Comment 



Some models which can be used for impact analysis only require that 

 the relative number of winter flounder (total, within various age groups, 

 etc.) be known from year to year, not the absolute number. This would 

 eliminate the necessity of making a population estimate and instead an 

 index of relative annual abundance such as CPUE, which is more easily 

 obtained, could be taken. However, the long time series of winter 

 flounder population data needs to be analyzed in further detail to see 

 if a good measure of CPUE can be obtained without sacrificing the accuracy 

 and precision known about each estimate. Preliminary analysis has shown 

 that a satisfactory relationship has yet to be found between the population 

 estimates and CPUE as much variability exists within and between years. 

 The data may not be entirely satisfactory for this purpose as unlike the 

 trawl monitoring program, the sampling for winter flounder from 1975 

 through 1981 was not designed to measure CPUE. It is recommended that 

 further work be undertaken to develop a satisfactory index of yearly 

 relative abundance from the winter flounder population survey data. 



JUVENILE AND ADULT LIFE HISTORY OF THE WINTER FLOUNDER 

 Summary of methods 

 Beginning in 1975, 100 to 200 winter flounder were measured each 

 week of the population survey. Although all fish from a particular tow 

 were measured to avoid selection bias, the tows themselves were not 

 randomly selected. Tows from various stations in the River were chosen 

 for measurement to obtain a complete representative sample. In 1976, 

 the sex of each fish captured was determined insofar as possible by 

 external examination using the method of Smigielski (1975) and a portion 



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