Matching Items (4)
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- Creators: Bateman, Heather
- All Subjects: Wildlife conservation
Description
The Southwestern Willow Flycatcher (Empidonax traillii extimus) has been studied for over two decades and listed as endangered for most of that time. Though the flycatcher has been granted protected status since 1995, critical habitat designation for the flycatcher has not shared the same history. Critical habitat designation is essential for achieving the long-term goals defined in the flycatcher recovery plan where emphasis is on both the protection of this species and "the habitats supporting these flycatchers [that] must be protected from threats and loss" (U.S. Fish and Wildlife Service 2002). I used a long-term data set of habitat characteristics collected at three study areas along the Lower Colorado River to develop a method for quantifying habitat quality for flycatcher. The data set contained flycatcher nest observations (use) and habitat availability (random location) from 2003-2010 that I statistically analyzed for flycatcher selection preferences. Using both Pearson's Chi-square test and SPSS Principal Component Analysis (PCA) I determined that flycatchers were selecting 30 habitat traits significantly different among an initial list of 127 habitat characteristics. Using PCA, I calculated a weighted value of influence for each significant trait per study area and used those values to develop a habitat classification system to build predictive models for flycatcher habitat quality. I used ArcGIS® Model Builder to develop three habitat suitability models for each of the habitat types occurring in western riparian systems, native, mixed exotic and exotic dominated that are frequented by breeding flycatchers. I designed a fourth model, Topock Marsh, to test model accuracy on habitat quality for flycatchers using reserved accuracy assessment points of previous nest locations. The results of the fourth model accurately predicted a decline in habitat at Topock Marsh that was confirmed by SWCA survey reports released in 2011 and 2012 documenting a significant decline in flycatcher productivity in the Topock Marsh study area.
ContributorsChenevert-Steffler, Ann (Author) / Miller, William (Thesis advisor) / Bateman, Heather (Committee member) / Alford, Eddie (Committee member) / Arizona State University (Publisher)
Created2013
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 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
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
As white-nose syndrome (WNS) spreads across North America, generating baseline data on bats hibernating outside of the affected area is critical. To illustrate, despite the imminent arrival of Pseudogymnoascus destructans (Pd) to Arizona (AZ), little is known about bat hibernation in the Southwest. With the current amount of information, if Pd spreads throughout the state, detection of cases would be limited, and severity of disease and magnitude of mortality impossible to accurately estimate. Thus, my study monitored hibernating bats in AZ to increase knowledge and investigate potential WNS impacts on these populations. Utilizing passive acoustic monitoring, internal cave surveys, environmental monitoring, and thermal imaging, my study quantified microclimate preferences, hibernation lengths, hibernation behaviors, population dynamics, and species compositions of bats hibernating in three north-central AZ caves. Hibernation lasted between 104 and 162 days, from late October through mid- March, during which time bats (primarily Corynorhinus townsendii and Myotis species) roosted at locations with an average of 4.7oC (range = -0.2oC – 12.1oC), 59.6% relative humidity (range = 39.6% - 75.9%), and 0.4 kPa water vapor pressure deficit (range = 0.2 kPa – 0.8 kPa). A maximum of 40 individuals were observed in any hibernacula and clustering behavior occurred in only 4.1% of torpid bats. Bats selected cold and dry roost sites within caves. Results suggest Pd could proliferate on some bats hibernating in colder areas of AZ hibernacula, yet the range of observed roost humidities was lower than optimal for Pd growth. Hibernation length in north-central AZ is longer than predicted for Myotis species at similar latitudes and may be long enough to pose over- winter survival risks if WNS emerges in AZ populations. Yet, a natural tendency for mid-winter activity, which I observed by multiple species, may allow for foraging opportunities and water replenishment, and therefore promote survival in bats utilizing these arid and cold habitats in winter. Additionally, the relatively solitary behaviors I observed, including virtually no clustering activity and a maximum of 40 bats per hibernacula, may keep rates of Pd transmission low in these Southwest bat populations.
ContributorsHutcherson, Hayden K (Author) / Bateman, Heather (Thesis advisor) / Moore, Marianne (Committee member) / Lewis, Jesse (Committee member) / Arizona State University (Publisher)
Created2023