Assessment of red shrimp (Aristeus antennatus) exploited by the Spanish trawl fishery: in the...
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W orking D ocum entto theG .F.C.M . SAC W orking G roup on D em ersal species R om e 26-30 Septem ber 2005 Assessment of red shrimp (Aristeus antennatus) exploited by the Spanish trawl fishery: in the geographical sub-area Balearic Islands (GSA-5) and Northern Spain (GSA-6)
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Transcript of Assessment of red shrimp (Aristeus antennatus) exploited by the Spanish trawl fishery: in the...
Working Document to the G.F.C.M. SAC Working Group on
Demersal species
Rome 26-30 September 2005
Assessment of red shrimp (Aristeus antennatus) exploited by the Spanish trawl fishery: in the geographical sub-area Balearic Islands (GSA-5) and Northern Spain (GSA-6)
Poblational characteristics
GSA-5 Females
Years
1992 1994 1996 1998 2000 2002 2004
CL
(m
m)
1218243036424854606672
Males
Years
1992 1994 1996 1998 2000 2002 2004
CL
(m
m)
12
16
20
24
28
32
36
40
Females
Years
1996 1998 2000 2002 2004
CL
(mm
)
1218243036424854606672
GSA-6
Males
Years
1996 1998 2000 2002 2004
CL
(mm
)
12
16
20
24
28
32
36
40
Females
10 15 20 25 30 35 40 45 50 55 60 65 70
CLm
50%
0.0
0.5
1.0
Males
CL (mm)
10 15 20 25 30 35 40
CLm
50%
0.0
0.5
1.0
Box-plot figures Size at first maturity
Females
0
1020
30
4050
60
1 2 3 4
Ages
CL
mm
Von Bertalanffy growth curves
Males
0
10
20
30
40
1 2 3 4
Ages
CL
mm
Females
0
20
40
60
80
1 2 3 4 5 6 7 8
Age
CL
(mm
)
Males
0
10
20
30
40
1 2 3 4 5 6 7Age
CL
(mm
)
CL
W
20 30 40 50 60
10
20
30
40
50
60
CL
W
20 30 40 50 60
10
20
30
40
50
60
CL
W
20 30 40 50 60
10
20
30
40
50
60
CL
W
20 30 40 50 60
10
20
30
40
50
60
Size-Weight relationship
Females
10 15 20 25 30 35 40 45 50 55 60 65 70
CL
m5
0%
0.0
0.5
1.0
Males
CL (mm)
10 15 20 25 30 35 40
CLm
50%
0.0
0.5
1.0
CPUEs
1992 1994 1996 1998 2000 2002 2004
Kg/
h
4
5
6
7
8
9
10
11
12
Years
1992 1994 1996 1998 2000 2002 2004
Kg/
d20
30
40
50
60
70
80CPUEs
Effort
Years
1992 1994 1996 1998 2000 2002 2004
Hou
rs
8000
12000
16000
20000
24000
28000
Landings
Palma CPUEs
Sampling on board
GLM standardised CPUEs
CALIBRATION: TUNING FLEET
Santa Pola CPUEs
Total daily catch by vessel
GSA-5
Years
1992 1994 1996 1998 2000 2002 2004
Ton
nes
80
120
160
200
240
280
GSA-6
Years
1996 1998 2000 2002 2004
Ton
nes
100
200
300
400
500
600
700
Effort
Years
1996 1998 2000 2002 2004
Day
s
6000
6500
7000
7500
8000
8500
9000
9500
1992
CL (mm)
10 20 30 40 50 60 70
N
0
2e+5
4e+5
6e+5
8e+5
1e+6
1993
CL (mm)
10 20 30 40 50 60 70
N
0
2e+5
4e+5
6e+5
8e+5
1e+6
1994
CL (mm)
10 20 30 40 50 60 70
N0.0
2.0e+5
4.0e+5
6.0e+5
8.0e+5
1.0e+6
1.2e+6
CL (mm)
10 20 30 40 50 60 70
N
0
2e+5
4e+5
6e+5
8e+5
1e+6
CL (mm)
10 20 30 40 50 60 70
N
0
1e+5
2e+5
3e+5
4e+5
5e+5
CL (mm)
10 20 30 40 50 60 70
N
0
200
400
600
800
1000
1995
CL (mm)
10 20 30 40 50 60 70
N
0
2e+5
4e+5
6e+5
8e+5
2004
1999
CL (mm)
10 20 30 40 50 60 70
N
0
200
400
600
800
1000
2000
CL (mm)
10 20 30 40 50 60 70
N
0
200
400
600
800
1000
1200
1400
2001
CL (mm)
10 20 30 40 50 60 70
N
0
200
400
600
800
1000
2002
CL (mm)
10 20 30 40 50 60 70
N
0
200
400
600
800
2003
CL (mm)
10 20 30 40 50 60 70
N
0
100
200
300
400
500
2004
CL (mm)
10 20 30 40 50 60 70
N
0
200
400
600
800
1000
1200
1996 1997
1998
GSA-5
Size distribution
1992
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
10000
12000
14000
1993
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
14000
1994
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
1996
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
10000
1997
0 1 2 3 4 5 6 70
1000
2000
3000
4000
5000
6000
7000
1999
0 1 2 3 4 5 6 70
2000
4000
6000
8000
1998
0 1 2 3 4 5 6 7
N/1
00
0
0
1000
2000
3000
4000
5000
6000
7000
2001
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
1995
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
10000
2000
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
2002
Ages
0 1 2 3 4 5 6 70
1000
2000
3000
4000
5000
6000
2003
0 1 2 3 4 5 6 70
1000
2000
3000
4000
2004
Ages
0 1 2 3 4 5 6 7
N/1
00
0
0
1000
2000
3000
4000
5000
6000
7000
Ages
1996
0 1 2 3 4 5 6 7
N/1
000
0
20004000
60008000
1000012000140001600018000
1997
0 1 2 3 4 5 6 70
2000400060008000
1000012000140001600018000
1998
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
2000
0 1 2 3 4 5 6 7
N/1
000
0
5000
10000
15000
20000
25000
2001
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
14000
2002
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
2003
Ages
0 1 2 3 4 5 6 7
N/1
000
0
5000
10000
15000
20000
25000
2004
Ages
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
1999
0 1 2 3 4 5 6 7
N/1
000
0
2000
4000
6000
8000
10000
12000
Ages
GSA-6
CL (mm)
10 20 30 40 50 60 70
0
500
1000
1500
2000
2500
3000
CL (mm)
10 20 30 40 50 60 70
N
0
10000
20000
30000
40000
50000
60000
70000
CL (mm)
10 20 30 40 50 60 70
N
0
500
1000
1500
2000
2500
2004
1999
CL (mm)
10 20 30 40 50 60 70
N
0
10000
20000
30000
40000
50000
60000
2000
CL (mm)
10 20 30 40 50 60 70
N
0
500
1000
1500
2000
2500
2001
CL (mm)
10 20 30 40 50 60 70
N
0
10000
20000
30000
40000
50000
2002
CL (mm)
10 20 30 40 50 60 70
N
0
500
1000
1500
2000
2500
3000
2003
CL (mm)
10 20 30 40 50 60 70
N
0
10000
20000
30000
40000
50000
60000
70000
2004
CL (mm)
10 20 30 40 50 60 70
N
0
1000
2000
3000
4000
1996 19971998
By sex
1992
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
10000
12000
14000
1993
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
14000
1994
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
1996
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
10000
1997
0 1 2 3 4 5 6 70
1000
2000
3000
4000
5000
6000
7000
1999
0 1 2 3 4 5 6 70
2000
4000
6000
8000
1998
0 1 2 3 4 5 6 7
N/1
00
0
0
1000
2000
3000
4000
5000
6000
7000
2001
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
1995
0 1 2 3 4 5 6 7
N/1
00
0
0
2000
4000
6000
8000
10000
2000
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
2002
Ages
0 1 2 3 4 5 6 70
1000
2000
3000
4000
5000
6000
2003
0 1 2 3 4 5 6 70
1000
2000
3000
4000
2004
Ages
0 1 2 3 4 5 6 7
N/1
00
0
0
1000
2000
3000
4000
5000
6000
7000
Ages
1996
0 1 2 3 4 5 6 7
N/1
000
0
20004000
60008000
1000012000140001600018000
1997
0 1 2 3 4 5 6 70
2000400060008000
1000012000140001600018000
1998
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
2000
0 1 2 3 4 5 6 7
N/1
000
0
5000
10000
15000
20000
25000
2001
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
14000
2002
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
12000
2003
Ages
0 1 2 3 4 5 6 7
N/1
000
0
5000
10000
15000
20000
25000
2004
Ages
0 1 2 3 4 5 6 70
2000
4000
6000
8000
10000
1999
0 1 2 3 4 5 6 7
N/1
000
0
2000
4000
6000
8000
10000
12000
Ages
Combined sex
Catch at age
Slicing Summed
By sexCatch at age
Weight at age
012345678
1991 1993 1995 1997 1999 2001 2003 2005
Years
Ag
es
Weight at age Combined sex
xcombinedse
sex
N
N*wt
Natural mortality and Age at first maturity
Age M Am50
1 0.517 0.5
2 0.517 1
3 0.517 1
4 0.517 1
5 0.517 1
6 0.517 1
gp+ 0.5 1
Combined sex
Separable VPALowestoft Stock Assessment suite program (Darby and Flatman, 1994).Separable VPA GSA-6 Year range First year
1996 Last year 2004
Age range 1-6 6+ Ft Ft=1 St St =1.2 Initial SSQ 122.671 Final SSQ 5.576 52 iterations
Separable VPA GSA-5 Year range First year
1992 Last year 2004
Age range 1-7 6+ Ft Ft=1 St St =1 Initial SSQ 81.417 Final SSQ 6.474 52 iterations
Log catch residuals
GSA-5
-0.60-0.64-0.69 -0.70-0.80-0.27-0.92-0.04 0.13 -0.01 0.10 -0.17
-0.42-0.33 0.10 -0.06 0.32 0.20 0.19 0.32 0.12 -0.10-0.06-0.28
0.28 0.42 0.33 0.24 0.31 0.04 0.15 -0.01-0.02 0.05 0.05 -0.07
0.64 0.19 -0.23 0.25 -0.44-0.13 0.31 -0.45-0.30 0.04 -0.13 0.83
0
1
2
3
4
5
1991 1993 1995 1997 1999 2001 2003
Years
Res
idu
als
log
cat
ch r
atio
GSA-6
-0.06 0.60 -0.66 0.32 0.30 -0.35 -1.37 1.10 -0.53
0.01 0.23 -0.19 -0.02 0.22 0.18 -0.39 0.02 -0.03
-0.14 -0.16 -0.23 -0.12 0.12 -0.07 0.18 -0.11 0.05
0.17 -0.17 0.28 0.03 -0.19 -0.16 0.42 -0.09 0.10
0.06 0.00 0.51 0.11 -0.34 0.19 0.12 -0.08 0.69
0
1
2
3
4
5
6
7
1995 1997 1999 2001 2003 2005
Years
Res
idu
als
Lo
g c
atch
rat
io
1992
F a
t age
0.00.20.40.60.81.01.21.4
1993 1994
1995
F a
t age
0.00.20.40.60.81.01.21.4
1996 1997
1998
F a
t age
0.00.20.40.60.81.01.21.4
1999 2000
2001
F a
t age
0.00.20.40.60.81.01.21.4
2002
Age
1 2 3 4 5 gp+
2003
Age
1 2 3 4 5 gp+
2004
Age
1 2 3 4 5 gp+
F a
t age
0.00.20.40.60.81.01.21.4
Table 8 Fishing mortality (F) at age YEAR 1992 1993 1994 1995 1996 1997 1998
AGE1 0.0621 0.0719 0.0729 0.0824 0.068 0.1067 0.05212 0.6627 0.7415 1.0144 0.9649 1.165 0.9773 0.77223 1.0563 1.1084 1.2522 1.0636 1.1533 1.0609 0.72594 1.0544 0.866 0.7881 1.0111 0.7137 0.7995 0.86175 0.7856 0.6269 0.7587 0.928 0.7736 1.0001 0.7143
+gp 0.7856 0.6269 0.7587 0.928 0.7736 1.0001 0.7143 FBAR 1- 5 0.7242 0.6829 0.7773 0.81 0.7747 0.7889 0.6252 YEAR 1999 2000 2001 2002 2003 2004 FBAR **-**
AGE1 0.0696 0.0945 0.069 0.0585 0.0453 0.074 0.05922 0.5815 0.5897 0.525 0.3919 0.29 0.5207 0.40083 0.4476 0.5703 0.5307 0.5575 0.3648 0.5799 0.50074 0.3421 0.4649 0.49 0.3832 0.4488 0.5166 0.44955 0.4515 0.6178 0.5786 0.3968 0.3607 0.2714 0.343
+gp 0.4515 0.6178 0.5786 0.3968 0.3607 0.2714 FBAR 1- 5 0.3785 0.4675 0.4387 0.3576 0.3019 0.3925
GSA-5
Separable VPA Fishing mortality by age and year
YEAR 1996 1997 1998 1999 2000 2001 2002 2003 2004 FBAR **-**
AGE1 0.0053 0.0089 0.0038 0.0097 0.0056 0.0011 0.0005 0.0384 0.0073 0.01542 0.2939 0.2807 0.1666 0.2455 0.323 0.2469 0.2238 0.5244 0.3782 0.37553 0.3056 0.3614 0.2578 0.2647 0.3369 0.3073 0.4808 0.5982 0.7191 0.59944 0.3338 0.2907 0.3787 0.2857 0.2815 0.2277 0.4334 0.4518 0.7145 0.53325 0.3277 0.3048 0.3364 0.2925 0.3123 0.2931 0.3688 0.3755 0.5495 0.4313
+gp 0.3277 0.3048 0.3364 0.2925 0.3123 0.2931 0.3688 0.3755 0.54950 FBAR 1- 5 0.2532 0.2493 0.2287 0.2196 0.2519 0.2152 0.3015 0.3977 0.4737
1996
F a
t age
0.0
0.2
0.4
0.6
0.81997 1998
1999
F a
t age
0.0
0.2
0.4
0.6
0.82000 2001
2003
Age
1 2 3 4 5 gp+
2003
Age
1 2 3 4 5 gp+
2002
Age
1 2 3 4 5 gp+
F a
t age
0.0
0.2
0.4
0.6
0.8
GSA-6
1992
F a
t age
0.00.20.40.60.81.0
1993 1994
1995
F a
t age
0.00.20.40.60.81.0
1996 1997
1998
F a
t age
0.00.20.40.60.81.0
1999 2000
2001
F a
t age
0.00.20.40.60.81.0
2002
Age
1 2 3 4 5 gp+
2003
Age
1 2 3 4 5 gp+
2004
Age
1 2 3 4 5 gp+
F a
t age
0.00.20.40.60.81.0
Fishing mortality (F) at age YEAR 1992 1993 1994 1995 1996 1997 1998
AGE1 0.05 0.0559 0.0535 0.0526 0.0322 0.0759 0.05012 0.5603 0.5643 0.7155 0.6296 0.6027 0.3589 0.48963 0.8309 0.7875 0.6987 0.4945 0.4655 0.2799 0.14284 0.7793 0.506 0.3823 0.2945 0.1859 0.1606 0.10315 0.5047 0.3408 0.2919 0.2694 0.1103 0.134 0.0751
+gp 0.5047 0.3408 0.2919 0.2694 0.1103 0.134 0.0751FBAR 1- 5 0.545 0.4509 0.4284 0.3481 0.2793 0.2019 0.1721 YEAR 1999 2000 2001 2002 2003 2004 FBAR **-**
AGE1 0.0752 0.1035 0.0746 0.0631 0.0359 0.0235 0.04082 0.5673 0.6804 0.6121 0.44 0.3214 0.3957 0.38573 0.2146 0.5456 0.6897 0.741 0.4335 0.6971 0.62384 0.0419 0.1717 0.4532 0.5955 0.7541 0.694 0.68125 0.0288 0.0501 0.1504 0.3507 0.7495 0.6327 0.5776
+gp 0.0288 0.0501 0.1504 0.3507 0.7495 0.6327 0.1855 0.3103 0.396 0.438 0.4589 0.4886
GSA-5
Fishing mortality (F) at age YEAR 1996 1997 1998 1999 2000 2001 2002 2003 2004 FBAR **-**
AGE1 0.0112 0.0252 0.0111 0.0355 0.0309 0.007 0.0035 0.0486 0.0124 0.02152 0.1152 0.1809 0.1491 0.1817 0.2636 0.188 0.1097 0.1916 0.2101 0.17053 0.1267 0.2439 0.2138 0.1989 0.2473 0.2429 0.2478 0.2868 0.2656 0.26674 0.1422 0.2134 0.3151 0.2109 0.202 0.1639 0.2959 0.2682 0.3308 0.29835 0.156 0.1928 0.3016 0.2191 0.206 0.2016 0.2254 0.2926 0.3489 0.289
+gp 0.156 0.1928 0.3016 0.2191 0.206 0.2016 0.2254 0.2926 0.34890 FBAR 1- 5 0.1103 0.1712 0.1981 0.1692 0.19 0.1607 0.1765 0.2176 0.2335
GSA-6
1996
F a
t age
0.0
0.1
0.2
0.3
0.41997 1998
1999
F a
t age
0.0
0.1
0.2
0.3
0.42000 2001
2003
Age
1 2 3 4 5 gp+
2003
Age
1 2 3 4 5 gp+
2002
Age
1 2 3 4 5 gp+
F a
t age
0.0
0.1
0.2
0.3
0.4
XSA Lowestoft Stock Assessment suite program (Darby and Flatman, 1994).
GSA-5-Recruitment (Age 1)
10000
2000030000
4000050000
60000
1992 1994 1996 1998 2000 2002 2004
Years
Rec
ruit
s (N
x100
0)
comb MF XSAM+F XSAcomb MF VPA
GSA-6-Recruitment (Age 1)
050000
100000150000200000250000
1992 1993 1994 1995 1996 1997 1998 1999 2000
Years
GSA-5-Fbar 1-5
0
0.2
0.40.6
0.8
1
1992 1994 1996 1998 2000 2002 2004
Years
Fb
ar (
1-5)
GSA-5-Total Stock Biomass
200400600800
10001200
1992 1994 1996 1998 2000 2002 2004
Years
Ton
nes
GSA-6-Total Stock Biomass
100020003000400050006000
1996 1997 1998 1999 2000 2001 2002 2003 2004
Years
GSA-6-Fbar 1-5
00.10.20.30.40.5
1996 1998 2000 2002 2004
Years
0
0.001
0.002
0.003
0.004
0.005
0.006
0.007
0.008
0 0.08 0.15 0.22 0.3 0.37 0.45 0.52 0.6 0.67 0.75
Fbar
Y/R
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
SS
B/R
Y/R
SSB/R
Y/R analysis from the XSA combined sex output
GSA-5
GSA-6
0
0.001
0.002
0.003
0.004
0.005
0.006
0.007
0 0.09 0.17 0.26 0.34 0.43 0.52 0.6 0.69 0.77 0.86
Fbar
Y/R
0
0.01
0.02
0.03
0.04
0.05
0.06S
SB
/R
Y/R
SSB/R
Reference pointsF multiplier Absolute F Y/R SSB/RFbar(1-5) 1 0.545 4.7 16.4FMax 2.2837 1.2447F0.1 0.6901 0.3761 4.4 19.1F35%SPR 1.2365 0.674 4.8 17.6
Reference pointF multiplier Absolute F Y/R SSB/RFbar(1-5) 1 0.4297 4.2 41.4FMax 1.7473 0.7507 6.1 25.9F0.1 0.7746 0.3328 5.5 34.1F35%SPR 2.7466 1.1801
Surveys: GSA-5 (BALAR)
2 3 4
39
39.5
40
00-56-1011-20
21-40
41-80
81-160
>161
kg/km2 BALAR0401
2 3 4
39
39.5
40
00-56-1011-20
21-40
41-80
81-160
>161
kg/km2 BALAR0502
2 3 4
39
39.5
40
00-56-1011-20
21-40
41-80
81-160
>161
kg/km2 BALAR0603
2 3 4
39
39.5
40
00-56-1011-20
21-40
41-80
81-160
>161
kg/km2 BALAR0404
CONCLUSIONS
CONCLUSIONS
• The overall performance of the sex combined assessment fits the data well and seems reasonable with the sum of separate estimates of males and females XSA method.
CONCLUSIONS
• The overall performance of the sex combined assessment fits the data well and seems reasonable with the sum of separate estimates of males and females XSA method.
• Separable VPA and XSA give similar results.
CONCLUSIONS
• The overall performance of the sex combined assessment fits the data well and seems reasonable with the sum of separate estimates of males and females XSA method.
• Separable VPA and XSA give similar results.
• Combined sex results are more easily understandable assessment in order to apply management measures and give an improved perception of the status of the stock as a whole.
CONCLUSIONS
• The overall performance of the sex combined assessment fits the data well and seems reasonable with the sum of separate estimates of males and females XSA method.
• Separable VPA and XSA give similar results.
• Combined sex results are more easily understandable assessment in order to apply management measures and give an improved perception of the status of the stock as a whole.
• From the surveys abundance and yield fluctuated between years and it seems quite stable.
RECOMMENDATIONS
RECOMMENDATIONS
• To not increase the fishing effort.
RECOMMENDATIONS
• To not increase the fishing effort.
• increasing the mesh size or changing to square mesh could contribute to increase the current Y/R
• Conserve the spawning capacity of the stock to reproduce, favouring mating and spawning process with temporal or spatial closed fishing seasons, zones or effort reduction during these processes.
