Nature News

Holes on The Beach, Part II
In the last issue of The Anchor, Nature Notes discussed several holes that are
naturally occurring on the beach. This article will focus on those holes made
by marine animals.

The Georgia ghost shrimp live underneath the sand near the water’s edge
and are rarely seen (thus the name). Their burrows can be 6 feet deep even
though the opening is about the size of a coin. During high tide, they venture
out of the opening (while still under water), to feed from drifting particles of
organic matter. The “sprinkles” that often surround the hole are not for your
ice cream cone. Those are fecal pellets.

Keyhole sand dollars live just beneath the sand usually near the water’s edge.
Their “slots” allow water to push through, preventing it from being washed
away in the waves. These also help bits of food travel from their topside to
their underside stomach. Sand dollars walk along the bottom of the ocean
with tube feet. The hole shown above indicates a live sand dollar is just under
the surface.

The Atlantic ghost crab burrows holes in the soft sand above the high tide line.
They are typically at an angle and each crab uses 2 holes- an entrance and
an exit hole. They are most active after sunset. They are opportunistic eaters
with a varied diet. Unfortunately, they are a major predator of sea turtle eggs
and hatchlings.

There are over 10,000 species of Polychaetes or “bristle” worms. Bristles
cover its snake-like body which averages 4 inches in length. Some can be
brightly colored, even luminescent. They live in tubes which can often be
seen at low tide.