The observed ratios were similar to those reported by Saila (1962a, b) 

 and Howe and Coates (1975). Observations of female winter flounder 

 spawning in the Niantlc River during recent years Indicated that sexual 

 maturity was achieved at about 25 cm, when the fish were from 3 to 5 

 years old (NUSCo 1983). This was confirmed by a probit analysis of the 

 1983 data, which produced a 50% sexual maturation estimate of 25.1 cm 

 with a 95% confidence Interval of 24.2 to 25.9 cm. Based on oocyte 

 development time, the minimum age of reproduction for winter flounder 

 was reported as 3 years (Dunn and Tyler 1969; Dunn 1970). However, 

 maturity in many flatfishes is probably governed by size as well as age 

 (Roff 1982). The 25-cm median size of maturity found for the Niantlc 

 River winter flounder was the same as that reported by Kennedy and 

 Steele (1971) for a Canadian population with an average age of maturity 

 of 7 years. Thus, the Niantlc River stock probably has reached lower 

 limits for age and size of first reproduction. Accelerated maturation, 

 which may be found in reduced or stressed populations (Nikolsky 1963; 

 Roff 1982) , probably cannot occur any further in the Niantlc River 

 stock. 



In previous years some of the information used to estimate 

 reproduction was gathered by individuals in the field who noted spawning 

 condition of each female; fish were recorded as ripe, spent, or 

 non-classified. Only the proportion of females in the first two 

 categories was used to estimate the abundance of spawners and egg 

 production. This procedure probably caused an underestimation in the 

 number of spawners because of Individual bias and errors in observation 

 and classification; over the years varying percentages of females of 

 different size-classes were classified as non-spawning regardless of 

 their length or age. For this report it was assumed that most, if not 

 all, adult females found in the Niantlc River during the spawning period 

 reproduced there. All females larger than 25 cm were used in estimating 

 the number of spawners and total egg production found in Table 5. This 

 change as well as increases in estimated numbers of female spawners 

 resulted in generally larger estimates of eggs produced from 1977 

 through 1982 than reported in NUSCo (1982). The largest yearly increase 

 in number of spawning females and in egg production occurred from 1980 



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