Travel Reference
In-Depth Information
MARINE LIFE
Corals & Other Invertebrates
Corals are sea creatures in the same invertebrate category as lobsters and octopuses. More
than 40 types rise up in the Virgin Islands, including sea fans and yellow tube sponges.
Each coral is a tiny animal with a great gaping mouth at one end, surrounded by tentacles
for gathering food. A reef is usually composed of scores of coral species, each occupying
its own niche. Each species has a characteristic shape - bulbous cups bunched like biscuits
in a baking tray for the star coral and deep, wending valleys for the well-named brain cor-
al. Deeper down, where light is scarcer, massive corals flatten out, becoming more muted
in color. Deeper still, soft corals - those without an external skeleton - predominate. These
lacy fans and waving cattails look like plants, but a close perusal shows them to be menacing
animal predators that seize smaller creatures such as plankton.
The reefs attract fish and other sea creatures to the delight of divers and snorkelers, but
the ecosystems are extremely fragile and take thousands of years to form. Warming water
temperatures, human encroachment and hurricanes have harmed many reefs in the Virgin
Islands and throughout the Caribbean.
Tiny algae called dinoflagellates provide the spark for bioluminescence at places such as Salt River Bay, St
Croix. The single-celled organisms light up when agitated, such as when brushed with a kayak paddle.
Fish
More than 500 species of fish swim in local waters. Mangrove estuaries and vast coral reefs
are the nurseries and feeding grounds for these tropical creatures. And it's not just sergeant
majors, angelfish and grouper: the Virgin Islands are some of the best places in the world to
get up close and personal with large barracudas, manta rays, moray eels and plentiful nurse
sharks - carefully, of course! Most of the scary-sounding swimmers have a live-and-let-live
attitude, so as long as you leave them alone, they'll return the favor.
Fan favorites for exotic fish include the colorful, bird-beaked parrotfish, the electric-hued
blue tang, the purple-and-yellow fairy basslet, and the pointy longspine squirrelfish.
