HIGHLY MIGRATORY SPECIES MANAGEMENT TEAM REPORT ON DRIFT GILLNET MONITORING, MANAGEMENT, AND ALTERNATIVE GEAR REPORT

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1 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 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, Observed Leatherback and Swordfish BPUE/CPUE Ratio by Area and Season, Closed Season, AUC (Aug 15-Nov 15) Open Season, AUC (Nov 16-Jan 31) Non-PLCA Observed Effort (Sets) Swordfish Catch (Counts) Swordfish CPUE Leatherback Takes (Counts) Leatherback BPUE Leatherback-Swordfish BPUE/CPUE Observer coverage of drift gillnet effort from 1990 to 2000 was 16.4% of the total number of sets fished over the period. 1

2 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 AUC: Closed Season (Aug 15-Nov 15) AUC: Open Season (Nov 16-Jan 31) Outside PLCA 6.0 CPUE 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 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

3 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 Post 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 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

4 Appendix 1. Summary of Potential Effort, Revenue, Finfish and Protected Species Impacts Closed Season, AUC Open Season, AUC Non-PLCA Low Effort Revenues ($1000s) $28.0 $5.1 $677.9 Swordfish Common Thresher Shark Shortfin Mako Shark Blue Shark Albacore Tuna Bluefin Tuna Yellowfin Tuna Bigeye Tuna Skipjack Tuna Dorado Striped Marlin Leatherback Turtle Loggerhead Turtle Humpback Whale Sperm Whale Mola Mola , Pelagic Thresher Shark Bigeye Thresher Shark White Shark Megamouth Shark Basking Shark Medium Effort Revenues ($1000s) $35.7 $5.1 $902.2 Swordfish Common Thresher Shark Shortfin Mako Shark Blue Shark Albacore Tuna Bluefin Tuna Yellowfin Tuna Bigeye Tuna Skipjack Tuna Dorado Striped Marlin Leatherback Turtle Loggerhead Turtle Humpback Whale Sperm Whale Mola Mola , Pelagic Thresher Shark Bigeye Thresher Shark White Shark Megamouth Shark Basking Shark High Effort Revenues ($1000s) $45.9 $7.6 $1,129.0 Swordfish Common Thresher Shark Shortfin Mako Shark Blue Shark , Albacore Tuna Bluefin Tuna Yellowfin Tuna Bigeye Tuna Skipjack Tuna Dorado Striped Marlin Leatherback Turtle Loggerhead Turtle Humpback Whale Sperm Whale Mola Mola , Pelagic Thresher Shark Bigeye Thresher Shark White Shark Megamouth Shark Basking Shark

5 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 AVERAGE NUMBER OF YEARS PERMIT HELD 22 NUMBER PERMITS ACTIVE W/IN LAST 5 SEASONS NUMBER PERMITTEES ACTIVE IN OTHER FISHERIES DGN FISHING SEASON: Plan to fish Do not plan to fish May possibly fish Unknown if will fish NUMBER WITH RESOURCES TO FISH DGN SEASON AVERAGE DAYS OF PREPARATION TO FISH DGN (n=49) 28 AVERAGE COST OF PREPARATION TO FISH DGN (n=47) $18,798 Permittees w/ no upfront cost Permittees w/ at least 10k upfront cost NUMBER VESSELS CURRENTLY ABLE TO CARRY OBSERVER IF AUC WERE OPENED, WOULD IT INFLUENCE DECISION TO FISH? Yes No Unknown PLANS FOR PERMIT: Sell permit w/ boat Sell permit Keep permit Transfer permit to friend/family Unknown plans for permit PFMC 03/12/14 5