Marine Environments
of the Caribbean
Scientist estimate that 80% of
all “life forms” on Earth are
found only in the ocean.
Several phyla and thousands
of species are found nowhere
else on the planet. Coral reefs
harbor diverse assemblages of
corals, tunicates, molluscs,
bryozoans, sponges, and
echinoderms that are not rep-
resented in terrestrial systems. A small fraction of coral reef biodiversity is
known and few deeper biological mysteries of these creatures lives have been
discovered. 
The Caribbean hotspot is a diverse
marine system including some 60
species of corals and about 1,500
species of fishes, 23% of which are
Caribbean endemics. Coral reefs, sea-
grass beds, and mangroves shelter,
feed, and nurture billions of larval and
adult organisms. Seagrass beds have the
highest rates of primary productivity
around the world and represent an important habitat
within the hotspot for endangered manatees and turtles.
Elkhorn coral, the primary nearshore reef-builder was
decimated in the last two decades by hurricanes and disease. Recent studies link
terrestrial microorganisms with several coral diseases, but the link to human
activities is still being investigated.
As a result of the unique structure,
chemistry, and properties of marine
creatures, their value in marine
biotechnology––the development of
new health and life-saving drugs––is
growing into a tremendous business.
The anti-viral drugs Ara-A and AZT
and the anti-cancer agent Ara-C were
developed from extracts of sponges
found on Caribbean reefs. Sponges,
that can regenerate from small
pieces, are a promising group of
organisms which have already yielded impor-
tant products. In Japan, a leader in marine
biotechnology, about 20% of the sponge
species tested were found to contain biologi-
cally active compounds. Other products are
under trial for use in treatment of breast can-
cer, liver cancer, tumors, and leukemia. 
Seascapes, Landscapes,
Biodiversity, and Humans
Coral reef ecosystems have enormous value as
natural resources, with additional potential as
a source of lifesaving and life-enhancing
products, yet these facts are unknown to the
general public and government policymakers.
Unfortunately, global warming, poor
and inappropriate land-use activities,
commercial marine exploitation, dis-
ease, and natural catastrophes like
hurricanes may eliminate these
species long before we discover the
miracles they hold. The place
between the natural worlds of land
and water is a sharing of space and
blending of features that creates a
unique, variable, and diverse envi-
ronment. Here in the islands of the
Caribbean, the influence of the sea
envelops the land, creating a connect-
ed world from ridge to reef.
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Rocky coasts are an extreme environment.
Algal community on sand.
Little blue herons are
common shore birds.
A small hawk
waits for a meal.
Fire Coral has become a
dominant coral on reefs. 
Waterlemon Cay, St. John with
Little Thatch Cay and Tortola behind.
John's Folly Salt Pond, St. John.
Coral Bay sunrise.
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