Browsing by Author "Boone, Randall, advisor"

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Open Access
Analysis and modeling of what honey bees (Apis mellifera L.) bring back to the hive and how that affects the health of the hive and humans
(Colorado State University. Libraries, 2023) Awad, Mai Mousa, author; Boone, Randall, advisor; Kato, Takamitsu, advisor; Borch, Thomas, committee member; Ode, Paul, committee member
Apis mellifera L. populations are decreasing at an alarming rate. Over the past 20 years, the number of managed honey bee colonies has declined, and this decline has become a global concern. This study focuses on chemical stressors that are found to affect the bee population. We used direct sampling to examine the variation of pesticides and heavy metals concentrations in two different landscape contexts. Subsequently, we extrapolated the risk of these toxins' residues on Apis sp. based on current literature. We found no spatial variation in metal concentrations in pollen and honey samples collected from urban and agricultural areas. Likewise, we observed no spatial variation in pesticide concentrations in pollen and honey samples collected from urban versus agricultural areas. In addition to chemical factors, we studied the nutritional factor by investigating the effect of spatial variability on the amount of stored pollen and the floral diversity of in-hive pollen. Furthermore, we estimated the most abundant botanical families that will identify honey bees' protein-source preferences. The results indicated a spatial variation in Shannon-Weaver diversity, demonstrating a higher diversity index with a wider variety of pollen taxa collected from urban sites compared to the agricultural ones with a lower diversity index with less pollen taxonomic variety. The alarming decrease in honey bees' population urges researchers to investigate the factors that enhance the deterioration of bees' population. A few models explained these factors individually. We designed a NetLogo model to assess multiple factors that would intensify the impact of the Colony Collapse Disorder phenomenon, by investigating the spatial variation of bees' exposure to a distinctive environmental toxin and the quantities of these toxins in hive products. The model indicated that there were significant spatial variation effects on the pesticides and heavy metal concentrations in the accumulated pollen and nectar inside the beehive. Pesticides and heavy metal accumulation in bees' products are mainly caused by human activities, which can affect human health by their consuming contaminated honey. Based on the results of honey analysis for pesticides and heavy metals we performed in the first study, we decided to select one pesticide and a pesticide synergist along with the most two abundant heavy metals to investigate the synergistic effect of cytotoxicity and genotoxicity that would result from the interaction of one major pesticide in honey: Imidacloprid and a pesticide synergist: Piperonyl butoxide, and two major heavy metals in honey: Lead and Selenium, at the cellular level in mammalian cells, where we found different interactional effects of these compounds on cell survival, cell apoptosis, oxidative stress, and sister chromatid induction.
Embargo
Big data analysis and coupled human-natural systems modeling to examine the influence of socioeconomic and environmental factors on protected areas
(Colorado State University. Libraries, 2025) Zarria-Samanamud, Melody Rocio, author; Boone, Randall, advisor; Bowser, Gillian, advisor; Havrilla, Caroline, committee member; Jones, Kelly, committee member; Klein, Julia, committee member; Young, Kenneth, committee member
This dissertation aims to deepen our understanding of how human and environmental factors affect protected areas through a social-ecological systems approach. This dissertation comprises two topics. The first consists of determining the level of landscape changes in protected areas and identifying the anthropogenic and environmental factors associated with these changes. The other topic explores the potential impacts of climate change and land management on ecosystems, agropastoral families' livelihoods, and livestock grazing behavior in the Peruvian Andes. I used a social-ecological systems analytical approach to have an interdisciplinary perspective on how the biophysical and socioeconomic contexts of protected areas impact their conservation effectiveness and influence the pressures they face. My analyses used innovative analytical approaches, including big data analysis and agent-based modeling, to offer new insights into these critical issues. In Chapter 2, I quantified changes in the landscape of protected areas worldwide and identified the critical anthropogenic and biophysical factors associated with these changes. I estimated landscape metrics for about 11,000 protected areas for 2000 and 2020 using open-source spatial data and performed random forest analyses. Changes in the landscape of protected areas and their associated socioeconomic and environmental factors differed by region and cover classes. In general, landscape changes were mainly influenced by anthropogenic factors, such as the level of human development, agricultural expansion, population density, and the protected area's regulation level. The main biophysical factors critical in explaining landscape changes were slope and precipitation. In Chapter 3, I examined the ecological impacts of climate change in a mountain landscape in the Andes of Peru. I parametrized an ecosystem-process model (L-Range) to Andean environmental conditions to capture ecosystem responses to climate change. Climate change impacts on Andean ecosystems vary by cover class, topographic position, and climate scenario. Shrublands and woodlands will become more productive, whereas wetlands are projected to experience a decline in primary production. However, under the most extreme climate scenario, all cover classes will undergo a reduction in primary production. In Chapter 4, I explored the potential economic and ecological impacts of various land management scenarios in a valley of Huascaran National Park in the Andes of Peru used as grazing lands by a local community. I built the Agent-based model of laNd management Dynamics and Ecosystem Services (ANDES) that represents livestock grazing behavior, grazing management, and household economies. I coupled the ANDES/L-Range models to deepen my understanding of how new management scenarios and future climate conditions would impact ecosystems and families' economies. Families' incomes were reduced under the scenarios involving a reduction in livestock population. The biomass availability was markedly higher only under the scenarios that involved livestock population reduction and the implementation of new rotational grazing schemes. These findings reveal that not only livestock numbers should be adjusted but also livestock distribution. In Chapter 5, I analyzed how different grazing management schemes impact livestock forage consumption, grazing behavior, and body condition of cattle and sheep. I analyzed information derived from the Livestock Grazing Behavior sub-model of ANDES. Livestock responses to grazing management varied by species. Forage consumption and body condition were the highest under the scenarios that implied livestock population reduction. Moreover, livestock mortality was the lowest under these scenarios. In general, the below-optimal performance of livestock across all management scenarios suggests adjusting stocking rate and grazing frequency. The key insights derived from Chapters 3, 4, and 5 are as follows. The Andean ecosystems' response to climate change will exhibit considerable variability. While a reduction in primary production is anticipated across most cover classes, except for woodlands, the impacts of climate change will also be influenced by the ecosystem's landscape setting. Livestock management practices, particularly those that involve reducing livestock numbers, will result in better animal body condition. The implementation of regulatory policies, such as reducing livestock populations and limiting park land access, will have significant economic repercussions on families, especially middle-aged and elderly individuals, whose income primarily relies on livestock production. My study provides critical information for the sustainable management and conservation of protected areas and can serve as the basis for designing integrative policies that balance conservation and sustainable development. The development of conservation and sustainability policies must address the factors impacting protected areas and their surroundings. To achieve this, these policies should incorporate diverse perspectives and foster engagement with local communities.
Open Access
Evalutating the effects of wildfire in piñon-juniper woodlands on bighorn sheep habitat and vegetation composition
(Colorado State University. Libraries, 2014) Wilson, Benjamin R., author; Boone, Randall, advisor; Evangelista, Paul, committee member; Wittemyer, George, committee member
I evaluated the efficacy of using woodland fire to alter vegetation composition in a manner that augments desert bighorn sheep (Ovis canadensis nelsoni) habitat in the Black Ridge Canyons Wilderness Area in western Colorado. I applied generalized linear mixed models to estimate pre-fire ewe habitat selection and then simulated a hypothetical widespread fire to spatially predict where fire would be most beneficial in expanding habitat. I found that ewes were avoiding habitats with high woodland canopy cover, the habitat most likely to be removed by fire. Given the removal of all woodlands, it is likely that habitat expansion would occur in areas near topographic escape terrain. Coupled with this analysis, I addressed concerns regarding potential negative effects of fire in this system by comparing vegetation composition of unburned habitats to burned habitats that were treated with a native seed mixture. I found that foliar cover in burned areas was on average two times greater than in unburned areas and that post-fire seeding efforts likely allowed for these differences to be proportionally similar between native and non-native grass species. My results provide an encompassing view on the effects of fire for a common management situation in which both land and wildlife values are of mutual interest.
Open Access
Modular modeling and its applications in studies of grazing effects
(Colorado State University. Libraries, 2016) Miao, Zhongqi, author; Boone, Randall, advisor; Conant, Richard, committee member; Ocheltree, Troy, committee member
Grazing is an important ecosystem process that can affect the grazing system at different levels. Overall grazing effect can be a combination of various direct and indirect effects. It is difficult to study grazing with all of the effects considered. To have a better knowledge of grazing effects and animal-plant interactions, modeling is one important pathway to achieve this goal. People usually use a diversity of approaches when modeling grazing based on different objectives, which makes model evaluations and comparisons difficult. With modular modeling, where different model components are regarded as separate and standardized modules, this situation can be changed. An example model is developed using a modular approach. It included most of the grazing effects and switches that can turn these effects on and off. This model was designed to be capable for applications with different hypothesis and objectives. It is expected to be clearer for people who are not familiar to models to make comparisons and evaluations of grazing effects. To test the feasibility of the model, a theoretical experiment on compensatory behavior in grassland production and a realistic simulation on plant-animal interactions in Qinghai-Tibetan plateau, China, are conducted. The results of these two applications demonstrate the benefits of using modular modeling in studies of grazing effects.
Open Access
Photovoice as a technique to understand the perceptions of local people neighboring Tarangire National Park in Tanzania on the risks caused by migratory animals
(Colorado State University. Libraries, 2013) Sumay, Gloria, author; Boone, Randall, advisor; Bowser, Gillian, advisor; Wittemyer, George, committee member; Bruyere, Brett, committee member
What is the impact of wildlife on communities neighboring national parks and protected areas? Understanding perceptions of risk by local communities on wildlife can help conservation efforts and the development of acceptable policies for parks and protected areas. This study examines communities along the eastern boundary of Tarangire National Park using a combination of Photovoice techniques and individual interviews to determine how these communities perceive risk from wildlife to their agriculture, livestock and economies. Here Photovoice was used to articulate participants' perception of risks to their livelihoods from migratory wildlife that transversed the national park. Three villages (Terrat, Narakauwo and Emboreet) were chosen based on their proximity to wildlife migration corridors and 12 participants from each village were asked to document their perceptions of risk from wildlife using digital cameras. Photovoice uses images taken by participants on a pre-determined topic, followed by interviews of the participants on the photographs to determine themes. In addition, twenty participants from the same villages were interviewed on their perception of risk from wildlife damage using survey questions and narratives. The characteristics of each village (size, distance from each other and distance from park boundary) were determined using GIS and satellite imaginary. The villages had different perceptions (p = 0.003) based on the three categories of risk: wildlife damage, crop damage and shared resources. Village size had no influence on the peoples' perceptions of risk; however land use patterns (farm land and associated activities) showed some influence on perceptions of risk. Changes in land use for two of the villages, Emboreet and Narakauwo, indicated a large increase in farming activities, which are likely to influence peoples' perception of risk. In Emboreet village, which has more farm land, the greatest risk was perceived as crop damage. The results of this study demonstrate the complex relationships between protected areas, migratory wildlife and community villages. To balance the needs to protect highly migratory species such as the wildebeest, conservation managers need to incorporate the perceived risks among villages and the factors that influence those perceptions.
Open Access
Predicting cattle grazing distributions: an agent-based modeling approach
(Colorado State University. Libraries, 2020) Gersie, Samuel, author; Boone, Randall, advisor; Augustine, David, committee member; Tinkham, Wade, committee member
An agent-based model was designed which simulates foraging of yearling steers grazing in the short grass steppe region of Colorado, USA. Eleven hypotheses were analyzed that address different aspects of foraging behavior. Models tracked the grazing distributions of simulated steers, as well as their time spent grazing and amount of forage consumed. Model output was validated against grazing distributions and time spent grazing of real steers, observed using GPS-collars. Results indicate that in pastures containing sufficient heterogeneity, steers exhibit selective grazing behaviors in response to forage concentration and slope, as well as use reference memory to return to higher quality patches. In relatively homogenous pastures, cattle graze evenly, and over the course of multiple grazing seasons do not exhibit the selective foraging behaviors tested in this model. Future uses of this model include applying it to other range management scenarios to address differences in steer foraging behavior and pairing the agent-based model with a more elaborate ecosystem model to analyze relationships between steers and vegetation.
Open Access
Predicting condor range expansion in California to reduce development threats
(Colorado State University. Libraries, 2020) Punzalan, Arianna, author; Boone, Randall, advisor; Aubry, Lise, committee member; Aldridge, Cameron, committee member; Ransom, Jason, committee member
Collisions with wind energy infrastructure is a major cause of wildlife mortality worldwide and especially pose threats to bird and bat populations. Avian species that have associations with habitats that generate strong winds are at higher risk of collision with wind turbines. Critically endangered California condors (Gymnogyps californianus) are among species that use areas with high-class winds. As the condor's population growth continues to face challenges, it is imperative that managers working with the California Condor Recovery Program identify and reduce all threats to the species and foster conditions that promote condor recovery. Renewable energy projects, particularly wind energy, pose risks to condors; and new developments within current, documented condor range require planning and consultation with the United States Fish and Wildlife Service. However, industrial-scale wind energy projects in California consider condor flocks in central and southern California separate and statically persisting within their current ranges. This misconception may result in development within condor habitat that is detrimental to range expansion and recovery. In this thesis, I examine factors that influence condor home range sizes, predict where condors are likely to expand their range within identified suitable habitat in California, and assess where the predicted condor range overlaps with areas that generate high-class winds preferred for wind energy development. My first chapter focuses on estimating annual home ranges of condors and identifying factors that influence home range size. Understanding what intrinsic and extrinsic variables influence condor home ranges can inform management planning and aid in predicting condor range expansion. I used location data collected from condors released in central and southern California to estimate annual condor home range area and assessed twenty-one variables related to individual characteristics, management factors, population dynamics, and habitat suitability to identify strong predictors of home range size. I found that age group, time spent in the wild, age of managing agency, maximum slope, maximum NDVI, distance to water, and road density were significant predictors of annual home range area. On average, adult breeding condors had the smallest home range areas and subadult condors had the largest home range areas. Population size did not affect annual home range size of condors; however, home range size increased the longer a managing agency had been releasing condors. My objective of the second chapter was to predict condor range expansion in California and identify where there may be conflict between condors and potential wind energy development. Predicting condor range expansion may inform managers of areas to concentrate efforts and resources for management and outreach, as well as identify areas that should be considered during wind energy development planning stages to reduce risks to condor recovery. I used the results from Chapter 1 and a habitat suitability surface to create a tool in which a user can customize the demographics of condor flocks in California sometime in the future and predict the overlapping home ranges of individuals in the flocks. Users can then export the predicted ranges into a GIS program to consider how the overlapping home ranges may be affected by plans for wind energy development and identify possible alternative sites. I predicted condor range expansion in California under four scenarios: 1) population size and structure stays the same (2019 California population); 2) each flock has 150 individuals with 15 breeding pairs; 3) each flock has a majority of breeding pairs, which maximizes breeding pairs and minimizes sub-adult condors; and 4) each flock has a majority of subadults, which maximizes subadult condors and minimizes breeding pairs. Predicted ranges under different scenarios exhibited high similarity and areas with high-class wind generation overlapped with <10% of predicted condor range under all scenarios. More than 81% of areas with strong winds suitable for energy generation were unaffected by predicted condor range, suggesting there are alternative areas for wind energy development with less risk of conflict with critically endangered California condors.