Matching Items (3)
Description
An understanding of diet habits is crucial in implementing proper management strategies for wildlife. Diet analysis, however, remains a challenge for ruminant species. Microhistological analysis, the method most often employed in herbivore diet studies, is tedious and time consuming. In addition, it requires considerable training and an extensive reference plant collection. The development of DNA barcoding (species identification using a standardized DNA sequence) and the availability of recent DNA sequencing techniques offer new possibilities in diet analysis for ungulates. Using fecal material collected from controlled feeding trials on pygmy goats, (Capra hicus), novel DNA barcoding technology using the P6-loop of the chloroplast trnL (UAA) intron was compared with the traditional microhistological technique. At its current stage of technological development, this study demonstrated that DNA barcoding did not enhance the ability to detect plant species in herbivore diets. A higher mean species composition was reported with microhistological analysis (79%) as compared to DNA barcoding (50%). Microhistological analysis consistently reported a higher species presence by forage class. For affect positive species identification, microhistology estimated an average of 89% correct detection in control diets, while DNA barcoding estimated 50% correct detection of species. It was hypothesized that a number of factors, including variation in chloroplast content in feed species and the effect of rumen bacteria on degradation of DNA, influenced the ability to detect plant species in herbivore diets and concluded that while DNA barcoding opens up new possibilities in the study of plant-herbivore interactions, further studies are needed to standardize techniques and for DNA bar-coding in this context.
ContributorsMurphree, Julie Joan (Author) / Miller, William H. (Thesis advisor) / Steele, Kelly (Committee member) / Salywon, Andrew (Committee member) / Arizona State University (Publisher)
Created2012
Description
ABSTRACT Over the past several decades, the dilemma of free-roaming horses in the U.S. has proven to be one of the most divisive issues in management of public lands. According to federal land management agencies, without population regulation, horses can increase at the rate of 15-20% a year on arid rangelands with inadequate numbers of natural, large predators. Horses compete for valuable forage and water resources alongside cattle and native wildlife in delicate riparian areas highly susceptible to the negative ecological effects of soil compaction and overgrazing. Most U.S. management policies, therefore, call for increased removal of free-roaming horses as they are categorized as “un-authorized livestock” or "non-native" species. Wild horse advocates, however, continue to petition for improvement in animal welfare and expansion of the horses’ territory. With heightened social conflict spurred by animal rights and ecological concerns, not to mention the often-stark differences over what really “belongs” on the landscape, the success of appropriate management strategies hinges on managing agencies’ preparedness and ability to respond in a timely and inclusive manner. A critical element of the management context is the public’s views toward the wild horse and the science used to manage them. Synthesizing the vast literature in the history and philosophy of wildlife management in the American West, and utilizing an ethnographic and case study approach, my research examines the range of stakeholder concerns and analyzes the factors that have led to the disconnect between public values of wild horses and public policy for the management of the federally protected free-roaming horses in Arizona’s Apache-Sitgreaves National Forests.
ContributorsMurphree, Julie Joan (Author) / Minteer, Ben A. (Thesis advisor) / Schoon, Michael (Thesis advisor) / Bradshaw, Karen (Committee member) / Chew, Matthew (Committee member) / Arizona State University (Publisher)
Created2022
Description
The National Wilderness Preservation System (NWPS) is a collection of more than 800 areas designated as wilderness under the Wilderness Act of 1964. The Act defines wilderness as an “area where the earth and its community of life are untrammeled by man, where man himself is a visitor who does not remain.” Wilderness lands are supposed to be pristine examples of nature where the overseeing agency has not allowed any post-designation development. The language of the act describes land designated as wilderness as “untrammeled” by people, discounting thousands of years of human influence. It also discounts the potential effect of surrounding lands and visitors on the wilderness. The management of these lands falls to all four federal land management agencies, and they each had – and still have – their own organizational perspectives on the Wilderness Act and their agency’s role in its implementation. Although the Act provided criteria for designating and managing wilderness, concrete guidance is lacking. This ambiguity has allowed a rift to emerge between those who believe that wilderness should be actively managed and those who believe that wilderness should be preserved and left alone as much as possible. The diversity of views and agency approaches have created administrative divides between wilderness lands and other land types. In parallel, the introduction of subsequent environmental laws have placed additional legal boundaries on the land, creating parcels next to and within wilderness that are subject to different uses and requirements. This study, which marshals dozens of expert interviews and explores a series of wilderness cases across the United States, focuses on several unanticipated challenges of stewarding the NWPS in the 21st Century. These include: the impacts of public land parceling due to legal obligations; how statuary ossification affects current interpretations of the various laws bearing on wilderness lands; and ultimately how land managers and agencies – who are looking toward a future of increased anthropogenic impacts on wildlife biodiversity and endangered/threatened species on wilderness lands – approach these challenges.
ContributorsFacemire, Challie Renee (Author) / Minteer, Ben A (Thesis advisor) / Ellison, Karin (Thesis advisor) / Bradshaw, Karen (Committee member) / Hahn, Beth (Committee member) / Budruk, Megha (Committee member) / Arizona State University (Publisher)
Created2022