Before you reach
living reefs on
an intertidal area, there is often a
stretch of shore where there are more dead than living corals. An
area with such coral rubble may appear rather dead but is actually
full of life if you take a closer look.
Dead corals provide a place for animals to cling to, and hiding places
in crevices and nooks and crannies. Because such coral rubble areas
tend to be found below the low water mark and are only exposed at
low spring tides, more delicate animals may
be found here.
Where are the animals? Many coral
rubble dwellers are well camouflaged. Some are only active at high
tide. At low tide, these clamp up in their shells or hide in a cool,
moist spot. Others that are active at low tide are usually seen only
when it is dark, or on a cool, overcast day.
Home on the Rubble: Coral rubble
provide a firm surface for lots of animals. An undisturbed coral rubble
area may have spectacular growths of sponges,
The natural holes and channels in dead coral provide a great home
for many small animals. The underside of coral rubble provides shelter
for a vast variety of animals from tiny snails, flatworms,
to larger crabs and fishes and octopuses.
Larger sea anemones and placid sea cucumbers as well as chunky sea
stars may also hide under rubble.
Don't roll the rubble: Because
coral rubble is usually so encrusted with life, it is best not to
turn rubble over to look underneath. Besides which, a poisonous (and
frightened) animal may be hiding there, and both you and the animal
may come to harm.
Not just dead corals: In between
the coral rubble, there may be large living soft corals as well as
smaller living hard corals.
can we explore coral rubble areas in Singapore? Labrador
has the last large mainland coral rubble area. Among our northern
islands, there is a small stretch at Chek
Ubin. Also at Pulau Sekudu. Almost all our Southern
islands have coral rubble areas with a vast stretch at Pulau
Semakau, as well as some at Kusu
Natural coral rubble area at Pulau Semakau.
Sponges encrust coral rubble at Chek Jawa.