Based on otolith microchemistry
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O rkney/ S h etlan d Buchan Banks Downs D o g g e r B ank (fo rm e r s p aw ning ground) N o rth Sea IC E S A re a IV Skaggerak ICES A re a IIIa E n g lish Channel IC E S A rea V IId 0 4000 8000 12000 16000 LAI 1970 1975 1980 1985 1990 1995 2000 2005 Year 0 4000 8000 12000 16000 LAI 1970 1975 1980 1985 1990 1995 2000 2005 O rkn ey/S h etlan d Buchan B anks Downs
description
Based on otolith microchemistry. Spawning stocks in fishing areas. Based on otolith microchemistry. Nursery grounds supplying spawning locations. the populations e.g. 1) How many populations? 2) Spatial and temporal distributions 3) Mixing hypothesis, e.g. diffusion/overlap - PowerPoint PPT Presentation
Transcript of Based on otolith microchemistry
Orkney/Shetland
Buchan
Banks
Downs
Dogger Bank(former spawning ground)
North SeaICES Area IV
Skaggerak ICES Area IIIa
English Channel ICES Area VIId
0
4000
8000
12000
16000
LA
I1970 1975 1980 1985 1990 1995 2000 2005
Year
0
4000
8000
12000
16000
LA
I1970 1975 1980 1985 1990 1995 2000 2005
Orkney/Shetland Buchan
Banks Downs
-12 -11 -10 -9 -8 -7 -6 -5 -4 -3 -250
51
52
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VIIa(S)
VIIgVIIj
VIIb
VIaS
VIaN
VIIa(N)
Clyde
VIaN
0
100000
200000
300000
400000
500000
600000
1950 1960 1970 1980 1990 2000 2010
Year
SS
B (
ton
nes
)
VIaN
0
2000000
4000000
6000000
8000000
10000000
12000000
1950 1960 1970 1980 1990 2000 2010
Year
Re
cru
itm
ent
(th
ou
san
ds
)
VIaS
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
1965 1970 1975 1980 1985 1990 1995 2000 2005
Year
Re
cru
itm
ent
(th
ou
san
ds
)
VIaS
0
50000
100000
150000
200000
250000
300000
350000
1950 1960 1970 1980 1990 2000 2010
Year
SS
B (
ton
nes
)
VIIaN
0
5000
10000
15000
20000
25000
30000
35000
40000
1950 1960 1970 1980 1990 2000 2010
Year
SS
B (
ton
nes
)
VIIaN
0
100000
200000
300000
400000
500000
600000
700000
800000
1950 1960 1970 1980 1990 2000 2010
Year
Re
cru
itm
ent
(th
ou
san
ds
)
Celtic Sea VIIg & j
0
20000
40000
60000
80000
100000
120000
1950 1960 1970 1980 1990 2000 2010
Year
SS
B (
ton
nes
)
Celtic Sea VIIg & j
0
200000
400000
600000
800000
1000000
1200000
1950 1960 1970 1980 1990 2000 2010
Year
Re
cru
itm
ent
(th
ou
san
ds
)
Western herring
0
100000
200000
300000
400000
500000
600000
700000
800000
1950 1960 1970 1980 1990 2000 2010
Year
Sp
awn
ing
Sto
ck B
iom
ass
(t)
Western herring
0
2000000
4000000
6000000
8000000
10000000
12000000
14000000
1950 1960 1970 1980 1990 2000 2010
Year
Re
cru
its
(th
ou
san
ds
)
Western stocks
0
100000
200000
300000
400000
500000
600000
700000
800000
1950 1960 1970 1980 1990 2000 2010
Year
SS
B (
ton
nes
)
Western Stocks
0
2000000
4000000
6000000
8000000
10000000
12000000
14000000
1950 1960 1970 1980 1990 2000 2010
Year
Rec
ruit
men
t (t
ho
usa
nd
s)
All western stocksindividual SSB and R
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
0 100000 200000 300000 400000 500000
SSB (t)
Re
cru
itm
en
t (t
ho
usa
nd
s)
VIaN
VIaS
VIIaN
CS VIIg&j
Celtic Sea
Dingle
Dingle
Donegal
DonegalClyde
Clyde
Irish Sea
Irish Sea
Skye
Skye
Cape Wrath
Celtic Sea
Dingle
RosamhilRosamhil
Clyde
C ape W rath
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
West of Scotland West of Ireland Irish Sea Celtic Sea
Mixed aggregation sampling areas
Cape Wrath
Skye
Irish Sea
Clyde
Donegal
Rosamhil
Dingle
Celtic SeaSp
aw
nin
g G
rou
ps
(L
oc
ati
on
s)
Based on otolith microchemistry
Spawning stocks in fishing areas
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Juve
nile
pop
ulati
ons
Spawning sites
Stanton Bank
Minch
Scottish Sea Lochs
West Irish Sea
East Irish Sea
Celtic Sea
Based on otolith microchemistry
Nursery grounds supplying spawning locations
the populations e.g.1) How many populations?2) Spatial and temporal distributions3) Mixing hypothesis, e.g. diffusion/overlap4) Biological characteristics (SRR, growth rate, natural mortality, fecundity, …)5) Current status, virgin biomass, BMSY, etc…6) Variability in the above, trends/random/stationarity/non-stationarity and the fisheries e.g.1) Temporal and spatial overlap with stocks2) Selectivity by age3) Management measures
1
2
3
4
1
2
3
4
Adult mixing (ages >2) Juvenile mixing (ages <2)
1
2
3
4
1
2
3
4
Adult mixing (ages >2) Juvenile mixing (ages <2)
1. No. Populations - 4
2. Spatial distributions of stocks
1
2
3
4
Fisheries on adults
F1
F2
F3?
1
2
3
4
Fisheries on adults
F1
F2
F3?
1
2
3
4
Fisheries on adults
F1
F2
F3?
1
2
3
4
Fisheries on adults
F1
F2
F3?
TAC 1
TAC 2
TAC 3
TAC 4
