Coral Reproduction
1 During the annual
coral-spawning
events, corals will
release eggs
and sperm, which
meet in the water
column to form
coral gametes2 These gametes
divide and
metamorphose into
free-swimming
coral larvae, which
actively seek a
suitable location
to settle4 The single polyp
will attach itself
firmly to a base
and start secreting
a hard skeleton.
Corals will first
focus their energy
on creating a
solid base, before
starting to branch
or grow upwards(^5) The single polyp
starts to divide,
forming genetically
identical polyps
around the
primary polyp
SEXUAL REPRODUCTION
Spawning
larvae
Fertilization
3 Once the larvae
reach the seafloor,
they will attach to
the substrate and
start developing
into a coral polyp.
When corals look
for a place to settle,
they prefer crevices
and divots, and pink
to white colours
found in corallite
algae. These colours
are the sign of a
healthy reef
Coral Colony
Polyp Divides
Polyp
Skeleton
6 Over time, these
polyps each form
their own hard
skeleton and continue
dividing. Eventually,
hundreds of polyps
will live together
and form a colony,
although some
corals live as a single
polyp reaching
30 centimetres
in diameter
ALL ABOUT CORALS