Probably the greatest potential impact to the 

 tautog from three-unit operations is from the en- 

 trainment of eggs. The entrainment estimate for 

 1986 was at least twice that of previous years 

 (Table 21). The Gompertz function was fitted to 

 the annual cumulative egg densities at EN (all R 

 values exceeded 0.98) and the a parameter was 

 used to compare abundances. Annual egg abun- 



TABLE 21. Annual entrainment estimates and 95% confi- 

 dence intervals for tautog eggs at MNPS. 



Revised estimate due to error in previous calculations 

 (NUSCO 1987b). 



dance fluctuated from a low in 1979 to relatively 

 high abundances in 1985 and 1986 (Fig. 12). The 

 time of peak abundance (estimated from the in- 

 flection point of Gompertz function) generally 

 occurred mid to late June (Table 22). 



TABLE 22. Estimated date of peak abundance for tautog 

 eggs based on the inflection point of the Gompertz func- 

 tion for station EN. 



Year 



EN 



1979 

 1980 

 1981 

 1982 

 1983 

 1984 

 1985 

 1986 



Jun 23 

 Jun 22 

 Jun 21 

 Jun 28 

 Jun 21 

 Jun 23 

 Jun 17 

 Jun 12 



Tautog larvae did not appear consistently in 

 ichthyoplankton samples during their period of 

 occurrence and when present, occurred in low 

 densities. Due to the numerous zero values for 

 sample densities, larval entrainment estimates, 



32 



24 



20 



16 



79 



82 



83 



84 



85 



YEAR 



Fig. 12. Tautog egg abundance e,stimates and 95% confidence intervals based on the a parameter of tfie Gompertz 

 function for station EN. 



282 



