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Fishery Bulletin 115(3) 
Closure duration (years) 
Definition of a small clam (mm SL) 
Figure 8 
The proportion of change in performance metrics used to evaluate the effect of clo- 
sure location rule 2 on the Atlantic surfclam ( Spisula solidissima ) population and 
commercial fishery in the Mid-Atlantic Bight averaged for all simulations where a 
significant difference between present-day and alternative management exists (see 
Table 6 for the fraction of total simulations used to generate each bar value and 
Table 8 for summary statistics). Rule 2 mandates that the cell with the highest 
density of small clams (number of clams per square meter) be closed each year. Bars 
in the positive region represent proportional differences under alternative man- 
agement. Proportional differences under present-day management are represented 
in negative values for clarity. The metric of landings per unit of effort (LPUE) is 
the number of bushels per hour, and definitions of a small clam are given as shell 
length (SL) in millimeters. 
