| CRD 03-14
Table 16. Example of the spreadsheet calculations for estimating
semi-annual discarded witch flounder in the large-mesh otter trawl fishery.
This spreadsheet illustrates 1993, quarters 1 and 2 with the NEFSC spring
survey. The bold numbers indicate columns and the mathematical
operation performed. |
| 1993 Landings from Q1+Q2 and 1993 spring survey |
Length
(cm)
|
1 |
2 |
3=1*2 |
4 |
5=3*4 |
6=3-5 |
7 |
8=6*factor |
Survey
No/tow |
140 mm
Prop.
Retained |
Survey
Retained |
Prop
Kept |
Survey
Kept |
Survey
Discarded |
100's
Numbers
Landed |
units
Numbers
Discarded |
| 1 |
0.000 |
0.00005 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
0 |
| 3 |
0.000 |
0.00008 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
0 |
| 5 |
0.034 |
0.00015 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
34 |
| 7 |
0.064 |
0.00028 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
120 |
| 9 |
0.051 |
0.00051 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
174 |
| 11 |
0.000 |
0.00092 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
0 |
| 13 |
0.000 |
0.00168 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
0 |
| 15 |
0.011 |
0.00305 |
0.0000 |
0.00 |
0.0000 |
0.0000 |
0 |
224 |
| 17 |
0.067 |
0.00554 |
0.0004 |
0.00 |
0.0000 |
0.0004 |
0 |
2483 |
| 19 |
0.042 |
0.01005 |
0.0004 |
0.00 |
0.0000 |
0.0004 |
0 |
2823 |
| 21 |
0.028 |
0.01816 |
0.0005 |
0.00 |
0.0000 |
0.0005 |
0 |
3401 |
| 23 |
0.042 |
0.03261 |
0.0014 |
0.00 |
0.0000 |
0.0014 |
0 |
9161 |
| 25 |
0.061 |
0.05787 |
0.0035 |
0.00 |
0.0000 |
0.0035 |
0 |
23612 |
| 27 |
0.165 |
0.10065 |
0.0166 |
0.00 |
0.0000 |
0.0166 |
0 |
111083 |
| 29 |
0.079 |
0.16938 |
0.0134 |
0.00 |
0.0000 |
0.0134 |
0 |
89503 |
| 31 |
0.205 |
0.27091 |
0.0555 |
0.01 |
0.0006 |
0.0550 |
0 |
367759 |
| 33 |
0.165 |
0.40372 |
0.0666 |
0.10 |
0.0067 |
0.0600 |
231 |
401011 |
| 35 |
0.152 |
0.55231 |
0.0840 |
0.99 |
0.0831 |
0.0008 |
2519 |
5615 |
| 37 |
0.076 |
0.69211 |
0.0526 |
1.00 |
0.0526 |
0.0000 |
4892 |
0 |
| 39 |
0.042 |
0.80377 |
0.0338 |
1.00 |
0.0338 |
0.0000 |
3984 |
0 |
| 41 |
0.050 |
0.88184 |
0.0441 |
1.00 |
0.0441 |
0.0000 |
3143 |
0 |
| 43 |
0.000 |
0.93150 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
1699 |
0 |
| 45 |
0.000 |
0.96121 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
1658 |
0 |
| 47 |
0.000 |
0.97833 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
1293 |
0 |
| 49 |
0.054 |
0.98799 |
0.0534 |
1.00 |
0.0534 |
0.0000 |
1268 |
0 |
| 51 |
0.046 |
0.99337 |
0.0457 |
1.00 |
0.0457 |
0.0000 |
1225 |
0 |
| 53 |
0.000 |
0.99635 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
812 |
0 |
| 55 |
0.018 |
0.99799 |
0.0180 |
1.00 |
0.0180 |
0.0000 |
486 |
0 |
| 57 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
354 |
0 |
| 59 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
198 |
0 |
| 61 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
72 |
0 |
| 63 |
0.019 |
1.0000 |
0.0190 |
1.00 |
0.0190 |
0.0000 |
27 |
0 |
| 65 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
4 |
0 |
| 67 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
0 |
0 |
| 69 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
0 |
0 |
| 71 |
0.000 |
1.0000 |
0.0000 |
1.00 |
0.0000 |
0.0000 |
0 |
0 |
| TOTAL |
1.471 |
|
0.5088 |
|
0.3568 |
0.1520 |
2,386,500 |
1,017,003 |
|
Factor = 6,688,621 |
|
| 1: From SURVAN, stratified mean number per tow at length. |
(col 7/ col 5) |
| 2: From LOGEST Program using 140 mm mesh in 1993 from adjusted 130-d mm from Walsh et al. (1992) for Am plaice |
| 4: knife-edge at 36 cm |
| 7: From Length BIOSTAT |
|
|