• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 4
  • 4
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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

Wildlife ecotourism elicits spatial and temporal shifts in grizzly bear activity in Kitasoo Xai’xais Territory on the Central Coast of British Columbia

Short, Monica 03 October 2022 (has links)
Ecotourism offers a non-consumptive form of economic activity globally. Human activity, however, might negatively affect the ecology of areas and their biota, likely varying with type and intensity of ecotourism. Wildlife, for example, might perceive ecotourists as predators, and adjust behaviour accordingly (i.e., human avoidance). Alternatively, wildlife might actually seek human activity if it protects them from greater risks (Human Shield Hypothesis). The Anthropause, a period of decreased human activity due to COVID-19, provided unparalleled opportunity to examine wildlife behaviour when perceived risks from humans were removed. In partnership with the Kitasoo Xai’xais First Nation (KX), we assessed if and how ecotourism, in the form of bear-viewing, might influence spatial and temporal activity of grizzly bears. We deployed remote cameras in the Khutze watershed in 2020 in the absence of human use. To provide increased inference when tourism resumed in 2021, KX implemented alternating spatial closure experiments within the watershed. Additionally, in 2021 we implemented a tourist group size experiment in a second watershed, Green River. In Khutze, we found that a closure of 25 days was required for bear detection rate to return to the 2020 (non-ecotourism) level. We did not observe an influence of the alternating within-watershed north-south closures on activity. The data also revealed complex relationships among bear detections, ecotourism activity, and salmon availability, varying by age and sex of bears. Specifically, we found a human shield effect for females with young when salmon levels were moderate to high, but this effect diminished in times of low salmon. An activity pattern analysis in Khutze did not show an effect of ecotourism. In Green, where inference was likely constrained by our short-term experiment, we found a positive influence of the number of days since people were present on detection rate. We additionally found temporal avoidance of within 100m of the viewing site on days when people were present. These patterns from both watersheds show the complex ways in which wildlife can respond to even seemingly benign human presence. Inference from this research has application to wildlife, land, and ecotour management by the KX, who are reasserting authority in governance. More broadly, this study contributes to literature on the dynamic landscape of fear induced by spatiotemporal variation in human activity. / Graduate / 2023-09-09
2

Habitat use and den site selection of mink (Mustela vison) along the Hudson River and its tributaries in east-central New York.

Haan, Damon 01 August 2011 (has links)
Mink (Mustela vison) are an important species because they occur at a high trophic level, they are considered a potential indicator species for environmental contaminants, and they are a popular target species among fur trappers. Despite the importance of mink, their ecology in North America is not well understood. I sampled 59 of 60 Hudson River tributaries with 2 scent stations randomly established along each tributary for 2 10-day monitoring periods to evaluate presence/absence of mink via remote camera photographs and tracks. When sampling was completed, I quantified microhabitat characteristics at 84 randomly selected scent stations. Statistical tests for microhabitat did not indicate a difference among variables selected for analysis between scent stations where mink visits were detected and those where mink visits were not detected. I also analyzed all scent stations for macrohabitat characteristics related to human disturbance, using 150 m circular buffers in ArcGIS 9.2. Although the percent cover of human disturbance was 7.0% greater at scent stations where mink were not detected, the difference was not significant and may therefore indicate that mink may have a tolerance for moderate human disturbances. I also evaluated the performances of 2 types of remote cameras (Moultrie Game Cameras: MGC I–40 and MGC 200) in detecting mink visits at scent stations as well as comparing remote camera detections of mink visits with observations of tracks. The MGC I–40 cameras detected a significantly greater number of mink visits (n = 50) compared to the MGC 200 cameras (n = 3). Detection of mink at scent stations was also significantly greater using the remote cameras compared with observations of mink tracks. Mink were also live–trapped and implanted with subcutaneous radiotransmitters. There were 13 mink captures (0.31 mink/100 trap–nights) with radiotransmitters being implanted in 12 (11 males and 1 female) mink. Overall 166 den sites were located with a mean of 15.9 den sites/mink. Microhabitat analysis of 33 used den sites and 33 unused potentially available den sites (UPADs) indicated that shoreline cover was significantly greater at used den sites. Macrohabitat analysis using 150 m circular buffers surrounding 76 used den sites and 76 unused potentially available sites (UPASs) indicated that human disturbance was 3.3% greater at the UPASs than at used den sites, but this difference was not significant. This may further suggest that mink may have a tolerance for moderate human disturbances. Den site structures most often used by mink included brushpiles or logjams (21.1%) and bank burrows (17.5%). The use of den site structures appeared to be largely based on shoreline cover and availability. The mean linear home range of male mink was 6.6 km (SE = 0.6, range 3.2 – 8.4 km), which was similar to the female's home range of 6.5 km. Ten mink home ranges encompassed portions of both the Hudson River and its tributaries accounting for a mean of 2.8 and 4.4 km, respectively. Mean daily movement distances of mink along shorelines was 659 m (SE = 42, range 0 – 3,087 m) and was significantly greater along tributaries than along the Hudson River.
3

Bobcat Abundance and Habitat Selection on the Utah Test and Training Range

Muncey, Kyle David 01 December 2018 (has links)
Remote cameras have become a popular tool for monitoring wildlife. We used remote cameras to estimate bobcat (Lynx rufus) population abundance on the Utah Test and Training Range during two sample periods between 2015 and 2017. We used two statistical methods, closed capture mark-recapture (CMR) and mark-resight Poisson log-normal (PNE), to estimate bobcat abundance within the study area. We used the maximum mean distance moved method (MMDM) to calculate the effective sample area for estimating density. Additionally, we captured bobcats and estimated home range using minimum convex polygon (MCP) and kernel density estimation (KDE) methods. Bobcat abundance on the UTTR was 35-48 in 2017 and density was 11.95 bobcats/100 km2 using CMR and 16.69 bobcats/100 km2 using PNE. The North Range of the study area experienced a decline of 36-44 percent in density between sample periods. Density declines could be explained by natural predator prey cycles, by habituation to attractants or by an increase in home range area. We recommend that bobcat abundance and density be estimated regularly to establish population trends.To improve the management of bobcats on the Utah Test and Training Range (UTTR), we investigated bobcat (Lynx rufus) habitat use. We determined habitat use points by capturing bobcats in remote camera images. Use and random points were intersected with remotely sensed data in a geographic information system. Habitat variables were evaluated at the capture point scale and home range scale. Home range size was calculated using the mean maximum distance moved method. Scales and habitat variables were compared within generalized linear mixed-effects models. Our top model (AICc weight = 1) included a measure of terrain ruggedness, mean aspect, and land cover variables related to prey availability and human avoidance.
4

Optimizing Monitoring Efforts of Kit Fox (<em>Vulpes macrotis</em>) in Utah

Richards, Kelsey Alina 01 November 2017 (has links)
The kit fox (Vulpes macrotis) is a species of conservation concern in western North America. Recent methods for monitoring populations of kit fox include using lures and remote cameras in an occupancy-modeling framework and habitat modeling to predict areas of occupancy. In chapter one, we tested the optimal lure and movement procedure for scent stations to maximize visits and detection of foxes, thereby improving estimates of occupancy. Between May 2015 and October 2016, we placed remote cameras at 522 random locations throughout nine study areas in the Colorado Plateau, Great Basin Desert, and Mojave Desert. Each location was randomly assigned one of three methods (Scented Predator Survey Disks, cotton swabs, or hollowed golf ball) to broadcast one of three lure types (Red and Gray Fox liquid lure, Willey liquid lure, and fatty acid lure). After seven nights, half of all stations were moved 100 meters within the same sample grid cell, while the others remained in the same location. Stations were then monitored for an additional week. We used Program MARK and AIC model selection to identify optimal lure types and broadcast methods and to estimate rates of occupancy. Detection of kit foxes differed by method of scent deployment; cotton swabs were associated with the highest rates of visitation. Detection of kit foxes did not differ by lure type. Relocating the scent station after one week did not influence detection probability. We suggest that the use of cotton swabs maximizes detection, and therefore, the precision of estimates of occupancy. For chapter two, we used resource selection functions to identify variables that best discriminated between locations where kit fox were detected and random locations. We then produced a habitat map that predicted the relative probability of kit foxes occurring across seven study areas throughout the state of Utah. We placed remote cameras at 458 randomly selected locations throughout the study areas in the Colorado Plateau, Great Basin Desert, and Mojave Desert. We detected kit foxes at 157 "use" points from these cameras between May 2015 and October 2016. We then compared the attributes of these "use" points to 14,742 available, randomly selected points located within the study areas using variables derived from a Geographic Information System (GIS). We used model selection and minimization of AIC values to determine key habitat characteristics that differentiated use and random locations. We identified slope, elevation, and soil type as significant variables (P < 0.05) in habitat selection of kit foxes. Kit foxes selected areas that were 1) less steep, 2) lower in elevation, and 3) classified as having silty soils. The identification of these specific variables from our modeling effort was generally consistent with kit fox ecology. Our study produced a habitat model that can serve as a foundation for future monitoring efforts of kit foxes in potential habitat across Utah.

Page generated in 0.062 seconds