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Damselfish as keystone species in reverse: intermediate disturbance and diversity of reef algae
Science (New York, N.Y.)
|April 29, 1983
Abstract:
Substrates located within the defended territories of Hawaiian damselfish for 1 year were subjected to intermediate grazing intensity and, as a result, showed greater diversity of algae than substrates either protected within fish-exclusion cages or exposed to intense fish grazing outside territories. Thus, this damselfish enhances local diversity on reefs through "intermediate-disturbance" effects, and is a keystone species that decreases rather than increases overall predation intensity relative to areas where it is absent.
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