SCTB17 Working Paper NFR 17 New Zealand Tuna Fisheries in 2002 and 2003 Terese Kendrick 1, Talbot Murray 2 and Susan Jane Baird 3 1 Trophia Ltd., P.O. Box 60, Kaikoura, NZ 2 Ministry of Fisheries, P.O. Box 1020, Wellington, NZ 3 National Institute of Water & Atmospheric Research, Ltd., P.O. Box 14-901, Wellington, NZ July 2004
SCTB 17 Working Paper NFR 17 New Zealand Tuna Fisheries in 2002 and 2003 Terese Kendrick 1, Talbot Murray 2 and Susan Jane Baird 3 1 Trophia Ltd., P.O. Box 60, Kaikoura, NZ 2 Ministry of Fisheries, P.O. Box 1020, Wellington, NZ 3 National Institute of Water & Atmospheric Research, Ltd., P.O. Box 14-901, Wellington, NZ
Introduction New Zealand tuna fisheries are based on the principal market species: albacore (Thunnus alalunga), bigeye (T. obesus), Pacific bluefin (T. orientalis), southern bluefin (T. maccoyii), skipjack (Katsuwonus pelamis) and yellowfin tunas (T. albacares). A range of gear types including purse seine, troll, longline, and occasionally pole-&-line and handline are used to catch these species. Most tunas and swordfish are being considered for inclusion in the Quota Management System (QMS) with bigeye, southern bluefin, Pacific bluefin, and yellowfin tunas, and swordfish to be introduced into the QMS from October 2004 and albacore and skipjack tuna from October 2005. Only southern bluefin tuna (T. maccoyii), is currently subject to catch restrictions, with a 420 t competitive national catch limit. Tuna-like species slender tuna (Allothunnus fallai) and butterfly tuna (Gasterochisma melampus) are also caught but have little or no commercial value. Striped marlin (Tetrapturus audax) is the main target species of a well-established recreational sport fishery for marlin in northern New Zealand. While billfish are also regularly a non-target catch on tuna longlines, no billfish except swordfish (Xiphias gladius) can be kept (whether alive or dead) when caught. Swordfish catches are an important component of the domestic tuna longline fishery. New Zealand tuna fisheries began in the early 1960s with small but regular troll landings each year, usually of skipjack and albacore. These fisheries developed during the 1970s into the summer albacore troll and skipjack purse seine fisheries. During the 1980s, the domestic handline and troll fishery for southern bluefin tuna developed in winter months and continues to operate in some years. Starting in 1991, domestic longlining progressively expanded to displace foreign licensed longlining previously done by foreign licensed vessels from Japan and Korea. Today New Zealand tuna fisheries target all commercially valuable tuna species when they are present in the EEZ, and tuna fishing, once regarded as minor seasonal fisheries controlled by climatic factors and weather, is now a year-round activity. In addition to tuna fishing in the EEZ, New Zealand fishers (1989 to 1997) fishing over 1000 miles east of New Zealand, helped to establish the high seas troll fishery for albacore that is now primarily the domain of troll vessels from the USA and Canada. A more recent development has been the entry of New Zealand (formerly USA and Canadian) Class-6 purse seiners operating under the FSM Agreement in the equatorial western Pacific for skipjack, yellowfin, and bigeye tunas. This report covers New Zealand flagged vessels, both chartered and domestic owned and operated, fishing within and beyond the EEZ. Domestic catches, all species and all gears combined 1999 2003 The catch of all tunas and swordfish inside the EEZ peaked in 2000 at around 16,000 t, dropping by about a third in 2001 to return to previous levels. Total catches have been about 11,000 t since 2000 with the decline due to lower catches of skipjack (from 9700 t in 2000, to 3700 t in 2001). Catches of all other species except southern bluefin tuna, increased in 2001. In the most recent three years there has been a decline in catches of bigeye (from 480 t in 2001, to 157 t in 2003), yellowfin (from 137 t in 2001 to 35 t in 2003) and of swordfish (from 1030 t in 2001 to 620 t in 2003). Catches of albacore, skipjack and southern bluefin tuna have all increased slightly, maintaining the level of total removals (Table 1).
Table 1: Landed whole weight (t) of fish caught inside the New Zealand EEZ, by all fishing methods, and vessels combined, for calendar years 1999 to 2003. Scaled to totals from Licensed Fish Receivers in New Zealand for 1999 to 2001, and to totals of Monthly Harvest Returns from Permit Holders for 2002 and 2003. Calendar Pacific Southern year Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish EEZ total 1999 3903 421 5688 21 461 154 1004 11 652 2000 4500 422 9699 21 380 107 975 16 104 2001 5353 480 3691 50 358 137 1029 11 099 2002* 5544 200 3321 56 463 25 917 10 526 2003* 5991 157 3850 37 389 35 619 11 077 Licensed Fish Receiver returns (LFRR) * Monthly Harvest Returns from permit holders (MHR); MHR data has been used in the most recent years because this is essentially the same as the LFR data available earlier but also enables in-zone and extra-territorial catches landed in New Zealand to be distinguished. The use of MFR or LFR data does not affect the scaling to total landings. Domestic fleet structure 1999 2003 The domestic longline fleet increased exponentially after the start of that fishery in 1991, but from 1999 to 2002 the number of longline vessels targeting tuna was constant at around 80 vessels. The number of vessels trolling for tunas increased from 187 in 1999, to a peak of 273 in 2001, and has since declined to less than 200 vessels in 2003. The number of dedicated longline vessels also dropped by almost half in 2003, with a net loss of 89 vessels from the longline and troll fleets combined between 2002 and 2003. The number of vessels using both troll and longline during the year, although increasing steadily from 8 in 1999 to 80 in 2003 did not offset the net loss of vessels. The number of purse-seiners has been low and stable over the period at fewer than 10 vessels in each year, though they account for a disproportionate amount of the tuna catch. Very few vessels have reported fishing using pole-&-line. Apart from vessels targeting tuna, a further 30 to 50 vessels landed small amounts of tuna or swordfish in each year by other methods, chiefly as a bycatch in other fisheries (Table 2). Table 2: Number of vessels that targeted tunas by the main tuna methods and that landed tunas as bycatch of other fisheries from inside the New Zealand EEZ for 1999 to 2003. Longline & troll indicates the number of vessels that used both methods within the year depending on season. Fishing method 1999 2000 2001 2002 2003 Troll 187 256 273 253 199 Longline 76 83 75 83 48 Troll & Longline 8 26 57 69 80 Purse seine 6 7 8 8 7 Pole-&-line 4 3 2 2 1 Other & non-targeted 50 42 45 31 42 Total vessels 144 161 187 193 178 Domestic fleet structure and total catch by method in 2002 and in 2003 In 2002, the proportion of vessels by number that fished in the EEZ by trolling made up most (57%) of the fleet targeting tunas, while 19% of vessels fished by longline, and an additional 15% of the fleet switched between the two methods during the year. Around 7% of the vessels landed tunas or swordfish as a by-catch in other fisheries, and 2% of the fleet used purse seine (Figure 1).
The total catch in 2002, by contrast, was almost equally caught between purse seine (30%), longline (36%) and troll vessels (34%), with the non-target and other (including pole-&-line) catches accounting for less than 1% of the landings (Figure 1). The eight purse-seiners (2% of the total tuna fleet) were the highest-catching vessels in the EEZ. Overall, the top 20% of vessels accounted for 70% of total landings, and the top 55% of the vessels landed 95% of tuna and swordfish caught inside the EEZ in 2002. One purse-seiner, one troll vessel, and nineteen longliners from the domestic fleet also reported catches from high seas waters outside the EEZ in 2002 (Table 5). In addition and four vessels were licensed to purse seiner in the EEZs of other Pacific Island States under the FSM Arrangement. Pole-&-line 0.4% Purse seine 2% Other & nontargeted 7% Longline 19% Purse seine 30% Pole-&-line < 0% Other & nontargeted 0.3% Longline 36% Both longline & troll 15% Troll 57% Number of vessels 2002 Troll 34% Greenweight of tunas 2002 Figure 1: Percentage of vessels that targeted tunas by the main tuna fishing methods inside the New Zealand EEZ in 2002, or landed tunas as a bycatch of other fisheries. Percentage of landed whole weight of all species combined (tunas and swordfish) taken by targeted longline, troll, purse seine, pole-&-line fishing, and as a bycatch of other fisheries. Longline/troll indicates vessels that used both methods seasonally during the year. In 2003, the number of vessels declined by 8% while total catch increased by 5%. Troll vessels dominated the fleet (53%), with another 13% of the fleet fishing only by longline. An additional 21% used both troll and longline during 2003, while 11% of vessels landing tuna or swordfish used other methods. As in 2002, 2% of the fleet used purse seine (Figure 2). Longline vessels accounted for just 29% of the total catch in 2003, although two chartered Philippine longliners were among the top catching vessels of 2003, ranking 5 th and 6 th among the eight highest catching vessels (the others being purse-seiners). Purse seining accounted for 33% of the annual tuna and swordfish catch, and troll took 38% (Figure 2). As in 2002, 55% of the vessels landed 95% of tuna and swordfish caught in the EEZ. One purse seine, one troll, and seven longline vessels also made catches outside the EEZ on the high seas (Table 5) and four vessels were licensed to purse seine within the EEZs of other Pacific Island States under the FSM Arrangement.
Pole-&-line 0.3% Purse seine 2% Other & nontargeted 11% Longline 13% Pole-&-line 0.02% Purse seine 33% Other & nontargeted 0.3% Longline 29% Both Longline & troll 21% Troll 53% Number of vessels 2003 Troll 38% Greenweight of tunas 2003 Figure 2: Percentage of vessels that targeted tunas by the main tuna fishing methods inside the New Zealand EEZ in 2003, or landed tunas as a bycatch in other fisheries. Percentage of landed whole weight of all species combined (tunas and swordfish) taken by targeted longline, troll, purse seine, pole-&-line fishing, and as a bycatch in other fisheries. Longline/troll indicates vessels that used both methods seasonally during the year. Domestic catch by species, gear type, and season, in 2002 and in 2003 Longline effort in New Zealand is largely targeted at bigeye and southern bluefin tunas, and accounts for almost all of the catch of those species. Most albacore was taken by trolling: 62% by weight in 2002, and 67% in 2003, with the balance mainly taken by longline. Skipjack was taken almost entirely (98% by weight) by purse seine in 2002, and though just 84% was taken by purse seine in 2003, the actual tonnage was greater by 570 t. Small amounts of skipjack are also taken by longline and trolling. Between 10 and 20% of swordfish (by weight) is taken in fisheries not targeting tunas, primarily bottom and midwater trawls. These methods also have a small bycatch of other tuna species (Table 3 and 4). Longline fishing is carried out throughout the year, with effort peaking during autumn and early winter. Trolling and purse seining are both seasonal (summer) fisheries, with trolling taking place over a longer period (November to May) than purse seining, which is restricted in most years to the 3 to 4 months of summer. The seasonal distribution of catches by species reflects the seasonal patterns of effort for the main fishing methods. Skipjack catches are greatest during January to April, as are catches of albacore, however albacore is caught starting in December through to October or November. Trolling for juveniles finishes after May, but larger albacore are caught throughout the year by longline (Figures 3 and 4). Swordfish and the bluefin tunas are caught throughout the year but peak during early winter. Bigeye and yellowfin are caught in small numbers throughout the year, but appear to be least available during May and June (Figures 3 and 4).
Table 3: Domestic catch (whole weight, t) for 2002 by species and gear type adjusted to MHR totals for all tunas caught inside the New Zealand EEZ, (0.0 refers to catches < 100 kg). Fishing Pacific Southern method Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish Longline 2084.6 199.4 17.0 55.3 460.0 23.6 905.7 Purse seine 0.5 0.0 3257.1 0.0 0.0 0.0 0.0 Troll 3456.1 0.7 46.5 0.0 0.5 0.8 0.8 Pole-&-line 0.1 0.0 0.0 0.0 0.0 0.0 0.0 Other 2.9 0.3 0.2 1.0 2.1 0.9 10.2 Total (t) 5544.3 200.3 3320.8 56.3 462.6 25.3 916.7 PL PS T SLL Days Jan Mar May Jul Sep Nov YFN TOR SWO STN SKJ BIG ALB Tonnes Jan Mar May Jul Sep Nov Figure 3: Relative seasonal effort by method (vessel-days fished) and catch (t) by species by month for 2002. Table 4: Domestic catch (whole weight, t) for 2003 by species and gear type adjusted to MHR totals for all tunas caught inside the New Zealand EEZ, (0.0 refers to catches < 100 kg). Fishing Pacific Southern method Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish Longline 1999.5 156.7 11.4 36.7 387.2 34.0 606.1 Purse seine 2.9 0.0 3826.1 0.0 0.0 0.0 0.0 Troll 3977.0 0.4 12.5 0.0 0.1 0.4 0.6 Pole-&-line 2.5 0.0 0.0 0.0 0.0 0.0 0.0 Other 8.8 0.0 0.0 0.0 1.4 0.1 12.6 Total (t) 5990.7 157.2 3850.0 36.7 388.7 34.5 619.3
PL PS T SLL Days Jan Mar May Jul Sep Nov YFN TOR SWO STN SKJ BIG ALB Tonnes Jan Mar May Jul Sep Nov Figure 4: Relative seasonal effort by method (vessel-days fished) and catch (t) by species by month for 2003. The albacore troll fishery takes place in summer and autumn. The catches for the albacore surface fishery (approximated by the New Zealand fishing year, 1 October to 30 September) in 2001/02 and 2002/03 were 3257 t and 4073 t respectively. Fishing by New Zealand flagged vessels in high seas areas and in the EEZs of other Pacific Islands A few domestic vessels have fished outside the New Zealand EEZ using troll, longline or purse seine in each year, mostly in waters adjacent to the EEZ. New Zealand flagged vessels have also fished under license in the EEZs of Pacific Island States under the FSM Arrangement and in high seas areas of the equatorial western and central Pacific Ocean using purse seine since 2000. Since October 2001, permit holders have been required to fill out Monthly Harvest Returns that allow the actual landed (in New Zealand) whole-weight of fish taken outside the New Zealand EEZ to be differentiated from landings of fish taken within the NZ EEZ, however, the landed weight of fish that were sold offshore (not through New Zealand licensed fish receivers) was estimated through FFA logsheet data. Table 5: Estimated whole weight (t) of fish caught by New Zealand flagged vessels outside of the New Zealand EEZ, for calendar years 1999 to 2003. Pacific Southern Year Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish Total 1999 16 2 1 1 1 5 26 2000 10 10 53 1 4 11 88 2001 30 11 1 378 2 599 20 2 039 2002 22 8 13 613 2 3 269 8 16 922 2003 43 10 14 520 3 515 1 18 089 Total catches by species is given for New Zealand flagged vessels fishing outside the EEZ (including the EEZs of other Pacific Island countries) in Table 5. In 2002, the catch of all species, largely taken by four purse seine vessels, comprised mainly of skipjack (80%) with the balance mostly yellowfin totaled 16,922 t, which is considerably more that the total catch from within the New Zealand EEZ. In 2003 the same four vessels also accounted for most of the non-new Zealand EEZ catch of around 18,000 t, 80% of which was skipjack, with most of the rest being yellowfin. Yellowfin tuna are not part of the purse seine catch in New Zealand waters.
Table 6: Estimated whole weight (t) of fish caught by New Zealand flagged vessels outside the New Zealand EEZ in 2002 by species and gear type, (0.0 refers to catches < 100 kg). Fishing Pacific Southern Method Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish Longline 20.1 3.4 0.3 0.0 2.0 1.9 7.7 Purse seine 0.0 5.0 13 613.0 0.0 0.0 3 267.1 0.0 Troll 1.4 0.0 0.1 0.0 0.0 0.0 0.0 Total 21.5 8.4 13 613.4 0.0 2.0 3 269.0 7.7 Table 7: Estimated whole weight (t) of fish caught by New Zealand flagged vessels outside the New Zealand EEZ in 2003 by species and gear type, (0.0 refers to catches < 100 kg). Fishing Pacific Southern Method Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish Longline 40.9 1.9 0.2 0.2 0.0 4.1 1.2 Purse seine 0.0 8.0 14 519.7 0.0 0.0 3 510.0 0.0 Troll 2.2 0.0 0.0 0.0 0.0 0.6 0.0 Total 43.1 9.9 14 519.9 0.2 0.0 3 514.7 1.2 The total tuna and swordfish catch by New Zealand flagged vessels in 2002 and 2003 is given in Table 8. Table 8: Estimated whole weight (t) of fish caught by New Zealand flagged vessels fishing in the western and central Pacific Ocean in 2002 and 2003 by species, (0.0 refers to catches < 100 kg). Pacific Southern Area Caught Albacore Bigeye Skipjack bluefin bluefin Yellowfin Swordfish 2002 NZ EEZ 5 544 200 3 321 56 463 25 917 High Seas 22 3 2 662 2 647 8 Other EEZs 5 10 951 2 622 Total 5 566 208 16 934 56 465 3 294 925 2003 NZ EEZ 5 991 157 3 850 37 389 35 619 High Seas* 43 10 2 839 0 695 1 Other EEZs* 11 680 2 815 Total 6 034 167 18 370 37 389 3 545 620 * provisional figures based on copies of commercial logsheets held by the Ministry of Fisheries, data not all held by SPC; breakdown of total non-eez catch of skipjack and yellowfin based on proportions of high seas and other EEZs in 2002 Bycatch in New Zealand Tuna fisheries Bycatch is a feature of many tuna fisheries, particularly those using longline and purse seine. In New Zealand tuna fisheries only longline fisheries have received adequate observer coverage to enable characterization of the bycatch. However, the Ministry of Fisheries is planning observer coverage in the purse seine fishery with a target of 20% coverage. The target for the longline fishery is 10%. Fish bycatch in the New Zealand longline fishery is summarized in working paper ECO-6 of this meeting, while seabird bycatch is summarized in Appendix 1 of this report.
Markets The two main markets for New Zealand caught tuna are canning (skipjack and albacore) and the fresh-chilled and frozen sashimi market (other large tunas and swordfish). Canning is done outside of New Zealand where labour costs are lower. Spain and the United States of America are important markets for canned albacore while Indonesia and Thailand are important for skipjack. Fresh and frozen southern bluefin, Pacific bluefin, and yellowfin tunas and swordfish are exported primarily to Japan, Australia and the United States of America. Some domestic consumption of fresh and smoked tuna occurs, but the volume is small. Fisheries represent New Zealand s fourth largest export earner, but has undergone a significant decline, particularly in the last year. Export revenues that peaked at $NZ 1.5 billion in 2001 and 2002 declined to $NZ 1.2 billion in 2003, primarily due to the rapid strengthening of the New Zealand dollar against the US dollar 4. Tuna export earnings began to decline in 2001 and reflects a 20% drop in earnings despite an increase in the amount exported over the period ( www.seafood.co.nz based on data from Statistics New Zealand). During this period, vessel numbers have declined by about 30 % while tuna landings do not show the same trend (high in 2001 and 2003 but low in 2002). The reasons for this discrepancy are unknown but may relate to errors and/or lack of validation of the export statistics for tuna. The decline in export earnings together with the introduction of tunas and swordfish to the QMS may explain the sharp decline in tuna vessel numbers over the last three years. Future prospects and developments Tuna species and swordfish will enter into the QMS from October 2004 (bigeye, southern bluefin, Pacific bluefin and yellowfin tunas and swordfish). With entry into the QMS, fishers with recognized catch history will receive a property right to these fisheries in the form of an individual transferable quota (ITQ). It is expected that once this happens, fishers will rationalize their investments in fishing and optimize their tuna catching, as has occurred in other New Zealand fisheries. Fishers without an ITQ will not be able to retain catch. In essence we expect to continue to see a shift in fishing towards the better and more efficient operators in the industry. A new development, signaling a change in skipjack purse seine fishing operations, began in 2004. This involved a significant increase in purse seine fishing effort by New Zealand flagged Class-6 purse seiners within the New Zealand EEZ. Vessels began fishing for skipjack in November 2003 and continued fishing into June. The end of the season was brought on by other commitments of vessels and skipjack schools were reported as having moved well inshore, forming mixed schools with mackerel. Only vessels holding quota for mackerel and vessels with shallower nets could continue fishing, although skipjack were still present in good quantities. In addition, a higher number of aerial spotting flights were conducted to locate schools in 2004, especially in the Tasman Sea off the west coast of the North Island. Large seiners also fished co-operatively with the smaller sized New Zealand based purse seiners. The smaller vessels landing catch to Onehunga to reduce steaming times to their normal unloading ports. It is estimated that despite little fishing being done in February because of bad weather, the Class-6 seiners caught approximately 5,000 t with the smaller seiners also catching about 5,000 t (2,000 t on the east coast and 3,000 t on the west coast). This change in fishing strategy effectively doubled the within EEZ catch of skipjack normally realized. Only two large seiners were involved in 2004 but it is likely that all four New Zealand flagged Class-6 vessels will be fishing in this manner next year. 4 Ministry of Fisheries Statement of Intent 2004/08.
Acknowledgements This report is based on work done for project TUN2003-02 on contract to the Ministry of Fisheries, New Zealand. Thanks also to Neville Smith and Shelton Harley of the New Zealand Ministry of Fisheries for critically reviewing the paper. Thanks are also due to Angela Roskam for compiling catch statistics for high seas areas. Thanks to Vaughn Wilkinson (Simunovitch Fisheries Ltd.), Ian van der Nagel (Sanford s Ltd.), and Martin de Beer (Sanfords Ltd.) for information on purse seine fishing in 2004.
Appendix 1. Summary chartered tuna longline fishing effort and seabird catch statistics for 2000 01 to 2002 03, prepared for the New Zealand NPOA Technical Working Group meeting 22 June 2004. The material presented here is for the three most recent fishing years, 2000-01 to 2002-03, and summarises data presented in reports completed for Ministry of Fisheries (MFish) project ENV2001/01 for the years 2000-01 and 2001-02. The 2002-03 data should be considered as preliminary. Effort data are from MFish catch and effort databases and observer databases. For each fishery, tables give the summary statistics by fishing year or season, and figures show fishery areas and distribution of observed data and vessel-area catch rates and incident rates. Note: estimates of seabird captures are only given where there at least 10% of the effort covered observed seabird captures comprise all seabirds (dead and alive) observed by the MFish observer during the period of observation on chartered tuna longliners observer coverage is expressed as the percent of the hooks observed incident rates are the percents of observed sets with observed seabird captures the 25 th percentiles are displayed for vessel catch rates. This fishery usually operates between March-June targeting southern bluefin tuna, mainly in the waters south of 40º S, particularly off the southern west coast of the South Island. The same four vessels have fished in the three years covered here. Areas are shown in Figure 1. Table 1: Summary seabird statistics for chartered tuna longline fisheries, 2001 to 2003. Target fishery area Total no. hooks % hooks observed No. observed seabirds Incident rate (%) Mean bycatch rate Standard error Estimated no. seabirds caught c.v. (%) 2001 Area 1 0 Area 2 53 010 100 1 6 0.019 0.017 2 0 Area 3 567 998 95 14 6 0.026 0.008 15 7 Area 4 0 2002 Area 1 0 Area 2 22 100 95 1 14 0.050 0.044 1 Area 3 692 372 93 75 22 0.116 0.018 80 4 Area 4 12 006 98 0 0 0.000 2003 Area 1 9 470 96 0 0 0.000 Area 2 0 Area 3 870 990 93 42 11 0.052 0.011 45 6 Area 4 70 770 85 0 0 0.000
Area 4 Area 4 35 35 40 Area 3 2001 2002 40 Area 1 Area 3 Area 1 45 Area 2 45 Area 2 50 S 50 S 165 E 170 175 180 175 165 E 170 175 180 175 Area 4 35 40 Area 3 Area 1 2003 45 Area 2 50 S 165 E 170 175 180 175 Figure 1: Start positions of observed sets ( ), including those with seabird bycatch ( ), for chartered Japanese vessels, 2001 03.
25 th percentile at 0.023 2001 250 0.25 200 150 100 50 0.20 0.15 0.10 0.05 0 0.0 No. observed sets 4 1 3 2 25 th percentile at 0.079 2002 250 0.25 200 0.20 150 0.15 100 0.10 50 0.05 0 0.0 1 4 3 2 25 th percentile at 0.032 2003 250 0.25 200 0.20 Mean seabird CPUE (95% CI) Incident rate (%) 30 25 20 15 10 2001 2002 2003 150 0.15 100 50 0.10 0.05 5 0 0.0 3 4 2 1 Vessel 0 1 2 3 4 Vessel Figure 2: Number of observed sets and mean seabird catch rates for each vessel targeting tuna in Area 3, with 25 th percentiles displayed for vessel catch rates, 2001 03. Figure 3: Incident rates (number of sets with observed seabird captures) for the four chartered tuna longline vessels, by year (season).