Fig. 1. Location of the Millstone Nuclear Power Station (MNPS) and the three lobster sampling stations (•). 



lobsters, severely injured or newly molted (soft) 

 lobsters, and those < 55 mm CL were released 

 untagged after recording the above data. 



Beginning in 1981, data were collected to deter- 

 mine the size at which females become sexually 

 mature by measuring the maximum outside width 

 of the second abdominal segment of all females 

 to the nearest millimeter. Female size at sexual 

 maturity was estimated by calculating the ratio of 

 the abdominal width to the carapace length and 

 plotting that ratio against the carapace length 

 (Skud and Perkins 1969; Krouse 1973). 



Catch per unit effort (CPUE), calculated as the 

 number of lobsters caught per pothaul was aver- 

 aged by computing the arithmetic mean. Because 

 the CPUE data are ratios, they are not additive 

 and have an asymmetric distribution about the 

 arithmetic mean. Therefore, we computed the 

 geometric mean which is the best statistic for con- 



structing asynmietric confidence intervals for log- 

 normal data (Snedecor and Cochran 1967). Since 

 1984, in addition to counting the number of lob- 

 sters caught in each pot we counted the number 

 of other organisms caught, to examine the influ- 

 ence of competing species on lobster catch. The 

 amount of time between pothauls (soaktime or 

 sct-over-days) also influences lobster catch, and 

 CPUE data are weighted to account for varying 

 soaktimes. As a result, catch per unit effort was 

 adjusted by covariance analysis for the effect of 

 soaktime and the catch of competing species that 

 significantly affected CPUE. 



Methods for the collection of lobsters on the 

 intake traveling screens are described in the Fish 

 Ecology section of this report under Methods and 

 Materials- Impingement. In December 1987, 

 based on historical impingement data collected 

 since 1972, NUSCO and the CT DEP agreed to 



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