About Our Coral Reefs
Coral reefs are a precious resource in the ocean because of their beauty and biodiversity.
Coral reefs also provide shelter for a wide variety of marine life, humans with recreation, a valuable resource of organisms for potential medicines, create sands for beaches, and serve as buffers for shorelines.
Coral reefs develop when by millions of coral polyps, small colonial animals resembling overturned jellyfish that use excess carbon dioxide in the water from the atmosphere and turn it into limestone at a satisfactory location.
Corals are animals that are relatives of jellyfish and anemones. Corals can exist as individuals or in colonies and communities.
Corals live in two groups: hard coral and soft coral. Hard corals, or stony corals, produce a rigid skeleton made of calcium carbonate (CaCO3) in crystal form called aragonite, with reef-building capabilities. Soft corals do not produce a rigid calcium carbonate skeleton and do not form reefs, though they may be present and provide beauty to a reef ecosystem.
The soft corals are an order of corals that do not produce calcium carbonate skeletons and are not reef-building corals, so they do not lay new foundations for future corals. Soft corals contain minute, spine-like skeletal elements called sclerites. Sclerites give corals some support and produce a texture that deters predators.
Scleractinia, or stony corals, are exclusively marine animals. Hard Corals are very similar to sea anemones but generate a hard skeleton. They are part of the framework of coral reefs formed by Scleractinia’s. Colonial corals are found in clear, shallow tropical waters and are the primary reef-builders. Solitary corals are found in all regions of the oceans and do not build reefs.
Most soft corals thrive in nutrient-rich waters with less light intensity. They utilize zooxanthellae a significant energy source and most readily eat any free-floating food out of the water column.
More is known about shallow-water coral reefs in tropical zones than deep-water reefs discovered recently.
Corals are found throughout the oceans and at all levels from deep, cold waters to shallow, tropical waters. The shallow coral reefs have optimal growth rates in warm water ranging from 70-85°F (21-29°C). Coral reefs exist depths exceeding 91 m (300 ft), but the real reef-building corals grow best at shallower depths. The most prolific reefs occupy depths of 60-90 ft, and many of these shallow reefs have degraded for several reasons. Corals need saltwater to survive, so they do not grow where there is fresh water runoff. Other factors are the availability of hard-bottom substrate, availability of foods like plankton, and the presence of other organisms that help control macroalgae, like urchins and herbivorous fish.
Imagination Reef Project
The Imagination Reef Project, located in the Key Biscayne Special Management Zone, is under the control of the Department of Environmental Resources Management. Here, fishing gear is restricted, which evades potential impacts of unrestrained fishing pressure, while keeping most recreational uses of the site. The reef deployment location is 40 feet below the surface on a sandy bottom that is at the moment with no measurable seagrasses or fish habitats. This location represents favorable conditions to support our reef, as coral colonies usually only grow in shallow water, often no deeper than 150 feet. This occurs due to the algae that live in most coral polyps and are vital to corals life. Algae need sunlight to survive, so the corals do not grow in water deeper than sunlight can penetrate. The reef contains elevated structures for transplantation of hard or soft corals, which may enhance a faster coral growth. This is because coral recruitment increases significantly when in stable structures that are high enough to minimize burial or abrasion.
Additionally, the size of the reef has an area footprint of 440.000 square feet of the ocean floor. Time has demonstrated that the permitted construction site can make a tremendous contribution to marine life development.