Table of Contents

• Coverage
• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Supplemental Files
• Related Publications
• Related Datasets
• Parameters
• Instruments
• Project Information
• Program Information
• Funding

Coral community calcification (G, kg CaCO₃ m^-2 yr^-1) by site and year was calculated based on colony sizes that were measured as described above and used to calculate G summed by photoquadrat (i.e., photoquadrats were treated as statistical replicates). In the formulation applied herein, G provides an estimate of gross coral calcification, as we do not consider any source of dissolution and bioerosion. G is not equivalent to NCC because dissolution/bioerosion is not considered, and we do not evaluate calcification by taxa other than corals. First, the mean diameters of each coral colony in each quadrat (i.e., the mean colony diameter in planar view), were used to estimate the 3-dimensional colony size (i.e., the actual size of living tissue) based on taxon-specific rugosity for Caribbean corals (Equation 1, see supplemental file "Coral Calcification Equations"). Actual tissue cover was required to accurately estimate colony-level calcification, because coral species differ in their 3-D shapes, which affects G depending on colony morphology.

See Equations in supplemental pdf file "Coral Calcification Equations".

The annual calcification (kg colony-1 yr-1) of corals in each photoquadrat was calculated by summing the CPi values by taxon. Values were standardized to a square meter to be consistent with a commonly used unit of G, kg CaCO3 m-2 yr-1, which can be converted to other units through stoichiometry (e.g., 1 kg CaCO3 m-2 yr-1 = 27.4 mmol CaCO3 m-2 d-1). In our calculations we assume that coral calcification rates are uniform with colony size (i.e., isometric). Work in Moorea has shown that some colony calcification rates increase rapidly up until colonies are ~10–15 cm diameter, but our assumption of isometry is currently necessary for Caribbean corals as the data necessary to parameterize the relationship between colony size and coral calcification currently is lacking for the corals in this region. However, given that nearly all colonies in our study are small (averaging < 6 cm) and remain small due to high demographic turnover, the use of taxon-specific calcification (i.e., independent of colony size) rate is less problematic than would be the case in Moorea. Our assumption of isometric coral calcification may render a conservative bias in our calculations of coral G. Using photoquadrats as statistical replicates, coral G (pooled among taxa) was compared among sites and years (Hypothesis 2) using a mixed effects, two way ANOVA in which site was a random effect, year was a fixed effect, and G was log(x +1) transformed to meet the assumptions of the statistical test. G was also averaged by site and year using values pooled among taxa and also by taxon, and the values were qualitatively compared over time for each site. They were also used to assess whether the taxa contributing to coral G varied within- or among- sites as a function of coral community composition and colony size.

Location: South coast of St. John, US Virgin Islands. 18.31644, -64.724528. Research conducted during annual field expeditions to research lab: The Virgin Islands Ecological Research Station.

ReefBudget software to calculate G (Perry and Lange, 2019).

BCO-DMO Data Manager Processing notes:
* Sheet 1 from "Coral_G_1992_2019.xlsx" excel file imported into the BCO-DMO data system.
* Column names changed to conform with BCO-DMO naming conventions (only A-Za-z0-9 and underscores used).
* Supplemental site list imported and lat lon converted from degrees decimal minutes to decimal degrees and rounded to 5 decimal places.
* lat and lon columns added by using the site name as a key to join to the site list.
* Taxonomic names matched using the World Register of Marine Species Taxa match tool on 2023-06-30.  Added supplemental file with associated LSIDs (see "Taxonomic Identifiers).

Long Term Research in Environmental Biology (LTREB) in US Virgin Islands:

From the NSF award abstract:
In an era of growing human pressures on natural resources, there is a critical need to understand how major ecosystems will respond, the extent to which resource management can lessen the implications of these responses, and the likely state of these ecosystems in the future. Time-series analyses of community structure provide a vital tool in meeting these needs and promise a profound understanding of community change. This study focuses on coral reef ecosystems; an existing time-series analysis of the coral community structure on the reefs of St. John, US Virgin Islands, will be expanded to 27 years of continuous data in annual increments. Expansion of the core time-series data will be used to address five questions: (1) To what extent is the ecology at a small spatial scale (1-2 km) representative of regional scale events (10's of km)? (2) What are the effects of declining coral cover in modifying the genetic population structure of the coral host and its algal symbionts? (3) What are the roles of pre- versus post-settlement events in determining the population dynamics of small corals? (4) What role do physical forcing agents (other than temperature) play in driving the population dynamics of juvenile corals? and (5) How are populations of other, non-coral invertebrates responding to decadal-scale declines in coral cover? Ecological methods identical to those used over the last two decades will be supplemented by molecular genetic tools to understand the extent to which declining coral cover is affecting the genetic diversity of the corals remaining. An information management program will be implemented to create broad access by the scientific community to the entire data set.

The importance of this study lies in the extreme longevity of the data describing coral reefs in a unique ecological context, and the immense potential that these data possess for understanding both the patterns of comprehensive community change (i.e., involving corals, other invertebrates, and genetic diversity), and the processes driving them. Importantly, as this project is closely integrated with resource management within the VI National Park, as well as larger efforts to study coral reefs in the US through the NSF Moorea Coral Reef LTER, it has a strong potential to have scientific and management implications that extend further than the location of the study.

Coral reefs have long been recognized for their diversity, and unique functional roles, but these features have been undermined by decades of disturbances that cast doubt on their ability to survive. Against this backdrop, 2017 brought two hurricanes of unprecedented magnitude to the Caribbean, both of which damaged coral reefs that already were degraded compared to those of a few decades ago. While the impacts of these storms on some of the few coral reefs protected within the US National Park and National Monument systems is particularly unfortunate, it also creates unique opportunities to understand the impacts on coral reefs that have been studied in detail for decades. This project builds on these opportunities by leveraging 31 years of coral reef monitoring research, much of which has been supported by NSF, to describe the impacts of Hurricanes Irma and Maria on coral reefs in St. John, US Virgin Islands. That the analyses will reveal severe destruction is a forgone conclusion, but what remains unknown is how present-day reefs will respond to severe versions of a well-known disturbance (hurricanes), and how these effects will impact their long-term survival. Post-storm surveys and new analyses will be used to determine whether ongoing declines in coral abundance have influenced the way coral reefs respond to storms, notably to enhance post-storm mortality, and reduce the capacity to recover from such event. To achieve these outcomes, a team of researchers from California State University, Northridge, will use a cruise on the R/V Walton Smith to survey the reefs of St. John using photography and in-water counts to generate data that will be analyzed throughout 2018. The benefits of this research will extend beyond scientific discoveries to include leveraged support for other scientists participating in the cruise, evaluation of the status of natural resources in the VI National Park, the delivery of relief supplies from Miami to St. John, and the creation of unique research and training opportunities for graduate students who will participate in all phases of the project.

Coral reefs have undergone dramatic changes in community structure since they were first described in the 1950's, and the current onslaught of threats from rising temperature, declining seawater pH, storms, and numerous other events has cast doubt on their persistence in the Athropocene. With such profound changes underway, time-series analyses of community structure are on the cutting edge of contemporary studies of coral reefs. In the Caribbean, the impact of two category 5 hurricanes underscores why time-series are important, as they are the only means to describe the impact of such events, and critically, create the context for testing hypotheses regarding impacts and consequences of disturbances. This project addresses the impacts of Hurricanes Irma and Maria on the coral reefs of St. John, US Virgin Islands, which have been studied since the 1950's, and for the last 31 years largely with NSF LTREB support. This support provides descriptions of the population dynamics of the important coral, Orbicella annularis, and the coral community dynamics in adjacent habitats. Any study of the effects of these storms will demonstrate that large waves kill corals, but here intellectual merit is acquired through testing of general hypotheses: (1) storm impacts on O. annularis will be colony-density dependent, (2) delayed coral mortality will be accentuated compared to previous storms, (3) the resilience of coral communities to physical disturbances has declined since 1989, and (4) evolutionary rescue will mediate reef recovery for select corals through large initial population sizes, density-dependent population growth, and recruitment. These hypotheses will be tested using a 14 day cruise on the R/V Walton Smith to collect critical time-sensitive data, followed by a year of analysis of new and legacy photographic data.

Describing how ecosystems like coral reefs are changing is at the forefront of efforts to evaluate the biological consequences of global climate change and ocean acidification. Coral reefs have become the poster child of these efforts. Amid concern that they could become ecologically extinct within a century, describing what has been lost, what is left, and what is at risk, is of paramount importance. This project exploits an unrivalled legacy of information beginning in 1987 to evaluate the form in which reefs will persist, and the extent to which they will be able to resist further onslaughts of environmental challenges. This long-term project continues a 27-year study of Caribbean coral reefs. The diverse data collected will allow the investigators to determine the roles of local and global disturbances in reef degradation. The data will also reveal the structure and function of reefs in a future with more human disturbances, when corals may no longer dominate tropical reefs.

The broad societal impacts of this project include advancing understanding of an ecosystem that has long been held emblematic of the beauty, diversity, and delicacy of the biological world. Proposed research will expose new generations of undergraduate and graduate students to natural history and the quantitative assessment of the ways in which our planet is changing. This training will lead to a more profound understanding of contemporary ecology at the same time that it promotes excellence in STEM careers and supports technology infrastructure in the United States. Partnerships will be established between universities and high schools to bring university faculty and students in contact with k-12 educators and their students, allow teachers to carry out research in inspiring coral reef locations, and motivate children to pursue STEM careers. Open access to decades of legacy data will stimulate further research and teaching.

This project has been supported by continuing grants:
OCE-2019992 "RUI: Pattern and process in four decades of change on Caribbean reefs"  (2020-2026)
OCE-2546549 "RUI Pattern and process in five decades of change on Caribbean reefs" (2026-2029)

NSF award OCE-2546549 project summary:

Overview

This proposal focuses on American coral reefs in the United States Virgin Islands, most of which are trending towards persistent low coral colony abundances. This is a conspicuous aspect of the coral reef crisis, and while much is known of the disturbances causing corals to die, little is known about the ecological implications of low coral abundance. This project leverages four decades of research in St. John by using multiple sites to test five hypotheses addressing mechanisms preventing depleted coral populations from increasing in size, and they are developed in a hierarchical framework to advance basic ecology, and enhance understanding of coral reefs and the ecological processes structuring marine communities in the Anthropocene. The project is mensurative because it is conducted in an MPA, but its scope is broadened through: (a) analyses of algal symbionts (Symbiodiniaceae) with co PI, Cunning (Shedd Aquarium), (b) by extending the coral reef time-series from 40 to 43 yrs, and (c) applying wavelet analyses to the time-series. Three years of funding will support 1 mo/y of fieldwork, 11 mo/y of analysis, QA/QC, graduate training, a one year postdoc, outreach, and manuscript preparation. This RUI proposal is targeting the OCE call NSF PD 23-1650.

Intellectual merit

The intellectual merits lie in the hypotheses focused on the mechanisms leading to persistent low abundance coral communities. This project is designed around a conceptual model that preserves the integrity of a 43 yr time series and tests 5 integrated hypotheses addressing four science needs: (1) advancing basic ecology, (2) leveraging of existing data to realize emergent properties, (3) serving data to end users, and (4) outreach benefitting American stake holders. Over three years, fieldwork and analyses will address: H₁ Coral reef community structure is converging to a stable low coral abundance state; H₂. The impact of disturbances is mediated by the spatial structuring of community dynamics, and the expression of portfolio effects; H₃ Intensification of the coral recruitment ‘bottleneck’ and its gradual transition to settlement failure; H₄ Declining populations sizes of echinoids limit the formation of grazing halos in which corals settle; H₅ Persistence of low abundance coral communities is favored by changes in the symbiodiniacaea complement.

Broader impacts

This project will advance discoverability of time-series data in the public domain, student mentoring and experiential fieldwork, research on the causes of changes affecting marine communities, and in-person outreach at schools in California an Illinois, the University of the Virgin Islands, and the Friends of the VI National Park. Open access to high resolution data quantifying coral reefs over five decades is a critical community need to which this project will respond by placing in > 14,000 photoquadrats in the public domain (1987-present). Up to five graduate (MS) students will be mentored in marine science through fieldwork and lab analysis, and one REU students will be supported in a graduate mentoring framework. At middle schools, an “aquarium library” program will place marine animals in classrooms for 2–3 weeks in collaboration with the non-profit organization, ‘Underwater Zoo’. At high schools, ‘marine biology clubs’ will address project themes, provide research opportunities, and entrain teachers in field trips. In the field, teachers will conduct research leading to publications and will lead outreach activities with children in the junior ranger program administered by the Friends of the VI National Park. The efficacy of outreach tasks will be assessed through pre/post surveys and questionnaires administered using Google forms by teachers at partner schools. The results of assessment will be used to tune project deliverable to better meet the needs of the outreach audience.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

Related Projects:

• Affiliated with MCR-LTER - https://www.bco-dmo.org/project/2222
• Serves as a new project that builds on NSF DEB-1350146 - RUI-LTREB Renewal: Three decades of coral reef community dynamics in St. John, USVI: 2014-2019 - https://www.bco-dmo.org/project/734983
• Overlaps with OCE 17-56678 (which focuses on soft corals with H. Lasker) - Collaborative Research: Pattern and process in the abundance and recruitment of Caribbean octocorals - https://www.bco-dmo.org/project/752508
• LTREB Long-term coral reef community dynamics in St. John, USVI: 1987-2019 - https://www.bco-dmo.org/project/2272
• RUI: Pattern and process in four decades of change on Caribbean reefs - https://www.bco-dmo.org/project/835192
• RAPID: Hurricane Irma: Effects of repeated severe storms on shallow Caribbean reefs and their changing ecological resilience - https://www.bco-dmo.org/project/722163

Long Term Research in Environmental Biology (LTREB)

Supports research for a period of 10 years or longer to generate an extended time series of data with a focus on evolutionary biology, ecology and ecosystem science.

Synopsis
The Long Term Research in Environmental Biology (LTREB) Program supports the generation of extended time series of data to address important questions in evolutionary biology, ecology, and ecosystem science. Research areas include, but are not limited to, the effects of natural selection or other evolutionary processes on populations, communities, or ecosystems; the effects of interspecific interactions that vary over time and space; population or community dynamics for organisms that have extended life spans and long turnover times; feedbacks between ecological and evolutionary processes; pools of materials such as nutrients in soils that turn over at intermediate to longer time scales; and external forcing functions such as climatic cycles that operate over long return intervals.

Long Term Research in Environmental Biology (LTREB)

Supports research for a period of 10 years or longer to generate an extended time series of data with a focus on evolutionary biology, ecology and ecosystem science.

Synopsis
The Long Term Research in Environmental Biology (LTREB) Program supports the generation of extended time series of data to address important questions in evolutionary biology, ecology, and ecosystem science. Research areas include, but are not limited to, the effects of natural selection or other evolutionary processes on populations, communities, or ecosystems; the effects of interspecific interactions that vary over time and space; population or community dynamics for organisms that have extended life spans and long turnover times; feedbacks between ecological and evolutionary processes; pools of materials such as nutrients in soils that turn over at intermediate to longer time scales; and external forcing functions such as climatic cycles that operate over long return intervals.