their larger standing crops of phytoplankton, zoo- 

 plankton, and benthos (Flint and Rabalais 1981) 

 which are capable of supporting the large shrimp 

 fishery yield in these waters. 



Based upon a desire to better understand the 

 characteristics of an important resource of the 

 Texas continental shelf, we used the south Texas 

 environmental study data as well as information 

 from the published literature to develop a model of 

 the trophic relationships supporting the brown 

 shrimp fishery. This analysis provided insight into 

 the general structure of marine ecosystems which 

 support fisheries. It also provided the necessary 

 data to judge whether the generalization of Dickie 

 (1972) and Mills (1975)— that despite geographic 

 differences most coastal ecosystems with produc- 

 tive fisheries have similarly constructed food 

 webs — is well founded or not. 



FISHERY BULLETIN: VOL. 79, NO. 4 



METHODS 



A multidisciplinary research program ( 1975-77) 

 was conducted on the south Texas outer continen- 

 tal shelf (STOCS) at 25 stations (Figure 1). The 

 study included water mass characterization, 

 pelagic primary and secondary production as de- 

 scribed by floral and faunal biomass, and benthic 

 productivity as described by macroinvertebrate 

 infaunal and epifaunal densities as well as demer- 

 sal fish densities and biomass. The study, sum- 

 marized by Flint and Rabalais (1981), provided a 

 data base depicting the general characteristics of a 

 marine subtidal area with important natural re- 

 sources. 



The focus of the results presented in this paper is 

 on data collected from a "Reference Station" (Fig- 

 ure 1) which we consider representative of Statis- 



9 7° 30 



97°00 



96°30 



96°00 



95°30 



Figure L— Map of the south Texas con- 

 tinental shelf with location of sampling 

 sites for 1975-77 environmental study. 

 NOAA shrimp catch Statistical Area 20 

 is superimposed along with the Refer- 

 ence Station representing the source of 

 data used in the text. 



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