Southeast U.S. Fisheries Bycatch Reduction Technology. John Mitchell NOAA Fisheries Southeast Fisheries Science Center Harvesting Systems Unit

Transcription

1 Southeast U.S. Fisheries Bycatch Reduction Technology John Mitchell NOAA Fisheries Southeast Fisheries Science Center Harvesting Systems Unit 1

2 Harvesting Systems Unit Working with industry to develop selective fishing gear - Trawl Gear - Pelagic longlines - Gill nets - Trap Gear Staff - Research biologists - Gear specialists - Divers 2

3 Harvesting Systems Unit Fishery-Dependent Research - At-sea testing and evaluation - Assess usability of new gear concepts - Evaluate effects on target catch 3

4 Harvesting Systems Unit Fishery-Independent research NOAA vessels Using technology to: - Evaluate gear dynamics - Understand fish and marine animal behavior relative to gear 4

5 Harvesting Systems Unit Fisher Training - Workshops - Gear distribution - At-sea assistance - Handbooks / Videos 5

6 Harvesting Systems Unit Marine Enforcement Training: methods of inspection - TEDs - BRDs - Pelagic longlines - Trap Gear 6

7 What is Bycatch? Definition is Relative to Stakeholder Fishing Community Discarded species and non-targeted species retained and sold. Fisheries Managers Discarded species as a result of economic or legal considerations Conservation Groups Waste Species and the catch of marine mammals and other high profile sea life 7

8 What is Bycatch? Fish which are harvested in a fishery, but which are not sold or kept for personal use, and includes economic discards and regulatory discards. Such term does not include fish released alive under a recreational catch and release management program Magnuson-Stevens Fishery Conservation and Management Act 8

9 What is Bycatch? Discarded catch of any living marine resource plus retained incidental catch and unobserved mortality due to direct encounter with fishing gear. NOAA Fisheries U.S. National Bycatch Report 9

10 What is Bycatch? Yesterday's bycatch may be today's target species. 10

11 Bycatch Reduction Technology Trawl Fisheries TARGET SPECIES Shrimp, Fish, Crabs, Molluscs POTENTIAL BYCATCH Juvenile, undersized or non-marketable shrimp and fish Sharks, Rays Sea Turtles 11

12 TRAWL VIDEO 12

13 THE ISSUE Sea turtles protected under the U.S. Endangered Species Act The incidental capture of sea turtles in trawls made illegal Southeast U.S. shrimp trawl fishery identified as primary cause of sea turtle mortality 6 species inhabit U.S. waters: Green Hawksbill Kemp's ridley Leatherback Loggerhead Olive ridley 13

14 Shrimp Fishery Fleet Characterization Gulf of Mexico & Atlantic : 1985 Offshore vessels = 6,000 Inshore vessels = 11,000 Total 17,000 * Fishery value (annual) : 230 million lbs. of product = U.S. $460 Million * Source: Shrimp Amendment 11 14

15 Turtle mortality estimate due to shrimp trawling (Henwood and Stuntz, 1987) Annual estimate Loggerhead = 9,874 Kemp s ridley = 767 Green turtles = 229 Total = 10,870* Catch rates significantly higher in SE Atlantic vs. Gulf of Mexico (16:1) * Estimate derived from offshore trips 15

16 Closure of fishing zones Time/Area restrictions Limit tow times Gear modifications to prevent captures Possible Management Measures to Prevent Sea Turtle Capture in Trawls 16

17 Turtle Barriers

18 Turtle Excluder Device (TED) Research and Development NMFS TED (1980) 18

19 Turtle Excluder Device (TED) Research and Development TED Effectiveness in reducing turtle captures demonstrated NMFS TED Turtle Reduction = 97% Shrimp reduction = % 19

20 Voluntary TED-use Voluntary adoption program initiated TEDs distributed to shrimpers for trials Shrimpers evaluations determined NMFS TED was too large and cumbersome. Reduction of turtle capture was not sufficient incentive for voluntary use by industry 20

21 Turtle Excluder Device (TED) Redesign (1982) Design modifications to improve acceptance Finfish Exclusion Smaller size Collapsible 1

22 Trawling Efficiency Device ( ) Daytime fish reduction = 70% Nighttime fish reduction = 53% Shrimp loss = % 2

23 Litigation and Regulation 1987 Final TED regulations published Ends voluntary TED use Strong industry opposition Industry develops new TED designs 3

24 Industry Involvement In TED Design Soft TED Georgia Jumper Super Shooter Weedless TED 4

25 Approving new TEDs Testing Protocol Controlled test using divers and conditioned turtles Leads to candidate TED certification and installation requirements Provides opportunity for industry to evaluate new ideas Improvements in TED performance for turtles and shrimp retention 5

26 TED Design Today 6

27 Protection of Sea Turtle with TEDs 97 to 100% exclusion of all sea turtle species captured in trawls Significant cause of mortality practically elimínated TED provides sea turtle protection with minimal impact to shrimp production TEDs must be installed correctly and routinely maintained 7

28 VIDEO TED 3 AVI 8

29 TED Update: Fish Trawls Quantify catch loss of target species associated with TED use in flynet gear Quantify catch loss of key bycatch species associated with TED use in flynet gear Identify handling problems or specialized handling techniques required when utilizing a TED in flynet gear 9

30 TED Update: Fish Trawls Be Flexible! 10

31 TED Update: Fish Trawls Results Total Catch (lbs/hr) Target Catch (lbs/hr) Bycatch (lbs/hr) Target spp n TED Control %Diff TED Control %Diff TED Control %Diff Croaker 23 3, , % 1, , %* 1, , % Menhaden 12 8, , % 8, , % % Bluefish % %

32 TED Update: Skimmer Trawls Currently TED exempt Potentially 2,400 additional TED users 12

33 TED Update: International TED use Section 609 of U.S. Public Law Shrimp imported into the U.S. must be harvested in ways that do not harm sea turtles 14 nations TED certified 13

34 Addressing Shrimp Trawl Bycatch 14

35 Shrimp Trawl Bycatch Shrimp to bycatch ratios variable by area, season and gear type 4:1 ratio average 10:1 ratio by areas and seasons In GOM, 70% of discards are scianids (croaker, spot, trout) 15

36 Regional Bycatch Program to Address Red Snapper bycatch Bycatch Reduction Device (BRD) 1990 to present research and development Over 200 BRD designs evaluated 1998, Amendment 9 Certification Criteria Reduce the bycatch mortality of juvenile red snapper by a minimum of 44% from the average level of mortality for the years Fisheye and Jones-Davis certified BRD performance monitoring, 1999-Present 16

37 2008 modifications to the BRD certification criterion Gulf and South Atlantic Demonstrate a 30% reduction in finfish by weight Provisional Certification BRDs demonstrating a 25% reduction in finfish (Provisional certification lasts 2 years) 17

38 Bycatch Reduction from Trawls Mechanical Sorting Possible when the bycatch species are larger than the target catch Example: Turtle Excluders (TEDs) are sorting grids used to direct large animals out of escape openings in trawls (sea turtles, sharks and rays) Behavioral Sorting When target and bycatch species are similar in size, rely on behavioral differences in target and bycatch species Finfish Bycatch Reduction Devices (BRDs) 18

39 Fisheye Codend Fisheye BRD 19

40 BRD Designs 20

41 1

42 Square Mesh Panels 2

43 Square Mesh Panel 3

44 Currently Certified BRDs Gulf of Mexico Evaluation BRD Type Percent Reduction in Total Finfish Bycatch by weight Shrimp loss percentage by weight Fisheye < 9' from tie-off rings (Gulf) BRD Type Jones Davis Modified Jones Davis Extended Funnel (s) Denotes statistically significant difference (p< 0.05) Composite Panel With Square mesh panel Composite Panel with cone

45 Comparative testing methods Covered codend method 5

46 Comparative testing methods Alternate haul method 6

47 Comparative testing methods Experimental gear Parallel haul method 7

48 Comparative testing methods Experimental gear Twin trawl method Standard gear (control) 8

49 Comparative testing methods Trouser trawl method Experimental Control 9

50 Direct Underwater Observations DIDSON / ARIS Sonar Acoustic camera / 3-D imaging The resolution, texture and detail make DIDSON images almost photographic in quality. DIDSON Video 10

51 Bycatch Reduction Technology Pelagic and Bottom Longline TARGET SPECIES Pelagic: Tuna, Swordfish, Mahi, Shark Bottom: Grouper, Snapper POTENTIAL BYCATCH Undersized target catch Sharks Sea Turtles, Marine Mammals 11

52 Longline Configuration Highflyer Floatline Mainline Gangion 12

53 Sea Turtle Bycatch Hard-shelled turtles mouth hooked Leatherback turtles generally entangled or foul hooked 13

54 Sea Turtle Bycatch Experiment Northeast Distant Waters Swordfish Fishery

55 Sea Turtle Bycatch Experiment NED Swordfish Fishery Bait Type: Fish vs. Squid Hook Type: J-hook vs. circle hook 15

56 Sea Turtle Bycatch Experiment Results Optimal Combination For Sea Turtle Mitigation Loggerhead Turtles Leatherback Turtles % Difference - 88% (reduction) - 63% (reduction) Mackerel bait 18/0 Circle Hook Swordfish + 20% (increase) Bigeye Tuna - 80% (reduction) Watson. et al Fishing methods to reduce sea turtle mortality associated with pelagic longlines. Can. J. Fish. Aquat. Sci. 62:

57 Evaluation of Injury Potential Loggerhead Sea Turtles Relating to Hook Size and Baiting Techniques Percent Attempt to Swallow Percentage of Turtles /0 16/0 18/0 20/0 Hook Size 45 CM SCL 55 CM SCL 65 CM SCL 17

58 Sea Turtle Deep Ingestion Rates Corresponding to Bait Type 40 Bait Types % Attempt to Swallow Squid Sardines 18

59 US Pelagic Longline Requirements Northeast Distant Area (NED) 18/0 or larger circle hook Whole mackerel or squid bait Atlantic and Gulf of Mexico areas 16/0 or larger circle hooks Whole fish or squid bait All Areas Use of safe turtle handling and release gear 19

60 Safe Turtle Handling and Release Gear 20

61 Problem Weak Hooks: Reducing Bluefin Tuna Bycatch in the Gulf of Mexico Yellowfin Tuna Fishery The GOM is a major spawning area for the western Atlantic bluefin tuna stock. Concern due to the bycatch mortality of spawning bluefin tuna in the directed yellowfin tuna longline fishery. 1

62 Background Anecdotal information indicated that spawning bluefin tuna, which are much larger than yellowfin tuna, are capable of straightening some hook types used in the yellowfin fishery. 2

63 Experimental Gangion Float Float Line Main Line 2 fath. 400# 250# 2 fath. 1 fath. 2 fath. 400# 200# 1 fath. 2 fath. 400# 140# 1 fath. Experimental Gangion Configuration 8 fath. 45 gr. 2 fath. 3

64 Experimental Design Gear Configuration Control Control Control Control Control Treatment Treatment Treatment Treatment Treatment Control: Standard 16/0 Mustad Carbon Steel Circle Hook w/sardine bait Treatment : Custom 16/0 Mustad Circle Hook Constructed of 15/0 Carbon Steel Material w/sardine bait Hook timers and depth recorders used to characterize duration bluefin bite/release event 4

65 Weak Hook Experiment Results 8 commercial vessels involved in tests 418 pelagic longline sets completed 134 bluefin were caught during the experiment 47 caught on the experimental hook 46% reduction in bluefin with weak hooks 2,547 yellowfin tuna landed 6% reduction in yellowfin catch (ns) Majority of bluefin escapes took place in < 5 min. 5

66 Hook Bending No effect YFT YFT YFT Unknown 6

67 Weak Hook Regulatory Action May 5, 2011 All vessels fishing for highly migratory species (HMS) in the Gulf of Mexico with pelagic longline (PLL) gear onboard must: Possess, use, and deploy only circle hooks that are described at Title 50 of the U.S. Code of Federal Regulation (CFR) (c), and that are constructed of corrodible round wire stock that is no larger than 3.65 mm in diameter. 7

68 Green-Stick Fishing for Tuna Source: NC Sportsman Magazine 8

69 Green-Stick Pole (10-14 m) Bird Artificial Bait 9

70 Green-Stick Bait spends majority of the time out of the water Bird 10

71 Greenstick and Tuna Quality Green-stick gear has been used along the Atlantic coast for several years (concentrated in NC) Potential for having low bycatch and bycatch mortality compared to PLL May be viable alternative to PLL in some areas Tunas caught on green-stick gear sometimes grade lower than tunas caught on PLL gear 11

72 Fixed Gear Fisheries Atlantic Large Whale Take Reduction Plan (ALWTRP) Gillnets Traps / Pots 12

73 Regulated trap/pot Areas 13

74 Weak Links for Buoy, Flotation or Weighted Devices 14

75 All groundlines must be made of sinking line. 15

76 Conclusions Effective Implementation of Bycatch Reduction Technologies Selective fishing technology must demonstrate an economic benefit to fishers to be effectively adopted. Dedicated technology transfer 16

77 Conclusions Effective Implementation of Bycatch Reduction Technologies Adoption of laws requiring bycatch technology. Regular monitoring by trained personnel. Legal framework capable of processing violators with appropriate fines. 17

78 Conclusions Effective Implementation of Bycatch Reduction Technologies Maintain dialog between Fishers, Managers and Enforcement 18

79 Thank You 19