Coral growth rate: Variation with depth

Abstract Light and temperature are two of the most important physical factors affecting rates of growth of reef corals. The effect of light has been determined by X-radiographic measurement of long-term growth rates for 89 colonies of the coral Montastrea annularis collected over a 27.5-m depth range from St. Croix, U.S. Virgin Islands. These measurements, in conjunction with measurements of skeletal density, have established that M. annularis calcifies most rapidly at intermediate depths, and they have confirmed the identification of two distinct populations within this important frame-building species.