20 



16- 



Q 12- 



25 50 75 100 125 150 



ESTIMATED ENTRAINMENT OF LARVAE IN MILLIONS 



175 



Fig. 39. Relationship between the annual age 3 recruitment index and annual estimated entrainment of winter 

 flounder larvae at MNPS for the 1976 through 1984 year-classes. 



ments, especially those flushed from the Niantic 

 River, are needed. Also, little is known about 

 the fate of larvae in Niantic Bay or the number 

 removed from the area by tidal currents; the mag- 

 nitude of larval metamorphosis in the bay; and 

 whether or not post-larval young reside in the 

 bay or are successful in moving into suitable nurs- 

 ery areas, such as the Niantic River. Larval aging 

 is necessary to accurately determine rates of mor- 

 tality and grovrth. The source of entrained larvae 

 is not known with certainty. Although evidence 

 from the larval sampling program suggests that 

 the Niantic River is the likely source of most 

 entrained larvae, drift of larvae from other areas 

 of Lx)ng Island Sound into Niantic B?.y carmot 

 yet be ruled out. Sampling programs designed 

 specifically to address the above concerns will be 

 initiated in 1988 (NUSCO 1988a, 1988b). 



Conclusions 



Abundance of adult winter flounder in the 

 study area around Millstone remained low in 

 1987, with numbers similar to those of 1984-86. 

 The changes in abundance of local winter flounder 

 during the past 12 years were similar to those 

 taking place in other areas of Southern New Eng- 

 land, as shown by significant correlations among 

 the various abundance indices examined. This 

 suggested that winter flounder populations were 

 most likely affected by factors operating region- 

 wide, which influenced reproduction and subse- 

 quent recruitment and, perhaps, from similar fish- 

 ing pressures on the adult stocks. Historical 

 records showed that the species has repeatedly 

 fluctuated in numbers with periods of low and 

 high abundance. 



Winter Flounder Studies 



213 



