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The Paintings of Liza's Reef
Detail from "The Garden of
Departing Dreams" by Lee James Pantas
Coral Reef Links
Extensive index of important coral reef sites.
Coral Reef Ecology
Coral Reefs of the World
Threats to Coral Reefs
Coral Reef Photography Gallery
Reef Guardian International's Website allows you to send your views easily to
government agencies on key coral reef conservation issues.
Reef Guardian International
INTRODUCTION:
Coral reefs are
universally considered to be one of the crown jewels of our beautiful
planet. Shallow marine habitats, coral reefs are defined both by a
physical structure and by the organisms found on them and are found in
all of the world's oceans, at all depths, and are shallow marine
habitats. They are defined by both a physical structure and by the
organisms called coral polyps that are found on them. These have a very
small cylindrical body, topped with a ring of tentacles which are used
to capture food from the waters around them and as the polyps die, new polyps grow on top of and
next to the dead ones, and this contributes to the gradual slow growth
of the coral reef. Other types of animals and plants, algae, sponges and
mollusks also contribute however the primary building forces are the
living coral polyps. Often referred to as the "rainforests of the sea"
because of their incredible diversity, coral reefs are home to over
4,000 species of fish, 700 species of coral species and thousands upon
thousands of other marine plants and animals.
A great number of corals have developed the ability to live in colonies and to build up a communal structure. Some, known as reef-building or hermatypic corals, build a stony structure out of calcium carbonate. This type of coral reef is almost entirely confined to warm, shallow waters, and it is their limestone skeletons which are critical to coral reef formation. These reef building corals do their work slowly, and some large corals may build up their structure at a rate of just a few millimeters per year, while the faster growing tips of branching corals may grow at rates of 150 millimeters per year or more. Corals can only grow in warm, well lighted waters and require a solid surface or platform on which to grow. These factors restrict the reef building corals to the shallow rocky waters of the tropics
Multi-functional, reefs provide food, shelter and breeding grounds to thousands of ocean species, protect shorelines from erosion, and provide recreational opportunities and sources of income for millions of people who rely on them. Although they cover less than one percent of the ocean floor, they are home to a quarter of the known marine plant and animal species. Twenty five percent!!! That's a lot! And this rich, precious habitat is now being threatened on many fronts. While they are the most spectacular of underwater environments, they are also the most fragile. Coral reefs have evolved over millions of years to cope with natural forces such as hurricanes, floods, ocean currents and diseases, but they are no match for man's destructive patterns and activities. Coastal development, over fishing, coral mining, sewage, fertilizer and chemical pollution, sedimentation, ocean warming and the use of cyanide and dynamite on the reefs as fishing practices are all taking a major toll, and they all can be traced by to man's activities.
Already over eleven percent of the world's coral reefs have been lost to human impact and it is predicted by scientists that over the next thirty years, up to thirty more percent could be lost if intervention does not occur. Over sixty percent of reefs in the world are either now severely damaged and threatened. The loss of these coral reefs around the world would be devastating -not only would millions of people lose their only source of food and income, we would see the extinction of many fascinating and beautiful ocean species, as well as lose the opportunities for advances in science and medicine. Many corals have already provided a number of medical break throughs in HIV and cancer treatments.
GLOBAL DISTRIBUTION:
Charles Darwin is considered to be the first person to prepare a
global map of coral reefs. As a rule, coral reefs are confined to a
broad band, roughly confined to the tropics and circling most of the
planet. Unevenly distributed within this swath, large numbers of reefs
are confined to remote island locations and offshore regions far from
the mainland. Coral reefs are largely absent from the Central Atlantic
and the shores of Western Africa and are greatly restricted along the
Pacific shores of the Americas as well as the coastline of South Asia
from Pakistan to Bangladesh. There are over 280,000 square kilometers of
coral reefs worldwide, and this figure represents only 0.089 percent of
the world's oceans and less than 1.2 percent of the world's continental
shelf. The greatest majority of coral reefs are found in the region
known as the Indo-Pacific, which stretches from the Red Sea to the
Central Pacific. For more information on specific coral reefs of the
world, visit these other sections of my website devoted to coral reefs.