Charleston County Research Articles

Testing of Shoreline Erosion Monitoring Methodologies for Heritage at Risk Sites: Pockoy Island, South Carolina, USA

Abstract We review shoreline monitoring methodologies used by members of the South Carolina Department of Natural Resources (SCDNR) Archaeology, Geology, and Wildlife Biology teams from February 2021 to December 2022 on Pockoy Island in Charleston County, South Carolina, USA. Our project objectives were to better understand the driving forces behind the landward movement of the shoreline (transgression), to apply new understanding to the rate of shoreline erosion of the island that directly impacts the Pockoy Island Shell Ring Complex (38CH2533), and to establish best practice for future community science monitoring efforts. Each member of our team used a different shoreline monitoring methodology (a nested methodology approach). Multiple unoccupied aerial vehicle (UAV)-derived orthoimagery datasets, on-the-ground transect measurements, and Arrow Gold real-time kinematic (RTK) unit measurements have been collected monthly following significant storms or king (perigean) tide events. Moving forward, the erosion transect approach tested within this project will serve as the foundation for community science monitoring at heritage at-risk sites in South Carolina. In this article, we introduce initial efforts in establishing a community science monitoring program in South Carolina that will influence future research, land management, and policy, and we propose how our research might be adapted for other sites at risk.

Differential susceptibility of two Citrullus amarus pollenizer watermelons to five species of Pythium and Globisporangium.

Pollenizer watermelon (Citrullus amarus) must be planted alongside triploid watermelon cultivars to provide a source of pollen. Early season death of pollenizer watermelon cultivars SP-6 and SP-7 was observed in a research field in Charleston County, South Carolina, in April 2022, 3 to 4 weeks after transplanting. Disease incidence was 15% and 12% for the two cultivars, respectively. Two species of Pythium, P. myriotylum (four isolates) and P. aphanidermatum (three isolates), and three species of Globisporangium, G. ultimum (one isolate), G. irregulare (one isolate), and G. spinosum (four isolates), were recovered from 13 of 17 plants cultured and identified based on the sequences of the cytochrome c oxidase subunit I gene. Pythium spp. were recovered from both cultivars, while Globisporangium spp. were recovered only from SP-7. In pathogenicity tests, SP-7 had lower area under the disease progress curve (AUDPC) values than SP-6 with one isolate each of four species and lower AUDPC values than seedless watermelon Estrella with one isolate each of two species. Mean AUDPC values did not differ between Estrella and SP-6 with any isolate. AUDPC values were greater with G. ultimum on all three cultivars than with one isolate of G. spinosum and both isolates of P. myriotylum and P. aphanidermatum. Susceptibility of the new cultivar SP-7 to Pythium and Globisporangium spp. differs from susceptibility of SP-6. These results will help growers choose which pollenizer cultivar to plant.

Noteworthy Collections—South Carolina

Discussion is provided for an occurrence of Macbridea caroliniana thought to be extirpated (Berkeley County) and five new occurrences collected 2019–2020 on the South Carolina Coastal Plain. One new occurrence is a county record (Charleston County). Four new occurrences along the Black River through Berkeley and Williamsburg counties suggest favorable habitat in that region. Findings suggest that this species may be underreported in South Carolina and effort should be placed in identifying disturbed habitat in conserved natural areas that may harbor this rare plant.

A shared-mobility-based framework for evacuation planning and operations under forecast uncertainty

To meet evacuation needs from carless populations who need personalized assistance to evacuate safely, in this article we propose a ridesharing-based evacuation program that recruits volunteer drivers before a disaster strikes, and then matches volunteer drivers with evacuees once demand is realized. We optimize resource planning and evacuation operations under uncertain spatiotemporal demand, and construct a two-stage stochastic mixed-integer program to ensure high demand fulfillment rates. We consider three formulations to improve the number of evacuees served, by minimizing an expected penalty cost, imposing a probabilistic constraint, and enforcing a constraint on the conditional value at risk of the total number of unserved evacuees, respectively. We discuss the benefits and disadvantages of the different risk measures used in the three formulations, given certain carless population sizes and the variety of evacuation modes available. We also develop a heuristic approach to provide quick, dynamic and conservative solutions. We demonstrate the performance of our approaches using five different networks of varying sizes based on regions of Charleston County, South Carolina, an area that experienced a mandatory evacuation order during Hurricane Florence, and utilize real demographic data and hourly traffic count data to estimate the demand distribution.

Integrated socio-environmental vulnerability assessment of coastal hazards using data-driven and multi-criteria analysis approaches

Coastal hazard vulnerability assessment has been centered around the multi-variate analysis of geo-physical and hydroclimate data. The representation of coupled socio-environmental factors has often been ignored in vulnerability assessment. This study develops an integrated socio-environmental Coastal Vulnerability Index (CVI), which simultaneously combines information from five vulnerability groups: biophysical, hydroclimate, socio-economic, ecological, and shoreline. Using the Multi-Criteria Decision Making (MCDM) approach, two CVI (CVI-50 and CVI-90) have been developed based on average and extreme conditions of the factors. Each CVI is then compared to a data-driven CVI, which is formed based on Probabilistic Principal Component Analysis (PPCA). Both MCDM and PPCA have been tied into geospatial analysis to assess the natural hazard vulnerability of six coastal counties in South Carolina. Despite traditional MCDM-based vulnerability assessments, where the final index is estimated based on subjective weighting methods or equal weights, this study employs an entropy weighting technique to reduce the individuals’ biases in weight assignment. Considering the multivariate nature of the coastal vulnerability, the validation results show both CVI-90 and PPCA preserve the vulnerability results from biophysical and socio-economic factors reasonably, while the CVI-50 methods underestimate the biophysical vulnerability of coastal hazards. Sensitivity analysis of CVIs shows that Charleston County is more sensitive to socio-economic factors, whereas in Horry County the physical factors contribute to a higher degree of vulnerability. Findings from this study suggest that the PPCA technique facilitates the high-dimensional vulnerability assessment, while the MCDM approach accounts more for decision-makers' opinions.

Strategies For Responding To Inequity: A Conversation With Black Leadership

Sponsored by the Roundtable for African American Concerns (RAAC) of the South Carolina Library Association (SCLA), this session featured African American representation from various levels of Charleston County Public Library management. Each panelist discussed their experiences of racial inequity (Individual, Institutional, and Structural), finding and being advocates, coping and self-care methods, and positive outcomes. Panelists also offered strategies and solutions for handling inequity. The article discusses what was the catalyst leading to the deliberate, purposeful efforts of Charleston County Public Library to include Equity as one of the core principles in its Strategic Vision for 2021-2024.

Mental health needs assessment of individuals experiencing homelessness in Charleston, South Carolina.

More than 4,268 people were experiencing homelessness in South Carolina during the 2020 point in time count, with Charleston county ranked the 4th highest in the state for number of individuals experiencing homelessness. Mental health disorders often contribute to or result from housing insecurity. The purpose of this quality improvement study was to determine mental health needs, and mental health services utilization patterns of people experiencing homelessness or housing insecurity (PEH) in Charleston, SC. Cross sectional survey, utilizing a 13 question paper survey. Drop-in resource center for PEH. 33 PEH accessing the resource center. 1. Demographics 2. Mental health needs 3. Access to mental health resources and 4. Preferences for accessing mental health services. Survey participants (n=33) ranged from 19 to 64 years old with 57.6% identifying as male and 51.5% identifying as Black. More than three quarters (81.3%) of those surveyed reported being diagnosed with at least one psychiatric disorder. Over half (56.3%) had been hospitalized for a psychiatric reason. Over two thirds (70.0%) were accessing some form of mental health service and 51.9% endorsed some difficulty accessing prescribed psychiatric medications. Cost and transportation were selected most often as barriers to access. Most participants (92.9%) were interested in receiving some form of mental health service and 62.5% said access to services would make it easier to get stable housing. Most (85.2%) were willing to access mental health services virtually, however, 50.0% of participants did not report access to an electronic device and most (74.1%) denoted preference for in person services. PEH have significant mental health needs and experience barriers to accessing mental health services. Resources directed at addressing these barriers are essential to improve the mental health of this vulnerable population and ameliorate housing instability.

First Report of Colletotrichum scovillei Causing Anthracnose Fruit Rot on Pepper in South Carolina, United States.

Anthracnose fruit rot caused by various Colletotrichum spp. is a serious disease for pepper (Capsicum annuum) growers, resulting in extensive fruit loss (Harp et al. 2008). Samples of five pepper fruits were obtained from two commercial farms in Lexington and Pickens counties, South Carolina, in August and September 2019, respectively. All fruits had two or more soft, sunken lesions covered with salmon-colored spore masses. Pieces of diseased tissue cut from the margins of lesions were surface disinfested in 0.6% sodium hypochlorite, rinsed in sterile deionized water, blotted dry, and placed on one-quarter-strength potato dextrose agar (PDA/4) amended with 100 mg chloramphenicol, 100 mg streptomycin sulfate, and 60.5 mg mefenoxam (0.25 ml Ridomil Gold EC) per liter. Two isolates of Colletotrichum sp. per fruit were preserved on dried filter paper and stored at 10º C. One additional isolate of Colletotrichum sp. had been collected from a jalapeño pepper fruit on a farm in Charleston County, South Carolina, in 1997. Colony morphology of three isolates, one per county, on Spezieller Nährstoffarmer Agar (SNA) was pale grey with a faint orange tint. All isolates readily produced conidia on SNA with an average length of 16.4 μm (std. dev. = 1.8 μm) and a width of 2.2 μm (std. dev. = 0.2 μm). Conidia were hyaline, smooth, straight, aseptate, cylindrical to fusiform with one or both ends slightly acute or round, matching the description of C. scovillei (Damm et al. 2012). The glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and beta-tubulin (TUB2) genes from three isolates were amplified and sequenced with the primer pairs GDF1/GDR1 and T1/Bt2b, respectively. Species within the C. acutatum clade can be readily distinguished with GAPDH or TUB2 (Cannon et al. 2012). The GAPDH and TUB2 sequences for all three isolates were 100% similar to each other and strain CBS 126529 (GAPDH accession number JQ948597; TUB2 accession number JQ949918) of C. scovillei (Damm et al. 2012). GAPDH and TUB2 sequences for each isolate were deposited in GenBank under the accessions MT826948-MT826950 and MT826951-MT826953, respectively. A pathogenicity test was conducted on jalapeño pepper fruits by placing a 10-ul droplet of a 5 x 105 conidial suspension of each isolate onto a wound made with a sterile toothpick. Control peppers were mock inoculated with 10 ul sterile distilled water. A humid chamber was prepared by placing moist paper towels on the bottom of a sealed crisper box. Inoculated peppers were placed on upside-down 60 ml plastic condiment cups. Three replicate boxes each containing all four treatments were prepared. The experiment was repeated once. After 7 days in the humid chamber at 26ºC, disease did not develop on control fruits, whereas soft, sunken lesions covered with salmon-colored spores developed on inoculated fruits. Lesions were measured and C. scovillei was re-isolated onto amended PDA/4 as previously described. Lesion length averaged 15.6 mm (std dev. = 4.1 mm) by 11.5 mm (std dev. = 2.0 mm). Colletotrichum sp. resembling the original isolate were recovered from all inoculated fruit, but not from non-inoculated fruit. C. scovillei has been reported in Brazil in South America and in China, Indonesia, Japan, Malaysia, South Korea, Taiwan, and Thailand in Asia (Farr and Rossman 2020). This is the first report of C. scovillei as the casual organism of anthracnose fruit rot on pepper in South Carolina and the United States.

Perfluoroalkyl substances in diamondback terrapins (Malaclemys terrapin) in coastal South Carolina

This study focused on an estuarine wildlife species exhibiting high site fidelity and ubiquitous distribution in coastal environments along the Atlantic and Gulf coasts of the United States to monitor per- and polyfluoroalkyl substances (PFAS). A total of 75 diamondback terrapin (Malaclemys terrapin) plasma samples were collected from five creeks associated with Kiawah (Oyster Creek, Fiddler Creek, Sandy Creek, Gnat Creek) and Edisto (Townsend Creek) islands in Charleston County, South Carolina and investigated for 15 legacy PFAS. Of those, PFHxS was the only PFAS found in all terrapin plasma samples. Four additional PFAS were routinely detected (greater than 90% of the samples) and were included in statistical analyses: PFOS, PFNA, PFDA, and PFUnA. Sex-differences were observed for two creeks with male plasma containing higher PFAS than female plasma (PFHxS at Townsend Creek, PFOS at Oyster Creek). Sex-specific site differences in PFAS concentrations were observed primarily for males, suggesting male terrapins may be more sensitive indicators of localized contaminant profiles than females. Three PFAS were observed to have negative correlations with body mass: PFOS in males (p = 0.045, tau = −0.220), PFNA in males (p = 0.016, tau = −0.269), and PFHxS in both males (p = 0.007, tau = −0.302) and females (p = 0.001, tau = −0.379). No relationships for body mass and PFDA and PFUnA were observed.

McLeod Plantation Historic Site

In 2015 the Charleston County Park and Recreation Commission opened McLeod Plantation Historic Site. What remains of the former 1,693-acre Sea Island cotton plantation is 37 acres, 14 historic structures, and an African American cemetery. Interpretation of the former plantation is focused on the African American struggle to achieve freedom, justice, and equality from 1851 through 1990. The cultural history interpretation coordinator and co-author of the National Association for Interpretation award winning exhibits at the site explores the development, implementation, and adjustments made to interpretation since the opening and comments on the current state of Black museums in America.

Power Laws in Real Estate Prices? Some Evidence

Power law distributions have previously been observed in data like city-size distributions (Zipf’s Law), income distributions, and financial asset prices. In this paper, we explore the distribution of real estate prices in Charleston County, South Carolina. We fit power law, lognormal and exponential distributions to the data and compare the goodness of fit among the distributions. We find that the best fit distribution lies somewhere between the lognormal and power law distributions. We estimate how the power law exponent changes over time and find a potential relationship between the shape of the power law distribution and the bursting of the real estate bubble in 2007.

First Report of Cucurbit Leaf Crumple Virus Infecting Three Cucurbit Crops in South Carolina

Virus-like symptoms of curled and crumpled leaves, bright yellow chlorosis, and marginal leaf necrosis typical of begomovirus infection were observed on watermelon, summer squash, and muskmelon in three counties in South Carolina in August 2017. Genus-specific primers for begomovirus-A and begomovirus-B components produced amplicons of the expected sizes. Sanger sequencing of amplicons from both A and B components and BLASTn analysis revealed a high nucleotide sequence identity in seven watermelon samples from Beaufort and Charleston counties and five muskmelon samples from Charleston County with cucurbit leaf crumple virus.

Power Laws in Real Estate Prices? Some Evidence

Power law distributions have previously been observed in data like city-size distributions (Zipf’s Law), income distributions, and financial asset prices. In this paper we explore the distribution of real estate prices in Charleston County, South Carolina. We fit both a power law, lognormal and exponential distributions to the data and compare the goodness of fit among the distributions. We find that the best fit distribution lies somewhere between the lognormal and power law distributions. We estimate how the power law exponent changes over time and find a potential relationship between the shape of the power law distribution and the bursting of the real estate bubble in 2007.

Coastal TDRs: A Solution for Shifting Sands on Folly Beach?

ABSTRACTFolly Beach, South Carolina is in dire straits. Severe coastal erosion and controversial beach renourishment projects have raised serious concerns for the immediate future of the beach and surrounding coastal community. Deciding on a course of action to address these issues has led to conflicts between policymakers, property owners, and members of the public, particularly because traditional ideas are so unpalatable: the use of additional hard erosion control devices is not only environmentally objectionable, but also heavily restricted under South Carolina law; beach-wide renourishment projects provide temporary solutions but are expensive and often fraught with problems; and the taking of at-risk beachfront property under either the state or city's eminent domain power presents both legal and financial hurdles. This article considers whether a system of Transferable Development Rights (TDRs), a market-based mechanism grounded in economic incentives, could be a viable solution for Folly Beach's erosion-related problems. In theory, by incentivizing relocation and inland development, a properly implemented TDR program in Charleston County could protect its public trust beaches in furtherance of South Carolina's stated coastal management policy of retreat from the shoreline.

Abstract A07: Exploring the distribution of environmental cancer risk by air toxics using geographic information systems

Abstract We examined environmental cancer risk disparities in Metropolitan Charleston by determining the variability in cancer risk and outcomes geographically by racial and socioeconomic characteristics. We mapped total cancer risk from the 2005 National-Scale Air Toxics Assessment (NATA) and five-year (2006-2010) cancer outcomes (incidence and mortality) from the South Carolina Central Cancer Registry. Data were georeferenced to the 2000 Decennial United States Census tract boundaries in Metropolitan Charleston (i.e. Berkeley, Charleston, and Dorchester County). A Spearman's rank-order correlation was run to determine the relationship between cancer risk or cancer outcomes and characteristics of environmental justice (percent (%) Black, poverty, and low-income). Correlations were performed in SPSS 22.0. Bivariate choropleth maps were created in ArcGIS 10.2 to represent the geographic associations between cancer data and environmental justice variables. Our findings demonstrate an inverse relationship between cancer risk and five-year cancer incidence (rs = -1.90, p = .040). Cancer risk was positively correlated with % Black (rs = .324) and % poverty (rs = .474), yet negatively related to % income (rs = -.542). Bivariate maps showed that 80% of the tracts with high cancer incidence/high percent Black population were simultaneously high cancer mortality/high Black population tracts. None of the high incidence or high mortality tracts had simultaneously high cancer risk. Findings from this study have implications for reducing place-based environmental cancer disparities. With a better understanding of patterns of risk, public health professionals can tailor interventions and develop community-based environmental health programs that will inform policies to reduce cancer inequities. Citation Format: LaShanta J. Rice, Christopher T. Emrich, Heather M. Brandt, Lucy Annang Ingram, James W. Hardin, Sacoby M. Wilson, Chanita Hughes Halbert. Exploring the distribution of environmental cancer risk by air toxics using geographic information systems. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr A07.

Affordability of the National Flood Insurance Program: Application to Charleston County, South Carolina

AbstractIn March 2014, Congress passed legislation delaying the phasing-in of premium increases on discounted flood insurance policies that had been authorized in July 2012 by the Biggert-Waters Flood Insurance Reform Act. This reversal highlights the tension between the realization of risk-based premiums and affordability of flood insurance for homeowners in flood-prone areas. This study on Charleston County, South Carolina, seeks to understand how the tension can be resolved using a voucher program coupled with required mitigation. It specifically focuses on home elevation as the mitigation method. This paper demonstrates a potential average increase of 108 to 159% for high-risk single-family properties in Special Flood Hazard Areas in Charleston moving from a current discounted premium to a full risk-based premium as proposed by the 2012 legislation. Implementation of the proposed voucher program coupled with required mitigation can reduce government expenditures by more than half over a program that d...

Post-hoc analysis of vitamin D status and reduced risk of preterm birth in two vitamin D pregnancy cohorts compared with South Carolina March of Dimes 2009–2011 rates

BackgroundTwo vitamin D pregnancy supplementation trials were recently undertaken in South Carolina: The NICHD (n=346) and Thrasher Research Fund (TRF, n=163) studies. The findings suggest increased dosages of supplemental vitamin D were associated with improved health outcomes of both mother and newborn, including risk of preterm birth (<37 weeks gestation). How that risk was associated with 25(OH)D serum concentration, a better indicator of vitamin D status than dosage, by race/ethnic group and the potential impact in the community was not previously explored. While a recent IOM report suggested a concentration of 20ng/mL should be targeted, more recent work suggests optimal conversion of 25(OH)D–1,25(OH)2D takes place at 40ng/mL in pregnant women. ObjectivePost-hoc analysis of the relationship between 25(OH)D concentration and preterm birth rates in the NICHD and TRF studies with comparison to Charleston County, South Carolina March of Dimes (CC-MOD) published rates of preterm birth to assess potential risk reduction in the community. MethodsUsing the combined cohort datasets (n=509), preterm birth rates both for the overall population and for the subpopulations achieving 25(OH)D concentrations of ≤20ng/mL, >20 to <40ng/mL, and ≥40ng/mL were calculated; subpopulations broken down by race/ethnicity were also examined. Log-binomial regression was used to test if an association between 25(OH)D serum concentration and preterm birth was present when adjusted for covariates; locally weighted regression (LOESS) was used to explore the relationship between 25(OH)D concentration and gestational age (weeks) at delivery in more detail. These rates were compared with 2009–2011 CC-MOD data to assess potential risk reductions in preterm birth. ResultsWomen with serum 25(OH)D concentrations ≥40ng/mL (n=233) had a 57% lower risk of preterm birth compared to those with concentrations ≤20ng/mL [n=82; RR=0.43, 95% confidence interval (CI)=0.22,0.83]; this lower risk was essentially unchanged after adjusting for covariates (RR=0.41, 95% CI=0.20,0.86). The fitted LOESS curve shows gestation week at birth initially rising steadily with increasing 25(OH)D and then plateauing at ∼40ng/mL. Broken down by race/ethnicity, there was a 79% lower risk of preterm birth among Hispanic women with 25(OH)D concentrations ≥40ng/mL (n=92) compared to those with 25(OH)D concentrations ≤20ng/mL (n=29; RR=0.21, 95% CI=0.06,0.69) and a 45% lower risk among Black women (n=52 and n=50; RR=0.55, 95% CI=0.17,1.76). There were too few white women with low 25(OH)D concentrations for assessment (n=3). Differences by race/ethnicity were not statistically significant with 25(OH)D included as a covariate.Compared to the CC-MOD reference group, women with serum concentrations ≥40ng/mL in the combined cohort had a 46% lower rate of preterm birth overall (n=233, p=0.004) with a 66% lower rate among Hispanic women (n=92, p=0.01) and a 58% lower rate among black women (n=52, p=0.04). ConclusionsIn this post-hoc analysis, achieving a 25(OH)D serum concentration ≥40ng/mL significantly decreased the risk of preterm birth compared to ≤20ng/mL. These findings suggest the importance of raising 25(OH)D levels substantially above 20ng/mL; reaching 40ng/mL during pregnancy would reduce the risk of preterm birth and achieve the maximal production of the active hormone.

Combining automated vision screening with on-site examinations in 23 schools: ReFocus on Children Program 2012 to 2013.

The Association for the Blind and Visually Impaired (ABVI) began the ReFocus on Children Program to assist school nurses in providing vision screening for at-risk children in the Charleston County School District in South Carolina. In 2012 to 2013, 2,750 low-income school children ages 3 to 5 years were screened using the Plusoptix Vision screener (Atlanta, GA). Further examinations were performed on 419 (56%) children referred and glasses prescribed and provided for 192 children (positive predictive value 46%). In 2013, teacher feedback questionnaires were sent to the 23 schools. Teacher feedback questionnaires had a 49% response rate. Of teachers responding to the questionnaire, 70% reported the children liked wearing their glasses. Teachers provided observations of positive impact, including improved academic performance. Nurses appreciated that the entire process was efficient and completed in school, simplifying care and follow-up. The authors encourage partnerships between schools, nonprofit agencies, and healthcare providers to improve screening and access to comprehensive vision care for young children.

An In-Depth Analysis of the Houston-Galveston Area Council Regional Hazard Mitigation Plan Under the Disaster Mitigation Act of 2000 (DMA2K)

The Disaster Mitigation Act of 2000 (DMA2K) requires that each local government develop an individual mitigation plan or actively participate in the development of a multi-jurisdictional plan. Jurisdictions are required to collaborate with neighboring jurisdictions, agencies or departments, businesses, academic institutions, media, and non-profit organizations. This study is an indepth analysis of a multijurisidictional plan with multiple mitigation action plans (MAPS) to better understand the levels of coordination of activities both during the planning process and inclusion of collaboration in their MAPS. This study also investigated the inclusion of activities for public information and awareness, multiple hazards, evacuation procedures and communities for special considerations. The results of this study show that less than 45 percent of the jurisdictions incorporated collaboration, evacuation, and technological hazards, while less than 10 percent included sheltering, terrorism, and special needs population. Many political jurisdictions with different levels of exposure and vulnerability submitted the same MAPS, which negate the community specific approach of hazard mitigation. Results from HGAC analysis were compared with Charleston County, SC and showed that Charleston included more elements than those in HGAC. This study is a policy-learning tool, which provides information for review and revision of future plan updates.

Substratum fidelity and early growth in &lt;I&gt;Chelonibia testudinaria&lt;/I&gt;, a turtle barnacle especially common on debilitated loggerhead (&lt;I&gt;Caretta caretta&lt;/I&gt;) sea turtles

The barnacle, Chelonibia testudinaria (Linnaeus, 1758), is reported to associate with nearly every species of sea turtle and is particularly common on loggerheads, Caretta caretta (Linnaeus, 1758), with symptoms of Debilitated Turtle Syndrome (DTS). Here, we test recruitment rates of C. testudinaria on various natural and artificial substrata, including carapace from healthy and debilitated loggerheads. In addition, the sizes of individual barnacles were followed through time to estimate early growth rates and to provide attachment duration estimates. Floating racks holding replicate panels of four treatments (DTS turtle carapace scutes, healthy turtle carapace scutes, Plexiglas®, and slate tile) were placed at four independent sites in Charleston County, South Carolina. Panels were monitored for 34-54 d. Our findings indicate that C. testudinaria larvae recruit and grow at significantly higher rates along the open shore vs protected areas, but do not recruit differentially to the four substratum types. Individual barnacle growth was highly variable within and between sites and substratum types; the mean growth rate was 4.28 mm d-1 (95% CI: 3.42-5.14 mm d-1). However, due to the high variability in growth, this value cannot serve as a fine-scale indicator for attachment duration. Further experiments of substratum selection and long-term survival are needed to fully clarify the nature of the barnacle/turtle association.