Post-larval stage 



Abundance (age 0) 



Post-larval young-of-the-year winter flounder were collected using a 1-m beam trawl from late May 

 through September of 1983-85 at stations LR and CO or WA in the Niantic River. By design, nets of 

 four increasing mesh sizes (0.8 to 6.4 mm) and increasing tow lengths (50 to 100 m) were used to maximize 

 efTiciency in catching young as they grew in size and declined in number. The lack of a tickler chain in 

 the beginning of the study in 1983 was subsequently found to have affected catches and resulted in 

 underestimates of abundance for the first 5 wk (NUSCo 1984). Data from that period were not included 

 in the following calculations of abundance or mortality. 



Abundance of young winter flounder peaked in mid-June, most likely when larval recruitment began 

 to be ofi"set by mortality (Fig. 24). Catches tended to stabilize by July and appeared to fluctuate about 

 mean levels for the remainder of the season. Although densities for the first month were not known with 

 certainty, young at LR were probably initially more numerous in 1983 than in 1984 or 1985, based on 

 abundance later in the year. This follows the pattern of Stage 4 larval abundance given above (Fig. 14). 

 More variability was also evident for 1983 as only three replicate tows were taken per sampling trip rather 

 than the four made during 1984 and 1985. Densities at CO in 1983 were initially quite high, but quickly 

 fell to levels similar to LR by late June. SampUng at CO was hampered by the buildup of dense mats 

 of Enteromorpha clathrata, a filamentous alga. This station was dropped in favor of WA in mid- 1984. 

 Catch at WA was also more variable than LR, but densities appeared to be higher there than in the lower 

 river. 



Growth and mortality (age 0) 



Growth of young was illustrated by changes in weekly mean length (Fig. 25). Less variability was 

 seen in growth than abundance, especially at LR, with relatively small 95% confidence intervals found. 

 Most variation occurred at CO in 1983 with a large group of smaller individuals clustered about one mode 

 joined each week by a few larger specimens. Growth was significantly greater at LR than upriver at CO 

 or WA after mid-June. After a relatively rapid increase from about 12 to 50 mm from May through July, 

 further growth occurred at a slower rate throughout the remainder of summer with little or no increase in 

 weekly means during September. 



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