Thesis (Ph. D.)--University of Michigan, 1942. / Cover title. "Literature cited": p. 118-121.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 182-190). Also available via the Internet.

Thesis (doctoral)--Vereinigte Friedrichs-Universität Halle-Wittenberg. / Vita. Includes bibliographical references ([9]-10).

Thesis (M.S.)--University of Wisconsin--Madison, 1947. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

A field survey to investigate the ecology of cardio-vascular disease in free living wild animals is described. Its aim was i) to assess the susceptibility of such animals to arteriosclerosis. and particularly to athero-sclerosis ii) to examine in greater detail the ecology of oardiovascular disease in a single, naturally-susceptible species in relation to dietary change and stress in naturally occurring situations. A total of 201 specimens, representing species of mammals and 25 of birds, was examined: 37 species of mammals had uncomplicated lipid deposits in the arterial intima, thought to represent a normal physiological occurrence; 13 had atheroma-like lesions of the intima; 20 species of birds shoved positive lipidosis. These findings. compared with those reported in taxonomioally equivalent groups of captive animals, are discussed. The African elephant was selected for special study. The eoology of its cardiovascular disease patterns was studied in three different habitat types: one natural (the 'control'). and two degenerate ('stressed'). Athero-sclerosis and medial sclerosis were found not to occur in the 'natural' habitat type, but to be directly correlated with habitat degeneration in the other two 'stressed ranges, where 'stress' factors included excessive exposure to sunlight, dietary changes, frustration of the migrator/ habit, disrupted calving patterns9 and over-population neither disease was found to be directly related to age, and each had a distinct intra-arterial development patterns the aetiology of each is therefore thought to be basically independent, although in advanced cases interaction may occur. Incidental results of the survey includes i) observations on the importance of relating the functional anatomy of the arterial supportive thickenings at ostia, bifurcation and regions of mechanical strain to the normal intra-aortic distribution of uncomplicated intimal lipid deposits; ii) observations on a valve-like structure in the aorta of the klipspringer; and iii) the formulation of a new field technique for assessing relative age in the African elephant.

<p> Rivers in semi-arid regions are highly sensitive and pressured yet can support diverse assemblages of species. In central New Mexico, the Rio Grande (River) is the lifeblood of the Middle Rio Grande Valley (MRGV), a semi-arid region which maintains large urban and agricultural centers and is also the principal wintering area for the Rocky Mountain Population of greater sandhill cranes (<i>Antigone canadensis tabida</i>). Human-induced environmental change has transformed the MRGV and habitat availability prompting concerns for the population. To address these concerns, I investigated dietary and behavioral responses of sandhill cranes to the collection of features that function as winter habitat. In Chapter 1, I demonstrated a novel application of stable isotopes to evaluate dietary reliance of sandhill cranes on corn subsidies provisioned by natural resource agencies, estimated rates of carbon isotope incorporation in tissues of sandhill cranes, and estimated tissue-derived winter arrival dates of sandhill cranes. I found subsidized corn was the primary dietary component of sandhill cranes, rates of carbon isotope incorporation in sandhill crane tissues differed predictably by metabolic activity, and estimated tissue-derived arrival dates on wintering grounds approximated actual arrival dates. In Chapter 2, I advanced a hierarchical Bayesian framework for overcoming challenges and improving analysis of behavioral data frequently generated in animal behavior studies and used behavioral observations of sandhill cranes as a case study. In Chapter 3, I estimated energetic and temporal availability of corn subsidies and seasonal energy requirements of sandhill cranes. I found seasonal energetic requirements of the population are likely satisfied by corn subsides but not without strategic planning. In Chapter 4, I examined how current landscape and riverine configuration influenced patterns of diel habitat selection by sandhill cranes. Sandhill cranes avoided sources of anthropogenic disturbance, relied heavily on managed public land resources, and selected roosting locations in the Rio Grande with a wider channel, interspersion of sandbars and shallow water, and low channel bank vegetation. My research suggests sandhill cranes have coped with alterations that have led to current conditions in the MRGV, however, habitat-related resources will need to be managed adaptively as drivers of environmental change will undoubtedly influence future circumstances. </p><p>

abstract: 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. / Dissertation/Thesis / Masters Thesis Applied Biological Sciences 2016

<p> Southern flying squirrels (SFS; <i>Glaucomys volans</i>) are known kleptoparasites on the endangered red-cockaded woodpecker&rsquo;s (RCW; <i> Picoides borealis</i>) cavities and cost land managers time and money to control, and the ecology of SFS in habitats managed for RCWs is poorly understood. This study is designed to obtain a better understanding of the general ecology of SFSs surrounding RCW habitat and provide possible non-lethal deterrent methods to prevent harmful interactions between SFSs and RCWs. Spatially-explicit capture-recapture showed generally higher SFS densities and habitat associations outside of RCW cluster partitions. Stable isotope analysis of SFS diets across Mississippi and Alabama revealed a narrow dietary breath relative to food items, thus habitat management may still be viable option to control SFSs. Lastly, investigation of odor deterrents resulted in the greatest avoidance of cavities containing gray rat snake (<i>Pantherophis spiloides </i>) feces and warrants further investigation.</p><p>

<p> Several state, federal and non-profit agencies have developed collaborative goals for restoring habitat in New England and New York for a declining rabbit species, the New England cottontail (<i>Sylvilagus transitionalis</i>, NEC). My goal was to evaluate habitat restorations at both the local, or site, scale, and the landscape scale. In order to objectively quantify the suitability of the sites being managed, I developed a Habitat Suitability Index, based on the HSI models designed the U.S. Fish and Wildlife Service. I identified candidate habitat variables for NEC, including types of cover and refuges, and food, and then asked a panel of NEC experts to rank the importance of the candidate variables. I collected data on the most important habitat variables at 60 sites managed for NEC across New England and eastern New York. The NEC experts also ranked the same 60 sites from 1 (unsuitable) to 5 (optimal). The model was optimized to improve agreement with expert opinions for the 60 sites. Specific applications may include determining when a site is suitable for releasing translocated or captive breed rabbits, and identifying habitat features that need modification as forest succession progresses. To evaluate habitat restoration efforts at a larger landscape scale, I created metapopulation models for two management focus areas (Cape Elizabeth and Kittery-Berwick) in Maine for population viability analyses. I ran simulations to compare the relative effects of the two focus areas as well as five management scenarios. I conducted a sensitivity analysis to determine the importance of various model parameters on extinction risk. The Cape Elizabeth focus area, which has more habitat patches that are closer together, had lower extinction risks than Kittery-Berwick. Reintroductions and creating additional habitat appeared especially important in the Kittery-Berwick focus area. The simulation results were sensitive to changes in the standard deviations of the survival and recruitment rates, and the probability of catastrophic mortality, indicating that variation is detrimental to NEC metapopulation growth. Variation in weather caused by climate change may need to be mitigated by monitoring and managing NEC habitat and populations.</p><p>

<p> Habitat loss and the resulting fragmentation can alter animal movements and disrupt animal seed dispersal mutualisms; however, these effects on spatial patterns of seed dispersal are not well understood. To explore the effects of habitat loss and fragmentation on seed dispersal distances and seed dispersion (aggregation), I created a spatially-explicit, individual-based model of an animal dispersing seeds (SEADS &ndash; Spatially-Explicit Animal Dispersal of Seeds). For Chapter 1, I ran SEADS in a theoretical landscape of 0-90% habitat loss to determine the effects of habitat loss on three animal traits relevant to seed dispersal: movement distance, gut retention time, and time between movements. SEADS results revealed a complex interaction involving all animal traits and habitat loss on dispersal distances and dispersion, driven by a novel underlying mechanism of fragment entrapment. Unexpectedly, intermediate habitat loss could increase dispersal distances and dispersion relative to low and high habitat loss for some combinations of animal traits. In Chapter 2, I developed a new method (TriAD) to estimate animal locations from triangulation data to improve triangulations for toucans. Location estimates calculated with TriAD averaged 23-63 m closer to true locations for three of four distance classes compared to the traditional method (Lenth&rsquo;s maximum likelihood estimator, LMLE). Additionally, over 99% of 570 triangulations converged for TriAD compared to 85.8% for the LMLE. For toucan data, 98.0% of 4445 triangulations converged in TriAD compared to 88.6% for the LMLE. In Chapter 3, I parameterized SEADS with data from toucan movements and gut retention trials collected in Costa Rica to evaluate the effects of landscape, body size, and social organization on seed dispersal. The larger, less social species dispersed seeds 17-28% farther and in less aggregated patterns than the smaller, social species. This pattern was driven by longer movements in the larger species, suggesting that body size is more important than social organization for seed dispersal in our system. Habitat use and home range sizes limited dispersal distance and dispersion for both species. Findings from our simulations illustrate the importance of separating and quantifying the effects of disperser behaviors and landscape effects that shape seed deposition in fragmented areas.</p><p>