Population Estimates 



The annual population sizes from 1975-81 are presented by month in 

 Table 7. The total population size (initial population size Ni + recruits 

 Bi) ranged from 16,506 (1978) to 29,697 (1976). Highest recruitment 

 occurred in June, reflecting the spring molt. The maximum population 

 estimate occurred in July, but as fishing pressure increased in the late 

 summer, population estimates decreased. 



Since our estimates are comprised of mostly sublegal size classes, 

 not affected by commercial fishing, and since inshore lobsters are 

 apparently nonmigratory, low population estimates in late summer and 

 early fall were most likely due to the decreased catchability of lobsters 

 associated with decreasing water temperature. 

 Entrainment 



From 1976 - 1981, the number of lobster larvae counted in entrainment 



and offshore ichthyoplankton samples ranged from 19 (1977) to 71 (1978) . 



3 3 

 Densities ranged from .002/m - .07/m and the majority of larvae were 



stage 1 (88%). The larvae were found in our area from May to July with 



peak abundance occurring in June. If these densities were extrapolated 



based on total flow rates with both units operating 100% during the 



period larvae are found, the number of lobster larvae entrained would be 



high. However, we believe this method of estimation is inappropriate 



since the present sampling technique is not designed to sample lobster 



larvae. Generally more lobster larvae were found in night samples and 



no correlations were found with tidal stages. Knowledge of larval 



distribution is limited (Cooper and Uzmann 1980). Lund and Stewart 



(1970) indicated that the major source of larvae in LIS comes from the 



western portion of the Sound; this correlates well with the number and 



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