efficiency) to support the total epibenthic production of 0.06 g C/nrVyr 

 (Flint 1979). This finding suggested that organic detritus was of 

 particular importance to the trophic system. 



Much of the organic detrital materials on the shelf are transported 

 by the discharge of rivers and estuaries into the surface waters of the 

 nearshore shelf during spring, promoting a spring bloom of primary 

 production. These materials ultimately sink to the bottom, supplemented 

 by organic materials produced in the surface water layers. The bottom 

 serves as a nutrient reservoir and likely dampens the effects of the 

 surface productivity cycles if bottom turbulence is sufficient to 

 resuspend the material. The ease with which the bottom can be 

 resuspended, enabling the nutrients to be recycled and released, may be 

 greatly influenced by the amount of bioturbation from the infauna and 

 epifaunal species which disturb or otherwise bioturbate the bottom. 



Flint (1979) concluded that although the benthic infauna do not 

 necessarily provide all of the direct food source for the benthic 

 epifauna, they are important in that they supplement the diet of 

 demersal consumers and indirectly provide alternative nutritional 

 sources through their bioturbation activities. Results by Gall away and 

 Reitsema (1980) suggest that benthic infauna may be exceedingly 

 important, not in the amount of food they represent, but in that they 

 serve to accumulate and concentrate certain sterols and fatty acids 

 which are required for sexual maturation by species such as brown and 

 white shrimp. 



A conceptual model for artificial reefs on the Texas- Louisiana 

 shelf (mainly petroleum platforms) has been described by Gallaway et al. 

 (1980). The physical presence of the platforms was presented as the 

 major factor controlling, or accounting for, the three general biotic 

 assemblages which aggregate at these sites — the biofouling, pelagic, and 

 benthic reef fish communities. Of these, the biofouling community was 

 the most complex. The diversity and biomass levels of the biofouling 

 community that develops are controlled by the type of perennial shelled 

 animal that dominates. Barnacles (or other shelled organisms) provide 

 habitat diversity, space, and food for other organisms. Barnacles are 

 preyed upon largely by fish such as sheepshead and triggerfish, species 

 capable of crushing their protective shells. In their grazing, these 

 fish do not always consume all the shellfish, and the remains are 

 available to smaller predators such as blennies. Blennies, in turn, are 

 sometimes taken by the epifaunal grazers as well as by other fish 

 predators, such as amberjack or almaco jack. Even though cycling is 

 undoubtedly high (Gallaway and Margraf 1978), the biofouling community 

 probably obtains most of its food in the form of plankton and 

 particulates flowing through the system. Some species are recruited to 

 the biofouling community from outside the system (e.g. stone crab 

 larvae, adult sheepshead). Losses from the biofouling community include 

 those from reproduction, breaking-off and sloughing, as well as to man. 



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