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Movements, habitat selection, and home ranges of greater sandhill cranes (Grus candensis tabida) in OhioTucker, Jason Todd January 2014 (has links)
No description available.
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Population Ecology of Badgers (Taxidea taxus) in OhioDuquette, Jared F. 07 October 2008 (has links)
No description available.
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Summer Ecology of the Indiana bat (<i>Myotis sodalis</i>) in an Agricultural LandscapeKniowski, Andrew Broni 21 March 2011 (has links)
No description available.
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Spatial Ecology of a Vulnerable Species: Home Range Dynamics, Resource Use, and Genetic Differentiation of Eastern Spotted Skunks in Central AppalachiaThorne, Emily D. 28 April 2020 (has links)
The spatial distribution of a species is not random or uniform across all landscapes, nor is it independent of resource availability and risk of predation. A key aspect in the study of wildlife ecology is understanding how a species evaluates its surroundings and selects habitat that offers advantages to survival and reproductive success. In theory, an individual should select habitat that offers adequate resources to meet its biological requirements and allows it to adjust its use of resources based on a variety of abiotic and biotic habitat factors. Relationships between wildlife populations and habitat characteristics are difficult to assess, yet identification and characterization of these relationships can improve delineation of limiting habitat factors needed for effective conservation and management. The eastern spotted skunk (Spilogale putorius) is a small Mephitid (weasel family) that was once a fairly common furbearer throughout the central and southern United States, with annual range-wide harvests of over 100,000 individuals. In Virginia, the spotted skunk is classified as vulnerable, and anecdotal evidence suggests that this species has been rare or largely absent from the central and southern Appalachians over the last two decades. Limited knowledge of spotted skunk habitat associations in Virginia dictate the need for research on this species of concern. The aim of this study was to determine the associations of environmental characteristics ofwith spotted skunk habitat selection and genetic differentiation. I assessed first-order habitat selection by conducting an analysis of predicted occurrence at the landscape scale. Next, I assessed second- and third-order selection using resource utilization functions to determine habitat selection among, and within, home ranges. Further, I assessed fourth-order selection by identifying microhabitat selection and resource use at spotted skunk den site. Finally, I evaluated genetic diversity and population structure of spotted skunks in the Appalachian Mountains. I found that spotted skunk habitat is distributed in small, spatially disjunct patches and that movement, home range size, and resource selection are impacted by availability of habitat and the isolation and/or fragmentation of this suitable habitat. I found overall low genetic diversity and evidence of inbreeding within populations and geographic patterns of genetic differentiation with distinct subpopulations isolated by unsuitable landscape characteristics. Application of these results will contribute to more effective conservation of eastern spotted skunks throughout the Appalachian Mountains. / Doctor of Philosophy / Wildlife species do not occur throughout the landscape randomly or evenly, but rather choose their locations based on the availability of food, cover, and water. A key aspect in the study of wildlife ecology is understanding how a species chooses its natural surroundings and selects habitat that allows it to survive and reproduce. In theory, an animal should choose a location that offers enough resources, such as food, cover, and water to meet its biological needs and allows it to adjust based on access to these resources. By understanding the how the availability of these resources influences an animal's choice of location, wildlife managers can better determine the need for protection or management of the species in a given area. The eastern spotted skunk (Spilogale putorius) is a small, weasel-like animal that was once fairly common throughout the central and southern United States. In Virginia, the spotted skunk is a protected species, and experts suggest that it has been rare in the central and southern Appalachians for over several decades. Because there is limited knowledge of spotted skunk habitat needs in Virginia, research on this species is necessary. The goals of this study were to determine the type of habitat in which spotted skunks are choosing and how it affects the species genetic makeup. First, I determined in which general areas spotted skunks exist in Virginia. Next, I determined that the habitat for spotted skunks includes forests with ample bushy plants and rocks to hide from predators. I then examined the genetics of spotted skunks to determine relatedness among individuals and whether inbreeding was occurring. Finally, I compared the relatedness of pairs of spotted skunks to the distance between their locations and found that skunks that are located on the same mountain range are more closely related to each other than to skunks on different mountain ranges. These results will inform wildlife managers on how to provide spotted skunks with the habitat resources they need to survive and reproduce successfully, thus promoting skunk conservation.
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Assessing Habitat Quality for the Endangered Red-cockaded WoodpckerConvery, Ken 13 January 2003 (has links)
This project had 2 major objectives. The first objective was to assess how well the revised U.S. Fish and Wildlife Service Foraging Habitat Guidelines depict good quality habitat for the red-cockaded woodpecker (Picoides borealis) at Camp Lejeune, NC. To accomplish this, I used multiple linear and logistic regression to examine the relationships between fitness, habitat use, home range size, and habitat characteristics described in the guidelines. I assumed that habitat characteristics that confer quality were related to higher fitness, greater habitat use, and reduced home range size. To a large extent, the guidelines are validated. Red-cockaded woodpeckers responded favorably to habitat that mimics the historical, mature, and fire-maintained pine forests of the southeastern U.S., characterized by high densities of large pines, low densities of small and medium pines, and a lush herbaceous groundcover. Variables positively associated with habitat use and fitness were associated with reduced home range size, and those negatively associated with habitat use and fitness with increased home range size. Percent herbaceous groundcover was a significant regressor indicative of quality in every model. The second objective was to assess how well USFWS foraging partitions represent habitat used by red-cockaded woodpeckers. I conducted home range follows of 23 groups of red-cockaded woodpeckers and estimated the percentage of each home range encompassed by partitions of varying radii. The percentage of the actual home range included in the partition increased as a function of partition radius. The standard 800 m circular partition, on average, included 91% of the home range, but significant variation existed between groups. / Master of Science
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Annual Survivorship and Movement Ecology of Migrant American Kestrels (Falco sparverius) Overwintering in North TexasKaleta, Madeleine Grace 05 1900 (has links)
American Kestrels (Falco sparverius) are a small falcon with an expansive range across North America. However, kestrels have been reported to be declining since the 1960s, with the primary cause of decline unknown. With previous research focusing on the summer breeding season, researchers have called for additional investigation in understudied wintering and migratory periods. In Chapter 2, I quantified annual survivorship against five covariates of migrant kestrels wintering in north Texas to contribute to population level analyses across the kestrel's expansive range. Notably, I found that juvenile survival is similar to that of adults once on the wintering grounds, and that aspects of urbanization may increase survival in wintering kestrels. In Chapter 3, I outlined kestrel movement ecology by quantifying migration phenology, performance, and patterns. Additionally, I identified breeding and stopover sites and analyzed both winter and summer home ranges. In this analysis, I contributed three additional migration tracks to the five currently published. Further, I reported the first loop and indirect migration patterns to our knowledge. Overall, this research highlights understudied aspects of the kestrel full annual cycle in the winter and migratory periods, providing insight into possible causes for kestrel declines.
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Determining Habitat Associations of Virginia and Carolina Northern Flying Squirrels in the Appalachian Mountains from Bioacoustic and Telemetry SurveysDiggins, Corinne Ashley 23 August 2016 (has links)
The Virginia northern flying squirrel (Glaucomys sabrinus fuscus) and the Carolina northern flying squirrel (G. s. coloratus) are geographically isolated subspecies of the northern flying squirrel found in montane conifer-northern hardwood forests the Appalachian Mountains of the eastern United States. Both subspecies were listed under the Endangered Species Act in 1985 as endangered, and accordingly, the Virginia northern flying squirrel and the Carolina northern flying squirrel are considered high conservation priorities by state and federal agencies. Although the listing prompted work to determine the broad distribution and habitat associations of both subspecies, numerous data gaps remain, particularly with regard to habitat management and development of efficient monitoring techniques. Regional interest in restoration of red spruce (Picea rubens) forests in the central and southern Appalachian Mountains, considered to be the flying squirrels' primary habitat, increases the importance of understanding habitat selection and managers' ability to detect squirrels at multiple spatial and temporal scales.
I compared two novel survey techniques (ultrasonic acoustics and camera trapping) to a traditional technique (live trapping) to determine which method had higher probability of detection (POD) and lower latency to detection (LTD, number of survey nights to initial detection) of northern flying squirrels in the region. Both novel techniques performed better than the traditional techniques with higher POD and lower LTD. I found that ultrasonic acoustics and camera trapping had similar POD, whereas LTD was significantly lower with ultrasonic acoustics versus camera trapping. Additionally, the ability to distinguish between northern flying squirrels and the parapatric southern flying squirrel (G. volans) also is possible with ultrasonic acoustics, but not with camera trapping. This ultimately makes ultrasonic acoustics the most effective and efficient method to obtain detection/non-detection data. To better inform management decisions and activities (i.e., red spruce restoration), this method should be used in conjunction with existing traditional monitoring techniques that provide demographic data such as nest boxes.
I assessed habitat selection of radio-collared Virginia and Carolina northern flying squirrels at multiple spatial scales with use-availability techniques. I analyzed field data from paired telemetry and random points and determined Virginia northern flying squirrels microhabitat (within-stand habitat) selection showed preference for conifer-dominant stands with deep organic horizons, a factor that might be directly linked to food (hypogeal fungi) availability.
Similar to previous studies on the Virginia northern flying squirrel on the landscape- and stand-level using Euclidean distance based analysis, Carolina northern flying squirrels also selectively preferred montane conifer forests in greater proportion than their availability on the landscape. Additionally, Carolina northern flying squirrels did not select for or against northern hardwood forests regardless of availability on the landscape. Habitat preference of both subspecies indicates that red spruce restoration activities may be important for the persistence of Appalachian northern flying squirrels into an uncertain future, as anthropogenic climate change may cause further reduction of the quality and extent of high-elevation montane conifer forests in the region. / Ph. D.
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The Habitat Ecology of Bog Turtles (<i>clemmys Muhlenbergii</i>) in Southwestern VirginiaCarter, Shawn L. 07 August 1997 (has links)
I radiotracked 31 bog turtles (<i>Clemmys muhlenbergii</i>) from May 1995 to December 1996 at 4 study areas in southwestern Virginia. Radio location data were used to provide measures of annual activity, spatial distributions of animals, and habitat selection. The techniques I used in this study were as follows: distance measurements between consecutive locations, home range estimators (Minimum Convex Polygon [MCP] and cluster analysis), compositional analysis of habitat selection, and measurement of microhabitat variables.
Results suggest a random pattern of movement by bog turtles within habitats. Average net movements recorded between consecutive locations (separated by < 7 days) during 1995 and 1996 measured 15 m and 20 m for females and 14 m and 23 m for males respectively. Eighty-six percent of all net movements (n = 824) were less than 30 m, whereas only 2% were greater than 100 m. In 1996, average home range sizes (95% MCP, 95% cluster) were 0.47 ha and 0.17 ha for females and were 0.57 ha and 0.13 ha for males. Bog turtles selected wet meadow areas and bulrush (<i>Scirpus</i> spp.) patches more than expected randomly and avoided dry meadow areas and streams. Turtles were located more frequently in mud (x = 24.3 cm) and water (x = 5.2 cm) than expected by random selection (P < 0.001). I found no differences between sexes in movement, home range, or habitat selection by bog turtles.
Bog turtles select specialized habitat types and microhabitats within wetlands. Large-scale movements are infrequent and the risk of site isolation may be high if wetland habitat loss continues at historic rates. Future management should protect spatially-close sites which contain multiple habitat types, soft substrate, and pockets of water. / Master of Science
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Space Use, Microhabitat and Macrohabitat Use of the Three-Toed Box Turtle (Terrapene carolina) in North TexasJoseph, Sara A. 12 1900 (has links)
Box turtle (Terrapene carolina) populations are steadily declining due their unique natural history, effects of climate change, and anthropogenic land use change. There is a need for updated information on box turtle space and micro and macro-habitat use to inform conservation efforts. This study used VHF radiotelemetry and GPS data loggers to examine box turtle space and habitat use in North Texas. Box turtle home range sizes averaged 6.6ha (range = 0.79 - 18.08, n = 23), and males (n = 9) had larger home ranges than females (n = 14; W = 31.5, P = 0.05). Home range size was best explained by a combination of variables including sex and body size, but overall, home ranges that consisted of higher percentages of suitable box turtle habitat were smaller. Box turtles used deciduous forest more than expected and wetlands less than expected by chance (Fisher's exact test, P < 0.0001). The most informative variable for box turtle macrohabitat selection was NDVI. Box turtles selected microhabitats with a higher percent litter (t = -2.16, P < 0.05) and understory cover (t = -5.03, P < 0.05). The results of CART analysis showed the nested importance of macro- and microhabitat and identified NDVI as the most important variable for predicting suitable box turtle habitat. Given these results, we postulate that NDVI can be used to identify suitable box turtle habitat at landscape scales to aid in management and conservation efforts. We found that three-toed box turtles are using habitat differently than what has been reported in eastern box turtles, providing support for the theory that three-toed box turtles should be classified as a separate species.
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Analyse der Tier-Umwelt-Interaktionen bei Yaks (Bos grunniens) im kirgisichen HochgebirgeTolobekova, Aijan 18 October 2019 (has links)
Yaks sind sehr gut an die Umweltbedingungen des kirgisischen Hochgebirges angepasst und sind seit Jahrhunderten ein Bestandteil dieses Ökosystems. Politische und wirtschaftliche Veränderungen haben in den letzten 60 Jahren dazu geführt, dass die Yakbestände in Kirgistan zurückgegangen sind. Seit einigen Jahren gibt es Bestrebungen diese wiederaufzubauen. Dabei müssen die ökologischen Ansprüche der alpinen Landschaft berücksichtigt werden. Das Ziel der Arbeit bestand darin, in einem engen zeitlichen Raster, das Verhalten der Yaks im Herdenverband zu analysieren, die Lebendmasseentwicklung von Yakfärsen im Zusammenhang mit dem saisonalen Einfluss zu untersuchen und den Weideertrag zu schätzen. Dazu wurden im Osten Kirgistans Verhaltensuntersuchungen an 12 Yakkühen durchgeführt sowie die Lebendmasseentwicklung von 20 Yakfärsen analysiert. Für die Analyse der Vegetation wurden 10 Plots genutzt.
Das Habitatsverhalten der Yaks ist von verschiedenen Faktoren abhängig, die vor allem im Zusammenhang mit dem großen Weidegebiet stehen: die Variation im Futterangebot, die geografischen Gegebenheiten sowie die Witterungsverhältnisse. Die Untersuchungen zeigten, dass das Verhalten der Yaks stark durch die Jahreszeiten beeinflusst wird. Das bezieht sich auf die Nutzung von Flächen und Höhenlagen sowie auf das Bewegungsverhalten. Es zeigte sich, dass bestimmte Weideareale permanent stärker frequentiert werden. Die Lokomotion der Yaks ist im Winter stärker ausgeprägt als im Sommer. Die Vegetationsanalyse weist darauf hin, dass Ertrag und Futterwert der Weidepflanzen, eindeutig durch die Höhenlage beeinflusst werden. Die Untersuchungen zur Lebendmasseentwicklung zeigten den gravierenden Einfluss der Jahreszeiten und damit des Futterangebotes auf die Lebendmasseentwicklung der Yakfärsen.
Ein detailliertes Wissen über das Verhalten von Yaks kann dazu beitragen, die Bewirtschaftung von Hochgebirgsweideflächen zu verbessern und vorhandene Ressourcen schonend und nachhaltig zu nutzen. / Yaks are very well adapted to the environmental conditions of the Kyrgyz high mountains and have been part of this ecosystem for centuries. Political and economic changes over the past 60 years have led to a decline in yak stocks in Kyrgyzstan. For some years, there have been efforts to rebuild them, to this end the ecological demands of the alpine landscape must be taken into account.
Within this context, the objectives of the PhD – thesis were to analyse the behaviour of the yaks in the herd, to investigate the development of the body weight of yak heifers in connection with the seasonal influence and to estimate the grazing yield in a tight time grid. In the eastern part of Kyrgyzstan, 12 yak cows were selected for the behavioural studies and 20 yaks heifers for the development of the body weight. For the analysis of the vegetation, 10 plots were used.
The habitat behaviour of the yaks depends on various factors, which are mainly related to the large grazing area: the variation in the forage supply, the different geographical conditions as well as the weather conditions. The investigations showed that the behaviour of the animals is strongly influenced by the seasons, specifically regarding use of areas and altitudes; as well as to exercise behaviour. It was found that certain pastures are permanently more frequented than others. The locomotion of the yaks is more pronounced in winter than in summer. The research on the development of the body weight showed the serious influence of the seasons and thus of the food supply on the development of the yak heifers. Results showed that body growth takes place despite the losses in winter. The vegetation analysis indicates that the yield and feed value of the pasture plants are clearly influenced by the altitude.
A detailed knowledge of the behaviour of yaks can help to improve the management of high mountain pastures and thus to use the available resources sparingly and sustainably.
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