NOTE DeLancey et al.: Seasonal sampling of Penaeus postlarvae 



635 



ships. 2 Numbers of shrimp landed each year were 

 estimated by multiplying landed weight by average 

 grade (average number of shrimp per kg). 



Results 



A total of 102,109 Penaeus postlarvae were collected 

 from 7 January 1975 to 3 August 1992 at Breach 

 Inlet. Of the total catch, 68.3% were identified as 

 brown shrimp, P. aztecus, 23.3% as white shrimp, P. 

 setiferus, and 0.8% as pink shrimp, P. duorarum. The 

 remaining 7.6% were identifed as Penaeus spp. The 

 majority of the latter category were tentatively iden- 

 tified as P. aztecus, and were collected primarily from 

 late May through July. Because P. duorarum 

 postlarvae were collected in relatively low numbers 

 and some uncertainty exists with identification, the 

 analysis includes only Paztecus and P. setiferus. 



The majority off! aztecus postlarvae were collected 

 between February and April, when water temperature 

 was between 10 and 20°C (the catch peaked between 

 12° and 16°C ). Penaeus setiferus was collected only when 

 temperatures exceeded 20°C; most were taken at tem- 

 peratures between 25 and 30°C (peak abundance oc- 

 curred in June; Fig. 2). Samples off! aztecus averaged 

 several hundred individuals in each year during times 

 of peak ingress. However, catches of f! setiferus were 



2 Low, R. A. 1992. Survey of the South Carolina Shrimp baiting fish- 

 ery, 1991. South Carolina Marine Res. Cent. Data Rep. 9, 29 p. 



much more variable, averaging zero in some years and 



several hundred in years of high abundance (Table 2). 



Consecutive sampling conducted day and night on 



both ebb and flood tides revealed that both species 



