Matching Items (5)
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- All Subjects: Urbanization
- All Subjects: Urban animals--Variation.
- Creators: Allen, Daniel
- Creators: Lewis, Jesse S
Description
Urbanization is a landscape-level alteration of habitat that can lead to habitat fragmentation, degradation, and the introduction of nonnative species. Due to their life history characteristics, mammalian predators are particularly vulnerable to these effects. The categorization of many species as synanthropic, benefiting from human development, has been difficult as species have a gradient of responses to urbanization. Although coyotes, gray foxes and bobcats have all been shown to benefit from light to moderate levels of urbanization, often due to the increase in food resources, they typically require access to natural areas as escape cover. Camera traps at varying distances were used to document mesopredator response to the urban edge of Gold Canyon, Arizona from November 2015 through March 2016. Coyote, gray fox and bobcat relative abundance did not vary with distance to urban edge during this time period. Although, negative trends suggest that a larger scale study may reveal a negative relationship between distance to urban edge and mesopredator abundance for all 3 of these species. The efficacy of different baits at increasing mesopredator detections was also tested, with insignificant results. However, coyotes seemed to be more likely to interact with Carman's Raccoon Lure No. 2 than coyote urine. Understanding the responses of mesopredators to urbanization will allow us to better coexist with these vulnerable species as land continues to be developed at high rates across the globe.
ContributorsEvans, Jacquelyn Diane (Author) / Cunningham, Stanley (Thesis director) / Allen, Daniel (Committee member) / College of Letters and Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Urban riparian corridors have the capacity to maintain high levels of abundance and biodiversity. Additionally, urban rivers also offer environmental amenities and can be catalysts for social and economic revitalization in human communities. Despite its importance for both humans and wildlife, blue space in cities used by waterbirds has received relatively little focus in urban bird studies. My principal objective was to determine how urbanization and water availability affect waterbird biodiversity in an arid city. I surveyed 36 transects stratified across a gradient of urbanization and water availability along the Salt River, a LTER long-term study system located in Phoenix, Arizona. Water physiognomy (shape and size) was the largest factor in shaping the bird community. Connectivity was an important element for waterbird diversity, but not abundance. Urbanization had guild-specific effects on abundance but was not important for waterbird diversity. Habitat-level environmental characteristics were more important than land use on waterbird abundance, as well as diversity. Diving and fish-eating birds were positively associated with large open bodies of water, whereas dabbling ducks, wading birds, and marsh species favored areas with large amounts of shoreline and emergent vegetation. My study supports that Phoenix blue space offers an important subsidy to migrating waterbird communities; while alternative habitat is not a replacement, it is important to consider as part of the larger conservation picture as traditional wetlands decline. Additionally, arid cities have the potential to support high levels of waterbird biodiversity, heterogeneous land use matrix can be advantageous in supporting regional diversity, and waterbirds are tolerant of urbanization if proper resources are provided via the habitat. The implications of this study are particularly relevant to urban planning in arid cities; Phoenix alone contains over 1,400 bodies of water, offering the opportunity to design and improve urban blue space to optimize potential habitat while providing public amenities.
ContributorsBurnette, Riley (Author) / Bateman, Heather (Thesis advisor) / Franklin, Janet (Committee member) / Allen, Daniel (Committee member) / Arizona State University (Publisher)
Created2016
Description
Urban Heat Island (UHI) is considered as one of the major problems in the 21st century posed to human beings as a result of urbanization and industrialization of human civilization. The large amount of heat generated from urban structures, as they consume and re-radiate solar radiations, and from the anthropogenic heat sources are the main causes of UHI. The two heat sources increase the temperatures of an urban area as compared to its surroundings, which is known as Urban Heat Island Intensity (UHII). The problem is even worse in cities or metropolises with large population and extensive economic activities. The estimated three billion people living in the urban areas in the world are directly exposed to the problem, which will be increased significantly in the near future. Due to the severity of the problem, vast research effort has been dedicated and a wide range of literature is available for the subject. The literature available in this area includes the latest research approaches, concepts, methodologies, latest investigation tools and mitigation measures. This study was carried out to review and summarize this research area through an investigation of the most important feature of UHI. It was concluded that the heat re-radiated by the urban structures plays the most important role which should be investigated in details to study urban heating especially the UHI. It was also concluded that the future research should be focused on design and planning parameters for reducing the effects of urban heat island and ultimately living in a better environment.
ContributorsRizwan, Ahmed Memon (Author) / Dennis, Leung Y.C. (Author) / Liu, Chunho (Author)
Created2007-09-27
Description
Urbanization is a primary driver of ecological change and occurs across a gradient from low- to high- density development. Wildlife species can exhibit different responses to urbanization, with some species being more sensitive than others. Further, wildlife communities can exhibit varying patterns of species richness across the gradient of urbanization, where species richness can either decrease linearly or peak at intermediate levels of urbanization, consistent with the intermediate disturbance hypothesis (IDH). For chapter one, the objective was to evaluate the response of bats to urbanization across seasons. It was predicted that bat species would exhibit different responses to urbanization and that bats would increase use of urbanized areas in the summer season, where food and water resources were assumed to be greater. For chapter two, the objective was to evaluate species richness of bats across the gradient of urbanization in the summer season. Species richness of bats was predicted to either decrease linearly or peak at moderate levels of urban intensity. To test these hypotheses, 50 sites across the gradient of urbanization were sampled during four seasons using stationary acoustic bat monitors. Fourteen bat species were identified during 1000 nightly occasions. Consistent with chapter one predictions, bat species exhibited different responses to urbanization, with most bats being sensitive to urbanization. Counter to predictions, most bats did not appear to shift their response to urbanization across seasons. However, two bats (i.e., big brown bat and Yuma myotis) exhibited higher use of urbanized areas in the summer compared to other seasons. Consistent with chapter two predictions, species richness of bats decreased with increasing urban intensity. Results from this study demonstrate that most bats in the community were sensitive to urbanization, which is potentially related to species traits and has important conservation implications. First, it is likely important to maintain high-quality undeveloped habitat with low anthropogenic disturbance in wildland areas for species that are sensitive to urbanization and to maximize species richness. In addition, for bats that are tolerant of urbanization and to increase species richness in urbanized areas, it is likely important to preserve resources in urbanized areas and increase landscape connectivity.
ContributorsDwyer, Jessie (Author) / Lewis, Jesse S (Thesis advisor) / Moore, Marianne S (Committee member) / Saul, Steven E (Committee member) / Arizona State University (Publisher)
Created2021
Description
With a growing majority of humans living within cities and towns, urbanization is one of the most persistent drivers of change in global land use and challenges to sustainability and biodiversity conservation. The development of cities and towns can substantially shape local and regional environments in which wildlife communities persist. Although urbanization can negatively affect wildlife communities – through processes such as habitat fragmentation and non-native species introduction – cities can also provide resources to wildlife, such as through food, water, and space, creating potential opportunities for conservation. However, managing wildlife communities persisting in urbanizing landscapes requires better understanding of how urbanized landscapes influence the ability of wildlife to coexist with one another and with people at local and regional scales. In this dissertation, I addressed these research needs by evaluating the environmental and human factors driving dynamic wildlife community distributions and people’s attitudes towards wildlife. In my first two chapters,I used wildlife camera data collected from across the Phoenix Metropolitan Area, AZ to examine seasonal patterns of wildlife space use, species richness, and interspecific interactions across levels of urbanization with varying landscape characteristics, including plant productivity and spatial land use heterogeneity. Here I found that urbanization was a primary driver of wildlife community characteristics within the region, but that seasonal resource availability and landscape heterogeneity could have mediating influences that require further exploration. In my third chapter, I partnered
with wildlife researchers across North America to examine how relationships between urbanization and community composition vary among cities with distinct social-ecological characteristics, finding that effects of local urbanization were more negative in warmer, less vegetated, and more urbanized cities. In my fourth and final chapter, I explored the potential for human-wildlife coexistence by examining how various ideological, environmental, and sociodemographic factors influenced Phoenix area residents’ level of comfort living near different wildlife groups. Although I found that residents’ attitudes were primarily shaped by their relatively static wildlife values, comfort living near wildlife also depended on the characteristics of the neighboring environment, of the residents, and of the wildlife involved, indicating the potential for facilitating conditions for human-wildlife coexistence. Altogether, the findings of this dissertation suggest that the management of wildlife and their interactions with people within cities would benefit from more proactive and holistic consideration of the interacting environmental, wildlife, and human characteristics that influence the persistence of biodiversity within an increasingly urbanized world.
ContributorsHaight, Jeffrey Douglas (Author) / Hall, Sharon J (Thesis advisor) / Lewis, Jesse S (Thesis advisor) / Larson, Kelli L (Committee member) / Wu, Jianguo (Committee member) / Arizona State University (Publisher)
Created2023