Source: Virginia Marine Resource Commission https://webapps.mrc.virginia.gov/public/maps/chesapeakebay_map.php
Chesapeake Bay is the largest estuary in the United States. The bay is in the temperate climate zone, and its waters are contained entirely within the mid-Atlantic states of Maryland and Virginia. The bay stretches 200 miles (321 km) from its northern end in Maryland to its mouth near Norfolk, Virginia. It is relatively narrow, only 35 miles (56 km) at its widest point at the mouth of the Potomac, and relatively shallow, with an average depth of 21 feet (6.4 m). Water flows into the bay from five major tributary rivers: the Susquehanna, the Potomac, the Rappahannock, the James and the York. Numerous streams also feed into the bay. Water mixes with the Atlantic Ocean at the relatively narrow inlet at the south end of the bay. This area, referred to as Hampton Roads, includes a major port and U.S. Navy base. The area is shown in Figure 15.1.
The watershed covers 64,000 square miles (165,760 km2) in seven states and has a population of more than 17 million people (Chesapeake Bay Program 2015a.) This is a 70 percent increase from 10 million in the early 1960s. The two counties along the mouth of the Rappahannock – Lancaster and Middlesex – had a combined population of 20,369 in 2010. This is only a 25 percent increase from the 16,295 residents in 1960. The counties are rural and distant from the major urban centers of Washington, DC, and Richmond. Water quality in the case study area thus is most heavily influenced by population and economic activity in the rest of the watershed. The labor force in the public fishery is more heavily drawn from nearby counties. Private cultivation in the area is primarily found along the shorelines.
Shallow waters (less than 3 meters depth) and tidal flats can be found along the shorelines of the bay and its rivers. These provide habitat for birds, submerged aquatic vegetation, finfish and shellfish. Farther out are three-dimensional reef structures usually made up of densely packed oyster shell. These provide settling grounds for oyster larvae and habitat for other aquatic species, including finfish and blue crabs. As filter feeders, oysters improve water clarity and accelerate the cycling and removal of nutrients. Beyond the shorelines are open waters which also contain oyster reefs but are too deep for submerged aquatic vegetation (Chesapeake Bay Program 2015b).
Source: Virginia Marine Resource Commission https://webapps.mrc.virginia.gov/public/maps/chesapeakebay_map.php
Water temperature can vary widely throughout the year. Because the bay is relatively shallow, it does not store heat over time so temperatures can fluctuate – ranging from 34°F (1.1°C) in the winter to 84°F (28.8°C) in the summer. The temperatures in the shallower waters vary more than in the deeper open waters (Chesapeake Bay Program 2015b). Salinity levels can also vary widely within the bay; higher in the south end where the mouth of the bay interacts with the ocean, and lower in the northern waters and the mouths of the rivers along the western shore. This variation in salinity affects both the range of oyster habitat and the spread of disease. Adult oysters grow best with salinity levels above 14 psu (Chesapeake Bay Program 2015c). Unfortunately, the prevalence of disease and some predators are also positively associated with salinity levels.
Historically the bay has been one of the most productive estuaries in the United States. It supports populations of anadromous fish, including menhaden (Brevoortia tyrannus), shad (Alosa sapidissima) and striped bass (Morone saxatilis). It has long been renowned for its blue crabs (Callinectes sapidus) and oysters. Harvesters of the bay’s bounty are traditionally referred to as watermen. They are almost exclusively male. Most live along or near the shorelines, allowing them to work on the water during the day and return home each evening. Their vessels are usually equipped to harvest a variety of products, oysters and blue crabs in particular. Oyster harvest methods include hand tonging, scraping and dredging. The vessels range in size, from 23 ft (7 m) to 47 ft (14 m) according to one survey and are powered by inboard gasoline motors (Wieland 2006). While on the water, a vessel may have one to three workers on board. Watermen may also work in farming, construction and assisting with aquaculture operations.
The boom time for the Virginia oyster fishery was the later part of the nineteenth century when reported landings ranged from 4 (344 L) to 8 (688 L) million Virginia bushels per year (one Virginia bushel is equivalent to 344 liters in volume). In the later part of the century, the subaqueous grounds in the bay that were capable of supporting a wild population of oysters were set aside as public grounds open to all harvesters. In Virginia, the remaining areas were made available for leasing for private cultivation. The intense effort to harvest oysters from the public grounds, in particular, the use of dredges dragged along the bottom, damaged the oyster reefs that had developed over centuries. Production during the early part of the twentieth century fell into the range of 2 (172 L) to 4 (344 L) million bushels per year. In the early 1960s two diseases, MSX and Dermo, arrived in the bay decimating populations on both private and public grounds. Initially they were largely restricted to the high-salinity portions of the bay, which are primarily in Virginia waters. Some researchers cite evidence that suggests the development of MSX tolerance in the extant population and Dermo may now be the major cause of disease mortality (Mann and Powell 2007). Both diseases allow for some survival until oysters are mature enough to reproduce and attain market size, usually the third year, but few survive beyond then. By 2000 harvest from the public grounds was near zero, as shown in Figure 15.2. By 2013 with state-sponsored restoration of the public grounds, the harvest from these was up to over 200,000 bushels (9,840,000 L). With the emergence of new cultivation techniques used by private growers, their harvest in 2013 was close to 300,000 bushels (14,760,000 L) (Hudson and Murray 2015).
The revival of private production of oysters has been spurred, in part, by the development of hatcheries and off-bottom cultivation techniques. The development of private oyster hatcheries has given private producers an alternative to dependence upon seed stock harvested from public grounds and provided oyster growers with faster-growing and disease-resistant stocks. Over 90 percent of these are triploids. Triploids come from mating a tetraploid oyster – an oyster with four sets of chromosomes – with a typical diploid oyster with two sets of chromosomes (Virginia Sea Grant News May 15 2013). Triploids are favored by private growers because they cannot reproduce; rather their energy is diverted into a better meat yield, particularly in the summer months when normal oysters are spawning and therefor meat yield is poor (Congrove et al. 2009; Virginia Institute of Marine Science 2009). Higher growth rates allow triploid oysters to reach a market size in less than two years. The hatchery-produced larvae are allowed to set on either shell, becoming spat-on-shell, or on ground-up shell (cultchless setting), becoming single-seed oysters. The spat-on-shell is cultivated by placing it on the bottom of privately leased grounds. This is the traditional, extensive type of cultivation, starting with hatchery-produced seed (Hudson and Murray 2015). The oysters tend then to be clumped together. When harvested, these are destined primarily for the shucking houses. In contrast the single-seed oysters are raised off the bottom in containers. These may be racks sitting on legs on the bottom or in float cages. This intensive type of cultivation reduces losses due to predation, disease and siltation. These oysters are sold into the raw bar trade to be consumed on the half shell. Although oysters raised off bottom for the raw bar trade command a much higher price, their production is much more labor and capital intensive than bottom cultivation. The planting of spat-on-shell uses less labor and more traditional harvesting methods (Hudson and Murray 2015).
The oyster grounds were essentially an open-access resource until the late nineteenth century. The destruction of the oyster reefs from the intense harvesting, as well as the success of oyster cultivation in France, led scientists to advocate for the private leasing of the bay’s bottom. Watermen, accustomed to taking naturally growing oysters, opposed setting aside bottom space for private cultivation. In Virginia, a compromise was reached in which grounds with natural oyster beds were set aside as a public fishery, leaving other areas available for leasing. Lt. John B. Baylor of the U.S. Navy conducted a survey to delineate the area to be set aside for the public fishery, now known as the Baylor grounds (Santopietro and Shabman 1992). The Virginia Constitution as amended in 1902 guarantees that the natural oyster beds, rocks and shoals be reserved for public use. Private individuals or companies could lease the remaining areas from the state, could improve the grounds with hard substrate (usually using old oyster shell) and plant small seed oysters harvested from the public grounds. Private leaseholders are free to harvest using any equipment and in any season. In Virginia no limits on total leaseholds were established so some oyster growers planted thousands of acres. The number of acres leased per year in Virginia has varied from 90,000 to 139,000 acres (364–563 km2), with 118,000 acres (478 km2) under lease in 2015. Historically, private production of oysters far exceeded production from the public grounds until losses from oyster diseases deterred private investment. Production from private leases is once again greater than production from public grounds, as leaseholders have been investing capital in oyster propagation. With a 5 (0.02 km2) acre limit on leaseholds in Maryland, private production did not expand as it did in Virginia (Santopietro and Shabman 1992).
Harvesting from the public grounds has usually been limited to less efficient gear types, because there is no limit on how many individuals may harvest. Often harvest was limited to hand-held tongs – which severely limits the harvest per individual waterman and per vessel. Dredging by sail or motorized vessels has been permitted on a limited basis. More recently, a new type of harvesting technology has appeared – scrapes. These are similar to, but smaller than, the dredges and they are more efficient than the traditional hand tongs.
Governance of the oyster and other fisheries in Virginia waters is primarily hierarchical. Authority is vested by the state in the Virginia Marine Resources Commission (VMRC). Because the bay is entirely within state borders and shellfish do not migrate, federal agencies have little authority over shellfish management. The VMRC commissioners are appointed by the governor of the Commonwealth of Virginia and typically include watermen, representatives from the fishing industry, recreational fishers and economic development officials. Thus, the watermen and seafood industries have input into fishery management. VMRC has a staff of professionals who oversee management of habitat and fisheries and enforcement of promulgated regulations.
The VMRC promulgates rules and regulations for management of the public oyster grounds. Current management strategies are aimed at balancing the preservation of the population and the restoration of a viable commercial oyster fishery (Eastern Oyster Biological Review Team 2007). These strategies were designed to protect the natural populations in areas where harvest is allowed through the establishment of open seasons, gear restrictions, culling requirements and daily catch limits. For example, the season might be set at 60 days, effort limited to hand tongs and scrapes, daily catch limited to a maximum of 8 bushels (393 L) per worker and a cull requirement imposed to return all oysters over 4 inches (10.2 cm) as these survivors could be disease resistant. Other areas are demarcated as sanctuaries, where breeding populations of oysters are protected and harvesting prohibited. Additionally, public funding is provided to VMRC for the maintenance and restoration of the public grounds. VMRC also manages the leasing for private growing and promulgates regulations regarding some aspects of private cultivation primarily related to structures and boundaries. More than 118,000 acres (478 km2) are currently under lease, and 800 oyster aquaculturists are licensed.
VMRC’s restoration of the substrate of the public grounds usually entails ‘shelling’, which is the placement of oyster shell (cultch) on areas likely to attract the settlement of oyster larvae. These are usually areas with an existing layer of shell on the bottom. The shell structure of oyster reefs deteriorates over time due to the shortened lifespan induced by disease, predation and sedimentation, thus necessitating replenishment (Powell et al. 2012). The Virginia Oyster Heritage Program was initiated in 1999 by the Virginia Coastal Zone Management Program to bring state, federal, non-governmental and private industry partners together to increase the natural oyster population in the state (Virginia Department of Environmental Quality 2012). Though federal authorities do not have any responsibility for management of the oyster fishery, the U.S. Army Corps of Engineers (USACE) has been involved in oyster habitat restoration projects. VMRC and USACE have invested in reef construction and shell replenishment on public grounds to establish oyster sanctuary bars in various parts of the bay. The National Oceanic and Atmospheric Administration (NOAA) also helps fund oyster restoration. A non-governmental organization, the Chesapeake Bay Foundation, is a voice for environmental concerns. It also funds sanctuary restoration projects and promotes oyster gardening programs by shoreline residents (Chesapeake Bay Foundation 2015). The objectives are to improve water quality through the water filtration services of the oysters and to hopefully find disease-resistant or -tolerant oysters for further breeding.
The Virginia oyster fishery and governance systems are supported by a variety of state and federally funded scientific efforts and organizations. For example, the Virginia Institute of Marine Sciences (VIMS) is publicly funded with the mission to conduct interdisciplinary research in coastal zone and estuarine science, educate the public and provide advisory services to policymakers and industry. It is also the graduate school in marine science for the College of William and Mary. VIMS operates an oyster breeding effort aimed at developing oysters that are disease resistant and grow to market size more quickly. This effort includes an oyster hatchery run by the Aquaculture Genetics and Breeding Technology Center. The center provides broodstock bred for disease resistance at various salinities to oyster hatcheries (Virginia Institute of Marine Science 2015).
The oyster fishery in the Chesapeake Bay has faced environmental and market stresses, especially in the last four decades.
The diseases afflicting oyster populations in mid-to-high salinity portions of the bay since the early 1960s result in high rates of mortality in the third year of life; few oysters are found that survive longer. Oysters can reproduce before their third year, so most of the offspring are just as susceptible to the disease as the adults.
Some sedimentation has always occurred as the rivers carry runoff soil (Environmental Protection Agency 2003). Increasing population and land development in the watershed is believed to have increased runoff and sediment loads. Increasing levels of sedimentation can smother existing shellfish and reduce the attractiveness of the substrate for larvae settlement. Runoff and discharges from treatment plants and non-point sources have also led to nutrient enrichment primarily along the tributary rivers. The consequent algae blooms and low levels of dissolved oxygen (DO) create dead zones which threaten fisheries and submerged aquatic vegetation. The low DO problem appears worse in deeper water portions of the central bay, which are mostly public grounds (Environmental Protection Agency 2003). Oysters cannot tolerate low DO for long, so this problem primarily affects watermen harvesting the public grounds.
Climate change may also begin having an impact on oyster production due to sea level rise and higher precipitation events which reduce salinities below tolerance levels. Higher carbon levels may also lower pH levels, thereby making it more difficult for oysters and other shellfish to produce calcium carbonate (Environmental Protection Agency 2014). The impacts may be more focused on private production, which occurs closer to shorelines and in less saline waters, particularly the intertidal portions of the tributary rivers and streams.
An increase in the price per bushel of oysters, caused in part by the decline in harvests from the Gulf of Mexico states following hurricanes Katrina and Rita in 2005 and the BP oil spill in 2010, has provided further economic incentive for watermen to seek oysters from the public grounds. Virginia now exports oysters to these areas ensuring that at present no market glut exists even at the start of the season. The Gulf states’ fishery has been slow to return to production as compensation payments from the BP oil spill allow for taking more time off; the return of effort has been slower than that following Katrina and Rita, when no compensation payments were made.
The adoption of scrapes, which increase labor productivity and hence the harvest per unit of effort applied, puts more pressure on the oyster populations on the public grounds. With the use of scrapes the watermen can get a decent harvest even with a lower density of oysters on the bottom. Scrapes were first allowed only in the public grounds of Virginia in 2002. A scrape can easily be adapted to smaller vessels and uses hydraulic winches. Many vessels already are equipped with these winches for use with other types of gear. The greater level of effort with the new harvesting equipment is also thought to have resulted in the more rapid deterioration of the hard substrate, particularly in those areas shelled by the state. The act of harvesting breaks up and disperses the shell remaining on the bars on the bottom. The material being brought up during harvesting includes the hard substrate. The shell is culled but is not always replaced on to good bottom; rather it is spread out around the areas open to harvest. Thus the shell planted to regenerate productivity is disappearing more rapidly on the harvested areas than the rate caused by natural deterioration.
Good recruitment on the public grounds in the Rappahannock in 2010 and 2012 found in surveys by one of the authors resulted in increases in the quantities of market-sized oysters three years out (e.g. 2013, 2014 and 2015). Entrants at the start of the season found oysters plentiful enough that they could harvest the daily limit early and use the time saved for other purposes. However, poor recruitment in 2011, 2013 and 2014 will result in lower quantities of market-sized oysters and will not be sufficient to support current harvest efforts. Production on the public grounds, which goes primarily to the shucking industry, thus will likely fall to 50 percent to 70 percent of current levels as the effects of good spat years and high prices diminish.
A poorly understood decline in the blue crab population means that watermen will reallocate their time to harvesting oysters from the public grounds. The commercial blue crab harvest in Virginia decreased by 24 percent in 2013 from the previous year. The bay-wide blue crab harvest was one of the lowest recorded in the previous 25 years (Chesapeake Bay Stock Assessment Committee 2014). This loss in the blue crab harvest may also encourage more private oyster growing activity. To incentivize this, the VMRC has been using federal blue crab disaster funds to subsidize the planting of spat on shell by watermen on leased grounds (Virginia Marine Resources Commission 2013). Regulations and limits on licensing for blue crabs further ensure that effort in the blue crab fishery will be displaced and people will seek opportunities in other fisheries. More watermen have been observed turning to oyster harvesting earlier than they might otherwise, given the problems in the blue crab fishery.
Recent high prices, good spat set, movement of effort out of the blue crab harvest and the use of scrapes have resulted in overcapitalization in the public grounds fishery. Although VMRC limits the number of days in the open season and limits daily catch per person, the total number of licensed entrants is not restricted. James Wesson, one of the authors, has observed that the number of harvesting vessels has increased several-fold in the last several years, to around 100 boats per day on oyster beds within a single rotation area. Many of the new entrants have no experience in oyster harvesting. To make the most of their time engaged in harvesting, watermen have begun to tow their boats to entry points close to the open grounds rather than traveling by water. This is feasible given the characteristics of this fishery. The overcrowding with the increase in vessels operating over opened public grounds often results in boats interfering with each other’s harvesting efforts. These stressors on the public ground fishery may mean that the current upward trend in harvests and revenue will not be sustainable.
In an effort to protect areas from overfishing and to restore naturally occurring oyster grounds, state and federal authorities have established oyster sanctuaries. The oyster population that existed before the heavy harvesting pressures in the mid-to-late nineteenth century is estimated to have filtered all the water in the bay in as little as three days (Newell 1988). Thus one option for reducing nutrient enrichment and other pollutants is seen to be an increase in the oyster population. Oyster restoration programs are often advocated on the basis of restoring ecosystem services like filtration, aquatic habitat and shoreline protection, rather than production for market. Their efforts in this regard have raised public awareness of the non-market benefits of increasing the oyster population in the bay, and thus pressure on policymakers to do more to establish and maintain oyster sanctuaries dedicated to promoting the growth of oysters protected from harvesting. The USACE and the VMRC have both invested in the establishment of oyster sanctuaries throughout the Virginia portion of the bay (Virginia Department of Environmental Quality 2012). The price of natural cultch, whether coming from oyster shucking or stocks of fossilized shell, has been rising significantly in recent years, making these efforts increasingly expensive.
Over time, the return of private cultivation of oysters may take substantial harvesting pressure off of the public grounds because of an increase in the demand for labor as production expands. On-bottom cultivation still requires labor to plant shell and seed and then harvest the mature oysters. Off-bottom cultivation techniques (e.g. floating pens) may provide other employment opportunities for watermen and may attract potential younger entrants away from harvesting public grounds to oyster farming instead (Rappahannock Oyster Company – About Us 2015).
The program for restoration of the public grounds at the mouth of the Rappahannock River was initiated by the Commonwealth of Virginia in 2000. The program mostly consists of state shell replenishment investments in specifically designated public grounds. Restoration of the grounds at the mouth of the river began with a repletion program of a 1.2 km2 area involving the intensive shelling of 29 surrounding bars using oyster shell from shucking houses and dredged from fossil reserves. These bars cover an area equal to 300 acres (1.21 km2). The Virginia Coastal Zone Management Program provided some of the initial funding. Other funds came from the VMRC, U.S. Army Corps of Engineers and NOAA. The area was selected for restoration because the water is shallow enough to avoid the possible negative impact of low DO levels (anoxia) in the summer months. Nonetheless, the area is subject to freshets, inflows of low-saline water from fresh water sources. Freshets (depending on how low the salinity falls) and anoxia both result in poor recruitment and smaller oyster populations. In some circumstances freshets can benefit oyster growth, particularly by reducing predator populations and MSX mortality.
In 2002 commercial harvesters requested that VMRC open some of the restored areas in the Rappahannock River to harvest. The area opened included 13 of the shelled bars, covering 145 acres (0.59 km2). The harvest that year totaled a reported 13,773 bushels (41,442,957 L). For the following years, harvest on open areas was much smaller: 1,536 bushels (4,621,824 L) in 2003 and 7,190 bushels (21,634,710 L) in 2004. In 2006 a request was made to open additional areas but was not granted. To alleviate the state from having to respond to ad hoc annual requests for opening public grounds, an oyster management plan was developed for the mouth of the Rappahannock by the Virginia Oyster Heritage Program (VOHP) and recommended to the VMRC on August 28, 2007 (VOHP 2007). A Blue Ribbon Oyster Panel also made recommendations to the VMRC regarding oyster restoration strategies that support the type of policies recommended by the VOHP (Blue Ribbon Oyster Panel 2007). These plans were approved by VMRC in August 2007. The management strategy allows for rotational commercial harvest from some of these grounds while maintaining the development of a potentially disease-tolerant broodstock population in non-harvested sanctuaries.
The plan divides the region into six areas as shown in Figure 15.3. Each area contains broodstock sanctuaries, which are not harvested. Bars in two areas are opened to harvest each year. Following a harvest, the region is closed for a period of three years to allow the next set of oysters to grow to market size. VMRC purchases shell and pays for its distribution over the sanctuary and harvest areas to replenish the substrate lost to sedimentation, predation and culling. New shell is placed whenever the exiting stock of shell falls below 5 liters per square meter on the harvest grounds. This target is equivalent to 10,118 bushels (30,445,062 L) of shell over 25 acres (0.1 km2). Given the initial level of shell of 10 liters per square meter when the program began (20,234 bushels [608,841,106 L] over 25 acres [0.1 km2]) and current shell deterioration rates, repletion tends to occur on a cycle of once every four years on both the sanctuary and harvested grounds (Santopietro and Wesson 2015). The state now also charges a shell repletion fee of US$300 per licensed oyster harvester per year to help pay some of the costs for this shelling.
VMRC is now considering other potential responses to the increase in entry and overcapitalization that have followed the success and improved availability of market oysters from this rotational harvest strategy. Reducing the length of the season would negatively affect the shucking houses by disrupting the flow of product for processing, thus creating gaps in supply. Daily catch limits could be replaced by individual transferable quotas (ITQs) used in other fisheries around the world. The establishment of ITQs is usually based on records of historical catches. This is problematic because of rampant under-reporting of harvest to avoid taxation. A reduction in the number of watermen and the implementation of some type of limited entry to the fishery will most likely be implemented.
In 2007 the Commonwealth of Virginia commissioned a study to assess the economic value of the rotational harvest plan at the mouth of the Rappahannock. The researchers used a systems modeling approach to develop a bio-economic model of a harvest ground (Santopietro et al. 2009). Given the biological conditions known and economic conditions prevalent at the time, the model indicated that the oyster harvest would not be profitable for the watermen, nor would the state see an economic return on its investment in shell planting. Nonetheless, harvesters not only continued to work the grounds when open but invested in new harvest technology (i.e. scrapes) and devoted more effort overall to the fishery (PilotOnline 2011). New entrants were also attracted by high prices, abundant populations due to good spat sets, higher labor productivity and the decline in alternative fisheries.
The model was revised in 2015 to account for changes in the biological and economic conditions and the introduction of scrapes and to reflect management practices as implemented (Santopietro and Wesson 2015). Under some specifications, harvesters do have good years in which they can earn positive net revenues, even after accounting for the value of their time in alternative work such as construction labor. This would explain the evident overcapitalization and increase in effort observed in recent years.
Tension between oyster harvesters and state management authorities can be expected to continue as the price per bushel declines once production from the Gulf states increases and as the population of harvestable oysters falls due to smaller spat sets. Any continuing decline in other bay fisheries (e.g. blue crabs and striped bass) will also put more pressure on fishery managers as the watermen turn to alternatives like oysters on the public grounds. Environmental groups and members of the scientific community also have tense relations with the harvesters because they tend to favor growth of the oyster population for environmental benefits over harvesting. The watermen argue that because oysters die off in their third year, not allowing harvest simply wastes resources and does not thus generate non-market benefits. Conversely, the environmental interest groups, including federal agencies, point to the damage done to the oyster substrate and reefs by harvesting and recent evidence that the mortality rates may not be as high as in the past (Connor 2015). Pressure from harvesters, though, may decrease as younger entrants become more interested in aquaculture than harvesting public grounds, given recent advances in aquaculture technology and the ready availability of spat-on-shell and seed oysters from recently established oyster hatcheries.
The restoration of an oyster fishery at the mouth of the Rappahannock River following the drop in oyster populations throughout the Chesapeake Bay with the appearance of MSX and Dermo was made possible by the response of the governing system. The large-scale restoration program involved state-funded intensive shell replenishment to create a suitable substrate for oyster growth. Under pressure from harvesters to take the oysters that became available before they succumbed to disease and predation, the state responded by establishing a rotational ground opening scheme, which included limits on effort, including gear types, season length, daily limits and cull size, as well as the reservation of some areas as broodstocks where no taking is permitted. The adaptive capacity of the natural system nonetheless remains poor because of the continued presence of disease, sedimentation and other pollutants, predation, sudden fresh water flows from storms and the loss of the restored substrate over time. However, watermen and state management agencies have had success adapting to the existing natural system. In particular, private cultivation using improved genetics, cultivation and marketing techniques is producing new investment and growth in the oyster fishery, offering hope of reversing the long-term decline in this important coastal resource.
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