314 
Fishery Bulletin 115(3) 
Table 4 
Summary statistics for the average proportion of change (shown in Fig. 7) in performance metrics used to evaluate the ef- 
fect of closure location rule 1 on the Atlantic surfclam ( Spisula solidissima ) population and on the commercial fishery in 
the Mid-Atlantic Bight. Rule 1 mandates that the cell with the highest ratio of the number of small clams to the number of 
market-size clams be closed each year. Size of clams is given as shell length (SL) in millimeters, closure duration is measured 
in years, and LPUE means landings per unit effort. N is the number of simulations where a significant difference exists 
between the performance metric under present-day or alternative management at present-day abundance. The maximum 
iVis 9. 
Definition of a small clam 
104 mm SL 
93 
mm 
SL 
80 mm SL 
64 mm 
SL 
Closure duration (yr) 
3 
5 
7 
3 
5 
7 
3 
5 
7 
3 
5 
7 
Stock density 
Present management 
N 
4 
4 
1 
2 
1 
0 
2 
1 
1 
3 
2 
5 
X 2 
0.04 
0.05 
0.10 
0.04 
0.05 
- 
0.08 
0.02 
0.01 
0.05 
0.03 
0.04 
Min 
0.01 
0.02 
- 
0.04 
- 
- 
0.07 
- 
- 
0.04 
0.03 
0.02 
Max 
0.08 
0.08 
- 
0.05 
- 
- 
0.08 
- 
- 
0.05 
0.04 
0.06 
Alternative management 
N 
4 
3 
6 
3 
6 
4 
5 
5 
4 
2 
3 
3 
X 2 
0.04 
0.03 
0.06 
0.06 
0.04 
0.08 
0.04 
0.04 
0.09 
0.10 
0.04 
0.06 
Min 
0.02 
0.02 
0.04 
0.03 
0.02 
0.03 
0.02 
0.02 
0.04 
0.03 
0.03 
0.05 
Max 
0.07 
0.05 
0.09 
0.08 
0.10 
0.12 
0.08 
0.10 
0.14 
0.17 
0.05 
0.06 
Number of clams per bushel 
Present management 
N 
5 
9 
9 
2 
9 
9 
2 
9 
9 
2 
9 
9 
X 2 
0.01 
0.03 
0.04 
0.01 
0.03 
0.04 
0.01 
0.02 
0.04 
0.01 
0.01 
0.03 
Min 
0.01 
0.02 
0.03 
0.01 
0.02 
0.03 
0.01 
0.01 
0.03 
0.01 
0.01 
0.02 
Max 
0.02 
0.04 
0.07 
0.01 
0.04 
0.06 
0.01 
0.03 
0.06 
0.01 
0.02 
0.05 
Alternative management 
N 
v 2 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
X 
Min 
Max 
LPUE 
Present management 
N 
0 
1 
1 
0 
0 
1 
0 
1 
1 
0 
0 
1 
X 2 
- 
0.04 
0.05 
- 
- 
0.02 
- 
0.05 
0.04 
- 
- 
0.02 
Min 
- 
Max 
Alternative management 
N 
4 
3 
5 
6 
7 
4 
7 
7 
3 
5 
8 
4 
X 2 
0.06 
0.05 
0.06 
0.07 
0.08 
0.12 
0.05 
0.08 
0.12 
0.07 
0.07 
0.09 
Min 
0.02 
0.04 
0.04 
0.04 
0.03 
0.06 
0.02 
0.05 
0.09 
0.02 
0.02 
0.06 
Max 
0.07 
0.06 
0.10 
0.20 
0.16 
0.21 
0.14 
0.13 
0.17 
0.18 
0.11 
0.15 
Number of 10' squares fished 
Present management 
N 
4 
5 
6 
3 
4 
5 
4 
5 
4 
4 
4 
5 
X 2 
0.03 
0.04 
0.07 
0.03 
0.04 
0.06 
0.03 
0.05 
0.06 
0.04 
0.04 
0.07 
Min 
0.02 
0.02 
0.05 
0.02 
0.04 
0.05 
0.02 
0.02 
0.03 
0.02 
0.04 
0.05 
Max 
0.05 
0.06 
0.09 
0.03 
0.05 
0.08 
0.04 
0.08 
0.09 
0.10 
0.05 
0.10 
Alternative management 
N 
2 
0 
1 
1 
0 
0 
1 
0 
0 
3 
0 
0 
X 2 
0.04 
- 
0.08 
0.06 
- 
- 
0.06 
- 
- 
0.07 
- 
- 
Min 
0.04 
- 
- 
- 
- 
- 
- 
- 
- 
0.05 
- 
- 
Max 
0.06 
- 
- 
- 
- 
- 
- 
- 
- 
0.09 
- 
- 
Total distance traveled 
Present management 
N 
1 
0 
0 
1 
0 
0 
0 
1 
0 
1 
0 
0 
X 2 
0.03 
- 
- 
0.03 
- 
- 
- 
0.03 
- 
0.05 
- 
- 
Min 
- 
Max 
Alternative management 
N 
3 
5 
7 
1 
4 
6 
3 
4 
4 
2 
4 
4 
X 2 
0.03 
0.04 
0.04 
0.04 
0.04 
0.05 
0.04 
0.04 
0.05 
0.03 
0.03 
0.05 
Min 
0.03 
0.03 
0.03 
- 
0.02 
0.02 
0.04 
0.02 
0.03 
0.02 
0.02 
0.03 
Max 
0.04 
0.05 
0.07 
- 
0.07 
0.06 
0.05 
0.04 
0.08 
0.03 
0.05 
0.08 
