The tomcod impingement data were well described (R =0.69; Appendix XXI) by a time-series 

 model. This model had annual and six-month periodic components. A summary of this baseline model 

 is presented in Appendix XXI. 



Myoxocephalus aenaeus, grubby 



The grubby {Myoxocephalus aenaeus) is found in coastal waters, commonly in eelgrass habitats, along 

 the Atlantic coast of North America from the Gulf of St. Lawrence to New Jersey (Bigelow and Schrocder 

 1953). It spawns throughout the winter (Lund and Marcy 1975) and Richards (1959) reported finding 

 larvae in shallower areas of LIS from February to April. The grubby tolerates a wide range of temperatures 

 and salinities (Bigelow and Schroeder 1953). 



The grubby is a resident of the waters near MNPS and both larvae and adults have been collected 

 in the NUSCo monitoring programs. Eggs were rarely collected because they are demersal and adhesive. 

 Adult fish were also rare in seine samples. 



Overall mean larval density of grubby during the two-unit operational period ranked fourth at EN 

 and sixth at NB (Appendices VI and VII). These larvae were collected from February through May at 

 both stations (Fig. 18). Annual entrainment estimates ranged from 9x10 in 1978 to 50x10 in 1983 and 

 peak larval abundance, as measured by both median (Table 9) and mean densities (Tables 10 and 12), 

 occurred in 1981. However, the temporal pattern described by the annual means and medians did not 

 correspond to the pattern described by the cumulative mean densities shown in Figure 18. Cumulative 

 density at NB was highest in 1985, followed by 1981, 1983 and 1982, while at EN it was highest in 1981, 

 followed by 1982, 1983 and 1985. Most likely, these discrepancies were not related to any real differences 

 but were a result of of the high variablity inherent of the plankton data (variances were 20 to 200 limes 

 larger than the corresponding means). 



Over 90% of the grubby in the impingement and trawl samples were adults (60 to 120 mm) (Fig. 

 19). Adult catches ranked fourth among impinged taxa and ninth among species taken in trawls (Appendices 

 IX and X). Impingement estimates ranged from 2,108 in 1976 to 14,634 in 1983, and 42% of the total 

 impingement during the two-unit operational period (1976-1985) occurred in 1980 and 1983. The 



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