April. The sex ratio of Impinged winter flounder (1.86:1 in favor of 

 males) was the ojiposite of that seen In the Nlantlc Klver. Males may 

 have had a lesser ability then females to escape Intake currents at 

 MNPS. 



Winter flounder larvae were entrained at MNPS from late February 

 through late June with highest densities in April and May. The 1983 

 entrainment estimate was the second highest since 1976, but due to 

 overlap in confidence intervals, no significant differences were found 

 among years. Data from an entrainment survival study indicated that a 

 large portion of older larvae could survive entrainment; 15% of those 

 entrained during 1983 were in these stages of development. 



Fluctuations in the catch of winter flounder in several monitoring 

 programs were analyzed using time-based harmonic regression models. The 

 entrainment and impingement programs provided data which led to 

 reasonably well-described models; forecasted catches for 1982-83 were 

 similar to those actually made. In contrast, models developed from the 

 trawl monitoring program data were inadequate. This may have been due 

 to the large variability in the trawl catches or because the winter 

 flounder has fluctuations in abundance greater than the 6-year period 

 examined . 



HEAVY METALS 



Concentrations of heavy metals (e.g., copper, zinc, iron, chromium 

 and lead) in seawater and in shellfish tissue samples collected in the 

 Millstone Point area were monitored five times (February, May, July, 

 September and December) during 1983. Seawater and shellfish tissues 

 were examined to detect any possible increases in metal concentrations 

 resulting from passage of water through the cooling water system of the 

 Millstone Nuclear Power Station. 



The levels of dissolved metals in seawater samples taken during 

 1983 were similar to 1982. Quarry and plume waters were slightly 

 enriched with dissolved Cu and Zn, although higher levels of Zn were not 

 consistently found. Cooling water is evidently not an enriched source 

 of the other metals. 



