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БИОЛОГИЯ, ПРОМЫСЕЛ И ДИНАМИКА ЗАПАСОВ ЧЕРНОГО

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North-East Arctic Haddock
Melanogrammus aeglefinus (Linne)
Year-class abundance of haddock aged 3 (1) and
haddock annual catch (2) in 1947-1995
1200
350
1000
300
600
150
400
100
200
50
0
1
2
1995
1991
1987
1983
1979
1975
1971
1967
1963
1959
1955
1951
0
1947
mln.
200
th.t
250
800
1
2
1995
1992
temperature
2.4
1989
0
1986
2.8
1983
200
1980
3.2
1977
400
1974
3.6
1971
600
1968
4.0
1965
800
1962
4.4
1959
1000
1956
4.8
1953
1200
1950
mln.
Long-term fluctuations of the mean annual temperature
in the main stream of the Murman Current along the
Kola Section (St.3-7) in 0-200 m layer and the abundance
of the Northeast Arctic haddock aged 3 in 1950-1995
Year-class distribution of the Northeast Arctic haddock with
different strength depending on sea temperature in 1950-1995
Year-classes
temperature
total
low
medium
high
weak
12
9
6
27
medium
1
1
3
5
strong
-
8
6
14
Number of year-classes
13
18
15
46
% of weak year-classes
92
50
40
59
% of medium year-classes
8
6
20
11
% of strong year-classes
-
44
40
30
Abundance of year-classes aged 3(1) and haddock
spawning biomass (2) in 1950-1995
1200
250
1000
200
th.t
150
600
100
400
50
200
1
2
1995
1992
1989
1986
1983
1980
1977
1974
1971
1968
1965
1962
1959
1956
0
1953
0
1950
mln.
800
1200
1000
800
600
400
200
0
250
200
100
50
1
2
1995
1990
1985
1980
1975
1970
1965
1960
1955
0
th.t
150
1950
mln.
Long-term variations of year-class abundance of
haddock aged 3 (1) and the spawning stock
(individuals aged 6-8) (2) in 1950-1995
Strength of the year-classes aged 3 (1), as well as the
portion of individuals aged 3-5 (2) and 6-8 (3) in the
spawning stock of haddock in 1963-1995
1200
100
1000
80
60
600
%
40
400
20
200
1
2
3
1995
1993
1991
1989
1987
1985
1983
1981
1979
1977
1975
1973
1971
1969
1967
0
1965
0
1963
mln.
800
Distribution of haddock year-classes with
different strength depending on the size of the
spawning stock of individuals aged 6-8
(thou.t) in 1950-1995
Year-classes
Spawning stock
total
low
medium
high
weak
16
7
4
27
medium
1
1
3
5
strong
2
7
5
14
Number of year-classes
19
15
12
46
% of weak year-classes
84
47
33
59
% of medium year-classes
5
7
25
11
% of strong year-classes
11
47
42
30
mln.
1
2
1995
1992
1989
1986
1983
1980
1977
1974
1971
1968
1965
1962
1959
1956
1953
1400
1200
1000
800
600
400
200
0
1950
mln.
Year-class abundance of haddock aged 3 (1) and
total abundance of immature individuals aged 3 and
older in the year of the appearance of year-classes
(2) in 1950-1995
Distribution of haddock year-classes with different strength
depending on the density of population in 1950-1995, in
normal and warm years
Year-classes
Number of stock
total
low
medium
high
weak
5
5
8
20
medium
3
1
1
5
strong
8
6
-
14
Number of year-classes
18
12
9
39
% of weak year-classes
38
42
89
51
% of medium year-classes
17
8
11
13
% of strong year-classes
44
50
-
36
1. Haddock is characterized by a very great difference in abundance of some
year-classes and, as a result, by very abrupt year-to-year variations of
commercial and spawning stock size.
2. In the most of cases, during the first years of haddock year-class life, water
temperature was a reliable indicator of strength at age 3. In anomalous cold
years, all the generations of haddock were very poor despite the level of
spawning stock, density of population and other factors. In the normal and
warm years, the effect of water temperature on haddock juvenile survival and
year-class abundance becomes weaker.
3. Haddock year-class abundance, to a great extent, depends on the spawning
stock size and structure. The individuals aged 6-8 spawning two and more times
have the maximal influence on strength of haddock year-classes.
4. The immature stock abundance of haddock distributed in the Barents Sea
also has an impact on the strength of the year-classes. The relationship of the
year-class strength and the density of population is especially noticeable in the
warm years, when the role of abiotic conditions was high.
Haddock spawning stock dynamics and deviations in
the stock size as compared to the previous year level
250
TOTSPBIO
200
th.t
150
100
50
0
1950
1953
1956
1959
1962
1965
1968
1971
1974
100
75
50
25
0
-25
-50
TOTSPBIO
1977
1980
1983
1986
1989
1992
1995
1998
2001
Haddock commercial stock dynamics and
deviations in the stock size as compared to the
previous year level
900
800
TOTALBIO
700
Th.t
600
500
400
300
200
100
0
1950 1953 1956 1959 1962 1965 1968 1971 1974 1977 1980 1983 1986 1989 1992 1995 1998 2001
225
200
175
150
125
100
75
50
25
0
-25
-50
TOTBIO
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