CORAL REEFS – A Natural Resource important to Caribbean Islands.
Coral reefs are marine, underwater, diverse ecosystems which contain
structures made from calcium carbonate secreted by corals. Corals are
colonies of tiny living animals found in marine waters containing few
nutrients and amazingly flourish in such conditions. Most coral reefs are
built from stony corals, and are formed by polyps that live together in
groups. The polyps secrete a hard carbonate exoskeleton which provides
support and protection for the body of each polyp. Reefs grow best in warm,
shallow, clear, sunny and agitated waters. They are most commonly found at
shallow depths in tropical waters, particularly in the Pacific Ocean, but deep
water and cold water corals exist on a much smaller scale.
One of the most famous reefs in the Caribbean is Buccoo Reef in Tobago
and Jacques Cousteau ranked this as the third most spectacular Reef in the
world.
AN ARIEL VIEW OF TOBAGO’S BUCCOO REEF & NYLON POOL.
The three most commonly found reefs include: Fringing reefs – reefs that
are directly attached to a shore or borders it with an intervening shallow
channel or lagoon. Barrier reefs – reefs separated from a mainland or island
shore by a deep lagoon and Atoll reefs – more or less circular or continuous
barrier reefs extending all the way around a lagoon without a central island.
Often called “rainforests of the sea”, coral reefs occupy less than 1% of the
world’s ocean surface, yet they provide a home for 25% of all marine
species. Reefs are home to a large variety of other organisms, including
fish, seabirds, sponges, Cnidarians (which includes some types of corals and
jellyfish), worms, crustaceans (including shrimp, cleaner shrimp, spiny
lobsters and crabs), molluscs (including cephalopods), echinoderms (including
starfish, sea urchins and sea cucumbers), sea squirts, sea turtles and sea
snakes. Aside from humans, mammals are rare on coral reefs, with visiting
cetaceans such as dolphins being the main exception. A few of these varied
species feed directly on corals, while others graze on algae on the reef and
participate in complex food webs.
ANIMALS FOUND IN CORAL REEFS
Generally, fish that swim in coral reefs are as colorful as the reef itself.
Examples are the beautiful parrotfish, angelfish, damselfish, and butterfly
fish. At night, some change to a less vivid color. Other fish groups found on
coral reefs include groupers, grunts and wrasses. Over 4,000 species of fish
inhabit coral reefs.
Coral reefs deliver ecosystem services to tourism, fisheries and shoreline
protection. The annual global economic value of coral reefs has been
estimated at $30 billion. However, coral reefs are fragile ecosystems, partly
because they are very sensitive to water temperature and salinity. Almost
60% of the world’s reefs are threatened by human activities including
coastal development, destructive fishing practices such as blast fishing and
cyanide fishing for aquarium fish, over exploitation of resources and marine
pollution. They are under threat from climate change, global warming, ocean
acidification, and harmful land-use practices. High nutrient levels such as
those found in runoff from agricultural areas can harm reefs by encouraging
excess algae growth. Reefs are also smothered by silt from soil erosion, and
red mud bauxite waste, dust and cement from land construction. Coral reefs
are also destroyed by anchors and visitors of the reef who break off coral
as souvenirs. Scientists estimate that 10% of the world's reefs have been
completely destroyed, while another 30% are threatened. In the Philippines,
where coral reef destruction is the worst, over 70% have been destroyed
and only 5% can be said to be in good condition. What has happened to
destroy all of the reefs? Humans have happened.
Damaged coral reefs.
The most obvious sign that coral is sick is coral bleaching. That is when
either the algae inside die, or the algae leave the coral. The algae are what
give coral its color, so without the algae the coral has no color and the white
of the limestone shell shines through the transparent coral bodies. People
have been noticing coral bleaching since the turn of the century, but only
since the 1980s has it gotten really bad.
The image above shows an undamaged, healthy coral reef and a bleached
reef.
If we do not make immediate efforts to save our coral reefs, they will not
be there for future generations to enjoy. We have the responsibility of
caring for our environment and making sure that we hand it over to future
generations in a good condition. If we do not save our coral reefs then we
face the following possible consequences: severe damage to our coastlines
from tropical storms, marine food webs would be threatened and many fish
species will die eventually affecting the species fished for food and
ecotourism would decline and this could affect the country’s economy.
As a country, we can educate our citizens about the importance of coral
reefs. This could be done via documentaries, pamphlets, newspaper articles
and workshops in the various parts of the country. The government should
pass laws prohibiting reef visitors from removing coral and only allowing
trained tour guides to take people to the reef. They also need to ensure
that pollution is minimized by providing proper sewage treatment, demanding
that farmers use only as much fertilizer and pesticide as needed, conserve
soil through crop rotation, replanting trees after harvesting to prevent “runoff” and limiting deforestation. We could further reduce pollution by
replacing fossil fuels with alternative sources of energy such as wind energy
and implementing the three Rs, reduce, reuse and recycle. We have the
power to make a difference.
Submitted by Samantha Ramphal, 1J.