EARLY LIFE HISTORY OF THE WINTER FLOUNDER 

 Summary of_ offshore and entrainment sampling programs for winter flounder 

 larvae 



The winter flounder has been a significant component of the 

 ichthyoplankton at Millstone since studies began in 1973. A detailed 

 review of the ichthyoplankton sampling program, including entrainment 

 and offshore sampling, may be found elsewhere in this report. Only 

 those studies which have been undertaken in whole or in part to provide 

 additional information on the winter flounder are discussed below. 

 Detailed presentations of data and analyses for any particular year may 

 be found in the appropriate Annual Report. 



The extensive ichthyoplankton monitoring program begun in 1973 had 

 as one of its objectives the field verification of a winter flounder 

 larval dispersal model (Sissenwine et al. 1973) including estimating 

 concentrations at the model boundaries and within the model grid. Ten 

 stations (numbers 1-10, Fig. 8) were sampled with a 60-cm bongo sampler 

 (0.333- and 0.505-mm mesh) beginning in May 1973. A variety of tow 

 types (oblique, surface, and bottom) were made both day and night, with 

 day oblique tows predominating. Because of the May startup, few samples 

 contained winter flounder larvae. 



Entrainment studies establishing the seasonality, density, and 

 mortality of entrained larval winter flounder and other species were 

 intensified in March 1973. Weekly samples in triplicate were taken 

 during both day and night at three different depths at the Intake, and 

 at the Discharge, and at the Quarry Cut. The same sampling regime was 

 followed through June 197 5. 



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