Coral reefs are among the biologically richest ecosystems on earth. They are a source of biodiversity, food, environmental protection, recreation, and potential medicinal products. Throughout much of the world, communities and governments are dependent on them for subsistence, jobs, products, and revenue. Tragically, as important as they are, coral reefs are also under an ever-increasing threat due to global warming, coastal development, destructive fishing practices, and other human-related activities.
The many benefits of reefs
Dubbed " the rainforests of the sea," coral reefs consist of about 800 species of stony corals. They are home to about 4,000 species of fish (more than a quarter of all known marine fish species), as well as an incredible variety of sponge, mollusks, and other invertebrates. And that is only the known species, for there are many yet to be discovered. Coral reefs and associated habitats also help to support important charismatic species that are loved the world over, such as marine turtles, dugongs, rays, whale sharks, and others. Estimates of total diversity of reefs range up to 2 million species.
In recent years scientists have begun to more closely examine the biodiversity of coral reefs in search of cures for human diseases. Coral reefs are especially promising because the chemicals that many of them produce may contain important biochemical compounds. Recently, up to one-half of all new cancer drug research focused on marine organisms, and much of this targeted coral reefs.
Besides being rich in biodiversity, coral reefs are productive biologically in volume. In fact, one square kilometer of healthy coral reef can produce up to 37 metric tons of fish.
Most coral reefs are located in developing countries, and much of the world's poor depend directly on reef species for protein. Even though coral reefs occupy less than one quarter of 1% of the marine environment, they contribute about one-quarter of the total fish catch, feeding as many as one billion people in Asia alone.
Additionally, coral reefs protect coastal communities from storms and wave action and reduce the impacts of global warming by incorporating carbon dioxide through photosynthesis and carbonate production. Furthermore, through natural carbonate sediment production, reefs create an important recreational item, thousands of miles of white sandy beaches.
The direct and indirect benefits of reefs have an estimated value of $375 billion each year.
One square kilometer of healthy coral reef in Indonesia is worth an estimated $12,000/year in fisheries production alone.
Therefore, maintaining the health of coral reefs so they can continue to support food production and the employment and income benefits of fisheries is an important issue, especially in developing countries.
Another industry that is important to developing countries is reef-based tourism. Until the September 11 tragedy, tourism was the largest and fastest growing sector of the global economy and it was largely focused on the coast, often in coral reef areas. For example, Florida's 220-mile long reef tract generated $1 billion in annual fishing and tourism revenues. Australia's Great Barrier Reef attracts more than 2 million visitors per year and is worth about $600 million annually.
Reefs also yield a host of other "products." Sand, gravel, and limestone rock are extracted for a variety of construction purposes. Other products include coral and shell jewelry, tourism curios, and of course, marine ornamentals.
Threats to reefs
Despite their importance to humans, or perhaps, because of their importance, coral reefs worldwide are in trouble today.
58 percent of the world's reefs are potentially threatened by human activity, ranging from coastal development, destructive fishing practices, and climate change to over exploitation of resources, marine pollution, and runoff from inland deforestation and farming.
Coral reefs of Southeast Asia, the most species-rich on earth, are the most threatened of any region. More than 80 percent are at risk, primarily from coastal development and fishing-related pressures.
At least 11 percent of the world's coral reefs contain high levels of reef fish biodiversity and are under high threat from human activities. These "hot spot" areas include almost all Philippine reefs, as well as many of the reefs in Indonesia, Tanzania, the Comoros, and the Caribbean.
A large part of the problem is due to the increased size of the human population and their growing concentrations along the coast.
Overall, nearly 40 percent of the world's inhabitants (over 2 billion people) live within 100 km of the sea. Almost half a billion, or 8 percent of the total global population, live within 100 km of a coral reef.
Coastal development near coral reefs poses a range of threats. The most obvious are the human activities that directly destroy reefs, such as the construction of airports and other landfill projects on top of reefs; dredging for harbors; and extracting sand, gravel, and limestone rock for construction materials.
Human activities that indirectly impact coral reefs are even more damaging and widespread.
Coastal development, such as shoreline construction and the clearing of inland watersheds, creates erosion and flooding conditions. Sediment and nutrients that are discharged into reef waters can smother the corals. They also reduce the light levels needed for coral growth and the establishment of new corals. Likewise, sewage and upland sources of excess nutrients, such as agricultural runoff with fertilizer, can create algae "blossoms" that block sunlight and reduce coral growth.
Another pervasive human activity with indirect effects on coral reefs, including those found in remote areas, is unmanaged fishing. Over fishing can cause shifts in fish size, abundance and species composition within reef communities. When nonselective fishing methods are used, large numbers of other species, along with the targeted species, may be swept up in nets or killed by poisons or explosives in the process. The removal of key species may ultimately create ecosystem level changes. For instance, in the Caribbean, excessive removal of algae-eating fish led to algae-domination that has smothered coral in some areas.
Additionally, reefs are directly destroyed by some fishing methods, such as fishing with dynamite, fishing with cyanide and other poisonous chemicals; muro-amin netting (pounding reefs with weighted bags to scare fish out of crevices); and trawling.
Even untrained, careless snorkelers and divers can trample coral reefs, and boat anchoring on coral reefs can cause direct destruction.
Global climate change is another emerging threat to coral reefs. Climate change will likely elevate sea surface temperatures in many places, causing sea levels to rise and increasing the frequency and intensity of storms. Already we have experienced unusually high water temperatures caused by severe El Niño oceanographic events, which are likely due to global warming. These high water temperatures have been linked to the bleaching of corals, which is a phenomenon that occurs when stressed corals expel their zooxanthellae. During a 1998 bleaching event, up to 90 percent of reef coverage was destroyed in some areas. Fortunately, reefs are recovering even after being hit badly by this event.
In many cases, it is difficult to pinpoint the exact causes of the serious declines in coral reef health occurring around the world. Frequently, there is no single cause but a combination of factors that leaves reefs vulnerable to periodic natural disturbances such as temperature extremes, hurricanes, cyclones, and other natural events.
Many argue that of all the threats to coral reefs, the marine aquarium industry is one of the least threatening. In fact, impartial studies have concluded that, in comparison to other extractive and destructive impacts on coral reefs, the effects of collecting live coral for the aquarium trade are very small, and that the global coral trade has "little long term impact."
But the more important point about the marine ornamental industry that we should focus on today is not its innocuousness but rather its great potential to create incentives for larger ecosystem conservation. This ecosystem conservation itself can be the critical element that not only saves biodiversity but also protects the marine ornamentals industry.
Think about it. A threat to coral reefs, regardless of its source, is a threat to the marine ornamentals industry because destruction of coral reefs leads to loss of marine aquarium organism habitat and eventual loss of target species themselves. Threats to coral reefs not only attack biodiversity, they attack the industry as well as numerous local communities around the world that depend upon the coral reefs for their livelihood. Speaking simply, if the reef dies, we would all go under.
The marine ornamental industry; however, has vast potential not only to become sustainable itself but also to create an anchor for broad coral reef protection. This protection will in turn protect not only the industry itself, but other sustainable, reef-dependent activities as well, and create a win-win solution for all coral reef stakeholders.
How the aquarium trade can benefit reefs
The collection, export and keeping of coral reef animals have numerous benefits that are often overlooked by those criticizing the trade and hobby.
Collecting and exporting marine aquarium organisms in developing countries creates jobs and income in rural coastal areas that have limited resources and economic options. There are an estimated 7,000 collectors in the Philippines, many of them supporting families. A UNESCO report estimates the number of people in Sri Lanka directly involved in the export of reef animals is as high as 50,000.
In addition, aquarium animals are the highest value-added product possible to harvest sustainably from coral reefs. Aquarium fish sell for $248 per pound compared to food fish at $3 per pound. Likewise, on average, live coral is worth $3.50 per pound, while crushed coral for lime sells for 3 cents per pound. Collectors, therefore, have strong financial incentives to ensure that stocks of marine aquarium organisms and their environments remain healthy.
Furthermore, in developed countries, public and private marine aquariums depend on wild harvested marine aquarium organisms for 98 percent of the reef animals in their tanks. Often these marine aquariums are a primary source of knowledge about coral reef organisms and ecosystems for the people in these countries. Their existence contributes to conservation awareness for coral reefs worldwide.
On the other hand, the loss of the marine aquarium industry would eliminate jobs, and quite likely, the stewardship incentive. This could leave rural, coastal areas open to more destructive uses and to increased environmental degradation. Eliminating the communities high value-added aquarium fishery would contribute to the poverty that drives people to use destructive fishing practices, such as blasting, to gather food for the community.
Eliminating economic options where few exist can also contribute to the out-migration from rural coastal areas to already over-populated urban areas.
If we all work together we can continue to have healthy populations of fish and corals and save these "Rainforests of the Sea" for present and future generations.