shoreward banks were characterized by the presence of V and VII or VI 

 and VII. The South Texas banks having low values (3) were characterized 

 by the presence of Zone VII only. 



Abundant and common fishes characteristic for areas near the tops 

 of banks on the outer shelf include barracuda, creole wrasse (Cleoticus 

 Parrai) ; Creole fish ( Paranthias furcifer) ; several species of jacks 

 (particularly the almaco jack, Seriola rivoliana ); a number of species 

 of angelfishes, butterfly fishes, damselfishes and parrotfishes 

 (Scaridae); and other reef forms. In deeper zones, several species of 

 the snapper-grouper assemblage predominate, including forms such as red 

 snapper, groupers of the genera Mvcteroperca and Epinephelus , vermilion 

 snapper ( RhombOPliteg aurorubenj?) and cottonwick ( Haemulon melanurum) . 



The sessile epifauna on platforms of the outer shelf that I have 

 observed has been relatively little developed. Macroalgae and stalked 

 barnacles were present at the surface of some of the structures while 

 pel ecy pods and hydroids were found deeper. As at some of the offshore 

 banks, spiny lobster ( Panullrus sp.) are included in the fauna. The 

 most striking feature of these platforms, however, is the dominance of 

 the fish community by tropical reef forms. The barracuda is an abundant 

 large predator and almaco jack and blue runner appear to be the dominant 

 schooling pelagic species. The Creole fish may be the dominant 

 platform-associated fish. Spadefish and sheepshead are typically 

 absent; gray triggerfish are abundant. Vertical members of these 

 platforms are surrounded by swarms of tropical species. The 

 damselfishes, angelfishes and tangs are abundant, but, on platforms I 

 have seen, are overshadowed by the abundance of certain wrasses, 

 particularly creole wrasse and Spanish hogfish ( Bodianus rufus) . Other 

 tropical species which I have observed here but not at any inshore 

 platforms included the rock beauty (Holacanthus tricolor) , reds potted 

 hawkf ish ( Amblvcirrhitus .pJLnflal and red hogfish (Decodon puellaris) . 

 The platform fish assemblages are similar to those seen on the natural 

 banks (Bright and Pequegnat 1974; Bright and Rezak 1978). 



CONCEPTUAL MODEL AND SYSTEM PROCESSES 



The two inner-shelf faunal assemblages defined above, while 

 generally bathymetrically distinctive in terms of species composition, 

 are similar in terms of their structure, function and trophic dynamics. 

 Both are basically two-layered systems (pelagic and benthic) with the 

 major biological resource being represented, in each case, by penaeid 

 shrimps, a component of the soft-bottom benthic epifaunal community. 

 The epifauna of the benthic community (the shrimps in combination with 

 demersal fishes) likely dominates the system in terms of overall 

 biomass. Characteristic species from both soft-bottom assemblages are 

 characterized by (1) small size (most less than 20 cm long), (2) short 

 life spans ( 1 to 3 yr) , (3) high (90$ or more) annual mortality rates, 

 and (4) high fecundity and extended spawning seasons (Chittenden and 



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