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Restoring British Virgin Islands Ecosystems and Fisheries
Thomas J. Goreau, PhD 1. GENERAL ENVIRONMENTAL STRATEGY ISSUES The British Virgin Islands has long been renowned for its excellent snorkeling, so healthy coral reefs have been the major natural resource base for BVI’s tourism and boating economy as well as its fisheries. The health of BVI’s coral reefs have not been the result of wise management, but a series of lucky accidents: low population, low pollution levels from sewage and industry, low deforestation and erosion rates, and its location in the very northeastern Caribbean, flushed by clean Atlantic ocean waters. Nevertheless, despite these advantages, BVI’s reefs have declined severely, even if not as badly as most of the rest of the Caribbean. In 1979 almost all the Elkhorn and staghorn corals, which made up the bulk of the shallow reefs, and were responsible for most of the fish habitat and shore protection, died from White Band Disease. While there has been more recovery of these crucial species than is seen elsewhere in the Caribbean, their amounts are still only a tiny fraction of what they were, and they are threatened by White Plague and White Pox diseases as well as recurrent White Band disease. Nutrients from inadequately treated sewage have caused algae blooms to overgrow and kill reefs near population centres. And a very large proportion of all of the corals (roughly a quarter to a half, depending on location) in BVI died in 2005 from extreme high regional temperatures caused by global warming. Given the accelerating and unavoidable stresses to the reefs caused by climate change and new diseases, the last thing BVI should do is increase stress to the remaining coral reefs by allowing increased sedimentation and nutrients from uncontrolled and ecologically unsustainable “development” schemes that are destroying the very natural beauty on which BVI’s economy is based. BVI’s national coral reef management strategy should be based on conserving all the good reef remaining, and actively restoring the degraded areas critical to fisheries, tourism, and protection from coastal erosion. At this time the Turks and Caicos Islands are the only country in the world to have a national strategy to address these issues (T. Goreau, 2006, Turrks and Caicos Islands: Coral reef assessment and restoration and management strategy). TCI is the only place that requires all developers to build secondary sewage treatment plants and then to recycle all the wastewater on their own properties without discharge, in order to avoid polluting the coastal zone, and is the only country to adopt water quality standards specifically designed to protect coral reefs. TCI is the only country that not only enforces their environmental laws, they do so to higher standards than the letter of the law requires. That is because having survived slavery and economic abandonment, the people lived off the sea for hundreds of years, and even though they now have tourism and financial services, they know that these are fragile, could collapse at any moment due to political factors beyond their control, and they could be forced to survive from the sea again. So they have taken every possible step to preserve their reefs and fisheries, to prevent outside investors from destroying or damaging their resources, and started promoting active marine habitat restoration. BVI should do the same, for their own long-term self-interest. Effective marine resource management requires not only effective laws, but also the will to enforce them, developing the means to identify locally caused factors that could stress reefs before they are out of control and strategies to reduce them. At the same time the British Government should be encouraged to act much more forcefully in international climate negotiations to reverse global climate change that is killing corals. 2. WATER QUALITY ISSUES Water quality problems in BVI are visible in the form of high levels of algae that smother and kill corals, and are largely located where there are land-based sources of nutrients (nitrogen and phosphorous) entering the coastal zone, largely from inadequately treated sewage. These nutrients are fertilizers, and just as throwing fertilizer on an empty field yields bumper crops of weeds, releasing them into the coastal zone causes massive growth of algae and bacteria that overgrow and kill corals, and wipe out reef habitat and fisheries. In BVI there are few industrial or agricultural pollutants, so sewage is likely to be the major problem, although some sites down-current from offshore sites where deep, cold, nutrient-rich water is brought up by winds, waves, and ocean circulation can be naturally, but episodically, enriched in nutrients. Coral reefs are the most sensitive of all ecosystems to nutrients, and are smothered with weeds at levels that would affect no other aquatic ecosystem. Therefore they require the strongest water quality standards and the most effective recycling of nutrients on land (T, Goreau, 2003, Waste Nutrients: Impacts on coastal coral reefs and fisheries and abatement via land recycling, UN Expert Meeting on Waste Management in Small Island Developing Countries). There is no systematic monitoring of nutrients in BVI, and therefore coastal managers do not know the amounts and sources of nutrients to the coastal zone, and are unable to devise strategies to reduce them, even though growing population and mega-developments are greatly increasing sewage effluent loading to the coastal zone. Because BVI is surrounded by clean open Atlantic Ocean water, algae in coral reefs are generally very low by Caribbean standards except next to human population concentrations, but these areas are highly vulnerable to only very small increases in nutrients from existing or new sources. The pattern of spreading algae that degrade reefs has been seen all over the Caribbean, not just in densely populated places like my own home island, Jamaica, but even in low lying, dry, sparsely populated islands such as the Turks and Caicos, Bahamas, Bonaire, and Cayman. While the bulk of these nutrient sources are from sewage, agricultural runoff can play a role locally, as do captive dolphin pens, turtle farms, and hatcheries. No coral reef country in the world has mapped nutrient distributions in their coastal waters, even though this is needed to identify the sources of nutrients triggering changes in reefs and fisheries, to devise specific policy actions to reduce them, and to test if such steps are effective. Without doing so, the database needed for effective scientifically-sound management does not exist. While most Caribbean countries have already lost most of their coastal reefs, in BVI the problem is still in the early stages and might still be dealt with, before the damage to the reefs is irreversible, by treating existing wastes better and preventing new sources. The issue of boat anchorages and waste discharges also needs to be seriously addressed. While the bottom at Trellis Bay seemed to be clean of weedy algae, indicating that the boats anchored there were not releasing wastes into the Bay, other anchorages need to be examined for signs of environmental impact. For example at boat anchorages in the Grenadines, which is along with BVI the major yachting center of the Caribbean, the bottom is covered with dense masses of algae indicative of sewage inputs, which are not found away from the anchorages. While much concern is raised about the damage to the corals by uncontrolled anchoring, the impacts of nutrients must also be considered. An additional factor needing much more attention is the sediment loading caused by erosion from land clearance and badly planned construction on hilly terrain, as well as poor drainage of inadequately designed roads up the steep hills. Sediment control has recently become a major focus of efforts to protect corals in the St. John Marine Park, which was established following my father’s environmental assessment around 50 years ago. BVI already possesses a critical element in setting up a national water quality assessment in the large collection of state of the art marine equipment that has been purchased for the H. Lavity Stoutt Community College, but which has never been set up. This is due to lack of personnel skilled in setting up and maintaining this equipment, and lack of a funded program that would use it. In some cases the equipment that was bought can only be used to analyze nutrients in samples that are collected in the field and brought back to the lab, but this causes numerous problems in interpretation because of sampling, storage, and analytical errors, and because the samples taken must be widely separated in space and time. It would have been far more useful to have gotten equipment that could be used for continuous real time measurements in the field from small boats, allowing nutrient maps to be prepared all around whole islands, identify every single nutrient source, and track each to its origin, while eliminating storage and sampling artifacts. But the personnel and long term monitoring environmental programs must be in place for this equipment to be effectively used. This is an issue that needs a comprehensive policy, strategy, and funding involving the College, the Government Department of Environment and Fisheries, and scientific researchers. Because much of this equipment would be primarily used for intensive field mapping at selected times of the year, it could be profitably used for regional programs in several places. This would fit with the original mandate of the Maritime Program to serve regional needs. An especially attractive route for funding from the British Government Overseas Development Assistance would be to create a regional program involving all the British Caribbean territories, which all face similar water quality problems and needs. The 2006 Turks and Caicos coral reef assessment, conducted by the author, reveals systematic patterns of excessive algae reflecting both human and natural nutrient sources, and calls for the development of precisely the same kind of nutrient mapping capability by the TCI Department of Environment and Coastal Resources. A similar but much briefer assessment of algae problems carried out by the author in 2005 for the Cayman Government Department of the Environment also revealed widespread algae problems related to nutrient sources from sewage, garbage dumps, golf courses, and in some cases, natural sources. Based on that study the Cayman DOE sought funds from the British Government to set up a “Regional Centre of Excellence in Water Quality Studies” and while it received some funds for this in 2006 follow through seems to have been stalled. The point is that the environmental agencies in both Turks and Caicos and Cayman have identified this lack of water quality monitoring capability as a serious obstacle to sound coastal zone management and have stated the desire to resolve it. BVI could collaborate with Turks and Caicos and Cayman, and in addition with Anguilla and Montserrat to develop tools that could be shared regionally and be more attractive for British, Canadian, or EU funding agencies. Such a program could logically use the H. Lavity Stoutt Community College Maritime Program facilities as a permanent laboratory base for the program, and add on instruments for field monitoring capabilities to be shared with other regional government environmental agencies. 3. NEED FOR A NATIONAL REEF RESTORATION STRATEGY The quality and quantity of coral reefs with good snorkeling and diving has steadily declined in BVI. Many coral reefs near hotels that once had excellent snorkeling right in front of their beaches now have dead or nearly dead reefs. Long-term divers are all aware of the constant deterioration of the reefs, but most are secretive about it, since the success of tourism means selling the image of pristine reefs in paradise, a place where by definition nothing can be wrong. Since all BVI’s competitors are selling the same lie, no one can admit that their reefs are on a downward death spiral, because to be honest about this would be a self-inflicted wound from a commercial standpoint. The general decline of reefs all around the world means that as BVI reefs decline, the decline in the reefs everywhere else are such that BVI’s reefs remain RELATIVELY better, even as they steadily become less and less. But it would be foolish to be complacent because they are deteriorating at a slower rate. In my view it is unwise for BVI to base its coral reef management strategy on self-deception for tourism public relations, because you can’t fool Mother Nature or what she will do to those who willingly or unwittingly squander their natural resources. An honest appraisal of the problems is critical to developing any will for active restoration. At this moment the Turks and Caicos Islands is the only country in the world with an official policy draft for a coral reef restoration policy, the rest are totally unaware of what is happening to their marine resources, in denial (Cayman hired Jean-Michel Cousteau to go to dive shows and say that “thanks to the hurricanes, Cayman reefs are now better than ever” when in fact they had been heavily damaged), in deliberate concealment (Bonaire is suppressing the long term photographic record showing continuous decline in coral cover because of fear that it would affect tourism). None of these responses will result in pro-active efforts to restore their damaged reefs which will decline even faster in the coming years as global warming, new diseases, and land-based sources of pollution accelerate greatly. BVI should encourage or even require all shore front properties to restore the coral reefs in front of them. This would not only provide a resource for ecotourism, it would at the same time provide shore protection and habitat to restore the fisheries. The best option for doing so is to use Biorock® technology which uses safe low voltage electrical currents to grow reef frameworks of any size or shape on which corals typically grow 3-5 times faster than normal, have 16-50 times greater survival from severe bleaching heat stroke, and which attracts dense populations of fish, especially juveniles. The Global Coral Reef Alliance, the developer of this technology, is ready to work with all serious partners to restore their reefs. While this technology is unique in restoring coral reefs in a few years in places where no natural restoration is taking place, protecting good natural reefs (and mangroves) must take first place because restored ecosystems are not a full substitute for old mature ones, and the possibility of restoration should not be used as an excuse to permit destruction. 4. PRESERVATION OF THE RHONE The wreck of the Rhone is the major dive attraction in BVI. The wreck is unusually well preserved because of a lucky accident that has not been pointed out before now. When the Rhone sank it contained several different metals and because each metal has different electrical potentials in seawater, this caused small electrical currents to flow through the water between them. Those metals that acted as anodes, such as zinc, magnesium, or aluminium, were dissolved away. While they lasted, the current halted rusting of the steel, and caused a thin layer of limestone rock to grow on top of the steel structure. This preserved the steel and created the substrate on which baby corals prefer to grow, and as a result of this electrochemical limestone veneer the wreck was heavily settled by reef building corals. In fact the density of coral settlement on this limestone surface is much higher than on the nearby rocks, making the Rhone an oasis of life. Shipwrecks that lack this protective action quickly rust, and few or no reef building corals settle on them, only sponges, stinging hydroids, and a few soft corals. However with the complete dissolution of the anodic metals, now the limestone coating is no longer growing, and the protective electrical currents that completely blocked rusting have now disappeared. Worse, now the steel acts as an anode with regard to the copper, brass, and bronze fittings, so now these are growing protective limestone while the rusting of the steel is accelerating. This can be seen as little rust spots beneath the overlying limestone and coral, and will get worse with time, Many ship wrecks undergo greatly accelerated rusting once they are discovered for diving, because of the oxygen from diver’s air bubbles and the enhanced circulation from bubbling and fin kicks. I suggest that the structure be electrically protected from rusting to preserve it. This can be done two ways. The first is to use sacrificial zinc anodes bolted to the steel. These will need to be replaced as they dissolve. The second is to use a Biorock active current system, applying a low voltage direct current. This current can be provided by batteries, but they would need to be very frequently changed. The best options would be to use a windmill or solar panel mounted on top of the nearby cliff on Salt Island. Solar would be more efficient and reliable. The current would 1) stop all new rusting, 2) reverse existing rusting by converting the iron oxide back into iron, 3) grow a protective layer of limestone on top of the structure, 4) greatly increase coral settlement, growth, and survival, and 5) increase the fish populations. The Global Coral Reef Alliance is ready to work with the BVI Government and dive operators on such a project. 5. HANS CREEK AND BEEF ISLAND DEVELOPMENT Hans Creek is one of the most important Fisheries Protected Areas in BVI. The waters are remarkably clean and clear for a mangrove habitat, and the seagrasses are unusually lush and healthy, which makes it an unexcelled habitat for juvenile reef fish, lobster, and conch, fueling much of the fisheries in surrounding waters. A long-term study of Hans Creek by the International Centre for Living Aquatic Resource Management identified Hans Creek as one of the richest fish nurseries in the Caribbean. The few remaining mangroves in BVI need to be systematically protected from all development, but there appears to be no policy to do so, instead marinas and golf courses are being approved on mangrove habitat wherever developers wish. The proposed development of Beef Island would place a big boat marina in a shallow semi-dry salt pond, which would require massive excavation of fine mud right in front the channel through which almost all the water of the Hans Creek Marine Protected Area area circulates. The shallow channel would need to be blasted much deeper to allow mega-yachts to enter. All the mud from dredging and excavation right at its inflow point would smother the seagrasses and kill off the fisheries nursery function of Hans Creek mangroves. Even worse, the golf course planned for the mangrove and dry forest area above it would provide a source of nutrients that would deliver the coup de grace. The figure shows that any development in this area is immediately upstream of Hans Creek and would unavoidably destroy it one of BVIs most important fisheries resources and should never be permitted. The Hans Creek Protected Area is indicated in Green, with the sites of the proposed marina and golf course in red. The Red arrows show the major directions of water exchange. Not only should this area be protected, it could even be enhanced. Some of the highest densities of reef fish seen in the Hans Creek Area were crowded around the wreck of a boat on the inside of the barrier reef. That was because the structure provided hiding places and shelter for fish that were otherwise absent. Biorock reef frameworks attract huge numbers of fish, especially juveniles, as well as lobsters (if specifically designed to provide the kinds of spaces they prefer). Solar powered Biorock reef frameworks deployed in the Hans Creek Fisheries Protected Area could greatly enhance its role in restocking the fisheries in the surrounding areas. Experimental use of these new approaches would be an excellent project for the Fisheries Department and for researchers at the College. 6. SCRUB ISLAND DEVELOPMENT The ongoing development at Scrub Island has clearly failed to properly contain the sediment from construction, which can be clearly seen moving under, around, through, and over the silt curtains that were installed there. The passage between Scrub Island and Great Camanoe Island has very strong currents (in fact they are so strong that they need to be documented as a potential site for generating pollution-free renewable energy using vertical axis turbines, which would be a good use for the two excellent recording current meters now sitting unused at the College). This is directly threatening the two best snorkeling reefs near to Tortola, namely Diamond Reef immediately across the channel to the south, and Cam Bay Reef, just across the channel to the North. The figure shows that the west end of Scrub Island, where the massive development is underway (red circle), is located where the currents (red arrows) will carry the sediments and damage the excellent reefs (shown in green) that are so close to it. These two reefs are some of BVIs major ecotourism resources, and is just astonishing that such a poorly executed development could be allowed to imperil them, and that such developments are allowed in general without serious independent environmental assessment or a national policy to protect all coral reefs from being impacted by development. These two reefs have some of the highest coral cover now to be found in the region, and even more important they are some of the few locations remaining anywhere in the Caribbean where healthy elkhorn and staghorn coral are making a comeback. Diamond Reef is furthermore the site of the major long-term coral reef monitoring program in BVI. It deserves the fullest possible protection.
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