Experimental Manipulations of a Solitary Coral (Fungia, Scleractinia) with Emphasis on the Effects of Light

The metabolic rate per unit area of the solitary scleractinian coral Fungia (Danafungia) horrida did not vary significantly within a size range of 5–14 cm (diameter). Likewise, maintenance time in the laboratory up to a period of 1 week did not appear to influence metabolic performance. Gross photosynthetic rates, when measured under similar light intensities, did not differ significantly between corals in the field and in the laboratory. Significant variations in photosynthetic response to light occurred. Combined data for this and other species of the genus Fungia from the same reef flat were used to generate light response curves which showed I _k, to be about 800 microEinsteins m⁻² s⁻¹, as determined from the hyperbolic tangent formulation. Theoretical maximum gross primary production was about 250 μg O₂ cm⁻² h⁻¹.