You do not need to be a diver to recognize and accept that healthy coral is less common nowadays.
What appears to be a collection of colorful underwater rocks are in fact a garden of limestone coral skeleton heads providing a reef habitat for thousands of tiny living organisms called coral polyps.
Their habitat is so finely balanced and sensitive that coral disease and other syndromes currently threaten their colonies and cause destruction with greater significance and more severe symptoms than ever before.
The plight of coral's continued existence is in danger. Disease, plague, stress, and global human contributions threaten an invaluable commodity that is disappearing faster than it regenerates.
Coral disease is caused by a variety of pathogens, fungi and bacteria. The plaguing microorganisms reproduce so quickly that they can mutate and evolve into deadly disease strains which kill the coral.
White plague coral disease is a typical example of how quickly they can attack coral repeatedly as new strains. Type l white plague made its first big hit in the 1970's and returned as type ll in the mid nineties.
Type lll white plague made its reappearance in 1999.
Corals are vulnerable to stress like people are. We are more prone to illness and disease when we feel physically tired or mentally stressed. The same susceptibility to plagues and diseases is true of coral polyps.
They are at risk from two types of stress and the harm to corals is intensified when both factors are present. Abiotic stress is triggered by factors which are non-living.
For example, the most common causes of abiotic stress are elevating seawater temperatures, pollution, and sedimentation. Biotic stress is generated by living factors. They include viruses, fungi, and bacteria.
The pollutants which humans contribute to rivers and oceans deteriorates water quality. Industrial waste and carbon emissions from driving petrol motorized vehicles is considered to be responsible for increases in the spread of coral disease infection and severity of ocean acidification.
Despite all the references to coral reef death and destruction, they have been around for hundreds of thousands of years. In fact, compared to the evolution of other less fortunate animal species corals are extremely resilient.
Even though they struggle to recuperate from the most severe disease incidents, they generally recover from natural disasters and changes in water temperature.
Nonetheless, the increase in human pursuits such as habitat degradation, dynamite fishing, over-fishing, trawling, and pollution causing activities, all contribute to the multiple perils for coral reef formations.
Healthy polyps are likely to be replaced by more resilient invertebrates such as sponges and algae. This situation could lead to an increase in fish deaths and a worsening of the underwater ecosystem.
The long term odds for coral survival is not good unless significant changes happen very soon.