Ecological Biochemistry of Corals
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groups, connecting separate molecules of polymer. The number of these
sulfo-groups in the mucus controls its viscosity and the process of its
denaturation (Richards et al. 1983).
The mucus excreted by scleractinian corals is a significant source of food
for many reef fish and invertebrates. On the mucus feed numerous infaunal
animals and commensals of corals - crabs, shrimp, flat worms, ciliates
(Patton 1976; Castro 1976; Bruce 1976) and some specialized fish as well
(Benson and Muscatine 1977; Benson et al. 1978). The organic flakes and
aggregates formed from mucus which is shed by corals are quickly
overgrown with bacteria, thus increasing their food quality. At this stage
these aggregates are readily consumed by zooplankton and by sessile
animals (Sumner et al. 1975; Coffroth 1984). Mucus that settles on the
bottom is one of the main sources of feeding for reef fauna, comprising a
significant part of the organic matter in reef bottom sediments (Daumas and
Thomassin 1977).