This collection includes most of the ASU Theses and Dissertations from 2011 to present. ASU Theses and Dissertations are available in downloadable PDF format; however, a small percentage of items are under embargo. Information about the dissertations/theses includes degree information, committee members, an abstract, supporting data or media.

In addition to the electronic theses found in the ASU Digital Repository, ASU Theses and Dissertations can be found in the ASU Library Catalog.

Dissertations and Theses granted by Arizona State University are archived and made available through a joint effort of the ASU Graduate College and the ASU Libraries. For more information or questions about this collection contact or visit the Digital Repository ETD Library Guide or contact the ASU Graduate College at gradformat@asu.edu.

Displaying 1 - 4 of 4
Filtering by

Clear all filters

151016-Thumbnail Image.png
Description
Human recreation on rangelands may negatively impact wildlife populations. Among those activities, off-road vehicle (ORV) recreation carries the potential for broad ecological consequences. A study was undertaken to assess the impacts of ORV on rodents in Arizona Uplands Sonoran Desert. Between the months of February and September 2010, rodents were

Human recreation on rangelands may negatively impact wildlife populations. Among those activities, off-road vehicle (ORV) recreation carries the potential for broad ecological consequences. A study was undertaken to assess the impacts of ORV on rodents in Arizona Uplands Sonoran Desert. Between the months of February and September 2010, rodents were trapped at 6 ORV and 6 non-ORV sites in Tonto National Forest, AZ. I hypothesized that rodent abundance and species richness are negatively affected by ORV use. Rodent abundances were estimated using capture-mark-recapture methodology. Species richness was not correlated with ORV use. Although abundance of Peromyscus eremicus and Neotoma albigula declined as ORV use increased, abundance of Dipodomys merriami increased. Abundance of Chaetodipus baileyi was not correlated with ORV use. Other factors measured were percent ground cover, percent shrub cover, and species-specific shrub cover percentages. Total shrub cover, Opuntia spp., and Parkinsonia microphylla each decreased as ORV use increased. Results suggest that ORV use negatively affects rodent habitats in Arizona Uplands Sonoran Desert, leading to declining abundance in some species. Management strategies should mitigate ORV related habitat destruction to protect vulnerable populations.
ContributorsReid, John Simon (Author) / Brady, Ward (Thesis advisor) / Miller, William (Committee member) / Bateman, Heather (Committee member) / Arizona State University (Publisher)
Created2012
157012-Thumbnail Image.png
Description
Human-inhabited or -disturbed areas pose many unique challenges for wildlife, including increased human exposure, novel challenges, such as finding food or nesting sites in novel structures, anthropogenic noises, and novel predators. Animals inhabiting these environments must adapt to such changes by learning to exploit new resources and avoid danger. To

Human-inhabited or -disturbed areas pose many unique challenges for wildlife, including increased human exposure, novel challenges, such as finding food or nesting sites in novel structures, anthropogenic noises, and novel predators. Animals inhabiting these environments must adapt to such changes by learning to exploit new resources and avoid danger. To my knowledge no study has comprehensively assessed behavioral reactions of urban and rural populations to numerous novel environmental stimuli. I tested behavioral responses of urban, suburban, and rural house finches (Haemorhous mexicanus) to novel stimuli (e.g. objects, noises, food), to presentation of a native predator model (Accipiter striatus) and a human, and to two problem-solving challenges (escaping confinement and food-finding). Although I found few population-level differences in behavioral responses to novel objects, environment, and food, I found compelling differences in how finches from different sites responded to novel noise. When played a novel sound (whale call or ship horn), urban and suburban house finches approached their food source more quickly and spent more time on it than rural birds, and urban and suburban birds were more active during the whale-noise presentation. In addition, while there were no differences in response to the native predator, rural birds showed higher levels of stress behaviors when presented with a human. When I replicated this study in juveniles, I found that exposure to humans during development more accurately predicted behavioral differences than capture site. Finally, I found that urban birds were better at solving an escape problem, whereas rural birds were better at solving a food-finding challenge. These results indicate that not all anthropogenic changes affect animal populations equally and that determining the aversive natural-history conditions and challenges of taxa may help urban ecologists better understand the direction and degree to which animals respond to human-induced rapid environmental alterations.
ContributorsWeaver, Melinda (Author) / McGraw, Kevin J. (Thesis advisor) / Rutowski, Ronald (Committee member) / Pratt, Stephen (Committee member) / Bateman, Heather (Committee member) / Deviche, Pierre (Committee member) / Arizona State University (Publisher)
Created2018
171640-Thumbnail Image.png
Description
When most people think of Phoenix, Arizona, they think of sprawling cityscapesand hot desert mountains full of saguaros and other cacti. They rarely think of water and fish, and yet, the Arizona landscape is home to many lakes, ponds, rivers and streams, full of both native fish and sportfish, including in the

When most people think of Phoenix, Arizona, they think of sprawling cityscapesand hot desert mountains full of saguaros and other cacti. They rarely think of water and fish, and yet, the Arizona landscape is home to many lakes, ponds, rivers and streams, full of both native fish and sportfish, including in the urban areas. According to the report by DeSemple in 2006, between the years 2001 and 2006, the Rio Salado Environmental Restoration Project worked to revitalize the dry river bed that runs through Phoenix, that included the construction of two urban ponds, the Demonstration Pond and the Reservoir Pond. At the start of this study, it was unknown what vertebrate species inhabited these ponds, but it was known that these urban ponds have been used to dump unwanted aquatic pets. The bluegill Lepomis macrochirus was found to reside in both ponds, and as it is such an important sportfish species, it was chosen as the focal species for these studies, which took place over periods in March, May, July, and September of 2021. Single-season occupancy models were used to attempt to determine how L. macrochirus, use the microhabitats within the system, and a multi-season model was used to estimate their recruitment, and seasonal changes in occupancy. In addition, this study also attempts to understand the size structures of the L. macrochirus population in the Reservoir Pond and the population in the Demonstration Pond, and if that size structure varies from March to September. As the populations of these ponds are physically isolated from one another, statistical tests were also done to determine if the size structures of the two populations of L. macrochirus differ from one another and found that the two populations do indeed differ from one another, but only during two of the sampling periods.
ContributorsKeister, Emily Jan (Author) / Saul, Steven (Thesis advisor) / Bateman, Heather (Committee member) / Suzart de Albuquerque, Fabio (Committee member) / Arizona State University (Publisher)
Created2022
161793-Thumbnail Image.png
Description
Spatial and temporal patterns of biodiversity are shaped, in part, by the resources available to biota, the efficiency of resource transfer through the food web, and variation in environmental conditions. Stream and riparian zones are dynamic systems connected through reciprocal resource exchange and shaped by floods, droughts, and long-term patterns

Spatial and temporal patterns of biodiversity are shaped, in part, by the resources available to biota, the efficiency of resource transfer through the food web, and variation in environmental conditions. Stream and riparian zones are dynamic systems connected through reciprocal resource exchange and shaped by floods, droughts, and long-term patterns in the quantity, timing, and variability of streamflow (flow regime). The interdependent nature of the stream-riparian ecosystem defies the scope of any single discipline, requiring novel approaches to untangle the controls on ecological processes. In this dissertation, I explored multiple mechanisms through which streamflow and energy flow pathways maintain the community and trophic dynamics of desert stream and riparian food webs. I conducted seasonal sampling of Arizona streams on a gradient of flow regime variability to capture fluctuations in aquatic communities and ecosystem production. I found that flow regime shapes fish community structure and the trajectory of community response following short-term flow events by constraining the life history traits of communities, which fluctuate in prevalence following discrete events. Streamflow may additionally constrain the efficiency of energy flow from primary producers to consumers. I estimated annual food web efficiency and found that efficiency decreased with higher temperature and more variable flow regime. Surprisingly, fish production was not related to the rate of aquatic primary production. To understand the origin of resources supporting aquatic and riparian food webs, I studied the contribution of aquatic and terrestrial primary production to consumers in both habitats. I demonstrated that emergent insects “recycled” terrestrial primary production back to the riparian zone, reducing the proportion of aquatic primary production in emergent insect biomass and riparian predator diet. To expand the concept of stream and riparian zones as an integrated ecosystem connected by resource cycling through the food web, I introduced a quantitative framework describing reciprocal interconnections across spatial boundaries and demonstrated strong aquatic-riparian interdependencies along an Arizona river. In this dissertation, I develop a novel perspective on the stream-riparian ecosystem as an intertwined food web, which may be vulnerable to unforeseen impacts of global change if not considered in the context of streamflow and resource dynamics.
ContributorsBaruch, Ethan Max (Author) / Sabo, John (Thesis advisor) / Bateman, Heather (Committee member) / Cease, Arianne (Committee member) / Grimm, Nancy (Committee member) / Arizona State University (Publisher)
Created2021