S. The best overall estimate of survival is then found by converting 

 the simple mean of the individual estimates of Z back to S. The mean 

 survival of Niantic River winter flounder using this technique was 

 0.4823 (Table 25). However, the differences among the individual estimates 

 again indicates systematic differences in mortality which may have been 

 due to sampling errors or by age-specific differences in mortality. 



Several methods of calculating time-specific mortality were investi- 

 gated. These included the methods of Heincke, and Robson and Chapman 

 (Ricker 1975) which gave survival estimates of 0.5142 and 0.5011, respec- 

 tively (Table 24). A plot of log frequency against age (catch curve 

 method) gave an estimate of 0.4982 (Table 26). These different methods 

 gave relatively similar estimates of survival which were considerably 

 higher than that reported previously by use of the simple age ratio 

 method. 

 Disc tagging 



To date 518 recaptures of disc-tagged winter flounder have been 

 made (14.3% of the number tagged). Many of these fish were recaptured 

 during the winter flounder surveys and the trawl monitoring program and 

 subsequently were released a second time. Most of the returns from the 

 public were divided about equally between the sport and commercial 

 fisheries. Returns from 1980 and 1981 tagged fish indicated that adults 

 were generally found during summer in Niantic Bay and at locations a few 

 miles to the east in New London County waters; some individuals moved 

 further east along the coast of Rhode Island and Massachusetts. Very 

 few tagged winter flounder moved westerly within Long Island Sound and 

 very few have been impinged at Millstone. Analysis of returns in 1982 

 and subsequent years should reveal whether tagged winter flounder return 



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