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Caroline Rogers

Publications and source records attributed to Caroline Rogers.

13 recordsLinked to original sources
USGS2024

Pathology of lesions in corals from the US Virgin Islands after emergence of stony coral tissue loss disease

Stony coral tissue loss disease (SCTLD) was first documented in Florida in 2014 and has since spread through the Caribbean causing unprecedented mortality in more than 20 species of corals. The cause of SCTLD is unknown, but bacteria are suspected based on regression of gross lesions in some corals treated with antibiotics. Limited pathology studies on SCTLD exist, but it is likely that ‘SCTLD’ is a general term encompassing tissue loss disease of unexplained origin. Here, we examined pathology of lesions in corals from the US Virgin Islands where SCTLD has recently emerged. The typical histologic lesion of SCTLD in Florida corals was lytic necrosis comprising vacuolation and necrosis of mucus cells with erosion of mesoglea and misshapen endosymbionts with variably sized intracytoplasmic granules and common occurrence of filamentous viral-like particles in endosymbionts visible on electron microscopy (EM). In contrast, USVI corals had mainly lytic mucus cell hypertrophy and necrosis with no involvement of mesoglea, endosymbiont pathology at the light microscopy level was less evident, and VLP were rarely seen on EM. We suspect SCTLD is likely more complex with multiple presentations and potential etiologies depending on geographic region. Further pathological studies from other regions might help refine the case definition of SCTLD.

St. John↗
USGS2023

Framework for facilitating mangrove recovery after hurricanes on Caribbean islands

Mangrove ecosystems in the Caribbean are frequently exposed to hurricanes, leading to structural and regenerative change that elicit calls for recovery action. For those mangroves unaffected by human modifications, recovery can occur naturally. Indeed, observable natural recovery after hurricanes is the genesis of the “disturbance adaptation” classification for mangroves; while structural legacies exist, unaltered stands often regenerate and persist. However, among the >7,000 islands, islets, and cays that make up the Caribbean archipelago, coastal alterations to support development affect mechanisms for regeneration, sediment distribution, tidal water conveyance, and intertidal mangrove transgression, imposing sometimes insurmountable barriers to natural post-hurricane recovery. We use a case study approach to suggest that actions to facilitate recovery of mangroves on Caribbean islands (and similar settings globally) may be more effective when focusing on ameliorating pre-existing anthropogenic stressors. Actions to clean debris, collect mangrove propagules, and plant seedlings are noble endeavors, but can be costly and fall short of achieving recovery goals in isolation without careful consideration of pre-hurricane stress. We update a procedural framework that considers six steps to implementing “Ecological Mangrove Restoration” (EMR), and we apply them specifically to hurricane recovery. If followed, EMR may expedite actions by suggesting immediate damage assessment focused on hydrogeomorphic mangrove type, hydrology, and previous anthropogenic (or natural) influence. Application of EMR may help to improve mangrove recovery success following catastrophic storms, and reduce guesswork, delays, and monetary inefficiencies.

Restoration Ecology↗
USGS2022

A synthesis of coral reef research at Buck Island Reef National Monument and Salt River Bay National Historical Park and Ecological Preserve, St. Croix, U.S. Virgin Islands: 1961 to 2022

This synthesis focuses on the history of research on coral reefs within two U.S. National Park Service units in St. Croix, U.S. Virgin Islands: Buck Island Reef National Monument (from 1961 to 2022) and Salt River Bay National Historical Park and Ecological Preserve (from 1980 to 2022). Buck Island Reef National Monument (BUIS) is off the north shore of the island of St. Croix, in the U.S. Virgin Islands. Established in 1961 and expanded in 2001, it is under the jurisdiction of the National Park Service (NPS). Long-term monitoring programs maintained by the NPS and jointly by the University of the Virgin Islands (UVI) and the Virgin Islands Department of Planning and Natural Resources (VIDPN).

U.S. Virgin Islands, Buck Island Reef National Mon↗
USGS2022

Assessing effects of sediment delivery to coral reefs: A Caribbean watershed perspective

Coral reefs in the western Atlantic and Caribbean are deteriorating primarily from disease outbreaks, increasing seawater temperatures, and stress due to land-based sources of pollutants including sediments associated with land use and dredging. Sediments affect corals in numerous ways including smothering, abrasion, shading, and inhibition of coral recruitment. Sediment delivery resulting in deposition and water quality deterioration can cause degradation at the spatial scale of corals or entire reefs. We still lack rigorous long-term studies of coral cover and community composition before, during and after major sediment stress, and evidence of recovery after watershed management actions. Here we present an overview of the effects of terrestrial sediments on corals and coral reefs, with recent advances in approaches to watershed assessment relevant to the delivery of sediments to these ecosystems. We present case studies of northeastern Caribbean watersheds to illustrate challenges and possible solutions and to draw conclusions about the current state of knowledge of sediment effects on coral reefs. With a better understanding of erosion and the pathways of sediment discharge to nearshore reefs, there is the increased potential for management interventions.

Frontiers in Marine Science↗
USGS2022

A biological condition gradient for Caribbean coral reefs: Part II. Numeric rules using sessile benthic organisms

The Biological Condition Gradient (BCG) is a conceptual model used to describe incremental changes in biological condition along a gradient of increasing anthropogenic stress. As coral reefs collapse globally, scientists and managers are focused on how to sustain the crucial structure and functions, and the benefits that healthy coral reef ecosystems provide for many economies and societies. We developed a numeric (quantitative) BGC model for the coral reefs of Puerto Rico and the US Virgin Islands to transparently facilitate ecologically meaningful management decisions regarding these fragile resources. Here, reef conditions range from natural, undisturbed conditions to severely altered or degraded conditions. Numeric decision rules were developed by an expert panel for scleractinian corals and other benthic assemblages using multiple attributes to apply in shallow-water tropical fore reefs with depths <30 m. The numeric model employed decision rules based on metrics (e.g., % live coral cover, coral species richness, pollution-sensitive coral species, unproductive and sediment substrates, % cover by Orbicella spp.) used to assess coral reef condition. Model confirmation showed the numeric BCG model predicted the panel’s median site ratings for 84% of the sites used to calibrate the model and 89% of independent validation sites. The numeric BCG model is suitable for adaptive management applications and supports bioassessment and criteria development. It is a robust assessment tool that could be used to establish ecosystem condition that would aid resource managers in evaluating and communicating current or changing conditions, protect water and habitat quality in areas of high biological integrity, or develop restoration goals with stakeholders and other public beneficiaries.

Ecological Indicators↗
USGS2022

A biological condition gradient for coral reefs in the US Caribbean Territories: Part I. Coral narrative rules

As coral reef condition and sustainability continue to decline worldwide, losses of critical habitat and their ecosystem services have generated an urgency to understand and communicate reef response to management actions, environmental contamination, and natural disasters. Increasingly, coral reef protection and restoration programs emphasize the need for robust assessment tools for protecting high-quality waters and establishing conservation goals. Of equal importance is the need to communicate assessment results to stakeholders, beneficiaries, and the public so that environmental consequences of decisions are understood. The Biological Condition (BCG) model provides a structure to evaluate the condition of a coral reef in increments of change along a gradient of human disturbance. Communication of incremental change, regardless of direction, is important for decision makers and the public to better understand what is gained or lost depending on what actions are taken. We developed a narrative (qualitative) Biological Condition Gradient (BCG) from the consensus of a diverse expert panel to provide a framework for coral reefs in US Caribbean Territories. The model uses narrative descriptions of biological attributes for benthic organisms to evaluate reefs relative to undisturbed or minimally disturbed conditions. Using expert elicitation, narrative decision rules were proposed and deliberated to discriminate among six levels of change along a gradient of increasing anthropogenic stress. Narrative rules for each of the BCG levels are presented to facilitate the evaluation of benthic communities in coral reefs and provide specific narrative features to detect changes in coral reef condition and biological integrity. The BCG model can be used in the absence of numeric, or quantitative metrics, to evaluate actions that may encroach on coral reef ecosystems, manage endangered species habitat, and develop and implement management plans for marine protected areas, watersheds, and coastal zones. The narrative BCG model is a defensible model and communication tool that translates scientific results so the nontechnical person can understand and support both regulatory and non-regulatory water quality and natural resource programs.

Puerto Rico, U.S. Virgin Islands↗
USGS2021

Similarities and differences between two deadly Caribbean coral diseases: White plague and stony coral tissue loss disease

For several decades, white plagues (WPDs: WPD-I, II and III) and more recently, stony coral tissue loss disease (SCTLD) have significantly impacted Caribbean corals. These diseases are often difficult to separate in the field as they produce similar gross signs. Here we aimed to compare what we know about WPD and SCTLD in terms of: (1) pathology, (2) etiology, and (3) epizootiology. We reviewed over 114 peer-reviewed publications from 1973 to 2021. Overall, WPD and SCTLD resemble each other macroscopically, mainly due to the rapid tissue loss they produce in their hosts, however, SCTLD has a more concise case definition. Multiple-coalescent lesions are often observed in colonies with SCTLD and rarely in WPD. A unique diagnostic sign of SCTLD is the presence of bleached circular areas when SCTLD lesions are first appearing in the colony. The paucity of histopathologic archives for WPDs for multiple species across geographies makes it impossible to tell if WPD is the same as SCTLD. Both diseases alter the coral microbiome. WPD is controversially regarded as a bacterial infection and more recently a viral infection, whereas for SCTLD the etiology has not been identified, but the putative pathogen, likely to be a virus, has not been confirmed yet. Most striking differences between WPD and SCTLD have been related to duration and phases of epizootic events and mortality rates. While both diseases may become highly prevalent on reefs, SCTLD seems to be more persistent even throughout years. Both transmit directly (contact) and horizontally (waterborne), but organism-mediated transmission is only proven for WPD-II. Given the differences and similarities between these diseases, more detailed information is needed for a better comparison. Specifically, it is important to focus on: (1) tagging colonies to look at disease progression and tissue mortality rates, (2) tracking the fate of the epizootic event by looking at initial coral species affected, the features of lesions and how they spread over colonies and to a wider range of hosts, (3) persistence across years, and (4) repetitive sampling to look at changes in the microbiome as the disease progresses. Our review shows that WPDs and SCTLD are the major causes of coral tissue loss recorded in the Caribbean.

Frontiers in Marine Science↗
USGS2020

Structural impacts, carbon losses, and regeneration in mangrove wetlands after two hurricanes on St. John, U.S. Virgin Islands

Hurricanes Irma and Maria ravaged the mangroves of St. John, U.S. Virgin Islands, in 2017. Basal area losses were large (63–100%) and storm losses of carbon associated with aboveground biomass amounted to 11.9–43.5 Mg C/ha. Carbon biomass of dead standing trees increased 8.1–18.3 Mg C/ha among sites, and carbon in coarse woody debris on the forest floor increased 1.9–18.2 Mg C/ha, with effects varying by mangrove typology. While St. John has only ~45 ha of mangroves, they exist as isolated basins, salt ponds, and fringe mangroves; the latter sometimes support diverse marine communities. Salt pond and fringe mangroves had proportionately more organic carbon (46.3 Mg C/ha) than inorganic carbon (1.1 Mg C/ha) in soils than isolated basins. Soil organic carbon was also appreciable in isolated basins (30.8 Mg C/ha) but was matched by inorganic C (36.7 Mg C/ha), possibly due to adjacent land use history (e.g., road construction), previous storm overwash, or geomorphology. Soil nitrogen stocks were low across all typologies. Mangroves had limited regeneration 26 months after the storms, and recovery on St. John may be hindered by pre-storm hydrologic change in some stands, and potential genetic bottlenecks and lack of propagule sources for expedient recovery in all stands.

St Johns↗
USGS2020

Disturbances drive changes in coral community assemblages and coral calcification capacity

Anthropogenic environmental change has increased coral reef disturbance regimes in recent decades, altering the structure and function of many coral reefs globally. In this study, we used coral community survey data collected from 1996 to 2015 to evaluate coral calcification capacity (CCC) dynamics with respect to recorded pulse disturbances for 121 reef sites in the Main Hawaiian Islands and Mo'orea (French Polynesia) in the Pacific and the Florida Keys Reef Tract and St. John (U.S. Virgin Islands) in the Western Atlantic. CCC remained relatively high in the Main Hawaiian Islands in the absence of recorded widespread disturbances; declined and subsequently recovered in Mo'orea following a crown-of-thorns sea star outbreak, coral bleaching, and major cyclone; decreased and remained low following coral bleaching in the Florida Keys Reef Tract; and decreased following coral bleaching and disease in St. John. Coral taxa have diverse calcification rates and susceptibility to disturbances characterized by their life history strategies. As a result, changes in CCC over the time series in this study were driven by a combination of shifts in both overall coral cover and in the contributions of calcification by the dominant calcifying coral taxa to CCC. Analysis of coral life history strategies showed that ‘weedy’ corals increased their contributions to CCC over time while ‘competitive’ corals decreased. Conversely, shifts in contributions by ‘stress-tolerant’ and ‘generalist’ corals to CCC varied by taxa across the regions. The increasing frequency and intensity of disturbances under 21st century global change is therefore predicted to affect CCC for many coral reefs with potentially lower and more variable CCC sustained under increased disturbance regimes by the increasing dominance of ‘weedy’ and some ‘stress-tolerant’ corals.

Ecosphere↗
USGS2019

Immediate effects of hurricanes on a diverse coral/mangrove ecosystem in the U.S. Virgin Islands and the potential for recovery

Hurricanes Irma and Maria, two powerful storms that hit the U.S. Virgin Islands less than 2 weeks apart in September 2017, caused extensive damage to the natural resources on St. John. Damage was particularly severe in a unique mangrove/coral ecosystem in three bays within Virgin Islands Coral Reef National Monument, a National Park Service marine protected area. Many Red Mangrove ( Rhizophora mangle ) trees were uprooted and tossed into the sea, and the prop roots of others were stripped of corals, sponges and other marine life. No other mangrove area in the Caribbean is known to have so many scleractinian corals (about 30 species before the storms). Although many corals were overturned or buried in rubble, colonies of most of the species, including four that are listed as threatened under the U.S. Endangered Species Act, survived. Recovery of this ecosystem will depend on Red Mangrove propagules becoming established and producing prop roots to support rich marine life along with a canopy to provide the shade that was critical to the biodiversity that was present before the storms. Unlike in many situations where major disturbances reduce coral cover, the substrate that must be restored for full recovery to occur is a living substrate—the prop roots of the mangroves. Larvae of corals and sponges will need to recruit on to the roots. Future storms could hinder this process.

Diversity↗
USGS2019

What nutrient sources support anomalous growth and the recent sargassum mass stranding on Caribbean beaches? A review

Since 2011, tropical beaches from Africa to Brazil, Central America, and the Caribbean have been inundated by tons of sargassum seaweed from a new equatorial source of pelagic sargassum in the Atlantic. In recent years the extraordinary accumulations of sargassum make this a nuisance algal bloom for tropical coasts. In 2018 satellite data indicated floating mats of sargassum that extended throughout the Caribbean to the northeast coast of Brazil with the highest percent coverage over the water yet recorded. A literature review suggests that Atlantic equatorial recirculation of seaweed mats combined with nutrients from several possible sources may be stimulating the growth and accumulations of sargassum. In the western equatorial recirculation area, new nutrient sources may include Amazon River floods and hurricanes; in the eastern equatorial recirculation area, nutrient sources that could sustain the sargassum blooms include coastal upwelling and Congo River freshwater and nutrients.

Marine Pollution Bulletin↗
USGS2019

The circumtropical swarm population of the longspined porcupinefish (Diodon holocanthus Linnaeus)

Evidence is presented that Diodon holocanthus is a circumtropical swarm (not a hybrid swarm because the individuals are not hybrids). Some individuals are so different from one another in both color and morphology that they appear to be different species. Thirty undersea and aquarium photographs from different global localities are provided to demonstrate the variability. The worldwide distribution is achieved by the juvenile that has been found more than 1,000 km offshore as large as 90 mm SL. How can it feed on zooplankton with jaws and dentition designed to crush shelled invertebrates? We believe it draws the prey into the mouth with the same mechanism that it uses to expand its body when threatened; the water with prey is diverted to the pharyngeal cavity, then released from the gill opening on each side. Larger juveniles may seek concentrations of zooplankton for feeding, perhaps collectively. A confirming experiment in an aquarium is advised. Aggregations of pelagic juveniles have been observed at the surface outside barrier reefs and found inshore the following morning, indicating that settlement took place at night to minimize predation. The juveniles soon disperse to inshore habitats of mangrove and sea grass to coral reef. The hybrid Diodon holocanthus x D. hystrix from South Africa is illustrated. The narrative for the present research on D. holocanthus is presented chronologically to show how increasing evidence failed to support the multitude of apparent new species of Diodon , leading to the conclusion of a swarm.

Aqua↗