Eastern Tuna and Billfish Fishery

Area fished, fishing methods and key species

The Eastern Tuna and Billfish Fishery (ETBF) operates in the Exclusive Economic Zone and adjacent high seas, from Cape York to the Victoria – South Australia border, including waters around Tasmania and the high seas of the Pacific Ocean (Figure 21.1). Domestic management arrangements for the ETBF are consistent with Australia's commitments to the Western and Central Pacific Fisheries Commission (WCPFC; see Chapter 20).

Key species in the ETBF are shown in Table 21.1. Most of the catch in the fishery is taken with pelagic longlines, although a small quantity is taken using minor-line methods (Table 21.2). Some ETBF longliners catch southern bluefin tuna (Thunnus maccoyii) off New South Wales during winter, after fishing for tropical tunas and billfish earlier in the year, while others take them incidentally when targeting other tunas. All southern bluefin tuna taken must be covered by quota and landed in accordance with the Southern Bluefin Tuna Fishery Management Plan 1995. Recreational anglers and game fishers also target tuna and marlin in the ETBF. Many game fishers tag and release their catch, especially marlins. The retention of blue marlin (Makaira mazara) and black marlin (M. indica) has been banned in commercial fisheries since 1998, and catch limits have been introduced on longtail tuna (T. tonggol), in recognition of the importance of these species to recreational anglers.

Management methods

The primary ETBF tuna and billfish species are managed through total allowable catches allocated as individual transferable quotas (ITQs). The Commonwealth Fisheries Harvest Strategy Policy (HSP; Department of Agriculture and Water Resources 2018) is not prescribed for fisheries managed under international agreements. However, a harvest strategy framework was developed for the ETBF (Campbell 2012) to set the total allowable commercial catch (TACC) for the 5 main species. For reasons set out below, this harvest strategy framework has been discontinued for the 3 tuna species, and is being redeveloped for swordfish (Xiphias gladius) and striped marlin (Kajikia audax).

Australia's annual catch of albacore (T. alalunga), bigeye tuna (T. obesus) and yellowfin tuna (T. albacares) in the ETBF represents only a small percentage of the total catch from all nations in the Coral and Tasman seas (averaging 6%, 16% and 27%, respectively, since 2006) (Campbell 2019a). Consequently, in 2013, the Tropical Tuna and Billfish Fisheries Resource Assessment Group (TTRAG) concluded that the ETBF harvest strategy was not likely to achieve its objectives (including achieving the target catch rate) because changes to Australia's catch would not likely lead to significant changes to stock levels. As a result, harvest strategies are not used to calculate recommended biological commercial catch levels for albacore tuna, bigeye tuna and yellowfin tuna (Campbell 2019b). In the absence of an accepted domestic harvest strategy, and noting that WCPFC harvest strategies for these species are still under development and the WCPFC has not yet allocated tuna catches, AFMA considered a range of other factors in applying TACCs.

Australia's annual catch of swordfish and striped marlin in the ETBF represents more than half the total catch from all nations in the Coral and Tasman seas (averaging 67% and 56%, respectively, since 2006) (Campbell 2019a), so changes in Australia's catch of these species could result in a change in stock levels. As such, under a project with CSIRO through the TTRAG, the Australian Fisheries Management Authority (AFMA) is redeveloping harvest strategies for swordfish and striped marlin. The swordfish harvest strategy was approved by the TTRAG and the Tropical Tuna Management Advisory Committee and subsequently adopted by the AFMA Commission at its 73rd meeting in September 2020. Development of the striped marlin harvest strategy continues and is expected be finalised in 2021.

The status of ETBF tuna and billfish is derived from regional assessments undertaken for the WCPFC. Assessment results over the relevant geographic area modelled are used to determine stock status, but supplementary management advice may also be derived from the region most relevant to Australia. The WCPFC has agreed limit reference points for some stocks (albacore, bigeye tuna and yellowfin tuna), but, where agreed limit reference points are absent (swordfish and striped marlin), status determination was informed by the proxies specified in the HSP.

Fishing activity

The number of active vessels in the fishery (Figure 21.2) has decreased substantially in the past 2 decades (from around 152 in 1999 to 35 in 2020), probably as a result of a decline in economic conditions in the fishery Similarly, the effort in hooks set has declined (though to a lesser extent) from a peak of more than 12 million in 2003 to around 8 million per year in recent years (Figure 21.2).

Note: SFR Statutory fishing right.
Source: AFMA

Following a decrease in effort from 2003, the total retained catch of all species in the ETBF declined from a high of more than 8,000 t in 2002 to around 4,200 t in 2013. Catch decreased from 4,341 t in 2019 to 3,945 t in 2020 (Figure 21.3). Swordfish, yellowfin tuna and bigeye tuna continue to be the main target species.

Source: AFMA

Table 21.2 Main features and statistics for the ETBF

Fishery statistics a	2019			2020
Stock	TACC (t)	Catch (t)	GVP (2018–19)	TACC (t)	Catch (t)	GVP (2019–20)
Striped marlin	351	251	$0.9 million	351	186	$1.1 million
Swordfish	1,250	793	$7.3 million	1,250	539	$6.7 million
Albacore	2,500	924	$2.7 million	2,500	1,160	$3.3 million
Bigeye tuna	1,056	284	$4.6 million	1,056	303	$3.0 million
Yellowfin tuna	2,400	2,089	$14.7 million	2,400	1,757	$24.4 million
Total fishery	7,557	4,341	$32.1 million	7,557	3,945	$39.8 million
Fishery-level statistics
Effort	Longline: 8.56 million hooks Minor line: 0			Longline: 8.12 million hooks Minor line: 0
Fishing permits	Longline boat SFRs: 81 Minor-line boat SFRs: 84			Longline boat SFRs: 81 Minor-line boat SFRs: 83
Active vessels	Longline: 37 Minor line: 0			Longline: 35 Minor line: 0
Observer coverage	Longline: 11.7% b Minor line: 0			Longline: 9.7% b Minor line: 0
Fishing methods	Pelagic longline, minor line (trolling, rod and reel, handline)
Primary landing ports	Bermagui, Coffs Harbour and Ulladulla (New South Wales); Cairns, Mooloolaba and Southport (Queensland)
Management methods	Output controls: TACCs and ITQs Input controls: limited entry, gear restrictions
Primary markets	Domestic: fresh International: Japan, United States – mainly fresh; Europe – frozen; American Samoa, Indonesia, Thailand – albacore mainly for canning
Management plan	Eastern Tuna and Billfish Fishery Management Plan 2010

a Fishery statistics are provided by calendar year to align with international reporting requirements. As of 2019, season and calendar year are the same. Value statistics are by financial year. Total value includes value from non-quota species caught in the ETBF. b From 1 July 2015, electronic monitoring became mandatory for all full-time pelagic longline vessels in the ETBF. At least 10% of video footage of all hauls is reviewed to verify the accuracy of logbooks, which must be completed for 100% of shots. The percentage of hooks observed is provided. Onboard observers are no longer used.
Notes: GVP Gross value of production. ITQ Individual transferable quota. SFR Statutory fishing right. TACC Total allowable commercial catch.

Striped marlin (Kajikia audax)

Line drawing: FAO

Stock structure

Genetic studies have identified multiple stocks of striped marlin in the Pacific Ocean (for example, McDowell & Graves 2008; Purcell & Edmands 2011). As a result, the north Pacific Ocean and south-west Pacific Ocean (SWPO) stocks are assessed separately (WCPFC 2013). Information for the SWPO stock is reported here.

Catch history

Striped marlin catch in the ETBF decreased in 2020 to 186 t (Figure 21.4), while catch in the WCPFC (south of the equator) increased slightly from 1,041 t in 2018 to 1,085 t in 2019 (Figure 21.5).

Note: TACC Total allowable commercial catch. TACC in 2018 was adjusted for a 10-month season.
Source: AFMA

Source: WCPFC

Stock assessment

The last stock assessment for striped marlin in the SWPO (0–40°S, 140°E to 130°W) was in 2019 (Ducharme-Barth, Pilling & Hampton 2019). Influential changes from the previous (2012) assessment included use of standardised catch-per-unit-effort for the Japanese and Chinese Taipei fisheries, calculated using a geostatistical model, and updating the biological information on maturity and defining maturation as a function of length rather than age. The full stock assessment comprises a grid of 300 individual assessment models covering 6 axes of uncertainty, all with equal weighting.

The grid median recent spawning stock biomass (SB) was 19.8% (80% probability interval [PI] 9–46%) of the levels predicted to occur in the absence of fishing. There was a 50.3% probability that the recent spawning stock biomass had breached the Commonwealth default limit reference point (0.2SB₀). This was more pessimistic than the previous (2012) assessment in which spawning biomass (2006 to 2009) was estimated to be 34% of the levels predicted to occur in the absence of fishing.

In terms of maximum sustainable yield (MSY), the median recent spawning biomass was clearly below the level associated with MSY (SB_recent/SB_MSY = 74%; 80% PI 33–163%). There was a 68.6% probability that the recent spawning biomass depletion was below the spawning biomass associated with MSY.

The median recent fishing mortality was below the level associated with MSY (F_recent/F_MSY = 91%; 80% PI 31–189%). There was a 44.3% probability that the recent fishing mortality was above F_MSY. This is slightly more pessimistic than the previous (2012) assessment, where fishing mortality was at 81% of the level associated with MSY.

Stock status determination

The most recent median estimate of the SWPO spawning biomass of striped marlin is estimated to be very close to, but just below, the 0.2SB₀ limit reference point adopted in the HSP and in the WCPFC for tunas (specifically, 20% of the levels predicted to occur in the absence of fishing). As a result, the striped marlin stock in the SWPO (including the ETBF) is classified as overfished. The most recent median estimate of fishing mortality (and a majority of the grid outcomes) was below the level associated with MSY (F_MSY). As a result, the stock is classified as not subject to overfishing. The WCPFC Scientific Committee recommended measures to control overall catch, through expansion of the geographical scope of CMM 2006-04 to cover the distribution of the stock; the WCPFC has not yet adopted this recommendation.

Swordfish (Xiphias gladius)

Line drawing: Gavin Ryan

Stock structure

Although studies of swordfish have generally indicated a low level of genetic variation in the Pacific Ocean (Kasapidis et al. 2008), the WCPFC assesses 2 stocks separately: a north Pacific stock and an SWPO stock. The information reported here is for the SWPO stock (0–50°S, 140°E to 130°W).

Catch history

Swordfish catch in the ETBF decreased in 2020 to 539 t (Figure 21.6). Catch in the south Pacific has been decreasing since 2015, and decreased slightly in 2019 to 6,057 t (Figure 21.7).

Note: TACC Total allowable commercial catch. TACC in 2018 was adjusted for a 10-month season.
Source: AFMA

Source: WCPFC

Stock assessment

The SWPO stock of swordfish was most recently assessed in 2017 using the assessment package MULTIFAN-CL (Takeuchi, Pilling & Hampton 2017). The stock assessment was based on a structural uncertainty grid that included steepness, size data weighting, diffusion rate and natural mortality as the main uncertainties. The uncertainty grid using this approach contained 72 related models. The WCPFC Scientific Committee agreed to use the full grid, with equal weighting for all axes of uncertainty. Note that the primary uncertainty in the 2013 assessment (Davies et al. 2013), relating to growth and maturity schedules, has been resolved based on new research (Farley et al. 2016).

Across all models in the uncertainty grid, the spawning biomass declined steeply between the late 1990s and 2010, but the rate of decline has been less since then. These declines are greater in eastern region 2 (equator to 50°S, 165°E to 130°W), where fishing mortality is also greater, compared with western region 1 where the Australian fishery operates.

The median recent spawning stock biomass was 35% (80% PI 29–43%) of the levels predicted to occur in the absence of fishing. The probability that the recent spawning stock biomass has breached the limit reference point was very low. The median recent fishing mortality was below the level of fishing mortality associated with MSY (F_recent/F_MSY = 86%; 80% PI 51–123%). The probability that the recent fishing mortality was above F_MSY was about 32%.

Stock status determination

Based on the uncertainty grid, the spawning biomass is highly likely above the limit reference point of 0.2SB_F=0 adopted for tunas (noting that the WCPFC Commission has yet to adopt a limit reference point for this stock). As a result, the swordfish stock in the SWPO (including the ETBF) is classified as not overfished.

Recent fishing mortality is also likely below F_MSY. The stock is therefore classified as not subject to overfishing.

Albacore (Thunnus alalunga)

Line drawing: FAO

Stock structure

Two distinct stocks of albacore (north Pacific and south Pacific) are found in the Pacific Ocean, generally associated with the 2 oceanic gyres. These 2 stocks are assessed separately (WCPFC 2015). Information for the south Pacific albacore stock (0–50°S, 140°E to 130°W) is reported here.

Catch history

Albacore catches in the ETBF increased slightly to 1,160 t in 2020 (Figure 21.8). Catches in the south Pacific have been somewhat variable over the past decade, in the range 66,000 t to 93,000 t, with 85,050 t taken in 2019 (Figure 21.9). The WCPFC Scientific Committee recommended that longline fishing mortality be reduced if the WCPFC goal is to maintain economically viable catch rates; WCPFC adopted a target reference point to achieve this goal (0.56SB₀) in 2018.

Note: TACC Total allowable commercial catch. TACC in 2018 was adjusted for a 10-month season.
Source: AFMA

Source: WCPFC

Stock assessment

The assessment for albacore in the south Pacific was updated in 2018 using MULTIFAN-CL (Tremblay-Boyer et al. 2018). Significant improvements in the 2018 stock assessment included modifications to the catch rate index of abundance, inclusion of a higher natural mortality (0.4) in the grid, inclusion of alternative growth models and a simplified regional structure. These changes resulted in more optimistic outcomes than the 2015 assessment. The WCPFC Scientific Committee provided advice based on the full set of 72 models in the uncertainty grid, with equal weighting for all axes of uncertainty.

The median recent spawning stock biomass was 52% (80% PI 37–63%) of the levels predicted to occur in the absence of fishing. The probability that the recent spawning stock biomass had breached the limit reference point was zero. The median recent fishing mortality was below the level associated with MSY (F_recent/F_MSY = 20%; 80% PI 8–41%). The probability that the recent fishing mortality was above F_MSY was zero.

Stock status determination

The most recent estimate of spawning biomass is very likely above the default limit reference point of 20% of initial unfished levels. The most recent estimates of fishing mortality are very likely below the levels associated with MSY, and recent catches are around MSY. As a result, albacore in the south Pacific Ocean (including the ETBF) is classified as not subject to overfishing and not overfished.

Bigeye tuna (Thunnus obesus)

Line drawing: FAO

Stock structure

Genetic data have indicated that bigeye tuna in the Pacific Ocean is a single biological stock (Grewe & Hampton 1998).

Catch history

Bigeye tuna catch increased in the ETBF to 303 t in 2020 (Figure 21.10), but this was the second lowest catch since 1996. Catches decreased in the WCPFC area in 2019 (Figure 21.11). Recent bigeye tuna catch in the WCPFC area (135,442 t in 2019) is below the estimated MSY (median 140,720 t). Catches have generally been above this MSY level over the past decade (Figure 21.11).

Note: TACC Total allowable commercial catch. TACC in 2018 was adjusted for a 10-month season.
Source: AFMA

Source: WCPFC

Stock assessment

The bigeye tuna stock in the western and central Pacific Ocean (WCPO) was most recently assessed in 2020 (Ducharme-Barth et al. 2020) using the assessment package MULTIFAN-CL. The stock assessment is based on a structural uncertainty grid that includes steepness, growth, maturity, tagging dispersion, size data weighting and regional structure as the main uncertainties. The uncertainty grid using this approach contained 24 related models.

The median recent spawning biomass was 41% (80% PI 27–52%) of the levels predicted to occur in the absence of fishing. There was zero probability that the recent spawning stock biomass had breached the limit reference point. The median recent fishing mortality was below the level associated with MSY (F_recent/F_MSY = 72%; 80% PI 49–102%). There was a 12.5% probability that the recent fishing mortality was above F_MSY.

Significant concerns and problems were found with the most recent assessment and modelling approach (Ducharme-Barth et al. 2020) and the bigeye tuna assessment will be independently reviewed during 2021–22.

Stock status determination

Based on the uncertainty grid, the spawning biomass is very likely to be above the limit reference point of 20%SB_F=0 adopted for tunas. As a result, the stock is classified as not overfished. Similarly, recent fishing mortality is very likely to be below F_MSY. As a result, the WCPO stock (including the ETBF) is classified as not subject to overfishing.

Yellowfin tuna (Thunnus albacares)

Line drawing: FAO

Stock structure

Yellowfin tuna in the WCPO is currently considered to be a single biological stock (Langley, Herrera & Million 2012). However, a recent study using newer genomic techniques provided strong evidence of genetically distinct populations of yellowfin tuna at 3 sites (Coral Sea, Tokelau and California) across the Pacific Ocean (Grewe et al. 2015). Further work is underway to confirm and expand on this preliminary study.

Catch history

Yellowfin tuna catch decreased slightly in the ETBF in 2020 to 1,757 t (Figure 21.12). In the wider WCPFC area catches have increased progressively, and have risen 6-fold since 1970 to 696,797 t in 2019 (Figure 21.13), which is below the estimated MSY (median 1,091,200 t).

Note: TACC Total allowable commercial catch. TACC in 2018 was adjusted for a 10-month season.
Source: AFMA

Source: WCPFC

Stock assessment

The yellowfin tuna stock in the WCPO was most recently assessed in 2020 (Vincent et al. 2020) using the assessment package MULTIFAN-CL. The stock assessment is based on a structural uncertainty grid that includes steepness, tagging dispersion, tag mixing, size frequency and regional structure as the main uncertainties. The uncertainty grid using this approach contained 72 related models. The WCPFC Scientific Committee agreed to use the full grid, with equal weighting for all axes of uncertainty.

The median recent spawning stock biomass was 58% (80% PI 51–64%) of the levels predicted to occur in the absence of fishing. The probability that the recent spawning stock biomass had breached the limit reference point was zero. The median recent fishing mortality was below the level associated with MSY (F_recent/F_MSY = 36%; 80% PI 27–47%). The probability that the recent fishing mortality was above F_MSY was zero.

Significant concerns and problems were found with the most recent assessment and modelling approach (Vincent et al. 2020) and the yellowfin tuna assessment will be independently reviewed during 2021–22.

Stock status determination

Based on the uncertainty grid, the spawning biomass is very likely to be above the limit reference point of 0.2SB_F=0 adopted for tunas. As a result, the WCPFC stock (including the ETBF) is classified as not overfished. Similarly, recent fishing mortality is highly likely to be below F_MSY. As a result, the stock is classified as not subject to overfishing.

Key economic trends

Key economic trends

The ETBF's gross value of production (GVP) has fluctuated around $35 million per year over the past 10 years and has corresponded largely with yellowfin tuna GVP (Figure 21.14). The fishery's GVP peaked at $52.1 million in 2015–16, reflecting increased catch of all key targeted species and generally improved prices that year.

Note: GVP Gross value of production. ‘Real’ indicates that value has been adjusted for inflation.

ABARES has conducted economic surveys of the ETBF since the early 1990s to estimate the net economic returns (NER) earned in the fishery. Survey results are available for the 2015–16 and 2016–17 financial years, and preliminary non-survey-based estimates are available for the 2017–18 and 2018–19 financial years. NER have demonstrated a persistent long-term positive trend since 2002–03 (Mobsby et al. 2021) and peaked at $9.6 million in 2015–16 (Figure 21.15). The rise in NER from 2002–03 to 2016–17 was driven largely by improvements in fleet productivity, in an environment of declining output prices and rising input prices. In 2017–18 and 2018–19 NER will likely trend lower, largely as a result of a lower contribution from yellowfin tuna to fishing revenues, and lower GVP overall.

Improved productivity of the ETBF fleet between 2002−03 and 2016−17, as indicated by total factor productivity analysis by Mobsby et al. (2021), has positively affected the fishery's long-term economic performance (Figure 21.15). A possible driver of this improved productivity was the reduction in fleet size (and exit of less-efficient vessels) from 138 to 41 active vessels. Since 2016–17, fleet size has continued to decrease: the remaining 2 active minor-line vessels exited the ETBF in 2017–18 and there were 35 active longline vessels in 2019–20.

Notes: NER Net economic returns.
Source: Mobsby et al. 2021

Management costs as a share of GVP decreased from 11% to 4% between 2005−06 and 2016−17 (Mobsby et al. 2021). Reduced management costs linked to increasing productivity and NER indicate increasing efficiency and effectiveness in the fishery's management of expenditure.

Performance against economic objective

Estimates of maximum economic yield are not available for this fishery. However, stock levels for the main commercial tuna species caught in the ETBF – yellowfin tuna, albacore and bigeye tuna – are relatively high at 58%, 52% and 41%, respectively, of the levels expected in the absence of fishing. These healthy stock levels generally lower the cost of fishing and improve NER.

The significant reduction in fleet size and the shift to ITQs has likely resulted in more productive and profitable operators remaining in the fishery. This is consistent with the increasing trend in effort levels per boat (based on number of hooks used per longline vessel) and increasing total factor productivity. ITQs allow fishers to determine the best combination of inputs to minimise costs and maximise revenue for a given level of catch. ITQs also contribute to improved fishery-level productivity and profitability by providing for autonomous adjustment as the most productive and profitable operators acquire quota.

Given the relatively stable key fish stock levels over the past 2 decades, positive trends in productivity and NER indicate that resource rents from the ETBF are being realised and not dissipated through overcapitalisation or overfishing of the fish stock.

Product from the ETBF is included on the List of Exempt Native Specimens under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and has export approval until 19 August 2022. Conditions under this approval, in addition to standard conditions of reporting and monitoring, include updating the ecological risk assessment (ERA) for the ETBF, developing and implementing a framework for the management of non-quota and bycatch species, and continuing to determine the impact of fishing in the ETBF on shark species.

The most recent ERA for the ETBF was finalised in 2019 (Sporcic et al. 2018). Of 261 species evaluated at ERA level 2, 8 species were found to be at potential high risk after productivity susceptibility analysis or sustainability assessment for fishing effects. The subsequent residual risk analysis, examining logbook and observer data, demonstrated that there was a low or zero level of reported interactions and/or higher survivability than assumed in the initial analyses, reducing the risk posed by the fishery to these species to medium or low. There was no requirement to progress to a level 3 analysis in the most recent ERA.

In accordance with accreditation under the EPBC Act (see Chapter 1, 'Protected species interactions'), AFMA publishes and reports quarterly on interactions with protected species on behalf of Commonwealth fishing operators to the Department of Agriculture, Water and the Environment (DAWE). These are summarised below.

In 2020, logbooks indicated that 1,226 shortfin mako sharks (Isurus oxyrinchus) were hooked in the ETBF. Of these, 28 were alive, 396 were dead and 802 were released in unknown condition. Four longfin mako sharks (I. paucus) were also hooked, with 1 dead and 3 released in unknown condition. Two porbeagle sharks (Lamna nasus) were dead and 1 was released in an unknown condition, 2 manta rays (Mobula birostris) were released alive and 264 silky sharks (Carcharhinus falciformis) were released in unknown condition. Thirty-one green turtles (Chelonia mydas) were hooked; 25 were released alive and 6 were dead. Twenty-one leatherback turtles (Dermochelys coriacea) were released alive, and 13 loggerhead turtles (Caretta caretta) were hooked with 11 released alive and 2 dead. Three hawksbill turtles (Eretmochelys imbricata) were hooked, with 1 alive, 1 dead and 1 released in an unknown condition. Seven olive ridley turtles (Lepidochelys olivacea) were caught, with 5 released alive and 2 dead. Twenty unidentified turtles were hooked, with 16 alive and 4 dead.

Fourteen unidentified birds were hooked, with 3 released alive and 11 dead. Three black-browed albatrosses (Thalassarche melanophris) were hooked; 2 were alive and 1 was dead. One shy albatross (T. cauta) was released alive. Eight unclassified petrels and shearwaters were dead, as was an unidentified tern. Nine unidentified albatrosses were hooked, with 1 released alive, 7 dead and 1 released in an unknown condition. One sooty shearwater (Ardenna grisea) was released alive. One Australian gannet (Morus serrator) was released alive and 2 were dead.

A number of interactions with marine mammals were recorded; these comprised 4 unidentified dolphins (all released alive), 1 bottlenose dolphin (Tursiops truncatus) released alive and 3 common dolphins (Delphinus spp.) – 2 released alive and 1 dead. In addition, 1 short-finned pilot whale (Globicephala macrorhynchus), 3 false killer whales (Pseudorca crassidens), 2 melon-headed whales (Peponocephala electra) and 1 unidentified seal were released alive. Two unidentified whales were alive and 1 was dead.

These reported interactions with protected species form part of the ongoing monitoring by DAWE of the performance of fisheries within their accreditation under the EPBC Act.

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Kasapidis, P, Magoulas, A, Gacía-Cortés, B & Mejuto, J 2008, Stock structure of swordfish (Xiphias gladius) in the Pacific Ocean using microsatellite DNA markers, working paper WCPFC-SC4-2008/BI-WP-04, WCPFC Scientific Committee 4th regular session, Port Moresby, Papua New Guinea, 11 to 22 August 2008.

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