significant intermixing occurring throughout much of the year. The technique could not be used to 

 separate immature specimens. 



14. Several special studies and analyses were conducted to identify possible sampling biases in the larval 

 winter flounder data base. The results of these studies included reduced larval net extrusion with 

 202-nm mesh nets compared to 333- and 505-|im nets, increased sample density of larger larvae in 

 night collections, and changes in sample densities in relation to tidad stage at a station in the lower 

 portion of the Niantic River. Due to the identified sample biases, much of the offshore data collected 

 prior to 1980 could not be used to examine the life history of larval winter flounder. 



15. Based on the abundance and distribution of smaller larvae, spawning primarily occurred in the Niantic 

 River. larvae were gradually flushed into Niantic Bay, where larger larvae dominated. The spatial 

 distribution of larvae within the Niantic River varied from year to year, but generally smaller larvae 

 were more prevalent in the upper portion of the river and larger larvae in the lower. The lion's mane 

 jellyfish was identified as an important predator of larval winter flounder. 



16. Examination of otoliths from field-collected and laboratory-reared winter flounder larvae indicted that 

 daily increments were not visible. Based on the length-frequency distribution, most larval mortality 

 occurred at the time of first feeding (3-4 mm). Transition to the dermersal juvenile stage occurred at 

 about 6-7 mm. 



17. Fight tidal export-import studies were conducted at the mouth of the Niantic River during 1983-85. 

 The results showed a net export of 4 mm and smaller winter flounder larvae and a net import of 5 

 mm and larger larvae. Larvae with developed fm rays migrated vertically in response to tidal currents 

 to reenter the Niantic River and those within the river demonstrated a similar behavior as a retention 

 mechanism. 



18. Abundance of post-larval young-of-the-year peaked in mid-.Iune and stabilized by late July. Young 

 were most numerous in the lower river during 1983, with similar densities found during 1984 and 1985. 



120 



