4 





/ ; c 





r 



83 



Figure 1. — General area in which mark-recapture experiments were conducted. Large numerals (1-4) identify 

 coastal subareas employed in tabulating fishery statistics. Data shown in subarea 2 refer to the Tortugas ex- 

 periment (September- December 1961), those in subarea 4 to the Sanibel experiment (December 1960- June 1961). 



Annually contributing about 10 percent to the 

 total Gulf production of shrimp, landings in the 

 Tortugas fishery reached a peak of 23.6 million 

 pounds in 1960, having risen from almost a record 

 low of 12.9 million pounds the year before. The 



latter value represented a 44-percent drop from 

 the previous high of 23.0 million pounds landed in 

 1958. 2 Since 1956 the fishery has seemingly had 



« Source: Gulf coast shrimp data, published monthly by the Branch of 

 Fishery Statistics, Bureau of Commercial Fisheries, U.S. Fish and Wildlife 

 Service. 



DYNAMICS OF A PENAEID SHRIMP POPULATION 



315 



