Award: OCE-1332915

This project focused on soft corals in St. John, US Virgin Islands, which provides some of the most extensively studied reefs in the US. One such study began in 1987 to document long-term changes affecting stony corals, and in an era of intense environmental challenges, this project described a decadal-scale history of stony coral mortality. Like most studies of "coral" reefs, the legacy project focused on stony corals and largely overlooked soft corals. The present award was a collaboration between California State University, Northridge (Dr. P.J. Edmunds), and the University of Buffalo (Dr. H.R. Lasker) and had the objective of addressing this omission through a soft coral "overlay" to the existing analysis of stony corals. The study was based in St. John, which provides a unique location to study coral reefs because ~ 75% of the island is protected within the VI National Park. Therefore, changes on the reefs are less likely to reflect local disturbances, and instead, reflect broader-scale phenomena such as gradually changing climatic conditions. To exploit the opportunity created by St. John, this project was implemented in four phases: (1) description of the species of soft corals on the shallow reefs, (2) analyses of the trends in soft coral abundance over the past 25 y, (3) identification of mechanisms causing soft corals to change in abundance, and (4) developing the capacity to forecast the future of soft corals on Caribbean reefs. Through a three-year program of field-based research, we have made strong progress in all four phases, and now are poised to expand the study into the next decade. The most important discovery arising from this work provides evidence that soft corals have thrived on these reefs over the last 25 years, and it is likely that they will do so into the future. Since 1987, stony corals have died at an alarming rate, but in their place, dense "forests" of soft corals have grown. "Forest" is a perfect analogy to describe these communities, as most Caribbean soft corals grow upward into the water column, thereby escaping competition with algae on the seafloor. The canopy of this forest creates local conditions promoting resilience (i.e., regrowth following damage) through enhanced recruitment. Soft coral recruits settle in profusion beneath the canopy, where they grow in cracks, from which they quickly extend upwards. Their colonies can grow at such high densities that their branches interfere with adjacent colonies, and promote self-thinning much as occurs among trees in a dense forest. Our work provides compelling evidence that octocorals have become more abundant over the last few decades, both in the Caribbean and within St. John. Interestingly, these communities do not appear to be "new" per se, rather present-day soft coral communities reflect a spatial expansion of the communities described decades ago. Forests of soft corals provide an impressive sight to the casual observer, and while they allow reefs to maintain cover and shelter fish, the soft colonies cannot provide the structural protections to near-shore habitats that traditionally have been provided by stony corals. This project was conducted during a period of remarkable calm (2014-2017) in terms of hurricanes impacting St. John, but Hurricane Irma has provided a dramatic end to this period. The next few years will reveal whether soft corals really are more resilient to catastrophic disturbances than stony corals. This research was conducted through a program of broader outreach providing unique opportunities for training promoting science literacy and science careers. These opportunities were provided to participants at multiple levels of scientific training, and the majority included travel to St. John to obtain hands-on experience in field ecology, and marine natural history. The project employed two postdoctoral scholars to advance operations at CSUN and in St. John, and their work was supported through graduate students opportunities that included students who were studying for their MS degrees on soft coral biology. Undergraduates also participated in the fieldwork, where they served critical roles in advancing basic field science while conducting independent research furthering their scientific interests. A key part of the project has been engagement with schools, teachers, and children in California and the Virgin Islands. Faculty and graduate students have worked with teachers in California to maintain "marine biology" clubs providing exposure to marine research, the goals of this project, and research opportunities. These efforts have been advanced through teacher involvement, with personal participating in fieldwork in St. John where they conducted research and led outreach activities. The host of our research in St. John - the Virgin Islands Environmental Resource Station – supports a summer program for local children, and this provided the opportunity for science presentations and field activities focused on the time-series analyses at the heart of this project. Data from this project are available at http://www.bco-dmo.org/project/562086 and http://coralreefs.csun.edu. Last Modified: 09/09/2017 Submitted by: Peter J Edmunds