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Rerun of Gulf of Mexico red grouper assessment and projections

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Rerun of Gulf of Mexico red grouper assessment and projections Powered By Docstoc
					Rerun of Gulf of Mexico red grouper assessment and projections with
                 observer-derived discard estimates
                                            John Walter
                               NOAA National Marine Fisheries Service
                                 Southeast Fisheries Science Center
                                      75 Virginia Beach Drive
                                       Miami, Florida 33149

                                            January 16, 2011


Executive summary

This document provides an updated ASAP model run with revised estimates of historical discards in the
commercial handline and longline fishery based upon observer data from the years 2006-2008 and
updated projections taking into account the 18 inch commercial size limit change. Observer-based
handline discard estimates are approximately double the previous logbook based estimates used in the
2009 update and generally similar to the estimates used for longlines which used handline discard rates.
Commercial handline landings and discard mortality rate are relatively low. Hence these changes to the
discards had a relatively minor impact on the historical assessment, other than to slightly lower
estimates of current fishing mortality and slightly raise estimates of current SSB. The re-run model was
then projected with the 2009 landings (~4.6mp) and a best estimate of 2010 landings (~3.5mp), both of
which were substantially lower than the current TAC (7.57mp). Overall the main result of the
projections is that projected short term yields at Foy would be substantially higher than the 2011 TAC.
Short-term TAC for 2012 (7.218 mp) at OY (75% of Fmsy) is higher than the previous assessment
projections (5.528 mp). These differences are largely due to the substantially lower realized landings for
2009 and 2010 and, secondarily, due to the effect of the reduction in commercial size limit. The size limit
change results in fewer dead discarded fish in the commercial fishery, allowing the TAC to be met by
retaining more age 4 and 5 fish rather than discarding them dead.

Introduction

In between the 2009 red grouper update assessment and the development of management advice,
several years of observer data from the reef fish observer program have been collected and are
available for analyses. For the update assessment in 2009, commercial discard rates were obtained from
vessel logbook reporting. For longlines, the handline reporting rate was substituted due to perceived
under estimation of discards in the longline fishery. Preliminary analyses suggest that the observed
discard rates may be different than the status quo estimates and have motivated this analysis. Observed
length composition was used to obtain discard at age composition for the observed years (2006-2008)
and averages were used for years prior to observer data, for both the update and the current analyses.
Discard mortality rates were the same as used in the update assessment (45% for commercial longlines
and 10% for commercial handlines). Note that re-running the ASAP model covers the time period 1986-
2008 and the assessment model was not updated with CPUE, discards, length or age composition post-


                                                    1
2008. Time periods after 2008 represent projection time periods for which only estimates of 2009 and
2010 landings and a vector which accounts for changes in discarding due to the size limit were provided.

Methods

Estimates of discard rates from observers were available for the years 2006 (or 2007)-2009. Discard
estimates were only needed for the ASAP model period so discard data from 2009 was not used. Discard
rates were obtained by GLM modeling for both commercial longlines and handlines for the years 2006-
2008.

Due to inconsistencies in sample coverage of deep and shallow water fishing in the observer coverage
for 2006-2008, we used an average discard rate for the three years. This average discard rate was
multiplied by total longline or handline effort to obtain total discards. Each individual year; 2006,2007 or
2008, displayed substantial variability in discard rates, which, from visual inspection of the sampling
locations (not shown due to data confidentiality), appeared to have a different allocation of deep versus
shallow water sets. In the future, it may be possible to obtain separate bycatch rates for deep and
shallow sets. The more difficult part will be separating the total effort into deep versus shallow, but it is
possible for the years that logbooks have required reporting depth fished. However prior to this time
period, it may be difficult to adequately partition effort and some average allocation may have to be
used.

The new observer-based discard estimates and the older estimates used in the 2009 update assessment
are substantially different for the handlines (Table 1, Figure 1A) but fairly similar for longlines (Figure
1B).

Estimation of discards from observer data (new method)
• Began sampling vertical line (handline & bandit rig) in mid 2006
         – Reduced funding in 2008 = less sampling
• Sampling is random within gear/region/quarter strata
         – East and west Gulf of Mexico
         – Exception to non-random sampling of longline vessels in 2008
• On longline trips all catch is recorded, but may not be measured
• On vertical line trips, reels are randomly sampled with all hooks on the reel sampled, but not
necessarily measured
• Size composition of catch – including discards

Estimation of discards from logbooks (Previous method)
 handline trips
• Self reported discard logbook data (20% subsample of vessels)
• Used the same methods as in the previous assessment
• Stephens & MacCall method to identify trips within the fishery
• Defined four regions in eastern Gulf of Mexico
• Region specific discard rates determined for trips in the fishery and for all other trips
• Discard rates applied to total effort for each stratum (region * in or out of fishery) estimates derived
from the logbooks.

                                                      2
longline trips
• Appears to be underreporting of discards by longline vessels
• Followed 2006 method to estimate longline discards by applying handline discards:landings ratio
        to longline landings
• Used 2006 region specific discards:landings ratios

ASAP Model runs

The update assessment base advice model (red tide constant catchability’ model) was re-run with two
different vectors of total discard numbers, one for commercial handlines and one for commercial
longlines. No changes to the estimated age composition of the discards were made, though size
composition from the years 2007 and 2008 was used to obtain age composition in the original update
assessment in 2009.

Total observed discards were converted to dead discards with mortality rates of 45% for longlines and
10% for handlines. Dead discards were converted to discard numbers at age using the derived age
composition of the discards obtained by probabilistically aging the observed discard length composition
for the years 2006-2008.

Re-running the ASAP assessment model resulted in slight changes in the estimated parameters of the
stock recruitment function. These changes result in very slight changes to benchmark quantities.

2009 and 2010 landings

Commercial landings. The 2009 commercial landings are presented in Table 2 for red grouper. These
represent complete and final landings estimates for 2009. Landings data for 2010 are incomplete as of
the date of this analyses (December 2010). The most current set of data for 2010 landings comes from
real-time ITQ monitoring (https:ifq.sero.nmfs.noaa.gov/ifqgt/main.html#). Estimates of red grouper as
of December 14, 2010 were 2,704,023 gutted pounds out of a total quota of 5.75mp gutted pounds
(Table 2). To estimate the total landings for 2010, we calculated the average total fraction of landings for
2006-2009 for the months January-November (Table 2). This average fraction (0.91) was used as the
denominator to divide the ITQ monitoring landings to date. This could result in an underestimate of the
total landings if not all landings as of November 2010 were reported, but since two weeks of December
had already been completed by December 14th, this would mean that calling this landings through
November would slightly overestimate landings. Thus these two factors may offset each other, resulting
in total landings that are similar to the estimated number, 2,976,561.

Recreational landings. The best estimates of 2009 recreational landings are presented in Table 3. The
MRFSS estimates for 2010 were incomplete and only waves 1-4 data were available. To estimate the
remainder that would likely to be caught we estimated the ratio of the sum of waves 1-4 to the total for
years 2006-2009. We did not use 2005 data due to the closure of the fishery in the last waves. The
average ratio (0.81%) was used as the denominator to divide the 2010 totals to equal what is likely to be
caught in waves 5 and 6. While this is only an approximation, it appears clear that the total landings
from waves 1-4 in 2010 are only about 55% of the landings in 2009.

A cursory look at MRFSS effort data for 2010 showed a substantial decline in offshore (>10, >3 nm)
recreational trips, which likely has resulted in these reduced landings, as there does not appear to be a

                                                     3
substantial decrease in CPUE of red grouper, based upon anecdotal reports. Because of this decrease in
private recreational trips, we assumed that there was a similar decrease in headboat (HB) trips and in
Texas effort which would similarly reduce HB and TX landings. As neither HB nor TX landings were
available for 2010, we decremented the average landings for these sectors for the years 2006-2009 by
the observed reduction in MRFSS landings of red grouper between 2009 and 2010 (45% reduction).

For the 2009 and earlier landings data the Marine Recreational Fisheries Statistical Survey (MRFSS)
provides catch in numbers and weight. When not available, SEFSC has made weight substitutions to
provide a weight estimate. Weights from the MRFSS sample data were combined with calculated Texas
Park and Wildlife Department (TPWD) weights to obtain average weights across the region. The
headboat survey provides catch in numbers and weight. No weight substitutions were required for
headboats. TPWD provides catch in numbers only. Landings (number of fish) were converted to pounds
by converting lengths from the TPWD intercept data into weights using SEDAR endorsed length weight
equations. These weights were then combined with the MRFSS sample data to obtain average weights
across the region. These average weights were used to estimate catch in pounds in the TPWD survey.
This weight substitution method will be presented at SEDAR 22 (reference SEDAR-22-DW-16) and may
be modified in the future.

Projections

Projections were conducted with the Pro2Box projection software using the same specifications as for
the update assessments in 2009. The inputs changed slightly due to re-running the historical statistical
catch at age model. This resulted in a slight change in the stock recruitment relationship and some
changes to the numbers at age and fishing mortality rate at age matrices given to Pro2Box. The only
other changes were in the values used for the 2009 landings; previously assumed equal to the 2009 TAC,
but now replaced by estimates derived from landings data available as of September 2010 (see below)
and best estimates of commercial and recreational landings for2010.

Two projection scenarios were run for each species:

1. Estimates for 2009 and best preliminary estimate for 2010, 5.68 mp for 2011 and Fmsy for years
beyond 2011.

2. Estimates for 2009 and best preliminary estimate for 2010, 5.68 mp for 2011 and Foy = 75%*Fmsy for
years beyond 2011.

Evaluating impact of the reduction in size limit from 20 to 18 inches

Effective January 1, 2009 under an interim rule to Amendment 30B, the commercial size limit for red
grouper was reduced from 20 to 18 inches. This change in size limit was designed to improve yield per
recruit and reduce dead discards.

To evaluate the impact of the reduction in size limit on the predicted yields the probability of being
discarded at age was calculated based upon a normal distribution of size at age with a CV of length at
age equal to 0.16. The probability of being discarded at age (a) =P( size<SizeLimit|a). To evaluate the
change in the fraction discarded a change in probability of being discarded (delta_P(a) was calculated by
subtracting the P( size<SL_20|a)-P( size<SL_18|a). Then this change in the probability of being discarded


                                                     4
was multiplied by the number of discards for the commercial handline, longline fisheries. As the
probability of being discarded at age is reduced with the 18 inch size limit, this results in fewer discarded
fish which were then added to the retained fish to obtain a revised landed catch. The reduced
commercial discards were then added to the unchanged recreational discards to get a revised total
discards. The new total discards at age was then divided by the new total catch at age to get the
probability of being discarded dead at age. The end result was that the fraction discarded at age was
somewhat lower for ages 4 and 5 (Figure 2, Table 5).

This different probability of being discarded at age was applied to the Pro2Box projections which were
recoded to allow for a future change imposed in 2009, commensurate with the imposition of the 18 inch
size limit.

Re-estimating benchmarks

Re-running the ASAP model produces a slightly different stock-recruitment relationship and re-running
the projections with a different probability of discard at age results results in a different set of
benchmarks. Two different scenarios were projected, one with the previous benchmarks calculation,
unchanged for the 18 inch size limit and another set which account for the change. If the 18 inch
commercial size limit remains in place in the future, it could be expected to provide the management
benchmarks shown for this change.

Results and discussion

Estimated observer-based handline discards were much higher than previous logbook-based discards
(Table 1, Figure 1A), however observer-based longline discards were quite similar to the previous
estimates that used the handline reported rates (Figure 1B). As the longline has a 45% discard mortality
rate it is a more consequential source of mortality.

Commercial landings for 2009 and estimate landings for 2010 (Table 2) were substantially lower than
the commercial quota and lower than landings for 2006-2008. These are likely a result of restrictions
placed upon the bottom longline fishery in 2009 and 2010. Landings for 2009 are complete while
landings for 2010 are still preliminary but as these landings are current as of December 14, 2010, it is
likely that the final landings will be substantially lower than the quota in 2010.

Preliminary recreational landings for 2010 (Table 3) are also substantially lower than in years 2006-2009.
These lower landings appear to be a result of reductions in offshore fishing effort as noted above. Even
though waves 5 and 6 are not complete, it seems unlikely that landings for 2010 will come close to the
recreational quota. Note that the new landings for 2009 and 2010 were only used in the projections and
have no influence on the ASAP model that runs through 2008.

Changing the size limit from 20 to 18 inches results in an approximately 12% higher probability of being
retained for age 4 and 9% higher for age 5. These higher probabilities translate into reduced discards
and higher numbers of retained fish in ages 4 and 5. This effectively reduces the harvest of older fish and
would lead to a different long-term pattern of f fishing mortality and different benchmark values.

When the new discard numbers were used in the ASAP model, they led to some slight differences in the
estimated numbers of recruits, spawning stock biomass and total F and discard F (Figure 3). This


                                                     5
resulted in a slightly higher estimate of spawning stock biomass in 2008, higher fishing mortality rates
historically and a lower current fishing mortality rate. This somewhat counter-intuitive result that higher
historic discards lead to an improved estimate of current stock status in 2008 is a function of the
influence of higher historic discard fishing mortality rates and a relative reduction in discard F in recent
years (Figures 3 and 4). This relative reduction in discard F can be seen in the recent declines in the
model-predicted discards for the observer-based discards versus the logbook discards (Figure 5).

In addition, another effect of the increased level of historic discards is a slightly more productive stock
recruitment relationship. Re-running the ASAP model with the new discard probability at age (Table 5)
also leads to re-estimation of the Beverton-Holt spawning stock recruitment relationship. In this case,
the 2010 re-run stock recruitment function has a slightly higher level of asymptotic recruitment than the
2009 red tide model (Figure 6).

Two scenarios for benchmark calculations are shown in Table 6. The first column is the results from the
red tide model from the 2009 update. The second column is the re-run model with benchmarks re-
calculated only due to the change in the stock-recruitment relationship and the change in historic
discards. The third column (ReRun 2010, with diff benchmarks) estimates new benchmarks accounting
for the change in size limit. Providing all columns isolates the sources of the differences in benchmark
quantities. Re-running the ASAP model with the new discards and new stock recruitment function has
only a negligible change in the estimated quantities. In contrast, the 18 inch commercial size limit results
in higher Fmsy and lower SSBmsy than red tide model or the model that did not take the size limit change
into account in the benchmarks.

These new benchmarks and discards result in a slightly improved estimate of stock status in the final
year of the ASAP model (2008) than in the 2009 update (Figure 7). When projected, this improved initial
status coupled with the much lower landings estimated for 2009 and 2010, gives higher yields at Fmsy
and Foy then estimated for the 2009 update (Table 6). Projected yield at Fmsy for 2010 (9.434mp) is
higher than the MSY as SSB is projected to have built higher than SSBmsy. Yield at Foy for 7.218 mp is not
as high as the equilibrium yield at Foy but is increasing in the near future as SSB approaches SSB at Foy.

Overall the main result of the projections is that projected short term yields at Foy would be higher than
the 2011 TAC. This is due to four factors. First the stock status is estimated to be slightly higher in 2008
than in the previous update due to the higher historical discard estimates relative to current discards.
Second the re-estimated stock-recruit relationship is slightly more productive. Third the imposition of
the reduced size limit provides the benefit of fewer dead discarded fish in the commercial fishery, thus
the TAC is obtained by retaining age 4 and 5 fish rather than discarding them dead. This reduces the
relative fishing mortality on older fish. Fourth, and most importantly, catches substantially lower than
the TAC for 2009 and 2010 are predicted to have allowed the population to increase, resulting in higher
TACs at Foy in the near future.




                                                      6
Table 1. New observer based discards and old logbook-based total discards in number.

         New observer based     Old logbook based
           vertical              vertical
  year     line        longline line         longline
  1990       418,042 495,369 233,263 432,644
  1991       654,144 897,151 347,371 811,121
  1992       525,575 554,577 436,300 403,550
  1993       480,906 466,788 197,971 540,683
  1994       616,427 580,159 238,279 412,423
  1995       566,427 489,431 218,443 514,351
  1996       552,383 533,637 277,560 638,383
  1997       513,618 616,833 267,806 715,060
  1998       495,392 563,964 260,986 597,663
  1999       537,860 640,128 335,615 676,715
  2000       528,366 642,608 314,057 567,579
  2001       452,107 642,252 314,818 628,331
  2002       504,075 562,450 309,319 588,338
  2003       519,057 615,285 309,429 605,732
  2004       489,793 593,674 266,639 631,573
  2005       579,042 449,346 232,954 576,157
  2006       613,368 540,488 237,974 541,735
  2007       670,047 490,783 240,722 338,735
  2008       612,053 503,986 235,615 505,406




                                                  7
Table 2. Red grouper commercial ladings and estimated landings for 2010. The average percentage of
landings obtained in months 1-11 was used as the denominator to divide the ITQ monitoring landings as
of December 14, 2010 to estimate total landings in 2010.

     Month           2006      2007       2008         2009
       1            487311    191736     209159       326437
       2            212625    159537     235532       180974
       3            227074    130385     154759       139534
       4            463354    176337     523653       334244
       5            568868    176138     529415       414557
       6            573938    403527     693112       366251
       7            503541    458808     490903       360984
       8            659560    452271     346447       392133
       9            436812    406674     382374       344231
      10            347968    338942     385157       265114
      11            287478    341820     326979       294553
      12            393998    472686     461805       237828

 TOTAL              5162527 3708863 4739295 3656839

 sum 1_11           4768528 3236176 4277490 3419011
 percent of total     0.92    0.87    0.90    0.93

 ITQ total as of Dec 15, 2010                         2704023
 average percent of landings in months
 1-11                                                  0.91
 estimated commercial landings in
 2010                                                 2976561




                                                  8
Table 3. Recreational landings obtained from the Annual Catch limit database. 2010 landings were
estimated by using the average fraction of waves 1-4 to the total as the denominator to divide the 2010
wave 1-4 totals. For headboat landings in 2010, the average landings from 2006-2009 were divided by
the fraction

        wave          2006      2007   2008   2009   2010
         1           116254    47769 148583 20391 13866              jwalter:
         2           114978    130560 91723 50806 35937              take fraction of
         3           412099    173147 189465 293813 204271           MRFSS2010/
                                                                     MRFSS2009 for
         4           148031    325224 283836 393021 139777           waves 1-4 ~ 50%
         5           117069    115888 64925 41745
         6           26980     199393 76788 83917

HB                    25479 24674 37604 29583 15370                    jwalter:
                                                                       average of 06-09
TX                           152     73            59
MRFSS                935410 991981 855321 883694 489211

sum waves 1-4       791362 676700 713608 758032 393850 jwalter:
                                                       take sum of waves 1-
avg % for waves 1-4 0.85    0.68   0.83   0.86         4 divided by the avg
avg waves 1-4                                    0.81  fraction that waves 1-
                                                                     4 represent
SUM_REC              960890 1016807 892998 913277 504640




                                                   9
Table 4. Total red grouper landings (1986-2010). The 2010 landings are derived from preliminary
landings data (shaded values).

YEAR    bandit     handline    longline    other    spear      trap      trawl   Headboat    MRFSS      Grand Total
1986               3,177,814   2,488,241            9,459    750,020     5,828   112,910    1,939,923   8,484,195
1987               2,602,748   3,748,156    38      17,970   482,485     239      84,369    918,192     7,854,196
1988               2,108,492   2,190,365    39      3,978    571,370     1,287    99,121    2,209,057   7,183,708
1989               3,804,399   3,203,200    60      10,426   611,340     1,441   128,851    2,192,067   9,951,784
1990               2,484,177   2,017,380            7,137    360,659     925      87,319    1,130,548   6,088,145
1991               2,138,259   2,591,424   1,524    37,747   395,351     2,288    57,955    1,707,006   6,931,554
1992               1,491,184   2,410,857    830     15,133   601,907     577      50,240    2,704,152   7,274,881
1993               1,346,061   4,314,563   36,434   16,905   717,948              72,633    2,117,663   8,622,208
1994               1,280,237   2,714,441   29,231   22,303   917,135              52,815    1,869,132   6,885,296
1995               1,243,899   2,481,819   8,217    16,208   1,057,820            89,895    1,775,679   6,673,537
1996               936,238     2,994,100   1,937    14,375   559,153              80,504    753,011     5,339,316
1997               1,058,228   3,137,381   1,476    15,524   707,279              23,957    556,406     5,500,251
1998               840,444     2,856,022   7,536    13,859   317,678              22,269    671,352     4,729,161
1999               1,298,480   3,937,218   15,258   17,730   770,826              45,810    1,161,158   7,246,482
2000               1,807,817   2,996,184   25,854   15,110   1,042,067            48,717    2,122,910   8,058,659
2001               1,639,910   3,524,640   24,237   18,275   770,749              30,181    1,350,483   7,358,475
2002    826,126    862,068     3,227,396   9,180    22,421   1,003,746            23,508    1,664,294   7,638,738
2003    721,665    447,045     3,066,357   4,156    16,119   715,759              38,489    1,296,770   6,306,361
2004    954,679    489,439     3,528,979   8,772    17,749   777,370              65,145    3,087,562   8,929,695
2005   1,027,654   430,394     3,324,830   2,302    18,844   633,537              75,009    1,365,801   6,878,371
2006    937,999    455,401     3,141,704    782     12,363   614,278              25,479    935,410     6,123,416
2007   1,031,216   553,530     2,077,544   2,090    18,897    25,585              24,674    991,981     4,725,518
2008   1,339,704   520,143     2,850,100   1,054    28,293                        37,604    855,321     5,632,219
2009   1,728,154   739,599     1,132,994   26,551   29,541                        45,582    932,741     4,635,162
2010                                                                                                    3,481,201




                                                        10
Table 5. Old(20 inch comm. size limit) and new (18 inch commercial size limit) probability of being
discarded at age. The reduction in size limit reduces the probability of being discarded.

                          new prob
            old prob of    discard
              discard     (18 inch
 age                         SL)     Difference
        1    0.995        0.995        0.000
        2    1.000        1.000        0.000
        3    0.987        0.976        0.011
        4    0.866        0.744        0.123
        5    0.448        0.356        0.093
        6    0.206        0.173        0.033
        7    0.094        0.084        0.010
        8    0.047        0.044        0.003
        9    0.038        0.036        0.002
       10    0.040        0.039        0.001
       11    0.031        0.030        0.001
       12    0.028        0.028        0.001
       13    0.026        0.026        0.000
       14    0.024        0.024        0.000
       15    0.023        0.022        0.000
       16    0.021        0.021        0.000
       17    0.019        0.019        0.000
       18    0.018        0.018        0.000
       19    0.017        0.017        0.000
       20    0.015        0.015        0.000




                                                   11
Table 6. Required SFA and MSRA evaluations for Gulf of Mexico red grouper. The central model was not
projected for the 2010 re-run with observer discards and the 18 inch commercial size limit. Yields are
mil. pounds, gutted weight, spawning stock measures (SSB, MSST) are in million grams of mature female
gonad weight. Yields come from the deterministic run of the projection model. Gray values are the
actual estimated landings for 2009 and 2010 used in the current projections. Blue values are 2011 TAC.

                                                          Red       ReRun       ReRun 2010, with diff
     Criteria                    Definition
                                                          Tide       2010          benchmarks
                       Mortality Rate Criteria
    FMSY or proxy                  Fmsy                  0.1865     0.1853             0.1922
      MFMT                         Fmsy                  0.1865     0.1853             0.1922
        FOY                   75% OF FMSY                0.1399     0.1389             0.1441
     FCURRENT            Geom mean 2005-2007             0.1610     0.1563             0.1563
 FCURRENT/MFMT           Geom mean 2005-2007             0.8633     0.8439             0.8135
     Base M                                               0.140      0.140              0.140
                          Biomass Criteria
      SSBmsy            Equilibrium SSB @ Fmsy           712.700    713.49             696.255
      MSST                (1-M)*SSBMsy M=0.14            612.922    613.601            598.779
    SSBCURRENT                    SSB2008                615.524    650.50             650.50
 SSCURRENT/MSST                   SSB2008                 1.004      1.060              1.086
 Equilibrium MSY         Equilibrium Yield @ FMSY         7.670      7.818              8.10
 Equilibrium OY          Equilibrium Yield @ FOY          7.498      7.875              7.927
        OFL              Annual Yield @ FMFMT
                                   2009                   7.498      4.635              4.635
                                   2010                   6.425      3.481              3.481
                                   2011                   6.626      5.680              5.680
                                   2012                   6.737      9.132              9.434
                                   2013                   6.940      9.040              9.289
                                   2014                   7.053      8.859              9.060
                                   2015                              8.704              8.864
                                   2016                              8.592              8.720
 Annual OY (ACT)           Annual Yield @ FOY
                                 2009                     7.570      4.635              4.635
                                   2010                   4.913      3.481              3.481
                                   2011                   5.260      5.680              5.68
                                   2012                   5.528      6.982              7.218
                                   2013                   5.859      7.176              7.389
                                   2014                   6.099      7.274              7.463
                                   2015                              7.358              7.525
                                   2016                              7.442              7.59
                    Annual Yield (2012) @ 65% FMFMT                  6.098              6.306
                    Annual Yield (2012) @ 75% FMFMT                  6.982              7.218
                    Annual Yield (2012) @ 85% FMFMT                  7.852              8.115


                                                    12
Figure 1. New observer based handline (A) and longline (B) discards and old (status quo) logbook-based
total discards in number.

A.




B.




                                                  13
Figure 2. Change in probability of discard dead at age due to the commercial size limit change from 20
inches to 18.




                                                   14
Figure 3. SSB, recruits, total F and discard F for the 2009 update assessment and the 2010 re-run with
observer-based discards.

  SSB                       2009 update
                                                                          Recruits    2009 update
                            new disc
              900.0                                                                   new disc
                                                                          30.0
  Millions




                                                               Millions
              800.0
                                                                          25.0
              700.0

              600.0                                                       20.0

              500.0




                                                               recruits
  SSB




                                                                          15.0
              400.0

              300.0                                                       10.0

              200.0
                                                                           5.0
              100.0

                   0.0                                                     0.0
                     1985    1990         1995   2000   2005



     Total F                    2009 update                               Discard F     2009 update
                                new disc                                                new disc
       0.35
                                                                           0.08

             0.3                                                           0.07

       0.25                                                                0.06

             0.2                                                           0.05
 F




                                                                           0.04
                                                                 F




       0.15
                                                                           0.03
             0.1
                                                                           0.02
       0.05
                                                                           0.01
              0
                                                                             0




                                                               15
Figure 4. Discard F for commercial longline and handline.


               Discard F, longline                                                                       update 2009                              Discard F, handline                                                                     update 2009




                                                                                                                                 F
                                                                                                                                                                                                                                          new discards
F




                                                                                                         new discards
                                                                                                                                 0.014
 0.06
                                                                                                                                 0.012
 0.05
                                                                                                                                  0.01
 0.04
                                                                                                                                 0.008
 0.03
                                                                                                                                 0.006
 0.02                                                                                                                            0.004
 0.01                                                                                                                            0.002

              0                                                                                                                                   0
                   1985                       1990                  1995                   2000                     2005                                1985                    1990                  1995                 2000                 2005




Figure 5. ASAP model predicted longline and handline discards. New predictions use the observer-
estimated discards. Old prediction use the previous logbook discards.

 LL predicted discards                                                                                                             HL predicted discards
                                1800                                                                                                                              300
                                                                                                                                                      Thousands
                    Thousands




                                1600
                                                                                                                                                                  250
                                1400
  discard (gutted lbs)




                                1200                                                                                                                              200
                                                                                                                                  discard (gutted lbs)




                                1000
                                                                                                                                                                  150
                                800                                                                                        new                                                                                                                              new
                                600                                                                                        old                                    100                                                                                       old
                                400
                                                                                                                                                                   50
                                200
                                  0                                                                                                                                0
                                                                                                                                                                        1986
                                                                                                                                                                               1988
                                                                                                                                                                                      1990
                                                                                                                                                                                             1992
                                                                                                                                                                                                    1994
                                                                                                                                                                                                           1996
                                                                                                                                                                                                                  1998
                                                                                                                                                                                                                         2000
                                                                                                                                                                                                                                2002
                                                                                                                                                                                                                                       2004
                                                                                                                                                                                                                                              2006
                                                                                                                                                                                                                                                     2008
                                       1986
                                              1988
                                                     1990
                                                            1992
                                                                   1994
                                                                          1996
                                                                                 1998
                                                                                        2000
                                                                                               2002
                                                                                                      2004
                                                                                                             2006
                                                                                                                    2008




                                                                                                                                 16
Figure 6. Estimated stock recruitment relationship for the three previous ASAP red grouper models
(2007, 2009 central and 2009 red tide model) and the most recent model with new discard estimates.




                                                 17
Figure 7. Comparisons of F/Fmsy and SSB/SSBmsy for the 2009 update and the 2010 observer-based
discard estimates.




Figure 8. Short term yield projections for three scenarios. The first is the base 2010 run (blue), second is
the re-run with observer discard data and old benchmarks and the third the re-run with different
benchmarks calculations. The 2009 and 2010 quotas are shown in black. Not the substantial undercatch
of the quotas in 2009 and 2010.




                                                     18

				
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