were taken by extensive overfishing in the late 

 1950's and early 1960's, with a resultant decrease 

 in spawning stock size and age structure. The 

 average catch from 1955 to 1963 was 596,000 

 metric tons, well above the MSY level. The fishery 

 also took greater numbers of fish of smaller size 

 than was compatible with management to insure 

 adequate numbers of spawners. Thus overfishing, 

 which reduced stock size, was compounded by a 

 series of poor environmental years, further re- 

 ducing the spawning stock to a level below that 

 necessary to provide large surplus yields from the 

 higher survival years of 1966 and 1969. Had 

 optimum spawning stock size been maintained, 

 the fishery should have been able to increase its 

 yield during the 1967-71 fishing seasons by an 

 average of 231,000 metric tons/yr. 



The value of a predictive model lies in its 

 usefulness for developing strategies to take 

 advantage of exceptional year classes or to avoid 

 overexploitation of poor year classes. Catches 

 based on the number of recruits calculated from 

 the survival index model are similar to MSY and 

 to those averaged by the fishery (Table 7). 

 However, the absolute mean error from the al- 

 lowable surplus is approximately 134,000 metric 

 tons/yr for the actual fishery landings (1961-71) 

 and 48,000 metric tons/yr if harvest had been 

 limited to the predicted surplus. Some overfishing 

 would have occurred because of errors in pre- 

 diction, but it would have been significantly less 

 than that imposed by the fishery during earlier 

 years. Fishing at a level necessary to harvest the 

 predicted surplus would have provided reasonably 

 stable catches, maintained several age-classes in 

 the fishery, maintained adequate spawning stock, 

 and prevented excessive exploitation of the stocks, 

 all desirable factors in the management of fishery 

 resources. 



ACKNOWLEDGMENTS 



The authors acknowledge a debt to the late 

 Robert L. Dryfoos who was instrumental in the 

 initiation of this work. We also express our ap- 

 preciation to David R. Colby for assistance in 

 computer analyses, to Herbert R. Gordy for the 

 illustrations, and to Valerie N. Ward for assis- 

 tance with the manuscript. 



FISHERY BULLETIN: VOL. 75, NO. 1 



LITERATURE CITED 



BAKUN, a. 



1973. Coastal upwelling indices west coast of North Ameri- 

 ca, 1946-71. U.S. Dep. Commer., NOAA Tech. Rep. NMFS 

 SSRF-671, 103 p. 

 BEVERTON, R. J. H.. AND S. J. HOLT. 



1957. On the dynamics of exploited fish populations. Fish. 

 Invest. Minist. Agric, Fish. Food (G.B.), Ser. II, 19, 533 p. 

 BUMPUS, D. F. 



1973. A description of the circulation on the Continental 

 Shelf of the east coast of the United States. Prog. 

 Oceanogr. 6:111-157. 



CARRUTHERS, J. N. 



1938. Fluctuations in the herrings of the East Anglian 

 autumn fishery, the yield of the Ostend spent herring 

 fishery, and the haddock of the North Sea — in the light of 

 relevant wind conditions. Rapp. P.-V. Reun. Cons. Perm. 

 Int. Explor. Mer 107(3): 10-15. 



Clark, c. W. 



1974. Possible effects of schooling on the dynamics of 

 exploited fish populations. J. Cons. 36:7-14. 



Clark, F. n., and J. C. Marr. 



1955. Population dynamics of the Pacific sardine. Calif. 



Coop. Oceanic Fish. Invest. Prog. Rep. July 1953-March 



1955, p. 11-48. 

 CUSHING, D. H. 



1969. The fluctuation of year-classes and the regulation of 



fisheries. FiskeriDir. Skr. Ser. HavUnders. 15:368-379. 

 1971. The dependence of recruitment on parent stock in 



different groups of fishes. J. Cons. 33:340-362. 



1974. The natural regulation of fish populations. In F. R. 

 Harden Jones (editor), Sea fisheries research, p. 399-412. 

 John Wiley and Sons, N.Y. 



harrison, w., j. j. norcross, n. a. pore, and e. m. 

 Stanley. 



1967. Circulation of shelf waters off Chesapeake Bight. 

 Surface and bottom drift of Continental Shelf waters 

 between Cape Henlopen, Delaware, and Cape Hatteras, 

 North Carolina June 1963-December 1964. U.S. Dep. 

 Commer., ESSA Prof. Pap. 3, 82 p. 



henry, k. a. 



1971. Atlantic menhaden (Brevoortia tyrannus) resource 

 and fishery — analysis of decline. U.S. Dep. Commer., 

 NOAA Tech. Rep. NMFS SSRF-642, 32 p. 

 HIGHAM, J. H., AND W. R. NICHOLSON. 



1964. Sexual maturation and spawning of Atlantic 

 menhaden. U.S. Fish. Wildl. Serv., Fish. Bull. 63:255-271. 



June, F. C, and J. L. Chamberlin. 



1959. The role of the estuary in the life history and biology of 

 Atlantic menhaden. Proc. Gulf Caribb. Fish. Inst., 11th 

 Annu. Sess., p. 41-45. 

 KENDALL, A. W., JR., AND J. W. REINTJES. 



1975. Geographic and hydrographic distribution of Atlantic 

 menhaden eggs and larvae along the middle Atlantic 

 coast from RV Dolphin cruises, 1965-66. Fish. Bull., U.S. 

 73:317-335. 



LEWIS, R. M. 



1965. The effect of minimum temperature on the survival of 

 larval Atlantic menhaden, Brevoortia tyrannus. Trans. 

 Am. Fish. Soc. 94:409-412. 



40 



