The Coral Reef Crisis:
Protecting Bermuda's Marine Ecosystems
Dr. Ross Jones, Associate Research Scientist
Coral reefs are in trouble worldwide. Reef researchers have described the current decline in these vital marine ecosystems as the "coral reef crisis," and
some are predicting that close to 60 percent of the world's reefs may be lost within the next 25 years. Recent studies estimate that nearly a third of reefs around the globe are already severely damaged.
The extensive reef system that surrounds Bermuda is of great significance both globally and locally. Bermuda's reefs, which are seeded by coral larvae from Florida and the Caribbean, comprise the most
northerly coral reefs in the Atlantic Ocean and are highly isolated geographically. They serve as an invaluable living barrier that protects Bermuda's shores from waves and storm surge, they contribute to
the economy through tourism and fisheries, and they are a crucial source of marine biodiversity. BBSR's scientists have been investigating the reefs around Bermuda for more than 100 years. These studies
began to focus on environmental issues in the 1970s with the introduction of the Bermuda Inshore Waters Investigation, and later with the Benthic Ecology Research Program (BERP) and the Land-based Sources of
Marine Pollution Program (LBSMP). In 2004, the long-term marine environmental research and monitoring at BBSR was revised to incorporate the recognition of threats posed by global climate change and the ways
these effects can exacerbate problems in the local marine environment. To this end, BERP and LBSMP were amalgamated into the new Marine Environmental Program (MEP), which is funded by the Bermuda Government's Department of Environmental
Protection.The current worldwide coral reef crisis has been variously ascribed to over-fishing, disease, and pollution from agriculture
and land or coastal development, acting either singularly or in combination. More recently, it has become apparent that these changes, which occur largely on local scales, are being intensified at the global
level by the effects of climate change. These effects include the weakening of coral skeletons through changes in ocean chemistry due to higher levels of carbon dioxide in the atmosphere, and an increase in
the frequency and intensity of hurricanes that can damage reefs. However, the most pressing issue associated with climate change is considered to be the increase in the frequency and magnitude over the last
three decades of coral disease and bleaching events, when high water temperatures cause corals to lose the symbiotic algae that enhance their metabolism, respiration, waste excretion and growth rate. The
Caribbean reefs that seed Bermuda's corals have experienced a massive region-wide decline, from approximately 50 percent coral cover to less than 10 percent. This decline will affect coral dispersal and gene
flow to Bermuda, making our reefs more and more geographically isolated. The isolation of Bermuda's reefs is highly significant for the MEP's studies because local coral deaths, whether caused by pollution,
dredging, disease outbreaks, hurricane damage or thermally induced bleaching, will have lasting impacts. Furthermore, the limited genetic variation within isolated populations in marginal environments, like
the North Atlantic, means that they are likely to have a limited capacity to respond to or recover from environmental disturbances. The MEP team monitors and studies Bermuda's coral reefs to discover
potential new sources of pollution; enhance our understanding of the impacts of existing pollution sources; identify the effects of climate change; and delineate between the effects of climate-related
stresses and those unrelated to climate change. This research now comprises four distinct programs, including an education and outreach initiative. In the Ecological Surveys program, we conduct extensive
video monitoring on a yearly basis to assess the cover of hard corals, soft corals, sponges and other key groups at sites in each of the major reef zones and at potential pollution sites, such as the Castle
Harbour dump site and Hungry Bay sewage outfall. Monitoring of the extent and severity of coral bleaching, death and disease is also conducted annually at multiple sites across the Bermuda platform, with the
capacity to rapidly expand the program should a bleaching event or disease outbreak be identified. We survey juvenile coral settlement at multiple locations, including impacted areas such as Castle Harbour,
and conduct other specialized monitoring projects around Bermuda. The second research program, Physico-chemical Analyses, involves measurements of surface waters at predominantly inshore locations around
Bermuda. This includes the collection of data on a suite of parameters, such as dissolved carbon dioxide, nitrates, phosphates and silicate, and on chlorophyll concentrations as an indicator of nutrient
levels in the water. Seawater temperatures are recorded every half hour at locations across the platform using submersible loggers. In time, this program should allow us to detect long-term changes in ocean
temperatures and to better understand the relationship between temperature and coral bleaching. It may also be possible to identify potential acclimation and adaptation of corals to environmental change. In our third research program, Ecotoxicology/Biomarkers and Environmental Contamination, we are investigating the effects of xenobiotics, or compounds that are foreign to the marine environment,
on corals. This program will soon center on a sophisticated dosing system housed in BBSR's new laboratory building. Corals will be exposed to pollutants, such as pesticides, anti-fouling paints,
petrochemicals and trace metals, so we can measure their impacts at different levels using a variety of cutting-edge techniques. In collaboration with BBSR's Air Quality Program, we also
conduct occasional surveys of seawater or groundwater contamination.Fortunately, our coral reef research to date has shown that Bermuda's reefs have fared well in the last decade when compared to the
degradation reported throughout the rest of the world and in spite of four known bleaching events off Bermuda in the last 30 years. For example, monitoring at sites on the northern rim reefs has indicated no
change in hard coral cover since 1992. However, our reefs are constantly threatened by problems associated with Bermuda's extremely high population density and annual influx of tourists. With little
agriculture or heavy industry, local pollution problems are largely associated with the population and the disposal of its waste. In the absence of suitable landfill space, the disposal of bulk waste, such
as cars and refrigerators, is achieved by dumping at a land-reclamation site in Castle Harbour. Household waste is incinerated and mixed with cement to form blocks that are also deposited at this site. This
dumping, along with the disposal of sewage in septic tanks, in boreholes and directly into the sea, represents a potentially significant long-term source of marine pollution that requires close monitoring by
the MEP. In summary, because of our geographic location and dense population, Bermuda's unique coral reefs are at risk. In the last decade there has been a growing realization that global and regional
climate stresses and localized non-climate stresses interact to threaten the health and sustainability of reefs worldwide. While there is no local evidence yet of the crisis-level coral reef degradation that
is occurring elsewhere, BBSR's new Marine Environmental Program has been designed to provide an integrated approach to environmental protection and the issues associated with global climate change, supplying
information that is essential to the successful management of our fragile coral reef ecosystems.
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