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Coral reefs in southeast Florida have experienced severe losses in coral cover and diversity in recent decades, primarily due to disease outbreaks and bleaching events exacerbated by anthropogenic impacts. Subsequent increases in "weedy" coral species like Agaricia spp. and Porites spp. have been observed on many reefs in this region. At the northernmost boundary of the Florida's Coral Reef, St. Lucie Reef in Martin County has experienced a particularly notable increase in the abundance of Porites astreoides. To identify potential larval sources and P. astreoides population dynamics that may be contributing to observed coral community shifts, we sampled P. astreoides across five locations in southeast Florida from St. Lucie Reef to Fort Lauderdale and assessed population genetic structure using 2bRAD sequencing to generate single-nucleotide polymorphism (SNP) data. We identified high rates of clonality within and among the sample populations. Despite the brooding reproductive strategy of P. astreoides, there were relatively high levels of connectivity among populations and varying levels of genetic structure which correlated with geographic gradients. The genetic diversity and connectivity data reported here for P. astreoides populations in southeast Florida suggest that recent increases in abundance may be driven by high fecundity and long-range dispersal of a few successful genotypes. [ABSTRACT FROM AUTHOR]

Urbanization and warming climate suggest that health impacts from extreme heat will increase in cities, thus locating vulnerable populations is pivotal. However, heat vulnerability indices (HVI) overwhelmingly interpret one model that may be inaccurate or methodologically flawed without considering how results compare with other HVI. Accordingly, this analysis applied a multimodal approach incorporating underrepresented health and adaptability measures to analyze heat vulnerability more comprehensively and better identify vulnerable populations. The Southeast Florida HVI (SFHVI) blends twenty-four physical exposure, sensitivity, and adaptive capacity indicators using uncommon statistical weights removing overlap, then SFHVI scores were compared statistically and qualitatively with ten models utilizing alternative methods. Urban areas with degraded physical settings, socioeconomic conditions, health, and household resources were particularly vulnerable. Rural and agricultural areas were also vulnerable reflecting socioeconomic conditions, health, and community resources. Three alternative models produced vulnerability scores not statistically different than SFHVI. The other seven differed significantly despite geospatial consistency regarding the most at-risk areas. Since inaccurate HVI can mislead decisionmakers inhibiting mitigation, future studies should increasingly adopt multimodal approaches that enhance analysis comprehensiveness, illuminate methodological strengths and flaws, as well as reinforce conviction about susceptible populations. [ABSTRACT FROM AUTHOR]

Atlantic bottlenose dolphins (Tursiops truncatus) are frequently observed in the coastal waters of Palm Beach County, Florida. In this study, markrecapture surveys using photo-identification techniques were used to estimate population abundance of Atlantic bottlenose dolphins in this area for the first time. Surveys were conducted for 11 years, between 2005 and 2016, during which 384 individuals were identified and catalogued from distinctive nicks and notches on their dorsal fins. Each marked individual was documented an average of 2.4 times (range 1 to 19). Low resighting rates and a constant rate of encounter with previously unmarked individuals suggest that the population is open, comprising both residents and transients. The Jolly-Seber method was used to estimate population abundance. Estimates of abundance varied greatly in time with an overall average of 264 individuals and a 95% confidence interval of 162 to 366 (SE = 51.3), indicating a variable population size. As threats in the region continue to rise, such as overfishing, toxic algae blooms, and environmental pollutants, this understudied population may be vulnerable to decline. A better understanding of the population dynamics could facilitate more effective conservation action. [ABSTRACT FROM AUTHOR]

Urbanization and warming climate suggest that health impacts from extreme heat will increase in cities, thus locating vulnerable populations is pivotal. However, heat vulnerability indices (HVI) overwhelmingly interpret one model that may be inaccurate or methodologically flawed without considering how results compare with other HVI. Accordingly, this analysis applied a multimodal approach incorporating underrepresented health and adaptability measures to analyze heat vulnerability more comprehensively and better identify vulnerable populations. The Southeast Florida HVI (SFHVI) blends twenty-four physical exposure, sensitivity, and adaptive capacity indicators using uncommon statistical weights removing overlap, then SFHVI scores were compared statistically and qualitatively with ten models utilizing alternative methods. Urban areas with degraded physical settings, socioeconomic conditions, health, and household resources were particularly vulnerable. Rural and agricultural areas were also vulnerable reflecting socioeconomic conditions, health, and community resources. Three alternative models produced vulnerability scores not statistically different than SFHVI. The other seven differed significantly despite geospatial consistency regarding the most at-risk areas. Since inaccurate HVI can mislead decisionmakers inhibiting mitigation, future studies should increasingly adopt multimodal approaches that enhance analysis comprehensiveness, illuminate methodological strengths and flaws, as well as reinforce conviction about susceptible populations.

High-latitude coral reef communities have been postulated as the first areas to undergo reorganisation under climate change. Tropicalisation has been identified in some high-latitude communities and is predicted in others, but it is unclear how the resident benthic taxa are affected. We conducted a long-term (2007–2016) assessment of changes to benthic community cover in relation to thermal stress duration on the Southeast Florida Reef Tract (SEFRT). Thermal stress events, both hot and cold, had acute (thermal stress duration affected benthic cover that year) and chronic (thermal stress duration affected benthic cover the following year) impacts on benthic cover. Chronic heat stress was associated with declines in cover of the reef-building coral families Acroporidae, Montastraeidae, Meandrinidae, Mussidae and Siderastreidae, which coupled with the absence of cold stress and rising annual temperatures boosted macroalgae cover. Cover of smaller, weedy coral families, Poritidae, Agariciidae and Astrocoeniidae, was either unaffected or positively related to heat stress duration and rising mean temperature. Thermal stress was related to spatiotemporal variations in benthic cover on the SEFRT, likely enhanced by local stressors, such as elevated nutrients and sedimentation. Coral and octocoral cover declined within four of six sub-regions, sponge cover increased in half of the sub-regions, and macroalgae cover increased in four sub-regions during the study. Under current conditions, increased macroalgae and weedy coral cover are anticipated to inhibit reef recovery. [ABSTRACT FROM AUTHOR]

The decline in coral reef health presents a complex management issue. While several causes of decline have been identified and are under continued study, it is often difficult to discern management actions necessary to address multiple near- and far-field stressors to these ecosystems. As a result, resource managers seek tools to improve the understanding of ecosystem condition and to develop management responses to reduce local and regional pressures in the wake of larger, global impacts. A research study conducted from 2010 to 2014 in southeast Florida, USA consisted of two objectives: (1) conduct a needs assessment survey with coral reef and marine resource managers to identify data needs and the preferred design and delivery of climate information; and (2) develop and evaluate prototype decision support tools. The needs assessment process was helpful for identifying the types of climate information managers would like to obtain to inform decision making and to specify the preferred format for the delivery of that information. Three prototype tools were evaluated by managers using pre/post surveys that included hands-on tutorials to explore the functionality of each. Manager responses were recorded using a five-point scale with 1 being No or Not Useful to 5 being Absolutely or Very Useful. The median responses rated the usefulness of the tools (4), if they would consider using the tool (4), and if they would recommend using the tool to other managers (4 or 5). The median response for increasing manager’s knowledge about climate impacts after completing a tutorial of each of the climate tools was a 3 (moderately useful). Of the managers surveyed in the pre/post-survey, all but one stated they believed they would use the decision support tools in the future with the single response due to wealth of data availability in their institution.

Dense Acropora cervicornis aggregations, or patches, have been documented within nearshore habitats in Southeast Florida (SE FL) despite close proximity to numerous anthropogenic stressors and subjection to frequent natural disturbance events. Limited information has been published concerning the distribution and abundance of A. cervicornis outside of these known dense patches. The first goal of this study was to conduct a spatially extensive and inclusive survey (9.78 km2) to determine whether A. cervicornis distribution in the nearshore habitat of SE FL was spatially uniform or clustered. The second goal was to investigate potential relationships between broad-scale seafloor topography and A. cervicornis abundance using high resolution bathymetric data. Acropora cervicornis was distributed throughout the study area, and the Getis-Ord Gi* statistic and Anselin Local Moran’s I spatial cluster analysis showed significant clustering along topographic features termed ridge crests. Significant clustering was further supported by the inverse distance weighted surface model. Ordinal logistic regression indicated 1) as distance from a ridge increases, odds of reduced A. cervicornis abundance increases; 2) as topographic elevation increases, odds of increased abundance increases; and 3) as mean depth increases, odds of increased abundance increases. This study provides detailed information on A. cervicornis distribution and abundance at a regional scale and supports modeling its distributions in similar habitats elsewhere throughout the western Atlantic and Caribbean. Acropora cervicornis is frequently observed and in areas an abundant species within the nearshore habitat along the SE FL portion of the Florida Reef Tract (FRT). This study provides a better understanding of local habitat associations thus facilitating appropriate management of the nearshore environment and species conservation. The portion of the FRT between Hillsboro and Port Everglades inlets should be considered for increased management and protection to reduce local stressors.

Sea level rise (SLR) imposes an increasing flooding hazard on low-lying coastal communities due to higher exposure to high-tide conditions and storm surge. Additional coastal flooding hazard arises due to reduced effectiveness of gravity-based drainage systems to drain rainwater during heavy rain events. Over the past decade, several coastal communities along the US Atlantic coast have experienced an increasing rate of flooding events. In this study, we focus on the increasing flooding hazard in Miami Beach, Florida, which has caused severe property damage and significant disruptions to daily life. We evaluate the flooding frequency and its causes by analyzing tide and rain gauge records, media reports, insurance claims, and photo records from Miami Beach acquired during 1998–2013. Our analysis indicates that significant changes in flooding frequency occurred after 2006, in which rain-induced events increased by 33% and tide-induced events increased by more than 400%. We also analyzed tide gauge records from Southeast Florida and detected a decadal-scale accelerating rates of SLR. The average pre-2006 rate is 3 ± 2 mm/yr, similar to the global long-term rate of SLR, whereas after 2006 the average rate of SLR in Southeast Florida rose to 9 ± 4 mm/yr. Our results suggest that engineering solutions to SLR should rely on regional SLR rate projections and not only on the commonly used global SLR projections. [ABSTRACT FROM AUTHOR]

Abstract: Water, sponge and coral samples were collected from stations impacted by a variety of pollution sources and screened for human enteric viruses as conservative markers for human sewage. While human enteroviruses and adenoviruses were not detected, noroviruses (NoV; human genogroups I and II) were detected in 31% of samples (especially in sponge tissue). Stations near inlets were the only ones to show multiple sample types positive for NoV. Fecal indicator bacteria and enteric viruses were further evaluated at multiple inlet stations on an outgoing tide. Greatest indicator concentrations and highest prevalence of viruses were found at the mouth of the inlet and offshore in the inlet plume. Results suggest that inlets moving large volumes of water into the coastal zone with tides may be an important source of fecal contaminants. Efforts to reduce run-off or unintended release of water into the Intracoastal Waterway may lower contaminants entering sensitive coastal areas. [Copyright &y& Elsevier]

During the 2004 hurricane season, Florida was hit by an unprecedented 4 hurricanes (Charley, Frances, Ivan, and Jeanne). The floodplain forest of the Loxahatchee River was impacted by both Hurricanes Frances and Jeanne. Hurricane Frances made landfall on September 5, 2004. Three weeks later, Hurricane Jeanne made landfall on September 25, 2004. Previously in 2003, floodplain vegetation studies were conducted along 10 vegetative belt transects on the tidal and riverine portions of the Northwest Fork of the Loxahatchee River and its major tributaries. In the summer and fall of 2005, canopy trees were reexamined along the 10 belt transects to assess hurricane damage. Comparisons were made between the 2003 survey of the canopy trees and the remaining canopy. In the tidal floodplains, tall white mangrove (Laguncularia racemosa) were heavily impacted, while shorter red mangrove (Rhizophora mangle) were only marginally impacted and defoliated. In the riverine floodplains, the heaviest damage occurred within bottomland hardwood communities with both red maple (Acer rubrum) and water hickory (Carya aquatic) impacted. Of the 1,694 canopy trees sampled, a 2.5% mortality rate occurred as a result of the storms. There is a concern these storms may provide an opportunity for the expansion of exotic pest plants within the floodplains. [ABSTRACT FROM AUTHOR]

Subtropical coastal sand dune ecosystems have been greatly altered by agricultural use, invasive exotic encroachment, urban development, and beach raking, rendering several plant species endangered or threatened. Restoration planning of this ecosystem will benefit from a comprehensive study on how environmental variables change across the coast- to-inland gradient of this ecosystem and it is therefore presented here. We also examined the relationship between the environmental characteristics and plant species composition across the gradient. We used the two largest extents of remaining dune ecosystem on the southeastern coast of Florida, where relatively intact populations of endangered species occur. Vegetation and environmental data were collected from 97 3 ×8 m plots in two sand dune parks along the coast-inland gradient. Soil moisture, most nutrients, cation exchange capacity, and organic matter accumulation increased with distance from the coast, whereas pH and salt spray decreased. The number of species per plot was higher at further distances from the coast at one site only, and higher woody cover was associated with less species diversity at the other site. Canonical correspondence analysis revealed the importance of P, Mg, Ca, pH, cation exchange capacity, organic matter, estimated nitrogen release, and salt spray in affecting vegetation zonation. We conclude that soil chemistry is the most determinant factor of community zonation in these subtropical dunes. Restoration planning should be site specific because of the differences in environmental factors between the two study sites. [ABSTRACT FROM AUTHOR]

This study is a multi-pronged description of a temperature-induced outbreak of white-band disease (WBD) that occurred in Acropora cervicornis off northern Miami Beach, Florida (USA), from July to October 2014. We describe the ecology of the disease and examine diseased corals using both histopathology and next-generation bacterial 16S gene sequencing, making it possible to better understand the effect this disease has on the coral holobiont, and to address some of the seeming contradictions among previous studies of WBD that employed either a purely histological or molecular approach. The outbreak began in July 2014, as sea surface temperatures reached 29°C, and peaked in mid-September, a month after the sea surface temperature maximum. The microscopic anatomy of apparently healthy portions of colonies displaying active disease signs appeared normal except for some tissue atrophy and dissociation of mesenterial filaments deep within the branch. Structural changes were more pronounced in visibly diseased fragments, with atrophy, necrosis, and lysing of surface and basal body wall and polyp structures at the tissue-loss margin. The only bacteria evident microscopically in both diseased and apparently healthy tissues with Giemsa staining was a Rickettsiales-like organism (RLO) occupying mucocytes. Sequencing also identified bacteria belonging to the order Rickettsiales in all fragments. When compared to apparently healthy fragments, diseased fragments had more diverse bacterial communities made up of many previously suggested potential primary pathogens and secondary (opportunistic) colonizers. Interactions between elevated seawater temperatures, the coral host, and pathogenic members of the diseased microbiome all contribute to the coral displaying signs of WBD.

This article presents yearly data for the period 2020-2060 on estimates for population growth and associated numbers of new and existing single-family detached homes to be fit or retrofit with rainwater harvesting (RWH) system equipment for lawn irrigation in order to continuously offset new water demand created by new residents in Broward and Palm Beach Counties, Florida. Annual data on financing costs for capital equipment and its replacement and savings in amounts of groundwater and associated water supply energy amounts and costs are also provided. The methods for determining and using the data presented in this article, along with related data, for the purpose of analyzing the feasibility of a widely-deployed residential rainwater harvesting (RWH) system in a heavily populated region in Southeast Florida are discussed in detail in Wurthmann [1]. The data presented here can be used by policy makers as a decision support tool for assessing broad outcomes related to population and single-family housing growth in Broward and Palm Beach Counties. They can also be used for more circumscribed outcomes related to developing implementation plans and assessing capital and financing costs and savings in water and energy amounts and costs for countywide RWH system installations. The data were derived from various expert projections, data from the U.S. Census Bureau, National Association of Home Builders (NAHB), Florida Department of Revenue and Property Tax, American Water Resources Association (AWRA), South Florida Water Management District (SFWMD), Electric Power Research Institute (EPRI), Energy Information Administration (EIA), and vendors of RWH system equipment, and customized calculations developed in Wurthmann [1]., (© 2019 The Author.)