The
REAP Report --- Our Coral Reef
By
Bruce Gray
During
this holiday season and school summer break our beaches will
see increased human use as we go for a cooling swim or just
to relax with family and friends. And while enjoying these beach
activities it is good for us all to remember how important the
coral reef is to our everyday existence as a small island nation.
Coral
reefs are important to our coastal system. Among the most ecologically
most diverse systems in nature, coral reefs play an important
role in the protection and formation of our beaches. A living
coral reef is made up of many tiny animals called coral polyps.
These animals secrete limestone to surround themselves with
a hard skeleton which joins together to form the coral reef.
A healthy coral reef is home to many different plants and animals
such as algae, sponges, worms, starfish, sea urchins, crayfish,
octopus and fish.
There
are two basic types of coral. Stony or hard corals are the main
reef builders requiring warm clear waters to grow. Coral reefs,
even a dead coral reef, are especially important to beaches
because they protect the shoreline from high waves.
Coral
reefs are equally important to our beaches because they act
as a sand source. For example, the parrot fish, butterfly fish
and trigger fish can bite off chunks of coral, digesting the
living material and excreting coral sand. As a result of this
feeding process sand is formed for our beaches. Coral reefs
are vulnerable to natural forces and many human activities.
Waves generated by storms and cyclones can break off large pieces
of coral. A beautiful reef can be transformed overnight into
a bare rubble reef. Rising sea level temperatures can give rise
to coral bleaching whereby corals turn white. Large influxes
of fresh water from heavy rains and run-offs can also damage
the coral. Rain erodes the land and washes the soil into the
sea. The soil then becomes deposited on top of the coral reef
and in effect smothers the coral to death. Pollution, resulting
from sewage or water draining from a field treated with pesticides,
also poses a major threat to the coral. It may take many years
before the resulting damage to the coral reef is manifest on
the beach and the increased beach erosion becomes noticeably
evident.
It
should be everyone's goal to preserve and protect our coral
reefs be they a private individual, developer, fisherman, diver,
or government agency for our islands' future depends on a healthy
coral reef. (Reference source: Coping
with beach erosion by Gillian Cambers, UNESCO/CSI )
Cook
Islands News, 6 January 2003
