Sex determination in leatherback sea turtles is directed primarily by the temperatures a clutch experiences during the middle third of development. Warmer temperatures tend to produce females will cooler temperatures yield males. Nest temperatures can vary spatially and temporally. During the 2010 and 2011 nesting seasons, this study estimated the hatchling sex ratio of leatherback sea turtles on Sandy Point National Wildlife Refuge (SPNWR), St. Croix, U.S. Virgin Islands. I measured sand temperatures from May- August and across the spatial range of leatherback nesting habitat. I spatially interpolated those temperatures to create maps that predicted temperatures for all nests incubating on SPWNR. Nest temperatures were also directly measured and compared with predicted nest temperatures to validate the prediction model. Sexes of dead-in-nest hatchlings and full term embryos were used to confirm the sex-temperature response. The model showed that microclimatic variation likely impacts the production of both sexes on SPNWR. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2013.

The tropical fire ant, Solenopsis geminata is a New World species with a wide native range including South America as well as several Caribbean islands. The red imported fire ant, Solenopsis invicta is native to parts of South America. Both species are known for preying on sea turtles’ eggs and hatchlings. The objectives of this thesis research were to conduct follow-up and baseline ant species distribution surveys on four sea turtle nesting beaches in St. Croix, U. S. Virgin Islands. Tuna baits were set out at beaches; specimens were collected, frozen, preserved then identified. Results show that there was a significant change in the fire ants’ distribution at Sandy Point National Wildlife Refuge (SPNWR) while none were found at Jack Bay. Fire ants were also present on the other two baseline surveyed nesting beaches. The displacement of S. geminata by S. invicta was observed at SPNWR, which also was presumed by previous surveys. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Greater Sage-Grouse (Centrocercus urophasianus) have experienced declines throughout their range over the last 50 years. Long-term declines in sage-grouse abundance in Nevada and Oregon have been attributed to reduced productivity. From 1995-1997, sage-grouse production on Sheldon National Wildlife Refuge (SNWR), Nevada was greater compared to Hart Mountain National Antelope Refuge (HMNAR), Oregon. Specific causes for the difference were unknown. Thus, the objectives were to: 1) Determine sage-grouse breeding season habitat use (especially with regard to wildfire) on SNWR; 2) Evaluate reproductive parameters to discern differences between SNWR and HMNAR; 3) Compare habitat components which may relate to differences in sage-grouse reproductive success on SNWR and HMNAR; and 4) Establish hematological and serum chemistry reference ranges for sage-grouse hens to assess physiological condition. Cover type was important in selection of nest sites at SNWR; however, nest cover did not affect nesting success and nest-site selection was not related to experience. Vegetative characteristics at successful nest sites were similar to unsuccessful nests but nest sites had greater amounts of tall residual grass (���18 cm) and medium height shrub cover (40-80 cm) than at random sites. Broods used areas with greater forb cover than random sites, indicating use was influenced by availability of forbs. Plant communities in wildfire and associated control sites did not differ appreciably in species composition. Although burning had little stimulatory effect on total forb cover 10-12 years post-burn, alteration of the sagebrush community did not limit sage-grouse use for successful nesting and brood-rearing. Fire did not negatively impact arthropod abundance. Differences in habitat use and sage-grouse productivity between SNWR and HMNAR may be related to differences in forb availability. Forb cover was greater at HMNAR than at SNWR for all cover types. Correspondingly, home range size for sage-grouse broods was greater on SNWR than at HMNAR. Nutrient analysis of forbs indicated higher crude protein, potassium, and magnesium levels at HMNAR than at SNWR; however, these nutrients are not likely to be deficient in most sage-grouse diets. Thus sagebrush-steppe communities supporting these forbs likely meet the dietary nutritional requirements of sage-grouse. Although blood calcium and uric acid levels were greater in sage-grouse hens on HMNAR than at SNWR, differences were attributed to capture date. Furthermore, physiological condition did not affect a hen's ability to nest successfully, nor was condition related to a hen's ability to recruit chicks to 1 August. Causes of sage-grouse decline are varied, but ultimately they are habitat based. Comparisons of reproductive parameters and habitat evaluations, combined with sage-grouse physiology data, may provide insight into habitat differences between study areas not previously recognized. Land management practices (e.g., prescribed fire) which recast the balance of native herbaceous species in degraded big sagebrush communities, may be necessary in the restoration of sagebrush-steppe ecosystems, and ultimately, the recovery of sage-grouse populations. / Graduation date: 2003

This study uses the storm surge sediment beds deposited by Hurricanes Audrey (1957), Carla (1961), Rita (2005) and Ike (2008) to investigate spatial and temporal changes in sedimentation rates on the McFaddin National Wildlife Refuge in Southeast Texas. Fourteen sediment cores were collected along a transect extending from 90 to 1230 meters inland from the Gulf Coast. Storm-surge-deposited sediment beds were identified by texture, organic content, carbonate content, the presence of marine microfossils, and Cesium-137 dating. The hurricane-derived sediment beds are marker horizons that facilitate assessment of marsh sedimentation rates from nearshore to inland locations as well as over decadal to annual timescales. Near the shore, on a Hurricane Ike washover fan, where hurricane-derived sedimentation has increased elevation by up to 0.68 m since 2005, there was no measurable marsh sedimentation in the period 2008-2014. Farther inland, at lower elevations, sedimentation for the period 2008-2014 averaged 0.36 cm per year. The reduction in sedimentation in the period 2008-2014 on the nearshore part of the marsh is likely due to reduced flooding in response to increased elevation from hurricane storm surge sediment deposition. These results provide valuable knowledge about the sedimentary response of coastal marshes subject to storm surge deposition and useful guidance to public policy aimed at combating the effects of sea level rise on coastal marshes along the Gulf of Mexico.

Using quantitative content analysis, this study explores social movement (SM) framing in commercial news media -- by comparing how leading newspapers covered prominent protest occupations in 2011 and 2016. More than other SMs, anti-systemic protests like the 2011 Occupy Wall Street (OWS) and the 2016 Malheur Refuge Occupation (MRO) only have partial frame-setting agency, raising a broad theory question (to inform the research questions below): If SMs and media relate as interacting systems, are protest news frames more movement- or more media- driven; and do media not just enable but also constrain SMs? With the movement-media theory question above, the study design adapts media opportunity structure (MOS) to model a hierarchy of influences on news coverage of ideologically opposed or "distant twin" OWS and MRO, as 40- to 60-day protest occupations. The focused research question -- exploring media's constraining potential -- asks if commercial news framing of collective action: i) commercially frames or "sells" even anti-corporate protest; or ii) instead marginalizes or neutralizes such protest? Coverage from three top national or state newspapers (The New York Times, USA Today, and The Oregonian) was analyzed randomly from all protest stories during the occupations. Sampled time periods in 2011 and 2016, during actual encampments/ occupations in Portland, OR and New York City (OWS) and in Malheur National Wildlife Refuge, Oregon (MRO), also correspond with transitional years in print news. The inductive-based comparative results, from 15 coding dimensions for news framing of collective action, dispersed passivity, and commercially-framed activism, showed some evidence for the "selling protest" question. And the compiled summary Framing Advantages and Disadvantages yield this study's key finding: Although anti-corporate OWS was far larger, with more widespread media coverage, the comparative overall media frame for the small, remote, anti-government MRO was far more potent and resonant. Comparing media-and-movement framing of these distant twin 40-day protest occupations finds some support for the "selling (or underselling) protest" question. This comparative frame analysis helps bridge micro- and macro-theory levels, addressing an enduring dual gap in movement-media research literature -- to yield insight on SMs' and media's respective roles in protest news framing and then identify potential mechanisms for future research.

This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments.

Conflicts between local people and protected areas can undermine conservation goals. This study explores perceptions towards Vieques National Wildlife Refuge (VNWR), a complex former military site containing a combination of high ecological value along with an array of unexploded ordnances. The purpose of this research is to evaluate how residents perceive VNWR and elucidate conflicts associated with former and current uses of the wildlife refuge. Here, I interviewed 235 residents of Vieques Island, Puerto Rico using semi-structured surveys and 33 key informants representing various stakeholder groups to assess attitudes toward VNWR. A combination of factors influencing attitudes about VNWR included socio-economic status and misconceptions about management. Overall, residents did not express strong attitudes. However, older individuals and those living longer on Vieques generally had poorer attitudes than others. Among the most common reasons for expressing discontent were the restrictive regulations regarding access to VNWR and the limitations on resource extraction.

Among exotic species that are capable of invading, establishing, and reaching pest status, few pose the range of impacts to biotic (e.g., competition with native species, predation, herbivory, introduction of other exotics) and abiotic (e.g., soil, hydrology) ecosystem components that can be attributed to the wild pig (Sus scrofa). Despite the presence of wild pigs throughout the southeastern United States for centuries, new invasions continue to occur in previously uninhabited and often under-investigated landscapes, including bottomland and upland forests. The recent invasion of the Sam D. Hamilton Noxubee National Wildlife Refuge (hereafter, NNWR) in east-central Mississippi represents an opportunity to understand not only a species invasion during an emergent stage, but also to improve and better inform the methods used to combat such species in forested landscapes. In recent years, the United States Fish and Wildlife Service has begun to observe direct impacts to this ecologically sensitive area which is critically important to not only migratory waterfowl but also a multitude of other faunal (e.g., amphibians, reptiles, and avian species of concern) and floral species. As a result, identifying wild pig spatial distributions (e.g., movements, occurrence) and estimating wild pig abundance in the NNWR have each increased in priority. My dissertation research has facilitated an improved understanding of how wild pigs have invaded this novel landscape through investigations of space use, abundance, and occurrence, and will better inform and improve efficiency of future monitoring and control efforts. Understanding how this wild pig invasion relates to the NNWR landscape may also provide information that can be used to better address wild pig invasions of similar landscapes, with added value for those that are similarly characterized by sensitive ecosystems (i.e., managed for migratory waterfowl, species of concern) that are currently faced with this emerging threat. Given the universality of many of the methodological approaches undertaken in this effort, this multifaceted investigation also provides broader implications for other landscapes and exotic species of interest.

Snowy plovers (Charadrius nivosus) are small, ground-nesting shorebirds that are a species of conservation concern throughout North America. Despite increased efforts to understand factors contributing to the decline of snowy plover, little is known about habitat selection and breeding ecology of snowy plover for the large population found in the Great Basin. We tested hypotheses concerning the occupancy and nesting success of snowy plover. First, we identified factors influencing snowy plover nest survival at Great Salt Lake, Utah. We hypothesized that snowy plover would demonstrate differences in nest survival rates across years due to differences in habitat characteristics, predator abundance, human influence, resource availability, and fluctuating water levels. We conducted nest surveys at five sites along the Great Salt Lake to locate new nests or monitor known nests until nest fate was determined. We found 608 nests between 2003, 2005-2010, and 2012. The most common cause of nest failure was predation, followed by weather, abandonment, and trampling. Nest survival estimates ranged from 4.6 -- 46.4% with considerable yearly variation. There was no correlation between researcher activity (visits to nests and trapping of adults) and nest survival. Nests in close proximity to roads had lower survival than nests far from roads. Nests located on barren mudflats also had lower survival than nests in vegetated areas or near debris. We found that nests had a higher probability of survival as they increased in incubation stage. Because nesting areas around the Great Salt Lake host some of the largest concentrations of breeding snowy plover in North America, we suggest that managers consider measures to maintain suitable nesting habitat for snowy plover. Second, we determined factors affecting snowy plover occupancy and detection probabilities in western Utah between 2011 and 2012. We hypothesized that snowy plover would be associated with spring water flows and sparsely vegetated salt flats. We made repeated visits to randomly selected survey plots recording the number of snowy plover adults and habitat characteristics within each plot. We modeled the relationship between snowy plover detection probability and habitat and environmental characteristics. The detection probability was 77% (95% CI = 64 -- 86%) and did not vary by year. There was a positive relationship between ambient temperature and detection probability. Next, we modeled the relationship between snowy plover occupancy and individual habitat characteristics including distance to water, distance to roads, land cover types, and vegetative characteristics. Snowy plover occupancy did not vary by year and was estimated at 12% (95% CI = 7 -- 21%). Occupancy was best predicted by close proximity to water, playa land cover, and minimal shrub cover. We used habitat characteristics that best predicted snowy plover occupancy to generate a predictive habitat model that can help prioritize future snowy plover surveys and guide conservation efforts.

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