Table 35. The a parameter as an index of abundance and the date of 



inflection as an estimate of the date of peak abundance from the 

 Gompertz function for larval winter flounder entrained from 1976 

 through 1985. 



The estimated date of peak density at EN varied from April 13 in 1976 to May 18 in 1977. For the 

 period of 1981-85, a similar pattern in the timing of peak abundance was also evident in the abundance 

 curves for Niantic Bay with stations NB and EN combined (Fig. 13). The estimated date of peak 

 abundance was determined from the inflection point of Gompertz function. This inflection was caused 

 by the decline in larval abundance and for EN data the decline was partly caused by the decrease of larvae 

 through recruitment to the juvenile stage. Because water temperature could affect the rate of development 

 to juveniles, temperatures during the entrainment season were compared to the timing of peak abundance 

 (Fig. 33). Temperature was expressed as the yearly deviation during March through May from the average 

 temperature for the 10-yr period. Time of peak abundance was the number of days after February 15 

 that the peak occurred each year. It appeared that as water temperature increased, the date of peak 

 abundance was earlier. This could be related to faster developmental rate to the juvenile stage or changes 

 in annual time of spawning (Fig. 5) due to water temperature. Although other factors could affect these 

 parameters, it was apparent that numbers entrained were probably related to total egg production in the 

 Niantic River and the length of time a larva was susceptible to entrainment, which was in turn related to 



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