to 



UJ 



175 



150 " 



125 



Q 



3 100 



o 



Q. 



u- 



o 



oo 75 



Z 



o 



5 50 



25 



UNITED STATES OYSTER PRODUCTION 

 (CRASSOSTREA VIRGINICA) 



CHESAPEAKE BAY OYSTER PRODUCTION 



_L 



_L 



_L 



_L 



J_ 



J_ 



_L 



X 



J L 



1880 90 1900 10 20 30 40 50 60 1965 



Figure 1. — Production of oysters (Crassostrea virginica) in Chesapeake Bay and in the United States, 1880 to 1965. 



Modified from Galtsoff (1956) and Engle (1966). 



The oyster fisheries in Maryland and Vir- 

 ginia waters of the Bay are very different 

 (fig Z), Most of Maryland production is from 

 public beds, and the State has carried on a 

 vigorous large-scale program of shell planting 

 and seed transfer since 1961. Virginia produc- 

 tion, on the other hand, is principally from 

 private beds, most of which have depended on 

 the James River as a seed source. 



Total oyster production in Chesapeake Bay 

 over the last two decades (fig 3) shows the 

 same distressing downward trend from 1954 to 

 1964, despite Maryland's oyster shell planting 

 program and Virginia's private planting. Pro- 

 duction has slipped from about 40 million 



pounds to only 20 million during this period. 

 We have good evidence that disease has been 

 responsible for much of the decline since 

 1960, particularly in Virginia waters. 



The disease outbreak responsible for oyster 

 mortalities in Chesapeake Bay actually began 

 several years earlier--probably about 1 955 — 

 in Delaware Bay. The oyster industry there 

 was almost completely destroyed by 1959 and 

 has shown little recovery (fig 4). Production in 

 New Jersey waters of Delaware Bay dropped 

 from a high of 7.5 million pounds of shucked 

 meats in 1953 to a low of only one-third of a 

 million pounds in 1960. Mortalities in Delaware 

 Bay reached 85 percent in certain beds. 



