to assist in the generation and interpretation of the entrainment impact 

 predictive models. The objectives of the offshore program (Sissenwine 

 et al. 1973) were to determine: 1) the seasonal succession of the 

 plankton community; 2) the spatial and temporal onset of spawning of 

 important fish species; 3) the fish larvae and egg concentrations at the 

 model boundaries; 4) the larval mortality rate of selected fish species; 

 5) larval concentration for model verification; 6) and whether estimates 

 of the total production of fish eggs and larvae were compatible with 

 adult population estimates. Winter flounder was chosen as the primary 

 subject species for study. 



Combinations of stations 1-16 (Figure 4) were sampled from 1973 

 through 1975 with various sampling frequencies, tow types (surface, 

 bottom, oblique), net types (0.505 mm-mesh, 0.333-mm mesh) and times 

 (day, night) (NUSCo 1976). Stations 1-10 were sampled in 1973, with the 

 addition of stations 11-13 in 1974 and 14-16 in 1975. Stations 11-16 

 were added with the intent of better estimating the near-shore distribution 

 of larvae (or those on the model boundary) . 



Comparison of Offshore and Entrainment Sampling 



Studies were conducted in 1973 to determine the catch comparability 

 of the offshore sampling net (0.333-mm-mesh, 60-cm mouth, General Oceanic 

 flow meter) to the entrainment sampling net (0.333-mm-mesh 100-cm mouth 

 TSK flow meter) and Battelle and WHOI laboratory processing techniques 

 (Sissenwine et al. 1973). Towing velocities of 25, 75, and 125 cm/sec 

 were considered for both net types. Samples from both net types were 

 processed by each group (Battelle and WHOI) . Results from processing 

 and analysis of more than 100 samples indicated there was no significant 



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