rescaJed by a factor of 7 because the cumulative densities were based on weekly means and thus accounted 

 for a 7-d period. Time of peak abundance was estimated as the date t{ corresponding to the inflection 

 point of the cumulative function defmed by its parameters P and k as: 



^. = -f- (8) 



Least-squares estimates and asymptotic 95% confidence intervals for these parameters were obtained by 

 fitting Equation 6 to the cumulative abundance data using nonlinear regression methods (SAS Institute 1985). 



The cumulative Gompertz function was used to examine temporal and spatial distribution of larval 

 winter flounder from data collected in the 1974-75 offshore study, entrainment sampling in 1976-85, and 

 special larval winter flounder sampling in 1981-85. The stations sampled during 1974 and 1975 were 

 grouped in relation to their location to the Niantic River: Niantic River (1 and 2); mouth of the Niantic 

 River (3, 4, 15, and 16); mid-Niantic Bay (5, 11, and 12); Jordan Cove (6 and 13); Twotree Island Charmel 

 (7 and 8); and Offshore (9, 10, and 14). 



Time-based harmonic regression models were also used with abundance data from station 5 in Niantic 

 Bay (1979-85) and the entraioment sampling station EN (1976-85) to describe fluctuations in abundance 

 (see Fish Ecology section for detailed methods). 



Special studies 



The only station in the Niantic River with strong tidal currents was C. To determine the effect of 

 tidal currents on sample densities of larvae, 24-h studies were conducted in 1983 and 1984. Samples were 

 collected at 2-h intervals over a 24-h period on April 28 and May 9 in 1983 and March 12 and March 19 

 in 1984. Tow duration was 15 min with paired 333-^lm mesh nets in 1983 and 6 min with paired 202- 

 and 333-}jm mesh nets in 1984. These data were examined to determine if tidal currents caused sample 

 density biases. 



Larval import and export studies were conducted at the mouth of the of the Niantic River from 1983 

 through 1985. Stationary tows were taken by mooring the boat to the Niantic River Highway Bridge in 

 the middle of the channel. Bongo samplers were deployed off each side of the boat with one at mid-water 



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