Page 30 - Coral Reef Teachers Guide

Coral Reef Teacher’s Guide Life on the Coral Reef

Decomposition also plays a role in shaping the over‐ sists of both animals (zooplankton) and plants (phy‐
all reef environment. For instance, when coral dies, toplankton), and some reef animals feed on both while
its limestone skeleton is overgrown by seaweeds and others just feed on animals. For instance, coral polyps
algae, and is invaded by animals, such as worms that and Christmas tree worms extend their tentacles to
bore tubes into its surface. Other animals follow, us‐ catch plankton as it floats by. Like its relative the coral
ing these tubes for their homes. Some species
polyp, the sea anemone, a carnivore, attaches itself to
of sponges also bore into the dead coral by releasing
a piece of limestone rock and extends its poi‐ sonous
chemicals to break down the limestone skeleton into
tentacles to catch the zooplankton and tiny fish that
tiny pieces. These pieces then drift down towards
float by in the ocean current.
the bottom, forming part of the sediment on the reef
floor. The lionfish (Figure 2‐17a) uses camouflage to hide
DID YOU KNOW? itself among the coral and then ambushes unsuspect‐
ing prey as it passes. Some sharks and barracuda use
It has been reported that worms and sponges are speed to chase down their prey. The trumpetfish uses
able to make a dead staghorn coral branch com‐ stealth, hiding behind another fish or within a waving
pletely disappear within one year by boring into its gorgonian coral in order to sneak up on its prey.
surface. The clown triggerfish (Figure 2‐17b) and trunkfish
Predation and Protection catch small crustaceans and fish that hide in the sand

by blowing streams of water out of their mouth to move
METHODS OF PREDATION the sand, or by removing the sand with their fins or
snout.
Many reef animals feed on plankton. Plankton con‐

(a) (b)
Figure 2-17. (a) Lionfish, and (b) clown triggerfish. (Photos: Dean Homayouni)

2‐10