KOROR STATE GOVERNMENT MARINE TOUR GUIDE ... - C3

3.8 Important Marine Life
3.8.1 Marine Algae
The plants of the reef are often not very obvious as they lack roots, stems, leaves and
even the green color of terrestrial plants. They can be brown, red or green.
Role of the Reef
As in most ecosystems, plants form the basis of the reef’s food chain. Many species of
marine algae contribute greatly to the overall structure of the reef. Coralline algae act as
the reef’s mortar; by secreting limestone, like corals and by growing between coral
fragments and rubble, algae helps bind the reef together. Limestone-producing algae
also make up a major component of the sand.
3.8.2 Sponges
Halimeda – is a green algae that produces calcium carbonate or
limestone. The remains of the disc-shaped ‘leaves’ are responsible for
over 50% of the coral sand found in many parts of the reef! Halimeda
can produce limestone very quickly, doubling its weight in as little as
two weeks. It has been estimated that Halimeda flakes are capable of
producing 13cm of reef in less than 1000 years. The brown surface
on the reef flat is actually a thin layer of rapidly growing algal turf. This
is a primary food source for many of the reefs herbivores like
parrotfish, surgeonfish and damselfish, which can be seen feeding in
the shallows. If it wasn’t for their constant grazing; this algae would
quickly grow to form a fuzzy algal layer.
Pat Colin
What are sponges?
Sponges are animals that filter water volumes equivalent its own body volume every 4-
20 seconds. From giant vase-like structures to obscure creeping forms covering rocks,
sponges are important for more than just washing the car!
Their characteristics include:
Body covered with tiny openings called pores
Food particles are filtered from water
Skeletal structure consists of limestone or silica spines called spicules
Great range of colors and shapes
Attached to the sea floor
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