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PROSPECTS FOR THE SUSTAINABLE MANAGEMENT OF PUBLIC OYSTER RESOURCES.

INTRODUCTION

Common-pool resources are especially vulnerable to over-exploitation and habitat loss. Allocation of access and limitation to extractive practices are often ineffective, and common-pool resources typically degrade to a state described as "The Tragedy of the Commons." The tragedy of the commons results from a competitive calculus, in which the benefit to the individual exploiter of a public resource exceeds his portion of the common exploitive cost plus the individual costs, if any, of noncompliance (Hardin 1968).

Beck et al. (2011) estimate that 85% of oyster reefs worldwide have been lost. In many bays and estuaries, more than 90% of reefs are functionally extinct. Most of the remaining wild capture (75%) comes from North America, in particular from the Gulf of Mexico. Historical accounts include Ford (1997) and MacKenzie (1996, 2007). Kirby (2004) described the sequence of reef destruction and fisheries collapse in North America. Fishery collapse began in estuaries nearest large northern urban centers and spread southward along the U.S. Atlantic coast. As resource depletion occurred, additional oysters were imported from areas fished from evermore distant southern estuaries. The historical sequence of exploitation and the increasing landings in Texas and Louisiana relative to North America suggest that oyster reefs there are in greatest danger of degradation (Kirby 2004). Zu Ermgassen et al. (2012) provide a further update of oyster population condition. Powell (2017) reviews recent trends in the Gulf of Mexico.

The oyster populations and reefs of the Public Oyster Grounds (POG) of Louisiana (Fig. 1) are common-pool resources that have been in decline (Fig. 2) since 2001 (Soniat et al. 2012, LDWF 2016). The Louisiana oyster grounds consist of nearly 1.7 million acres of POG and approximately 404,000 acres of private leases. The POG are used as a source of seed oysters (shell length, L, less than 75 mm) that are transported to private leases for grow out and subsequent marketing. Market-size (P greater than or equal to 75 mm) or "sack" oysters are also allowed to be directly marketed from the POG (Banks et al. 2016, LDWF 2016).

The long-term average (1961-2015) landings of eastern oysters (Crassostrea virginica) produced from the POG and private leases is about 11 million pounds of meat (Fig. 2). In years of abundance of oysters on the POG (2000-2002), public grounds supplied about 50% of the combined annual yield; in years of scarcity (2012-2014), they supplied about 10% of the same (LDWF 2016). Thus, although private and public production show considerable variation, the interplay of private and public activity results in relatively stable long-term production. The success of the Louisiana oyster industry is due in part to this public/private partnership, in which the Louisiana Department of Wildlife and Fisheries (LDWF) plants cultch and manages the public grounds for seed production and transplant to private leases. Dugas (1988), Keithly and Roberts (1988), and Wirth and Minton (2004) provide historical accounts. The decline in stock abundance on the POG, however, directly threatens the sustainability of the public resource and indirectly threatens the sustainability of the private resource, which is subsidized by seed and cultch from the public grounds.

The present study investigates the sustainability of the public resource only. A sustainability criterion and a modeling scenario for sustainable fishing of sack and seed oysters from the Louisiana POG, which is broadly applicable to subtidal eastern oysters in North America, is defined and proposed. The 2018/2019 oyster season has been used as an exemplar representing the present state of the resource and the implications of management measures that would achieve sustainability.

MATERIALS AND METHODS

Study Area

Coastal fisheries in Louisiana, including the oyster fishery, are managed by the LDWF. The coast is subdivided into management units termed Coastal Study Areas (CSAs), which are watersheds or contiguous watersheds (Fig. 1). Seven CSAs are designated, from CSA 1 in the east to CSA 7 in the west. In 2012, LDWF consolidated CSA 1 with CSA 2 and CSA 4 with CSA 5; the traditional designation is used herein. Louisiana POG are located in all CSAs (Fig. 1). They include the public grounds of Mississippi Sound (MS), Lake Borgne (LB), and the Biloxi Marsh (BM) in CSA 1; Breton Sound (BS) in CSA 2; Hackberry Bay (HB) and Barataria Bay (BB) in CSA 2; Terrebonne Bay (TB) in CSA 4; the Sister Lake (SI) area in CSA 5; Vermilion Bay (VB) in CSA 6; and Lake Calcasieu (LC) and the Louisiana portion of Sabine Lake (SL) in CSA 7. Location, CSA, and reef size are given in Table 7.

Oyster habitat in Louisiana is characterized by copious freshwater input, high turbidity, microtidal conditions, and shallow (1-4 m) water depth (Melancon et al. 1998). Intertidal oysters are found at the seaward edge of their local distribution, but are not commercially significant, are not sampled by the LDWF, and are not a part of the present study.

Stock Assessment

The LDWF conducts annual quantitative fisheries-independent surveys on all POG. Divers remove oysters and surficial cultch from five grid samples (1.0 m2 or 0.25 m2) at each reef (Table 7). Live oysters and boxes (dead oysters with articulated shells) are counted, measured, and assigned to 5-mm size bins. (In the present study, oyster "length" is used in a fisheries context and is equivalent to standard height.) Oyster abundance on a reef is determined by multiplying mean oyster density by the reef acreage (Table 7). Details of sampling methodology, and interannual differences in assessed reef size and stock size are available as annual stock assessment reports (e.g., LDWF 2016).

Model Overview

Primary processes and linkages of the sustainable oyster fishing model are shown in Figure 3. Oyster size and number, and cultch type and density are primary inputs to the model. For each size group, mortality is simulated and new shell is added to the reef as the size-dependent carbonate contribution of dead oysters. Both mortality and growth are simulated as functions of oyster size, and environmental temperature (or season) and salinity. Fishing effort and season duration for seed and sack oysters are used to compute the number of sacks of oysters fished. For each cultch type (oyster shell, limestone, clamshell, hooked mussels, and concrete), the volume of cultch fished is determined, natural loss is calculated, and shell added via oyster mortality is credited to the reef cultch. The time step for the oyster and cultch calculations is one month. When calculations for all size classes of oysters, all cutch types, and all months are exhausted, the results are collected and a determination of sustainable harvest is made.

Details of model equations and processes are provided by Soniat et al. (2012). Model equations and parameters are provided in Table 1, whereas model constants and coefficients are shown in Table 2. Notable changes from previous model implementations (Soniat et al. 2012, 2014) include the addition of modified equations for size-specific growth and mortality as a function of water temperature and salinity (Lowe et al. 2017, 2018). Growth (Csp) of spat (f < 25 mm) is

[G.sub.sp] (l, t) = -0.055 X [T.sup.2.sub.t] -0.12 X [S.sup.2.sub.t] + 2.91 X [T.sub.t] -26.18. (1)

Growth ([G.sub.se]) of seed oysters (l [less than or equal to] 25 mm and <75 mm) is

[G.sub.se] (l, t) = -0.036 x [T.sup.2.sub.t] + 1.97 x [T.sub.t] + 0.012 x [S.sub.t]-19.49. (2)

Growth ([G.sub.sa]) of sack oysters (l [greater than or equal to] 75 mm) is

[Q.sub.sa] (l,t) = -0.0074 X [T.sup.2.sub.t] -0.0068 X [S.sup.2.sub.t] + 0.29 X [T.sub.t] + 0.22 X [S.sub.t] -2.18. (3)

Lowe et al. (2017, 2018) were able to derive a mortality equation for sack oysters only. The monthly mortality fraction (M) for sack oysters is

[M.sub.sa] (l, t) = 0.00095 X [T.sup.2.sub.t] +0.0027 x [S.sup.2.sub.t] -0.037 x [T.sub.t] -0.072 x [S.sub.t] +0.78, (4)

where l is the oyster length (mm), t is the time, [T.sub.t], is the temperature ([degrees]C) at time t, and [S.sub.t] is the salinity at time t. Mortality rates for spat and seed are parameterized as previously (Soniat et al. 2012, 2014) and are given in Table 1.

Spat growth (Eq. 1) is maximal at high T(>27.0[degrees]C) and high S (>22). Spat growth declines above 30[degrees]C and is markedly reduced at Tless than 20[degrees]C and S less than 15. Seed oyster growth (Eq. 2) is increased at T between 22[degrees]C and 30[degrees]C. Seed growth is maximal at a T of 27.8[degrees]C and an S of 26.8, and declines at T greater than 30[degrees]C and at combinations of low T (<15[degrees]C) and low S (<15). Growth of sack-sized oysters (Eq. 3) is maximized at lower T and S than that for spat and seed. Growth is reduced at the extremes of both T and S; the most significant reduction occurs at T greater than 30[degrees]C and S less than 10. Mortality of sack oysters (Eq. 4) is minimal at a T of 17.1[degrees]C and an S of 12.4 (Lowe et al. 2017, 2018).

Temporal and Spatial Restrictions to Sack and Seed Fishing

In CSA 1, fishing was restricted to a November through February season with sack fishing evenly distributed across the season and seed fishing restricted to November. In CSA 2, sack-only fishing was allowed during a November through February season; effort there was evenly distributed. Coastal Study Area 3 was open to fishing for sack oysters from November through February with effort evenly distributed; sack fishing was allowed in November only. Fishing was not permitted in CSA 4 because of a lack of resource. Closure of CSA 5 is the result of a policy of biennial rotation, paired with contrapuntal openings in HB (CSA 3). The season in CSA 6 extended from November through March, with most of the sack effort and all of the seed effort exerted in March. Coastal Study Area 7 includes LC and SL (Fig. 1); where fishing is allowed, only sack fishing is permitted. Sack fishing in LC was allowed from November through February, with effort evenly distributed in those months. Sabine Lake is never open to fishing and is thus not included in the present simulations (Tables 3 and 4).

Simulation Scenarios

The simulations of sustainable harvest require as input a prescribed fishing season, fishing location, sack and seed fishing pressures (Table 3), and the proportion of sack to seed fishing (Table 4). Monthly mean T from central coastal Louisiana is used to construct a look-up table (Table 5) that is applied to all reefs. Mean monthly T varies from 11[degrees]C in January to 29[degrees]C in July and August. Three monthly S profiles (Melancon et al. 1998) are used in simulations for all reefs, providing low (annual mean S = 8.8), moderate (annual mean S = 14.4), and high (annual mean S = 20.7) salinity scenarios (Table 6).

A no-net-cultch-loss (NNCL) reference point is used as the endpoint for simulations. That is, when cultch density in the simulation equals the original (stock assessment) density, the simulation ceases. Initial simulations are conducted without fishing. If without fishing the reef loses cultch, it is considered "not fishable" (Table 7), and no further simulations are conducted. Such reefs have an insufficient density of oysters needed to support reef stasis, much less carbonate removal by fishing. "Fishable reefs" are further simulated to determine sustainable harvest, using the NNCL reference point. In some cases, the model achieves NNCL and the simulation is solved; in other cases, the simulation exhausts a priori constraints (fishing season, sack and seed pressures, and proportion of sack to seed fishing) before reaching NNCL (Table 7). Such reefs have a net cultch gain. Both conditions are considered sustainable. Sustainable harvests of sack and seed are determined by reef for the three S scenarios (Table 7); sustainable harvests from reefs within a CSA are summed to give CSA totals, and CSA totals are summed for statewide totals (Table 8).

RESULTS

Sustainable harvests by reef are shown in Table 7. Of 84 reefs, 62 showed no possible sustainable harvest of seed or sack oysters under any S scenario (high, moderate, and low). Four reefs showed a sustainable harvest under some S scenarios (Hackberry 2008 Cultch Plant, low S, moderate S; Hackberry 2012 Cultch Plant, moderate S; Highspot Reef, low S; and Middle Reef, low S, moderate 5). Eighteen reefs, just 21.4% of the total, showed sustainable harvest of seed or sack oysters under all S scenarios.

In CSA 1, a sustainable harvest of seed oysters (abbreviated hereafter as [H.sub.SE]) and sack oysters (abbreviated hereafter as [H.sub.SA]) was available (Table 7). For the low S regime, [H.sub.SE] and [H.sub.SA] were 7,324 and 28,757 sacks, respectively. For the moderate S regime, [H.sub.SE] was 6,681 sacks and [H.sub.SA] was 36,217 sacks. Under high S conditions, [H.sub.SE] was 5,968 sacks, whereas [H.sub.SA] was 9,018 sacks. In CSA 2, a sustainable harvest of sack or seed was not possible on any reef. Coastal Study Area 3 supported a small sustainable harvest-an [H.sub.SE] of 473 sacks and an [H.sub.SA] of 1,039 sacks at low S, an [H.sub.SE] of 374 sacks and an [H.sub.SA] of 1,057 sacks at moderate S, and an [H.sub.SE] of 409 sacks and an [H.sub.SA] of 242 sacks at high S. No fishing was scheduled in 2018/2019 in CSAs 4 and 5 (see Methods and Table 4), and so no simulations were run. In CSA 6, applying the low S scenario, [H.sub.SE] was 3,680 sacks and [H.sub.SA] was 43 sacks. Applying the moderate S scenario, [H.sub.SE] was 1,526 sacks and [H.sub.SA] was 3 sacks. No sustainable harvest was available under the high S scenario. No seed fishing is allowed in CSA 7 (see Methods and Table 4), and so simulations were carried out for sack fishing only. The low S regime estimate yielded an [H.sub.SA] of 91,147 sacks, the moderate S regime estimate an [H.sub.SA] of 133,339 sacks, and the high S regime estimate an [H.sub.SA] of 41,095 sacks. Thus, for 2018/2019, CSA 1 provides the greatest sustainable harvest of seed oysters, whereas the greatest sustainable harvest of sack oysters is available in CSA 7.

Total sustainable harvests projected for 2018/2019 under the NNCL definition of sustainability are presented as the sum of harvests from all CSAs for each S regime (Table 8). For low S, the [H.sub.SE] was 11,477 sacks and [H.sub.SA] was 120,986 sacks. For moderate S, [H.sub.SE] was 8,581 sacks and [H.sub.SA] was 170,616 sacks. For high S, [H.sub.SE] was 6,377 sacks and [H.sub.SA] was 50,355 sacks. Thus, the maximum [H.sub.SE] was achieved at low S, whereas the maximum [H.sub.SA] was achieved at moderate S. Seed harvests varied among S regimes by a factor of about 1.8, whereas comparable sack harvests varied by a factor of about 3.4. Regardless, the total projected sustainable landings are well below the historical mean (Fig. 2).

DISCUSSION

Harvests were projected for the 2018/2019 season under the NNCL definition of sustainability. Statewide, 62 of 84 reefs considered herein showed no sustainable harvest under any S regime. Stock sizes of seed and sack oysters in 2018 are at historic lows--well below long-term averages--and continue a declining trend apparent since 2000 (Fig. 2). Soniat et al. (2012) applied shell-budget modeling for a retrospective analysis of the POG of CSA 2. They determined the extent to which actual harvest exceeded sustainable (simulated) harvest. From 1999 to 2009, sustainable harvests of sack and/or seed oysters were exceeded in 2002 to 2005 and 2007 to 2008. The greatest estimated sustainable harvest in CSA 2 was 816,468 sacks of seed oysters (in 2000) and 3065,531 sacks of sack oysters (in 2001). This contrasts with an estimated maximum sustainable harvest of 11,477 sacks of seed and 170,616 sacks of sack oysters for the entire state of Louisiana in 2018 (Table 8). The lack of fishable reefs, low stock abundances, and diminishing harvests (sustainable or otherwise) indicate a decline in the common-pool resource of the state POG.

The cause or causes of the "Tragedy of the Commons" of POG are the subject of considerable debate and speculation among oyster growers, agency biologists, academicians, and members of nongovernment organizations (see Mann & Powell 2007). Ultimately, reefs are sustained by recruitment, without which they inevitably decline. Without recruitment, no other trajectory other than reef degradation is possible--both in situ and, in the present formulation, in silico. Sustainable reefs produce and recruit larvae, provide refuge for newly settled spat, and support survival and growth to adult size. Natural (non-fishing) mortality of large adult oysters provides the bulk of the carbonate essential to maintain shell balance or reef accretion (Powell & Klink 2007, Mann et al. 2009, Southworth et al. 2010). Thus, a sufficient number of oysters must grow to adult size and their shells remain in place to support reef persistence. Recruits in the present model are young-of-the-year oysters, as determined by the annual stock assessment. The sustainable oyster fishing model determines sustainable harvest, given the initial stock abundance and size distribution. Implicit in the application of the model is the notion that quality reefs support reproduction, larval set, and spat survival. Soniat (2017) explored the relationship between cultch density and oyster density and found that essentially all of the harvest from Louisiana POG in the 2016/2017 oyster season was from reefs with [greater than or equal to] 1,000 g/[m.sup.2] of cultch and [greater than or equal to]25 oysters/[m.sup.2]. This cultch value is considerably below an analogous division by Mann et al. (2009) for the James River and by Southworth et al. (2010) for the Great Wicomico, both Chesapeake Bay, which suggests that either a division at 1,000 g/[m.sup.2] does not identify the most productive reefs or that recruitment potential per gram carbonate is higher for the Louisiana reefs in comparison with those in the Chesapeake Bay. The latter is more likely (Powell et al. 2012). The establishment of reef cultch and oyster abundance reference points is the subject of continued study (Powell et al. 2018). Nonetheless, the present model permits shell gain by constraining fishing by area, type (sack versus seed), effort, and season (Tables 3, 4 and 7).

The history of management of federal fisheries might focus on the period before and after adoption of statutory reference points related to maximum sustainable yield (Restrepo et al. 1998). Many federally managed stocks have been rebuilt over the last 20 y (Rosenberg et al. 2006, NOAA 2017). By contrast, although much attention has been given to management of the East and Gulf coast oyster fisheries (Jordan & Coakley 2004, Mann & Powell 2007, Vanderkooy 2011), with the exception of the New Jersey fishery in Delaware Bay (Powell et al. 2018), none has performed sustainably or been rebuilt to sustainability over this time frame. The lamentable status of the Louisiana public grounds unfortunately is not unusual (Hargis & Haven, 1994, Rothschild et al. 1994, Zu Ermgassen et al. 2012, Camp et al. 2015, Pine et al. 2015). Although proximate reasons may be manifold, they certainly include three. (1) Climate change likely has reduced the productivity of the oyster in the Gulf of Mexico (Powell 2017), a reduction that imperils time-honored approaches to management that have not proved sufficiently responsive to challenge. (2) Overfishing has occurred chronically, abetted by the absence of a modern reference point system to judge the status of the stock (Powell et al. 2018), an issue to which the model used in this contribution was designed to address. (3) The seed fishery is extremely destructive in that it removes both live animals and cultch, the latter in disproportionate measure without, in most cases, sufficient production of carbonate for repayment (Soniat et al. 2012).

For the Ancients, comedy was not funny--or at least it need not be. Instead, comedy was a chronicle of events for which a happy ending is possible. By contrast, tragedy was a narrative for which a disastrous conclusion is inevitable. Hardin (1968) gives conditions under which tragic outcomes are averted ("mutual coercion mutually agreed upon"); thus, the term tragedy is used therein in the modern sense to indicate a disastrous, yet avoidable consequence. For the oyster industry, sustainable harvest quotas and cultch removal rates derived from shell-budget-based modeling and applied through effective management make happy endings possible. Thus, whereas the chronicle of the use of public oyster resources is tragedy in the modern sense, oyster resource management is comedy in its ancient meaning.

ACKNOWLEDGMENTS

Funding for the work was provided by the Louisiana Department of Wildlife and Fisheries. Huy Vu aided in the construction of tables and figures. We appreciate this support and assistance.

LITERATURE CITED

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THOMAS M. SONIAT, (1,2*) NATHAN A. COOPER (2) AND ERIC N. POWELL (3)

(1) Department of Biological Sciences, University of New Orleans, 2000 Lakeshore Drive, New Orleans, LA 70148; (2) Gulf States Center for Environmental Informatics, University of New Orleans, 2045 Lakeshore Drive, New Orleans, LA 70148; (3) Gulf Coast Research Laboratory, University of Southern Mississippi, 703 East Beach Drive, Ocean Springs, MS 39564

(*) Corresponding author. E-mail: tsoniat@uno.edu

DOI: 10.2983/035.038.0214
TABLE 1.
Model equations and parameters.

                Equation                    Variables and comments

Initial number of oysters by size group,    g, oyster size group index
[mathematical expression not reproducible]  R, number of replicates
                                              sampled
                                            [OS.sub.r,g], oyster counts
                                              from data samples for
                                              replicate r of size group
                                              g
                                            [A.sub.r], area sampled
                                              ([m.sup.2]) for replicate
                                              r

Initial cultch mass by cultch type,         c, cultch type index
[mathematical expression not reproducible]  R, number of replicates
                                              sampled
                                            [CS.sub.r,g], cultch mass
                                              (g) from data samples for
                                              replicate r of cultch
                                              type c
                                            [A.sub.r], area sampled
                                              ([m.sup.2]) for replicate
                                              r

Mortality rate of spat and seed oysters,    t, oyster length (mm)
[mathematical expression not reproducible]  t, time
                                            [mo.sub.i], month (1-12)
                                              number corresponding to
                                              simulation time t

Monthly mortality fraction of market-sized  l, oyster length (mm)
oysters,                                    t, time
[mathematical expression not reproducible]  [T.sub.t], temperature
                                              ([degrees]C), at time t
                                            [S.sub.t], salinity, at
                                              time t

Monthly mortality fraction of market-sized  l, oyster length (mm)
oysters,                                    t, time
[mathematical expression not reproducible]

Growth,                                     l, oyster length (mm)
[mathematical expression not reproducible]  t, time
                                            [T.sub.t], temperature
                                              ([degrees]C), at time t
                                            [S.sub.t], salinity, at
                                              time t

Length,                                     g, oyster size group index
[mathematical expression not reproducible]  t, time
                                            [LS.sub.g], original
                                              sampled size (mm) for
                                              size group g

Oyster volume,                              l, oyster length (mm)
[mathematical expression not reproducible]  N, number of oysters

Cultch volume,                              c, cultch type index
[mathematical expression not reproducible]  M, mass of cultch (g)

Shell mass from dead oyster,                l, oyster length (mm)
[mathematical expression not reproducible]

Cultch dissolution fraction (monthly),      c, cultch type index
[mathematical expression not reproducible]

Number of dead oysters (monthly),           g, oyster size group index
[mathematical expression not reproducible]  t, time

Number of oysters,                          g, oyster size group index
[mathematical expression not reproducible]  t, time
                                            [f.sub.se,o](l, t),
                                              effective fishing
                                              fraction of oysters of
                                              length l due to seeding
                                              at time t
                                            [f.sub.sa,o](l, t),
                                              effective fishing
                                              fraction of oysters of
                                              length a due to sacking
                                              at time t

Cultch gain (from oyster mortality),        G, total set of oyster size
[mathematical expression not reproducible]    groups
                                            [C.sub.bs], the cultch type
                                              index corresponding to
                                              oyster shell
                                            c, cultch type index

Cultch mass,                                t, time
[mathematical expression not reproducible]  [f.sub.se,c] (c, t),
                                              effective fishing
                                              fraction of cultch of
                                              type c due to seeding at
                                              time t

TABLE 2.
Model constants and coefficients.

Constant                          Definition

Length
  [L.sub.Seed-Thresh]  Minimum size of seed-sized oyster
  [L.sub.Sack-Thresh]  Minimum size of sack-sized oyster
Mortality
  [m.sub.J,0]          Juvenile mortality coefficient
  [m.sub.J,1]          Juvenile mortality exponent
  [m.sub.A,0]          Adult mortality coefficient
  [m.sub.A,1]          Adult mortality exponent
  [t.sub.avg]          Month of average mortality
Conversions
  [V.sub.Sack]         Oyster sack capacity
  [OPS.sup.A]          Oysters-per-sack coefficient
  [OPS.sub.B]          Oysters-per-sack exponent
  [M.sub.A]            Oyster shell mass coefficient
  [M.sub.B]            Oyster shell mass exponent
Cultch properties                                         Oystershell
  [d.sub.c]            Cultch density                     2,200
  [p.sub.c]            Cultch packing coefficient             0.590
  [r.sub.c]            Cultch annual loss rate                0.1

Constant                          Value

Length
  [L.sub.Seed-Thresh]             25.0
  [L.sub.Sack-Thresh]             75.0
Mortality
  [m.sub.J,0]                      1.203972804
  [m.sub.J,1]                      1.1
  [m.sub.A,0]                      0.510825624
  [m.sub.A,1]                      0.41
  [t.sub.avg]                      6
Conversions
  [V.sub.Sack]                    52.85
  [OPS.sup.A]                      1.767 x [10.sup.8]
  [OPS.sub.B]                     -2.926
  [M.sub.A]                        0.0004
  [M.sub.B]                        2.8213
Cultch properties      Limestone  Clamshell            Hooked mussel
  [d.sub.c]            2,518      2,286                1,667
  [p.sub.c]                0.571      0.425                0.258
  [r.sub.c]                0.01       0.3                  0.8

Constant                             Units

Length
  [L.sub.Seed-Thresh]                  mm
  [L.sub.Sack-Thresh]                  mm
Mortality
  [m.sub.J,0]                          -
  [m.sub.J,1]                          -
  [m.sub.A,0]                          -
  [m.sub.A,1]                          -
  [t.sub.avg]                     Month (1-12)
Conversions
  [V.sub.Sack]                         L
  [OPS.sup.A]                          -
  [OPS.sub.B]                          -
  [M.sub.A]                            -
  [M.sub.B]                            -
Cultch properties      Concrete
  [d.sub.c]            2,285          g/L
  [p.sub.c]                0.531       -
  [r.sub.c]                0.001       -

TABLE 3.
Sack and seed fishing pressures for each CSA, based on recent fishing
pressures (percent in effort/month).

CSA  Sack/Seed  September  October  November  December  January

 1     Sack         0         o        25        25       25
       Seed         0         0       100         0        0
 2     Sack         0         0        25        25       25
       Seed         o         0         0         0        0
 3     Sack         o         0        25        25       25
       Seed         o         0       100         0        0
 4     Sack         0         o         0         0        0
       Seed         0         o         0         0        0
 5     Sack         0         0         0         0        0
       Seed         0         0         O         0        0
 6     Sack         0         0         5         5        5
       Seed         0         o         0         0        0
 7     Sack         o         o        25        25       25
       Seed         0         0         0         0        0

CSA  February  March  April

 1      25        0     0
         0        0     0
 2      25        0     0
         0        0     0
 3      25        0     0
         0        0     0
 4       0        0     0
         0        0     0
 5       0        0     0
         0        0     0
 6       5       80     0
         0      100     0
 7      25        0     0
         0        0     0

TABLE 4.
The proportion (percent) of seed fishing to sack fishing in 2018 for
each CSA.

CSA  Seed  Sack

 1    10     90
 2     0    100
 3    10     90
 4     0      0
 5     0      0
 6    90     10
 7     0    100

TABLE 5.
Mean monthly water temperatures from Eugene Island, central coastal
Louisiana. Data from https://www.currentresults.com/Oceans/Temperature
/louisiana-alabama-average-water-temperature.php##c.

  Month    Temperature ([degrees]C)

January               11
February              12
March                 16
April                 20
May                   24
June                  28
July                  29
August                29
September             28
October               23
November              17
December              13

TABLE 6.
Monthly mean salinities for low-, moderate-, and high-salinity years,
and annual mean salinities (from Melancon et al. 1998).

   Month     Low salinity  Moderate salinity  High salinity

January           9.8            18.3             18.8
February          9.0            15.0             21.8
March             7.3            15.3             20.5
April             6.5            13.8             22.3
May               7.3            12.8             21.8
June              9.0            12.8             17.8
July              5.5            11.3             16.3
August            7.3            11.0             18.5
September         9.0            14.0             19.3
October          11.8            16.0             23.0
November         12.3            16.3             23.8
December         11.5            16.0             25.0
Annual mean       8.8            14.4             20.7

TABLE 7.
Reef location, size (acres), and sustainable harvest estimates for the
2018/2019 season. Location of reefs by CSA/region of POG, and latitude
/longitude. Public Oyster Grounds are in Mississippi Sound (MS), the
Biloxi Marsh (BM), Breton Sound (BS), Hackberry Bay (HB), Barataria Bay
(BB), Terrebonne Bay (TB), the Sister Lake (SI) area, Vermilion Bay
(VB) and Lake Calcasieu (LC). Oyster density (0) is in numbers per
[m.sup.2]. Cultch mass (C) is in g per [m.sup.2]. Harvest of seed and
sack (market-sized) oysters is in sacks. The subscript A indicates
initial conditions, whereas the subscript B indicates post-simulation
conditions. Reefs that are "not fishable" as defined in the text are
indicated. No initial oysters (no init. oysters), no initial substrate
(no init. subst.), and no oysters or substrate (no resource) are
indicated. Simulations can be sustainable with conditions, (Sust.
w/cond.), in which fishing constraints are fulfilled before reaching
the no-net-cultch (NNCL) loss standard or "solved", in which the NNCL
standard is met. Salinity conditions (S) are low, moderate (mod.), or
high as indicated in Table 6. CP, cultch plant; SP, shell plant.

Reef                       Acreage  Latitude  Longitude  [O.sub.A]

CSA 1/MS
  Cabbage                  1,804    30.15306  -89.22556   0.6
  Grand Banks              1,066    30.14778  -89.36028  12.2
  Grand Pass               1,804    30.14278  -89.23972   0
  Grassy                   1,066    30.15     -89.46667   2
  Halfmoon                 1,066    30.11944  -89.43194   0.6
  Millenium                1,066    30.11278  -89.44611   0
  Petit                    1,066    30.09806  -89.47889   0.4
  Round Island 2011 CP       291    30.11974  -89.45672  10.4
CSA 1/BM
  Holmes                   1,592    29.93833  -89.20667   0
  Johnson Bayou              200    30.0875   -89.31083   0
  Martin                   1,592    29.96     -89.20833   0
  Morgan Harbor            2,954    29.79583  -89.32861   0
  Drum Bay                 1,596    29.88861  -89.29194   1.6
  East Karako              1,020    30.02     -89.23389   0
  Three Mile               1,020    30.03917  -89.35278   0.4
  Shell Point                 47    30.02306  -89.35194   6.6
  Turkey Bayou             1,804    30.10472  -89.29861   0
  West Karako              1,020    30.01194  -89.28306   0
CSA 2/BS
  Lonesome 2009 CP           243    29.60803  -89.54012   0
  Battledore                 271    29.46412  -89.42875   0
  Bay Crabe                  511    29.55697  -89.57682   0
  Bay Gardene                632    29.58272  -89.64577   0
  Bay Long                   923    29.50833  -89.59167   0
  Bayou Lost                 275    29.60088  -89.61727   0
  Black Bay                  716    29.59685  -89.5657    0
  California Bay             923    29.51112  -89.56667   0
  Curfew                     715    29.53685  -89.53348   0
  East Bay Crabe             511    29.55665  -89.56982   0
  East Bay Gardene           632    29.58167  -89.62195   0
  East Pelican             1,445    29.49952  -89.52645   0
  East Stone                 829    29.58306  -89.51472   0
  Elephant Pass              202    29.54125  -89.5641    0
  Horseshoe                  829    29.60261  -89.49386   0
  Jessie                     275    29.63502  -89.6182    0
  Lonesome                   715    29.61355  -89.5568    0
  Mangrove Point           1,445    29.479    -89.54004   0
  North Black Bay            829    29.61278  -89.50902   0
  North California Bay       715    29.5279   -89.54102   0
  North Lake Fortuna       1,727    29.6794   -89.48487   0
  South Black Bay            715    29.56033  -89.53443   0
  South Lake Fortuna       1,727    29.6502   -89.50435   0
  Snake                      716    29.63397  -89.56423   0
  Stone                      715    29.57612  -89.54145   0
  Sunrise Point              923    29.49475  -89.56655   0
  Telegraph                  715    29.516    -89.53232   0
  West Bay Crabe             511    29.56522  -89.5866    0
  West Pelican               923    29.50695  -89.54583   0
  Wreck                    4,486    29.56472  -89.48306   0
CSA 3/HB
  BB 2004 CP                  40    29.33028  -89.94      0.2
  North Hackberry 2004 SP     10    29.41722  -90.0325    0
  South Hackberry 2004 SP     25    29.38833  -90.0525    0
  Hackberry 2008 CP           50    29.42528  -90.01528   1.2
  Hackberry 2012 CP          200    29.42007  -90.052     1.2
  Hackberry 2014 CP           30    29.42098  -90.0231    6.2
  Lower Hackberry              5    29.38822  -90.05253   0
  Middle Hackberry             5    29.40169  -90.02917   1.8
  Upper Hackberry              5    29.42164  -90.03069   1.8
CSA 4/TB
  Lake Felicity               40    29.315    -90.44444   0
CSA 5/SI
  Grand Pass                 107    29.25861  -90.93333   1.6
  Junop Bayou De West         34    29.23583  -91.06167   0.2
  Mid SI                      56    29.235    -90.9275    0
  Old Camp                   140    29.21583  -90.94667   0
  Rat Bayou                   34    29.21667  -91.04833   0.2
  South SI 1994 SP           513    29.22472  -90.90889   0
  SI 2004 CP                  82    29.225    -90.91444   1.2
CSA 6/VB
  Bayou Blanc                 15    29.51333  -91.75833   3.4
  Big Charles                 15    29.61417  -91.98694   2
  Dry                         10    29.68639  -91.90194   0
  Highspot                   250    29.49197  -91.75785   4.6
  Indian Point               100    29.61889  -92.00889   1.6
  Lighthouse Point            30    29.57972  -92.03444   3.6
  Middle                      20    29.45278  -91.72389   2.2
  North                       10    29.47917  -91.80778   2.4
  Nickle                     100    29.41939  -91.70775  13
  Rabbit                      15    29.51111  -91.5975    0
  Sally Shoals                 5    29.65444  -91.87111   0
CSA 7/LC
  Calcasieu 2009 CP          295    29.84333  -93.31861   0.2
  Nine Mile                  527    29.885    -93.32694   0
  Big Washout                295    29.85667  -93.33833   1.2
  Chenier                     10    29.84945  -93.28372  17
  Lamberts                   240    29.84121  -93.27682   2.6
  Little Washout             295    29.85028  -93.34083   2.8
  Mid Lake                   295    29.85417  -93.32889   1
  Northeast Rabbit Island    366    29.85694  -93.38222   1.4
  Northwest Rabbit Island    755    29.85935  -93.39211   1.6
  Southeast Rabbit Island    366    29.84306  -93.37556   0.2
  West Cove Transplant       366    29.8475   -93.36972   0
  West Rabbit Island         755    29.84694  -93,395     7.2
  West Cove Central          755    29.85549  -93.40901   3

Reef                       [C.sub.A]  Status             [O.sub.B]

CSA 1/MS
  Cabbage                  2,874      Not fishable       0.2
                                      Not fishable       0.3
                                      Not fishable       0.3
  Grand Banks              4,715      Not fishable       3.7
                                      Not fishable       4.7
                                      Not fishable       5.1
  Grand Pass               1,871      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Grassy                     154      Sust. w/cond.        0
                                      Solved               0
                                      Sust. w/cond.      0.2
  Halfmoon                     0      No init. subst.      0
                                      No init. subst.      0
                                      No init. subst.    0.2
  Millenium                    0      No resources         0
                                      No resources         0
                                      No resources         0
  Petit                        0      No init. subst.      0
                                      No init. subst.      0
                                      No init. subst.    0.1
  Round Island 2011 CP       619      Sust. w/cond.      0.6
                                      Sust. w/cond.      2.1
                                      Sust. w/cond.      4.1
CSA 1/BM
  Holmes                       0      No resources         0
                                      No resources         0
                                      No resources         0
  Johnson Bayou                0      No resources         0
                                      No resources         0
                                      No resources         0
  Martin                       0      No resources         0
                                      No resources         0
                                      No resources         0
  Morgan Harbor                0      No resources         0
                                      No resources         0
                                      No resources         0
  Drum Bay                 1,939      Not fishable       0.3
                                      Not fishable       0.6
                                      Not fishable       0.7
  East Karako              2,052      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Three Mile                 345      Not fishable       0.1
                                      Not fishable       0.2
                                      Not fishable       0.2
  Shell Point              5,546      Solved             0.6
                                      Solved             1.2
                                      Solved             3.2
  Turkey Bayou                43      No init. oysters     0
                                      No finit. oysters    0
                                      No finit. oysters    0
  West Karako              1,076      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
CSA 2/BS
  Lonesome 2009 CP             0      No resources         0
                                      No resources         0
                                      No resources         0
  Battledore                 559      No finit. oysters    0
                                      No finit. oysters    0
                                      No init. oysters     0
  Bay Crabe                    2      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Bay Gardene                103      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Bay Long                   110      No finit. oysters    0
                                      No init. oysters     0
                                      No finit. oysters    0
  Bayou Lost                  48      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Black Bay                   21      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  California Bay               0      No resources         0
                                      No resources         0
                                      No resources         0
  Curfew                     451      No init. oysters     0
                                      No init. oysters     0
                                      No finit. oysters    0
  East Bay Crabe               0      No resources         0
                                      No resources         0
                                      No resources         0
  East Bay Gardene           129      No init. oysters     0
                                      No finit. oysters    0
                                      No finit. oysters    0
  East Pelican               101      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  East Stone                  55      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Elephant Pass              422      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Horseshoe                  152      No finit. oysters    0
                                      No init. oysters     0
                                      No init. oysters     0
  Jessie                     473      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Lonesome                    23      No finit. oysters    0
                                      No finit. oysters    0
                                      No finit. oysters    0
  Mangrove Point               0      No resources         0
                                      No resources         0
                                      No resources         0
  North Black Bay              0      No resources         0
                                      No resources         0
                                      No resources         0
  North California Bay         0      No resources         0
                                      No resources         0
                                      No resources         0
  North Lake Fortuna          97      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  South Black Bay              0      No resources         0
                                      No resources         0
                                      No resources         0
  South Lake Fortuna           0      No resources         0
                                      No resources         0
                                      No resources         0
  Snake                        9      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Stone                      372      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Sunrise Point                4      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Telegraph                    0      No resources         0
                                      No resources         0
                                      No resources         0
  West Bay Crabe              20      No init. oysters     0
                                      No init. oysters     0
                                      No init. Oysters     0
  West Pelican                 0      No resources         0
                                      No resources         0
                                      No resources         0
  Wreck                      341      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
CSA 3/HB
  BB 2004 CP               1,760      Not fishable         0
                                      Not fishable         0
                                      Not fishable       0.1
  North Hackberry 2004 SP     76      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  South Hackberry 2004 SP  1,074      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Hackberry 2008 CP        1,435      Solved             0.1
                                      Solved             0.2
                                      Not fishable       0.6
  Hackberry 2012 CP        2,056      Not fishable       0.1
                                      Solved               0
                                      Not fishable       0.4
  Hackberry 2014 CP        3,229      Solved             0.3
                                      Solved             1.4
                                      Solved             2.5
  Lower Hackberry              0      No resources         0
                                      No resources         0
                                      No resources         0
  Middle Hackberry           600      Sust. w/Cond.        0
                                      Solved               0
                                      Sust. w/Cond.      0.1
  Upper Hackberry            151      Sust. w/Cond.        0
                                      Sust. w/Cond.      0.1
                                      Sust. w/Cond.      0.6
CSA 4/TB
  Lake Felicity                0      No resources         0
                                      No resources         0
                                      No resources         0
CSA 5/SI
  Grand Pass               1,087      Not fishable       0.2
                                      Not fishable       0.4
                                      Not fishable       0.7
  Junop Bayou De West        664      Not fishable         0
                                      Not fishable       0.1
                                      Not fishable       0.1
  Mid SI                     142      No Mit, oysters      0
                                      No Mit. oysters      0
                                      No init. oysters     0
  Old Camp                   729      No init. oysters     0
                                      No init. oysters     0
                                      No init. Oysters     0
  Rat Bayou                  134      Not fishable         0
                                      Not fishable       0.1
                                      Not fishable       0.1
  South SI 1994 SP             0      No resources         0
                                      No resources         0
                                      No resources         0
  SI 2004 CP               1,641      Not fishable       0.3
                                      Not fishable       0.6
                                      Not fishable       0.6
CSA 6/VB
  Bayou Blanc              4,267      Not fishable       0.8
                                      Not fishable       1.9
                                      Not fishable       1.9
  Big Charles              2,543      Not fishable       0.3
                                      Not fishable       0.5
                                      Not fishable       1.1
  Dry                        851      No init. oysters     0
                                      No Mit. oysters      0
                                      No init. oysters     0
  Highspot                 2,218      Solved             0.7
                                      Not fishable       1.7
                                      Not fishable       2.6
  Indian Point             3,186      Not fishable       0.2
                                      Not fishable       0.2
                                      Not fishable       0.9
  Lighthouse Point         3,466      Not fishable       0.5
                                      Not fishable       0.8
                                      Not fishable       1.9
  Middle                     326      Solved             0.2
                                      Solved             0.9
                                      Not fishable       1.3
  North                    1,308      Not fishable       0.5
                                      Not fishable       1.2
                                      Not fishable       1.4
  Nickle                   3,062      Solved             1.7
                                      Solved             4.4
                                      Not fishable         7
  Rabbit                   2,360      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  Sally Shoals             2,059      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
CSA 7/LC
  Calcasieu 2009 CP        1,474      Not fishable         0
                                      Not fishable         0
                                      Not fishable       0.1
  Nine Mile                    0      No resources         0
                                      No resources         0
                                      No resources         0
  Big Washout              1,532      Not fishable       0.1
                                      Not fishable         0
                                      Not fishable       0.3
  Chenier                  4,137      Sust. w/cond.      0.1
                                      Sust. w/cond.      1.2
                                      Sust. w/cond.      5.6
  Lamberts                   914      Sust. w/cond.        0
                                      Solved               0
                                      Sust. w/Cond.      0.3
  Little Washout             826      Solved             0.2
                                      Solved             0.3
                                      Sust. w/cond.      1.2
  Mid Lake                   932      Not fishable       0.1
                                      Solved               0
                                      Not fishable       0.2
  Northeast Rabbit Island  1,378      Not fishable       0.1
                                      Solved             0.1
                                      Not fishable       0.3
  Northwest Rabbit Island    345      Sust. w/cond.        0
                                      Sust. w/cond.        0
                                      Sust. w/cond.      0.1
  Southeast Rabbit Island    718      Not fishable         0
                                      Not fishable         0
                                      Not fishable       0.1
  West Cove Transplant       902      No init. oysters     0
                                      No init. oysters     0
                                      No init. oysters     0
  West Rabbit Island       1,800      Sust. w/cond.        0
                                      Solved             0.3
                                      Sust. w/cond.      1.6
  West Cove Central          405      Sust. w/cond.        0
                                      Solved               0
                                      Sust. w/cond.      0.1

Reef                       [C.sub.B]  [H.sub.SE]  [H.sub.SA]  S

CSA 1/MS
  Cabbage                  2,594          0            0      Low
                           2,588          0            0      Mod.
                           2,588          0            0      High
  Grand Banks              4,514          0            0      Low
                           4,413          0            0      Mod.
                           4,338          0            0      High
  Grand Pass               1,684          0            0      Low
                           1,684          0            0      Mod.
                           1,684          0            0      High
  Grassy                     218      3,675       14,685      Low
                             154      3,232       24,854      Mod.
                             281      3,412        7,000      High
  Halfmoon                     9        512        3,693      Low
                              16        452        2,783      Mod.
                              17        305          547      High
  Millenium                    0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Petit                       11        410        2,523      Low
                               4        451        3,366      Mod.
                              21        349          667      High
  Round Island 2011 CP       717      3,208       13,289      Low
                             656      3,022       10,877      Mod.
                             745      2,449        1,998      High
CSA 1/BM
  Holmes                       0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Johnson Bayou                0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Martin                       0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Morgan Harbor                0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Drum Bay                 1,844          0            0      Low
                           1,832          0            0      Mod.
                           1,800          0            0      High
  East Karako              1,847          0            0      Low
                           1,847          0            0      Mod.
                           1,847          0            0      High
  Three Mile                 325          0            0      Low
                             314          0            0      Mod.
                             313          0            0      High
  Shell Point              5,546        441          783      Low
                           5,546        427          486      Mod.
                           5,546        107           20      High
  Turkey Bayou                30          0            0      Low
                              30          0            0      Mod.
                              30          0            0      High
  West Karako                929          0            0      Low
                             929          0            0      Mod.
                             929          0            0      High
CSA 2/BS
  Lonesome 2009 CP             0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Battledore                 502          0            0      Low
                             502          0            0      Mod.
                             502          0            0      High
  Bay Crabe                    1          0            0      Low
                               1          0            0      Mod.
                               1          0            0      High
  Bay Gardene                 82          0            0      Low
                              82          0            0      Mod.
                              82          0            0      High
  Bay Long                    99          0            0      Low
                              99          0            0      Mod.
                              99          0            0      High
  Bayou Lost                  42          0            0      Low
                              42          0            0      Mod.
                              42          0            0      High
  Black Bay                   19          0            0      Low
                              19          0            0      Mod.
                              19          0            0      High
  California Bay               0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Curfew                     400          0            0      Low
                             400          0            0      Mod.
                             400          0            0      High
  East Bay Crabe               0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  East Bay Gardene           111          0            0      Low
                             111          0            0      Mod.
                             111          0            0      High
  East Pelican                90          0            0      Low
                              90          0            0      Mod.
                              90          0            0      High
  East Stone                  50          0            0      Low
                              50          0            0      Mod.
                              50          0            0      High
  Elephant Pass              380          0            0      Low
                             380          0            0      Mod.
                             380          0            0      High
  Horseshoe                  137          0            0      Low
                             137          0            0      Mod.
                             137          0            0      High
  Jessie                     426          0            0      Low
                             426          0            0      Mod.
                             426          0            0      High
  Lonesome                    18          0            0      Low
                              18          0            0      Mod.
                              18          0            0      High
  Mangrove Point               0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  North Black Bay              0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  North California Bay         0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  North Lake Fortuna          87          0            0      Low
                              87          0            0      Mod.
                              87          0            0      High
  South Black Bay              O          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  South Lake Fortuna           0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Snake                        8          0            0      Low
                               8          0            0      Mod.
                               8          0            0      High
  Stone                      324          0            0      Low
                             324          0            0      Mod.
                             324          0            0      High
  Sunrise Point                4          0            0      Low
                               4          0            0      Mod.
                               4          0            0      High
  Telegraph                    0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  West Bay Crabe              15          0            0      Low
                              15          0            0      Mod.
                              15          0            0      High
  West Pelican                 0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Wreck                      305          0            0      Low
                             305          0            0      Mod.
                             305          0            0      High
CSA 3/HB
  BB 2004 CP               1,756          0            0      Low
                           1,757          0            0      Mod.
                           1,745          0            0      High
  North Hackberry 2004 SP     68          0            0      Low
                              68          0            0      Mod.
                              68          0            0      High
  South Hackberry 2004 SP  1,017          0            0      Low
                           1,017          0            0      Mod.
                           1,017          0            0      High
  Hackberry 2008 CP        1,435         41           50      Low
                           1,435         33           41      Mod.
                           1,412          0            0      High
  Hackberry 2012 CP        2,039          0            0      Low
                           2,056          4            7      Mod.
                           2,007          0            0      High
  Hackberry 2014 CP        3,229        378          816      Low
                           3,229        302          750      Mod.
                           3,229        360          168      High
  Lower Hackberry              0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Middle Hackberry           651         40          114      Low
                             600         21          193      Mod.
                             754         38           60      High
  Upper Hackberry            180         14           59      Low
                             158         14           66      Mod.
                             214         11           14      High
CSA 4/TB
  Lake Felicity                0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
CSA 5/SI
  Grand Pass               1,062          0            0      Low
                           1,061          0            0      Mod.
                           1,006          0            0      High
  Junop Bayou De West        607          0            0      Low
                             600          0            0      Mod.
                             599          0            0      High
  Mid SI                     129          0            0      Low
                             129          0            0      Mod.
                             129          0            0      High
  Old Camp                   656          0            0      Low
                             656          0            0      Mod.
                             656          0            0      High
  Rat Bayou                  130          0            0      Low
                             123          0            0      Mod.
                             122          0            0      High
  South SI 1994 SP             0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  SI 2004 CP               1,584          0            0      Low
                           1,556          0            0      Mod.
                           1,553          0            0      High
CSA 6/VB
  Bayou Blanc              3,825          0            0      Low
                           3,719          0            0      Mod.
                           3,708          0            0      High
  Big Charles              2,399          0            0      Low
                           2,375          0            0      Mod.
                           2,308          0            0      High
  Dry                        748          0            0      Low
                             748          0            0      Mod.
                             748          0            0      High
  Highspot                 2,218        411            3      Low
                           2,147          0            0      Mod.
                           2,046          0            0      High
  Indian Point             2,976          0            0      Low
                           2,967          0            0      Mod.
                           2,898          0            0      High
  Lighthouse Point         3,329          0            0      Low
                           3,306          0            0      Mod.
                           3,179          0            0      High
  Middle                     326        123            2      Low
                             326         42            0      Mod.
                             315          0            0      High
  North                    1,260          0            0      Low
                           1,194          0            0      Mod.
                           1,164          0            0      High
  Nickle                   3,062      3,146           38      Low
                           3,062      1,484            3      Mod.
                           2,993          0            0      High
  Rabbit                   1,962          0            0      Low
                           1,962          0            0      Mod.
                           1,962          0            0      High
  Sally Shoals             1,583          0            0      Low
                           1,583          0            0      Mod.
                           1,583          0            0      High
CSA 7/LC
  Calcasieu 2009 CP        1,473          0            0      Low
                           1,473          0            0      Mod.
                           1,462          0            0      High
  Nine Mile                    0          0            0      Low
                               0          0            0      Mod.
                               0          0            0      High
  Big Washout              1,477          0            0      Low
                           1,498          0            0      Mod.
                           1,454          0            0      High
  Chenier                  4,485          0        1,078      Low
                           4,377          0        1,158      Mod.
                           4,795          0          291      High
  Lamberts                   974          0        5,808      Low
                             914          0        8,546      Mod.
                           1,083          0        2,802      High
  Little Washout             826          0        4,074      Low
                             826          0        3,555      Mod.
                             829          0          661      High
  Mid Lake                   932          0            0      Low
                             932          0          644      Mod.
                             921          0            0      High
  Northeast Rabbit Island  1,359          0            0      Low
                           1,378          0          781      Mod.
                           1,329          0            0      High
  Northwest Rabbit Island    453          0       14,029      Low
                             350          0       23,988      Mod.
                             536          0        7,593      High
  Southeast Rabbit Island    660          0            0      Low
                             660          0            0      Mod.
                             649          0            0      High
  West Cove Transplant       809          0            0      Low
                             809          0            0      Mod.
                             809          0            0      High
  West Rabbit Island       1,908          0       47,857      Low
                           1,800          0       63,158      Mod.
                           2,150          0       20,035      High
  West Cove Central          535          0       18,301      Low
                             405          0       31,509      Mod.
                             648          0        9,713      High

TABLE 8.
Sustainable harvests of seed ([H.sub.SE]) and sack oysters ([H.sub.SA])
in sacks, by CSA and low-, moderate-, and high-salinity regime (S), as
defined in Table 6. Reefs without initial substrate (Table 7) are not
included. Statewide sums (total) are given by salinity regime.

 CSA   [H.sub.SE]  [H.sub.SA]  S

  1     7,324      28,757      Low
        6,681      36,217      Mod.
        5,968       9,018      High
  2         0           0      Low
            0           0      Mod.
            0           0      High
  3       473       1,039      Low
          374       1,057      Mod.
          409         242      High
  4         0           0      Low
            0           0      Mod.
            0           0      High
  5         0           0      Low
            0           0      Mod.
            0           0      High
  6     3,680          43      Low
        1,526           3      Mod.
            0           0      High
  7         0      91,147      Low
            0      133339      Mod.
            0      41,095      High
Total  11,477      120986      Low
        8,581      170616      Mod.
        6,377      50,355      High
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Article Details
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Author:Soniat, Thomas M.; Cooper, Nathan A.; Powell, Eric N.
Publication:Journal of Shellfish Research
Geographic Code:1U7LA
Date:Aug 1, 2019
Words:9709
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