Sand Dollar Beach Rocks

George Town, Exuma, Bahamas   N23° 30.926′    W75° 44.829′   Depth 0-4ft.

Look for two dark spots in the water on the north end of Sand Dollar Beach. This is similar to the site off Black Point that is marked with a yellow dinghy mooring ball; but this one is just past the next point of land going south.  There are two groups of small coral heads, rocks and gorgonians.  It’s an excellent protected site for inexperienced snorkelers and children because it is very shallow and close to the beach.

Dark places in the water just off the beach mark the rocks.

If you just like to float on the surface, this is the place for you.  At low tide you will be scraping your belly if you don’t watch out.  Even at high tide you can easily see just about everything from the surface. There is so much to see that it can be overwhelming, so take a minute and try to pick out some of the common inhabitants.

Bushy or tree-like gorgonians are a prominent feature of this site.  Gorgonians, which also include the sea fans, are not plants, but coral animals.  Some of them may look fuzzy.  This is because the polyps are expanded, feeding on plankon with their feathery tentacles.  When the polyps are retracted the gorgonians look smooth or bumpy.  For more on gorgonians click HERE.

The rocks at Sand Dollar Beach:   Left of #1–Sea Fan,  Left of #2–pink coraline algae,  Left of #3–a cluster of Social Feather Duster Worms,    Below #4–Finger Coral (Porites sp.) the coral on the left is a healthy yellowish-tan color but the coral to the right is being overgrown by an orange encrusting sponge,   Left and right of #5–several gorgonians.
The sea fan’s polyps are very tiny but, like all gorgonians, have eight feathery tentacles.  This sea fan has branches flattened on the outer surface identifying it as a Common Sea Fan (Gorgonia ventalina).

Next look for several species of hard or stony coral.  This is the type of coral that reefs are made of, although the corals you see here are characteristically small because of the environment in which they are growing.  You will be able to identify Mustard Hill Coral (which looks like someone squirted a pile of mustard on a rock), Finger coral (which looks like stubby fingers), Lobed Star Coral (that grows in separated lumps), and a couple of species of brain coral (which, of course, look like brains).

Another view of Sand Dollar Rocks:  #1–Symmetrical Brain Coral (Pseudodiploria strigosa),  #2–Gorgonian,  #3–Turtle Grass (Thalassia testudinum),  Left of #4–Mustard Hill Coral,   Below #5–Finger Coral (Porites sp.).  An orange encrusting sponge covers the rocks below and to the left of the Symmetrical Brain Coral.

All around the rocks and interspersed among them is Turtle Grass.  Unlike most marine plants, Turtle Grass is not an algae but a flowering vascular plant that grows from seeds or by way of tangled rhizomes under the sand.

#1–Lobed Star Coral (Orbicella annularis),   Left of #2–Finger Sponge,   Right of #3–Black Sea Rod (Plexaura homomalla), Left of #4–Branching Fire Coral (Millepora alcicornis),  Below #5–Mustard Hill Coral.  Turtle Grass (Thalassia testudinum) is in the background and some Grunts hang out under the rock on the right.
Symmetrical Brain Coral (Pseudodiploria strigosa) has narrow ridges with no groove on top of the ridge.  The polyps of brain corals are elongated and set into the valleys.  They are usually not expanded during the day.
The ridges of the Grooved Brain Coral (Diplora labyrinthiformis) are wide with a deep groove in the middle.  Behind the brain coral is some Finger Coral (Porites sp.) with one red Finger Sponge growing between the coral fingers.  A Christmas Tree Worm pokes its gills out of the brain coral.
The cup-like corallites of the Elliptical Star Coral (Dichocoenia stokesi) are relatively large and elongated.  The polyps are now fully retracted into their corallites but will come out to feed at night.

It is probably best for you to learn to identify Fire Coral right away so that you can avoid its sting. The sting is not usually dangerous but it can leave a welt.  Fire Coral takes many different forms but on these shallow reefs it is usually the branching species that often found often overgrowing dead Gorgonians.  Fire Corals can be identified by their orange or tan color with white tips and the smooth texture that does not have individual cups for each polyp.

#1–Branching Fire Coral,  Below, left and right of #2–Green Bubble Weed (Dictyosphaeria cavernosa), Below#3–Corkscrew Anemone (Bartholomea annulata),   Right of #4–Encrusting orange sponge, Below #5–a small colony of Finger Coral (Porites sp.),   Below #6–The 2 connected tubes are the incurrent and excurrent siphon openings of a coral boring clam.

As you swim around the rocks things will catch your eye.

Once you spot the first one, you will see many Giant Anemones (Condylactis gigantea).  The tips of the tentacles are often bright pink but can be other colors.  This rock is covered with Lobed Star Coral which characteristically grows in discrete lumps.
The sea anemone is like a very large coral polyp with more tentacles and no skeleton.  It attaches its base under a rock or in a hole, and extends tentacles full of stinging cells, called cnidoblasts,  to capture crustaceans or fish that blunder into them.  The prey is guided to the mouth hidden in the center of the tentacles.
A  tree branch or fallen dead Gorgonian looks like a long caterpillar when it is covered by Fuzzy Finger Algae (Dasycladus vermicularis).  The long skinny fish are juveniles of a wrasse called the Slippery Dick (Halichoeres bivittatus).
The Ball Sponge (Ircinia strobilina) has oscula (water outflow openings) in clusters, usually near the top of the sponge
The Pen Shell (not sure what species this one is) is a large clam that is found partly buried in the bottom.  This one is pretty clean.  They are often covered with algae and other growth.   Someone told me that they were not very good to eat.

The shallowness of this site allows you to peer into holes in the rocks  without diving down.

Long orange or white tentacles mark the presence of a Rough File Clam (Ctenoides scabra) next to a rope sponge.
The Reef Urchin (Echinometra viridis) is identified by the light rings around the base of the spines.

Be prepared to find that someone is peering back at you.

The eye belongs to an octopus who moved around to look out at me when it noticed that I discovered its den.
Right below the octopus den, I found the remains of its crab dinner.  Sometimes the nicest, most cleaned-out shells can be found in the octopus’s rubbish heap.
A Spotfin Burrfish (Chilomycterus reticulatus).

For me, the main attraction at Sand Dollar Rocks is the numerous and large Christmas Tree Worms.

A large Mustard Hill Coral with the several Christmas Tree Worms (Spirobranchus giganteus) on it. These worms make a hard shell tube that is overgrown by the coral.
The “Christmas trees” are the worm’s gills and feeding apparatus.  The wormy part resides safely in the tube.  The gills will quickly retract into the tube if you get too close.  In this picture you can also see the orange osculum (water outflow) of a rock-boring sponge and the tiny expanded polyps of the Mustard Hill Coral.

All those pretty little flowers you see around are really Feather Duster or Fan Worms.

Bouquets of Social Feather Duster Worms ( Bispira brunnea) are attached to rocks and sponges.  Like the Christmas Tree Worm, what you see are the gills which range in color from white, orange or purple to variegated. These worms live in soft tubes into which they can retract the gills.
This is a Splitcrown Feather Duster Worm (Anamobaea oerstedi) on some Mustard Hill Coral. This worm also lives in a soft tube and comes in many colors.
The Variegated Feather Duster Worm (Bispira variegata) is found on the bottom close to a rock.
They are small and hidden in the rock, but the Yellow Fanworm (Notaulax occidentalis) is bright.

And if you are lucky you will see one of these before you bump into it.

An eight or nine inch Bearded Fireworm (Hermodice carunculata). is wrapped around a small gorgonian.
The Fireworm feeds on gorgonians and coral.  It has irritating bristles that will get left in your skin if you bump into it.

It is amazing to me how life on the Sand Dollar Rocks stays intact.  It is so shallow and subject to sand shifting and abrasion.  I was afraid that the recent hurricanes might have spoiled it but—here it is.  Still one of the best places I know of to introduce people of all snorkeling experience levels to marine life.

 

 

 

 

 

 

2 thoughts on “Sand Dollar Beach Rocks”

  1. Wow! I often sat in the kayak over these shallow reefs. Can’t wait to get back there. I have new things to look for! And now I have names for different coral and grasses.

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