Recruitment of Porites (Scleractinia) on artificial substrate in reefs affected by the 1997–98 El Niño in Banderas Bay, Mexican Pacific

Abstract

Mexican Pacific coral reefs were severely damaged by the sea surface warming observed during the 1997–98 El Niño. In Banderas Bay, massive coral mortality was as high as 97%, and the surviving colonies were exposed to sublethal temperatures and thermal stress. In this coral recruitment study we attempted to estimate the recovery and potential repopulation of corals in the Mexican Pacific. After the El Niño event, we used terracotta tiles to monitor the settlement of coral larval propagules at nine reefs in the region. The recruitment study took place from December 1998 to July 1999. Settlements of nine specimens of Porites were recorded at two localities. This is the first settlement record for this coral genus in the eastern tropical Pacific and the one with the largest number of specimens recruited during a study involving artificial substrate. The results indicate that these reefs do not totally depend on the arrival of allocthonous coral propagules from other regions of the tropical Pacific to maintain their development. This study also shows that corals maintain their reproductive activity despite the environmental disturbances. Therefore, sexual reproduction of reef corals of this region provides an effective alternative for the recovery of Mexican Pacific coral reefs.

Keywords

• coral recruitment
• Porites
• artificial substrate
• Mexican Pacific reefs
• El Niño