Resilience assessment of Puerto Rico’s coral reefs to inform reef management
Gibbs, D. AND J. West. Resilience assessment of Puerto Rico’s coral reefs to inform reef management. PLOS ONE . Public Library of Science, San Francisco, CA, 14(11):e0224360, (2019). https://doi.org/10.1371/journal.pone.0224360
This article reflects a project led by David Gibbs during his ORISE Fellowship, in support of ACE 039 Adaptation Planning Frameworks. This assessment is a proof of concept for the ability to use publicly-available monitoring data to apply resilience indicators to assess relative resilience (which is characterized by the sensitivity and adaptive capacity components of vulnerability) of reefs in a region--in this case, the island of Puerto Rico. While being informative to managers in its own right, this information also feeds into tools such as the Adaptation Design Tool, to inform management adjustments to account for system vulnerabilities to ongoing environmental changes.
Globally increasing sea surface temperatures threaten coral reefs, both directly and through interactions with local stressors. More resilient reefs have a higher likelihood of returning to a coral-dominated state following a disturbance, such as a mass bleaching event. To advance practical approaches to reef resilience assessments and aid resilience-based management of coral reefs, we conducted a resilience assessment for Puerto Rico’s coral reefs, modified from methods used in other U.S. jurisdictions. We calculated relative resilience scores for 103 sites from an existing commonwealth-wide survey using eight resilience indicators—such as coral diversity, macroalgae percent cover, and herbivorous fish biomass—and assessed which indicators most drove resilience. We found that sites of very different relative resilience were generally highly spatially intermixed, underscoring the importance and necessity of decision making and management at fine scales. In combination with information on levels of two localized stressors (fishing pressure and pollution exposure), we used the resilience indicators to assess which of seven potential management actions could be used at each site to maintain or improve resilience. Fishery management was the management action that applied to the most sites. Furthermore, we combined sites’ resilience scores with projected ocean warming to assign sites to vulnerability categories. Island-wide or community-level managers can use the actions and vulnerability information as a starting point for resilience-based management of their reefs. This assessment differs from many previous ones because we tested how much information could be yielded by a “desktop” assessment using freely-available, existing data rather than from a customized, resilience-focused field survey. The available data still permitted analyses comparable to previous assessments, demonstrating that desktop resilience assessments can substitute for assessments with field components under some circumstances.