longline cpue standardization: iattc 2006
DESCRIPTION
Longline CPUE standardization: IATTC 2006. Simon Hoyle and Mark Maunder. Introduction. Longline fisheries Indices of abundance Statistical methods Results & discussion Model selection Diagnostics CPUE indices Compare with last year Parameter estimates. Longline fisheries. Northern. - PowerPoint PPT PresentationTRANSCRIPT
Longline CPUE standardization: IATTC 2006
Simon Hoyle and Mark Maunder
Introduction
• Longline fisheries• Indices of abundance• Statistical methods• Results & discussion
– Model selection– Diagnostics– CPUE indices– Compare with last year– Parameter estimates
Longline fisheries
10
40
30
20
10
0
10
20
30
40
150 140 130 120 110 100 90 80 70
11
12
6
5
1, 13
2, 143, 15
4, 16 7
9
8
Baitboat Unassociated Longline
DolphinFloating Objects
Northern
Southern
Indices of abundance
• Standardized CPUE assumed proportional to abundance
• Japanese longline data, 1975 – 2004– Provided by SPC
• Catch in numbers, effort in hooks• Methods
– 2005 – delta gamma GLM– 2003-2004 – neural networks– 1999-2002 – regression trees
Statistical methods
• Strata defined as 5º square / HBF category– Only strata with at least 5 non-zero catches are
included
• Delta lognormal model
• w = g(Year.qtr, Lat.Long, HBF, effort)
• f(y) = h(Year.qtr, Lat.Long, HBF)
, 0,Pr( )
(1 ) ( ) otherwise
w yY y
w f y
Change from last year
• In 2005– Used delta gamma model– Didn’t include effort in delta component of
GLM
• Delta lognormal fit the data better (AIC)
• Change makes very little difference to results
Catch and effort (northern)
Northern fishery
0
5
10
15
20
25
30
35
1975 1980 1985 1990 1995 2000 2005
Year
Cat
ch (
thou
sand
s)
0
20
40
60
80
100
120
140
Eff
ort
(tho
usan
ds o
f ho
oks)
Yellowfin catch
Bigeye catch
Effort (hooks)
Catch and effort (southern)
Southern fishery
0
50
100
150
200
250
300
1975 1980 1985 1990 1995 2000 2005
Year
Cat
ch (
thou
sand
s)
0
100
200
300
400
500
600
Eff
ort
(tho
usan
ds o
f ho
oks)
YellowfinBigeyeEffort (hooks)
Un-standardized data – proportion zero & nonzero CPUE
Yellowfin northern
0
0.2
0.4
0.6
0.8
1
1975 1980 1985 1990 1995 2000 2005
Year
Pro
po
rtio
n n
on
-zer
o
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45
No
n-z
ero
cat
ch p
er u
nit
eff
ort
Proportion nonzero Nonzero CPUE
Yellowfin southern
0.75
0.8
0.85
0.9
0.95
1
1975 1980 1985 1990 1995 2000 2005
Year
Pro
po
rtio
n n
on
-zer
o
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
No
n-z
ero
cat
ch p
er u
nit
eff
ort
Proportion nonzero Non-zero CPUE
Bigeye northern
0
0.2
0.4
0.6
0.8
1
1975 1980 1985 1990 1995 2000 2005
Year
Pro
po
rtio
n n
on
-zer
o
0
0.5
1
1.5
2
2.5
3
No
n-z
ero
cat
ch p
er u
nit
eff
ort
Proportion nonzero Nonzero CPUE
Bigeye southern
0.75
0.8
0.85
0.9
0.95
1
1975 1980 1985 1990 1995 2000 2005
Year
Pro
po
rtio
n n
on
-zer
o
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
No
n-z
ero
cat
ch p
er u
nit
eff
ort
Proportion nonzero Nonzero CPUE
Model selectionFishery Model Δ AICBET N yrqtr.latlong.hbf / lognormal 0
- hbf 118- latlong 6,080
BET S yrqtr.latlong.hbf / lognormal 0- hbf 817- latlong 13,575gamma 94,592
YFT N yrqtr.latlong.hbf / lognormal 0- hbf 30- latlong 1,237gamma 18,745
YFT S yrqtr.latlong.hbf / lognormal 0- hbf 336- latlong 32,936gamma 136,784
Residuals for non-zero component through time
1975 1980 1985 1990 1995 2000
-15
0-1
00
-50
05
01
00
Northern bigeye
Time
Re
sid
ua
ls
1975 1980 1985 1990 1995 2000 2005
-15
0-1
00
-50
05
01
00
Northern yellowfin
Time
Re
sid
ua
ls
1975 1980 1985 1990 1995 2000 2005
-20
0-1
00
01
00
Southern bigeye
Time
Re
sid
ua
ls
1975 1980 1985 1990 1995 2000 2005
-20
00
20
04
00
Southern yellowfin
Time
Re
sid
ua
ls
Residuals for non-zero component
Southern bigeye
Residuals
De
nsi
ty
-40 -20 0 20 40
0.0
00
.02
0.0
40
.06
0.0
8
Southern yellowfin
Residuals
De
nsi
ty
-50 0 50
0.0
00
0.0
05
0.0
10
0.0
15
0.0
20
0.0
25
0.0
30
Northern bigeye
Residuals
De
nsi
ty
-40 -20 0 20 40
0.0
00
.01
0.0
20
.03
0.0
40
.05
Northern yellowfin
Residuals
De
nsi
ty
-60 -40 -20 0 20 40 60
0.0
00
.01
0.0
20
.03
Standardized CPUE - bigeye
Bigeye tuna
0
0.5
1
1.5
2
2.5
3
1975 1980 1985 1990 1995 2000 2005
Year
CP
UE
inde
x
Northern
Southern
Yellowfin tuna
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
1975 1980 1985 1990 1995 2000 2005
Year
CP
UE
inde
x
Northern
Southern
Standardized CPUE - yellowfin
Raw vs standardized CPUE
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1975 1980 1985 1990 1995 2000 2005
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
BET S raw
standardized
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
1975 1980 1985 1990 1995 2000 2005
0
0.5
1
1.5
2
2.5
3
3.5
YFT S raw
Standardized
Southern bigeye
y = -0.0051x + 11.126
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1975 1980 1985 1990 1995 2000 2005
Year
All
fac
tors
CP
UE
/ t
ime
on
ly C
PU
E
Standardized CPUE / CPUE standardized by time only
slope= -0.0051 ± 0.0006
Standardized CPUE / CPUE standardized by time only
Southern yellowfin
y = -0.0073x + 15.629
0
0.5
1
1.5
2
2.5
3
1975 1980 1985 1990 1995 2000 2005
Year
All
fac
tors
CP
UE
/ t
ime
on
ly C
PU
E
slope = -0.007 ± 003
Average HBF through time
0
2
4
6
8
10
12
14
16
18
1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003
Year
Ave
rage
hoo
ks b
etw
een
float
s by
str
atum
N
S
HBF parametersNorthern bigeye
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 2 4 6 8 10 12 14 16 18 20
Hooks between floats
Southern bigeye
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 2 4 6 8 10 12 14 16 18 20
Hooks between floats
Northern yellowfin
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 5 10 15 20 25
Hooks between floats
Southern yellowfin
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 5 10 15 20 25
Hooks between floats
Bigeye south12.5
7.5
2.5
-2.5
-7.5
-12.5
-17.5
-22.5
-27.5
-32.5
-37.5147.5 142.5 137.5 132.5 127.5 122.5 117.5 112.5 107.5 102.5 97.5 92.5 87.5 82.5 77.5 72.5
Lat
Long
2.25-2.5
2-2.25
1.75-2
1.5-1.75
1.25-1.5
1-1.25
0.75-1
0.5-0.75
0.25-0.5
0-0.25
Yellowfin south
12.5
7.5
2.5
-2.5
-7.5
-12.5
-17.5
-22.5
-27.5
-32.5147.5 142.5 137.5 132.5 127.5 122.5 117.5 112.5 107.5 102.5 97.5 92.5 87.5 82.5 77.5 72.5
Lat
Long
3.5-4
3-3.5
2.5-3
2-2.5
1.5-2
1-1.5
0.5-1
0-0.5