Shark Depredation and Unwanted Bycatch in Pelagic Longline

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Shark Depredation and Unwanted Bycatch in Pelagic Longline Fisheries Table A3.1. Number of licences issued to tuna longline vessels to fish in Fiji waters (Fiji Department of Fisheries Annual Report, 2004; Raiwaliu Pers. Comm.). Year Number of Licences 2002 103 2003 101 2004 84 2005 72 2006 66 Longline vessels that are licensed to fish in Fiji waters range in size from 14.65 to 37 metres or 19 to 225 Gross Registered Tonnage (GRT). According to interviewees, the vessels that fish on the high seas and in other Pacific EEZ’s quoted their vessel sizes as ranging from 33 to 40 GRT, while the vessels that only fish in Fiji’s EEZ quoted their vessel size as ranging from 13 metres to 29 m. There is an unquantified level of illegal, unregulated and unreported fishing in Fiji’s waters. In a recent case, a Taiwan-owned vessel was charged for illegally targeting shark in Fiji waters. Section A3.7 provides more information about this case. The total allowable catch for the tuna longline industry in Fiji Waters is 15,000 metric tons (Raiwailui Pers. comm., 2006). A total of 50,082,240 hooks were set by the Fiji longline tuna fleets in 2004, a total of 1,997 fishing trips were made by the same fleet that year (Fisheries Department, 2004). This is the most current year for which these statistics are available. A3.4. Range of Fishing Gear and Methods Table A3.2 summarises the general fishing methods and gear of the Fiji longline tuna fishery as indicated by the interviews described in Section 2. Table A3.2. Fishing gear and methods of Fiji-based pelagic longline tuna fisheries. Interview Results Fishing gear and method Only operate in Fiji’s EEZ (4 interviewees) Operate on High Seas, Solomons. Vanuatu and Fiji EEZs (2 interviewees) Trip duration 9 days (2 days travel, 7 days fishing) 1 Around 30 days. Number of sets per trip 7 20-25 Fishing grounds Grounds vary depending on the season. Fiji, Vanuatu, Solomon Islands EEZ and High Seas. Fishing seasons Seasonal, different areas are fished at different times of year. Year round. Annual effort (total catch) 80-100 tonnes. 3000 tonnes Typical length of set (distance line is set over water) 35 to 40 nautical miles (65-74 km) Mainline material Nylon Mainline average length 35 nautical miles 50 nautical miles Distance between buoys 90 - 100 metres 700 metres Distance from buoy to mainline (float line length) 10 fathoms 20 metres Average branch line length 8 fathoms 15 metres Branch line material Nylon Wire trace or leader on branch lines Yes, nylon leader (app. 40-45 Miles) Yes, PE leader (0.5 metres) Setting depth of hooks 60-90 fathoms 50-300 metres Timing of set, soak, and haul Set: 4 to 5am to 7am; Haul: 3pm to 6pm Set: 5am to 10 or 11am; Haul: 12pm-2am Lightstick use Not used Yes (3M product placed only on float) Number of branchlines per set 2300-2400 2500 Number of branchlines between buoys 35 25 Number of hooks per set 2300 - 2500 2500 Hook type Weight size and location B3 or Mustad Interviewees did not know Clip size and type Snap or U-Snap (4mm x 140) Bait type Sardine and Pilchard Pilchard (approx 80-90 grammes) Number of crew 8 to 12 crew 1 These vessels time at sea is limited to how long the ice that they carry can keep the fish frozen. 68
Fiji Pelagic Longline Tuna Fishery A3.5. Catch and Discard Rates of Target and Bycatch Species The data in Table 3 were provided by the Secretariat of the Pacific Commission’s Oceanic Fisheries Programme (SPC OFP) which has compiled observer programme data provided by the Fiji Government. It is important to note that observer coverage is very low, particularly for 1999 to 2004, hence may not be representative. Observer coverage ranges from 4.51% to 0.34% of hooks observed out of the total fishing effort per year (Lawson, Pers. comm.). The data in Table A3.4 come from catch logsheets completed by vessels and provided to the Fiji Fisheries Department as a condition of the licence. Logsheets do not provide full coverage of activities and have been extrapolated by the Fisheries Department to account for missing data. According to SPC data, over the five years for which observer programme data are available, sharks formed 3 - 10% of the catch per effort and 8 to 25% of the weight of the catch per effort. According to the Fiji Fisheries Department’s data in 2004, sharks comprise 6% of the total catch by weight that year while SPC indicated that sharks comprised 14%. Another contradiction is that, according to a 1999 study, sharks formed a major portion of the tuna longline fishery at that time. The data supplied by observers on local vessels showed that sharks comprised > 25% (by number) of the total catch, most of which was discarded (Swamy, 1999). However, these data do not reflect what proportion of this catch was retained or discarded. SPC Observer Programme Data for 1999 and 2002 to 2005 (Table A3.5) indicate that, of the sharks that were observed being caught, 78 to 90% were finned and 82 to 94% were discarded. A significantly larger proportion of the shark catch was alive when hauled to the boat, most of the small proportion of sharks that were discarded were dead at that stage. Tables A3.6 to A3.8 indicate catch, mortality and discard rates for the three most commonly caught shark species as indicated by SPC observer programme data. According to the data the three most commonly caught species in order of most to less common are: Blue Shark (Prionace glauca); Oceanic Whitetip Shark (Carcharhinus longimanus); and Silky Shark (Carcharhinus falciformis). The data for each of the three species reinforce the pattern indicated by observer data which is that sharks are mostly alive when hauled in and mostly dead when discarded. This is contradicted by the interview results which state that the sharks are almost always dead when hauled to the boat. The interviews with fishermen also gave different results for the most commonly caught sharks. According to the interviews with fishermen that only fish in Fiji Waters, sharks that are typically caught are: Makos, Brown Sharks and Blue Sharks. One interviewee indicated that Brown and Blue sharks are the most destructive to their target catch, the rest of the interviewees were not sure. According to the interviewees, sharks are caught at a rate of roughly one to two sharks per set (2300 to 2500 hooks). One interviewee commented that due to the fact that the length of their fishing trips are limited to around 9 days due to ice supplies they catch fewer sharks than Chinese and Japanese longliners which can stay are sea for much longer periods of time. Table A3.2. Target Species (Tuna – Albacore, Bigeye, Yellowfin), Sharks and “Other” observed catch, Fiji Pelagic Longline Tuna Fishery Catch Data, 1999 and 2002-2005, for all fish caught regardless of whether retained or discarded. Source: SPC Observer Programme Data. 1999 No. /100 hooks % Kg/100 Hooks % Tuna 1.756 49 33.473 46 Sharks 0.3581 10 17.9829 25 Other 1.4837 41 21.0125 29 Total 3.5978 72.4684 2002 No. /100 hooks % Kg/100 Hooks % Tuna 1.803 54 32.03 67 Sharks 0.0885 3 3.8017 8 Other 1.4646 44 12.236 25 Total 3.3561 48.0677 2003 No. /100 hooks % Kg/100 Hooks % Tuna 1.323 62 24.414 62 Sharks 0.0819 4 4.3062 11 Other 0.7346 34 10.392 27 Total 2.1395 39.1122 2004 No. /100 hooks % Kg/100 Hooks % Tuna 1.774 74 30.487 72 Sharks 0.1463 6 5.8829 14 Other 0.4633 19 6.2142 15 Total 2.3836 42.5841 2005 No. /100 hooks % Kg/100 Hooks % Tuna 1.916 72 33.461 73 Sharks 0.1072 4 4.7502 10 Other 0.6489 24 7.6622 17 Total 2.6721 45.8734 69
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Shark Depredation and Unwanted Byca
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Contents Summary and Conclusions 1
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Contents Appendix 3. Fiji Pelagic L
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Contents Appendix 8. USA Hawaii Lon
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Chapter 1 Introduction and Methods
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Introduction and Methods 1.2. Metho
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Fishing Gear and Operational Charac
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Fishing Gear and Operational Charac
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Shark Catch Rates and Disposition T
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Chapter 4 National and Internationa
Page 31 and 32: National and International Measures
Page 33 and 34: Economic, Practical, Ecological and
Page 35 and 36: Economic, Practical, Ecological and
Page 37 and 38: Chapter 6 Industry Attitudes and Pr
Page 39 and 40: Industry Attitudes and Practices Lo
Page 41 and 42: Industry Attitudes and Practices Fi
Page 43 and 44: Chapter 7 Potential of Deterrents,
Page 45 and 46: Potential of Deterrents, Hotspot Av
Page 47 and 48: References Campana, S.E., L. Marks,
Page 49: References Neves dos Santos, M., Ga
Page 52 and 53: Shark Depredation and Unwanted Byca
Page 99 and 100: Appendix 5 Japan Pelagic Longline F
Page 101 and 102: Japan Pelagic Longline Fisheries Fi
Page 103 and 104: Japan Pelagic Longline Fisheries mo
Page 105 and 106: Japan Pelagic Longline Fisheries Ta
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Page 109 and 110: Japan Pelagic Longline Fisheries ta
Page 111 and 112: Japan Pelagic Longline Fisheries In
Page 113 and 114: Japan Pelagic Longline Fisheries A5
Page 115 and 116: Appendix 6 Peru Artisanal Mahimahi
Page 117 and 118: Peru Artisanal Mahimahi And Shark L
Page 127 and 128: Appendix 7 South Africa Pelagic Lon
Page 129 and 130: South Africa Pelagic Longline Tuna
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South Africa Pelagic Longline Tuna
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Appendix 8 USA Hawaii-based Pelagic
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USA Hawaii-based Pelagic Longline S
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Appendix 9 USA Atlantic, Gulf of Me
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USA Atlantic, Gulf of Mexico and Ca
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Shark Depredation and Unwanted Bycatch in Pelagic Longline

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