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Winter habitat selection, winter diet, and seasonal distribution mapping of moose (Alces alces shirasi) in southeastern WyomingBaigas, Phillip E. January 2008 (has links)
Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on Dec. 4, 2009). Includes bibliographical references (p. 154-163).
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HABITAT SELECTION OF REINTRODUCED BISON IN NORTHERN ILLINOISBrockman, Julia C. 01 August 2017 (has links)
In one of the first reintroductions of a semi-wild population of bison (Bison bison) east of the Mississippi River, The Nature Conservancy reintroduced bison to the Nachusa Grasslands in northern Illinois in October 2014. Given the novelty of such efforts, questions remain regarding how human activity and prairie management affect bison habitat selection. My objective was to quantify bison habitat selection during 2014-16 to address literature gaps while investigating seasonal and annual changes. In October 2014, The Nature Conservancy collared 7 female bison with Lotek Iridium TrackM 3D and 4D collars programmed to take hourly locations. I randomly selected 1 bison location each hour to represent herd location and divided the resulting locations by season. Using resource selection functions, I compared the influence of land cover type, fire management, and concentrated human activity on habitat selection across seasons and at 2 scales: patch and enclosure. Land cover was consistently the best-fit model across seasons and scales with the exception of Winter 2016 at the enclosure scale. Bison strongly selected for partial restorations but showed no strong seasonal land cover selection trends. Bison selected for recently-burned prairie with the exception of Summer 2015 at the enclosure scale. At the patch scale, bison selected for areas closer to disturbed areas but did not show a strong trend at the enclosure scale. With a better understanding of how bison grazing is influenced by restoration management, wildlife managers can make better-informed decisions regarding bison restoration and public use.
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Ecological features of moose Alces alces andersoni winter habitat in the boreal white and black spruce zone of northeastern British ColumbiaSilver, Roderick Sterling January 1976 (has links)
A study of the dispersion patterns of moose in winter habitats was conducted from June 1972 to May 1974 in a wildlife reserve in northeastern British Columbia. Major factors affecting the patterns were examined in an attempt to determine their relative importance.
Data from eight representative vegetation plots indicated productive browse in deciduous forests and open habitats. In coniferous forest there was very little shrub development.
Moose were well adapted to low winter temperatures which often followed warm winter temperatures associated with Chinook winds. Snow cover rarely exceeded 76 cm. Canopies of mature coniferous forest profoundly influenced the depth of snow on the ground, but, because the snow depth in open areas was not restrictive, moose did not extensively use coniferous forest. Willow, aspen and bog birch were the most important forage species. Rumen analyses and trailing methods supported these observations. Instances of moose cratering (pawing) and debarking were observed.
Winter forages (probably a limited sample) were very low in crude protein.
Open shrubland, agricultural land, and deciduous forest were preferred winter habitat. Several variables, quantified during ground and aerial observations, were used in a model to predict moose dispersion, but the model was applied with limited success.
Future management of habitat for moose should include logging and prescribed burning to enhance the forage resource. The purchase of alienated lands to ensure control of the land base is also recommended. / Land and Food Systems, Faculty of / Graduate
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Winter habitat selection and use of clearcuts by elk in the White River drainage of southeastern British ColumbiaChurchill, Brian Phillip January 1982 (has links)
This study of elk winter habitat selection was conducted from June 1975 to May 1977. Surveys were conducted from November to April to observe elk use of habitat, patterns of use within clearcuts, and elk reaction to human activities and vehicle traffic. Programmes of habitat mapping, vegetation description and pellet group counts were conducted during the rest of the study period.
The two winters of the study were mild. Snow depths never exceeded 45 cm, the depth hypothesized to initiate elk movement to areas of lower snowdepth. During these mild snow conditions elk selected clearcuts for feeding but utilized forested habitats for resting and escape cover. Subsequent studies in the same area (McLellan 1978) showed contrasting avoidance of clearcuts for two months during deep snow conditions where snowdepths exceeded 50 cm.
Within clearcuts elk were observed to select moderate slopes further than 200 m from active roads for feeding and resting. Feeding activities within clearcuts showed selection for ridges, grass/forb vegetation and burned areas. Elk showed varying responses to slash accumulations during feeding activity. Elk selected the largest clearcut site and no preference for areas near edge of clearcuts was shown. Elk showed a strong
avoidance reaction to human activity and vehicle traffic, fleeing to forest cover when disturbed. Recommendations for forest management are included. / Forestry, Faculty of / Graduate
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The role of fire, microclimate, and vegetation in lesser prairie-chicken habitat selectionLautenbach, Jonathan David January 1900 (has links)
Master of Science / Division of Biology / David A. Haukos / The lesser prairie-chicken is a prairie grouse native to the southwestern Great Plains that has experienced significant population and habitat declines since European settlement. Ongoing declines prompted the U.S. Fish and Wildlife Service to list lesser prairie-chickens as threatened under the Endangered Species Act in spring of 2014. In fall of 2015, the listing was vacated on procedural grounds and the lesser prairie-chicken was removed from listing in summer 2016. Despite the legislative change, considerable conservation efforts emerged with the initial listing and have continued following the removal of the species from the threatened and endangered species list. Understanding how lesser prairie-chickens use landscapes and how management actions can influence their space use is important for long-term strategies to meet conservation goals. I modeled lesser prairie-chicken habitat selection relative to landscape mosaics of vegetation patches generated through patch-burn grazing, microclimate, and vegetation characteristics across their range. I captured, attached GPS satellite or VHF radio transmitters to, tracked, and measured vegetation characteristics used by and available to female lesser prairie-chickens across the northern portion of their range in Kansas and Colorado. Female lesser prairie-chickens use all patch types created in a patch-burn grazing mosaic, with female selecting greater time-since-fire patches (>2-years post-fire) for nesting, 2-year post-fire patches during the spring lekking season, 1- and 2-year post-fire patches during the summer brooding period, and 1-year post-fire units during the nonbreeding season. Available vegetation structure and composition in selected patches during each life-cycle stage was similar to the needs of female lesser prairie-chickens during that life-cycle stage. To assess their selected microclimate conditions, I deployed Maxim Integrated Semiconductor data loggers (iButtons) at female flush locations and across a landscape inhabited by lesser prairie-chickens. Females selected locations that minimized thermal stress at microsite, patch, and landscape scales during peak midday temperatures during summer. Females selected midday locations based on vegetation characteristics; where selected sites had >60% forb cover and <25% grass cover, or >75% grass cover and <10% forb cover. In addition, females selected sites with greater visual obstruction. I measured vegetation composition and structure at use and available sites at four study areas located along the precipitation gradient characterizing the full extent of the lesser prairie-chicken range. Vegetation structure use by females varied in relation to long-term precipitation patterns. Females used sites with lower visual obstruction than available during the fall and spring. However, they used vegetation composition that was similar to available within each study area. Overall, my findings indicate that lesser prairie-chickens require structural and compositional heterogeneity to support a suite of habitat needs throughout the year. Therefore, management should focus on providing structural and compositional heterogeneity across landscapes. Greater heterogeneity in vegetation conditions can be achieved through management practices that allow domestic grazers to select grazing locations, such as patch-burn grazing or increased pasture area.
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Metapopulation Dynamics and Multi-Scale Habitat Selection of a Montane Forest SongbirdFrey, Sarah 24 June 2008 (has links)
Variations in species occurrence and distribution across the landscape over time provide fundamental information concerning population dynamics. How this relates to habitat characteristics at multiple scales can elucidate the process of habitat selection. I evaluated these processes for a montane fir (Abies) forest specialist, Bicknell’s Thrush (Catharus bicknelli) in Vermont. This species is threatened by a suite of anthropogenic disturbances on its breeding grounds and quantifying the effects of environmental change at the population level for this songbird has not been addressed. The naturally fragmented breeding habitat of varying size, quality, and connectivity warranted a metapopulation approach and a robust occupancy analysis. Detection/non-detection data was collected for Bicknell’s Thrush across 88 sites during the breeding seasons in 2006 and 2007. Local habitat characteristics were measured for each site and landscape-level features were calculated using a predictive habitat model. The six local habitat variables were combined using a principal component analysis. Principal component 1 (PC1) described a gradient of increasing coniferous shrub density and proportion of coniferous dominated forest with decreasing canopy height. The landscape covariate was calculated by dividing patch size by patch isolation creating a continuum of small, isolated patches to large, less isolated patches. Thus each site was characterized by a single local habitat (PC1) and landscape metric. From these data, 67 models considering all combinations of landscape and local habitat scores (univariate, additive and interaction) were evaluated for individual estimates of the following parameters: (1) probability of detection, (2) probability of initial site occupancy, (3) probability of site colonization, and (4) probability of local site extinction. AIC model selection techniques were used to rank the models, which represented ecologically plausible hypotheses that compared the strength of local habitat characteristics to large-scale landscape features. Models within 4 AICc points of the top model were considered plausible. The top eight models were all plausible. Landscape characteristics alone were not significant in driving population dynamics. The relative importance of landscape + local habitat was highest for both probability of initial occupancy and local site extinction. Probability of occupancy increased and extinction decreased with the combination of increased patch size and decreased patch isolation (landscape) and increased coniferous shrub density, proportion of coniferous dominated forest and decreased canopy height (local habitat). Probability of site colonization was driven mainly by local habitat features and increased with increasing habitat quality. These results indicate a complex system with intricate links between landscape and local scales. Preserving large tracts of habitat may not be sufficient in assuring future species persistence, but could minimize local extinction risk. Careful consideration should be given to local habitat features within habitat fragments, particularly to maintain adequate colonization rates. Because important features from both scales are correlated, in intact montane forest patches, landscape-scale attributes alone may serve as a surrogate for identifying quality breeding habitat, assuming processes of natural disturbance can be maintained.
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Natal dispersal, habitat selection and mortality of North Island Brown Kiwi (Apteryx mantelli) at the Moehau Kiwi Sanctuary, CoromandelForbes, Yuri January 2009 (has links)
The Moehau Kiwi Sanctuary is one of five sanctuaries established in 2000 and managed by the Department of Conservation. The objective of the sanctuaries is to protect the most endangered kiwi taxa, and increase kiwi survivorship. Operation Nest Egg (ONE) is a programme utilised by the Moehau Kiwi Sanctuary for artificially incubating abandoned Kiwi eggs and captive rearing chicks until they begin to show a gain in weight. ONE chicks were then released back onto Moehau or adjacent protected areas. Kiwi populations are declining on the mainland at an average of about 3% per year in areas where predators of kiwi are not controlled. The main cause for this decline is chick mortality due to predation by stoats (Mustela erminea). During natal dispersal kiwi are known to disperse significant distances of between 5–20 km, and this has influenced the size of management areas needed for the protection of kiwi (10,000 hectares). The type of forest-cover is an important element in determining where management areas are located, as kiwi has preferences for certain forest types over others. This study conducted at Moehau, Coromandel, on the North Island Brown Kiwi advances our knowledge of kiwi by examining differences in rates and distances of dispersal among chicks, sub-adults, non-territorial and territorial adults, as well as between genders. This study investigates kiwi selective use of roost site types, ground-cover types, forest types and physiographical features. Addressed in this study are differences in dispersal, habitat selection and mortality among age-classes and between genders over the months of the year, and across elevations. Comparisons between ONE and wild-reared kiwi dispersal and mortality are included. Data were collected between 2001 and 2008 from observations of kiwi located during daytime hours. The data recorded included the grid reference, elevation, ground-cover type, forest type, physiography, and the type of roost site. The sample size for this study was significantly larger than for any previous studies thus enabling a greater confidence in estimated dispersal rates and dispersal distances, habitat selection and factors relating to mortality. All wild-reared kiwi displayed dispersal and were not philopatric to their natal area. Dispersal distances were found to be further than previously estimated, with the net distance of natal dispersal differing among age-classes, from an average of 834m (SE +/- 131) for kiwi chicks to 7,553m (SE = +/- 1167) for non-territorial adults. Female sub-adult kiwi dispersed further (7,215m) than male sub-adult kiwi (4,226m) (p = 0.04). The time taken to travel one km during natal dispersal ranged from an average of 131days/km (SE = +/- 9) for chicks to 89 days/km (SE = +/- 13) for sub-adults. Habitat selection has been observed in other studies on kiwi but not specifically for Coromandel North Island Brown Kiwi, and selection for ground-cover types by kiwi when roosting on the surface has never been previously studied. Roost site selection of kiwi differed among age-classes (p <0.001), between gender (p <0.001), and across elevations (p <0.001). Female kiwi were found more often in surface roosts (64%) than hole roosts (32%), and male kiwi were found at similar frequencies in holes (46%) and on the surface (47%). Sub-adults used holes to a greater extent as elevation increased, and selected for sub-alpine forest over broadleaf forest (p <0.001). This study is the first to recognise that selection of ground-cover types by kiwi differs among age-classes (p <0.001). Kiwi chicks were more often found on the surface under dead fern fronds and debris (39%) than other ground-cover types. The mortality rate was highest in chicks (33%), with predation responsible for 60% of these deaths; conservation management techniques were responsible for a further 20% of deaths; the remaining 20% of deaths were due to natural or unknown causes. Summer (December-February) was the season in which 81% of kiwi chick deaths occurred. The high proportion of deaths from monitoring techniques and the use of radio-transmitters (22%) indicates improvements need to be made to current management practices. ONE chicks were found to disperse shorter distances and had a greater mortality rate than wild-reared chicks. Therefore, recommendations are made for changes to ONE management practices. Further recommendations are made for the enhancement of kiwi habitat that could reduce kiwi mortality, and for increasing the habitat available to kiwi, thereby potentially increasing population sizes and/or densities.
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Habitat selection, condition, and survival of Shiras moose in northwest WyomingBecker, Scott. January 2008 (has links)
Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on Nov. 19, 2009). Includes bibliographical references.
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Distribution and reproduction of dung beetles in a varying environment : implications for conservation of semi-natural grasslands /Vessby, Karolina. January 2001 (has links)
Thesis (Ph. D.)--Swedish University of Agricultural Sciences, 2001. / Thesis statement in Swedish and English abstract inserted. Includes bibliographical references.
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Trailblazers in the Forest: Response of Endangered Mt. Graham Red Squirrels to Severe Insect InfestationZugmeyer, Claire Ann January 2007 (has links)
I examined habitat selection of middens within insect-damaged forest and compared home range and survival for Mt. Graham red squirrels (Tamiasciurus hudsonicus grahamensis) in insect-damaged and healthy forest. Squirrels used habitat in areas with < 69% tree mortality. Basal area, canopy cover, and log volume were greater at middens than random locations. Within midden sites, only greater basal area of live trees distinguished occupied sites from unoccupied sites. Surface temperature at occupied middens tended to be cooler than unoccupied middens. Squirrels living in insect-damaged forest had larger home ranges than in healthy forest. Squirrel body mass and reproductive condition did not differ between forest types, suggesting that insectdamaged forest provided adequate resources. However, squirrels inhabiting insectdamaged forest experienced lower survivorship and 50% fewer potential reproductive events than squirrels in healthy forest, implicating presence of an ecological trap. Preservation of remaining healthy forest is a priority for management of this endangered species.
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