Coral Reef Threats

Coral Reefs and How They Are Threatened

To truly appreciate a Bahamas snorkeling tour, it is helpful to know more about the coral reefs that are the focus of the experience.

Located throughout the tropical seas, coral reefs are large living structures that support an enormous variety of marine life. They also help to protect coastal regions from storms by preventing erosion as well as loss of life and property. Made largely from the limestone skeletons secreted by stony corals, reefs are diverse and productive ecosystems that resemble bustling undersea cities.

Coral reefs require sunlight and warm water to grow, and are normally found only within 30 degrees north and south of the equator. The reefs in the Bahamas are exceptions, existing due to warm currents from the Gulf of Mexico.

Unfortunately, coral reefs are under threat from a number of sources both direct and indirect.

Natural occurrences such as massive waves from storms can cause physical damage, breaking off or flattening parts of coral reefs. Direct threats also include incidents involving boat propellers hitting and breaking coral, and boat anchors dragging across a reef's surface. Careless swimmers and divers can trample soft corals and damage the structure of reefs. Monitoring and limiting the number of divers on a reef and anchoring boats on buoys instead of reefs can help prevent this type of direct damage.

Indirect threats to coral reefs are more difficult to measure accurately. Stress factors include overfishing and destructive fishing practices such as blast fishing using dynamite, as well as the spread of non-native species that can alter the food chain on reefs. Rising water temperatures can cause a condition called coral bleaching in which the coral expels the algae that give it its color. Degradation of water quality due to the chemicals in storm water runoff can have a profound impact on the complex ecosystems of coral reefs, which need clean water to survive. Fertilizers, for example, can cause algae blooms that reduce sunlight, smothering living coral.

The stressors impacting coral reefs may be outpacing their ability to recover. Some scientists maintain that 10% of the world's reefs have been damaged beyond recovery due to natural and human causes. Fears are that if the present trend continues, many more reefs may be gone in less than 40 years.

Organizations that are working to save coral reefs offer a number of practical suggestions to help in this effort. These include eliminating the use of chemically enhanced pesticides and fertilizers when possible, and the use of conservation methods to reduce waste water. It is also important to avoid leaving garbage on beaches, especially plastics, which can break coral and strangle marine life.

To help preserve the health of the reefs for future Bahamas snorkeling adventures as well as the biodiversity and beauty of the planet, snorkelers and divers are reminded to avoid touching or standing on coral reefs, and never break pieces of coral off the reef to collect as souvenirs.