19. Growth of young in the lower river was significantly greater than at stations upriver after mid-June. 

 Weekly mean lengths in 1983 were about 6 to 8 mm larger than in 1984 or 1985. Monthly survival 

 estimates of young ranged from 0.552 to 0.569. 



20. Peak abundance of age 1 juvenile winter flounder taken in the Niantic River during the adult surveys 

 occurred in 1981, with second and third highest CPUE in following years. An U-yr low was found 

 in 1986. However, in recent years juveniles have been found in more areas throughout the river and 

 in Niantic Bay during the time of the surveys. This variation in distribution makes the estimation of 

 juvenile abundance less certain than that of adults. 



21. About two-thirds of the total number of winter flounder impinged on the traveling screens of MNPS 

 were taken in winter. Before 1 984, annual estimates usually ranged from 4 to 1 thousand with winter 

 storms accounting for large proportions of most annual totals. 



22. Sex ratios and reproductive condition of impinged fish differed from fish taken in the river. The 

 predominance of males and of gravid females in the collections indicated that at times impingement 

 was related to behavior of winter flounder. 



23. A fish return sluiceway was installed at MNPS Unit 1 in December of 1983 and studies showed that 

 survival of returned winter flounder would be considerable (ca. 80-90%). This greatly reduces the 

 impact of impingement on the winter flounder. 



24. Entrainment sampling has been conducted since 1976. A majority (>60%) of the winter flounder 

 larvae entrained were 5 mm and larger. The greatest entrainment densities occurred from mid-April 

 through May. Based on the median annual entrainment density, three years were low (1977-79), four 

 years were high (1976, 1980-83), and the remaining years were intermediate. Annual entrainment was 

 related to total egg production in the Niantic River and the length of time a larva was susceptible to 

 entrainment was related to water temperature. 



25. The effects of entrainment on larval winter flounder were examined in the laboratory and field, larvae 

 5 mm and larger were able to survive a AT of 13° C for up to 9 h. The estimated critical thermal 



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