Coral communities in the Caribbean face a new and deadly threat in the form of the
highly virulent multi-host stony coral tissue loss disease (SCTLD). In late January of 2019,
a disease with signs and characteristics matching that of SCTLD was found affecting
a reef off the coast of St. Thomas in the U.S. Virgin Islands (USVI). Identification of its
emergence in the USVI provided the opportunity to document the initial evolution of
its spatial distribution, coral species susceptibility characteristics, and its comparative
impact on coral cover at affected and unaffected coral reef locations. Re-assessments
at sentinel sites and long-term monitoring locations were used to track the spread of
the disease, assess species affected, and quantify its impact. The disease was initially
limited to the southwest of St. Thomas for several months, then spread around the
island and to the neighboring island of St. John to the east. Differences in disease
prevalence among species were similar to reports of SCTLD from other regions.
Highly affected species included Colpophyllia natans, Eusmilia fastigiata, Montastraea
cavernosa, Orbicella spp., and Pseudodiploria strigosa. Dendrogyra cylindrus and
Meandrina meandrites were also highly affected but showed more variability in disease
prevalence, likely due to initial low abundances and the rapid loss of colonies due to
disease. Siderastrea spp. were less affected and showed lower prevalence. Species
previously reported as unaffected or data deficient that were found to be affected
by SCTLD included Agaricia spp., Madracis spp., and Mycetophyllia spp. We also
observed multi-focal lesions at SCTLD-affected sites on colonies of Porites astreoides,
despite that poritids have previously been considered low or not susceptible to SCTLD.
Loss of coral cover due to acute tissue loss diseases, which were predominantly SCTLD,
was significant at several monitoring locations and was more impactful than previous
mass bleaching events at some sites. There are no signs that the USVI SCTLD outbreak
is abating, therefore it is likely that this disease will become widespread across the U.S.
Caribbean and British Virgin Islands in the near future.
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Caribbean Resilience of Infrastructure in the United States Virgin Islands
f. Analyzing the US Virgin Islands’ resilience in relation to their infrastructure in the case of natural disasters - The U.S. Virgin Islands are comprised of four islands in the Caribbean: St. Croix, St. Thomas, St. John, and Water Island. With the high frequency of hurricanes in the Caribbean region, these islands commonly experience infrastructure disruptions. Worse, disasters such as Irma and Maria in 2017 make total losses far from unexpected. The islands have also seen a history of economic and political turmoil, rendering their infrastructure insufficient for resisting such devastating events and the lower class more susceptible to disruptions. These factors combined posits the need for resilient infrastructure to be established on the islands. Resilient infrastructure involves bolstering the utilities that are required for modern life, such as clean water, power, and transportation, such that they maintain the highest output possible when disrupted by a disaster and can be easily and effectively restored to their status quo. Our work this semester focused on assessing the infrastructure on the islands to energy options could be better implemented. This has involved gathering as much quantitative and qualitative data on the USVI as possible. This was done in order to perform a rigorous analysis on which sections of the network are most necessary for the interconnected systems network together to function; these sections are known as critical points. Only so much data is available overseas, however, so to complete our assessment we will identify what we need to fill in the gaps in our data by working in collaboration with the University of the Virgin Islands. We are constructing an accurate disaster model of the USVI infrastructure and determine its critical points as well as make recommendations for additional hazard and mitigation plans. We will then focus on getting these recommendations to the right positions of power, which could lead to establishing resilient infrastructure on the island and pave the way to a more sustainable future. In the future, we hope to create a cooperative learning bond with the University of the Virgin Islands so that future applications of the project can proceed.
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- Award ID(s):
- 1633608
- NSF-PAR ID:
- 10341171
- Date Published:
- Journal Name:
- CEDC Summit 2020
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Upright branching sponges, such as
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.13140/RG.2.2.15862.14405
