 was to determine causes for decline 

 in abundance of the species and to suggest 



90 



