abstract: For animals that experience annual cycles of gonad development, the seasonal timing (phenology) of gonad growth is a major adaptation to local environmental conditions. To optimally time seasonal gonad growth, animals use environmental cues that forecast future conditions. The availability of food is one such environmental cue. Although the importance of food availability has been appreciated for decades, the physiological mechanisms underlying the modulation of seasonal gonad growth by this environmental factor remain poorly understood. Urbanization is characterized by profound environmental changes, and urban animals must adjust to an environment vastly different from that of their non-urban conspecifics. Evidence suggests that birds adjust to urban areas by advancing the timing of seasonal breeding and gonad development, compared to their non-urban conspecifics. A leading hypothesis to account for this phenomenon is that food availability is elevated in urban areas, which improves the energetic status of urban birds and enables them to initiate gonad development earlier than their non-urban conspecifics. However, this hypothesis remains largely untested. My dissertation dovetailed comparative studies and experimental approaches conducted in field and captive settings to examine the physiological mechanisms by which food availability modulates gonad growth and to investigate whether elevated food availability in urban areas advances the phenology of gonad growth in urban birds. My captive study demonstrated that energetic status modulates reproductive hormone secretion, but not gonad growth. By contrast, free-ranging urban and non-urban birds did not differ in energetic status or plasma levels of reproductive hormones either in years in which urban birds had advanced phenology of gonad growth or in a year that had no habitat-related disparity in seasonal gonad growth. Therefore, my dissertation provides no support for the hypothesis that urban birds begin seasonal gonad growth because they are in better energetic status and increase the secretion of reproductive hormones earlier than non-urban birds. My studies do suggest, however, that the phenology of key food items and the endocrine responsiveness of the reproductive system may contribute to habitat-related disparities in the phenology of gonad growth. / Dissertation/Thesis / Doctoral Dissertation Biology 2014

The City of Denton, located in a semi-arid region of Texas, has over 200 manmade ponds within its city limits. Many of these ponds, located in densely populated areas, are engineered to control storm water runoff. There is a general lack of recognition of the value these waters contribute to regional biodiversity and as greenspaces. This study, conducted in Denton, is monitoring habitat variables and macroinvertebrate diversity in a series of ponds selected to represent a gradient of urban influences. The objective of this study is to identify the variables associated with the highest diversity. Using drone imagery and a meter square box sampler, the quantitative approach allowed for delineation of three habitat types and area. The macroinvertebrates where identified to the genus level which allowed for higher resolution and resulted in stronger comparisons of the communities and conditions of the ponds. Taxa richness was positively correlated to pond size and trees along shoreline and negatively associated with average depth. Overall, submerged vegetation supported highest diversity and abundance, especially genera of Chironomidae (Diptera). Conductivity was associated with urban influences and the most urban influenced pond had the lowest taxa richness, but also reduced habitat area. Results of this study conclude that these stormwater ponds benefit to the ecology of the city and provide beautiful, green spaces. If managed correctly, these systems can be incorporated into sustainable development in the future of the City of Denton.

City greenspaces are often considered as refuges for wildlife living in the urban area.At the same time, the original function of greenspaces is providing relaxing places forpeople. So, to provide suitable area for both humans and wildlife in the city, it isimportant to learn about the preference to city greenspace design by humans and birds.In this study, I selected 45 city greenspaces from Stockholm and Uppsala, Sweden, andused opportunistic citizen science bird records, environmental parameters ofgreenspaces analyzed by GIS and an online social survey to compare the preference ofbirds (using bird diversity as a proxy for preference) and humans living in urban areawith respect to certain environmental parameters of city greenspaces. I found that bothpeople and birds prefer greenspaces with large area, and some water area in or aroundgreenspace. I also found some conflicting preferences in that people more preferredgreenspaces near the city center but bird diversity was higher in greenspaces fartherfrom the city center. These results might bring new mind for urban ecology researchand ecofriendly city greenspace design. Greenspaces with larger area and water areawould be preferred by both people and birds.

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Driven by individual influences such as beliefs, attitudes, personal norms, and abilities, as well as by social influences like community norms, mandates, and the market, suburban homeowners are motivated to select and maintain a turf grass landscape. In many areas of Florida, effective suburban lawn maintenance requires regular inputs of nitrogenous fertilizer, some of which is lost to the environment, contributing to water quality degradation and ecosystem dysfunction. Reducing nitrogen inputs to aquatic systems requires a better understanding of the links between residential landscape management and the potential for fertilizer loss. This dissertation examines the linkages between the human behaviors contributing nitrogen to the suburban landscape and the resulting environmental impacts. Framed in socio-psychological theory and social marketing research, the outcomes of this dissertation contribute much needed information to the growing realm of interdisciplinary science that expands integrative theory, develops mixed methods, utilizes spatial and temporal analyses, and conducts actionable research. Using a suite of research tools, this dissertation examines relevant urban ecology questions:  What behavioral and socio-demographic variables most strongly influence individual residential landscape design and management practices?  What types of communities are more likely to contribute more nitrogen inputs?  What social constraints prevent homeowners from implementing a more sustainable residential landscape? iv  What outcome measures can be used to evaluate the environmental impact associated with landscape maintenance behaviors? Social and environmental data were collected over five years from three distinct projects to advise environmental marketing strategies and targeted communications. The research questions provided important information for water quality stakeholders and environmental marketers to prioritize strategies and target audiences based on the power of forces that are influencing landscaping behaviors. The research drew on the methods of urban ecology to understand nutrient dynamics by spatially integrating social and environmental data. It used social-psychology theory to define influences that can motivate or deter landscape management behaviors and preferences. It applied the methods of social marketing to advise implementation strategies. Completing this research involved ethnographic, social survey, and environmental quality data collection. Suburban homeowners were recruited as research participants to collect important qualitative information about individual and social forces of suburban landscape management and the perceptions of environmentally-friendly landscaping. Questions were developed to operationalize the dimensions of individual and social influences and quantitative data were collected at two different scales, regional and statewide. Homeowners were defined in terms of their polluting potential, influences and mandates as well as their potential for adopting a more sustainable landscape. The research mapped behavioral and environmental data to understand human-ecosystem linkages and recommended environmental quality indicators to continue building future outcomes. This dissertation research was conducted in three distinct projects. v The Landscape Exchange project collected telephone survey data, interview data, and ethnographic information from project participants for three years in a subdivision in southwest Florida. In the Wekiva Basin of Central Florida, the Land-water Connection (LWC) project studied sources of nitrogen by examining the linkages between human behaviors, community land use patterns, and environmental quality. In the LWC project, patch dynamics of a suburbanizing watershed were mapped to link residential fertilizer frequency with water resource impacts. By collecting socio-economic information key to understanding the households and neighborhoods within the watershed, LWC attempted to better understand and characterize polluting potential and impact. This investigation of the human-ecosystem connection provided valuable insight to the potential source contributed by residential landscape management while demonstrating a tool for visualizing human-environment interactions. Integrating data and understanding processes that are being carried out at different spatial and temporal scales requires research that crosses interdisciplinary boundaries and extends beyond simple models to understand complex causal relationships (Young et al 2006). The LWC project integrated socio-demographic data like housing age and property values, household and lifestyle behaviors, and individual application rates with environmental data such as soil nutrients and groundwater NO3 - concentrations. Results demonstrated that significant relationships existed between structural features like Homeowners Associations (HOA) and golf courses and high fertilizer frequency, but that these areas did not consistently show patterns of elevated nitrogen concentrations in ground and surface water. vi Confounding geophysical features, limited data availability, and a temporal lag between land-based fertilizer activity and groundwater nitrogen concentrations are likely. In the Predicting Maintenance Intensity (PMI) project, I collected statewide survey data from Florida homeowners and used multivariate analyses to determine if the same variables that predicted landscape maintenance intensity also influenced the odds of adopting an environmentally-friendly landscape (EFL). The purpose was to see how landscape maintenance and EFL adoption related and which human psychological or socio-economic variables predicted them. I used the framework of the Theory of Planned Behavior and Normative Action Theory to measure the extent that individual beliefs or community influences predicted landscape maintenance intensity. Although most of the alternative hypotheses that I posed in the research were significantly related to landscape maintenance intensity and EFL adoption in the predicted direction, the findings were somewhat unexpected. This was particularly the case when comparing household’s position on environmentally-friendly landscaping (EFL) adoption and landscape maintenance intensity. I found that those who adopted EFL practices had similar landscape maintenance intensity scores as those who did not intend to ever change their landscape practices and that those who intended to do more EFL had the highest landscape maintenance intensity score. This indicated that landscape maintenance intensity was a useful measure of product inputs but did little to explain individual attitudes about EFL adoption. Similar to the findings of the Land-Water Connection in Wekiva referenced previously, the statewide PMI project also found that community norms, living in a HOA governed community and household income were significant positive predictors of high vii landscape maintenance and that environmental consciousness, awareness of consequences, and house age were significant negative predictors. Environmental consciousness and enjoying gardening significantly increased the odds of currently practicing or intending to practice EFL relative to never changing their landscape, but community norms only significantly influenced the likelihood to intend to do more EFL. Another interesting finding of this dissertation was the differences of predictive powers of variables over scales. For example, the individual scale versus the community scale of influence. EFL Adoption was related more to individual characteristics such as personal norms, attitudes about the garden, and awareness of consequences while landscape maintenance intensity was more influenced by structural differences like who was responsible for maintenance and socio-demographics like house age and income were strongly significant and community norms. The findings of this dissertation supported the concept of lawn anxiety described by Robbins (2007), regarding those who are aware of the environmental consequences, but still applied lawn care products. It would be interesting to explore the relationships further to understand why those who are environmentally aware are motivated to high maintenance regardless. From these results, it appears they are influenced by their community norms and HOA mandates. More investigation of the human dimensions of the suburban landscape is warranted. Further research on human life-history measures, perceived behavioral controls and normative influences of those who adopt alternative landscapes would help guide communications. Understanding more specifically what mechanisms are needed to enable a societal change to a sustainable landscape requires further exploration of the motives and barriers that will prevent it from happening. viii Further research is also needed to better understand suburban nitrogen system dynamics. Studies that focus at the community scale should be conducted to apply and trace residential fertilizes from the yard to the street and into aquatic systems. The use of labeled nitrogen fertilizer can be used identify fertilizer from background nitrogen. Lastly, land use planning and development must seek to rebalance the scale that promotes both environmental protection and economic growth back toward environmental protection. It has been too long tipped in favor of development pressure and short-term economic growth to the demise of our aquatic systems.

Individual organisms often use cues from their natural environments to determine many behavioral and life-history "decisions." These "decisions" are usually adaptive, i.e. a response to selection, because the environmental cues on which they are based reliably correlate with increased fitness over time. When the selected behavioral response to a natural cue no longer provides a fitness benefit, then selection for a new response may occur but individuals maintaining the previously selected response may suffer reduced survival and reproduction. Especially in human-modified landscapes individuals making a maladaptive behavioral or life-history choice based on those formerly reliable environmental cues may be faced with an "evolutionary trap". In urban, or suburban, environments many factors have been altered in ways that could lead to evolutionary traps. Inappropriate behavioral responses by many individuals could lead to reduced demographic performance of urban populations relative to their wildland counterparts and to the decline of entire urban populations. In birds, maladaptive patterns of nest provisioning or vigilance may occur (a) when human-provided adult foods are easier to feed young because they are more abundant and predictable than foods appropriate for nestlings, or (b) when birds' perception of predation risk, which can be influenced by human disturbance, is greater than the real risk. By provisioning or attending their nests more or less than what is appropriate given the environmental level of resources and risks, the behavior of suburban parents may be contributing to high levels of nest failure during the nesting stage. To determine whether maladaptive parental care influences nest survival during the nestling stage, I conducted an experiment using Florida Scrub-Jays (Aphelocoma coerluscens). Suburban scrub-jays have lower nest survival during the nestling stage but higher survival during the incubation stage relative to wildland jays. Both predators and food abundance vary greatly between suburban and wildland scrub. The suburbs have a greater abundance of predators that may prey on both adult scrub-jays and their nests and more foods appropriate for adults but less nestling-appropriate food. This variation in risks and resources should affect the parental care behavior of suburban scrub-jays, which in turn may affect patterns of nest survival. In pre-treatment observations, I found that suburban females spent more time brooding than wildland birds but suburban males did not provision any more than wildland males. Experimentally increasing the perception of adult predation risk reduced parental care in both suburban and wildland females. Increasing the availability of nestling food reduced parental care in suburban females but had no effect in wildland females. Increasing food availability, but not predation risk, decreased call rates but increased call frequency in nestling scrub-jays from both habitats. However, neither parental care nor food availability had much influence on nest survival during the nestling stage. Instead, side nest concealment and the presence of helpers were the most important variables in nest survival analyses prompting other explanations besides maladaptive parental behavior or lack of nestling food resources for the habitat-specific difference in nest survival during the nestling stage.

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