Featured Archive - 2021 Publications

Below is a sampling of publications generated by NOAA's coral ecosystem activities in 2021. To access a complete list of NOAA coral ecosystem related publications, use the CoRIS Geoportal
( search tool.

Predicting extreme tide events to inform shallow reef community restoration and management in Guam

This project report describes a novel approach to develop a spatially explicit model to predict the frequency of low-stand events. This will help guide the selection of restoration sites, and identify both sites at future risk and those with greater refuge from low-stand events that could benefit from increased management. Benthic surveys to evaluate mortality were undertaken at 18 sites around Guam that experienced significant coral mortality from recent extreme low-tide events or were strategically selected for geographic representation around the island. At these sites, tidal variations were logged over five-week periods, and critical depth thresholds (e.g., past subaerial exposure) were determined. The tidal data from the sites were correlated with long-term data from the Apra Harbor tide gauge on Guam. Using the derived relationships and depth thresholds, and modifying a model used to predict high-tide (or nuisance) events, spatially-explicit predictions of vulnerability to subaerial exposure were produced (see map). This analysis has demonstrated the applicability of the methodology to other sites in the Pacific region, such as American Samoa and the Saipan Lagoon in CNMI, each of which has experienced similar, significant, recent coral loss.