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OVERVIEW OF TUNA FISHERIES IN THE WESTERN AND CENTRAL PACIFIC OCEAN, INCLUDING ECONOMIC CONDITIONS – 2019

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Provides a description of the major tuna fisheries in the WCPFC Statistical Area highlighting activities during the most recent calendar year (2019) and covering the most recent summary of catch estimates by gear and species, including economic conditions.
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i
SCIENTIFIC COMMITTEE
SIXTEENTH REGULAR SESSION
Online Meeting
11 20 August 2020
OVERVIEW OF TUNA FISHERIES IN THE WESTERN AND CENTRAL PACIFIC
OCEAN, INCLUDING ECONOMIC CONDITIONS 2019
WCPFC-SC16-2020/GN IP-1 rev 3
Paper prepared by
Peter Williams¹ and Thomas Ruaia2
Revision 1
- Added Figure A11 in the APPENDIX in response to a WCPFC16 request from EU and PNA to include
a graph showing the breakdown of catches by national waters and high seas.
Revision 2
- Updated Figure A1 to include the most recent 2020 VMS data.
- Added Figure A12 in the APPENDIX in response to a request from the SC16 online forum for
cumulative South Pacific Albacore longline fishery effort by month, 2016-2020 (as measured by VMS)
- Slight modifications made in the Purse seine economics section (3.8.1 Prices Yellowfin)
Revision 3
- A further updated to Figure A1 after resolving a gap in VMS data for late May/early June 2020
¹ Pacific Community (SPC), Ocean Fisheries Programme (OFP), Noumea, New Caledonia
2 Pacific Islands Forum Fisheries Agency (FFA), Honiara, Solomon Islands
ii
ABSTRACT
This paper provides a broad description of the major fisheries in the WCPFC Statistical Area (WCP-
CA) highlighting activities during the most recent calendar year (2019) and covering the most recent
summary of catch estimates by gear and species.
The provisional total WCPCA tuna catch for 2019 was estimated at 2,961,059 mt, the highest on
record, at around 76,000 mt higher than the previous record catch in 2014 (2,885,042 mt). The WCP
CA tuna catch (2,961,059 mt) for 2019 represented 81% of the total Pacific Ocean tuna catch of
3,656,813 mt, and 55% of the global tuna catch (the provisional estimate for 2019 is 5,403,368 mt),
both of which are records.
The 2019 WCPCA skipjack catch of 2,034,230 mt was a record and around 45,000 mt higher than
the previous record in 2014 (1,978,927 mt). The 2019 yellowfin catch (669,362 mt) was the third
highest on record, at around 44,000 mt less than the previous record in 2017. The high catches are
related to some extent to recent high catch levels from the “other” category (primarily small-scale
fisheries in Indonesia). The provisional WCP-CA bigeye catch (135,680 mt) for 2019 was lower than
the recent ten-year average and amongst the lowest over the past two decades. The 2019 WCPCA
albacore catch (121,787 mt) was higher than the 2018 catch and similar to the recent ten-year average,
but remained around 26,000 mt lower than the record catch in 2002 of 147,793 mt. The south Pacific
albacore catch in 2019 (86,706 mt), was amongst the highest for this fishery, with the record catch
taken in 2017 (93,415 mt).
The provisional 2019 purse-seine catch of 2,060,412 mt was the highest on record, but only 1,000 mt
higher than the previous record in 2014 (2,059,006 mt). The 2019 purse-seine skipjack catch (1,641,920
mt) was the highest on record, 32,000 mt higher than the previous record in 2014 (1,609,784 mt). The
proportion of skipjack tuna (80%) in the 2019 purse seine tuna catch is the highest since the fishery was
established in the 1960s. The 2019 purse-seine catch for yellowfin tuna (364,571 mt; 18%) was over
130,000 mt lower than the record catch in 2017 (498,822 mt) but still amongst the highest annual catches
for this fishery. The provisional catch estimate for bigeye tuna for 2019 (50,819 mt) was the lowest
since 2003, and the proportion of bigeye tuna (2%) represented in the purse seine tuna catch, the lowest
since 1980. The relatively low bigeye tuna catch in 2019 appears to be related to both (i) a lower
proportion of associated sets in 2019, and (ii) a lower proportion of bigeye tuna in the associated-set
tuna species composition in 2019.
The provisional 2019 pole-and-line catch (183,193 mt) was lower than the 2018 catch (231,155 mt)
and amongst the lowest annual catches since the mid-1960s, due to reduced catches in both the Japanese
and the Indonesian fisheries.
The provisional WCPCA longline catch (273,550 mt) for 2019 was at the average level for the past
five years. The WCPCA albacore longline catch (95,280 mt, 35% of total catch) for 2019 was slightly
higher than the recent ten-year average, and only 6,000 mt lower than the record of 101,820 mt attained
in 2010. The provisional bigeye catch (68,371 mt, 25% of total catch) for 2019 was slightly lower than
the recent ten-year average, and well down on the bigeye catch levels experienced in the 2000s (e.g. the
2004 longline bigeye catch was 99,705 mt). The yellowfin catch for 2019 (104,440 mt, 38% of total
catch) was the highest catch since 1980 (which was a record for this fishery at 125,113 mt).
The 2019 South Pacific troll albacore catch (3,425 mt) was the highest catch since 2008 (3,502 mt).
The New Zealand troll fleet (144 vessels catching 2,272 mt in 2019) and the United States troll fleet
(16 vessels catching 475 mt in 2019) accounted for all of the 2019 albacore troll catch.
Market prices in 2019 were mixed with prices for purse seine caught product declining for the second
consecutive year with, for example, Thai imports averaging $1,399/mt over 2019 down 15% from 2018
iii
levels which were 8% lower than the 2017 average of $1,782/mt. Yaizu prices for pole and line caught
skipjack also saw significant declines.
Prices for longline caught yellowfin were mixed with prices for fresh imports into the US and Japan
declining while the Japan fresh price at selected ports was marginally higher. Prices for longline caught
bigeye in 2019 declined across the selected markets. Thai imports prices for albacore continue to
increase to reach a record level of $3,960/mt in 2019. Albacore prices in 2020 have come of their recent
highs but remained at relatively high levels with Thai imports averaging $3,744/mt during May.
The total estimated delivered value of the tuna catch in the WCP-CA declined by 7% to $5.8
billion in 2019. The value of the purse seine catch declined 6% to $3.02 billion and accounted for 52%
of the total value of the tuna catch. The value of the longline fishery decreased 7% to $1.61 billion
accounting for 28% of the total value of the tuna catch. The value of the pole and line catch declined
21% to $390 million as catch declined the same amount following a 35% increase in 2018 while with
the value of the catch by other gears decline marginal marginally to $740 million. The 2019 WCPCA
skipjack catch was valued at $2.93 billion, the yellowfin catch at $1.7 billion, the bigeye catch at $692
million, and the albacore catch increased to $438 million its highest level since 2012.
Economic conditions in 2019 in the purse seine, tropical longline and southern longline fisheries
of the WCP-CA showed mixed results. The tropical purse seine fishery, despite falls in prices, saw the
continuation of good economic conditions as fuel prices declined and catch rates continued to increase.
In the southern longline fishery after a recent improvements economic conditions have again
deteriorated, as catch rates decline, despite relatively high fish prices and average costs. Economic
conditions for the tropical longline fishery continue to remain below the 20-year average with CPUE
and fish prices below their 20-year averages.
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CONTENTS
1. INTRODUCTION .......................................................................................................................... 1
2. TOTAL TUNA CATCH AND CATCH VALUE FOR 2019 ........................................................ 2
3 WCPCA PURSE SEINE FISHERY ............................................................................................ 4
3.1 Historical Overview ................................................................................................................................. 4
3.2 Provisional catch estimates, fleet size and effort (2019) .......................................................................... 5
3.3 Environmental conditions ......................................................................................................................... 7
3.4 Distribution of fishing effort and catch .................................................................................................... 8
3.5 Catch per unit of effort ........................................................................................................................... 14
3.6 Species/Size composition of the catch.................................................................................................... 16
3.7 Seasonality ............................................................................................................................................. 18
3.8 Prices, catch value and overall economic conditions ............................................................................. 20
3.8.1 Prices ............................................................................................................................................................. 20
3.8.2 Catch Value ................................................................................................................................................... 21
3.8.3 Economic Conditions in the tropical purse seine fishery ............................................................................... 21
4 WCPCA POLE-AND-LINE FISHERY ..................................................................................... 23
4.1 Historical Overview ............................................................................................................................... 23
4.2 Catch estimates (2019) ........................................................................................................................... 23
4.3.1 Prices ............................................................................................................................................................. 24
4.3.2 Catch Value ................................................................................................................................................... 24
5 WCPCA LONGLINE FISHERY ............................................................................................... 25
5.1 Overview ................................................................................................................................................ 25
5.2 Provisional catch estimates and fleet sizes (2019) ................................................................................. 26
5.3 Catch per unit effort ............................................................................................................................... 27
5.4 Geographic distribution .......................................................................................................................... 27
5.5 Prices, catch value and overall economic conditions ............................................................................. 30
5.5.1 Prices ............................................................................................................................................................. 30
5.5.2 Catch Value ................................................................................................................................................... 32
5.5.3 Economic conditions ..................................................................................................................................... 33
6 SOUTH-PACIFIC TROLL FISHERY ........................................................................................ 35
6.1 Overview ................................................................................................................................................ 35
6.2 Provisional catch estimates (2019) ......................................................................................................... 35
7 OTHER FISHERIES .................................................................................................................... 36
7.1 Large-fish Handline Fishery ................................................................................................................... 36
7.2 Small-scale troll and hook-and-line Fishery ........................................................................................... 36
7.3 Small-scale gillnet Fishery ..................................................................................................................... 37
8. SUMMARY OF CATCH BY SPECIES...................................................................................... 38
8.1 SKIPJACK ............................................................................................................................................. 38
8.2 YELLOWFIN......................................................................................................................................... 41
8.3 BIGEYE ................................................................................................................................................. 44
8.4 SOUTH PACIFIC ALBACORE ............................................................................................................ 48
8.5 SOUTH PACIFIC SWORDFISH .......................................................................................................... 51
8.6 OTHER BILLFISH ................................................................................................................................ 55
8.6.1 Blue Marlin ................................................................................................................................................... 55
8.6.2 Black Marlin .................................................................................................................................................. 56
8.6.3 Striped Marlin ............................................................................................................................................... 57
8.6.4 North Pacific Swordfish ................................................................................................................................ 58
8.7 NORTH PACIFIC ALBACORE ........................................................................................................... 59
8.8 NORTH PACIFIC BLUEFIN ................................................................................................................ 59
References ............................................................................................................................................. 60
APPENDIX - Additional Information .................................................................................................. 61
1
1. INTRODUCTION
The tuna fishery in the Western and Central Pacific Ocean is diverse, ranging from small-scale artisanal operations
in the coastal waters of Pacific states, to large-scale, industrial purse-seine, pole-and-line and longline operations
in both the exclusive economic zones of Pacific states and on the high seas. The main species targeted by these
fisheries are skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacares), bigeye tuna (T. obesus)
and albacore tuna (T. alalunga).
This review provides a broad description of the major fisheries in the WCPFC Statistical Area (WCPCA; see
Figure 1), highlighting activities during the most recent calendar year 2019. The review draws on the latest catch
estimates compiled for the WCPCA, found in Information Paper WCPFCSC16-ST IP1 (Estimates of annual
catches in the WCPFC Statistical Area OFP, 2020). Where relevant, comparisons with previous years' activities
have been included, although data for 2019, for some fisheries, are provisional at this stage.
This paper includes sections covering each target tuna species, blue marlin (Makaira mazara), black marlin
(Istiompax indica), striped marlin (Kajikia audax) and swordfish (Xiphias gladius) catch in the WCPCA tuna
fisheries and an overview of the WCPCA tuna fisheries by gear, including economic conditions in the main
fisheries. In each section, the paper makes some observations on recent developments in each fishery, with
emphasis on 2019 catches relative to those of recent years, but refers readers to the SC16 National Fisheries
Reports, which offer more detail on recent activities at the fleet level.
Additional tabular and graphical information that provide more information related to the recent condition of the
fishery and certain WCPFC Conservation and Management Measures (CCMs) have been provided in an
APPENDIX.
This overview now attempts to include brief summaries of several fisheries in the north Pacific Ocean, including
those fisheries catching albacore tuna, Pacific bluefin tuna (T. orientalis), striped marlin and swordfish.
Information on these fisheries may be expanded in future reviews, depending on the availability of more complete
data.
Figure 1.1 The western and central Pacific Ocean (WCPO), the
eastern Pacific Ocean (EPO) and the WCPFC Convention Area
(WCPCA in dashed lines)
Wester n and central
Pacific Ocean
Eastern Pacific Ocean
20S
40S 40N 60N
20N
0
60S
100E 120E
110E 130E
140E 160E
150E 170E
180 160W
170W 150W
140W 120W
130W 110W 90W
100W 80W
70W
50S
30N 10S010N
50N 30S
2
2. TOTAL TUNA CATCH AND CATCH VALUE FOR 2019
Annual total catches of the four main tuna species (skipjack, yellowfin, bigeye and albacore) in the WCPCA
increased steadily during the 1980s and 1990s with the purse seine fleet clearly the dominant fishery in terms of
catch volume. The increasing trend in total tuna catch continued through to 2009, followed by two years (2010-
2011) of reduced catches, before returning to record levels in successive years over the period 20122014. Catches
in the period 20152017 were lower than 2014, but have since increased again (Figure 2.1 and Figure 2.2).
The provisional total WCPCA tuna catch for 2019 was estimated at 2,961,059 mt, the highest on record, at around
76,000 mt higher than the previous record catch in 2014 (2,885,042 mt). For 2019, the purse seine fishery
accounted for a catch of 2,060,412 mt (70% of the total catch), with pole-and-line taking an estimated 183,193
mt (6%), the longline fishery an estimated 273,550 mt (9%), and the remainder (15%) taken by troll gear and a
variety of artisanal gears, mostly in eastern Indonesia and the Philippines. The WCPCA tuna catch (2,961,059
mt) for 2019 represented 81% of the total Pacific Ocean tuna catch of 3,656,813 mt, and 55% of the global tuna
catch (the provisional estimate for 2019 is 5,403,368 mt), both of which are records.
Figure 2.1 Catch (mt) of albacore, bigeye, skipjack and yellowfin in the WCPCA, by longline, pole-and-
line, purse seine and other gear types
Figure 2.2 Catch (mt) of albacore, bigeye, skipjack and yellowfin in the WCPCA.
The 2019 WCPCA catch of skipjack (2,034,230 mt 69% of the total catch) was a record at around 45,000 mt
more than record in 2014 (1,978,927 mt). The WCPCA yellowfin catch for 2019 (669,262 mt 23%) was the
third highest recorded (44,000 mt lower than the record catch of 2017); the past four years have been the highest
annual yellowfin catches. The WCPCA bigeye catch for 2019 (135,680 mt 5%) was amongst the lowest for
the past 20 years. The 2019 WCPCA albacore
1
catch (121,787 mt 4%) was higher than the 2018 catch and
similar to the recent ten-year average, but remained around 26,000 mt lower than the record catch in 2002 of
147,793 mt.
1
includes catches of north and south Pacific albacore in the WCPCA, which comprised 82% of the total Pacific Ocean albacore catch of 148,350 mt in
2019; the section 8.4 “Summary of Catch by Species – South Pacific Albacore” is concerned only with catches of south Pacific albacore (86,706 mt in 2019),
which made up approximately 59% of the Pacific albacore catch in 2019.
0
400,000
800,000
1,200,000
1,600,000
2,000,000
2,400,000
2,800,000
3,200,000
1960
1962
1964
1966
1968
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
2016
2018
Catch (mt)
PURSE SEINE
OTHER
POLE-AND-LINE
LONGLINE
0
400,000
800,000
1,200,000
1,600,000
2,000,000
2,400,000
2,800,000
3,200,000
1960
1962
1964
1966
1968
1970
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
2016
2018
Catch (mt)
SKIPJACK
YELLOWFIN
BIGEYE
ALBACORE
3
In 2019 the value of the provisional total WCPCA tuna catch was around $5.8 billion
2
about 7% lower than
in 2018. In 2019, the purse seine fishery is valued at about $3.02 billion, 52% of the total value of the tuna catch.
The value of the longline fishery in 2019 is estimated to be at $1.61 billion and accounts for 28% of the total value
of the tuna catch. The value of the pole and line catch continued to decline to be at $390 million while the catch
by other gears was valued at $740 million.
Figure 2.3 Catch value of albacore, bigeye, skipjack and yellowfin in the WCPCA, by longline, pole-and-
line, purse seine and other gear types.
The value of the 2019 WCPCA skipjack catch (US$2.93 billion) was 5% lower than for 2018 and accounted
for 51% of the total value of the tuna catch. The WCPCA yellowfin catch in 2019 is valued at $1.7 billion, a
decline of 14% from the previous year. The value of the WCPCA bigeye catch ($692 million) was the second
highest since 2016 and accounted for 12% of the total value of the tuna catch. The value of the WCPCA albacore
catch in 2019 rose 22% to $438 million to be at its highest level since 2012 driven by an 18% increase in prices.
Figure 2.4 Catch value of albacore, bigeye, skipjack and yellowfin in the WCPCA.
2
All $ amounts refer to US dollars unless otherwise specified.
0
2
4
6
8
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
Catch value (US$ billions)
LONGLINE
POLE-AND-LINE
OTHER
PURSE SEINE
-
2
4
6
8
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
Catch value (US$ billions)
ALBACORE
BIGEYE
YELLOWFIN
SKIPJACK
4
3 WCPCA PURSE SEINE FISHERY
3.1 Historical Overview
During the mid-1980s, the purse seine fishery (400,000-450,000 mt) accounted for only 40% of the total catch,
but has grown in significance to a level now over 65% of total tuna catch volume (with more than 2,000,000 mt in
2014). The majority of the historic WCPCA purse seine catch has come from the four main Distant Water Fishing
Nation (DWFN) fleets Japan,
Korea, Chinese-Taipei and USA,
which numbered a combined 163
vessels in 1992 (Figure 3.1.1),
but declined to a low of 111
vessels in 2006 (due to
reductions in the US fleet),
before some rebound in recent
years (up to 129 vessels in 2017
and 124 vessels in 2019
3
). The
Pacific Islands fleets have
gradually increased in numbers
over the past two decades to a
level of 133 vessel in 2019
(Figure 3.3.1). The remainder of
the purse seine fishery includes
several fleets which entered the
WCPFC tropical fishery during
the 2000s (e.g. China, Ecuador,
El Salvador, New Zealand and
Spain).
The total number of purse seine
vessels was relatively stable
over the period 1990-2006 (in
the range of 180220 vessels),
but thence until 2014, the
number of vessels gradually
increased, attaining a record
level of 308 vessels in 2015,
before steadily declining since
(to 285 vessels in 2019). Further declines are expected in 2020 with the announcement of a significant reduction
in vessels from one component of the US purse seine fleet. Table A3 in the APPENDIX provides data on purse
seine vessel numbers, tuna catch and effort by set type and species in the tropical tuna purse seine fishery based
on raised logsheet data, with 274 vessels reported as operating in the tropical tuna purse seine fishery in 2019
(according to submitted logbook data).
The WCPCA purse-seine fishery is essentially a skipjack fishery, unlike those of other ocean areas. Skipjack
generally account for 6577% of the purse seine catch, with yellowfin accounting for 2030% and bigeye
accounting for only a small proportion 2-5%. Small amounts of albacore tuna are also taken in temperate water
purse seine fisheries in the North Pacific.
Features of the purse seine catch by species during the past two decades include:
Annual skipjack catches fluctuating between 600,000 and 850,000 mt prior to 2002, a significant increase in the catch
during 2002, with subsequent skipjack catches maintained well above 1,200,000 mt;
3
The number of vessels by fleet in 1992 was Japan (38), Korea (36), Chinese-Taipei (45) and USA (44) and in 2019 the number of active
vessels by fleet was Japan (36), Korea (27), Chinese Taipei (30) and USA (31). In 2019, there was an additional 36 vessels in the category
less than 200 GRT which are a part of the Japanese offshore purse seine fleet but not included here.
Figure 3.1.2 Purse seine catch (mt) of bigeye, skipjack and yellowfin and
fishing effort (days fishing and searching) in the WCPCA
(EFFORT: excludes Indonesia, Philippine and Vietnam domestic purse-seine/ringnet fleets)
0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
0
500,000
1,000,000
1,500,000
2,000,000
1972
1974
1976
1978
1980
1982
1984
1986
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
2016
2018
Estimated Effort (days)
Catch (mt)
SKIPJACK
YELLOWFIN
BIGEYE
EFFORT (days)
Figure 3.1.1 Number of purse seine vessels operating in the WCPCA
tropical fishery
(excludes Indonesia, Philippine and Vietnam domestic purse-seine/ringnet fleets)
0
50
100
150
200
250
300
1972 1976 1980 1984 1988 1992 1996 2000 2004 2008 2012 2016
Number of vessels
Distant-water
Domestic (Pacific Is.)
(Logbook and VMS)
5
Annual yellowfin catches fluctuating considerably between 300,000 and 400,000 mt, with a significant catch (record) of
498,000 mt taken in 2017. The proportion of large yellowfin in the catch is generally higher during El Niño years and
lower during La Niña years, although other factors appear to affect purse seine yellowfin catch;
Increased bigeye tuna purse seine catch estimates, coinciding with the introduction of drifting FADs (since mid-late
1990s). Significant bigeye catch years have been 2011 (73,850 mtrecord), 2013 (70,963 mt) and 2014 (69,074 mt) which
correspond to years with a relatively high proportion of associated sets, increased bigeye tuna availability to the gear,
and/or strong bigeye recruitment.
Total estimated effort shows the same increasing trend as the catch over time (Figure 3.1.2), with years of
relatively higher catch rates apparent when the effort line is clearly lower than the top of the histogram bar (i.e. in
1998 and 20062009, 20142019).
3.2 Provisional catch estimates, fleet size and effort (2019)
The provisional 2019 purse-seine catch of 2,060,412 mt was the highest on record, but only 1,000 mt higher than
the previous record in 2014 (2,059,006 mt). The 2019 purse-seine skipjack catch (1,641,920 mt) was the highest
on record, 32,000 mt higher than the previous record in 2014 (1,609,784 mt). The proportion of the skipjack tuna
(80%) catch taken by purse seine in
2019 was the highest since the fishery
was established in the 1960s. The 2019
purse-seine catch for yellowfin tuna
(364,571 mt; 18% of the total purse
seine tuna catch) was over 130,000 mt
lower than the record catch in 2017
(498,822 mt) but still amongst the
highest annual catches for this fishery.
The provisional catch estimate for
bigeye tuna for 2019 (50,819 mt) was
the lowest since 2003, and the
proportion of bigeye tuna (2%)
represented in the purse seine tuna
catch, was the lowest since 1980. The
relatively low bigeye tuna catch by
purse seine in 2019 appears to be
related to both (i) a lower proportion of
associated sets in 2019, and (ii) a lower
proportion of bigeye tuna in the
associated-set tuna species
composition in 2019.
Figure 3.2.1 compares annual purse seine effort and catches for the five main purse seine fleets operating in the
tropical WCPCA in recent years. The combined “main-fleet effort was relatively stable over the period 2010
2014, before the clear decline in effort for 2015 and then relatively stable effort levels over the period 20162019.
In contrast, catches have clearly trended upwards over this recent period, suggesting increased efficiency and, in
some instances, better catch rates; the 2019 catch for the “main fleets” is consistent with the overall record catch
and was also the highest ever. The decline in effort during 2015/2016 was related to several factors including
reduced access to fishing areas for some fleets, economic conditions and simply a choice to fish in areas outside
the WCPFC area. The maintenance of the high catch levels in 2015/2016 was due to good catch rates, in part due
to the El Nino conditions. The drop in effort from 2017 to 2019 appears to be primarily related to a decline in
vessel numbers (Figure 3.1.1).
The combined Pacific-Islands fleet has been clearly the most dominant in the tropical purse seine fishery since
2003 and unlike the other fleets shown in Figure 3.2.1, their recent catches continue to increase each year. There
was a hiatus in the Pacific-Islands fleet development in 2008 (when some vessels reflagged to the US purse-seine
fleet) but catch/effort has picked up in recent years and catch by this component of the fishery was clearly at its
Figure 3.2.1. Trends in annual effort (top) and catch (bottom)
estimates for the top five purse seine fleets operating in the
tropical WCPCA, 19962019.
0
10,000
20,000
30,000
40,000
50,000
0
4,000
8,000
12,000
16,000
20,000
24,000
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018
Total Effort (days)
Total Fleet Effort (days)
0
300,000
600,000
900,000
1,200,000
1,500,000
1,800,000
0
150,000
300,000
450,000
600,000
750,000
900,000
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018
Total Catch (1000s of mt)
Total Fleet Catch (mt)
TOTAL
Japan
Korea
Pac. Isl.
Chinese Taipei
USA
6
highest level in 2019. The combined Pacific-islands fleet catch in 2019 (851,794 mt) was close to the combined
catch from the other fleets shown in Figure 3.2.1 (combined 2019 catch for Japan, Korea, Chinese Taipei and USA
was 876,047 mt). The fleet sizes and effort by the Japanese and Korean purse seine fleets have been relatively
stable for most of this time series. Several Chinese-Taipei vessels re-flagged in 2002, dropping the fleet from 41
to 34 vessels, with fleet numbers relatively stable since. The increase in annual catch by the Pacific Islands fleet
until 2005 corresponded to an increase in vessel numbers, and to some extent, mirrors the decline in US purse
seine catch, vessel numbers and effort over this period. However, the US purse-seine fleet commenced a rebuilding
phase in late 2007, with vessel numbers more than doubling in comparison to recent years, but still below the fleet
size in the early-mid 1990s. Since 2014, the catch/effort by the Chinese Taipei, Japan and US fleets have gradually
declined while the catch/effort by the combined Pacific Islands fleet have continued to increase, related to the
reflagging of vessels from the distant-water fleets.
The total number of combined Pacific-island fleet vessels has gradually increased over the past two decades,
attaining its highest level in 2019 (133 vessels); increases in these years include the reflagging and chartering of
vessels from the Asian fleets. The combined Pacific-islands purse seine fleet covers vessels fishing under the FSM
Arrangement, bilateral agreements and domestically-based vessels and comprise vessels from the Federated States
of Micronesia (FSM; 23 vessels in 2019), Kiribati (22 vessels), Marshall Islands (11 vessels), PNG (Papua New
Guinea; 50 vessels including their chartered vessels), Solomon Islands (11 vessels), Tuvalu (1 vessel) and Vanuatu
(5 vessels). Nauru purse seine vessels (2) entered the fishery for the first time in 2018 and had nine vessels fishing
in 2019. The Cook Islands entered the purse seine fishery in 2019 with 1 newly flagged vessel.
The domestic Philippine purse-seine and ring-net fleets operate in Philippine waters and since 2013 (as was the
case prior to 2010), in the high seas pocket between Palau, Indonesia, FSM and PNG; this fleet accounted for a
catch in the range 55,000-80,000 mt annually in the period since 2013. Prior to 2013, the domestic Indonesian
purse-seine fleet accounted for a similar catch level to the Philippines domestic fishery but generally has not fished
in high seas areas. During 2013, the Indonesian fleet catch increased substantially (215,582 mt) with more on-
shore processing facilities and more vessels entering the fishery. However, the purse seine catch in 2015 (~56,000
mt) dropped considerably from this level, mainly due to the introduction of a ban on transhipment-at-sea for vessels
not built in Indonesia (which is nearly all of the current fleet). The Indonesian purse seine catch recovered (214,605
mt in 2017) apparently due to increased catches by the smaller-scale purse seine component of this fleet, although
the provisional 2019 catch was back to 98,734 mt. Prior to 2009, the domestic fleets of Indonesia and Philippines
accounted for about 13-16% of the WCP-CA total purse seine catch, although this proportion has dropped below
10% since then.
Figure 3.2.2 shows annual trends in sets by set type (left) and total tuna catch by set type (right) for the major
purse-seine fleets. Sets on free-swimming (unassociated) schools of tuna dominate during recent years (71% of all
sets for these fleets in 2019). The proportion of sets on drifting FADs in 2019 (25%) was clearly lower than in
2018 (30%), but similar to the recent ten-year average for the major fleets. The number and proportion (2% in
2019) of sets on natural logs was clearly the lowest in the fishery for the major fleets and reflects a move away
from this type of fishing, in line with the improvements in technology/efficiency involving drifting FAD use.
Associated set types, particularly drifting FAD sets, generally account for a higher average catch per set than
unassociated sets, so the percentage of catch for drifting FADs (for 2019 = 36%: Figure 3.2.2right [red]) will be
higher than the percentage of sets for drifting FADs (for 2019 = 25% : Figure 3.2.2left [red]). In contrast, the
catch from unassociated schools in 2019 was 59% of the total catch but taken from 71% of the total sets. Table A3
in the APPENDIX provides a more detailed breakdown of catch and effort by set type in 2000-2019 using available
logsheet and observer data.
7
Figure 3.2.2 Time series showing the percentage of total sets (left) and total catch (right), by school type
for the major purse-seine fleets operating in the WCPCA.
3.3 Environmental conditions
The purse-seine catch/effort distribution in tropical areas of the WCPCA is strongly influenced by El Nino
Southern Oscillation Index (ENSO) events (Figure 3.3.1). Figure 3.4.1 (left) demonstrates the effect of ENSO
events on the spatial distribution of the purse-seine activity, with fishing effort typically expanding further to the
east during El Niño years and contracting to western areas during La Niña periods.
The WCPCA fishery experienced weak-moderate La Niña conditions during 2013, then neutral conditions into
early 2014. El Niño conditions developed during 2014 and strengthened in 2015 to a level not experienced in the
fishery for almost 20 years (i.e. since 1997/1998). El Niño conditions continued into the first half of 2016 but then
abruptly moved to a neutral state by the middle of the year which presided over the fishery into 2017. La Nina
conditions developed in late 2017 and continued into the early months of 2018, before transitioning through a
neutral state which presided over the rest of 2018. Weak-moderate El Nino conditions developed in late 2018,
leading into the middle of 2019, and then subsided later in the year to neutral conditions by the start of 2020. The
current outlook for the remainder of 2020 is a possible move to La Nina conditions by the 3rd-4th quarters 2020.
0%
20%
40%
60%
80%
100%
Other
Drifting FAD
Log
Unassociated
Pacific Islands
0%
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40%
60%
80%
100%
Japan
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100%
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100%
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100%
1980 1984 1988 1992 1996 2000 2004 2008
USA
Percentage of total sets
0%
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40%
60%
80%
100%
1980 1984 1988 1992 1996 2000 2004 2008 2012 2016
Total - main PS fleets
0%
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40%
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80%
100%
Other
Drifting FAD
Log
Unassociated
Pacific Islands
0%
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40%
60%
80%
100%
Japan
0%
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60%
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100%
Korea
0%
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60%
80%
100%
Chinese-Taipei
0%
20%
40%
60%
80%
100%
1980 1984 1988 1992 1996 2000 2004 2008 2012 2016
USA
Percentage of total
0%
20%
40%
60%
80%
100%
1980 1984 1988 1992 1996 2000 2004 2008 2012 2016
Total - main PS fleets
8
Figure 3.3.1 Trends in El Nino Southern Oscillation Index (ENSO), 2005-2020
3.4 Distribution of fishing effort and catch
Despite the FAD closure for certain periods in each year since 2010, drifting FAD sets remain an important fishing
strategy (Figure 3.4.1right), particularly to the east of 160°E. The relatively high proportion of unassociated sets
in the eastern areas (e.g. Gilbert Islands) was a feature of the fishery in 20152016 (i.e. corresponding to El Nino
conditions). The move to ENSO-neutral conditions, then weak La Nina during 2017 into early 2018 resulted in
more effort in the area west of 160°E (Figure 3.4.1bottom left; Figure 3.7.3right) compared to recent years, and
a higher use of drifting FADs in the area east of 160°E (Figure 3.4.1bottom left). By late 2018, weak El Nino
conditions presided over the fishery and relatively high catches were taken in the eastern tropical areas, in and
adjacent to the waters of Tokelau and the Phoenix Group (Figure 3.7.3). El Nino conditions continued into 2019
with purse seine effort extending further to the east compared to recent years (Figure 3.4.1bottom left) and very
good catches were taken in a few concentrated areas of the eastern tropical waters (see Figure 3.7.3).
Figures 3.4.2 through 3.4.6 show the distribution of purse seine effort for the five major purse seine fleets during
2018 and 2019. In general, the distribution of effort for each fleet in 2019 is very similar to 2018 activities, although
some fleets (combined Pacific Island, Korea and USA) extending activities further east in 2019. The US fleet
typically fishes in the more eastern areas and this was again the case during 2018/2019, with effort extended into
the Phoenix and Line Islands, the Cook Islands, Tokelau and the adjacent eastern high seas areas with less effort
west of 160°E. The difference in areas fished by the Asian fleets (Japan, Korean and Chinese Taipei ) in 2018/2019
(Figures 3.4.23.4.5) is related to the areas they have access to and perhaps also related to fishing strategy (e.g.
use of traditional fishing grounds, e.g. FSM, PNG and the Solomon Islands by the Japan fleet). During 2019,
effort by the combined Pacific Islands fleet slightly to the east (e.g. lower proportion of effort in the domestic PNG
fishery) compared to effort during 2018, no doubt related to the prevailing (El Nino) conditions.
Figure 3.4.7 shows the distribution of catch by species for the past seven years, Figure 3.4.8 shows the distribution
of skipjack and yellowfin catch by set type for the same period, and Figure 3.4.9 shows the distribution of estimated
bigeye catch by set type for the past seven years. There are some instances where the composition of the skipjack
catch by set type is clearly different to the composition of the yellowfin catch by set type. Higher proportions of
yellowfin tuna usually occur during El Niño years as fleets have access to “pure” schools of large yellowfin that
are more available in the eastern tropical areas of the WCPCA. In 2019, most of the yellowfin catch in the area
from the Phoenix to the Line Islands was from unassociated sets (Figure 3.4.8right), while associated sets in this
area accounted for most of the skipjack catch (Figure 3.4.8left).
The estimated bigeye catch in the area to the west of 160°E tends to be taken by a mixture of set types, but in
contrast, is dominated by drifting FAD sets in the area to the east of 160°E, which is very clear for 2019 (Figure
3.4.9bottom).
-40
-30
-20
-10
0
10
20
30
JAN
APR
JUL
OCT
JAN
APR
JUL
OCT
JAN
APR
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JAN
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JAN
APR
JUL
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JAN
APR
JUL
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JAN
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APR
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JAN
APR
JUL
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JAN
APR
JUL
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JAN
APR
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JAN
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APR
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JAN
APR
JUL
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JAN
APR
JUL
OCT
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
ENSO Index
ENSO Index
5-month running average
NEUTRAL
LA NINA
EL NINO
9
2013 (+)
2013 (+)
2014 (-)
2014 (-)
2015 (--)
2015 (--)
2016 (-/o)
2016 (-/o)
2017 (o)
2017 (o)
2018 (+/o/-)
2018 (+/o/-)
2019 (-/o)
2019 (-/o)
Figure 3.4.1 Distribution of purse-seine effort (days fishing left; sets by set type right), 20132019.
(BlueUnassociated; YellowLog; RedDrifting FAD; GreenAnchored FAD).
Pink shading represents the extent of average sea surface temperature > 28.5°C
ENSO trends are denoted by “+”: La Niña; “-”: El Niño; “o”: transitional period.
10
Figure 3.4.2 Distribution of effort by Pacific Islands fleets during 2018 and 2019
lines for the equator (0° latitude) and 160°E longitude included.
Figure 3.4.3 Distribution of effort by the Japanese purse seine fleet during 2018 and 2019
lines for the equator (0° latitude) and 160°E longitude included.
Figure 3.4.4 Distribution of effort by the Korean purse seine fleet during 2018 and 2019
lines for the equator (0° latitude) and 160°E longitude included.
Figure 3.4.5 Distribution of effort by the Chinese-Taipei purse seine fleet during 2018 and 2019
lines for the equator (0° latitude) and 160°E longitude included.
Figure 3.4.6 Distribution of effort by the US purse seine fleet during 2018 and 2019
lines for the equator (0° latitude) and 160°E longitude included.
Pacific Is.2018
Pacific Is.2019
Japan2019
Japan2018
Korea2018
Korea2019
Ch. Taipei2018
Ch. Taipei 2019
USA2018
USA2019
11
2013 (+)
2013 (+)
2014 (-)
2014 (-)
2015 (--)
2015 (--)
2016 (-/o)
2016 (-/o)
2017 (o)
2017 (o)
2018 (+/o/-)
2018 (+/o/-)
2019 (-/o)
2019 (-/o)
Figure 3.4.7 Distribution of purse-seine skipjack/yellowfin/bigeye tuna catch (left) and purse-seine
yellowfin/bigeye tuna catch only (right), 20132019
(BlueSkipjack; YellowYellowfin; RedBigeye).
ENSO periods are denoted by “+”: La Niña; “-”: El Niño; “o”: transitional period.
12
2013 (+)
2013 (+)
2014 (-)
2014 (-)
2015 (--)
2015 (--)
2016 (-/o)
2016 (-/o)
2017 (o)
2017 (o)
2018 (+/0/-)
2018 (+/0/-)
2019 (-/o)
2019 (-/o)
Figure 3.4.8 Distribution of skipjack (left) and yellowfin (right) tuna catch by set type, 20132019
(BlueUnassociated; YellowLog; RedDrifting FAD; GreenAnchored FAD).
ENSO periods are denoted by “+”: La Niña; “-”: El Niño; “o”: transitional period.
Sizes of circles for all years are relative for that species only.
13
2013 (+)
2014 (-)
2015 (--)
2016 (-/o)
2017 (o)
2018 (+/0/-)
2011 (++/o/+)
Estimated Bigeye catch
Metric tons
10,000
5,000
1,000
Drifting FAD
Log
Unassociated
Anchored FAD
2019 (-/o)
Figure 3.4.9 Distribution of estimated bigeye tuna catch by set type, 20132019
(BlueUnassociated; YellowLog; RedDrifting FAD; GreenAnchored FAD).
ENSO periods are denoted by “+”: La Niña; “-”: El Niño; “o”: transitional period.
14
3.5 Catch per unit of effort
Figure 3.5.1 shows the annual time series of nominal CPUE by set type and vessel nation for skipjack (left) and
yellowfin (right). These trends are not standardised for factors that may relate to the efficiency of the fleets, e.g.
technological improvements and increased vessel power, so therefore must be interpreted with caution. Recent
reviews of the available logsheet data used to determine nominal CPUE highlight an apparent change in reporting
behaviour, with a clear increase in the reporting of transit days (over days searching); since transit days are not
included as purse seine effort (and days searching is included), this change will inevitably result in a positive bias
in the nominal CPUE data presented herein.
Purse seine skipjack CPUE in 2019 for most fleets was amongst the highest ever, with high catch rates from both
unassociated and drifting FAD sets. It is thought that environmental conditions and strong recruitment were
contributing factors to the recent high catch rates. Over the entire time series, the trend for skipjack CPUE is clearly
increasing, although, as noted, these graphs present nominal CPUE and do not take into account the increase in
fishing efficiency (often referred to as ‘effort creep’). A possible indicator of an increase in fishing efficiency is
the gradual reduction in average trip length over time, which is apparent in the linear trend of VMS trip length,
which is estimated to decrease from 31 days in early 2009 to 27.5 days by mid-2020 (Figure 3.5.3).
Yellowfin purse-seine CPUE shows strong inter-annual variability and there is greater variation in CPUE among
the fleets than for skipjack. School-set yellowfin CPUE appears influenced by ENSO variation in the WCPCA,
with CPUE generally higher during El Niño episodes. This is believed to be related to increased catchability of
yellowfin tuna due to a shallower surface-mixed layer during these periods. Associated (log and drifting FAD) sets
generally yield higher catch rates (mt/day) for skipjack than unassociated sets, while unassociated sets sometimes
yield a higher catch rate for yellowfin than associated sets. The higher yellowfin CPUE from free-schools occurs
when “pure” schools of large, adult yellowfin are more available to the gear in the more eastern areas of the tropical
WCP-CA, and so account for a larger catch (by weight) than the (mostly) juvenile yellowfin encountered in
associated sets.
The purse seine yellowfin CPUE for free-schools in 2019 declined for the fleets typically fishing in the eastern
areas (USA and to some extent Korea) but increased for those fleets with effort concentrated in the west (Japan
and to some extent Chinese Taipei); refer to Figures 3.4.33.4.6. Figure 3.6.2 shows that for unassociated sets the
“pure” schools of large, adult yellowfin were not present in the east during 2019 (compared to 2018), despite the
prevailing El Nino conditions, and no doubt this is the reason for the decline in yellowfin CPUE for free-schools
for the USA fleet, for example.
Yellowfin catch rates on drifting FADs increased slightly for the Korea, US and Chinese Taipei fleets during 2019,
but the CPUE for the Japanese fleet declined; as for CPUE with unassociated sets, this trend is perhaps related to
the respective areas fished. The long-term time series for yellowfin CPUE shows more inter-annual variability and
overall, a flatter trend than the skipjack tuna CPUE. It is unknown whether these trends reflect an increasing ability
to target skipjack tuna at the expense of yellowfin, or reflect a change in yellowfin abundance, given that fishing
efficiency has increased.
The difference in the time of day that sets are undertaken is thought to be one of the main reasons why bigeye tuna
are rarely taken in unassociated schools compared to log and drifting FAD schools, which have catch rates of this
species an order of magnitude higher (Figure 3.5.2). The trends in estimated bigeye tuna CPUE since 2000 varies
by fleet and set type with no clear pattern evident; drifting FADs account for the highest catches and most
variability. The unusually low bigeye catch in 2019 is reflected in the clear declines in CPUE for all fleets (Figure
3.5.2).
Figure 3.5.3 shows the inverse relationship between monthly CPUE (total tuna catch (mt) per day) and average
trip length estimates (from logsheets and VMS); logsheet trip length tends to fluctuate in synchrony with CPUE,
with shorter trips corresponding to higher CPUE. Average trip length (from VMS data) generally compares well
to average trip length (from logsheet data), but as logsheet coverage declines (e.g. early 2019), estimates from
these two sources tend to diverge since available logsheets are probably not representative. The FAD closure
period each year (commencing in 2010) generally coincides with a decline in total tuna CPUE, with longer trips
and apparent difficulties obtaining consistent catches from free-swimming schools. The pattern in high CPUE in
15
the months immediately following the FAD closure periods is understood to be mainly due to the build-up of
unexploited biomass which then becomes available through FADs. The drop in CPUE from late 2016 into the
first 6-8 months of 2017 may simply be due to a return to conditions prior to the most recent El Nino of 2014
2016. For 2019, the total tuna CPUE was at record high levels, even during the mandatory FAD closure months
(JulySeptember). There was a subsequent decline in CPUE in late 2019 and into early 2020, noting that
fluctuations in catch levels are also influenced by economic conditions.
Figure 3.5.1 Skipjack tuna CPUE (mt per dayleft) and yellowfin tuna CPUE (mt per dayright) by set-
type, and all set types combined, for selected purse-seine fleets fishing in the tropical WCPCA.
Effort and CPUE were partitioned by set type according to the proportions of total sets attributed to each set type.
Thick black line for “All set types” represents the Pacific Islands purse seine fleets combined.
0
10
20
30
40
50
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Free-school
0
5
10
15
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Free-school
0
10
20
30
40
50
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Log
0
5
10
15
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Log
0
10
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1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Drifting FAD
0
5
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1988 1992 1996 2000 2004 2008 2012 2016
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Drifting FAD
0
10
20
30
40
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1988 1992 1996 2000 2004 2008 2012 2016
CPUE
All set types
JAPAN
KOREA
Chinese Taipei
USA
PACIFIC Is.
0
5
10
15
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
All set types
16
Figure 3.5.2 Estimated bigeye tuna CPUE (mt per day) by major set-type categories (free-school, log and
drifting FAD sets) and all set types combined for Japanese, Korean, Chinese-Taipei and US purse seiners
fishing in the tropical WCPCA.
Effort and CPUE were partitioned by set type according to the proportions of total sets attributed to each set type.
Thick black line for “All set types” represents the Pacific Islands purse seine fleets combined.
Figure 3.5.3 Monthly purse-seine tuna CPUE (mt/day) and average trip length (VMS days), 20052020
Dashed, black line represents the linear trend on VMS Trip length. VMS Trip length axis (right) is inverted.
For 2019, only the full-fishery, mandatory FAD closure period (July-Sept) is shown and acknowledges that flag states must choose an
additional two-month FAD closure period as per the requirements in CMM 2018-01 para. 17.
3.6 Species/Size composition of the catch
Figures 3.6.1 and 3.6.2 show the species and size composition of the purse seine catch for 2018 and 2019, by set
type and broad area of the tropical fishery. Points of interest in the comparison of these graphs include:
- A broader range of skipjack tuna (to 75 cm) in the area east of 170°E from unassociated sets in 2018
compared with 2019, but also compared to the associated sets in 2019 for the same area;
- A higher proportion of the bigeye tuna in associated sets east of 170°E than in the west;
- The absence of large yellowfin tuna in the unassociated set catch in the area east of 170°E in 2019
compared to 2018.
0
1
2
3
4
5
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Free-school
0
1
2
3
4
5
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Log
0
1
2
3
4
5
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
Drifting FAD
0
1
2
3
4
5
1988 1992 1996 2000 2004 2008 2012 2016
CPUE
All set types
JAPAN
KOREA
Chinese Taipei
USA
PACIFIC Is.
10
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30
35
40
4510
20
30
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60
2009-1
2009-7
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2014-7
2015-1
2015-7
2016-1
2016-7
2017-1
2017-7
2018-1
2018-7
2019-1
2019-7
2020-1
2020-7
Trip Length (Days)
TUNA CPUE (MT/Day)
LOGSHEET TUNA CPUE (Left axis)
VMS Trip Length (Right axis)
FAD Closure periods
17
Figure 3.6.1 Species composition (MT: Y-axis) of the 2018 and 2019 purse seine catch, by set type and 5cm
size categories (X-Axis) for the tropical fishery, west of 170°E.
Skipjack tunablue; Yellowfin tunayellow; Bigeye tunared
Figure 3.6.2 Species composition (MT: Y-axis) of the 2018 and 2019 purse seine catch, by set type and 5cm
size categories (X-Axis) for the tropical fishery, east of 170°E.
Skipjack tunablue; Yellowfin tunayellow; Bigeye tunared
Bottom graph shows the catch volume by year, species and set type
Source : observer data
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
105
110
115
120
125
130
135
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145
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155
160
2018 - Unassociated
20
25
30
35
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45
50
55
60
65
70
75
80
85
90
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2019 - Unassociated
20
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2018 - Associated
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2019 - Associated
0
100,000
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2018 - Unassociated 2019 - Unassociated 2018 - Associated 2019 - Associated
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2018 - Unassociated
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2019 - Unassociated
20
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2018 - Associated
20
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2019 - Associated
0
100,000
200,000
300,000
400,000
500,000
600,000
2018 - Unassociated 2019 - Unassociated 2018 - Associated 2019 - Associated
18
3.7 Seasonality
Figures 3.7.1 and 3.7.2 show the seasonal average CPUE for skipjack and yellowfin tuna in the purse seine fishery
for the period 20142019, respectively. Figure 3.7.3 shows the distribution of effort by quarter for the period 2014-
2018 in comparison to effort by quarter in 2019. Prior to implementation of the FAD closure, the average monthly
skipjack CPUE was generally highest in the first half of the year and slightly lower thereafter, which is in contrast
to the yellowfin CPUE, which was at its lowest during the first six months, but higher thereafter. This situation
corresponds to the seasonal eastwards extension of the fishery in the second half of the year, to an area where
schools of large yellowfin are thought to be more available than areas to the west due to, inter alia, a shallower
surface-mixed layer. The FAD closure implementation since 2009 has tended to reduce CPUE during those [FAD-
closure] months, with relatively high catch rates experienced immediately following the last FAD-closure month.
The trend in monthly skipjack CPUE for 2019 was above the 2014-2018 monthly average for all months JanOct,
with the highest monthly CPUE for the past six years in the months of Feb and AprOct, with NovDec as the
only months below this average. High skipjack catches in the period to Apr-Oct were concentrated in the Gilbert
Islands, Tuvalu, Nauru and adjacent high seas (Figure 3.7.3).
The quarterly extent of the warm pool (i.e. surface water >28.5°C on average) in 2019 compared to the average
for 2014-2018 (Figure 3.7.3) shows that the El Nino conditions in early 2019 extended the warm pool and the
fishery further east than the recent 5-year average (20142018). The monthly yellowfin CPUE for 2019 was higher
than the 20142018 average in the 1st quarter of 2019, with good yellowfin tuna catches in PNG and the area from
Phoenix to the Line Islands (Figures 3.7.2 and 3.7.3). The monthly yellowfin CPUE for 2019 was at the 2014
2018 monthly average for the 2nd quarter, but from July onwards, slightly lower that this recent 5-year average.
Figure 3.7.1 Average monthly skipjack tuna CPUE (mt per day) for purse seiners fishing in the tropical
WCPCA, 20142019.
Red line represents the period 20142018 and the blue line represents 2019.
The bars represent the range (i.e. minimum and maximum) of monthly values for the period 20142018.
Figure 3.7.2 Average monthly yellowfin tuna CPUE (mt per day) for purse seiners fishing in the tropical
WCPCA, 20142019.
Red line represents the period 20142018 and the blue line represents 2019.
The bars represent the range (i.e. minimum and maximum) of monthly values for the period 20142018.
0
5
10
15
20
25
30
35
40
45
50
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
CPUE
2014-2018
2019
0
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4
6
8
10
12
14
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
CPUE
2014-2018
2019
19
1st Quarte r
1st Quarte r
2nd Quarte r
2nd Quarte r
3rd Quarter
3rd Quarter
4th Quarte r
4th Quarte r
Figure 3.7.3 Quarterly distribution of purse-seine catch by species for 20142018 (left) and 2019 (right).
(BlueSkipjack; YellowYellowfin; RedBigeye)
Pink shading represents the extent of average sea surface temperature >28.5°C by quarter for the period 20142018 (left) and 2019 (right)
20
3.8 Prices, catch value and overall economic conditions
3.8.1 Prices
Skipjack
Following their recent peak in 2017 global skipjack prices have been on a downward trend. In 2019 the price of
Thai imports (c&f) fell 15% to average $1,399/mt while Yaizu purse seine caught skipjack prices (ex-vessel) fell
12% to average ¥144/kg ($1,321/mt). In real terms (that is, adjusting for inflation
4
) 2019 Thai import and Yaizu
purse seine caught USD skipjack prices were 6% and 15% lower than their 20-year averages respectively. Over
the period January to May in 2020, Thai import purse seine caught skipjack prices average $1,228/mt while Yaizu
prices averaged around ¥169/kg ($1,556/mt). Bangkok market reports indicate that skipjack prices (4-7.5lbs, c&f)
increased significant between late 2019 and the end the first Quarter of 2020, rising from $900/mt in November
2019 to $1,500 in March 2020, before declining again to be $1,200/mt at the end of June. The Bangkok skipjack
(4-7.5lbs, c&f) price index over the year to May in 2020 is currently marginally above that of the FAO Food Price
Index which has been relatively steady since 2015 (Figure 3.8.2). In addition, over the period to May in 2020 Thai
import volumes were down by around 28% compared with 2019 with this decline reportedly driven by low catch
rates in the early part of the year.
Yellowfin
In 2019 the Thai import prices (c&f) for yellowfin
averaged $1,925/mt, down by 2% from the previous
year levels while Yaizu purse seine caught yellowfin
prices (ex-vessel) declined 9% to ¥255/kg ($2,338/mt).
In real terms the Thai import prices were only 3%
higher in 2019 than the 20 year average while 2019
Yaizu real prices was below their 20 year average by
8%.
Prices over the period to the end of May 2020 are below
the levels seen in 2019 with Thai import prices
averaging $1,605/mt and Yaizu prices averaging
¥227/kg ($2,092/mt). In addition, over the period to
May in 2020 Thai import volumes were down by around 20% compared with 2019.
4
Based on the US CPI as measured by the Bureau of Labor Statistics All Urban Consumers CPI (www.bls.gov/cpi/data.htm)
Figure 3.8.1 Annual skipjack prices, Thai
imports (c&f) and Yaizu (ex-vessel)
Note: *For the period January to May
0
500
1000
1500
2000
2500
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020*
$ per metric tonne
Yaizu
Thai imports
Figure 3.8.2 FAO Food Price Index and
Bangkok 4-7.5lbs skipjack price (c&f) index
Note: *For the period January to June
-
20
40
60
80
100
120
140
160
180
1990
1991
1992
1993
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2001
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2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020*
Price Index (2014-2016 average =100)
FAO Food Price Index
Bangkok Skipjack Price Index
Figure 3.8.3 Annual yellowfin prices, Thai
imports (c&f) and Yaizu (ex-vessel)
Note: *For the period January to May
-
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
4,500
1997
1998
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2000
2001
2002
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2004
2005
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2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
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2018
2019
2020*
$ per metric tonne
Yaizu
Thai imports
21
3.8.2 Catch Value
The purse seine tuna catch in the WCP-
CA area for 2019 is estimated to be
valued at $3.02 billion, a decline of $206
million (6%) from 2018.
5
This
represents the 6th highest purse seine
catch value level on record in nominal
terms since 1997. The decline in
nominal value in 2019 was driven by a
significant decline in the value of the
yellowfin, skipjack and bigeye catch of
$113 million (15%), $66 million (3%)
and $28 million (26%) respectively
from the previous year.
The decline in the value of the skipjack
catch in 2019 to $2.31 billion (76% of
the total purse seine tuna catch value)
was largely driven by lower prices. Similarly, the decline in yellowfin prices saw the value of the yellowfin catch
declined to $635 million which represemnts 21% of the total value of the purse seine catch. Bigeye contributed
$79 million or 3% of the total value of the purse seine catch in 2019.
3.8.3 Economic Conditions in the tropical purse seine fishery
Economic conditions indexes for the major WCPFC-CA tuna fisheries has been presented to SC for a number of
years. These indexes assess economic conditions in a fishery based on relative fish price, fishing cost (excluding
license and access fee payments) and catch rates over the past 20 years (that is, 1999-2018). Together, information
from the three components are combined into a single value expressed as an index against the average value over
the preceding 20 years, set to 100, and provide a relative measure of changes in economic conditions over time.
Values below 100 suggest that the fishery is experiencing below average economic conditions, while values of
over 100 show periods in which economic conditions in the fishery are relatively favourable.
6
It is important to
note that the indexes relate to the fishery not the vessels operating within it and, as such, while favourable economic
conditions may be indicative of the ability of the fishery to generate significant profits they do not indicate which
parties, e.g. vessel owners or coastal states, these profits accrue to.
Despite the falls in prices and increases in fuel costs, a surge in catch rates saw the continuation of good economic
conditions in the purse fishery with the tropical purse seine fishery
7
economic conditions index remaining
significantly above the 20-year average. Since 2012, the index has consistently outperformed the 20-year average
index, however, in 2014 as fish prices declined, the index returned to more average levels. In the recent years,
there is considerable variation in the contribution of the different index components. For instance, in 2012, 2013
and 2017, the high index readings were driven primarily by high fish prices while high catch rates were the main
driver between 2014 and 2016 and in 2018 and 2019. The continuation of the decline in fish prices saw the
economic conditions in 2019 decline marginally from 2018 levels despite the higher catch rates and lower fuel
prices.
5
The delivered value of each year’s catch is estimated as the sum of the product of the annual purse catch of each species, excluding the
Japanese purse seine fleet’s catch, and the average annual Thai import price for each species (bigeye was assumed to attract the same price
as for skipjack) plus the product of the Japanese purse seine fleet’s catch and the average Yaizu price for purse seine caught fish by species.
Thai import and Yaizu market prices were used as they best reflect the actual average price across all fish sizes as opposed to prices provided
in market reports which are based on benchmark prices, for example, for skipjack the benchmark price is for fish of size 4-7.5lbs. In deriving
these estimates certain assumptions were made due to data and other constraints that may or may not be valid and as such caution is urged
in the use of these figures.
6
Full details of the methodology used to derive the economic conditions indexes presented can be found in Skirtun, M and Reid, C. 2018,
Analyses and projections for economic condition in WCPO fisheries, WCPFC-SC14-2018 ST- IP-06, Busan, Republic of Korea, August
8-16.
7
The tropical purse seine fishery economic conditions index is based on the fishery that lies between 10⁰N and 10⁰S of the WPCFC-CA,
excluding the waters of Indonesia, Philippines and Vietnam.
Figure 3.8.4 Value of the WCPFC-CA purse seine fishery
tuna catch by species
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0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
1997
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2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
$ billion
Skipjack
Yellowfin
Bigeye
Albacore
22
Figure 3.8.5 Tropical purse seine fishery economic conditions component indexes
Figure 3.8.6 Tropical purse seine fishery economic conditions index (LHS) and variance of component
indices against average (2000-2019) conditions (RHS)
40
60
80
100
120
140
160
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
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2014
2015
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2017
2018
2019
Index (average 2000-2019 = 100)
Price Index
60
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160
2000
2001
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2003
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2005
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2010
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2018
2019
Index (average 2000-2019 = 100)
Cost Index
60
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160
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2001
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2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
Index (average 2000-2019 = 100)
CPUE index
-60
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-20
0
20
40
60