Restoring Coral Reefs: An Examination of Methodologies in Use Worldwide

73 pages. Presented to the Department of Marine Biology and the Robert D. Clark Honors College in partial fulfillment of the requirements for the degree of Bachelor of Science June 2018Abstract – Corals reefs are one of the most biodiverse ecosystems on the planet and they provide vitally important habitat for a host of marine species. They also provide humans with many goods and services. These ecosystems are in rapid decline worldwide due to the combined effects of many anthropogenic stressors ranging from global climate change to more local factors like pollution and overfishing. In response, methods of active reef restoration by direct human intervention began to appear, and over the past three decades the field of reef restoration has grown rapidly to include a wide variety of methods and dozens of species of corals. While restoration is now generally accepted as a viable means of restoring the biodiversity and ecosystem function of coral reefs, it is a relatively new field that is still developing. Many restoration efforts are not set up in ways that are conducive to being written up as formal studies. Consequently, they typically lack rigor and critical evaluation of their effectiveness which hinders attempts to critically compare the efficacy of various methods. Several reviews and meta-analyses of reef restoration methodologies have already been conducted, yet most of these studies do not directly compare quantitative and qualitative data of methods and the results those methods produce. This thesis assesses the breadth of restoration methods in use and compares them in terms of how they affect survival of corals. My thesis also includes qualitative information on other factors that influence the success of restoration efforts. I used both graphical and statistical methods to analyze survivorship data. Data on growth were not amenable to quantitative analysis due to the disparity of growth metrics. My investigation provides substantial evidence for the need to tailor restoration methods to the species. I also identify several shortcomings in how restoration studies report their data and I use these findings to propose necessary components of a standardized framework for reporting. Standardization will allow future meta-analyses of reef restoration to assess what methods are likely to produce the highest success rate for a given restoration site and species. Standardization of reporting is critical to the future of the field so that techniques may be improved, thereby maximizing the impact that restoration efforts make toward rehabilitating the biodiversity and ecosystem function of a degraded reef ecosystem