The effects of produced water on the condition of the Mediterranean 

 barnacle were reported by Boland (1980). Barnacles taken from locations 

 as close as 1 m to the surface at the outfall were not significantly 

 different in condition from those taken at control stations. He did 

 find, however, that barnacles taken immediately below the sewage outfall 

 were characterized by significantly better condition than barnacles 

 taken in control areas. He also found that Mediterranean barnacles from 

 the BGOF were characterized by significantly better condition than the 

 same species collected from a structure offshore from West Cameron, 

 Louisiana. 



Barnacles did not contain measurable amounts of petroleum alkanes 

 but the fouling mat in the immediate vicinity of the outfall was 

 observed to have been oiled by direct exposure to produced water. The 

 cryptic blennies, which were relatively insensitive to produced water 

 (96-h LC50 = 27$) and which were apparently attracted to the area of 

 outfall (Gallaway and Martin 1980), also showed evidence of marked 

 petroleum contamination. The mean alkane concentration in this fish in 

 1978-79 was 6.79 ppm» considerably higher than levels found in any other 

 fish. No evidence of any significant trace metal contamination of the 

 biofouling community attributable to production activities was found 

 during the BGOF investigations. 



The effects of produced water on several species of 

 platform-associated fish were also investigated in the BGOF program. 

 Target species included the crested blenny and sheepshead, which rely 

 upon the biofouling community for food; the spadefish, which takes most 

 of its food in the form of plankton and particulates from the water 

 column, and the red snapper, which feeds on epifaunal organisms from the 

 soft bottoms away from the platforms. 



Blennies exhibited an apparent attraction to the area of produced 

 water discharge. Highest densities were observed on production 

 platforms, and on these platforms, significantly higher densities were 

 observed near the outfall than elsewhere. Based upon in-situ 

 investigations, the effluent had no significant effects on 

 recolonization rates of areas harvested of blennies, nor were there any 

 significant effects on condition of blennies. 



The apparent attraction to the outfall area may have been 

 attributable to the combination of a greater level of habitat 

 availability due to higher densities of both live and dead barnacles in 

 these areas (Howard et al. 1980) and the apparent lack of sensitivity 

 of the crested blenny to produced water (96-h LC50 was 269,000 ppm or 

 about 27% produced water in seawater). 



The crested blenny differed little from other BGOF fishes in terms 

 of its bacterial flora. Species of Vibrio were the most common taxa 

 during each season; hemolytic Vibrio were not isolated from fall 



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