Coral Reefs

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What are Coral Reefs?

The mention of coral reefs generally brings to mind warm climates, colorful fish and clear waters. However, the reef itself is actually a component of a larger ecosystem. The coral community includes a collection of biological communities, representing one of the most diverse ecosystems in the world. For this reason, coral reefs often are referred to as the “rainforests of the oceans.”

Corals themselves are tiny animals, which belong to the group cnidaria (the “c” is silent). Other cnidarians include hydras, jellyfish and sea anemones. Corals are sessile animals, meaning they are not mobile but stay fixed in one place. They feed by reaching out with tentacles to catch prey such as small fish and planktonic animals.

Corals live in colonies consisting of many individuals, each of which is called a polyp. They secrete a hard calcium carbonate skeleton, which serves as a uniform base or substrate for the colony. The skeleton also provides protection, as the polyps can contract into the structure if predators approach. It is these hard skeletal structures that build up coral reefs over time. The calcium carbonate is secreted at the base of the polyps, so the living coral colony occurs at the surface of the skeletal structure, completely covering it. Calcium carbonate is continuously deposited by the living colony, adding to the size of the structure. Growth of these structures varies greatly, depending on the species of coral and environmental conditions– ranging from 0.3 to 10 centimeters per year. Different species of coral build structures of various sizes and shapes (“brain corals,” “fan corals,” etc.), creating amazing diversity and complexity in the coral reef ecosystem. Various coral species tend to be segregated into characteristic zones on a reef, separated out by competition with other species and by environmental conditions.

Virtually all reef-dwelling corals have a symbiotic (mutually beneficial) relationship with algae called zooxanthellae. The plant-like algae live inside the coral polyps and perform photosynthesis, producing food, which is shared with the coral. In exchange the coral provides the algae with protection and access to light, which is necessary for photosynthesis. The zooxanthellae also lend their color to their coral symbionts. Coral bleaching occurs when corals lose their zooxanthellae, exposing the white calcium carbonate skeletons of the coral colony. There are a number of stresses or environmental changes that may cause bleaching including disease, excess shade, increased levels of ultraviolet radiation, sedimentation, pollution, salinity changes, and increased temperatures.

Because the zooxanthellae depend on light for photosynthesis, reef building corals are found in shallow, clear water where light can penetrate down to the coral polyps. Reef building coral communities also require tropical or sub-tropical temperatures, and exist globally in a band 30 degrees north to 30 degrees south of the equator.

Love your Coral Reef

Coral reefs and their associated communities of seagrasses, mangroves and mudflats are sensitive indicators of water quality and the ecological integrity of the ecosystem. They tolerate relatively narrow ranges of temperature, salinity, water clarity, and other chemical and water quality characteristics. Reefs thus are excellent sentinels of the quality of their environment. Proper monitoring of reefs can identify changes in water quality or impacts from land-based activities. Monitoring changes in water quality can help local resource managers understand the implications of actions occurring in watersheds that are associated with particular coral communities. These connections will help in development of sound management plans for coral reefs and other coastal and marine resources.

Coral reefs provide habitats for a large variety of organisms. These organisms rely on corals as a source of food and shelter. Besides the corals themselves and their symbiotic algae, other creatures that call coral reefs home include various sponges; mollusks such as sea slugs, nudibranchs, oysters and clams; crustaceans like crabs and shrimp; many kinds of sea worms; echinoderms like star fish and sea urchins; other cnidarians such as jellyfish and sea anemones; various types of fungi; sea turtles; and many species of fish.

Man has had a long association with reefs. They are important fishery and nursery areas, and more recently have proved to be very important economically as tourist attractions. Reefs provide protection from erosion to coastlines and sand for beaches. However, reefs located near coastal populations are showing increasing signs of stress and are not faring as well as reefs, which are more distant from centers of human population.

There are two types of stresses associated with reef systems: natural and human-induced. The effects of these stresses can range from negligible to catastrophic. Reefs display a surprising adaptation to short-term natural catastrophic events, such as hurricanes, and usually recover to normal community structure. These natural events can even be considered beneficial in regards to biological diversity. Severe storm events on land can topple large trees. This opens up the forest to re-colonization and results in a greater diversity of plants. This same process occurs with storm impacts to reefs. The damaged area of the reef is often re-colonized by a greater diversity of organisms than existed before the storm. In the long term this event benefits the ecological integrity of the reef.

However, reefs are not well adapted to survive exposure to long-term stress. Some examples include agricultural and industrial runoff, increased sedimentation from land clearing, human sewage and toxic discharges.In the Florida Keys, reef growth results from topographical controls that shield corals from the waters of Florida Bay. Florida Bay, although large, is also shallow and has restricted flow. This causes the waters to fluctuate in water quality characteristics which are important for reef growth. Florida Bay waters can vary widely in salinities and become turbid from transport of sediments. Bay water temperatures can also fall above or below those temperatures preferred by corals. Reefs thrive best in the shadow of the islands. These islands effectively form a barrier from direct exposure to the restricted waters of Florida Bay. The shelf areas between islands or at wide passes only support poor coral populations.

Many land-based activities have important implications for reefs. Agricultural activities can introduce herbicides, pesticides, fertilizers and runoff from animal feed lots. Sewage discharges can introduce nitrogen and phosphate compounds along with pathogens and mixtures of toxins. Uncontrolled land clearing can result in erosion, with the resultant increase in sediment loads to surface waters. Roadways, parking lots and buildings consist of impervious surfaces. These surfaces increase runoff rates and carry with those waters mixtures of dissolved substances to surface waters. The surface waters in any watershed eventually discharge into coastal or near-coastal waters. These waters can then impact coral communities associated with these discharge points. Thus, activities occurring in distant locations have impacts to reefs, which are far away from these activities.

There have been increasing efforts to establish better management and conservation measures to protect the diversity of these biologically rich areas. Management practices have historically focused on the coral reef proper and not considered associated communities, such as seagrasses, mangroves and mudflats or defined watersheds (which transport complex mixtures in their waters), in a meaningful manner. This attempted to manage the reef in isolation, like an island.

When reefs are considered as part of a larger watershed, the recognization of the complexity of environmental stressors can be understood. Management plans can be developed to lessen impacts to mangroves, seagrasses and the reef ecosystem, based upon scientific data and a better understanding of the system.

3 Types of Mesoamerican Reefs

Fringing Reef

Barrier Reef

Atoll

Our Philosophy

Living on Long Caye is existing on a private island where you are an integral part of the eco-system.  You are part of how the island and the community stays healthy.  The Community on Long Caye (the development itself) is designed to promote and sustain the health of the surrounding tropical reef and jungle environment. Residents and businesses, understand that by honoring the Eco-guidelines we can “have our cake and eat it, too” by respecting the natural assets. Your parcel and home is a part of the overall design of all-encompassing, unsurpassed access to an extraordinary ecological system while ACTIVELY preserving the the Caye and its surrounds.  We have designed the community with a long term vision.

All of Long Caye is essentially a preserve. Stewardship of the surrounding environment is a core value for us. We take a long term, holistic approach to building community on Long Caye, through the mindful, yet aggressive, adoption of leading edge environmentally friendly technologies. We seek to demonstrate to the world the achievements possible when people, passion and technology team up with nature to create an extraordinary living and visiting experience. Our Conservation Ethos is enacted in perpetuity by the Eco-Guidelines – and they ensure that Long Caye will be here for future generations. As stewards of the atoll, we will not sacrifice our ecological standards or compromise our principals.

We hope to bridge the gap between the enjoyment of access and conscientious preservation of the natural environment – to prove that environmental assets can be preserved, protected AND enjoyed in a fashion that actually promotes the long term health of such assets for the greater good. Community and Conservation priorities are fulfilled with a deep and abiding respect for the Local Culture that has preceded us for centuries in the Lighthouse Reef atoll. We are friends, supporters and business partners to the fishers that have responsibly used the Lighthouse Reef for their livelihood for generations. We understand and promote sustainable business in the Atoll and on the Caye.