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Implementing Trap Vents CFMC has provided $5,000 This will purchase 6,250 Vents for 3,125 Traps. randomization test reference: Manly , B. F. J. 2006. Randomization, Bootstrap and Monte Carlo Methods in Biology, 3rd Edition. Chapman and Hall/CRC. . Impact of CFMC Vents. - PowerPoint PPT Presentation
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Implementing Trap Vents
CFMC has provided $5,000This will purchase 6,250 Vents
for 3,125 Traps
Species Control CPUE Vent CPUE Reduction% Reduction from Control
CPUEHolacanthus ciliaris 0.036 0.005 0.032 89%
Acanthurus coeruleus 0.755 0.182 0.573 81%
Haemulon melanurum 0.041 0.01 0.032 81%
Chaetodon striatus 0.066 0.022 0.044 73%
Holacanthus tricolor 0.053 0.019 0.034 71%Calamus calamus 0.15 0.061 0.09 68%
Sparisoma chrysopterum 0.133 0.078 0.056 53%
Lutjanus apodus 0.143 0.095 0.049 47%
Acanthurus chirurgus 0.328 0.223 0.104 45%
Pomacanthus arcuatus 0.104 0.080 0.024 38%
Balistes vetula 0.716 0.626 0.09 30%
Lutjanus synagris 0.046 0.041 0.005 28%
Haemulon plumieri 0.265 0.257 0.007 22%
Holocentrus rufus 0.328 0.328 0 0%
Sparisoma viride 0.133 0.133 0 0%Pterois volitans 0.053 0.061 -0.007 -9%
Epinephelus guttatus 0.359 0.41 -0.051 -8%
Haemulon sciurus 0.133 0.167 -0.034 -1%
Epinephelus fulvus 0.061 0.078 -0.017 -3%
Lactophrys bicaudalis 0.058 0.075 -0.017 -4%
Lactophrys quadricornis 0.478 0.663 -0.184 -12%
Lactophrys triqueter 0.306 0.447 -0.141 -18%
Lactophrys poligonius 0.18 0.308 -0.129 -38%
Ocyurus chrysurus 0.032 0.068 -0.036 -73%
Species Reduction in CPUE
TL Increase
Acanthurus bahianus 90% 10%
Cantherhines pullus 90% 28%
Holocanthus ciliaris 89% 14%
Acanthurus coeruleus 81% 4%
Chaetodon striatus 73% 1%
Calamus calamus 68% 5%
Sparisoma chrysopterum 53% 1%
Acanthurus chirurgus 45% 3%
Pomacanthus arcuatus 38% 17%
Cantherhines macrocerus 54% 20%
Balistes vetula 30% 3%
Aluterus schoepfi 19% 6%
Size Class200 250 300 350 400 450 500 550
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Red Hind (Epinephelus guttatus) N.S.
Size Class150 200 250 300 350 400 450
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
White Grunt (Haemulon plumieri) N.S.
Size Class
100 200 300 400 500
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Redfin Parrotfish (Sparisoma rubripinne) N.S.
Size Class100 150 200 250 300 350 400 450 500
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Queen Triggerfish (Balistes vetula) P < 0.05
Size Class100 200 300 400
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Saucereye Porgy (Calamus calamus) P < 0.001
Size Class100 150 200 250 300 350 400 450
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Gray Angelfish (Pomacanthus arcuatus) P < 0.001
Size Class200 250 300 350 400 450
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Stoplight Parrotfish (Sparisoma viride) P < 0.001
Size Class
160 180 200 220 240 260 280 300 320 340 360
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Doctorfish (Acanthurus chirurgus) P < 0.001
Size Class100 150 200 250 300 350
Selectivity
0.0
0.2
0.4
0.6
0.8
1.0
Control Observed Control Predicted Treatment Observed Treatment Predicted
Blue Tang (Acanthurus coeruleus) P < 0.001
randomization test reference: Manly, B. F. J. 2006. Randomization, Bootstrap and Monte Carlo Methods in Biology, 3rd Edition. Chapman and Hall/CRC.
Traps 3,125 Set Length
(dys) 9.7
Hauls/Year 38 # Trap Hauls 118,750
Impact of CFMC Vents
SpeciesControl CPUE Vent CPUE
% Reduc-tion
Control CPUE
Catch without
VentsCatch with
VentsReduction/Increase
Holacanthus ciliaris 0.036 0.005 86% 4,275 3,681 594Lutjanus buccanella 0.041 0.007 83% 4,869 4,038 831
Acanthurus coeruleus 0.755 0.182 76% 89,656 68,044 21,613Haemulon melanurum 0.041 0.01 76% 4,869 3,681 1,188
Chaetodon striatus 0.066 0.022 67% 7,838 5,225 2,613Holacanthus tricolor 0.053 0.019 64% 6,294 4,038 2,256
Calamus calamus 0.15 0.061 59% 17,813 10,569 7,244Sparisoma chrysopterum 0.133 0.078 41% 15,794 6,531 9,263
Lutjanus apodus 0.143 0.095 34% 16,981 5,700 11,281Acanthurus chirurgus 0.328 0.223 32% 38,950 12,469 26,481
Pomacanthus arcuatus 0.104 0.08 23% 12,350 2,850 9,500Balistes vetula 0.716 0.626 13% 85,025 10,688 74,338
Lutjanus synagris 0.046 0.041 11% 5,463 594 4,869Haemulon plumieri 0.265 0.257 3% 31,469 950 30,519Holocentrus rufus 0.328 0.328 0% 38,950 38,950 0Sparisoma viride 0.133 0.133 0% 15,794 15,794 0
Epinephelus guttatus 0.359 0.41 -14% 42,631 48,688 -6,056Pterois volitans 0.053 0.061 -15% 6,294 7,244 -950
Haemulon sciurus 0.133 0.167 -26% 15,794 19,831 -4,038Epinephelus fulvus 0.061 0.078 -28% 7,244 9,263 -2,019Ocyurus chrysurus 0.032 0.068 -113% 3,800 8,075 -4,275
Total 472,150 268,900 202,590(Releases
only)
STFA/SCCFA Spiny Lobster Project
Second Progress Report 3/26/2013
Tagging and MeasuringFloy “Spaghetti” Tags
Measure with calipers to the
nearest 1 mm CL
Inject tag between the tail
and end of carapace
Check tag security
Trip SummaryIsland Month # Trips #
Measured # Tagged Project Recaptures
Non Project Recaptures # Kept
St. Croix September 2012 10 236 236 0 St. Croix October 2012 40 601 577 4 3 St. Croix November 2012 25 374 356 15 3St. Croix December 2012 6 107 104 3 4 St. Croix January 2013 3 19 15 4 St. Croix February 2013 1 2
St. Croix Total 84 1337 1288 27 9 3
St. Thomas September 2012 12 633 494 6 1 2St. Thomas October 2012 28 1012 776 15 1 1St. Thomas November 2012 18 338 323 16 2 4St. Thomas December 2012 21 576 310 29 2 12St. Thomas January 2013 13 302 276 26 2 9St. Thomas February 2013 11 293 275 18 3 7St. Thomas March 2013 13 316 249 15 1 1
St. Thomas Total 112 3470 2703 127 12 36
% of Lobster by CL (Complete Trips)
0%
5%
10%
15%
20%
25%
30%
35%
ST. CroixSt. Thomas
CV for Average Carapace Length
0 200 400 600 800 1000 1200 14000.0
2.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
St.X CV
STT CV
# Lobsters
CV
0 2 4 6 8 10 12 140
20
40
60
80
100
120
140
160
180
200
Olsen StudyCuban Study
Age (yrs)
Cara
pace
Leng
th (m
m)
Parameter St. Thomas Cuba Study𝐿∞ 150mm 195mm ~214mmk 0.432 0.24 𝑡0 0.11 0.46
Lobster Growth STT and Cuba
(𝐿∞=𝐿∞ (1−𝑒(−𝑘(𝑡−𝑡0)))
Recaptures (Days at Large)
0 10 20 30 40 50 60 70 80 90 100 110 120 130 1400
5
10
15
20
25
30
35
# Days at Large
Mortality Calculation• Von Bertalanffy growth equation . • Solve for (t) for carapace length. • This provides the age for each size class in the size frequency
distribution so that total mortality (Z)
Where: is the number of lobsters at time (t) and (t-1)andZ is the rate of total mortality.
can be calculated as the difference in numbers from the size class bin at full recruitment and the size class bin containing L
50 60 70 80 90100
110120
130140
150160
170180
0
20
40
60
80
100
120
140
160
Carapace Length (mm)
Freq
uenc
y
Full Recruitment (N=137)
L∞ N=1
Z=0.316
St. Thomas Complete Trips
7.1 Years
45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 1500
20
40
60
80
100
120
Carapace Length (mm)
# Lo
bste
rs
Full Recruitment (N=112)
Lfinal N=2
Z=0.959
St. Croix Complete Trips
2.4 Years
Total Mortality (Z) Calculated from TIP Data
19711981
19831985
19871989
19911993
19951997
19992001
20032005
20072009
2011
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
St. Thomas Moving average (St. Thomas)
St. Croix Moving average (St. Croix)
Tota
l Ann
ual M
orta
lity
(Z)
01224364860728496108120132144156168180
0 1224 3648 6072 8496 108120 132144 156168 180
Fishing mortality rate
Size
at fi
rst c
aptu
re (m
m ca
rapa
ce le
ngth
)
St. Thomas St. Croix
Yield Per Recruit
Population Analysis
• Review of CCR data showed that following 1997, the data for total traps owned was input instead of daily trap hauls.
• Only affects fishermen hauling more than one day per week (i.e. bigger fishermen).
• Interviewed all fishermen showing “unreasonable” daily trap haul numbers.
• Multiplied interview results by number of trips to obtain adjusted trap haul values.
Comparison Between Annual Trap Hauls andCCR Reports and Fishermen Interviews
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 20070
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
450,000
500,000
CCR Reports Fishermen Interviews
Year
Tota
l Ann
ual T
rap
Hau
ls
19911992
19931994
19951996
19971998
19992000
20012002
20032004
20052006
0.00
0.20
0.40
0.60
0.80
1.00
1.20
1.40
Adjusted EffortCCR Effort
Annu
al C
PUE
(lbs/
trap
hau
l)
SEFCS Supplied Value
Comparison of CPUE
From: [email protected]: [email protected]: [email protected], [email protected], [email protected]: 2/12/2013 10:00:32 A.M. Paraguay Standard TimeSubj: Re: Fishermen Trap Haul Survey
Dear David
We have been asked by the VI DFW to have all requests for VI data routed through them so that they can be aware of all requests for their data and to respond to those requests if it is within their capability. Therefore would you please forward your requests to the chief fisheries scientists at DFW. The SEFSC Fisheries Statistics Division is be willing to assist the VI DFW with meeting such requests where we have capabilities for extracting information which they might not have.
Regards
Steve Turner Chief, Fisheries Statistics Division
Monthly Landings: St. Thomas
January
February
March AprilMay
JuneJuly
August
September
October
N ovember
December
0%
2%
4%
6%
8%
10%
12%
14%
16% 1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2006
2005
Average
Monthly Landings: St. Croix
0%
2%
4%
6%
8%
10%
12%
14%
16%
18%
20%
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
Average
Population EstimationSt. Thomas Average Landings
# Lobsters
Cum # Tagged
% Tagged
% Recap- tured
# Recap- tured
Estimated Pop Size
September 7.3% 9,468 4,051 492 12.1% 0.17% 7 284,759
October 8.2% 10,650 4,557 1269 27.8% 0.35% 16 361,421
November 8.6% 11,132 4,763 1589 33.4% 0.38% 18 420,510
December 10.7% 13,800 5,905 1891 32.0% 0.52% 31 360,202
January 10.6% 13,680 5,854 2170 37.1% 0.48% 28 453,665
February 9.2% 11,859 5,074 2466 48.4% 0.43% 22 564,171
March 9.4% 12,191 5,217 2700 51.8% 0.33% 17 828,527
2010 Landings 129,471
2010 Average weight
1061 2.34 lbs
St. Croix Average Landings#
LobstersCum # Tagged
% Tagged
% Recap-tured
# Recap-tured
Estimated Pop Size
September 9.2% 11,974 5,124 236 4.6% 0.00% 0
October 8.0% 10,414 4,456 813 18.2% 0.16% 7 517,526
November 8.5% 10,949 4,685 1166 24.9% 0.32% 15 364,194
December 8.1% 10,441 4,468 1273 28.5% 0.16% 7 812,470
January 9.1% 11,742 5,025 1288 25.6% 0.08% 4 1,617,897
February 8.0% 10,386 4,444 1288 29.0% 0.07% 3 1,907,931
2010 Landings 134,501
2010 Average weight
1015 2.24 lbs
Virgin Islands Spiny Lobster Landings
19741976
19781980
19821984
19861988
19901992
19941996
19982000
20022004
20062008
20100
20,000
40,000
60,000
80,000
100,000
120,000
140,000
160,000
St. Croix ACL= 107,000 lbsSt. Thomas/St. John ACL= 104,000 lbs
Year
Land
ings
(lbs
)
Island Differences in Methods2006 CCR Data
Island Diving Traps
St. Thomas/St. John 15.9% 97.6%
St. Croix 84.1% 2.4%
Average sizes are significantly different betweenIslands (F= 102.7, p<0.001)
Difference between size of Trap and SCUBA caught lobsters on St. Croix not significant (F=0.76, p=0.38)
Island Differences in SizesCFMC Project Complete Trips
Island Average CL
St. Thomas/St. John 101.9 mm
St. Croix 91.9 mm
Lobster Assessments
Evidence/Data• Catch by gear.• CPUE-based abundance indices (calculated from
summary data due to lack of access).• Size distribution of catches.Analysis• Statistical estimation of initial population size,
recruitment history, and fishing mortality rates by fitting catch, CPUE, and size data.
Assessment Details
Drivers of this assessment model:• Size data and catch-CPUE data series give two pictures
of fishing mortality rates and recruitment strength.• Potential for conflict between these two datasets.Recruitment• No attempt at fitting a stock-recruitment relationship
within the model.• Instead, this relationship can be evaluated after the
fact.
1970 1975 1980 1985 1990 1995 2000 2005 20100
10000
20000
30000
40000
50000
60000
70000
80000
STT Trap LandingsObserved LandingsPredicted Landings
Year
Land
ings
(kg)
1970 1975 1980 1985 1990 1995 2000 2005 20100
1000
2000
3000
4000
5000
6000
STT Diver LandingsObserved LandingsPredicted Landings
Year
Land
ings
(kg)
1970 1975 1980 1985 1990 1995 2000 2005 20100
0.51
1.52
2.53
3.54
4.55
STT Trap IndexObserved IndicesPredicted Indices
Year
Stan
dard
ized
CPUE
1970 1975 1980 1985 1990 1995 2000 2005 20100
0.5
1
1.5
2
2.5
STT Diver IndexObserved IndicesPredicted Indices
Year
Stan
dard
ized
CPUE
1970 1975 1980 1985 1990 1995 2000 2005 20100
2000
4000
6000
8000
10000
12000
14000
STX Trap LandingsObserved Land-ings
Year
Land
ings
(kg)
1970 1975 1980 1985 1990 1995 2000 2005 20100
10000
20000
30000
40000
50000
60000
70000
80000
STX Diver LandingsObserved Land-ings
Year
Land
ings
(kg)
1970 1975 1980 1985 1990 1995 2000 2005 20100
0.5
1
1.5
2
2.5 STX Trap IndexObserved IndicesPredicted Indices
Year
Stan
dard
ized
CPUE
1970 1975 1980 1985 1990 1995 2000 2005 20100
0.5
1
1.5
2
2.5
3
STX Diver IndexObserved IndicesPredicted Indices
Year
Stan
dard
ized
CPUE
1970 1975 1980 1985 1990 1995 2000 2005 2010 201590
95
100
105
110
115
120St. Thomas/St. John Average Carapace Length
TIP Data
Olsen 1971 Study
Cara
pace
Leng
th (m
m)
1980 1985 1990 1995 2000 2005 2010 201598
100
102
104
106
108
110
112
114
St. Croix Spiny Lobster CLCa
rapa
ce Le
ngth
(mm
)
Draft Results
• St. Thomas-St. John—conflict between two sources of information:– Increasing catches without signs of decrease in CPUE
or average size. Model provides increasing recruitment but this conflicts with relatively stable age distribution.
• St. Croix—similar conflict albeit with increasing CPUE May be a data problem, particularly in recent years. May be an artifact from the way the SEFSC query was constructed.
Management Advice• Results are not yet suggestive that we understand the productive
capacity of this stock. Things may be complicated by a stock range that spans beyond the assessment area (BVI, PR, etc).
• May not apply to St. Croix (isolated sea mount not connected).• Results are suggestive that current fishing pressure is sustainable
—no evidence of decline in CPUE or average size on St. Thomas, however decline in average size observed on St. Croix.
• National Standard 1 advice on data-poor stocks with no evidence of decline: set catch limits as a function of average landings.
• Average landings have been increasing and current ACLs include low years at the start of the period, thereby reducing average.
• St. Croix may have data problem, and raises more concerns because the average size lobster is smaller and sizes have been decreasing.
Preliminary Conclusions
• Combination of catch weight, catch per unit effort, and size distribution of catches may be sufficient to assess the lobster stock.
• Recent data are necessary, as is further review of the catch, index, and size data.
• Even if assessment results are uncertain, management advice can be provided via a management strategy evaluation that compares policies against objectives (see Nowlis 2004, Bulletin of Marine Science)
2.4 Years