Mediterranean Swordfish catches
25000
20000
15000
t.
Other gears
LL
10000
5000
0
1950
1956
1962
1967
1972
1977
1982
1987
1992
1997
2002
year
Figure 1. Cumulative estimates of swordfish catches (t) in the Mediterranean by major gear type, 1950-2005.
Figure 2. Map of the Mediterranean Sea with the locations referred to in the Report. The
Mediterranean/Atlantic boundary used by ICCAT is at 5ºW longitude. The approximate provincial
administrative limit for the Mediterranean used by Morocco is also shown.
1008
3.0
Relative CPUE
2.5
2.0
1.5
1.0
0.5
0.0
1974
1979
1984
1989
1994
1999
2004
Year
Figure 3. The relative CPUE time series used in production modeling, which results from the combined
information in the Italian longline, Greek longline, Spanish longline, Japanese longline, Moroccan gillnet,
and Italian gillnet time series.
Observed
B=.75K in 1968
B=K in 1950
Est B in 1950
3.5
3.0
CPUE
2.5
2.0
1.5
1.0
0.5
0.0
1975
1985
1995
2005
Year
Figure 4. Fits of the three productions models (ASPIC) with different model structures to the observed
CPUE data.
1009
5.0
4.5
4.0
F/FMSY
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0.0
0.0
0.5
1.0
1.5
2.0
B/BMSY
Figure 5. Scatter of stock status results for 2005 from 1500 bootstrap results using three model
formulations (ASPIC, see Appendix 4) for the Mediterranean swordfish. The median outcome is indicated
as the large closed circle in the center of the distribution of points.
2.0
1.5
F/FMSY
2005
1.0
0.5
1968
0.0
0.0
0.5
1.0
1.5
2.0
B/BMSY
Figure 6.a. The median estimated trajectory of B- and F-ratios expressed relative to MSY for the period
1968-2005. The results are amalgamated from the three production model scenarios described in the
Appendix 4.
1010
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
1965
B/BMSY
F/FMSY
1975
1985
1995
2005
Figure 6.b. The time trajectory of estimated median relative biomass and relative F starting from 1968
based on the combined bootstrap outcomes of the ASPIC production model.
1011
2.0
B/BMSY
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
1988
2.0
1.8
1993
1998
2003
1998
2003
F/FMSY
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
1988
1993
Figure 7. Estimates of B/BMSY (upper plate) and F/FMSY (lower plate) with associated 80% bootstrap
confidence limits (dashed lines) based on the combined bootstrap outcomes of the ASPIC production
model.
1012
Figure 8. Observed abundance indices and model fitted line based on the predicted indices, for the TSM
production model.
Figure 9. Relative biomass and catch rate estimates from the TSM production model.
1013
Figure 10. Estimated catchability residuals by fleet from the XSA model.
1014
0.70
0.60
0.50
F
0.40
0.30
0.20
0.10
20
05
20
03
20
01
19
99
19
97
19
95
19
93
19
91
19
89
19
87
19
85
0.00
Year
Figure 11. Mean Fs (ages 2-5) by year estimates obtained with the XSA model.
70000
Biomass (tons)
60000
50000
40000
TB
SSB
30000
20000
10000
05
20
03
20
01
20
99
19
97
19
95
19
93
19
91
19
89
19
87
19
19
85
0
Year
Figure 12. Total (TB) and spawning stock biomass (SSB) estimates obtained with the XSA model.
1.5
0.6
JPN LL
0.6
GRE LL
0.4
1
0
-0.21980
0.5
0
1980
-0.5
ITA LL
0.4
0.2
1985
1990
1995
2000
2005
2010
0.2
1985
1990
1995
2000
2005
2010
-0.4
-0.6
0
1980
-0.2
1985
1990
1995
2000
2005
2010
2000
2005
2010
-0.4
-0.8
-1
-0.6
-1
-1.5
-1.2
1
-0.8
0.2
ESP LL
0.8
0.5
MAR GN
0.3
0.6
0.2
0.1
0.4
0.2
0
1980
-0.2
-0.4
-0.6
ITA GN
0.4
0.15
0.1
0
-0.11980
0.05
1985
1990
1995
2000
2005
2010
0
1980
-0.05
1985
1990
1995
-0.2
1985
1990
1995
2000
2005
2010
-0.3
-0.4
-0.5
-0.1
-0.6
Figure 13. Fits to the available CPUE indices obtained using VPA-2Box, in log scale. The diamonds are
the observed data and the squares connected with a line are the predicted ones.
1015
1.2
JPN LL
1
0.8
0.8
0.8
0.4
0.6
0.4
0.2
0.2
0
0
0
2
4
1.2
6
8
10
Index sel.
1
0.6
12
0.6
0.4
0
2
4
1.2
ESP LL
6
8
10
12
0
1
0.8
0.8
0.8
0.6
0.4
0.2
0.2
0
0
0
2
4
6
8
10
Index sel.
1
0.4
12
2
4
1.2
MAR GN
1
0.6
ITA LL
0.2
0
Index sel.
Index sel.
1.2
GRE LL
1
Index sel.
Index sel.
1.2
6
8
10
12
ITA GN
0.6
0.4
0.2
0
0
2
4
6
8
10
12
0
2
4
6
8
10
12
Figure 14. Estimated selectivities at age for each index used in the VPA-2Box analyses.
1600000
1200000
N age 0
1400000
1200000
1000000
N age 2
700000
600000
800000
800000
600000
400000
200000
0
1980
800000
N age 1
1000000
500000
600000
400000
300000
400000
200000
200000
1985
1990
400000
1995
Year
2000
2005
2010
100000
1985
1990
250000
N age 3
350000
0
1980
1995
Year
2000
2005
2010
1985
1990
140000
N age 4
1995
Year
2000
2005
2010
2000
2005
2010
2000
2005
2010
N age 5
120000
200000
300000
0
1980
100000
250000
150000
80000
100000
60000
200000
150000
40000
100000
50000
20000
50000
0
1980
1985
1990
70000
1995
Year
2000
2005
2010
1985
1990
30000
N age 6
60000
0
1980
1995
Year
2000
2005
2010
1985
1990
14000
N age 7
1995
Year
N age 8
12000
25000
50000
0
1980
10000
20000
40000
8000
15000
6000
30000
10000
20000
10000
0
1980
2000
0
1985
1990
10000
9000
8000
7000
6000
5000
4000
3000
2000
1000
0
1980
4000
5000
1995
Year
2000
2005
2010
1980
1985
1990
16000
N age 9
1995
Year
2000
2005
2010
2005
2010
0
1980
1985
1990
1995
Year
N age 10+
14000
12000
10000
8000
6000
4000
2000
1985
1990
1995
Year
2000
2005
2010
0
1980
1985
1990
1995
Year
2000
Figure 15. Estimated populations sizes at age for Mediterranean swordfish obtained with the VPA-2Box
analyses.
1016
45000
40000
Biomass (t)
35000
30000
25000
20000
15000
10000
Spawning Bio
5000
Exploitable Bio
0
1980
1985
1990
1995
Year
2000
2005
2010
Figure 16. Estimated spawning and exploitable biomass for Mediterranean swordfish obtained with the
VPA-2Box analyses.
0.7
F
0.6
0.5
0.4
0.3
0.2
0.1
0
1980
1985
1990
1995
2000
2005
2010
Year
Figure 17. Estimated fishing mortality rates for Mediterranean swordfish obtained with the VPA-2Box
analyses.
1985-89
1990-94
1995-99
2000-04
1.2
Selectivity
1
0.8
0.6
0.4
0.2
0
0
2
4
6
8
10
Age
Figure 18. Estimated selectivity patterns for Mediterranean swordfish obtained with the VPA-2Box
analyses, by 5-year blocks.
1017
N age 0
1600000
1400000
1200000
1000000
800000
600000
400000
200000
0
1980
1985
1990
1995
2000
2005
2010
Year
age0_VPA
age0_XSA
F 2+
F1
0.7
0.3
0.6
0.25
0.5
0.2
0.4
0.15
0.3
0.1
0.2
0.05
0.1
0
1980
1985
1990
1995
2000
2005
0
1980
2010
1985
1990
Year
F 2+_vpa
F 2+_xsa
F 1_vpa
F0
0.045
0.04
0.035
0.03
0.025
0.02
0.015
0.01
0.005
0
1980
2000
2005
2010
2005
2010
2005
2010
F 1_xsa
F5
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
1985
1990
1995
2000
2005
2010
0
1980
1985
1990
Year
F 0_vpa
1995
2000
Year
F 0_xsa
F 5_vpa
F7
F 5_xsa
F9
0.9
0.8
0.7
0.8
0.7
0.6
0.6
0.5
0.4
0.3
0.2
0.1
0
1980
1995
Year
0.5
0.4
0.3
0.2
0.1
1985
1990
1995
2000
2005
2010
Year
F 7_vpa
0
1980
1985
1990
1995
2000
Year
F 7_xsa
F 9_vpa
1018
F 9_xsa
SSB
40000
35000
30000
25000
20000
15000
10000
5000
0
1980
1985
1990
1995
2000
2005
2010
2005
2010
Year
SSB_vpa
SSB_xsa
Total Biomass
70000000
60000000
50000000
40000000
30000000
20000000
10000000
0
1980
1985
1990
1995
2000
Year
totBio_vpa
totBio_xsa
Figure 19. Comparison of some results obtained with two different age-structured assessment methods
applied to Mediterranean swordfish. Top: Recruitment; Middle: Fishing mortality at age. Bottom:
Spawning biomass (t) and total biomass (kg).
1019
20000
18000
Equilibrium Yield (t)
16000
14000
12000
10000
8000
6000
4000
2000
0
0
0.2
Fmax
0.4
F2005
0.6
0.8
1
1.2
1.4
Fishing mortality
Figure 20a. Equilibrium yield – F relationship for Mediterranean swordfish based on VPA-2box (scaled
assuming a level of recruitment of 1,059,533 fish).
20000
18000
Equilibrium Yield (t)
16000
14000
12000
10000
8000
6000
4000
2000
0
0
0.2
0.4
0.6
0.8
1
1.2
1.4
Fishing mortality
Figure 20b. Equilibrium yield – F relationship for Mediterranean swordfish based on XSA (scaled
assuming a level of recruitment of 1,059,533 fish).
1020
2.5
VPA
F/Fmax
2
1.5
1
0.5
0
0
0.5
1
1.5
2
SSB/SSBmax
2.5
XSA
F/Fmax
2
1.5
1
0.5
0
0
0.5
1
1.5
2
SSB/SSBmax
Figure 21. Trends in the estimated ratios of fishing mortality relative to the F that maximizes yield per
recruit (Fmax) against the estimated ratios of spawning biomass relative to the level that would result from
fishing at Fmax. Top: VPA-2Box results. Bottom: XSA results. The large open circles indicate the position
of the 2005 data point.
1021
1
1
Figure 22. The range of bootstrap outcomes from the VPA-2BOX status evaluations. The large, closed
circle represents the deterministic outcome. Although the uncertainty in the outcomes is high, all of the
estimates indicate the stock is overfished and undergoing overfishing
1022
B/BMSY
10,000 t
12,000 t
MSY
16,000 t
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
2000
2005
2010
2015
Figure 23a. Forecasts of B/BMSY for the different constant catch scenarios shown based on the combined
bootstrap outcomes from the ASPIC production model. The lines with symbols represent median outcomes.
The assumed constant catch for the MSY scenario was 14,300 t. The confidence interval reflects the upper
80% bound for the 10,000 t scenario and the lower boundary is that from the 16,000 t scenario.
2.00
B/BMAX
10,000 t
12,000 t
14,300 t
16,000 t
1.80
1.60
B/BMAX
1.40
1.20
1.00
0.80
0.60
0.40
0.20
0.00
2000
2005
2010
2015
Year
Figure 23b. Forecasts of B/BMAX (BMAX is a proxy for BMSY) for the different constant catch scenarios
shown based on the combined bootstrap outcomes from the VPA-2BOX model. The lines with symbols
represent median outcomes. The confidence interval reflects the upper 80% bound for the 10,000 t scenario
and the lower boundary is that from the 16,000 t scenario.
1023
Figure 24. From left to right and top to bottom: Box-whisker plots by year, for the total catch (weight),
juvenile catch (weight), juvenile catch (number) and juvenile catch ratio (number) estimates obtained from
the VPA Scenario 1 simulations. Solid circles indicate the corresponding reported rates for the years 20002005.
1024
Figure 25. From left to right and top to bottom: Box-whisker plots by year, for the total catch (weight),
juvenile catch (weight), juvenile catch (number) and juvenile catch ratio (number) estimates obtained from
the VPA Scenario 2 simulations. Solid circles indicate the corresponding reported rates for the years 20002005.
1025
Figure 26. From left to right and top to bottom: Box-whisker plots by year, for the total catch (weight),
juvenile catch (weight), juvenile catch (number) and juvenile catch ratio (number) estimates obtained from
the VPA Scenario 3 simulations. Solid circles indicate the corresponding reported rates for the years 20002005.
1026
Figure 27. From left to right and top to bottom: Box-whisker plots by year, for the total catch (weight),
juvenile catch (weight), juvenile catch (number) and juvenile catch ratio (number) estimates obtained from
the VPA Scenario 4 simulations. Solid circles indicate the corresponding reported rates for the years 20002005.
1027
Rel. B
Rel F
Scenario1
2.5
F/Fmax or B/Bmax
F/Fmax or B/Bmax
2.5
2
1.5
1
0.5
0
1.5
1
0.5
0
0
5
10
15
20
0
Projection year
2.5
Rel. B
Rel F
Scenario3
2
1.5
1
0.5
5
2.5
F/Fmax or B/Bmax
F/Fmax or B/Bmax
Rel. B
Rel F
Scenario2
2
0
10
Projection year
15
20
Rel. B
Rel F
Scenario4
2
1.5
1
0.5
0
0
5
10
Projection year
15
20
0
5
10
Projection year
15
20
Figure 28. Projections results in terms of fishing mortality and biomass relatives to Fmax and Bmax for the
four VPA scenarios considered.
Figure 29. Median SSB and annual catch levels with the associated 80% confidence limits as predicted by
the seasonal closure scenarios. Estimates refer to the last ten years of the projection period, i.e. after
stabilization.
1028