the power to detect differences in densities of the winter flounder. 



Length frequency comparisons between the discharge and station 5 

 were again made in 1980. The data further suggested real differences in 

 behavior of winter flounder larvae between day and night resulting in 

 changes in vertical distribution of large larvae (NUSCo 1981a) . To 

 improve the number of samples and comparibility between stations 2 and 

 5, sampling effort at the former was increased to four day and night 

 weekly samples from March through early June. Improved estimates of 

 density and catch curves at station 2 resulted. 



Catch curves were used to provide information on larval mortality, 

 which is discussed in more detail below. The data from 1974 and 1975 

 from station 1 produced reasonable catch curves, and monitoring was 

 resumed there in 1981 and 1982; effort was divided equally between 

 stations 1 and 2. One replicate bongo tow was made during the day and 

 one at night from March through May and sampling at stations 5 and the 

 discharge remained as before. The densities of larvae found in 1981 

 suggested that an early spawn in the Niantic River influenced the density 

 of larvae offshore (NUSCo 1982). The unexpected high densities of 6 to 

 8-mm larvae found at Station 5 and the discharge each year (Figs. 9, 10) 

 may have been the result of a second source of larger larvae or from a 

 later, more rapidly growing cohort from the Niantic River which super- 

 imposed their densities over the intital River cohort. A second source 

 of larvae was believed to be a more likely explanation for the relative 

 increase of large larvae noted during several years. 



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