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Breakout session from the Living the Future 7 Conference, April 30-May 3, 2008, University of Arizona Libraries, Tucson, AZ. / The University of Arizona Libraries has developed several collaborative projects at local, regional and national levels. For example, the UA Libraries and the Office of Arid Land Studies at the University of Arizona have worked together on Rangelands West, a collaborative effort involving 19 Western land-grant universities. The UA Libraries and the Office of Arid Land Studies have recently partnered on a new initiative, the Sonoran Desert Knowledge Exchange (SDKE). SDKE is an emerging collaborative effort led by the UA Libraries involving more than 25 educational institutions, community organizations, and research centers. The presenters will share information about the vision of SDKE, the development and content of the project, discuss the roles of SDKE partners and participants, and examine the evolution of SDKE through the lens of collaboration. Issues surrounding the complexities of collaboration will be explored: How are transitions handled from library-led projects to more collaborative projects? What long-term vision is required to incorporate collaborative elements into project stages? What are the challenges and rewards of collaborative projects?

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The vegetation associations in the Eastern San Cristobal Valley of Barry M. Goldwater Range-East (BMGR) were mapped using a combination of field surveys (relevés) and interpretation of aerial imagery in order to contribute to ongoing mapping efforts of Barry M. Goldwater Range-East. Throughout the San Cristobal Valley, 149 relevé samples were collected to characterize the vegetation associations. Seventeen vegetation associations were identified and mapped, including a new Larrea tridentata/Ambrosia dumosa/Grusonia kunzei (Creosote bush-White bursage-Devil's cholla) association. Accuracy assessment of the map was conducted using a contingency table finding the map to be 82% accurate. Route proliferation in the San Cristobal Valley of Barry M. Goldwater Range-East (BMGR) was also mapped and measured using remotely sensed imagery in geographic information systems and modeled with geographical variables in a multivariate regression. Throughout the San Cristobal Valley study site, 6,878 km of unauthorized routes were identified. Geographic explanatory variables distance from slopes greater than 34% (b = -3.252e-5, p<0.001) and the most influential variable distance from unauthorized routes (b = -0.006568, p<0.001) were tested for significance and influence in predicting unauthorized route density. The resulting model, built from the two significant geographic variables in a multivariate regression, was able to explain 57% of the variability in the data. The results from this study have shown that through the use of GIS and remote sensing, unauthorized route density can be predicted by geographic variables which can then be used to make future route management decisions.

Upper Respiratory Tract Disease (URTD), caused by the pathogens Mycoplasma agassizii and M. testudineum, has been documented in the desert tortoise (Gopherus agassizii). Although URTD was identified as a putative agent that led to federal listing of the Mojave population of the desert tortoise, little is known about this disease in the Sonoran population of the desert tortoise. The purpose of this study was to determine: 1) the prevalence of URTD across an urban gradient in Greater Tucson, Arizona, 2) the relationship between URTD and captive and free-ranging tortoises in Mohave, Maricopa, and Pima counties in Arizona, and 3) the effects of URTD on desert tortoise home range size and winter temperature selection.

About 1,600,000 ha of desert mule deer range in Mexico are currently altered with vegetation clear-cutting and establishment of buffelgrass pastures. Consequently, the availability of resources as cover and forage from scrub vegetation has been reduced for mule deer. No previous research has been conducted to investigate how desert mule deer respond to those alterations. Therefore, the purpose of this research was to examine movements of mule deer, evaluate their home range sizes and determine habitat use, and analyze their diets in areas of central and western Sonora, Mexico. The approach involved the use of radiotelemetry techniques and GIS programs to calculate home range sizes, examine selection of vegetation associations, and identify the specific components of habitat that distinguished the characteristics of selected sites by desert mule deer. I used the microhistological technique to determine botanical components of desert mule deer diets, and compare diets of desert mule deer and cattle in habitat with buffelgrass pastures. Diet analyses included spatial and temporal comparisons of diversity and similarity indices. Sizes of home ranges were larger in the more arid environments of western Sonora (27.3 km2) than in central Sonora (14.5 km2). Desert mule deer used altered habitat differently than use areas without buffelgrass, however, there was no difference in the size of home ranges of mule deer from inside buffelgrass areas and the size of home ranges of deer in native scrub vegetation. Thermal cover, ground cover, and percent of gravel in the ground were the variables that distinguished locations selected by desert mule deer. Desert mule deer selected xeroriparian vegetation and sites closer to water sources. Water sources may have influenced mule deer to stay in buffelgrass areas despite the lack of cover and forage from shrubs and trees. For diets of mule deer, I identified 96 plant species, 69 of which have not previously been reported as forage for this herbivore. Desert mule deer and cattle shared 45 forage species from central Sonora. However, biological overlap of diets occurred only for spring. Results from these studies provide information to understand ecological relationships of desert mule deer on altered habitats.

abstract: 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. / Dissertation/Thesis / M.S. Applied Biological Sciences 2012

abstract: The introduction of livestock to the vast majority of public lands may be used to simulate the conditions provided by herbivorous grazers in the past, however little data has been collected on the effects of livestock grazing in Sonoran desert habitats. Vegetative species that are characteristic of the Arizona Upland subdivision of the Sonoran desert did not evolve with extensive grazing by large ungulate populations, and therefore the response to livestock grazing is of particular interest. Four historic Parker 3-step clusters in south-central Arizona were sampled in three cohorts between 1953 and 2016 to interpret changes in rangeland health using soil coverage data, species richness and frequency, and long-term photo point comparisons. Cattle grazing was active across the allotment until 1984, allowing approximately 30 years of rest before the third and final cohort was measured. Over the entirety of this study, there was a 66.67% increase in perennial basal hits, a 56.29% increase in rock, and a 44.55% increase of forage basal hits. Decreases were seen in litter (-57.69%) and bare soil hits (-8.76%). Cluster 3 consistently had a lower percent of cover across all classes of vegetation in the 2014 cohort (-81.61%), however the average percent of cover increased by 63.16% (40 hits) across the allotment. Available species richness data from 1971 and 2014 cohorts indicates a 112% increase in unique species; however, species richness increases in the 2014 cohort are largely based on recruitment of non-palatable species (71%). Although the status of some species were undetermined, all individuals identified to species in the invader class (non-palatable) were determined to be native to the study site. Perennial grass frequency became less abundant over the duration of this study, while growth was predominantly observed in shrubs. Increases in species frequency was detected on two of the four clusters measured in the 2014 cohort; the growth was primarily observed in jojoba (Simmondsia chinensis), oak (Quercus spp.), and catclaw acacia (Senegalia greggii) in C4, and hopseed bush (Dodonaea viscosa) in C2. / Dissertation/Thesis / Masters Thesis Applied Biological Sciences 2018

abstract: Biological diversity is threatened by increasing anthropogenic modification of natural environments and increasing demands on natural resources. Sonoran desert tortoises (Gopherus morafkai) currently have Candidate status under the Endangered Species Act (ESA) based on health and habitat threats. To ensure this animal persists in the midst of multiple threats requires an understanding of the life history and ecology of each population. I looked at one physiological and one behavioral aspect of a population of tortoises at the Sugarloaf Mountain (SL) study site in central Arizona, USA. I used 21 years of capture-recapture records to estimate growth parameters of the entire population. I investigated habitat selection of juvenile tortoises by selecting 117 locations of 11 tortoises that had been tracked by radio-telemetry one to three times weekly for two years, selecting locations from both summer active season and during winter hibernation. I compared 22 microhabitat variables of tortoise locations to random SL locations to determine habitat use and availability. Male tortoises at SL reach a greater asymptotic length than females, and males and females appear to grow at the same rate. Juvenile tortoises at the SL site use steep rocky hillsides with high proportions of sand and annual vegetation, few succulents, and enclosed shelters in summer. They use enclosed shelters on steep slopes for winter hibernation. An understanding of these features can allow managers to quantify Sonoran desert tortoise habitat needs and life history characteristics and to understand the impact of land use policies. / Dissertation/Thesis / M.S. Applied Biological Sciences 2012

abstract: Modified and artificial water sources can be used as a management tool for game and non-game wildlife species. State, federal, and private agencies allocate significant resources to install and maintain artificial water sources (AWS) annually. Capture mark recapture methods were used to sample small mammal communities in the vicinity of five AWS and five paired control sites (treatments) in the surrounding Sonoran desert from October 2011 to May 2012. I measured plant species richness, density, and percent cover in the spring of 2012. A Multi-response Permutation Procedure was used to identify differences in small mammal community abundance, biomass, and species richness by season and treatment. I used Principle Component Analysis to reduce 11 habitat characteristics to five habitat factors. I related rodent occurrence to habitat characteristics using multiple and logistic regression. A total of 370 individual mammals representing three genera and eight species of rodents were captured across 4800 trap nights. Desert pocket mouse (Chaetodipus penicillatus) was the most common species in both seasons and treatments. Whereas rodent community abundance, biomass, and richness were similar between seasons, community variables of AWS were greater than CS. Rodent diversity was similar between treatments. Desert pocket mouse abundance and biomass were twice as high at AWS when compared to controls. Biomass of white-throated woodrat (Neotoma albigula) was five times greater at AWS. Habitat characteristics were similar between treatments. Neither presence of water nor distance to water explained substantial habitat variation. Occurrence of rodent species was associated with habitat characteristics. Desert rodent communities are adapted for arid environments (i.e. Heteromyids) and are not dependent on "free water". Higher abundances of desert pocket mouse at AWS were most likely related to increased disturbance and debris and not the presence of water. The results of this study and previous studies suggest that more investigation is needed and that short term studies may not be able to detect interactions (if any) between AWS and desert small mammal communities. / Dissertation/Thesis / M.S. Applied Biological Sciences 2013