2. Engineering Bycatch Reduction in West Indian Fish Traps: STFA CRP Trap Vent Study CRP Project No. NMF4540101

3. Prior Escape Vent Studies Source Vent Height (inches) Vent Width (inches) Trap Mesh Size Fish/ Trap Haul (Control Traps) Munro (1999) 2.761.101 inch10.0 3.151.18 3.541.30 3.540.98 Johnson (2010) 7.870.981 inch11.8 15. 3/4 0.98 STFA Pilot (2008) 612 Inch4.65 41 42 STFA CRP (2010) 61 3/4 2 Inch5.44 5 3/4 1 1/2 5 3/4 1 18.01 5 3/4 1 3/8 9 3/4 1 3/8 5 3/4 1 1/4 Olsen, Dammann and Laplace (1978) 1 inch32.8 1 by 2 inch17.5 1.5 Inch1.8

4. 1 by 16 inch Edge 1 by 5 3/4 inch Vent 1.5 by 5 3/4 inch Vent 1 3/4 by 5 ¾ inch Vent 1 3/8 by 9 3/4 inch Vent 1 3/8 by 5 3/4 inch Vent 1 3/8 by 5 3/4 inch Vent Escape Vents Tested

5. Summary of Trap Hauls Diving StudiesField Testing Vent Type Initial Dive Initial Haul Trap Stock- ing Phase 1 Phase 2 Phase 3 Phase 4 Control54624630148164100 1 by 5 3/4 Vent68765246148164 1 in Edge68765243-- 1 1/2 by 5 3/4 Vent68765241148164 1 3/4 by 5 3/4 Vent68765245- 1 3/8 by 5 3/4 Vent----148164400* 1 3/8 by 9 3/4 Vent----148164 Total322366254205740820500 * Located top and bottom front and back of the traps.

6. Video Studies 24 hour videos from 8 days (Renchen, 2010) Only daylight hours were used in order to be able to identify fish species and positions.* Position of fish in trap recorded every 5 minutes. In vent position study, 9 vents were placed in two strings of 10 baited traps. Vents were closed following final daily observations. Each trap was observed for 20 minutes and all escapes recorded. Video was recorded for one trap each day. Renchen reported that peak ingress/egress was around noon and occurred almost entirely during daylight hours.

7. Video Studies

8. Video Summary Results

11. St. Thomas St. John

12. Vent Choice Results A total of 28 escapes were observed or caught on video. Most escapement involved back vents (74%). Most escapement involved upper vents (70%). Results were used to guide design of Phase 4 field testing.

13. Experimental Design (Diving Studies) 1.Each trap string inspected by diving (species counts). 2.Estimate fish required for stocking. 3.Haul non-experimental traps to collect fish necessary to supplement for stocking. 4.Haul experimental traps, measure (TL) all fish and examine for fin clips. 5.Stock traps with fish from experimental and non- experimental traps that have been fin clipped. 6.Traps set for 1, 3, 5, 7 days before being revisited.

14. Changes in Numbers During Trap Hauling (Initial Dive vs Initial Haul) % of Trap Hauls

15. Species Escapement During Hauling (Most Common Species) Species Name Initial Dive Escaped During Initial Haul % Escape BUTTERFLYFISH,BANDED 25 832% PORGY,SAUCEREYE 10 330% GRUNT,BLUE STRIPED 119 2319% PARROTFISH,STOPLIGHT 21 419% BLUE TANG 189 2614% COWFISH,HONEYCOMB 21 314% SCHOOL MASTER 77 912% COWFISH,SCRAWLED 56 611% DOCTORFISH 9 111% HIND,RED 57 59% GRUNT,WHITE 51 48% TRIGGERFISH,QUEEN 16 16% LOBSTER,CARIB. SPINY 38 13% TRUNKFISH,SMOOTH 32 13% ANGELFISH,GRAY 29 13% TRUNKFISH,SPOTTED 19 -0% PORGY,PLUMA 14 -0% ANGELFISH,QUEEN 10 -0% Total for all species89210111%

16. Retention of Fin Clipped Fish

17. Retention of Fin Clipped Fish in Trap Retention of Fin Clipped Fish in Trap Hauls

18. Summary Larger fish were found in in longer sets (p<.06) 40-80% of the stocked fish left during the first day. Highest escapement was in traps with the widest vents. For all vent sizes most (90-100%) of the stocked fish were gone within 7 days. Larger vents sizes had faster exit rates. No species-specific tendencies were observed in exit although the larger vent sizes exhibited significant changes in species composition at all set lengths.

19. Experimental Design Standard St. Thomas Fish Traps – Rectangular and Arrowhead Design. – Set in Strings of 10 – Fishermen told to “fish them like they normally do” during field testing. Vents (2 per trap on the away from the funnel “front” side) – Control (no vent) – 1 by 5 3/4 inch vent – 1 inch vent along entire (18 inch) edge of trap – 1 1/4 by 5 3/4 inch Vent – 1 1/4 by 9 3/4 inch Vent – 1 3/8 by 5 3/4 inch Vent – 1 1/2 by 5 3/4 inch Vent – 1 3/4 by 5 3/4 inch Vent – Vents in Random order on trap string

20. Field Testing Series 1.Phase 1 field testing with vents from diving studies. 2.Phase 2 Field testing. 1 by 5 3/4, 1 3/8 by 5 3/4, 1 3/8 by 9 3/4, 1 1/2 by 5 3/4 and control traps. 3.Phase 3 testing. 1 by 5 3/4, 1 3/8 by 5 3/4, 1 1/4 by 5 3/4 (top of trap), 1 1/4 by 5 3/4 (bottom of trap) and control traps. 4.Phase 4 testing. 1 3/8 by 5 3/4 placed on the front and back top and bottom to test for vent location.

22. Study Catch Characterization (94 species) Category# Caught% Commercial Catch8,56262.7% Bycatch5,09937.3% Ciguatera60011.8% Non Commercial1462.8% Regulatory230.5% Too Small4,33084.9% Boxfish2,35354.3% Not Boxfish1,97745.7%

23. Field Testing Summary Results: General – Average Catch/Trap Haul does not stabilize until > 40 trap hauls. – No difference between rectangular and arrowhead traps – Catch/trap haul not correlated with set length. – Catch/trap haul not correlated with temperature. – Lunar affects (catches greater and fewer empty traps around full moon). – Seasonal peaks for most species. – Lionfish from 0 to 19 th most common species at end of study. – Mortality rate (0.031fish/day ) similar to diving studies and Renchen (2010) study (0.025fish/day ).

24. Cumulative Average # Fish/Trap Haul (Control Traps)

25. Species Seasonality of CPUE

26. Gear Selectivity

27. Selectivity Analysis: Fish Traps

28. Summary of Fish Life History Results Sample Size Species Measure- ment L first reproduction Female L first reproduction Male (mm) Min Catch (mm) MidPoint Overlap Min Catch and Max By catch (mm) % Above L first repro- duction Average Size Retained as Catch Size at 50% Recruit- ment to Fishing Gear Size at Full Recruit- ment 57Pomacanthus paruTL22626819220237%271.2164.5250-280 417Pomacanthus arcuatusTL22024018419362%256.5159.4200 135Holacanthus ciliarisTL170242 266.6209.4260 2120Acanthurus coeruleusFL130110173221100%244.1159.5200 262Chaetodon striatusTL133100%120.4130 168Epinephelus fulvusTL160220 281.4265.6280 674Lactophrys poligoniusTL165223 267.0185.3220 1356 Lactophrys quadricornus TL170160162211100%258.0184.0210 843Acanthurus chirurgusFL170140210213100%244.6208.6240 535Haemulon sciurusFL170-200140210100%280.9250.7290 27 Haemulon carbonarium FL224 264.9 28 Haemulon flavolineatum FL160204100%267.4 1020Haemulon plumieriFL130-150153216100%274.5244.9.5270

29. Sample Size Species Measure- ment L first reproduction Female L first reproduction Male (mm) Min Catch (mm) MidPoint Overlap Min Catch and Max By catch (mm) % Above L first repro- duction Average Size Retained as Catch Size at 50% Recruit- ment to Fishing Gear Size at Full Recruit- ment 1078 Epinephelus guttatus TL25021422194%321.4279.4300 110Pterois volitansTL 256.1310 296 Sparisoma chrysopterum FL240 303.5278.2310 414Sparisoma virideFL180160-200222100%312.9259.9320 564Calamus calamusFL200 266.7217.3250 513Lutjanus apodusFL250225 272.6290 25 Lutjanus buccanella FL230-260250-2702525628%284.6276.5 204Lutjanus synagrisFL180-235150-214248100%290.4278.1270 54Lutjanus analisFL41038030058%411.5259.3 Ocyurus chrysurus FL224188 156TrapsFL 230100%307.5271.8290 1973HandlineFL 21092%329.8278.1300 182SeineFL 20096%320.1270 1337Panulirus argusCL 89 81.7100 885Holocentrus rufusFL135208100%281.0273230 1610Balistes vetulaTL23526522323696%384.3218.5280 953 Lactrophry triqueter TL258 131.6180 264 Lactrophrys bicaudalis TL200219 275.6150.9200 Summary of Fish Life History Results

30. Total Mortality Rate The annual total mortality rate (shown in equation 5

31. Species Mortality Values Species# L max TL (in mm) Information from FISHBASE Current Analysis k LocationTotal Z Epinephelus cruentatus1683883400.23-5.3USVI1.025 Lutjanus synagris2043854500.23 Puerto Rico0.956 Sparisoma chrysopterum2963854180.78 BVI1.988 Sparisoma viridae4204022900.96 USVI0.567 Lutjanus apodus5636053490.35 USVI0.351 Haemulon Sciurus3153373710.3 Puerto Rico0.543 Acanthurus chirurgus8433183320.13 USVI0.517 Haemulon plumieri8793884200.26 Puerto Rico2.727 Epinephelus guttatus1,3564855680.12 St. John1.037 Balistes vetula1,4836496000.23 USVI0.966 Acanthurus coerulus2,1164143690.11 USVI0.374 Ocyurus chrusurus (Handline)1,8746305020.139-0.96Puerto Rico0.120 Ocyurus chrusurus (Traps)2306305020.139-0.96Puerto Rico0.093 Panulirus argus1,3371801520.432-.11 St. John0.472

32. Field Testing Summary Results: Vents Box fish. Only 2 by 4 and 1 3/4 by 5 3/4 vents let out boxfish and these also had very low retention of commercial catch. Study then concentrated on release of thin bodied not-box fish (TBNBF). Vent height. – 1 inch by 18 had significant release of TBNBF and retention of commercial species. – 1 by 4 released significantly less TBNBF than 1 by 6 in pilot study. – 1 3/8 by 9 3/4 Vent did not release more TBNBF than 1 3/8 by 5 3/4. Vent Width. 1 1/4 by 5 3/4 and 1 3/8 by 5 3/4 both has good release of TBNBF and retention of catch but 1 3/8 by 5 3/4 had better release of bycatch. Vent Location. Top and bottom not significant but vents in front (away from funnel) side had significantly higher release rates. (Contrasts with diving observations).

34. Impact of Selected Vents Control1 3/8 VentsComparison SpeciesCountAvg. TL CountAvg. TL Control CPUE Vent CPUE Reduction % Reduc- tion Control CPUE % Control TL Acanthurus coeruleus311192.7775200.090.7550.1820.57381%103.8% Acanthurus chirurgus135232.4792239.150.3280.2230.10445%102.9% Balistes vetula295368.42258380.390.7160.6260.09030%103.3% Calamus calamus62266.8225279.080.1500.0610.09068%104.6% Pomacanthus arcuatus43225.2633262.910.1040.0800.02438%116.7% Holacanthus ciliaris15234.272205.000.0360.0050.03289%87.5% Holacanthus tricolor22185.508186.290.0530.0190.03471%100.4% Chaetodon striatus27124.339125.780.0660.0220.04473%101.2% Sparisoma chrysopterum55304.3632307.630.1330.0780.05653%101.1% Sparisoma viride55308.8955324.640.133 0.00020%105.1% Lutjanus apodus59319.0039321.640.1430.0950.04947%100.8% Holocentrus rufus135283.16135285.230.328 0.00020%100.7% Lutjanus synagris19285.9517287.530.0460.0410.00528%100.6% Lutjanus buccanella17283.713311.330.0410.0070.03486%109.7% Ocyurus chrysurus13347.6928364.390.0320.068-0.036-73%104.8% Haemulon plumieri109278.40106280.000.2650.2570.00722%100.6% Haemulon sciurus55285.1869284.100.1330.167-0.034-1%99.6% Epinephelus fulvus25284.5632278.250.0610.078-0.017-3%97.8% Epinephelus guttatus148321.09169324.960.3590.410-0.0518%101.2% Pterois volitans22267.8225282.360.0530.061-0.0079%105.4% Haemulon melanurum17271.004259.250.0410.0100.03281%95.7% Lactophrys quadricornis197224.89273217.190.4780.663-0.184-12%96.6% Lactophrys triqueter126168.40184168.820.3060.447-0.141-18%100.3% Lactophrys bicaudalis24212.7931207.390.0580.075-0.017-4%97.5% Lactophrys poligonius74237.45127232.700.1800.308-0.129-38%98.0%

35. Impacts of 1 3/8 Vents on Selected Species Species L first repro- duction Female L first repro- duction Male Size at 50% Recruit- ment to Gear Min Catch % Above L first repro- duction % Reduct- ion from Control CPUE % Increase in TL Acanthurus coeruleus 130110159.5173100%81%4% Acanthurus chirurgus 170140208.6210100%45%3% Sparisoma chrysopterum 278.2240 53%1% Sparisoma viride 180160-200259.9222100%20%5% Pomacanthus arcuatus 220240159.418462%38%17% Holacanthus ciliaris 209.4170 89%1% Chaetodon striatus 120.4133 73%1% Calamus calamus 217.3200 68%5% Balistes vetula 235265218.5.422396%30%3%

36. Implementation Fishermen from Phase 4 of study are leaving vents in. (Julian Magras, Daryl Bryan, Tony Blanchard and Danny Berry) Proposal to Bycatch Reduction Program. – Fishermen install vents in one string. – Port Sample vent string and one regular string. – If convinced project to supply vents for remainder of traps. Council/Territorial Regulation.