Flower Garden Banks
National Marine Sanctuary
"The Texas
Caribbean"
Located 110 miles off the southern Texas coast in the Gulf of
Mexico is a unique coral reef environment.
Out in the open ocean and 65 feet below the surface a landscape of live coral
coverage rises from the deep. There are three primary reefs here. The Flower
Garden Banks are divided into East and West sections. About 40 miles closer to
the Texas coast is Stetson Bank. All of the reefs in this area are protected be
the National Marine Sanctuary program operated by the National Oceanographic and
Atmospheric Administration (NOAA). The coral reefs rest atop ancient salt mounds
and are accompanied by oil drilling platforms that pepper the distant horizon of
the Gulf of Mexico.
Access
to the sanctuary is limited to a few dive operators in the area. Most of the
activity on these coral reefs stems from research conducted by scientists
associated with various NOAA programs. The Flower Garden Banks and Stetson Bank
are remarkably healthy coral reef ecosystems with live coral coverage exceeding
90% in some areas.
The
East and West Flower Garden Banks are dominated by hard corals. A significant
variety of sponges can also be found in areas not yet colonized by stony corals.
But soft corals are notably absent here.
To date 21 species of hard corals have
been described from the Flower Garden Banks; they are as follows: Montastrea
faveolata, M. annularis, M. cavernosa, M. franksii, Diploria strigosa,
Porites asteroides, Colophyllia natans, Millepora alcicornis, Agaricia sp.,
Stephanocoenia intersept, Madracis decactis, Siderastrea siderea, Mussa angulosa,
Scolymia cubensis, Porites furcata, Madracis mirabilis, and five
others.
Mussa angulosa
Scolymia species
Mixed
plating coral
species
Mussa species
Diploria
species
Madracis species
Invertebrates
like the short spine urchin are quite common actively consuming algae at night.
Another
nocturnally active invertebrate is the Camel Shrimp (Rhychocinetes
durbanensis) which feeds on small crustaceans and worms.
Stetson
Bank is an interesting reef because there are very few corals. It is actually
known as a sponge and algae reef. The fish population here is impressive. There
are many common Caribbean species.
The
French Angelfish (Pomacanthus paru) in the left image displays some
sub-adult features of yellow vertical stripes on the face and body. A full adult
specimen is shown to the right.
The Creole
fish which would be uncommon and found in deep water
along the Florida Keys is here both abundant and a relatively shallow water
swimmer.
With abundant sponge populations there is a wide variety of
small reef fishes that call them home. Here juvenile damsel fish dart in and out
of a blue tube sponge.
Large Rock Beauty Angelfish (Holacanthus tricolor)
can be seen patrolling their territories.
At night, the Scrawled Filefish is most colorful displaying
nocturnal blue and white patterns. They sleep under ledges or nestled between
rock outcroppings.
At depths of 15 to 21 feet (5 to 7 meters) Barracuda are seen
swimming alone or in groups. When approached, these fish will quickly swim away
so their teeth make them appear more ominous than they really are.
Cleaning stations are quite common at both the Flower Garden
Banks and on Stetson Bank. In the photograph above a Spotted Box fish has
parasites removed by a pair of active wrasses.
REEF REPRODUCTION
Once
per year a very exciting event takes place in the Flower Gardens. Every summer
eight days after the full moon in August a mass spawning event occurs with hard
corals releasing billions of eggs into the ocean.
The
eggs are fertilized in the water column by male coral colonies in the vicinity
that recognize the chemical cues produced by the egg release. Small spheres
known as egg bundles are just that, thousands of eggs clustered together that
rise in the water and break open into many individual eggs.
Egg
bundles first appear as they gently rest atop the oral opening of the coral
polyps. Shortly afterward groups of polyps begin releasing the eggs and in waves
the bundles delicately float away from the colony.
This
years event was quite remarkable and memorable for many reasons. Most notable,
little did we know was that it took place just three days prior to the arrival
of 2005's hurricane Katrina! This expedition was cut short a day as Katrina's
clouds filled the sky and the seas roughened in the Gulf.
In
part 2 of this
expedition page we examine the collection of the coral eggs and successfully
rearing them for the SECORE project. These new techniques will usher in the
future of the marine aquarium trade!
