11-7 



Otter Trawl Sampling 



Monthly otter trawling was conducted at Stations 5, 8, 13, 19 

 and 20 (Figure 11-1) from May 1971 through June 1975 to sample demersal 

 fishes. The trawl used was a 25-ft Marinovich semiballoon otter trawl, 

 with a 1-3/8-in. square mesh body and a 1/4-in. square mesh cod-end 

 liner. Station 11 was added in July 1975 to provide additional infor- 

 mation from the center Harbor area, close to the site of Harbor Station 

 (Figure 11-1), during start-up and subsequent operational periods. At 

 that time, the program was also changed to incorporate paired ten-minute 

 tows at each station instead of the previously employed single ten- 

 minute tow (see Section 8.0) . Within the study period delineated above, 

 April 1973 and January 1977 were the only months during which trawl sam- 

 pling was not conducted (Figure 11-1) . 



Gill Net Sampling 



Monthly gill netting to sample pelagic fishes commenced in 

 June 1971 and was initially carried out only during the warmer months at 

 Stations 5, 8, 13 and 19. The gill nets, 150-ft long and 6-ft deep, 

 were composed of six 25-ft panels of 3/4, 1, 1-1/4, 1-1/2, 2 and 2-1/2 

 inch square mesh nylon. All nets were fished overnight at approximately 

 2-1/2 ft above bottom. 



During April 1975, the gill net program was modified to 1) 

 substitute Station 8A, across the channel from the Harbor Station dis- 

 charge for Station 5, and 2) operate year-round to gain information on 

 the distribution and abundance of Atlantic herring [Clupea harengus) , a 

 winter migrant species. Limited gill net data were collected during 

 January 1977 due to the presence of ice throughout much of the Harbor. 



