Silversides were trawled primarily (93%) from four stations (NR, JC, IN, 

 NB; Table 3), but were seined primarily (80%) from JC. Seined, trawled 

 and impinged silversides had pronounced seasonal patterns of abundance 

 (Table 4) . They were found in the shore zone primarily from June 

 through October and in trawls and impingment from November through May. 

 Young-of-the-year (20-50 mm) silversides dominanted summer seine catches 

 while adult fish (60-120 mm) were abundant in the trawl and impingement 

 collections (Fig. 10). 



500 1 000 1 500 2000 2SO0 a 

 FREQUENCY 



400 800 

 FREQUENCY 



1 000 2900 



FREQUENCY 



Figure 10. Length frequency of Menidia spp. in seine (left), impingement 

 (middle) and trawl (right) collections from October 1976 

 through September 1983. 



Fluctuations in log-transformed catches were modeled for several 

 monitoring programs (Table 8) . Only one model (JC) had a significant 

 long-term ( >12 mo) harmonic component (3-yr) . All seine and trawl 

 models had a 6-mo cycle and some also had 4- and 3-mo cycles. 

 Impingement models included flow and 12-mo harmonic components and 

 realistically described fluctuations of impinged silversides. Forecast 

 error for the 1983 data was low at Unit 2 (18%); Unit 1 forecast error 

 was higher (39%). Most of the 1983 data fell within the 95% confidence 



23 



