Tuesday, September 2, 2008

Coral Reef: The Tropical Rainforest of the Oceans

Coral reefs (the tropical rainforests of the ocean) around the world are dying. 20% of the world’s coral reefs have been effectively destroyed with no immediate prospects of recovery. Fortunately for us, approximately 40% of the 16% of reefs that were seriously damaged in 1998 are either recovering well or have recovered. Unfortunately for us, 24% of the world’s reefs are under imminent risk of collapse through human pressure; and a further 26% are under a longer term threat of collapse.

A report from the World Resources Institute (WRI) in 1998 suggested that as much as 60% of the earth’s coral reefs are threatened by human activity. The most dangerous of these activities and events are coastal development, overfishing, inland pollution and global climate change.

Coral reefs are one of the most neglected of ecosystems; yet, it is also one of the richest in biodiversity. Besides being a treasure trove of biodiversity, colour, variety, and spectacular beauty; they also protect shores from the impact of waves and storms; provide benefits in the form of food and medicine; and provide economic benefits from tourism.

The 2004 edition of Status of Coral Reefs Around the World lists the following top 10 emerging threats (p.19) in these three categories:


Global Change Threats

These are coral bleaching caused by elevated sea surface temperatures due to global climate change; rising levels of CO2; and diseases, plagues and invasives linked to human disturbances in the environment.

Direct Human Pressures

These are over-fishing (and global market pressures) including the use of damaging practices (bomb and cyanide fishing); sediments from poor land use, deforestation, and dredging; nutrients and chemical pollution; and development of coastal areas for urban, industrial, transport and tourism developments, including reclamation and mining of coral reef rock and sand beyond sustainable limits.

The Human Dimension - Governance, Awareness and Political Will

These are rising poverty; increasing populations; alienation from the land; poor capacity for management and lack of resources; and lack of Political Will and Oceans Governance

The above-mentioned Status of Coral Reefs Around the World, 2004 also notes (p. 21) that “The major emerging threat to coral reefs in the last decade has been coral bleaching and mortality associated with global climate change.”

Coral bleaching is one of the main ways that coral reefs can die. Coral reef bleaching is the whitening of the creature due to reduction of photosynthetic pigment. The corals themselves are translucent and get their color from the symbiotic algaes that live inside them.

Bleaching conditions that last longer than ten weeks usually lead to the death of the coral. It can be caused by a change in sea temperature, sedimentation, freshwater dilution, and many other things too.

Another threat that causes bleaching is destructive fishing practices, such as dynamite or poison fishing.

It is a common belief in scientific circles that all species or corals were adversely affected by high sea-surface temperatures during 1998 which led to global coral bleaching and mortality. The second worst year for coral bleaching on record is 2002. Scientists are pessimistic and expect some reefs to vanish by 2020. Greenpeace points to additional scientific research to bolster their claim that climate change will eliminate reefs in many areas.

If climate change is not stopped, coral bleaching is set to steadily increase in frequency and intensity all over the world until it occurs annually by 2030 - 2070.

This would devastate coral reefs globally to such an extent that they could be eliminated from most areas of the world by 2100. Current estimates suggest that reefs could take hundreds of years to recover. The loss of these fragile ecosystems would cost billions of dollars in lost revenue from tourism and fishing industries, as well as damage to coastal regions that are currently protected by the coral reefs that line most tropical coastlines.

Coral reefs are such an important issue; I will be continuing this in my next bog. Stay tuned – I’ll tell you how you can help save the world’s coral.

1 comment:

Anonymous said...

As a diver, scuba and other, and an avid lover of water, this is an important issue for me. I-Max has a great movie of the subject. Sad, but important to be informed.

The last time I was in Jamaica (Ocho Rios) I was shocked to see all the coral within shore range was dead. Every day when I went swimming and diving, I took a bag down with me and picked up trash from the sea floor. The Natives who swam with me were shocked that a (they perceived as) "rich" tourist would spend vacation time picking up trash. They did not join in. The trash primarily came from the cruise ships that dump their trash overboard. Finally I came up with the 'hook' that got them to participate. I said, "If you want to make money off the water, you have to take care of it." The next day they all had bags down there picking up trash. In addition the the serious effects of dead coral, the lack of beauty and other sea life and the 'yuck' factor from diving in a trash heap, one of the things that happens when the coral dies is that other creatures take over, like the spiky sea annenomes (sp?) that make it impossible to use the waters without injury and pain.