GULF OF MEXICO COMMERCIAL SHRIMP POPULATIONS- 

 TRENDS AND CHARACTERISTICS, 1956-59 



Joseph H. Kutkuhn, Fishery Research Biologist 

 Bureau of Commercial Fisheries 



Shrimp populations inhabiting shallow coastal 

 waters of the Chilf of Mexico support intensive 

 and valuable fisheries. Fluctuating about a level 

 of 200 million pounds and trending very slightly 

 upward, annual yields over the past decade 

 (1950-59) have risen steadily in value and gen- 

 erally resulted in increased gross receipts for Gulf 

 fishermen and processors. If ex-vessel sales of 

 landings indicate the relative worth of fish or 

 shellfish supplies, then Gulf of Mexico shrimp 

 stocks now rank, collectiveh", as the most valuable 

 of North American commercial fishery resources. 



The close of the decade saw, however, an ad- 

 verse departure from the value trend established 

 during the preceding 9 years. In 1959, a 22- 

 percent drop in value despite a moderate increase 

 in yield created economic stress throughout much 

 of the hidustry. Sharply rising imports are gen- 

 erally credited with having fostered this plight. 

 The situation brightened somewhat in 1960 when 

 the yield rose still higher and its value jumped 

 15 percent. 



Notwithstanding the effects of expanding im- 

 ports on the utilization of domestic supphes, 

 development of management programs for shrimp 

 stocks in United States coastal waters persists as 

 a major objective. Such programs would so reg- 

 ulate fishing that maximum yields consistent with 

 population stability are realized on a continuing 

 basis.' Preliminary studies which establish how 

 populations react to varying degrees of exploita- 

 tion and, at the same time, to a variable environ- 

 ment, necessarily constitute the framework sup- 

 porting any management program. These studies 

 and, subsequently, the methods used to prescribe 



I ' Changing economy and consumer habits represent important but uncon- 

 trollable variables which may preclude attainment o( "maximum sustained 

 yields." 



Approved (or publication Jan. 24, 1962. 



optimum fishing rates and predict yields, require 

 detailed statistics of past and current fishmg 

 operations. 



Acknowledging this need, the Bureau of Com- 

 mercial Fisheries initiated in 1956 a continuing 

 survey of commercial shrimping activities in the 

 Gulf of Me.xico. On the one hand, this survey 

 provides the fishing industrj- with up-to-the- 

 minute information on trends in shrunp produc- 

 tion and marketing of shrimp products; on the 

 other hand, it furnishes data needed to assess the 

 shrimp resource itself and, ultimately, to formu- 

 late a resource management program. The follow- 

 ing report describes the present survey, reviews 

 trends in annual shrimp yields, attempts an 

 appraisal of commercial shrimp populations em- 

 plojHng commercial statistics, and suggests where 

 improvements would enhance the survey's use- 

 fulness. 



THE GULF OF MEXICO SHRIMP FISHERY 



SPECIES EXPLOITED 



A half dozen or so members of the family 

 Penaeidae (Crustacea: Decapoda) support the 

 extensive Gulf of Mexico shrimp fishery. Only 

 three, however, contribute significantly to the 

 overall yield. The top-ranked species include the 

 brown shrimp, Penaeus azticus Ives; pink shrimp, 

 P. duorarum Burkenroad; and white shrimp, P. 

 setiferm (Linnaeus). Lesser forms in descending 

 order of importance are the seabob, Xiphopeneus 

 krfyeri (Heller); P. bra.siliensis Latreille; P. 

 lichmifti Burkenroad; and Trachypeneus spp. Of 

 these less important shrimps, only the seabob 

 enjoys specific commercial status although it has 

 never contributed more tlian two percent to the 

 total shrimp production in any one year. The 

 remaining species are frequently taken in small 



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