Multiple Spatial Scale Assessment of Coral Reef and Hard-Bottom Community Structure in the Florida Keys National Marine Sanctuary

The zoning plan for the Florida Keys National Marine Sanctuary (FKNMS) established 23 relatively small no-fishing zones distributed mostly along the offshore reef tract in 1997. In 1999, a two-stage, stratified random sampling design based on the proportion of coral reef and hard-bottom types within the FKNMS was conducted. Our study focused on differences in coverage, density, and condition of benthic organisms with respect to habitat type, regional variations, and differences between no-fishing zones and reference sites at 80 locations spanning 200 km. Most variables exhibited significant spatial differences by habitat type or between individual no-fishing zones and reference sites (e.g. species richness, coral density, gorgonian density, and recruitment), although some regional differences were also apparent. Many of the differences among the no-fishing zones and reference sites reflect the placement of the zones in well-developed offshore reefs, and for many of the variables targeted, individual zones are as different from one another as from reference sites. These results emphasize the need to address spatial variations at multiple scales, and to consider a range of variables beyond common metrics such as coral cover

Density, Spatial Distribution and Size Structure of Sea Urchins in Florida Keys Coral Reef and Hard-Bottom Habitats

The 1983-84 Caribbean-wide mortality of the long-spined sea urchin Diadema antillarum Philippi was followed by a 2nd mortality event during 1991 in the Florida Keys. Pre-mortality sea urchin densities were up to 5 ind. m-2 and the large scale decline of D. antillarum is considered to be 1 factor affecting community dynamics of Florida Keys reefs. During 1999-2000, we surveyed 125 sites using a stratified random sampling design in shallow-water coral reef and hard-bottom habitats. Strip transects were sampled to assess density, habitat utilization and size structure patterns among habitat types, regional sectors and between fished and protected areas. Nearly 17 yr after the mass mortality, D. antillarum has not recovered to pre-1983 levels, with current densities no greater than 0.05 ind. m-2, and small test sizes (1 to 2 cm) dominate. Other sea urchins such as Eucidaris tribuloides (Lamarck) and Echinometra viridis Agassiz show density and habitat distribution patterns similar to historical observations

Population Status of Acropora Corals in the Florida Keys

Population declines of staghorn coral (Acropora cervicornis) and elkhorn coral (A. palmata) are often-cited examples of Caribbean reef change since the 1970s, due, in part, to disease and localized effects from storms and predation. Both corals were listed as threatened on the U.S. Endangered Species List based upon range-wide decline and poor recovery. A spatially intensive survey undertaken in the Florida Keys of Acropora corals quantified habitat distribution, colony abundance, size, and condition at 235 sites spanning over 200 km in 2007. A two-stage stratified sampling design using belt transects incorporated cross-shelf habitats and no-fishing management zones from \u3c 1 m to 15 m depth. A. cervicornis was widely distributed among sites and habitats and was particularly abundant on patch reefs, with up to 1.22 colonies/m2 and surface area coverage of 2%. A. palmata was abundant on shallow spur and groove reefs, with up to 1.25 colonies/m2 and surface area coverage of 25%. Although the prevalence of disease is relatively low, both species continue to suffer predation, as well as physical impacts from lost fishing gear. Predicting the future of these corals in Florida requires information about both their present-day ecology and geologic history in Florida

Stony Coral Species Diversity and Cover in the Florida Keys Using Design-Based Sampling

Large-scale sampling of stony coral species richness, species distribution, and cover was undertaken at 423 Florida Keys sites between Miami and SW of Key West during 2005 and 2007. A two-stage, stratified random sampling design employed belt transects to enumerate numbers of species and point-intercept surveys to quantify cover. The sampling design incorporated ten reef and hard-bottom habitats from \u3c 1 m to 27 m depth, as well as oceanographic regions and areas inside and outside of protected management zones. These data provide insights into the spatial extent and factors influencing stony coral biodiversity. For stony corals, a pool of ~50 taxa encompassing the Orders Milleporina and Scleractinia, including species and morphotypes, was recorded. Significant differences were found in species richness and cover among cross-shelf habitats, with great values on inner shelf margin patch reefs, followed by deeper fore-reef slope habitats that extended to the 27 m depth limit sampled. In contrast, the shallow fore-reef, especially in areas historically dominated by the branching coral Acropora palmata, yielded relatively low numbers of species and cover that are presently dominated by smaller, brooding corals such as Porites astreoides and Favia fragum

Benthic Habitat Mapping in the Tortugas Region, Florida

Concern about declining trends in coral reef habitats and reef fish stocks in the Florida Keys contributed to the implementation of a network of no-take marine protected areas in 1997. In support of the efforts of the Dry Tortugas National Park and Florida Keys National Marine Sanctuary to implement additional no-take areas in the Tortugas region in 2001, we expanded the scale of our fisheries independent monitoring program for coral reef fishes in the region. To provide a foundation for the habitat-based, stratified random sampling design of the program, we created a digital benthic habitat map of coral reef and hard-bottom habitats in a geographic information system by synthesizing data from bathymetric surveys, side-scan sonar imagery, aerial photogrammetry, existing habitat maps, and in situ visual surveys. Existing habitat maps prior to 1999 were limited to shallow-water (\u3c 20 m depth) soft-sediment, coral reef, and hard-bottom habitats within Dry Tortugas National Park and did not include deeper areas such as the Tortugas Bank, now partially contained within no-take marine protected area boundaries. From diver observations made during the 1999 survey, we developed a classification scheme based on habitat relief and patchiness to describe nine hard-bottom and coral reef habitats encountered from 1-33 m depth. We provide estimates of area by habitat type for no-take marine protected areas in the Tortugas region. Updated information on the spatial distribution and characteristics of benthic habitats will be used to guide future monitoring, assessment, and management activities in the region. Significant data gaps still exist for the western area of the Florida Keys National Marine Sanctuary and are a priority for future research

Pseudomonas aeruginosa mutants defective in glucose uptake have pleiotropic phenotype and altered virulence in non-mammal infection models

Pseudomonas spp. are endowed with a complex pathway for glucose uptake that relies on multiple transporters. In this work we report the construction and characterization of Pseudomonas aeruginosa single and multiple mutants with unmarked deletions of genes encoding outer membrane (OM) and inner membrane (IM) proteins involved in glucose uptake. We found that a triple \u394gltKGF \u394gntP \u394kguT mutant lacking all known IM transporters (named GUN for Glucose Uptake Null) is unable to grow on glucose as unique carbon source. More than 500 genes controlling both metabolic functions and virulence traits show differential expression in GUN relative to the parental strain. Consistent with transcriptomic data, the GUN mutant displays a pleiotropic phenotype. Notably, the genome-wide transcriptional profile and most phenotypic traits differ between the GUN mutant and the wild type strain irrespective of the presence of glucose, suggesting that the investigated genes may have additional roles besides glucose transport. Finally, mutants carrying single or multiple deletions in the glucose uptake genes showed attenuated virulence relative to the wild type strain in Galleria mellonella, but not in Caenorhabditis elegans infection model, supporting the notion that metabolic functions may deeply impact P. aeruginosa adaptation to specific environments found inside the host

Spatial Dynamics of Coral Populations in the Florida Keys

Coral reef degradation has been observed worldwide over the past few decades resulting in significant decreases in coral cover and abundance. However, there has not been a clear framework established to address the crucial need for more sophisticated understanding of the fundamental ecology of corals and their response to environmental stressors. Development of a quantitative approach to coral population ecology that utilizes formal, well established principles of fishery systems science offers a new framework to address these issues. The goal of this dissertation is to establish a quantitative foundation for assessment of coral reefs by developing some essential ecological and population-dynamic components of a size-structured demographic model for coral populations of the Florida Keys coral reef ecosystem. The objective provides the potential to build a quantitative systems science framework for coral populations. A two-stage stratified random sampling design was implemented during two separate survey periods to assess coral populations. Results include precise estimates of adult (\u3e 4 cm) population abundance for several coral species by spatially partitioning abundance and variance into species-relevant reef habitat types. Adult size structure and juvenile abundance were used to evaluate individual coral populations and infer spatial variation in recruitment, growth and survival across habitat types. Partial mortality was characterized in terms of surface area, prevalence, and size-relationships. The development of some ecological and population-dynamic components of a size-structured demographic model for coral populations demonstrates the statistical framework and metrics required for monitoring and assessment of coral reef ecosystems to meet the pressing needs of conservation of coral reef ecosystems specifically in Florida, and throughout the Caribbean and Pacific in general

Impacts of Lost Fishing Gear on Coral Reef Sessile Invertebrates in the Florida Keys National Marine Sanctuary

The Florida Keys coral reef ecosystem supports multimillion-dollar commercial and recreational fisheries. The ecological effects caused by fishing gear that is lost when cut or broken after snagging on the bottom is a growing concern to managers and scientists. Few data exist, however, to assess the impacts of lost fishing gear to benthic organisms and habitat structure. In this study, 63 offshore coral reef and hard-bottom sites were surveyed during 2001 to quantify the impacts of lost fishing gear to coral reef sessile invertebrates. Lost hook-and-line fishing gear accounted for 87% of all debris (N=298 incidences) encountered and was responsible for 84% of the 321 documented impacts to sponges and benthic cnidarians, predominantly consisting of tissue abrasion causing partial individual or colony mortality. Branching gorgonians (Octocorallia) were the most frequently affected (56%), followed by milleporid hydrocorals (19%) and sponges (13%). Factors affecting the impacts of lost fishing gear include sessile invertebrate density, the density of lost fishing gear, and gear length. While lost hook-and-line fishing gear is ubiquitous in the Florida Keys, less than 0.2% of the available milleporid hydrocorals, stony corals, and gorgonians in the habitats studied are adversely affected in terms of colony abrasions and partial mortality