EFFECT OF EPIBIONTS ON THE MICRODISTRIBUTION OF CHLOROPHYLL IN CORALSAND ITS DETECTION BY FLUORESCENCE SPECTRAL IMAGING

The spatial distribution of chlorophyll in three coral species carryin g invertebrate symbionts was determined using spectral imaging techniq ues. From each pixel of the image, full fluorescence spectral data was obtained as well as comparative ratios of fluorescence. The multipixe l fluorescence map and the relative-intensity fluorescence ratios demo nstrated a high concentration of chlorophyll a next to the pits of Cry ptochirus coralliodytes in Favites halicora. Spectral similarity maps of Goniastrea retiformis infested with Lithophaga lessepsiana and of M illeporum dichotoma infested with Savignium milleporum revealed relati vely higher chlorophyll concentrations in these two corals next to the symbionts. We hypothesize that the invertebrate symbionts fertilize t heir immediate surroundings with their excreta, enhancing algal growth . The spectral analysis system used in this study made it possible to distinguish such changes by spatial quantitation of the fluorescence e mitted from small surface areas.