Environmental Effects on the Morphology of Hawaiian Rice Coral (Montipora capitata)

Abstract

Hawaiian scleractinian corals provide diverse ecosystems that are extremely sensitive to environmental changes. O`ahu experiences rapid environmental alteration due to its human population, thus offering an ideal test region for this study. Here, the focus is identifying the relationship between the morphology of Montipora capitata corals and the environmental factors of sedimentation, effluent, sea surface temperature (SST), wave action, irradiance (PAR), and depth using a multiple logistic regression model and a generalized linear model (GLM). Environmental factor values were derived from the 2018 Ocean Tipping Points Hawai`i Study (OTP) and correlated with data from 198 coral colonies, which were collected via a comprehensive sampling campaign at 97 locations. Statistical analyses found significant relationships between M. capitata morphology and SST, sedimentation, wave action, and depth. Additionally, a visual representation of coral morphology around O`ahu provides direct insight on the prevalence of different coral growth patterns while supporting the findings of the GLM. These findings present the first documentation of this species’ growth island-wide, facilitating a broader understanding of Hawaiian Montipora corals and the crucial factors influencing their growth. Such insights are instrumental in advancing conservation initiatives aimed at mitigating the adverse effects of both natural phenomena and human-induced climate change.