Because the catch data were historically converted to a CPUE based 

 on a 15min tow, a qualitative evaluation of this procedure was made 

 prior to any critical analyses of the data. The frequencies of the 

 catch per haul were fairly similar regardless of whether a 'tow' was 

 15min or 0.69km. Winter flounder and scup (Fig. 2 and 3) were repre- 

 sentative of the catch distributions of the trawl-caught species. 

 However, the distribution of the tow durations (Fig. 4) were distinctly 

 different after the change to a distance basis. The effect of dividing 

 the catches by the durations would be to increase the variance of the 

 time-based CPUE collected after October 1977 so that AOV tests for 

 comparisons before and after this data would be inappropriate. Thus, 

 the data used in the AOV of catch statistics were limited to those 

 collected since October 1977 and were expressed as 'catch per 0.69km'. 



The trawl catches varied with date, station and species. Two 

 extreme patterns of catch are exhibited by the winter flounder, a year- 

 round resident of the greater Millstone Bight, and the scup, a summer 

 migrant to the area. While a seasonal pattern is more obvious from the 

 scup catch, both of these species exhibit fairly repeatable annual 

 patterns at some if not all stations (Fig. 5-6). 



Specific patterns of distribution over time and space were typical 

 of the selected trawl species, and resulted in some species being absent 

 from certain seasons and stations. Threshold criteria were used to 

 select the data from those times and places where a species was caught. 

 If a species' catch was uniformly distributed over all months and stations, 

 8% of the catch would occur in each of 12 months and 16% would be found 

 in each of 6 stations. A species was considered 'absent' if it did not 

 contribute at least half of these percentages (4% or 8%) to a given 



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