Movement patterns of animals are varied, complex, and can be influenced by environmental and anthropogenic factors. One form of animal movement, migration, is influenced by environmental factors that alter the timing, duration, intensity, and likelihood of migration. Additionally, features of the landscape, both natural and anthropogenic, can alter how animals move through their seasonal and home ranges. Movement patterns can be impeded or prevented by features such as railroads, rivers, and roads. Here we explore characteristics of elk (Cervus canadensis) migration by evaluating the strategies of migration exhibited and the factors that influence migration of elk in central and eastern Utah. In addition we determine landscape features that act as barriers to movement of elk. In the first chapter, we characterize migration of elk, and examine the influence of environmental factors have on the propensity and intensity of migration. In the second chapter, we determine barriers to movement and if the identified barriers could be better used as management area boundaries.

Thesis (Ph. D.)--Miami University, Dept. of Botany, 2004. / Title from second page of PDF document. Includes bibliographical references (p.70-79).

Estimates of abundance are critical to manage and conserve waterfowl and their habitats. Most surveys of wintering waterfowl do not use probability sampling; therefore, development of more rigorous methods is needed. In response, I designed and evaluated an aerial transect survey to estimate abundance of wintering ducks in western Mississippi during winters 2002?2004. I designed a probability-based survey using stratified random and unequal probability sampling of fixed-width transects. To correct for visibility bias inherent in aerial surveys, I conducted an experiment to model bias and incorporated correction factors into estimation procedures to produce adjusted estimates. Bias-corrected estimates were most accurate. Precision of abundance estimates of total ducks met a priori goals (CV ≤ 15%) in 10 of 14 surveys. Based on a simulation study, the implemented survey design provided the most precise estimates, yet certain refinements remained possible. I also illustrated potential applications of survey results in the context of conservation and management of wintering waterfowl populations and habitats. I described patterns of abundance within and among winters, including a comparison with surveys conducted during winters 1988?1990 that revealed mallard abundance decreased 65% from the late 1980s. I developed a method to illustrate population abundance spatially for scientific and public education. I attempted to explain temporal variation in abundance estimates relative to variables potentially representing hypotheses explaining regional distributions of ducks. I concluded the data provided stronger support for factors related to energy conservation by ducks than factors related to energy acquisition. Finally, I determined associations between duck distributions and habitat and landscape features in accordance with the habitat-complex conceptual model. Landscapes with greater interspersion and diversity of wetlands attracted increased numbers of ducks, a though other factors such as wetland area also were important. I concluded that this study advanced methodologies to survey wintering waterfowl. Although improvements were warranted, I recommend this survey design for continued monitoring of wintering ducks in western Mississippi. Furthermore, I suggest habitat management on public and private lands should include complexes of seasonally flooded cropland, moist-soil, forested, and permanent wetlands to potentially increase wintering duck numbers in western Mississippi.

The cadastral district of Čejkovice was chosen for mapping of landscape features. The district is located approximately 9 km to the north-west of České Budějovice on a surface of 955 hectares. The following materials were used to map the territory in question ? the plan of the Territorial System of Ecological Stability and the orthophotograph map available at geoportal.gov and historical aerial photos from the Military Geographical and Hydrometeorological Institute of Dobruška. The incidence and representation of individual features were ascertained during mapping of the territory and the features were categorized. The categorization serves to process the results ? to evaluate the frequency and surface (length) of the features and at the same time to compare the present status with the status of the 1950?s. The GIS (Geographic Information Systems) software program was used to evaluate the results. At present, 38 landscape features can be found in the territory of Čejkovice (1 watercourse, 9 ponds, 4 woods, 8 woody plant groups, 9 alleys and 7 solitary plants. In 1950?s, 29 features could be found in the territory (1 watercourse, 10 ponds, 3 woods, 6 woody plant groups, 8 alleys and 1 solitary plant). The solitary plants have experienced the greatest difference ? increase by 6 plants. The surface of ponds has been increased as compared to the past status and the surface of woods has grown as well. The condition of the features does not differ too much as compared to the past condition. The most landscape features have experienced growth of surface.

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En intégrant cette étude dans un contexte d'écologie du stress, l'objectif général de cette thèse est d'une part d'évaluer l'exposition et les effets des éléments traces métalliques (ETMs)et du parasitisme chez le mulot sylvestre (apodemus sylvaticus) et d'autre part de contribuer au développement de marqueurs d'exposition et d'effets toxiques non létaux. Au cours de trois sessions de capture, des individus ont été collectés dur 30 sites localisés autour de l'ancienne fonderie de Metaleurop (Nord-Pas-de-Calais) les concentrations en Cd et Pb ont été mesurées dans les organes cibles (foie et reins) et dans les poils des mulots. différents biomarqueurs d'effets toxiques létaux et non létaux ont également été mesurés. Le nombre important de mulots prélevé (n=886) a permis d'étudier l'influence des caractéristiques individuelles (âge et sexe) et des caractéristique paysagères sur les réponses des biomarqueurs. Les résultats indiquent que les concentrations en ETMs des animaux vivants sur les sites les plus contaminés s'avèrent significativement plus importantes que celles mesurées sur les autres sites. En outre, plus de 25% des mulots provenant des sites des plis pollués présente des concentrations supérieures aux seuils toxiques et ont donc un risque accru de développer des pathologies (œdème, cancers). Par ailleurs, cette étude révèle également que ETMs chez le mulot est influencée par les caractéristiques, individuelles (âge et sexe), par l'occupation des sols et qu'elle varie en fonction de la session de capture. De plus, les résultats montrent que les concentrations ETMs [...] et les caractéristiques paysagères modulent les prévalences de certains parasites. En effet, la richesse parasitaire augmente chez les individus les plus exposés aux ETMs. Ces concentrations influencent également les différents biomarqueurs d'effets létaux [...] et non létaux [...]évalués. Ces résultats illustrent donc l'intérêt du développement de biomarqueurs on létaux pour l'évaluation des effets toxiques des ETMs les plus élevées présentent des atteintes au niveau individuel [...] et au niveau cellulaire [...] Cependant, étant donnés les effets potentiels de parasitisme sur la santé de la faune sauvage, les liens de causalité entre la présence d' ETMs et les atteintes observées sont discutables. Ce travail de thèse souligne l'intérêt des approches multi-stress dans le cadre de l'évaluation de la santé de la faune sauvage. / By integrating this study in a stess-ecology Framework, the aim of this thesis is to assess exposure and effects of trace metals (TMs) and parasitism on wood mouse[…] and to contribute to the development of non-lethal exposure and toxicity makers […].This study also reveals that the accumulations of the TMs in wood mice is influenced by individual characteristics […] and landscape features and varies according to the trapping session. In addition, results show that the concentrations of TMs […] and landscape characteristics modulate the prevalence of some parasites. […].However, given the potential effects of parasitism on animals’ health, the causal links between the presence of TMs and observed alterations are questionable. This work emphasizes the importance of multi-stress approaches on wildlife’s health assessment.