A throw-trap survey of the nearshore flora and fauna of Biscayne Bay, Florida, USA, was conducted in the shallow open-water area along the western shoreline of South Biscayne Bay (Matheson Hammock to Turkey Point) in 2005, in order to gain an understanding of fish and invertebrate species structure and assemblages of this habitat. The rainwater killifish (Lucania parva), was the most abundant species in our samples and was examined in relation to biotic and abiotic factors that might influence the distribution of this species. Individual fish were counted, weighed, and measured, while salinity, temperature, and depth were recorded at the site, and the benthic habitat was quantified on site using the Braun-Blanquet method. This survey yielded 1,990 individuals over the course of two sampling seasons that were designated as wet (August) and dry (February) seasons. Forty-seven sites were sampled each season. A length-weight relationship was generated, and density, biomass, and other abundance indices were generated. The density of L. parva at our sites was much higher than other reported densities for this species, and there was a clear seasonal trend in the abundance of rainwater killifish, with twice as many individuals in the wet season. The proportion of juveniles in the samples suggested that reproduction occurred at least twice a year, prior to both sampling periods. Salinity and density of L. parva varied inversely. Using a model developed by Diego Lirman (2007), segments of the mainland shoreline were identified as clusters having similar salinity regimes. Density and size composition varied significantly between salinity clusters. More juveniles were observed in the wet season and in cluster 2, defined by its moderate salinity and relatively low salinity variability. Significantly fewer killifish were observed within cluster 3, a cluster characterized by a high amount of canal discharge and salinity variability. Canopy height of the seagrass was the most significant factor affecting the abundance of L. parva. Coverage of Thalassia testudinum and mixed algae also appeared to play a role in the abundance of this species. Together, canopy height and salinity formed the strongest relationship with L. parva abundance. Results suggest that salinity and certain habitat variables may be accurate predictors of the abundance and distribution of this species along the mainland shoreline of Biscayne Bay. There are a number or regulations already in place that protect the mangrove habitat in which L. parva resides. Fewer regulations address critical seagrass habitats. The Comprehensive Everglades Restoration Plan aims to correct decades of destructive modifications to the hydrology of South Florida by creating a more natural sheetflow and minimizing point source freshwater discharge into Biscayne Bay. These alterations are likely to have consequences for the flora and fauna of the Bay, but will ultimately have a positive impact on many species that reside in Biscayne Bay, including the rainwater killifish.

Mangroves and seagrass beds serve as essential fish habitat for many economically- and ecologically-valuable species. Depending on their location, these shallow-water habitats are often characterized by substantial fluctuation in salinity levels, which can represent a source of osmoregulatory stress for associated organisms. In South Florida, one of the most important fish species that utilizes these habitats is the gray snapper (Lutjanus griseus). Although this species constitutes a significant portion of the region?s total recreational fishery harvest, the effects of salinity on its distribution, physiology and behavior remain poorly understood. The main goal of this thesis was then to investigate the ecophysiological basis of habitat selection by the gray snapper. Specific objectives include to: (1) examine patterns of distribution and abundance across gradients in environmental salinity; (2) measure physiological status and responses to controlled salinity challenges and; (3) conduct behavioral trials to examine for salinity preferenda (if any). To begin investigating if salinity could be a primary factor structuring the gray snapper assemblages, I examined empirical data collected from Biscayne Bay to test the null hypothesis that gray snapper abundances were evenly distributed along the full salinity range at which samples have been collected. Using the delta approach, three abundance metrics (frequency of occurrence, concentration and delta density) were used as an index for the distribution and abundance of this species. Results indicated that abundance patterns for the smaller gray snapper were consistent with a strategy of reducing osmoregulatory costs by selecting intermediate salinities. However, corresponding abundance patterns for subadult gray snapper were inconsistent with this strategy of minimizing energetic costs, suggesting that this life stage may be indifferent to the range of salinities at which they were observed. These patterns helped developed further hypotheses regarding the ecophysiology of juvenile and subadult gray snapper, the latter of which was then tested via laboratory experiments. Subsequently, I challenged fish in the laboratory with six different salinity treatments (0, 5, 30, 50, 60 and 70ppt, including control) for 192 consecutive hours and collected blood samples at different time points. Results indicated that physiological stress to salinity changes is unlikely to occur at a salinity range of 5 to 50 ppt. At salinities of 0 and 60 ppt transient significant changes in plasma osmolality and/or blood haematocrit were observed, but were corrected after an initial adjustment period of approximately 96 hours. At the highest salinity treatment (70 ppt), a constant osmolality could not be maintained, resulting in death for all fish within 48 hours of exposure. Overall, these findings demonstrate the strong euryhalinity and extraordinary tolerance of this species to both extreme hypo- and hypersaline environments. Finally, I investigated the salinity preference and effects on swimming behavior of the gray snapper in an automated salinity choice shuttlebox via 48-hr trials. In general, gray snapper tested displayed either one of two distinctively different salinity preferences. Half of gray snappers displayed a salinity preference in the range of 9-15 ppt, whereas the other half displayed a salinity preference in the range of 19-23 ppt. Recorded swimming speeds in all fish tested reflected a significant, but weak negative linear relationship with salinity during both time periods of the day (light and dark); however, gray snapper were usually most active during the dark period across all salinities. Overall, these findings reveal that gray snapper prefer slightly hyperosmotic salinities that may minimize the physiological costs of osmoregulation compared to extreme salinities.

Bottlenose dolphins (Tursiops truncatus) are large-bodied predators that are locally abundant in the coastal Everglades. Because of their potential to exert strong top-down effects on their communities, it is important to understand how spatiotemporal variation in biotic and abiotic factors affects the abundance and behavior of dolphins. This study combined two years of transect surveys with photographic identification methods to assess spatiotemporal variation in the abundance and group sizes of bottlenose dolphins across four large regions of the coastal Everglades including the Shark and Harney Rivers, Whitewater Bay, and coastal oceans of the Gulf of Mexico and Florida Bay. Dolphin abundance was similar across wet and dry seasons, except in river habitats where abundances were higher during the dry season. Group sizes were largest in Florida Bay and open water. Dolphins may be relatively resilient to abiotic changes in the coastal Everglades, with the possible exception of river habitats.

Approved for public release; distribution is unlimited / The United States has spent over $2 billion during the last six years to reconstruct and stabilize Afghanistan through the Commander's Emergency Response Program (CERP). This effort is only one of several simultaneous programs attempting to stabilize Afghanistan using approaches including providing humanitarian aid, education, government and security reform, and construction. Construction often involves simple infrastructure development with tangible benefits including increased access, growing commerce and better security. Construction projects can also employ the local population and, if done correctly, develop a sense of community and social capital. What causes construction projects to miss the mark failing to result in creating a stable community? This research compares four different construction programs including CERP, National Solidarity Program (NSP), United States Agency for International Development (USAID), and Provincial Reconstruction Teams (PRT) to determine their potential impact on Afghan stability. It uses a combination of statistical regression, correlation, geospatial and temporal analysis to compare completed construction with recorded SIGACTs (Significant Acts) reported by U.S. forces and NGOs. The results imply that the identified stabilization programs are not using construction effectively to create social capital and stability.