Correlation of chlorophyll a and total carotenoid concentrations with coral bleaching from locations on the Pacific coast of Mexico

Abstract

Diving campaigns were undertaken to study the bleaching phenomenon in the Mexican Central Pacific and to catalogue the degree to which bleaching affected three coralline reefs (la Boquita, Carrizales, and Tenacatita). Bleaching evaluations of Pocillopora capitata were conducted by assessing the concentrations of chlorophyll a and total carotenoids from samples along submarine transect lines. We identified that the Reffs Boquita and Tenacatita locations were predominantly composed of bleached and pale coral populations. The concentrations of chlorophyll a within the areas of the different populations were greater at sites of greater depth compared with those at the surface. In contrast, the total carotenoid concentrations in normal pigmented coral at greater depth were significantly higher (P < 0.05) compared with both levels of discolouration at both depths. The chlorophyll a/total carotenoid ratios in these populations are discussed as a potential mechanism responsible for the poor condition of these corals as a result of environmental stress.

Keywords:

• Carotenoids
• chlorophyll a
• coral
• bleaching

Acknowledgments

This project was supported by the Alvarez-Buylla de Aldana Foundation, University of Colima. We are also grateful to the editor Dr. Scott Butler (Managing Editor, English Manager Science Editing) for reviewing the language.