Agenda Item K.5.b Supplemental HMSMT Report 2 March 2014 HIGHLY MIGRATORY SPECIES MANAGEMENT TEAM REPORT ON DRIFT GILLNET MONITORING, MANAGEMENT, AND ALTERNATIVE GEAR REPORT 1. Analysis of Potential Effort, Finfish Catch and Relative Bycatch Rates The Highly Migratory Species Management Team (HMSMT) provided a placeholder in its March 2014 report on drift gillnet (DGN) management for an analysis of potential effort, finfish catch, and relative bycatch rates in the area under consideration (AUC) for reopening. This information is summarized here. DGN observer data 1 from 1990-2000 were used to compute ratios of leatherback turtle bycatchper-unit-effort (BPUE) to swordfish catch-per-unit-effort (CPUE) inside the AUC during two time periods. The first, August 15 November 15 (left column of Table 1), has been closed since 2001; the second November 16 January 31 has remained open (middle column of Table 1). The third column reports BPUE/CPUE where DGN effort was observed outside the PLCA. This breakdown contrasts finfish catch rates and protected species bycatch rates within the AUC during the current open and closed periods and outside the PLCA. The estimates demonstrate a considerably higher swordfish CPUE for effort inside the AUC during the closed season. However, the observed leatherback bycatch rate was also higher, as is the ratio of leatherback bycatch to swordfish catch (BPUE/CPUE). It should be noted however that the two observed leatherback interactions within the AUC since it closed are insufficient to test for statistical significance. Table 1. Observed Leatherback/Swordfish (BPUE/CPUE) Ratio by Area and Season, 1990-2000. Observed Leatherback and Swordfish BPUE/CPUE Ratio by Area and Season, 1990-2000 Closed Season, AUC (Aug 15-Nov 15) Open Season, AUC (Nov 16-Jan 31) Non-PLCA Observed Effort (Sets) 321 49 3889 Swordfish Catch (Counts) 976 102 6368 Swordfish CPUE 3.0405 2.0816 1.6374 Leatherback Takes (Counts) 2 0 4 Leatherback BPUE 0.006231 0 0.001029 Leatherback-Swordfish BPUE/CPUE 0.002049 0 0.0006281 1 Observer coverage of drift gillnet effort from 1990 to 2000 was 16.4% of the total number of sets fished over the period. 1
Appendix 1 includes a summary of potential effort, revenues, finfish, and protected species impacts by area and season. A medium effort scenario based on 19 participating vessels was used to estimate expected effort in sets, which was then allocated in proportion to historical effort and catch from 1990 to 2000 inside the AUC or outside the PLCA. Revenues per-set within the fishery were estimated for the 1990s and inflation adjusted to 2013 dollars. Potential impacts were calculated by scaling revenue per set, CPUE, and BPUE rates to low (-25% of the baseline), medium and high (+25% of the baseline) effort scenarios. Figure 1 highlight some of the most relevant statistics from Appendix 1. Swordfish and blue shark CPUE were both higher inside the AUC during the closed season than for either inside the AUC during the period it remained open or outside the PLCA. Common mola, common thresher shark and shortfin mako shark were caught at lower CPUE inside the AUC during the closed season than for other AUC or non-plca effort. 10.0 9.0 8.0 7.0 AUC: Closed Season (Aug 15-Nov 15) AUC: Open Season (Nov 16-Jan 31) Outside PLCA 6.0 CPUE 5.0 4.0 3.0 2.0 1.0 0.0 Albacore Tuna Blue Shark Bluefin Tuna Common Thresher Shark Common Mola Shortfin Mako Shark Swordfish Figure 1. Catch rates for selected finfish in the Area Under Consideration (AUC) compared to the area outside PLCA As indicated in Appendix 1, the leatherback turtle bycatch rate was higher while the sperm whale bycatch rate was appreciably lower for AUC effort during the season that closed after 2000 compared to time-area combinations which remained open to DGN after 2000. These results should be considered subject to the caveats that they are only representative of relative bycatch rates in observer data before 2001 and that rare event bycatch rates are difficult to reliably quantify. HMSMT Discussion of DGN Management with HMSAS The HMSMT held a joint session with the HMSAS at the March 2014 Council meeting to present the HMSMT Report on DGN management and take questions from constituents. The discussion clarified that a total of 25 leatherback sea turtle bycatch observations were made in the history of 2
the NMFS DGN observer program dating back to 1990, and that 10 sperm whales were observed taken over six different sets. A member of the HMSAS asked whether bycatch rates presented in Table 1 of the HMSMT Report on Agenda Item K.5.b could be restated in terms of a comparison of bycatch rates before and after regulatory measures were adopted. The period from 1997 to 2001 included the adoption of recommendations by the Pacific Offshore Cetacean Take Reduction Team to reduce marine mammal bycatch in the DGN, and the establishment in 2001 of the PLCA. Table 2. Comparison of Bycatch Rates Pre-2001 and Post-2000 (Bycatch per 100 sets). Period All Cetaceans Leatherbacks Sperm Whales Pre-2001 8.77 0.385 0.134 Post-2000 5.52 0.084 0.084 Pct Change -37.1% -78.3% -37.5% Table 2 summarizes bycatch rates per 100 drift gillnet sets before 2001 and after 2000 for all cetaceans, leatherback sea turtles and sperm whales. As seen in the table, the observed rate of DGN interactions with all cetaceans and with sperm whales alone was reduced by slightly over 37% after MMPA regulation, while the leatherback sea turtle interaction rate declined by over 78% after ESA regulation. Observer reports included 6 sperm whales reported dead, 2 released alive, and 2 released injured; 11 of 25 leatherback turtles observed as DGN bycatch were released uninjured. CDFW Survey Results At the request of the HMSMT, the California Department of Fish and Wildlife undertook a phone survey of all DGN permittees to gauge their interest in fishing should the PFMC s proposed Area Under Consideration (AUC) be reopened. The preliminary results of the survey are summarized in Appendix 2. Of the 72 issued permits as of February 2014, 54 permit holders have responded to the survey thus far. The respondents held a permit for an average of 22 years up to the present. Twenty-six had not actively fished for swordfish within the last five years while 28 had actively fished within that time. When asked if the potential opening of the AUC would influence their decision to fish in the DGN in the future, 18 permittees replied that it would, 30 said it would not because the area was either too small or too far from their home port, and 6 were unclear on what influence the AUC opening would have. The respondents noted that a host of other factors would ultimately contribute to their final decision to fish or not, for instance swordfish availability and price. The respondents noted the average cost to get ready for DGN fishing in 2014-15 would be approximately $19,000, and 21 responded that it would cost them at least $10,000 to prepare to fish again. Thirty-eight stated they would be able to accommodate observers if so requested. HMSMT RECOMMENDATION TO THE COUNCIL: If the Council choses to open the AUC, eliminate leatherback critical habitat from the AUC. 3
Appendix 1. Summary of Potential Effort, Revenue, Finfish and Protected Species Impacts Closed Season, AUC Open Season, AUC Non-PLCA Low Effort 11 2 266 Revenues ($1000s) $28.0 $5.1 $677.9 Swordfish 33.4455 4.1633 435.5588 Common Thresher Shark 0.2399 0.2449 247.3957 Shortfin Mako Shark 5.3115 1.1020 265.4528 Blue Shark 63.9782 4.1633 684.7328 Albacore Tuna 24.3645 4.1224 341.8534 Bluefin Tuna 16.0031 4.2857 99.7927 Yellowfin Tuna 0.2056 0.0000 16.6891 Bigeye Tuna 0.0343 0.0000 0.8892 Skipjack Tuna 26.4206 0.2857 305.9445 Dorado 0.0000 0.0000 0.0684 Striped Marlin 0.0343 0.0000 20.0406 Leatherback Turtle 0.0685 0.0000 0.2736 Loggerhead Turtle 0.0000 0.0000 1.3680 Humpback Whale 0.0000 0.0000 0.1368 Sperm Whale 0.0343 0.0816 0.1368 Mola Mola 45.5078 17.5102 1,652.4284 Pelagic Thresher Shark 0.0000 0.0000 5.2666 Bigeye Thresher Shark 0.8910 0.0816 14.9792 White Shark 0.0000 0.0000 0.1368 Megamouth Shark 0.0000 0.0000 0.0684 Basking Shark 0.0000 0.0000 0.0684 Medium Effort 14 2 354 Revenues ($1000s) $35.7 $5.1 $902.2 Swordfish 42.5670 4.1633 579.6534 Common Thresher Shark 0.3053 0.2449 329.2409 Shortfin Mako Shark 6.7601 1.1020 353.2718 Blue Shark 81.4268 4.1633 911.2610 Albacore Tuna 31.0093 4.1224 454.9478 Bluefin Tuna 20.3676 4.2857 132.8069 Yellowfin Tuna 0.2617 0.0000 22.2103 Bigeye Tuna 0.0436 0.0000 1.1833 Skipjack Tuna 33.6262 0.2857 407.1592 Dorado 0.0000 0.0000 0.0910 Striped Marlin 0.0436 0.0000 26.6706 Leatherback Turtle 0.0872 0.0000 0.3641 Loggerhead Turtle 0.0000 0.0000 1.8205 Humpback Whale 0.0000 0.0000 0.1821 Sperm Whale 0.0436 0.0816 0.1821 Mola Mola 57.9190 17.5102 2,199.0964 Pelagic Thresher Shark 0.0000 0.0000 7.0090 Bigeye Thresher Shark 1.1340 0.0816 19.9347 White Shark 0.0000 0.0000 0.1821 Megamouth Shark 0.0000 0.0000 0.0910 Basking Shark 0.0000 0.0000 0.0910 High Effort 18 3 443 Revenues ($1000s) $45.9 $7.6 $1,129.0 Swordfish 54.729 6.245 725.385 Common Thresher Shark 0.3925 0.3673 412.0162 Shortfin Mako Shark 8.6916 1.6531 442.0887 Blue Shark 104.6916 6.2449 1,140.3633 Albacore Tuna 39.8692 6.1837 569.3273 Bluefin Tuna 26.1869 6.4286 166.1962 Yellowfin Tuna 0.3364 0.0000 27.7943 Bigeye Tuna 0.0561 0.0000 1.4808 Skipjack Tuna 43.2336 0.4286 509.5240 Dorado 0.0000 0.0000 0.1139 Striped Marlin 0.0561 0.0000 33.3759 Leatherback Turtle 0.1121 0.0000 0.4556 Loggerhead Turtle 0.0000 0.0000 2.2782 Humpback Whale 0.0000 0.0000 0.2278 Sperm Whale 0.0561 0.1224 0.2278 Mola Mola 74.467 26.265 2,751.977 Pelagic Thresher Shark 0.0000 0.0000 8.7711 Bigeye Thresher Shark 1.4579 0.1224 24.9465 White Shark 0.0000 0.0000 0.2278 Megamouth Shark 0.0000 0.0000 0.1139 Basking Shark 0.0000 0.0000 0.1139 4
Appendix 2. Summary CDFW DGN Participant Survey CDFW DRIFT GILL NET SURVEY SUMMARY NUMBER OF PERMITTEES % of SURVEY RESPONSES (n=54) % of ISSUED PERMITS (n=72) TOTAL COMPLETED SURVEYS 54 75.0 AVERAGE NUMBER OF YEARS PERMIT HELD 22 NUMBER PERMITS ACTIVE W/IN LAST 5 SEASONS 28 51.9 38.9 NUMBER PERMITTEES ACTIVE IN OTHER FISHERIES 47 87.0 65.3 2014-15 DGN FISHING SEASON: Plan to fish 20 37.0 27.8 Do not plan to fish 19 35.2 26.4 May possibly fish 7 13.0 9.7 Unknown if will fish 8 14.8 11.1 NUMBER WITH RESOURCES TO FISH DGN 2014-15 SEASON 49 90.7 68.1 AVERAGE DAYS OF PREPARATION TO FISH DGN 2014-15 (n=49) 28 AVERAGE COST OF PREPARATION TO FISH DGN 2014-15 (n=47) $18,798 Permittees w/ no upfront cost 10 18.5 13.9 Permittees w/ at least 10k upfront cost 21 38.9 29.2 NUMBER VESSELS CURRENTLY ABLE TO CARRY OBSERVER 38 70.4 52.8 IF AUC WERE OPENED, WOULD IT INFLUENCE DECISION TO FISH? Yes 18 33.3 25.0 No 30 55.6 41.7 Unknown 6 11.1 8.3 PLANS FOR PERMIT: Sell permit w/ boat 3 5.6 4.2 Sell permit 15 27.8 20.8 Keep permit 16 29.6 22.2 Transfer permit to friend/family 7 13.0 9.7 Unknown plans for permit 13 24.1 18.1 PFMC 03/12/14 5