The temporal occurrence of each developmental stage in the river and bay from 1983 through 1985 

 was compared using the dates of peak estimated abundance (Table 23). These dates were estimated from 

 the inflection point (Equation 8) of the same Gompertz function that was used to estimate the a parameter 

 above. Since 1983, the dates of peak larval abundance have been very similar for Stage 1 in the river and 

 Stage 2 in the river and bay. The lag in peak abundance of Stage 2 in the bay compared to the river 

 ranged from 17 to 23 d. This difference between the river and bay may be related to flushing rate because 

 the average retention time of a passive particle in the Niantic River was reported as 25 d by Moore and 

 Marshall (1967) and 27 d by Kollmeyer (1972). Within each year, the dates of peak abundance for Stage 

 3 were similar in the river and bay. The greatest difference in dates among years was for Stage 4 larvae, 

 which in 1983 peaked earlier than either 1984 or 1985. The similarity in the estimated dates of peak 

 abundance, particularly Stage 1 larvae in the river, indicated that peak spawning occurred approximately 

 at the same time during the 3-yr period. Based on water temperatures of 2 to 3 °C during the latter 

 portion of February and egg incubation times reported by Buckley (1982), peak spawning probably 

 occurred in mid-February. The lack of Stage 1 larvae in the bay showed that spawning took place almost 

 exclusively in the river and the lag in Stage 2 abundance represented the gradual flushing of larvae from 

 the river to the bay. The similarity in the date of peak abundance for Stage 3 larvae between the the river 

 and the bay in each year indicated that by this stage of development the dispersion of larvae from the 

 river to the bay was completed. 



Table 23. Estimated date of peak abundance oflarval winter flounder in the Niantic 



River and Bay from 1983 through 1986. 



72 



