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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Land-use and socio-spatial organization of female leopards in a semi-arid wooded savanna, Botswana

Steyn, V, Funston, PJ 30 September 2009 (has links)
Abstract Leopards (Panthera pardus) are the most widespread large felid, yet comparatively little is known about their fine-scale movement patterns and how these affect the risks they face. There has been much debate on the conservation status and management needs for leopards with much extrapolation from limited data. In order to gather more information on leopard movements in Botswana’s Northern Tuli Game Reserve, seven leopards were collared between February 2005 and August 2006. This allowed key aspects that affect demography, and thus resilience to anthropogenic effects, to be investigated. Generally, home ranges were typical for breeding females in woodland savanna (32.9 ± 7.3 km²) with substantial overlap (average 26.0%). Core areas though were independent and extremely small (1.9 ± 2.2 km²). These were used primarily for young cub rearing, and were characterized by rugged terrain along riverbeds. This highly localized use places leopards at potential risk of snaring as snares tend to be concentrated along these landscape features. Furthermore, hunters can conceal blinds from which to shoot leopards more easily in these areas. Further risk to adult female survival came from excursions outside the reserve boundary during which livestock was predated. Three incidences of cannibalism by adult territorial males on adult females are also reported, suggesting significant intra-specific competition.
2

Home range dynamics of black bears in the Alleghany Mountains of western Virginia

Olfenbuttel, Colleen 21 October 2005 (has links)
The Cooperative Alleghany Bear Study (CABS) was initiated in 1994 to address concerns over the lack of biological and ecological data for black bear (Ursus americanus) populations in the Alleghany Mountains of western Virginia. I examined home range dynamics of bears during 1994-2002 on 2 study areas that were approximately 160 km apart. I analyzed my data with 3 home range programs (AMA, HRE, and ABODE) and determined the HRE was the least biased and produced the most biologically reasonable home range estimates. I used HRE to generate annual home ranges (fixed-kernel) for 90 bears over 160 bear years; I also generated seasonal home ranges using MCP. Annual and seasonal home ranges of male and female adult bears in the southern study area were larger than that of male and female adult bears in the northern study area, respectively; southern females and northern males had annual home ranges similar in size at the 95% and 75% fixed-kernel contours. In both study areas, most bears did not shift their range when transitioning from spring to summer (North: 63.0%; South: 57.0%) or from summer to fall (North: 67.0%; South: 65.0%), while most bears shifted their seasonal range between spring and fall (North: 67.0%; South: 52.0%). Most female bears in both study areas maintained the same spring and summer home range throughout the duration of the study, while 63% of northern females changed their fall home range and 55% of southern females maintained their fall home range. I found no differences in annual and seasonal home range size among years or among age classes for adult females, but tests for intra-year seasonal difference indicated that fall range was larger than spring and summer in 1997, when western Virginia experienced a poor mast crop. Females with and without COY had similar annual home ranges in either study area. In the north, seasonal home range size did not differ between females with and without COY, while in the south, breeding females (i.e. without COY) had larger spring ranges and smaller fall ranges than females with COY. In both study areas, females with COY had larger fall home ranges than during spring, while seasonal ranges of breeding females did not vary in size during the year. / Master of Science
3

An assessment of Quality Deer Management on a private hunt club in the Virginia Piedmont

Batts, Gregory K. 10 June 2008 (has links)
I examined the efficacy of Quality Deer Management (QDM) on Amelia Springs hunt club in Amelia County, Virginia, during 2003-2006. I examined home range dynamics of male white-tailed deer (Odocoileus virginianus), deer/hunter interactions, and aspects of population dynamics. I also developed a new rocket net method to capture deer using a remote video system that was more efficient than traditional methods. I monitored 20 deer; 50% died due to hunting and 15% to natural mortality. The emigration rate for juvenile males was 46%, dispersal distance averaged 6.4 km. I used Home Range Extension (HRE) in ArcView to generate annual home ranges (adaptive-kernel) for 16 male deer; I also generated annual and seasonal home ranges using MCP. Annual and seasonal home ranges (MCP) of adult males were larger than those of juveniles. Adult male annual home ranges averaged 2.5 km2 and juveniles 0.9 km2. Seasonal home ranges of adult males were 1.6 km2 and 1.3 km2 during non-hunting and hunting seasons respectively. Juvenile non-hunting and hunting season home ranges were 0.6 km2 and 0.8 km2 respectively. I detected no differences in day/night movements of male deer during the hunting season; however, deer appeared to avoid areas that were hunted based on hunter GPS locations and deer locations during the hunting season. Frequency of deer movement increased during October-November. Population estimates based on remote camera mark-recapture averaged 60 antlered males for the 3-year survey period. Using population reconstruction, the minimum buck:doe ratio was 1:1.8. Estimated density of antlered males was 4.1/km2, in Amelia County, and 5.0/km2 for Amelia Springs. Deer harvested on Amelia Springs, compared to deer harvested on other hunt clubs in Amelia County, were larger. Antler diameters averaged 32.6mm on Amelia Springs versus 26.9mm for other Amelia county hunt clubs, average age at harvest for 2+ males was higher on Amelia Springs (2.4) than other Amelia county hunt clubs (2.2), and dressed body weights averaged 11.2kg heavier (46.2 kg versus 35 kg) on Amelia Springs. QDM on Amelia Springs appears to be successful based on the results. While bigger bucks existed on Amelia Springs, hunters failed to encounter them. Hunters likely would increase buck sightings during the hunting season by becoming more mobile. Expectations of the size of animal (antlers) Amelia Springs can produce should be adjusted to reflect what is possible based on the habitat. The harvest program in place should be continued at the current level for continued success using QDM. / Master of Science
4

Landscape of Stress: Does Drought Prevail Over Anthropogenic Activity in Influencing Cortisol Levels and Fitness in the Pacific Fisher?

Kordosky, Jennifer R. 01 May 2019 (has links)
Fishers (Pekania pennanti) are a species of concern in the Sierra Nevada Mountains of California. Cortisol is a glucocorticoid hormone released to mobilize energy in response to stress and has been used as an indication of an individual’s physiological response to its environment. By collecting samples of fisher hair and measuring an individual’s cortisol, we examined the physiological stress response of the animals to human disturbances (housing density, road density, habitat type, and silvicultural treatements) and drought (tree mortality) in their home ranges. Using AICc model selection, we found that levels of tree mortality within a fisher’s home range significantly influenced cortisol levels. Various human disturbances had a smaller effect on cortisol levels. Furthermore, we examined the relationship between cortisol and fitness through the metrics of body condition, female kit counts, and survival. We found that females with low cortisol had significantly higher survival rates than females with medium and high cortisol. With the recent drought, bark beetle infestation and subsequent tree mortality being >80% in some areas of our study, cortisol levels could continue to increase, potentially leading to further decreased fitness within this fisher population. We also examined the difference in habitat selection between the core and entirety of the home ranges and found that fishers prefer late-successional forest in the core of their home ranges.
5

Temporal Variation in Space and Resource Use of Macaws in the Southeastern Peruvian Amazon

Adamek, Krista Anne 2011 May 1900 (has links)
Space use and resource use of three species of macaws (Ara ararauna, A. chloropterus, and A. macao) were studied for a period of three years in the southeastern Peruvian Amazon. Basic information on wild macaw populations is lacking due to the logistical and behavioral challenges of working with these species in dense rainforest. Population declines world-wide have been attributed significantly to a reduction in food and nesting resources due to habitat loss. This research aims to obtain baseline data on macaws in a region with relatively intact rainforest. Specific objectives were to (1) quantify space use, describe the spatial and temporal variation in movement patterns, explore habitat selection and spatial pattern of resources during the non-breeding season, and (2) identify key nesting and foraging species and determine whether there is seasonal variation in diet, and explore how resources may be related to movements and competition. Individuals from each species were radio-tagged and monitored from 2004 to 2008 by ground, platform, and aerial tracking. Seasonal ranges were estimated using MCP and KDE methods. Diversity and niche measurements and selection were calculated for dietary items, nesting substrate, and habitat. The relationship between palm habitat distribution and A. ararauna movements was explored using landscape analysis techniques. All species had similar home range sizes during the breeding season, ranging from a mean of 1,540 ha to 2,541 ha. Non-breeding ranges were significantly larger for A. ararauna (117,849 ha). Greater than 200 species of plants were consumed, yet seasonal preferences vary. The increase in dietary breadth and decrease in overlap during dry season is unlikely related to food scarcity or competition. Key nesting and dietary species include Mauritia flexuosa, Dipterix micrantha, and Bertholletia excelsa. Palm habitat is a key resource for Ara ararauna and associated with long-distance movements. This research addresses a critical gap in our knowledge regarding macaw movements and resource use in Amazonian rainforest. Despite their mobility, their low fecundity and specialized nesting requirements can impact reproductive success and population growth if habitat loss continues on its current trajectory.
6

Gradients of predation risk affect distribution and migration of a large herbivore

Grigg, Jamin Lyle. January 2007 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Robert A. Garrott. Includes bibliographical references (leaves 57-63).
7

Nesting Ecology, Survival, and Home Range of Wild Turkeys in an Agricultural Landscape

Delahunt, Kenneth Scott 01 May 2011 (has links)
Most research on Eastern wild turkeys (Meleagris gallopavo silvestris) has occurred in extensively forested habitats atypical of midwestern landscapes. I studied the ecology of female wild turkeys in a portion of southern Illinois consisting of an agricultural matrix interspersed with forest, and grassland cover types. I quantified causes of hen and nest mortality, nesting habitat variables, nesting rates, nest success, clutch and brood sizes, and incubation length. I also examined daily nest and weekly hen survival rates, and hen and brood home ranges and habitat selection. Sixty-four hens were radiomarked during 2008-10. Predation was the primary cause of nest mortality (80.5%) and hen mortality (100.0%). Coyotes (Canis latrans) were responsible for 40.3% of nest mortalities and 42.8% of hen mortalities, whereas bobcats (Lynx rufus) caused 42.8% of hen mortalities. Weekly survival rates were 98.7 and 98.6% for adult and juvenile hens, respectively. Seasonal survival rates for adult hens varied from 68.7% during breeding to 88.9% during winter. Most hens (98.5%) made a first nest attempt, 75.6% of hens attempted a second nest, and 8.0% of hens attempted a third nest. Mean clutch size was 12.4 ± 0.4 (SE throughout) during the first nesting attempt and 9.6 ± 0.6 during the second nesting attempt. The mean incubation length of successful nests was 31.1 ± 0.8 days. Mean nest success was 19.8%, producing 11.3 ± 3.3 poults/per
8

Survival, Home Range and Spatial Relationships of Virginia's Exploited Black Bear Population

Higgins, Jennifer C. 02 September 1997 (has links)
Eighty-three (21M, 62F) of 194 black bears captured during 1994-1996 were equipped with radio collars. Annual survival rates estimated with Kaplain-Meier staggered entry approach for radio collared adult females, adult males, subadult females, and subadult males were 95.3, 100.0, 90.4 and 50.0% respectively. Hunting, handling, vehicle collisions, and natural causes accounted for 81.0, 11.1, 3.2, and 1.6% of mortality. Twenty, 9.8, and 70.6 % of bears harvested were harvested in the deer firearm season, the deer archery season, and the bear firearm season, respectively. Twenty-three cubs were equipped with expandable radio collars (11M,10F) or transmitters implanted subcutaneously (2M,0F) in 1995-1996. Six cubs (4M, 2F) died, 6 (3M,3F) survived their first year, and the status of 11 cubs (6M, 5F) was unknown. Survival rates (date marked until 4 December) estimated with Kaplain-Meier and Heisey-Fuller were 64.3 and 64.7% respectively. Interval survival rates were 71% (15 March to 31 May), 100% (1 June to 31 July), 92% (1 August to 31 August), and 100% (1 September to 4 December). Intraspecific aggression (33.3%), starvation (16.7%), unknown causes (16.7%) and predation (16.7%) were the causes of mortality. Total home range size for males and adult, subadult, and transitional age females were 7.2, 5.5, 5.6 and 7.2 km2 (95% MCP) and 11.2, 6.8, 9.0, and 10.0 km2 (95% normal kernel). Females with cubs had larger fall ranges than spring and summer ranges. Seasonal ranges of solitary females did not differ when estimated with MCP. Bears exhibited home range overlap among and within sex classes. / Master of Science
9

Differential Behavior of Coyotes with Regard to Home Range Limits

Harris, Charles E. 01 May 1983 (has links)
This study was conducted to examine coyote behavioral responses to novel stimuli in familiar and unfamiliar environments and the implications of this behavior with regard to specific coyote management and research techniques. A series of pen studies with captive coyotes was undertaken at the U.S. Fish and Wildlife Service's Predator Ecology and Behavior Project research site, Logan, Utah, to observe the range and type of behaviors coyotes showed towards small novel objects and standard scent stations in familiar and unfamiliar 1-ha enclosures. The initial response to these novel stimuli in familiar environments was one of neophobia and caution, whereas in the unfamiliar environment these same stimuli were readily approached and investigated. Field studies were undertaken at the Idaho National Engineering Laboratory and Freer, Texas, to examine coyote visitation to scent stations inside, peripheral to, and outside their defined home ranges. Radio-collared coyotes were monitored to determine home range use and movement patterns, with relocations plotted on computer graphic maps and gridded base maps. Modified scent-station survey lines were run and visitations by marked coyotes plotted with respect to home range zone. Marked coyotes visited a greater percentage of scent stations peripheral to and outside their home ranges than inside. The socio-spatial distribution of coyotes, home range size, and percentage of road comprising home range zones influenced differential scent-station visitation rates. The importance of understanding the influences of animal behavior on wildlife management and research techniques is discussed.
10

Feral hogs in central Mississippi:home range, habitat use, and survival

Hayes, Robert Clay 05 May 2007 (has links)
I examined home range, habitat use, and survival of 29 feral hogs in central Mississippi using radio telemetry. During the dry season (1 April - 31 October 2005), densely-vegetated habitats were very important in home range placement (2nd-order selection) with selection favoring seasonallylooded old fields, followed by old fields and managed openings. During the wet season (1 November 2005 - 31 March 2006), old fields were still preferred followed by agricultural fields, but flooded old fields were not preferred. For habitat selection within the home range (3rd-order selection), hogs preferred old fields and managed openings during the dry season. All habitats were used randomly within home ranges during the wet season. Dry and wet season survival rates were 80.8% and 41.4%, respectively. Hunting was the major cause of mortality (80 ? 100%). Seasonal differences in habitat selection may have been caused by flooding of preferred habitats, food availability and hunting.

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