VICTORIA POND RESTORATION PROJECT GREAT EXUMA, THE BAHAMAS ECO-HYDROLOGY DEMONSTRATION PROJECT

July 5, 2017 | Autor: K. Sullivan-Sealey | Categoria: Coastal Management, Coastal Zone Management, Coastal and wetland restoration
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CASE STUDY SUMMARY – JUNE 2015 KATHLEEN SULLIVAN SEALEY, Ph.D. , JACOB PATUS, and YISHEN LI. Coastal Ecology Laboratory, University of Miami, Coral Gables, Florida, USA JOHN E. BOWLEG, P.E. C.Eng., C.Env, C.Sci (Hydrology).National Wetland Committee and Water and Sewage Corporation, Nassau, The Bahamas

PROJECT MISSION STATEMENT Since 2009, University of Miami ecologists, Exuma Foundation staff, and Exuma residents have worked to clean Lake Victoria, and restore the natural wetland environment in the center of historic George Town. Lake Victoria (aka “the Pond”) has suffered from a lack of coordinated management and poor coastal development practices; Victoria Pond was polluted and had been altered by roads, filling of wetlands and development for over 200 years. The Victoria Pond restoration project aims to eliminate the very real public health threat of rats, mosquitoes, and leaching of raw sewage into protected wetlands and waterways, and provides an opportunity to inspire residents. Victoria Pond was the largest and deepest of a series of connected mangrove lakes that provided a critical habitat for wildlife like tarpon, bonefish, herons, egrets, and osprey, and that provided controlled flooding along the eastern ridges of Great Exuma. The overall vision for the Victoria Pond restoration project is to demonstrate that a highly-altered coastal wetland can be restored and can regain ecological function. The project is designed to show the value of a protected wetland and coastal environment within a populated settlement; demonstrating that people can live alongside mangroves and their associated wildlife. The goals are: 1. To establish a local mangrove preserve that includes the Pond, an appropriate coastal buffer zone, channels, and associated embayment and ponds that will function as an ecological unit. 2. To complete the necessary clean-up, excavation, and restoration needed to restore natural drainage and tidal flow through the wetland preserve system; ultimately, the cleanup of Victoria Pond will improve the coastal water quality of Elizabeth Harbour. 3. To delineate the preserve area with markers and signage and restore native plant communities to the coastal zone of Victoria Pond. 4. To develop long-term community outreach and coastal stewardship programs to help maintain and finance the management of the Victoria Pond mangrove preserve. 5. To document measurable improvements in coastal water quality and near-shore fish habitat in the George Town environs over the ten-year project.

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1 ECO-HYDROLOGY OF GREAT EXUMA, THE BAHAMAS Great Exuma is the largest island in the Exuma island chain, with just fewer than 8,000 people (1) living on the island in six major settlements. George Town is the largest and oldest settlement, located at the southwestern shore of Elizabeth Harbour. The Harbour is a sheltered lagoon between Great Exuma Island and Stocking Island (Figure 1, right). Elizabeth Harbour represents one of the few natural harbours in the Bahamas and is the most popular yachting harbour in the country as the southernmost natural anchorage in the Bahamas. Over the past 20 years, a spatial database has been developed by the Coastal Ecology Laboratory at the University of Miami to understand the complex coastal processes that maintain the spectacular beauty of Great Exuma. The hydrology of the island is complex, with no surface fresh water resources. The climate is hot and dry, with larger inter-annual variations in rainfall.

Figure 1: Illustration of the berm and swale topography of Great Exuma. The southern Bahamas is hot and dry, with no surface water resources. The hydrology of Great Exuma is dominated by fresh water lenses, and ephemeral wetlands that form with high rainfall. Nutrients moving from land to sea naturally stimulate coastal production that supports tropical marine communities, including coral reefs.

The Central Bahamas includes the eastern half of the Great Bahama Bank, and is comprised of about forty main islands and many smaller islets and rocks extending along the platform margin of the bank. The Bank is surrounded by the western Atlantic, and includes a submarine canyon, Exuma Sound, to the east. Most of the bank area is very shallow (mean depth of 3 m), the bank margin includes the islands of Great Exuma. Near-surface flow in Exuma Sound can be characterized as primarily wind-driven (2). There are, however, meso-scale eddy fields superimposed on the northwestward drift (3) and dominant large-scale gyres extending to depths of 200 m (4). Except near tidal inlets, tidal oscillations are a minor perturbation to the wind-driven circulation. The platform 2|Page

shelf along the islands bordering Exuma Sound is narrow (generally < 2 km wide). Water exchange between Exuma Sound and the Great Bahama Bank occurs through numerous tidal inlets (ranging from < 100 m to > 2 km wide), which separate the islands. The eco-hydrology of Exuma has been investigated by compiling a spatial database (ESRI AcrMap 10.2) of the natural communities using the CMECS framework (5). This is a standard natural community classification scheme that uses not only geomorphological characteristics but energy, trophic and spatial qualities as well. The classification is applicable on spatial scales from less than one square meter to thousands of square kilometers and is applied at littoral, benthic and pelagic zones of estuaries, coasts and the open ocean. The classification standard is organized into a branching hierarchy of six nested levels. The levels correspond to both a functional ecological flow and a progressive map scale from the order of 1:1,000,000 (Regime) to the order of 1:1 (Habitat/Biotope). The oceanography and geomorphology of Great Exuma create three large marine ecological regimes (Figure 2):  Estuarine regime (green) that is restricted to the western margin of the island with unconsolidated sediment, and low relief, where ground water seepage enters small fresh water marshes, brackish wetlands and mangrove forests;  Marine Bank-side regime (orange) that includes the southern bank-side of the island dominated by shallow, soft sediment environments; and  Marine Ocean-side regime (purple) that includes the very diverse, ocean side of the island with coral reefs, hard bottom and soft bottom communities. The map below illustrates the ecological regimes and their associated coverages on Great Exuma. The completed CMECS maps are critical to the application of nitrogen loading models to determine most critical locations for advanced waste water treatment as well as long-term environmental monitoring of the island environments to document changes associated with increased landbased sources of pollution. Figure 2: Marine Ecological Regimes for Great Exuma. Location of freshwater lenses is dependent of the geology of carbonate rock layers and rainfall. Insert shows the detail for George Town/ Victoria Pond.

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The most important coastal resource for Great Exuma is the large natural harbour (Figure 3). Elizabeth Harbour is a large tropical marine lagoon located between Stocking Island and Great Exuma. The Harbour itself is 11 kilometers (7 miles) long and up to 3 kilometers (2 miles) wide with many embayments and cays. The Harbour is oriented from northwest to southeast, providing the largest natural anchorage for yachts in the country. The lagoon offers a protected anchorage along the shore of Stocking Island and other large cays (e.g. Crab Cay) for visiting yachts. Most of the lagoon is shallow, with depths rarely exceeding 4 meters (15 feet). The carbonate geology of the lagoon is typical of the Bahama Banks, with the active accumulation of sediments along sandy (unconsolidated) shorelines. The other critical feature of Elizabeth Harbour is the Moriah Harbour Cay National Park. The spectacular diversity of natural communities in the coastal and marine environments is represented by seven coral reef types, seagrass communities, and numerous coastal wetlands (Figure 3). The southeastern end of Elizabeth Harbour is dominated by mangrove wetlands along the shores of both Great Exuma, and the cays. There are few surface water resources on Great Exuma; storm run-off is the only surface freshwater input to the lagoon. Thus, Elizabeth Harbour is a true marine lagoon, not an estuary, with constant, relatively high salinities. The carbonate islands and cays around the lagoon have freshwater lenses that likely have seepage points for freshwater from the lenses to enter the lagoon along the shoreline. However, the movement of groundwater, including circulation through blue holes and subterranean caverns, is poorly documented. Elizabeth Harbour has not always been used exclusively for tourism; from the 1940's through the 1980's, the Harbour was home to the United States Navy. During World War II, the U.S. Navy dredged several large areas to the north and south of George Town to create deep-water access and seaplane landing sites. After the war, the Atlantic Undersea Testing Center (AUTEC) dredged and maintained navigation channels in the Harbour to support operations in Exuma Sound. The coastline in George Town has been bulk-headed and altered as properties expanded. Recently there is pressure to fill Kidd Cove to create more waterfront property. Initial studies of the ecology of George Town and Elizabeth Harbour were initiated by the Exuma Tourism and Environment Advisory Committee (TEAC) in 1995. The local office of the Ministry of Tourism was interested in documenting symptoms of degradation for the coastal environment, and identifying threats from human use of the Harbour environs. The residents and tourists disagreed on the causes of environmental degradation. In 2000, more frequent local fish kills and harmful algal blooms were thought to be the result of pollution. However, there were vigorous debates on whether pollution from the coast (Bahamians) or from anchorages (visiting yachts) was contributing to the environmental decline. Elizabeth Harbour was chosen in 2010 to participate in the Integrating Watershed and Coastal Area Management (IWCAM) in Small Island Developing States (SIDS) project. The IWCAM project is providing funding to address one of the issues causing degraded coastal water quality in Exuma, a major threat to the area’s seagrass and coral reef ecosystems. The Elizabeth Harbour Conservation Partnership (EHCP) was conceived during the Exuma IWCAM Project by a the Elizabeth Harbour Management Steering Committee composed of relevant national and local government agencies and local stakeholders as a strategy for managing tourism and natural resources in Elizabeth Harbour. The EHCP has recently received status as a Bahamian non-profit company. In 2011, the Victoria Pond Restoration Site was chosen as a UNESCO Eco-hydrology Demonstration Site to study best practices of restoration and management of coastal wetlands.

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Figure 3: Elizabeth Harbour shown with the classification of marine and coastal natural communities (CMECS 2012). The core area along with the expanded boundaries of the Moriah Harbour National Park dominates the southeastern end of the Harbour. George Town (including Victoria Pond study site ) is shown in the yellow circle.

Moriah Harbour National Park includes several uninhabited islands, and serves as an important reference site for comparing near shore water quality and marine diversity. The National Park faces threat from invasive coastal plants and over-fishing, but does not experience the land-based sources of pollution found around the Victoria Pond study site. The Elizabeth Harbour Conservation Partnership has taken responsibility for some resource stewardship like snorkeling site buoys within the Park.

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2. History of Coastal Alterations for the Victoria Pond Study Site George Town, Exuma, is among the islands’ most picturesque settlements, and fronts one of the most splendid natural harbours in The Bahamas. Today it has fewer than 500 permanent inhabitants. It was founded as the administrative center for British loyalists who first settled Exuma with their slaves after the American War of Independence, and might have become a potent naval base and commercial hub if not for the era of international peace following 1815 and the complete failure of Bahamian cotton plantations. George Town still has a handful of historic structures that were built in the early nineteenth century, including a church and parsonage, a courthouse/jail, a government dock, and a slave house that has been converted into a hotel called the Peace and Plenty. These buildings are all located on the small ridge and peninsula between Elizabeth Harbour and Victoria Pond. After slavery ended, a steady trickle of former plantation slaves migrated to George Town, settling mainly around the Baptist church on the south side of the mangrove lake. Victoria Pond was a center for ship careening and repair and even some shipbuilding in the early 20 th century. The township had minor surges of activity when small US bases were established during World War II, and again for anti-drug surveillance in the 1980s. But despite the six-fold increase in the Bahamian population and the 20-fold increase in the size of Nassau, George Town’s population had not grown since 1906 until 1994. In the 2010 census, Exuma was the fastest growing island in The Bahamas with the development of a destination resort at Emerald Bay, and several large residential resort communities. Residents voiced a very high level of problem recognition that tourism overall is contributing to a perceived degradation of the George Town and Elizabeth Harbour environs (6). One issue was the decline in fishing and fisheries resources. There have been no viable commercial fisheries in Exuma since the late 1980’s, and it is increasingly difficult for residents of Exuma to fish for local consumption. Residents feel that the increase in yachts, marinas and coastal development has had a negative impact on marine resources. George Town residents complained of the “foul smell” of Victoria Pond, small fish kills, and lack of large fish such as tarpon in the ponds. Residents are also of the opinion that the lack of holding tanks on visiting yachts and power boats has contributed to a significant pollution problem in Elizabeth Harbour. As many as 1000 boats can be in the Harbour during the winter months, with limited circulation in the shallow lagoon. Oceanographers have stated, “The solution to pollution is dilution”, and the high input of land-based and yacht pollutants exceed the natural flushing ability of the Harbour. Thus, pollution and contaminants are not flushed from the enclosed waters of the Pond or from the water front of George Town, and this is exacerbated by more filling and altering of the shoreline.

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George Town has been continuously occupied since the Loyalist period (over 250 years), with over 1000 years of human uses of the island from Tianos Amerindians harvesting turtles, sea birds and monk seals to Spaniards harvested hard woods for ship repair (7,8). It is important to keep in mind that those events from both past and the present influence the ecology and water quality of Great Exuma. The changes in the coastal environment of George Town have been subtle over time (Figure 5). Over 14 hectares of wetland has been filled and converted to land as the settlement expanded. However, there is a recent trend of land converting to water (2 hectares) that reflects sea level rise over the past 200 years. The ICPP 2014 report clearly warns of a period of rapid sea level rise, and regional planning considers a 2 foot (0.6 meter) increase in mean sea level rise by 2040 (25 years) a conservative guideline. Rising sea level and storm surge event present a serious threat to managing the coasts for Great Exuma. Figure 5: Historical changes in the coastal environment of Victoria Pond based on georeference historical maps and aerial photographs. Filled wetland areas around Victoria Pond are now areas of high flood risk.

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The initial clean-up of Victoria Pond was initiated with Earthwatch volunteers were on Great Exuma from 2009 to 2011. Expeditions were focused on island coastal ecology, and teams participated in the restoration work. Bahamian interns from the Young Marine Explorers worked to organize the restoration tasks that included:  Trash removal, planting native plants, planting mangroves, and designing the outreach signs.  Water quality monitoring at 15 stations around the Victoria Pond and Elizabeth Harbour;  Fish, marine plants and coral monitoring of 7 stations around Victoria Pond and Elizabeth Harbour;  Coastal surveys throughout Great and Little Exuma to complete the island wide maps on the state of the coasts, and  Start of restoration at the Steventon Landfill, including planting of native trees on Cell #1. The canal behind Lovers’ Lane (aka Ugly Corner) continues to have poor water quality and trash accumulating. Although more water is moving through this area, turbidity is high, and dissolved oxygen continues to be low (Hypoxic conditions). This area requires the most intensive work for restoration, and the Ecohydology project team contributed by establishing the coastal buffer zone areas, and continuing to record water quality parameters. Although there were trash containers and a nearby recycling bin, trash continued to be thrown in the wetland areas. Solid waste is likely the biggest threat to wetlands throughout Exuma, and one of the problems that can be addressed through more outreach and recycling efforts. Solid waste management should include recycling or reuse of material for both cost savings, environmental protection, and revenue enhancements. Unfortunately for SIDS, the long-term environmental costs of dumps and landfills are seldom considered.

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Restoration volunteers planted red and white mangrove seedlings at low tide from 2010 through 2012. Mangroves planted in January 2010 have had about an 80% survival rate, and continue to thrive in the restoration areas. Mangroves planted along Lovers’ Lane all died from poor water quality and this area remains a special concern. The Exuma Foundation continued to support the Victoria Pond Restoration Project with the use of the shade house for native plant propagation. Volunteers harvested cuttings and seeds from native plants on Exuma to propagate for restoration projects. Species successfully propagated include: Native inkberry Sea Purslane (Sea Pickle) Sea Lavender Bay Cedar Sea Ox-Eye Black Torch Sea Oats Sea Cordgrass (Spartina patens) Cocoplum Strong back Sea Grape White mangrove Red mangrove The identification and protection of native plant species is part of the larger effort to promote environmental stewardship for Exuma. The larger problem is organizing the long-term care and maintenance of wetland protected areas on Exuma. Wetlands protection and management is not part of any Ministry portfolio outside of the designated national parks.

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Table 1: Symptoms of degradation or change in the Victoria Pond/ George Town environment: Some changes can be part of natural variation in ecological processes over time; some changes can be attributed to human impacts on the Harbour system. The assessment was designed to investigate these symptoms and report on the condition of marine resources in the Harbour relating to water quality issues.

SYMPTOMS Change in water color, Decrease in water clarity; Change in water to murky color and greenish in appearance

DESCRIPTION AND REPORTED EXTENT    

Foul smell to water, especially in summer

  

Decrease in amount of live coral and “color” on patch reefs in the Harbour

    

Decrease in the fish seen or caught in the area

   

Decrease in the number of adult snappers on reefs within the Harbour



Water is turbid, and no longer clear Fish kills seen in summer morning hypoxia events Less water clarity in areas adjacent to George Town, off Regatta Point, Kidd Cove and Victoria Lake. More jelly fish in the water near the boat ramp Victoria Lake and Kidd Cove area have “sewage” or rotting smell, especially in summer, Shoreline of Kidd Cove covered with filamentous green algae Sewage smell along water at “Ugly Corner” Decrease in the reefs both at the southeastern end of the Harbour and patch reefs near Stocking Island anchorage Reefs appear dead or covered with algae Increase in fire coral More fishing line caught on the reefs Loss of coral patches in areas adjacent to dredged channels and docks. No more tarpon seen in Victoria Pond No lobsters seen inside of Elizabeth Harbour Residents must use a boat, and travel further to fish for food Fewer residents eat fish on a weekly basis Recreational fishing pressure undocumented for Harbour area, but reports of poor fishing compared to 30+ years ago, fewer large fish seen in Harbour, fewer fish in or adjacent to shoreline in George Town

Photos of Victoria Pond in 2009 prior to the start of the clean-up project. Many of the mangroves around the pond had been removed, and illegal dumping occurred in the remaining mangrove areas

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2 ECOLOGICAL IMPACTS AND IMPLICATIONS FOR COASTAL WETLAND LOSS AND ALTERATIONS AROUND VICTORIA POND STUDY SITE For general discussions of global ecosystems, the Bahamian archipelago would be considered an Oligotrophic Ecosystem, with less than 100 grams of carbon fixed per meter squared per year. This accounts for the clear turquoise waters that are characteristic of the island system. The ecology of the islands with very low nutrient input from land-based sources means that eutrophication can occur in Bahamian waters as the result of very small coastal nutrient fluxes (9). Many of the shallow, near shore environments are at risk from land-based effluence and coastal development (10, 11).

FOOD AND ORGANIC WASTE

DIETBASED NITROGEN OUTPUT (SEWAGE)

Our Nitrogen footprint can well be the defining parameter for sustainability. Nitrogen is considered the most important pollutant to TOTAL marine and aquatic systems globally. The NITROGEN shallow natures of carbonate back reef INPUT TO systems enable their high productivity, ECOSYSTEMS

but incur the cost of high sensitivity to intense variability in physical and chemical environmental parameters (12).

Near shore habitats will be the first to experience any negative impacts stemming from onshore development. Marine organisms that live close to shorelines naturally face high sea surface temperatures of extremely shallow waters, periodic high turbidity periods, caused by heavy rainfall or storm events, and potential of elevated nutrient efflux from land-use changes Acute eutrophication can occur over a relatively short time period and induce changes over smaller spatial scales, while chronic eutrophication poses a threat of gradual changes that influence broader spatial scales. Controlling eutrophication and coastal hypoxia is critical to sustainable development and coastal management; however, there are many poorly-understood processes that control the fate of nutrients once they enter the porous carbonate islands of The Bahamas. General symptoms of coastal eutrophication can be described by but are not limited to physical and biotic parameters (Table 1). What are the minimum water quality parameters and frequency of measurements needed to determine risks of eutrophication? The term “water quality” is used to describe the collection of physical and chemical characteristics of water that support the functioning of near shore flora and fauna. Water quality per se does not mean crystal clear, potable water, but rather the unique combination of physical and chemical parameters that support ecological communities. Temperature is critical because it can influence dissolved oxygen levels, the rate at which algae and aquatic plants photosynthesize, the metabolic rates of aquatic organisms, how aquatic organisms are affected by 11 | P a g e

different pollutants, parasites and pathogens, the solubility of solutes (e.g. calcium carbonate), and it determines the density of seawater. Salinity is the total gram weight of dissolved substances (salts) in one kg of seawater and on average seawater has a salinity of 35 parts per thousand (ppt). Daily alterations in factors including weather, tidal cycles, and seasons can cause salinity levels to fluctuate (11). Most aquatic organisms function optimally within a narrow range of salinity and when salinity changes to above or below this range, an organism may lose the ability to osmo-regulate and thus become susceptible to biotic pressures such as predation, competition, disease or parasitism. Thus, changing salinity levels can affect the distributions of marine plants and sessile organisms (12, 13). In the Bahamas salinity levels can also be influenced by the amount of groundwater seeping into near shore waters and by large incursions of storm-water runoff. The principal gases dissolved in seawater are oxygen and nitrogen. Nitrogen is conservative and changes by mixing only; whereas oxygen is not conservative because it’s biologically active. The amount of dissolved oxygen (DO) in water controls the distribution of organisms. Seawater is generally between 1 and 9 milligrams per liter (mg/l) depending on temperature and depth (14); below 2 mg/ l is considered hypoxic and stressful to marine life. In warm Bahamian waters, oxygen levels below 60% saturation are stressful to tropical marine animals such as fish and corals. Sedimentation rates, from storm water run-off, are also linked to water quality. Turbid waters after a storm decreases the light reaching the sea floor and the animals living there. Patterns of increased turbidity from storms are linked to coastal eutrophication. A major source of the small hypoxia events in near shore areas is linked to coastal alterations that change hydrological cycles, particularly ground water discharge. These alterations include residential canals, filled wetlands, and causeways. Coastal alterations can also disrupt near shore circulation and flushing, allowing nutrients to accumulate in enclosed ponds, bays and lagoons. The “Eutrophication index” (Figure 6) was developed to identify areas of poor water quality and evaluated marine plant species assemblages in the Victoria Pond/ George Town study area. Hypoxic conditions occur when dissolved oxygen drops below 60% saturation (for the temperature/ salinity conditions) and turbidity is over 10 NTUs. Turbidity due to re-suspended sediments high in organic content often trigger harmful algal blooms in the water column, and thus, increased sedimentation rates are associated with eutrophication. Poor water quality in coastal wetlands is also associated with a number of public health risks, especially in areas with sewage exposure and seepage. From 1998 to 2009, Victoria Pond lost 60% of the fish species found in the pond, and about 38% of the seagrass habitat was lost. The declining water quality resulted in a loss of diversity of marine life within Victoria Pond and the adjacent Chen Pond wetlands. People no longer fished or swam in the pond, and around the perimeters of the wetlands, trash was dumped to fill wetlands. The loss of ecosystem services in the coastal wetland complex increased the vulnerability of the area to flooding and harmful algal blooms associated with storm events. With a less desirable environment, property values around George Town dropped as the settlement became a less desirable place to live. 12 | P a g e

Hypoxic Conditions Figure 6: A summary of water quality for Victoria Pond from 2004 to 2010 illustrating the increased eutrophication and hypoxic events occurring in Victoria Pond and the adjacent Kidd Cove off George Town.

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3 RESTORATION ACTIONS AND PLANNING FOR A RESILIENT COASTAL ENVIRONMENT Five years after the initiation of the Victoria Pond Clean-up and Restoration Project, the coastal wetlands show some signs of improvements. Monitoring of water quality and marine fauna shows continuing degradation around George Town after major storms and rain events. New project emphasis is now being placed on using wetlands as tools to mitigate flood risk and to protect near shore water quality. The wetland restoration has launched an island-wide assessment of wetlands and coastal resources for better coastal zone management, especially looking at wetland resilience in disaster and flooding events. The threats that have been targeted in the restoration planning for Victoria Pond include: 1. Physical Damage to coastal environments: Poor management of the coastal zone results in loss of ecosystem services (14), particularly loss of stability and resilience to storms, loss of wildlife habitat along with increased vulnerability of coastal property; 2. Eutrophication from pollutants, including sewage, discharged directly from sailboats and indirectly from seepage from “soak-aways”: Sewage and storm water runoff from any development includes excess organic material, pollutants and nutrients. Nutrients from sewage and land run-off are the source of the over-stimulation of algal growth and results in the algal overgrowth on coral reefs as well as the decline of seagrasses, and 3. Over-harvesting of essential marine species: Healthy reefs need spiny lobsters, snappers, grunts and groupers – the full complement of species in the natural community to help protect the natural community from change. Fishes and lobsters have been overfished, and critical nursery areas degraded; and 4. Filling of wetland areas with solid waste dumping: dumping in wetlands reduces the ability of wetlands to absorb rain and reduce flooding. The water shed around the Pond was mapped for building location, size of the buildings, along with number of occupants to determine the overall nitrogen loading. Annual Nitrogen loading is estimated to 5736 kilograms of nitrogen per year. This amount outstrips the ability of the compromised wetland to process. Although a local committee does organize trash clean-ups, there is little understanding of how people and the mangroves should co-exist, or how mangroves can protect shorelines, provide wildlife habitat, and process pollutants. The restoration methods developed and reviewed by the local community include improving flow through the Pond, and increasing the aesthetics of the Pond environs through four restoration tasks. Each of the restoration tasks requires a construction component and a community or volunteer component, such as replanting, and a stewardship. Throughout the project, government agencies, residents, businesses and visitor all played a role in clean-up, replanting, providing services (such as heavy equipment and trash containers).

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Figure 6: Spatial assessment of land-based sources of pollution based on individual human nitrogen footprints. Each person on Exuma consumes about 88 grams of protein per day (based on WHO diet assessment and volume of grocery commodities imported to Exuma courtesy of Yishen Li) The Victoria Pond Restoration project was initiated in June 2009 with a Community Clean-up. Over a period of one year, detailed restoration plans were developed for public review and implementation, based on four major tasks (Figures 7 and 8). The four major construction tasks were identified as: - Task #1: FEBRUARY POINT CAUSEWAY: Excavation and installation of culvert pipes in causeway bisecting the pond east of Victoria Pond at February Point. - Task #2: EAST CANAL (aka “Ugly Corner”) RESTORATION OF MANGROVE CREEK: Debris Removal and Sediment Removal of Open Culvert and Drainage Canal connecting Victoria Pond with Back Pond, east of Queen’s Highway Loop in George Town, Great Exuma Island. - Task #3: VICTORIA POND WEST CANAL CREEK RESTORATION AND BRIDGE CONSTRUCTION Debris Removal and Sediment Removal of Box Culvert connecting Victoria Pond with Back Pond, west of Queen’s Highway Loop in George Town, Great Exuma. - Task #4: QUEENS HIGHWAY BOX CULVERT CLEARING Debris Removal and Repair of Box Culvert Connecting Victoria Pond with Back Pond, Culvert Located beneath Queen’s Highway Loop in George Town.

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Fi g ur e 7: Lo ca to r M a p fo r th e Vi ct or ia P o n d R es to ra ti on Project. The Initial restoration (2009, purple) involved removing illegal dumping of trash and construction waste to improve circulation between Victoria and Chen Ponds. Mangroves were planted along rock revetments. The second task was the installation of culverts in the causeway added to Chen Pond (2011, green). Most recently, the box culvert has been replaced (2015, orange).

The Victoria Pond restoration project has been initiated to restore the function of mangrove wetlands to a) Improve near shore water quality, and b) Enhance coastal fish habitat, particularly for fish and spiny lobster. Both of these objectives serve the economic and ecological needs of Great Exuma. The management of the coastal zone can be a critical mechanism to protect not only biological diversity of species and natural communities, but also ecological function of coastal environs (e.g. in seagrass meadows, (16)). Coastal buffer zones under the stewardship of local communities can protect mangrove systems, provide green space, and limit the extent of coastal alterations, thus protecting near shore ecology. These coastal services are even more critical in a period of rapid sea level rise. Over the past decade, local governments in George Town managed Victoria Pond in an ad-hoc manner, responding to short-term goals of restoring a “view of the water” from the roadway, or rapidly drain areas that periodically flood, with no resources or technical assistance. Human communities require more tangible results to support environmental management initiatives. Residents of George Town agree the Pond smells bad, and is not attractive (refer to Table 1); local government must respond with some action, although that action is not 16 | P a g e

vetted for environmental regulatory compliance

Figure 8: Overview Diagram of the Victoria Pond Restoration Project. Tasks are detailed with additional photos and engineering diagrams approved by local government in May 2011.

The coastal zone of small islands is critical to ecological function of island systems. The Victoria Pond restoration project aims to better understand and demonstrate the ecosystem function provided by coastal buffer zones, especially indicated by more abundant and diverse fish assemblages. There have been some miscommunications about the coastal buffer zones; these are the first areas impacted by tourism and infrastructure development on islands. The Bahamas is set apart from other Caribbean countries by the lack of an Integrated Coastal Zone Management and Planning Unit (ICZM). The Coastal buffer zone is the functional use (and design) of coastal setbacks to: a) Stabilize the coast, and protect property from storm surges and erosion, b) Allow the coastal buffer of natural vegetation to filter groundwater and storm run-off to prevent pollutants from entering the near shore marine environments, and c) Protect the native plant diversity on the island by allowing contiguous zones of native vegetation, with natural topological gradients in the coastal dune and swale systems. 17 | P a g e

Recent legislation (2009) for sea turtle protection does make reference to protection of dunes and a beach system used for turtle nesting, but does not address the coastal restoration and establishing of coastal setbacks. Although buffer zones and setbacks are specifically mentioned in the National Wetland Policy (15), there are few guidelines for implementation or remediating historical or existing encroachments on fully-protected wetlands. Funding will need to come from both public and private sources over many years to complete the physical restoration and sustain with wetland stewardship activities. Only over time will the economic benefits be apparent, and the rewards of coastal zone management realized. The Bahamas has existing laws, policies and treaty commitments that present expectations for coastal zone and wetland management, but lack incentives for immediate action. The National Wetland Policy’s stated purpose is to provide one document that outlines the Government of The Bahamas’ position on wetland protection. The policy applies across departments and agencies with any management or regulatory responsibility for land-use planning, coastal and marina development, placement of septic systems or protection of marine resources. Only through on-the-ground demonstration projects like the efforts at Victoria Pond will the value of these national policies be appreciated by local communities. Since 2011, the Victoria Pond-Chen Pond wetlands have been monitored twice a year to determine the level of eutrophication to wetlands and near shore marine environments from land-based sources of pollution. However, on the Bahamian islands, nutrients and sediment also enter near shore waters through ground water seepage and surface storm run-off, and this nearly-ubiquitous exchange of freshwater and nutrients off small carbonate islands makes the coastal zone especially sensitive to eutrophication with human disturbances. All coastal environments improve with restoration, and Victoria Pond is no exception. Table 2 illustrates the increase in the diversity of marine life over time with the installation of culverts in the causeway across Chen Pond (adjacent to February Point resort). Further improvement in the ecology should be seen with the improvement in the flow of water under the Queen’s Highway through George Town. A larger challenge that remains is the proximity of cesspits along Ugly Corner. Table 2: Summary of major ecological parameters measured over time (2009 to 2014) to assess the impact of coastal restoration on Chen Pond and Victoria Pond marine environments. (Sealey et al, in preparation) Parameter Number of fish species recorded in 20 hours of surveys Number of marine plants recorded / 2,500 sq meter Number of benthic invertebrates / 2500 sq meters Dissolved Oxygen percent saturation (Sunrise) mean for year (at culverts)

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2009

2011

(mangroves planted)

(culverts installed )

4

2012

2013

2014

6

9

14

22

15

12

18

23

31

7

7

7

11

16

42%

38%

47%

52%

64%

The increase in circulation from culvert installation has improved the ecology of Chen Pond, but the changes are slow. Restoration efforts have not addressed the source of nutrients and pollutants into the wetland system from the George Town environs. Further assessment on the recovery of seagrass beds in Victoria Pond and Chen Pond are underway. Exuma water quality stations in Elizabeth Harbour have also been monitored since 2011 with no detectable improvements noted in terms of either increases in oxygen or decreases in turbidity. The goals of the Victoria Pond monitoring program are to look for and prevent long-term chronic changes to coastal systems. Thus, water quality analysis was coupled with baseline data on fish, invertebrates, macro-algae and ranking of coastal alteration. As this project is dependent on community participation and funding, new actions in restoration are pending. A new strategy was employed in 2012 after severe flooding occurred in George Town – the project team focused on creating a wetland and elevation map of the entire island of Great Exuma to evaluate flood risk to property, (Figure 9) and identify priority locations for wetland restoration to mitigate flooding risks. The resulting maps can be used to evaluate the vulnerability of human settlements to both inundation (extreme rainfall) flooding or storm surge.

Figure 9: Map illustrating the coastal elevation and vulnerability to flooding and sea level rise.

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5. LITERATURE CITED (1) Government of The Bahamas, Department of Statistics. 2011. Preliminary Report on the 2010 Census, Commonwealth of The Bahamas. Department of Statistics, Nassau, Bahamas. 8pp. (2) Stoner, A. W., & Lally, J. (1994). High-density aggregation in queen conch Strombus gigas: Formation, patterns, and ecological significance. Marine Ecology Progress Series, 106(1-2), 73-84. (3) Colin, P. (1995). Surface currents in Exuma Sound, Bahamas and adjacent areas with reference to potential larval transport. Bulletin of Marine Science, 56, 48-57 (4) Lipcius, R. N., Stockhausen, W. T., Marshall, L. S., Jr., Hickey, B. M., & Eggleston, D. B. (1995). Metapopulation dynamics of the Caribbean spiny lobster. 23rd Benthic Ecology Meeting, New Brunswick, NJ (USA), 17-19 Mar 1995. Grassle,-J.P.; Kelsey,-A.; Oates,-E.; Snelgrove,-P.V. (eds.) Rutgers-the-State-Univ., New-Brunswick, NJ, USA. Inst. Marine Coastal Sciences. (5) CMECS. 2012. Coastal and Marine Ecological Classification Standard Marine and Coastal Spatial Data Subcommittee. Federal Geographic Data Committee FGDC-STD-018-2012. Washington, D.C. USA. June, 2012. 353 pp. (6) Government of The Bahamas, Ministry of Tourism. 1999. Exuma Eco-Tourism Planning Workshop. George Town, Exuma 27 – 29 January 1999. Workbook developed by James MacGregor, Ecoplan, Ltd. Canada. (7) Keegan, W. F. 1997. Bahamian Archaeology: Life in the Bahamas and Turks and Caicos before Columbus. Media Publishing, Nassau, Bahamas. 187 pp. (8) Albury, Paul. Story of The Bahamas. St Martins Pr (March 1976) (9) Sealey, K. 2004. Large-scale ecological impacts of development on tropical islands systems: Comparison of developed and undeveloped islands in the Central Bahamas. Bulletin of Marne Science. (10) Nero, V.L. and K.M. Sullivan Sealey (2007). Island Specific Responses of Bahamian Benthic Flora t o Environmental Features. Caribbean Journal of Science. Also, Nero, V.L. and K Sullivan Sealey. 2006. Fish-environment associations in coastal waters of Andros Island, The Bahamas. Environmental Biology of Fishes 7, 223-236. (11) Sullivan Sealey, K., V N. McDonough, K. Semon Lunz. (2014) Coastal impact ranking of small islands for conservation, restoration and tourism development. Journal of Ocean and Coastal Management. Volume 91, April 2014, Pages 88–101. (12) Barbier, E. B., Hacker, S. D., Kennedy, C., Koch, E. W., Stier, A. C., & Silliman, B. R. (2011). The value of estuarine and coastal ecosystem services. Ecological Monographs, 81(2), 169-193. Also, Nagelkerken, I. (2009). Ecological connectivity among tropical coastal ecosystems. New York: Springer Verlag. (13) McGlathery, K. J., Sundback, K., Anderson, I. C. 2007 Eutrophication in shallow coastal bays and lagoons: the role of plants in the coastal filter. MEPS, 348, 1-18. doi: 10.3354/meps07132 (14) Nixon, S.W. 1995. Coastal marine eutrophication: a definition, social causes and future concerns. Ophelia 41:199219. (15) Cambers, Gillian. 1998. Coping with Beach Erosion: Coastal Mangement Sourcebook 1. United Nations Educational, Scientific and Cultural Organization, CSI, Paris, France: 61pp. (16) Bahamas Environment Science and Technology (BEST) Commission . 2005. National Environmental Management Action Plan (NEMAP) for The Bahamas. Nassau, Bahamas. 89pp. Also, Bahamas Environment Science and Technology (BEST) Commission. 2002. Bahamas Environmental Handbook. Nassau, Bahamas. 64pp.

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