In situ Temperature Profile of Shallow Reef Communities in Negros and Apo Island: 2013-2014

Abstract

Coral reefs provide a wide variety of ecosystem services and goods that benefit humankind. However, the survival and health of reefs are threatened by natural and anthropogenic factors such as climate change and pollution. Increased seawater temperature often results in bleaching of certain coral species. This study aimed at profiling in situ temperature of shallow reef communities in Apo I. and Sibulan, Negros I. using data loggers programmed to record hourly. Results for Apo showed temperature peaked in the months of May, June, and July. For Sibulan site, peaks were observed in May, June, and September. The lowest temperature for both sites was observed in February. Comparison with satellite-derived sea surface temperatures (SST) for the Bohol Sea
indicated Apo Island recorded lower temperatures (>0.5°C) except for the months of October, November, and December whereas in Sibulan site, logger-derived temperature recordings were mostly higher by <0.5 °C in the months of March, May, October, November, December, and February. Between sites, variation may be explained by differences in coastal profiles, depths of reefs, and influences of different water current systems. Variation from satellite-derived data may be due to depth differences since the latter were taken only from the surface. Continuous in situ temperature monitoring is recommended to provide a more localized profile especially in this period of changing climate.