ICES 2004 Working Paper # 12

Transcription

ICES 2004 Working Paper # 12
ICES 2004
North-Western Working Group
Working Paper # 12
Groundfish Survey Results
for
Cod off Greenland (offshore component)
1982-2003
Hans-Joachim Rätz
Federal Research Centre for Fisheries, Institute for Sea Fisheries
Palmaille 9, D-22767 Hamburg, Germany
[email protected]
Abstract
The stock abundance and biomass increased from 23 million individuals and 45 000 tons in
1984 to 828 million individuals and 690 000 tons in 1987 due to the recruitment of the
predominating year classes 1984 and 1985. Since 1988, stock abundance and biomass
decreased dramatically by 99 % to 5 million individuals and 6 000 tons in 1993. However, the
2003 estimates confirmed the severely depleted status of the stock, although they represent the
highest stock size since 13 years and thus a significant recovery signal. The total abundance
and biomass indices amounted to 25 million individuals and 53 000 tons, respectively.
80 % of the stock in number was distributed off East Greenland with a more diverse age
structure than off West Greenland. The recruiting year classes 2000-2002 are considered weak
as compared to the strong 1984 and 1985 year classes. However, the 2002 year class
constitutes the third strongest age group 1 of the time series since 1982. Age groups 4 to 6
(year classes 1997-1999) are well presented in 2003 as compared with the mid 1990s. The
high O-group index of the 2003 year class has no predictive weight as the O-group abundance
is unrepresentative of year class strength at age 3 due to gear specifications while the age
group 1 seems to be quantitatively estimated and to represent a reasonable recruitment index.
Since 1997, the cod did mature at significantly lower ages, probably as a reaction to the
continued favourable water temperature in the near bottom layers. The weighted mean length
and weight of the age groups 3-6 revealed pronounced area and temperature effects. Driven by
the high abundance of cod off West Greenland, the mean sizes of the age groups 1-6 were low
in 1987-91. The mean length and weight of age groups 3-6 increased significantly from low
levels since 1991 as a consequence of their increased occurrence off East Greenland and
higher temperatures.
1
Introduction
This paper presents estimates of cod stock abundance and biomass indices disaggregated by age groups as
derived from annual groundfish surveys commenced in 1982, the only regular source of quantitative information
from the traditional fishing grounds off West and East Greenland south of 67° northern latitude. Size at age is
given in terms of length and weight. Changes in size at age are analysed for area and temperature effects.
Materials and Methods
Abundance, biomass estimates and length structures were derived from annual groundfish surveys covering shelf
areas and the continental slope off West and East Greenland. Surveys commenced in 1982 and were primarily
designed for the assessment of cod. Because of favourable weather and ice conditions and to avoid spawning
concentrations, autumn was chosen for the time of the surveys. These were carried out by the research vessel
(R/V) WALTHER HERWIG (II) throughout most of the time period. In 1984 R/V ANTON DOHRN was used
and she was replaced by the new R/V WALTHER HERWIG III since 1994, respectively.
The fishing gear used was a standardized 140-feet bottom trawl, its net frame rigged with heavy ground gear
because of the rough nature of the fishing grounds. A small mesh liner (10mm) was used inside the cod end. The
horizontal distance between wing-ends was 25 m at 300 m depth, the vertical net opening being 4 m. In 1994,
smaller Polyvalent doors (4.5 m2, 1,500 kg) were used for the first time to reduce net damages due to overspread
caused by bigger doors (6 m2, 1,700 kg), which have been used earlier. All calculations of abundance and
biomass indices were based on the 'swept area' method using 22 m horizontal net opening as trawl parameter, i. e.
the constructional width specified by the manufacturer. The towing time was normally 30 min. at a speed of 4.5
knots. Trawl parameters are listed in Table 1. Hauls, which received net damage or became hang-up after less
than 15 minutes, were rejected. Some hauls of the 1987 and 1988 surveys were also included although their
towing time had been intentionally reduced to 10 minutes because of the expected large cod catches as observed
from echo sounder traces.
Fish were identified to species or lowest taxonomic level and the catch in number and weight was recorded. Total
fish lengths were measured to cm below. Weight (g) at age calculations were based on the regression
f(x)=0.00895x3.00589, x=length (cm), which was determined on the basis of 3 482 individual measurements.
The surveys were primarily designed for the assessment of cod. In order to reduce the error of abundance
estimates, the subdivision of shelf areas and the continental slope into different geographic and depth strata was
required due to a pronounced heterogeneity of cod distribution. The survey area was thus split into seven
geographic strata. Each stratum was itself subdivided into two depth strata covering the 0-200 m and 201-400 m
zones. Figure 1 and Table 2 indicate the names of the 14 strata, their geographic boundaries, depth ranges and
areas in nautical square miles (nm2). All strata were limited at the 3 mile offshore line.
The applied strategy was to distribute the sampling effort according both to the stratum areas and to cod
abundance. Consequently, fifty percent of the hauls were allocated proportionally to strata by stratum area while
the other fifty percent were apportioned on the basis of a review of the historical mean cod abundance/nm 2, all
hauls being randomly distributed within trawlable areas of the various strata. Non-trawlable areas were mainly
located inshore. During 1982-2003, 3 000 successful sets were carried out, the numbers of valid sets by year and
stratum being listed in Table 3. Apart from stratum 7.2 (Dohrn Bank), East Greenland strata were not covered
adequately in 1984, 1992 and 1994 due to technical problems. In 1995 and 2002, the survey area off West
Greenland was incompletely covered due to technical problems. Only 50 % of the strata of West Greenland were
covered. Stratum 7.1 has a very low area and therefore never been covered. Since 1996, the entire survey area
was considered to be almost completely covered. Figure 1 shows the positions of hauls conducted during the
most recent survey.
Stratified abundance estimates were calculated from catch-per-tow data using the stratum areas as weighting
factor (Cochran, 1953; Saville, 1977). Strata with less than five valid sets were rejected from the calculation. The
coefficient of catchability was set arbitrarily at 1.0, implying that estimates are merely indices of abundance and
biomass. Respective confidence intervals (CI) were set at the 95% level of significance of the stratified mean.
Age determinations were based on length-stratified otolith (sagitta) collections and conducted using transmitted
light. Until 1992, otoliths were cut into 2 halves and annuli were counted under a binocular microscope. Since
1993, thin sections were cut from the central region of the otolith after embedding in black polyester resin.
2
Comparative age readings revealed no significant differences between both methods. Calculations of age
structures, compositions and growth were based on data pooled to 3 cm length groups. In 2003, 1 203 individual
age determinations were conducted.
Maturity at age was determined from visual observations. However, the results should be interpreted carefully
since the surveys were conducted in autumn when the gonads of mature fish were in resting stages. During this
season, it was often difficult to distinguish immature from mature cod.
As a standard procedure, near bottom temperatures were measured directly before or after trawling in the vicinity
of the swept area by a CTD-sonde with a precision of a hundredth °C. Mean weighted temperature in the near
bottom layer was calculated using the stratum areas as weighting factor. The values are given in Table 3.
Results
Tables 4 and 5 list abundance and biomass indices by stratum, West and East Greenland and total in 1982-2003.
Indices varied significantly between strata and years. Trends of the abundance and biomass estimates for West
and East Greenland are shown in Figures 2 and 3, respectively. These Figures illustrate the pronounced increase
in stock abundance and biomass from 23 million individuals and 45 000 tons in 1984 to 828 million individuals
and 690 000 tons in 1987. This trend was caused by the recruitment of the predominating year classes 1984 and
1985, which were mainly distributed in the northern and shallow strata 1.1, 2.1 and 3.1 off West Greenland
during 1987-89. Such high indices were never observed in strata off East Greenland, although their abundance
and biomass estimates increased during the period 1989-91 pointing to eastbound migration. During the period
1987-89, the high abundance estimates were accompanied with high confidence intervals. The low precisions
were due to enormous variation in catch per tow data. Since 1988, stock abundance and biomass decreased
dramatically by 99 % to 5 million individuals and 6 000 tons in 1993. However, the 2003 estimates confirmed the
severely depleted status of the stock with regard to the historic level, although they represent the highest stock
size in biomass since 13 years. The total abundance and biomass indices amounted to 26 million individuals and
53 000 tons, respectively.
Age disaggregated abundance indices for West, East Greenland and total are listed in Tables 6, 7 and 8,
respectively. The very strong year classes 1984 and 1985 dominated the stock during 1985-1991. In 2002, the
stock structure off West Greenland was found to be composed almost exclusively of the recruiting age groups 2
and 3 (98 %). 80 % of the stock in number was distributed off East Greenland with a more diverse age structure.
The recruiting year classes 2000-2002 are considered weak as compared to the strong 1984 and 1985 year
classes. However, the 2002 year class constitutes the third strongest age group 1 of the time series since 1982.
Age groups 4 to 6 (year classes 1997-1999) are well presented in 2003 as compared with the mid 1990s. The
high O-group index of the 2003 year class has no predictive weight as the O-group abundance is unrepresentative
of year class strength at age 3 due to gear specifications while the age group 1 seems to be quantitatively
estimated and to represent a reasonable recruitment index (Fig. 4).
The proportion mature at age and resulting estimates of spawning stock sizes in numbers and weight are given in
Tables 9, 10 and 11, respectively. The calculation of the spawning stock biomass indices were based on the
weighted mean weight by age and years as listed in Tables 15-17. In the past six years, the cod did mature at
significantly lower ages, probably as a reaction to the continued favourable water temperature in the near bottom
layers (Rätz, 1999). In 2003, the age groups 2, 3 and 4 were recorded to be among the highest proportion mature
in the entire time series. The indices of spawning stock sizes are illustrated in Figures 2 and 3 as solid lines. Both
estimates peaked in 1989 when the strong year class 1984 became mature. Since 1992, the spawning stock was
practically absent but displays a significant recovery signal most recently (since 2001).
The weighted mean length and weight of the age groups 1-10 years for West, East Greenland and total are listed
in Tables 12-17, respectively. Trends of these values are illustrated in Figures 5 and 6 for the period 1982-2003.
They reveal pronounced area and temperature effects as demonstrated by multiple linear regression models (Fig.
7 and Tab. 18). 43, 56, 60, and 39 % of the observed variation in length at ages 3-6 are explained by the positive
influence of the near bottom temperature and the ratio of fish distributed off East Greenland, respectively. The
majority of recorded sizes at ages 2 to 10 years off East Greenland were found to be bigger than those off West
Greenland. Driven by the high abundance of small growing cod off West Greenland, the mean sizes of the age
groups 1-6 were low in 1987-91. Thereafter, mean length and weight of age groups 3-6 increased significantly
from low levels as a consequence of their increased occurrence off East Greenland and higher temperatures.
3
References
Anon., 1984. Report of the Working Group on Cod Stocks off East Greenland. ICES C.M., A:5:1-25
Cochran, W. G. 1953. Sampling techniques. John Wiley & Sons Inc., New York: 1-330
Rätz, H.-J. 1999. Structures and Changes of the Demersal Fish Assemblage off Greenland, 1982-96. NAFO Sci.
Coun. Studies, 32: 1-15
Saville, A. 1977. Survey methods of apprising fishery resources. FAO Fish. Tech. Pap. 171: 1-76
4
Table 1 Trawl parameters of the survey.
Gear
Horizontal net opening
Standard trawling speed
Towing time
Coefficient of catchability
140-feet bottom trawl
22 m
4.5 kn
30 minutes
1.0
Table 2 Specification of strata.
Stratum
1.1
1.2
2.1
2.2
3.1
3.2
4.1
4.2
5.1
5.2
6.1
6.2
7.1
7.2
Sum
south
geographic boundaries
north
east
west
64°15'N
64°15'N
62°30'N
62°30'N
60°45'N
60°45'N
59°00'N
59°00'N
59°00'N
59°00'N
63°00'N
63°00'N
64°45'N
64°45'N
67°00'N
67°00'N
64°15'N
64°15'N
62°30'N
62°30'N
60°45'N
60°45'N
63°00'N
63°00'N
66°00'N
66°00'N
67°00'N
67°00'N
57°00'W
57°00'W
55°00'W
55°00'W
53°00'W
53°00'W
50°00'W
50°00'W
44°00'W
44°00'W
41°00'W
41°00'W
35°00'W
35°00'W
50°00'W
50°00'W
50°00'W
50°00'W
48°00'W
48°00'W
44°00'W
44°00'W
40°00'W
40°00'W
35°00'W
35°00'W
29°00'W
29°00'W
depth
(m)
area
(nm2)
1-200
201-400
1-200
201-400
1-200
201-400
1-200
201-400
1-200
201-400
1-200
201-400
1-200
201-400
6805
1881
2350
1018
1938
742
2568
971
2468
3126
1120
7795
92
4589
37463
Table 3 Numbers of valid hauls by stratum and total and weighted (by stratum area) mean near
bottom temperature, 1982-2003.
YEAR
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
1.1
20
26
25
10
27
25
34
26
19
19
6
9
16
0
5
5
9
8
13
0
0
0
1.2
11
11
13
8
9
11
21
14
7
11
6
6
13
0
5
6
5
6
6
0
0
0
2.1
16
25
26
26
21
21
28
30
23
23
6
9
13
3
8
5
10
14
14
15
7
7
2.2
7
11
8
10
9
4
5
9
8
7
5
6
8
0
5
5
7
8
7
7
2
6
3.1
9
17
18
17
16
18
18
8
16
12
6
10
10
10
12
6
11
13
14
15
5
7
3.2
6
5
6
5
7
3
5
3
3
6
6
8
6
7
5
5
6
6
5
5
6
7
4.1
13
18
21
21
18
21
18
25
21
14
7
7
7
10
10
8
10
9
9
11
8
6
4.2
2
4
4
4
3
3
2
3
6
5
5
0
5
5
5
5
5
3
5
6
4
5
5.1
1
3
5
5
3
19
21
17
18
8
0
9
0
8
7
5
5
5
6
5
6
6
5
5.2
10
19
4
21
15
16
8
18
19
11
0
6
0
6
9
5
8
6
5
6
6
5
6.1
3
10
2
14
14
13
13
12
6
10
0
6
0
6
5
4
6
6
8
9
5
5
6.2
12
36
8
50
37
40
39
29
15
28
0
18
0
17
13
8
12
13
16
18
10
7
7.1
1
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
7.2
25
18
5
28
34
18
26
11
13
16
6
14
6
12
9
8
9
5
11
15
10
16
Sum
136
203
145
219
214
212
238
205
174
170
53
108
84
84
98
75
103
102
119
112
69
77
Temp. (°C)
3.139
3.012
2.698
4.181
4.136
3.783
3.959
3.295
3.461
3.558
3.489
3.597
3.620
3.862
4.709
4.189
5.181
4.435
3.860
5.128
4.904
5.500
Table 4 G. morhua. Abundance indices (1000) for West, East Greenland and total by stratum, 1982-2003. Confidence intervals (CI) are given in per cent of the statified mean at 95% level of
significance. () incorrect due to incomplete sampling.
YEAR
1.1
1982
5092
1983
431
(1984)
377
1985
19630
1986
32438
1987 330944
1988
92024
1989
2497
1990
965
1991
268
(1992)
552
1993
566
(1994)
206
1995
1996
152
1997
0
1998
1524
1999
191
2000
374
2001
2002
2003
1.2
2.1
729
47957
467
16013
179
4714
2428
13222
1236
50908
1651 248002
2423 338740
920
27930
513
4155
205
180
622
117
457
176
103
33
126
47
0
70
457
76
35
45
56
101
1072
439
1081
2.2
1888
5170
171
4395
229
84935
673
362
152
137
127
33
38
0
49
19
283
65
171
3.1
15114
14881
5201
10531
37446
154681
47336
261502
6014
1027
121
80
72
138
121
120
14
380
545
6415
638
3014
3.2
3706
2326
689
1638
1321
89
611
74
31
23
67
0
5
0
14
16
16
42
135
4.1
17790
10916
5353
7499
22104
51114
60946
65203
10303
1839
151
0
82
58
298
108
77
182
128
586
3002
1217
4.2
5.1
5.2
468
2228
1274
18317
7985
30906
4956
2343
373
780
9832
8085
38407
2524
1786
3978
6950
6527
2060
11600
4533
779
6.2
6173
2276
1750
3348
6676
6081
4375
9383
9041
1958
1252
98
922
502
265
290
74
296
518
985
785
338
908
78
0
0
0
19
22
22
644
328
2933
260
3654
382
624
148
631
288
1107
959
4794
4063
3564
12213
523
269
22
15
0
0
15
21
7
15
6
6.1
405
1257
2975
1753
5020
8766
7.1
7.2
1449
2213
790
1141
828
878
1083
1436
4200
3541
658
527
801
257
515
3456
821
344
546
3937
2730
5108
WEST EAST
92276
8090
50204
7991
16684
-6603
59343
12404
145682
15234
786392
41635
626493
23588
358725
91732
34525
25254
4805
10407
2043
-658
1437
3301
574
-801
278
7187
811
1447
315
4153
1723
1671
912
2769
1926
4816
8160
7604
4121
9691
5632
19904
TOTAL CI
100366
28
58195
25
23286
32
71747
33
160915
32
828026
59
650080
48
450459
59
59777
43
15213
29
2700
50
4738
36
1375
36
7463
93
2257
38
4469
75
3394
54
3681
34
6742
36
15764
39
13812
41
25537
45
Table 5 G. morhua. Biomass indices (tons) for West, East Greenland and total by stratum, 1982-2003. Confidence intervals (CI) are given in per cent of the statified mean at 95% level of significance.
() incorrect due to incomplete sampling.
YEAR
1.1
1982
2375
1983
354
(1984)
823
1985
2531
1986
10643
1987 283592
1988
94174
1989
728
1990
225
1991
88
(1992)
136
1993
136
(1994)
27
1995
1996
20
1997
0
1998
75
1999
27
2000
102
2001
2002
2003
1.2
2.1
307
63685
205
20215
233
7508
250
12869
483
26099
545 200634
1367 333848
228
25829
113
3553
71
73
196
24
88
49
32
5
64
40
0
24
130
24
24
2
7
21
296
167
174
2.2
2632
7827
234
2351
79
77967
441
190
46
36
34
23
20
0
9
6
135
31
74
3.1
20318
22806
7217
10731
28510
116609
44593
231238
5779
1207
21
45
23
25
50
107
2
120
140
2171
252
1364
3.2
8744
9594
1054
990
1423
93
589
14
10
10
13
0
4
0
9
10
8
12
58
4.1
30426
21373
8492
5953
19483
37210
55944
75386
13187
2622
82
0
3
10
193
110
21
46
18
162
1679
562
4.2
5.1
5.2
1929
6146
3511
10316
8749
40613
9230
4235
1357
2645
9053
18206
127866
6812
5780
9956
18631
9292
6162
34957
12954
1263
6.2
14561
11342
4108
9440
16541
17617
16260
31320
24406
7468
861
59
1742
1076
94
168
57
84
64
365
365
106
459
184
0
0
0
3
31
47
531
478
1114
755
13750
1006
1193
592
1738
935
1606
2237
10679
10398
7073
11388
451
102
13
7
0
0
21
15
10
31
7
6.1
620
1630
1409
2384
9990
26461
7.1
7.2
7127
13152
5236
5745
3364
5314
3570
4786
12560
14006
1216
1859
2790
381
1675
12473
3052
482
2038
11794
6861
12790
WEST EAST
128486
23617
82375
34151
25563
19742
35674
33571
86721
41181
638590
51591
607987
52948
333850 239543
34435
65962
5148
32752
610
1216
362
5597
136
2790
55
15524
371
3603
284
13722
130
4348
240
3917
570
4778
2677
16196
2110
19726
2264
50867
TOTAL CI
152103
25
116526
25
45305
34
69245
39
127902
26
690182
63
660935
46
573393
45
100397
34
37899
36
1826
69
5959
41
2926
68
15579 155
3974
56
14007
90
4479
91
4157
62
5349
40
18873
42
21836
51
53131
73
Table 6 G. morhua, West Greenland. Age disaggregate abundance indices (1000), 1982-2003.
*) calculated proportionally using age compositions reported by the ICES Working Group on Cod
Stocks off East Greenland (Anon., 1984).
YEAR
1982
*1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
0
0
0
159
831
0
0
0
12
159
0
0
0
0
0
0
0
48
29
0
0
12
68
1
176
0
5
38016
14148
317
257
204
47
293
263
10
283
0
147
12
1642
401
165
620
13
3225
2
884
1469
38
1481
112532
45473
3332
2461
1007
224
1427
832
45
241
11
27
0
392
1015
6202
1061
392
3
33470
2815
2070
948
4089
692567
102767
3565
3005
476
220
544
199
16
638
15
0
87
615
1100
2972
1090
4
11368
26619
1531
6403
903
24230
510980
93687
1244
1397
36
20
38
22
10
263
5
7
116
159
64
743
5
32504
4960
9848
2833
6823
5929
5425
254002
21724
164
77
28
5
0
0
0
25
0
0
51
0
93
6
9528
10969
842
7682
2095
11813
613
3934
7221
1894
0
6
0
0
10
0
0
6
0
0
0
25
7
2622
1882
1873
467
4271
1637
1122
0
47
317
28
0
5
0
0
0
0
0
0
0
0
0
8
578
992
87
646
133
4006
654
535
0
6
0
0
0
0
0
0
0
0
0
0
0
0
9
939
317
186
27
616
0
1274
114
0
0
0
0
0
0
0
0
0
0
0
0
0
0
10
91
168
27
35
34
366
32
228
0
0
0
0
0
0
0
0
0
0
0
0
0
0
11+
90
13
0
0
39
30
35
0
19
0
0
0
0
0
0
0
0
0
0
0
0
0
TOTAL
92250
50204
16666
59369
145683
786368
626491
358742
34473
4771
2051
1440
575
279
816
317
1720
922
1911
8132
4122
5636
Table 7 G. morhua, East Greenland. Age disaggregate abundance indices (1000), 1982-2003.
*) calculated proportionally using age compositions reported by the ICES Working Group on Cod
Stocks off East Greenland (Anon., 1984). () incomplete sampling.
YEAR
1982
*1983
(1984)
1985
1986
1987
1988
1989
1990
1991
(1992)
1993
(1994)
1995
1996
1997
1998
1999
2000
2001
2002
2003
0
0
0
0
230
0
0
11
0
0
0
15
0
0
0
0
0
63
191
0
0
96
1102
1
0
0
18
1932
1397
13
25
7
38
106
44
17
87
7
0
0
240
632
808
309
8
585
2
239
411
74
556
3351
13785
163
179
80
377
77
44
0
2523
0
37
192
665
1074
944
415
141
3
841
605
1342
118
1693
17788
6982
489
551
394
74
1857
29
1125
502
28
21
417
1341
1468
1824
1067
4
1764
1008
657
2494
551
3890
11094
17396
462
685
69
370
261
370
258
1508
45
138
787
2244
2026
4530
5
1999
1187
1397
2034
2417
1027
2016
63216
5128
147
54
279
143
1730
295
1611
462
302
157
1349
2080
4285
8
6
1227
2125
855
1852
1120
1770
480
3021
18012
3512
47
278
87
450
255
566
435
179
291
705
1952
4486
7
379
1287
1617
785
2191
457
1435
294
265
5035
143
88
145
141
60
236
156
200
75
211
889
2374
8
130
302
407
2000
566
1571
152
4870
72
81
52
272
0
460
77
140
43
0
141
191
235
1074
9
1392
265
103
295
1627
187
674
406
251
37
0
95
29
36
0
0
0
35
115
73
83
188
10
73
703
36
56
116
1093
98
1795
0
11
0
0
0
217
0
0
0
24
31
36
36
0
11+
72
101
95
36
139
36
469
42
349
9
6
0
0
125
0
19
0
0
0
9
30
25
TOTAL
8116
7994
6601
12388
15168
41617
23599
91715
25208
10394
581
3300
781
7184
1447
4145
1657
2783
4820
7539
9674
19857
Table 8 G. morhua, Greenland (total). Age disaggregate abundance indices (1000), 1982-2003.
*) calculated proportionally using age compositions reported by the ICES Working Group on Cod
Stocks off East Greenland (Anon., 1984). () incomplete sampling.
YEAR
1982
*1983
(1984)
1985
1986
1987
1988
1989
1990
1991
(1992)
1993
(1994)
1995
1996
1997
1998
1999
2000
2001
2002
2003
0
0
0
159
1061
0
0
11
12
159
0
15
0
0
0
0
0
111
220
0
0
108
1170
1
176
0
23
39948
15545
330
282
211
85
399
307
27
370
7
147
12
1882
1033
973
929
21
3810
2
1123
1880
112
2037
115883
59258
3495
2640
1087
601
1504
876
45
2764
11
64
192
1057
2089
7146
1476
533
3
34311
3420
3412
1066
5782
710355
109749
4054
3556
870
294
2401
228
1141
1140
43
21
504
1956
2568
4796
2157
4
13132
27627
2188
8897
1454
28120
522074
111083
1706
2082
105
390
299
392
268
1771
50
145
903
2403
2090
5273
5
34503
6147
11245
4867
9240
6956
7441
317218
26852
311
131
307
148
1730
295
1611
487
302
157
1400
2080
4378
6
10755
13094
1697
9534
3215
13583
1093
6955
25233
5406
47
284
87
450
265
566
435
185
291
705
1952
4511
7
3001
3169
3490
1252
6462
2094
2557
294
312
5352
171
88
150
141
60
236
156
200
75
211
889
2374
8
708
1294
494
2646
699
5577
806
5405
72
87
52
272
0
460
77
140
43
0
141
191
235
1074
9
2331
582
289
322
2243
187
1948
520
251
37
0
95
29
36
0
0
0
35
115
73
83
188
10
164
871
63
91
150
1459
130
2023
0
11
0
0
0
217
0
0
0
24
31
36
36
0
11+
162
1140
95
36
178
66
504
42
368
9
6
0
0
125
0
19
0
0
0
9
30
25
TOTAL
100366
58198
23267
71757
160851
827985
650090
450457
59681
15165
2632
4740
1356
7463
2263
4462
3377
3705
6731
15671
13796
25493
Table 9 G. morhua, Greenland (total). Proportion mature at ages 0-10 years, 1982-2003. *) No
observations available, values taken from previous years.
YEAR
1982
*1983
1984
1985
1986
*1987
1988
1989
*1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
0
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
1
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.06
0.00
0.04
2
0.00
0.00
0.15
0.01
0.00
0.00
0.00
0.00
0.00
0.00
0.04
0.05
0.00
0.00
0.00
0.00
0.00
0.02
0.28
0.22
0.31
0.49
3
0.02
0.02
0.12
0.02
0.00
0.00
0.02
0.02
0.02
0.01
0.27
0.53
0.04
0.00
0.00
0.29
0.67
0.07
0.70
0.73
0.88
0.84
4
0.10
0.20
0.53
0.18
0.13
0.13
0.22
0.55
0.55
0.04
0.69
0.63
0.36
0.29
0.33
0.70
0.60
0.36
0.91
0.91
0.92
0.95
9
5
0.52
0.52
0.89
0.68
0.25
0.25
0.66
0.81
0.81
0.13
0.71
0.48
0.50
0.51
0.56
0.78
0.97
0.89
0.95
0.97
0.96
0.95
6
0.73
0.73
0.98
0.86
0.84
0.84
0.86
0.91
0.91
0.40
1.00
0.76
1.00
0.81
0.82
0.90
0.96
1.00
0.97
0.97
0.95
0.99
7
0.89
0.89
0.99
0.97
0.93
0.93
0.92
1.00
1.00
0.75
0.92
0.75
1.00
1.00
1.00
0.92
1.00
0.94
0.83
1.00
0.96
1.00
8
0.95
0.98
1.00
0.97
0.91
0.91
1.00
0.98
0.98
1.00
1.00
0.92
1.00
1.00
0.80
1.00
1.00
1.00
1.00
1.00
1.00
9
1.00
1.00
1.00
0.90
0.97
0.97
0.99
1.00
1.00
1.00
1.00
0.89
1.00
1.00
1.00
1.00
10
1.00
1.00
1.00
1.00
1.00
1.00
0.92
0.98
0.98
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
Table 10 G. morhua, Greenland (total). Spawning stock indices in numbers (1000), 1982-2003.
YEAR
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
56
0
152
2
0
0
17
20
0
0
0
0
0
0
60
44
0
0
0
0
0
21
585
1572
458
261
3
686
68
409
21
0
0
2195
81
71
9
79
1273
9
0
0
12
14
35
1369
1875
4220
1812
4
1313
5525
1160
1601
189
3656
114856
61096
938
83
72
246
108
114
88
1257
30
52
822
2187
1923
5009
5
17942
3196
10008
3310
2310
1739
4911
256947
21750
40
93
147
74
882
165
1257
472
269
149
1358
1997
4159
6
7851
9559
1663
8199
2701
11410
940
6329
22962
2162
47
216
87
365
217
509
418
185
282
684
1854
4466
7
2671
2820
3455
1214
6010
1947
2352
294
312
4014
157
66
150
141
60
217
156
188
62
211
853
2374
8
673
1268
494
2567
636
5075
806
5297
71
87
52
250
0
460
62
140
43
0
141
191
235
1074
9
2331
582
289
290
2176
181
1929
520
251
0
0
85
29
36
0
0
0
35
115
73
83
188
10
164
871
63
91
150
1459
120
1983
0
0
0
0
0
217
0
0
0
24
31
36
36
0
TOTAL
33793
23889
17653
17349
14350
25467
128578
332589
46355
6404
560
2327
457
2340
592
3411
1133
809
3556
8252
11689
19520
Table 11 G. morhua, Greenland (total). Spawning stock biomass indices (tons), 1982-2003.
YEAR
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
6
0
5
0
16
2
0
0
4
5
0
0
0
0
0
0
14
6
0
0
0
0
0
21
121
467
122
91
3
393
37
212
13
0
0
1034
35
25
3
36
820
5
0
0
12
15
61
604
1412
2781
1462
4
1280
5456
1219
1879
251
3364
118532
51626
677
67
88
315
213
162
165
2214
53
793
708
3890
2963
7028
5
32259
5761
14442
6887
4438
2189
7612
407003
22294
53
153
317
219
2602
407
4340
1381
685
239
3084
4579
9537
10
6
18003
22134
4113
18358
7621
26414
2653
14240
50907
4197
142
601
417
1522
779
2069
1479
924
593
1921
5445
15425
7
8408
8937
11447
4761
19327
5158
9076
1162
1029
13017
478
238
711
738
307
991
602
0
202
830
3305
10146
8
2908
5510
2314
11226
3014
17971
2648
25377
405
349
180
1208
0
2726
359
656
290
298
733
982
1093
5911
9
13909
3479
1309
1652
11932
1099
8898
2624
1727
0
0
519
167
347
0
0
0
216
723
467
541
1126
10
1110
5909
363
566
927
9389
780
12329
0
0
0
0
0
1615
0
0
0
0
253
260
253
0
TOTAL
79511
57223
36162
45630
48976
65584
155556
514773
77064
17756
1091
4024
1732
10445
2017
10416
3820
3004
4176
13381
21299
50967
Table 12 G. morhua, West Greenland. Weighted mean length (cm, by stratum abundance) at age 110 years, 1982, 1984-2003.
YEAR
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
1
16.9
2
27.5
3
39.6
4
46.5
5
57.8
6
61.8
7
68.6
8
76.3
9
82.0
10
91.3
19.5
21.9
19.9
15.9
16.1
15.8
16.1
17.6
20.2
16.5
17.0
24.6
26.4
32.9
29.0
28.5
25.9
23.2
24.8
29.3
24.4
24.0
27.3
22.5
33.2
34.6
39.6
37.9
42.4
36.8
35.9
33.2
33.9
34.6
35.4
36.8
33.0
38.2
34.5
52.9
54.4
57.0
50.7
50.0
53.5
46.3
46.6
46.8
46.5
49.5
60.1
60.3
62.3
61.7
59.7
54.0
53.4
52.9
68.0
69.8
67.2
62.5
68.6
73.2
71.4
75.1
69.1
67.0
68.0
78.7
78.3
76.8
87.6
75.9
78.8
72.8
76.5
79.2
33.4
29.5
31.4
30.6
34.0
40.6
35.4
38.5
39.5
41.9
44.5
47.5
49.6
46.6
48.1
44.3
40.3
41.4
41.8
37.8
40.5
37.5
43.5
47.7
55.5
49.5
44.3
48.8
44.0
49.5
16.6
19.5
17.7
20.4
16.2
19.1
19.5
22.3
49.5
57.5
60.8
73.6
70.6
46.5
46.5
64.5
73.5
54.9
67.5
47.0
54.6
62.6
Table 13 G. morhua, East Greenland. Weighted mean length (cm, by stratum abundance) at age 1-10
years, 1982, 1984-2003. () incomplete sampling.
YEAR
1982
1983
(1984)
1985
1986
1987
1988
1989
1990
1991
(1992)
1993
(1994)
1995
1996
1997
1998
1999
2000
2001
2002
2003
1
2
35.9
3
43.8
4
53.7
5
63.3
6
72.5
7
79.4
8
84.4
9
89.7
10
89.1
22.5
22.9
21.3
15.4
33.1
36.3
34.5
31.4
31.1
30.2
35.8
27.7
35.3
33.8
44.4
48.4
46.4
41.2
43.1
38.9
38.2
35.3
43.6
43.0
49.5
36.1
42.8
55.0
48.5
40.2
36.9
47.1
45.0
47.3
58.2
57.7
57.2
45.9
57.8
49.6
50.0
50.4
55.6
52.6
62.8
54.8
59.4
59.5
57.9
50.4
45.7
58.5
55.5
54.2
62.2
70.1
66.3
56.5
69.4
64.9
56.1
58.8
70.2
63.2
69.3
68.5
64.5
72.2
69.1
68.5
55.9
63.4
63.0
63.2
69.0
71.6
77.2
73.2
77.5
73.8
65.9
63.2
69.1
67.6
80.5
76.9
73.1
76.2
72.8
74.1
61.2
67.4
68.4
72.3
74.9
78.6
76.8
79.1
79.8
75.5
74.9
71.5
70.9
73.2
80.7
82.9
82.3
79.2
74.9
81.2
70.7
75.4
75.0
77.5
81.3
80.3
81.4
82.3
89.1
81.8
85.3
78.1
72.3
80.7
79.6
85.9
86.9
87.1
90.8
85.1
90.8
82.4
84.0
95.3
90.1
94.2
93.2
88.9
103.5
87.4
85.5
101.6
93.2
19.5
17.9
21.1
12.5
20.7
16.5
19.5
22.3
21.0
21.8
24.5
13.5
22.7
30.1
22.5
25.7
30.9
27.2
35.0
31.3
32.6
11
86.4
85.9
79.9
90.2
82.7
82.4
79.7
84.3
97.5
88.1
88.6
89.2
86.7
99.3
96.1
92.3
91.5
Table 14 G. morhua, Greenland (total). Weighted mean length (cm, by stratum abundance) at age 110 years, 1982, 1984-2003. () incomplete sampling.
YEAR
1982
1983
(1984)
1985
1986
1987
1988
1989
1990
1991
(1992)
1993
(1994)
1995
1996
1997
1998
1999
2000
2001
2002
2003
1
16.9
2
29.3
3
39.7
4
47.4
5
58.1
6
63.0
7
70.0
8
77.8
9
86.6
10
90.3
21.8
22.0
20.0
15.8
18.8
15.9
16.9
18.5
19.1
19.2
16.9
19.5
16.6
19.5
18.3
20.8
20.8
20.9
17.2
22.4
30.2
29.1
32.9
29.6
28.6
26.2
24.1
26.6
29.6
24.9
24.0
29.9
22.5
27.0
25.7
31.8
28.3
31.9
30.8
33.7
38.4
40.6
40.4
42.4
37.2
36.3
34.0
34.5
36.9
41.3
38.4
36.0
40.2
47.8
48.5
40.2
36.4
43.5
41.6
44.5
48.6
50.4
52.5
46.5
48.3
45.2
42.9
44.4
50.9
51.9
60.0
53.8
58.8
57.7
57.7
50.4
45.5
57.9
55.2
53.5
54.0
61.0
59.4
51.6
55.3
55.7
48.2
52.4
56.4
61.7
68.6
68.5
64.5
72.2
68.3
68.5
55.9
62.8
63.0
63.0
64.6
62.5
67.5
63.2
67.5
62.6
62.3
59.6
69.1
67.2
80.5
76.9
73.1
76.2
72.8
73.9
61.2
67.4
68.4
72.2
71.2
75.3
70.5
66.1
74.8
75.5
71.1
70.7
69.2
73.2
80.2
82.9
82.3
79.2
74.9
81.2
70.7
75.4
75.0
77.5
79.9
78.1
80.2
72.8
71.1
80.5
85.3
75.9
72.3
80.7
79.0
85.3
84.2
87.1
79.4
81.9
90.8
82.4
85.6
87.8
87.6
88.8
88.8
87.8
103.5
87.4
85.5
101.6
93.2
86.4
85.9
79.9
90.2
82.7
82.4
79.7
84.3
97.5
88.1
88.6
89.2
86.7
99.3
96.1
92.3
91.5
Table 15 G. morhua, West Greenland. Weighted mean weight (g., by stratum abundance) at age 1-10
years, 1982, 1984-2003.
YEAR
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
1
44
2
190
3
568
4
920
5
1770
6
2164
7
2962
8
4078
9
5065
10
6995
68
96
72
37
38
36
38
50
75
41
45
136
168
325
223
211
159
114
139
230
132
126
186
104
334
379
568
498
697
456
423
334
356
379
405
456
328
510
375
1356
1475
1697
1194
1145
1403
909
926
938
920
1111
1990
2010
2217
2154
1941
1443
1395
1356
2885
3121
2784
2239
2949
3600
3341
3889
3028
2735
2885
4476
4408
4159
6177
4014
4493
3541
4192
4562
340
234
283
262
359
612
405
522
564
673
807
981
1118
926
1019
796
599
649
668
494
608
482
753
994
1567
1111
796
1064
780
1111
42
68
50
77
39
63
68
101
920
2461
3645
1516
2822
951
68
1492
12
1111
1743
2061
2250
920
3630
3229
Table 16 G. morhua, East Greenland. Weighted mean weight (g., by stratum abundance) at age 1-10
years, 1982, 1984-2003. () Incomplete sampling.
YEAR
1982
1983
(1984)
1985
1986
1987
1988
1989
1990
1991
(1992)
1993
(1994)
1995
1996
1997
1998
1999
2000
2001
2002
2003
1
2
423
3
769
4
1419
5
2326
6
3498
7
4597
8
5523
9
6633
10
6500
104
109
88
33
331
437
375
283
275
252
419
194
402
353
801
1038
915
640
733
538
510
402
758
728
1111
430
717
1525
1045
594
459
957
834
969
1807
1761
1715
885
1770
1118
1145
1173
1575
1333
2271
1508
1921
1931
1779
1173
874
1835
1567
1459
2207
3161
2674
1653
3067
2507
1618
1864
3175
2315
3054
2949
2461
3454
3028
2949
1601
2337
2293
2315
3014
3369
4225
3600
4291
3690
2625
2315
3028
2834
4791
4176
3586
4062
3541
3735
2102
2809
2936
3469
3858
4459
4159
4545
4702
3951
3858
3355
3271
3600
4827
5233
5120
4562
3858
4917
3243
3935
3873
4274
4936
4755
4954
5120
6500
5027
5702
4374
3469
4827
4632
5824
6030
6072
6949
5662
6880
5139
5445
7957
6722
7684
7418
6457
10198
6135
5742
9645
7442
68
52
86
18
81
41
68
101
84
94
134
22
107
249
104
155
269
184
392
280
317
5926
5824
4685
6745
5196
5139
4649
5504
8522
6284
6391
6522
5988
9004
8160
7228
7041
Table 17 G. morhua, Greenland (total). Weighted mean weight (g., by stratum abundance) at age 1-10
years, 1982, 1984-2003. () Incomplete sampling.
YEAR
1982
1983
(1984)
1985
1986
1987
1988
1989
1990
1991
(1992)
1993
(1994)
1995
1996
1997
1998
1999
2000
2001
2002
2003
1
44
2
230
3
572
4
975
5
1798
6
2293
7
3148
8
4324
9
5967
10
6767
104
97
73
36
61
37
44
58
63
64
44
68
42
68
56
82
82
83
46
102
331
225
325
237
214
164
128
172
237
141
126
244
104
180
155
294
207
297
267
350
801
612
603
697
471
437
359
375
459
644
518
426
594
1000
1045
594
441
753
659
807
1807
1173
1326
920
1032
845
722
801
1208
1281
1980
1427
1864
1761
1761
1173
862
1779
1541
1403
2207
2081
1921
1259
1550
1584
1025
1318
1644
2154
2962
2949
2461
3454
2923
2949
1601
2271
2293
2293
3014
2239
2822
2315
2822
2250
2217
1941
3028
2784
4791
4176
3586
4062
3541
3705
2102
2809
2936
3454
3858
3920
3216
2649
3858
3951
3299
3243
3041
3600
4738
5233
5120
4562
3858
4917
3243
3935
3873
4274
4936
4374
4738
3541
3285
4791
5702
4014
3469
4827
4632
5702
5484
6072
4614
5046
6880
5139
5445
6219
6177
6435
6522
6219
10198
6135
5742
9645
7442
5926
5824
4685
6745
5196
5139
4649
5504
8522
6284
6391
6522
5988
9004
8160
7228
7041
Table 18 G. morhua, Greenland. Linear multiple regression analyses for length at ages 3-6, models
are illustrated in Figure 7.
dependent variable f(x,y)= length at age (cm)
independent variable x = temperature (°C)
independent variable y = ration of fish distributed off East Greenland
Age Group
3
4
5
6
function
f(x,y)=26.145+3.300x+1.163y
f(x,y)=38.514+1.995x+7.991y
f(x,y)=50.936+0.325x+12.903y
f(x,y)=56.569+1.164x+9.408y
n
21
21
21
21
13
r²
0.43
0.56
0.60
0.39
Greenland
Str. 1.1
Str. 7.1
Str. 1.2
Str. 7.2
Str. 6.1
Str. 2.1
Str. 6.2
Str. 2.2
Str. 3.1
Station (kg/0.5h)
Str. 3.2
Str. 5.1
Str. 5.2
Str. 4.1
0 1196
Str. 4.2
2393
Fig. 1 Stratification of the survey area as specified in Table 2, positions of hauls carried out in 2003
and catches of cod.
14
900000
Abundance Index (1000)
East
800000
West
700000
Spawning Stock
600000
500000
400000
300000
200000
100000
0
1982 1984* 1986 1988 1990 1992* 1994* 1996 1998 2000 2002
Fig. 2 G. morhua. Aggregated survey abundance indices for West and East Greenland and spawning
stock size as listed in Tables 4 and 10, 1982-2003. *) incomplete survey coverage.
800000
East
Biomass Index (tons)
700000
West
Spawning Stock
600000
500000
400000
300000
200000
100000
0
1982 1984* 1986 1988 1990 1992* 1994* 1996 1998 2000 2002
Fig. 3 G. morhua. Aggregated survey biomass indices for West and East Greenland and spawning
stock size as listed in Tables 5 and 11, 1982-2003. *) incomplete survey coverage.
800000
800000
y = 141.82x + 31830
R2 = 0.0453
y = 16.636x - 9337.1
R2 = 0.95
700000
600000
600000
500000
500000
age 3
age 3
700000
400000
400000
300000
300000
200000
200000
100000
100000
0
0
0
200
400
600
800
1000
1200
1400
0
age 0
10000
20000
30000
40000
50000
age 1
Fig. 4 G. morhua. Use of 0 and 1 age group indices to predict year class strength at age 3. The x
indicate the 2001, 2002 and 2003 year classes at age 0 and the 2001 and 2002 at age 1, respectively.
Values are listed in Table 8.
15
WEST
AGE 1
26.0
24.0
85.0
EAST
TOTAL
80.0
TOTAL
75.0
20.0
Length (cm)
Length (cm)
22.0
18.0
16.0
70.0
65.0
60.0
55.0
14.0
50.0
12.0
45.0
10.0
40.0
1982
1984
1986 1988
1990
1992 1994
1996
1998 2000
2002
1982
1984
1986
1988
WEST
AGE 2
40.0
1990
1992
1994
1996
1998
2000
2002
WEST
AGE 7
EAST
90.0
EAST
TOTAL
85.0
TOTAL
35.0
80.0
Length (cm)
Length (cm)
WEST
AGE 6
EAST
30.0
25.0
75.0
70.0
65.0
60.0
55.0
20.0
50.0
15.0
45.0
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
WEST
AGE 3
1990
1992
1994
1996
1998
2002
WEST
AGE 8
EAST
60.0
2000
EAST
TOTAL
TOTAL
95.0
55.0
85.0
Length (cm)
Length (cm)
50.0
45.0
40.0
75.0
65.0
35.0
55.0
30.0
25.0
45.0
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
WEST
AGE 4
65.0
1990
1992
1994
1996
1998
2000
2002
WEST
AGE 9
EAST
110.0
EAST
TOTAL
105.0
TOTAL
60.0
100.0
95.0
Length (cm)
Length (cm)
55.0
50.0
45.0
90.0
85.0
80.0
75.0
40.0
70.0
35.0
65.0
30.0
60.0
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1986
1988
WEST
AGE 5
80.0
75.0
1990
1992
1994
1996
1998
2000
2002
WEST
AGE 10
EAST
110.0
EAST
TOTAL
105.0
TOTAL
100.0
70.0
65.0
Length (cm)
Length (cm)
1984
60.0
55.0
50.0
95.0
90.0
85.0
80.0
75.0
45.0
70.0
40.0
65.0
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
Fig. 5 G. morhua. Weighted mean length at age 1-10 years for West, East Greenland and total as
listed in Tables 12-14, 1982-2003.
16
WEST
AGE 1
4000
Weight (g)
110
Weight (g)
TOTAL
4500
130
90
70
50
3500
3000
2500
2000
30
1500
10
1000
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
WEST
AGE 2
1990
1992
1994
1996
1998
2000
2002
WEST
AGE 7
500
EAST
6000
EAST
450
TOTAL
5500
TOTAL
400
5000
350
4500
Weight (g)
Weight (g)
EAST
5000
TOTAL
300
250
200
4000
3500
3000
150
2500
100
2000
50
1500
0
1000
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
WEST
AGE 3
1990
1992
1994
1996
1998
EAST
1600
TOTAL
2000
2002
WEST
AGE 8
1800
EAST
8000
TOTAL
7000
1400
6000
Weight (g)
1200
Weight (g)
WEST
AGE 6
EAST
150
1000
800
600
5000
4000
3000
2000
400
1000
200
0
0
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
WEST
AGE 4
1992
1994
1996
1998
2000
2002
WEST
AGE 9
EAST
2500
1990
EAST
10000
TOTAL
TOTAL
9000
2000
Weight (g)
Weight (g)
8000
1500
1000
7000
6000
5000
500
4000
0
3000
1982
1984
1986
1988
1990
1992
1994
1996
1998
2002
1982
1984
1986
1988
WEST
AGE 5
1992
1994
1996
1998
8000
Weight (g)
9000
2500
2000
1500
TOTAL
7000
6000
1000
5000
500
4000
0
2002
EAST
10000
3000
2000
WEST
11000
TOTAL
3500
1990
AGE 10
EAST
4000
Weight (g)
2000
3000
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
Fig. 6 G. morhua. Weighted mean weight at age 1-10 years for West, East Greenland and total as
listed in Tables 15-17, 1982-2003.
17
65
75
60
55
45
1981 1984
1996 1999 2002
Length at age 4
Model
85
1987 1990 1993
1996 1999 2002
Length at age 6
Model
80
Length (cm)
Length (cm)
65
50
60
55
50
45
40
1981 1984
Length at age 5
Model
70
Length (cm)
Length (cm)
Length at age 3
50
Model
48
46
44
42
40
38
36
34
32
30
1981 1984 1987 1990 1993
75
70
65
60
1987 1990 1993
55
1981 1984
1996 1999 2002
1987 1990 1993
1996 1999 2002
Fig. 7 G. morhua, Greenland. Multiple linear regression models for length at ages 3-6 based on near
bottom temperature and the ratio of fish distributed off East Greenland. The models are specified in
Table 18.
18

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