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Fishery Bulletin 88(3), 1990 



Figure 1 



Location of sampling area off Freeport, Texas. Sta- 

 tion depths and bathymetric contours are indicated 

 in meters. 



86, and 100 m after May 1979. Collections were made 

 during the day through September 1978; thereafter, 

 a day and a night cruise were usually made each month. 

 Usually, two tows of 10 minutes bottom time were 

 made at each depth, except that 8 were made at 16 m, 

 24 were made at 22 m, and only 1 tow was made at 

 most depths prior to October 1978. We emphasize our 

 spatial sampling design was a single, cross-shelf 

 transect from a sampling frame that encompassed 

 much of the northern Gulf. 



All P. octonemus were culled from the catch, mea- 

 sured to the nearest millimeter total length, fixed in 

 10% formalin, and then preserved in 70% ethanol. All 

 individuals collected January-December 1979 were 

 processed to determine the following: total length (TL), 

 fork length (FL), standard length (SL), girth at origin 



of the dorsal fin (G), total weight (TW), gonad weight 

 (GW), and sex and gonad maturity stage. If available, 

 200 fish were randomly selected for similar process- 

 ing in all other months, except standard length and 

 girth were not recorded. Gonad maturity (Table 1) was 

 determined by a modification of the Kesteven classifica- 

 tion (Lagler 1978). Fish in the Early Developing and 

 later stages were considered mature to calculate 

 maturity curves (Bowering 1983), which indicate the 

 length when half were mature (Mr,,,). Gonadosomatic 

 indices (GSI) were calculated for individual fish as: GSI 

 = 100 GW/TW. 



Age in years was determined by length-frequency 

 analysis, e.g., the modal group progression analysis 

 modification (Jearld 1983) of the Petersen Method 

 (Lagler 1956). Knowing from this that essentially all 



