Some aspects of the population biology of the reef coral, Pocillopora damicornis (Linnaeus), in Taklong Island, Guimaras

Abstract

Demographic parameters that included growth rate, reproduction, recruitment and mortality ofthe branching reef coral, Pocillopora damicornis Linneaus, in Kalirohan reefflat, Taklong Island, Guimaras were investigated from 1991 to 1992. Radial colony growth averaged 20 mm per year regardless of initial size. Planulation was the predominant mode of reproduction. This occurred monthly throughout the year with peak larvae release between the new moon and first quarter. There was regular recruitment event of larval origin that corroborated monthly spawning. Size class specific mortality rates did not vary much but the largest size cohort had the least. Net larvae-derived recruitmentsurpassed depletion rate (natural mortality) of established colonies at the end of the study period. The observed demographic rates resulted in increased population size where more than half are recruits and maintained the left-skewed population size structure.