THE CORAL REEFS

•BENEFITS•FUNCTIONS•THREATS•SOLUTIONS

WHAT ARE CORALS?

CORAL IS AN INVERTEBRATEThere are two groups of corals

◦Hermatypes- hard corals◦Ahermatypes- soft corals

HERMATYPES AHERMATYPES

HARD SOFT ( A FEW HARD ONES)

CONTAINS ZOOXANTHELLAE

THESE DO NOT CONTAIN ZOOXANTHELLAE

How are the reefs formed?

The term coral is used to describe the skeletal remains of these animals, particularly those of the hard corals which form the limestone base that becomes the foundations of the reefs.

THE GREAT BARRIER REEF

DID YOU KNOW?The great Barrier Reef is the largest structure built by living organisms on earth and is the only living structure visible from outer space.

THE CORAL BODYA Hollow sac-like structure that appears smaller than a pencil eraserThe body of a coral animal is called

a polyp.

The Coral Body

Polyps of the hard corals extract calcium carbonate from the sea water and use it to build a hard external limestone skeleton beneath and around their base .

This skeleton secures the fragile polyp to a surface and serves as its protection.

Food Source ZooxanthellaePlanktons

◦Phytoplanktons◦Zooplanktons

◦60 % of the planktons on the reefs are eaten by the coral polyps.

◦Most corals feed only at nights.◦Some coral are herbivores and some

are carnivores

Reproduction and Growth

Sexually AsexuallyCoral polyps reproduce

both sexually and asexually

Sexual reproduction occurs when the corals spawn.

They release eggs and Sperms into the water.

The sperm then fertilizes the eggs forming a new creature called a planula.

Asexual reproduction occurs by budding. The parent polyp clones itself by dividing to from a new polyp which remains attached to the parent poly tissue.

A coral colony then develops by the constant adding of the new buds.

BENEFITSThey benefit both man and the environment

They are living organisms.They are beautiful and enrich the life

of the ocean.They provide food and shelter to

thousands of species of plants and animals.

They exchange energy and nutrients with other marine ecosystem.

BENEFITS TO THE ENVIRONMENTPicture to the right shows the island of Bermuda surrounded by coral reefs.

They break waves.Protect the shorelines from erosion.Help to keep beaches and coastal

communities intact.

More Benefits

• Supplies finfish and shellfish upon which the national

economy depends• They provide food• They provide jobs• They provide recreation and entertainment• Provide ornamentals-jobs and income for

tropical fish gathers• They support tourism- snorkel, diving,

boating fishing. • Health- Recent discoveries for treatment

for cancer, AIDS, infection, arthritis, asthma, herpes, and even broken bones

More Benefits

The calcium carbonate from the skeleton of the corals of coral animals is used to produce lime which is added to cement and mortar to help it set more quickly.

The sand on the beach also benefit from coral reefs as it is formed by the breakdown of dead corals and algae.

ThreatsCorals are highly sensitive to

environmental conditionsThey grow best in shallow waterWater must be clear between 68

degrees Fahrenheit and 84 degrees Fahrenheit.

The need normal oceanic salinityThey are being threatened

globally by natural and man-made disasters.

Threats

NATURAL HUMANS

Global warming and the greenhouse effects.◦ Coral bleaching

Sea level changesHurricanesCyclonesAbnormal weather

patternsFluctuations in

seawater temperatures

Human impact is catastrophic

Over harvesting of fishUse of cyanide and

dynamiteNutrients and pesticides

draining into the reefs from agriculture

Boat anchors carelessly being dropped unto the reefs

Deposits of raw sewage

Threats

NATURAL HUMANS

Heavy rains that dilute salinity

Extreme low tidesDiseasesPredator population

explosion, e.g. Crown- of thorns- sea stars.

Tourists and locals stepping on the corals

Coral mining for construction materials

Sedimentation from deforestation

Road constructionOil pollution from

shipping

DAMAGED REEFSIDENTIFY THE CAUSES

SolutionsEducation and ActionReef preservationWhat You can do:Learn about reef preservationVolunteer to help protect your

reefsBe informed about policy making

SolutionsAvoid purchasing products from

coral reefs or their inhabitantsBe a responsible Eco-touristSupport reef conservationsBe responsible when you dive

and snorkelBe a responsible boater and

fisherman

Preserve to Conserve

What are you going to do ?