USGS Pacific Coral Reefs Website

Monitoring Coral Reefs

Scuba and snorkel dives allow scientists to directly identify coral species and make estimates of living coral coverage and biodiversity. Underwater photography and video transects made by divers provide a record that can be used to monitor subtle changes in the reef ecosystem. Our scientific partners from the University of Hawai‘i, Coral Reef Assessment and Monitoring Program (CRAMP) survey Hawai‘i's reefs annually.

CRAMP divers survey Moloka‘i's coral reefs with video transects and underwater photography. (photos courtesy of the University of Hawai‘i)

A precisely positioned PVC framer guarantees that the same colonies of coral are being photographed on an annual basis, allowing for the assessment of changes over time. (photo courtesy of the University of Hawai‘i)

The USGS is using many different monitoring techniques in addition to the CRAMP survey results in order to characterize the dynamics of Pacific coral reefs. On Moloka‘i, digital cameras are stationed both above and below water to capture sedimentation events. A timer allows a snapshot image to be taken several times each day. Sediment traps are used to measure patterns of accumulation. Oceanographic instruments measure waves and current patterns, and suspended sediment in the water column.

Many different monitoring techniques are used to characterize coral reef dynamics. (click on image to see larger version 41K)

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