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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

Occurrence of Bornean Mammals in Two Commercial Forest Reserves and Characteristics that Influence their Detectability

Wong, Seth Timothy 08 December 2017 (has links)
The Southeast Asian island of Borneo boasts an incredible diversity of terrestrial mammals which is threatened by habitat loss. Understanding the abundance and distribution of these species is essential for conservation and management. We assessed the occurrence of terrestrial mammals within two commercial forest reserves in Sabah, Malaysian Borneo. In particular, we investigated the habitat associations of the Sunda stink-badger, whose patchy distribution is not well understood. To improve detection probability and precision of model parameters, we deployed 2 camera-traps at sample stations. Our results showed that Sunda stink-badgers are likely dietary and habitat generalists, that may benefit from forest disturbance. Additionally, we found that unguligrade species were associated with high detection probability when data from one camera trap was considered and inclusion of a second camera further increased the detectability of ungulates compared to all other species. We suggest that future studies consider physical characteristics of focal species to maximize effectiveness of camera effort and ensure that data collection is efficient and meets project needs.
2

Using Camera-Traps to Evaluate the Relative Abundance of Predators and Prey on the Western Slope of the Panama Canal

Ashmore, Jordan Rivers 01 December 2009 (has links)
Little research has been conducted in the Republic of Panama concerning mammalian predator and prey populations. New Technologies such as remote camera-traps, allow researcher to efficiently monitor elusive wildlife species within dense tropical vegetation. The general goal of this study was to establish concrete evidence of the felid population in EcoParque Panama-a newly designated protected area adjacent to Panama City. The specific objective of the study was to estimate the relative abundance of predators and prey species in order to determine the feasibility of releasing more felids into the area that were to be removed from the Panama Canal Expansion Zone. Camera-traps were purposefully located in likely felid habitat and data were collected for approximately 5 months. Photographs were analyzed according to species and location captured, and abundances were established. Using SPSS and Statistix statistical software, tests for association between likely habitat for felids and time activity periods for prey species were conducted. EcoParque was found to have a robust prey population with relatively few predators. Felid predators present include the ocelot (Leopardus pardalis) and jaguarundi (Felis yaguarondi). Results suggest that felid carrying capacity has not been reached and additional individuals could be released into the area. This preliminary study lays the ground work for further research in EcoParque as well as the rest of Panama concerning predator and prey species relationships.
3

Ecological study of the ocelote (Leopardus pardalis) using the camera trap technique, in Las Piedras Region, Madre de Dios-Peru / Estudio ecológico del ocelote (Leopardus pardalis) utilizando el método de cámaras trampa en el distrito de Las Piedras, Madre de Dios - Perú

Castagnino Vera, Romina 10 April 2018 (has links)
The study focuses in the ecology and conservation of the ocelot (Leopardus pardalis) in the conservation and tourism concession owned by the ARCC. The study site is 11 000 hectares and it is located in the Las Piedras Region, north of Tambopata province, Madre de Dios. Camera traps were used to monitor the ocelot population during a 7-month period (from August 2012 to February 2013), divided in 9 rounds were 73 cameras were installed. The camera traps found 8 independent ocelots, from which only 3 (A1, A3 and A6) were recaptured in more than one occasion. The study did a capture-recapture analysis. The distance traveled by the ocelots from a capture to a recapture site was used to estimate the effective sampled area using the Mean Maximum Distance Moved - MMDM and Half MMDM. The methods yielded a density of 70 individuals/100km2 and 180 individuals/100km2, with full MMDM and Half MMDM, respectively. The study also analyzed the camera trap capture probability with PRESENCE software. Using a closed CR analysis followed by a model of constant capture probability, it yielded a capture probability rate of 0,3 (SE 0,0567). Finally, the ocelot’s habitat preference was also studied using a combination of satellite imagery and GIS software. It was found that these animals frequently use transects aimed for tourists, prefer sites near water and that they avoid bamboo forests. / Este estudio trata sobre la ecología y conservación del ocelote (Leopardus pardalis), en la concesión de conservación y ecoturismo del albergue Amazon Research and Conservation Center - ARCC. El área de estudio, de 11 000 hectáreas, se encuentra ubicada en el distrito de Las Piedras, norte de la provincia de Tambopata, departamento de Madre de Dios, Perú. Se utilizaron cámaras trampa para monitorear la población del felino en un período de siete meses (de agosto de 2012 a febrero de 2013), dividido en nueve rondas donde se instalaron 73 cámaras en total. Fueron ocho ocelotes independientes los identificados, de los cuales solo tres (A1, A3 y A6) fueron recapturados visualmente en más de una ocasión. Se realizó un análisis de captura-recaptura. Las distancias recorridas por los ocelotes entre captura y recaptura se utilizaron para estimar el área efectiva de muestreo usando el método del Promedio de la Máxima Distancia Recorrida - MMDM y Mitad del MMDM. Los métodos dieron como resultado una densidad poblacional de 700 ocelotes/100 km2 y 180 ocelotes/100 km2 con MMDM y Mitad del MMDM, respectivamente. Por otro lado, se analizó la probabilidad de captura de las cámaras trampa con el software PRESENCE. Utilizando un análisis poblacional cerrado y un modelo constante, se halló una detección por ronda de 0,3 (SE 0,0567). Finalmente, también se evaluó la preferencia de hábitat de los ocelotes a través de imágenes satélite. Se halló que la mayoría de los felinos usan transectos turísticos, que prefieren las llanuras aluviales cercanas a las riberas de los ríos y cochas, y que evitan los pantanos.
4

Seasonal Distributions of Wildlife Inhabiting the Madrean Archipelago

Thompson, Kyle, Thompson, Kyle January 2016 (has links)
Species distributions reflect the suite of resources and range of environmental conditions required by a species. Distributions of many species change seasonally, however, in response to changes in resource availability and environmental conditions, many of which are projected to shift in response to climate change. We sought to identify environmental and anthropogenic factors associated with seasonal changes in the distribution of vertebrates that inhabit the Madrean Archipelago in southern Arizona, which is important for identifying mechanisms through which climate change may affect these species. From July 2012 to February 2015 (966 days), we used remote cameras to survey 200 sites across 16 mountain ranges for a total of 69,434 trap days and used dynamic occupancy models to determine how landscape features, vegetation composition, and anthropogenic factors influenced the distributions and seasonal rates of local colonization and extinction of 13 vertebrates. For these 13 species, we recorded 37,888 detections, with gray foxes, skunks, and squirrels detected most frequently. Bobcats, cottontails, gray foxes, skunks, squirrels, javelina, puma, and coatimundis were all detected across the entire range of elevations surveyed, from 935 to 2395 m. Black bears and wild turkeys were never detected below 1270 m, Sonoran opossums never detected above 1980 m, and coyotes and ringtails never detected above 2020 m. Composition and structure of vegetation in the understory, midstory, and overstory influenced initial occupancy of several species, including skunks, coatimundis, Sonoran opossums, and cottontails. Season, either directly or as an interaction with the estimated amount of solar radiation reaching a site, influenced local extinction rates of all 13 target species and local colonization rates of 9 of 13 species. Elevation influenced local colonization rates of black bears and coatimundis positively, and coyotes, Sonoran opossums, and cottontails negatively, and local extinction rates of skunks negatively and coyotes and black bears positively. These patterns indicate that the distributions of many species in this region change seasonally, likely as a mechanism to meet dietary, behavioral, or physiological needs in response to shifts in environmental conditions and resource availability. Therefore, species that depend on seasonal resources may be at higher risk of distributional shifts or range contractions if the distribution and phenology of these resources change in response to changes in climate.
5

Contemporary land-use change structures carnivore communities in remaining tallgrass prairie

Wait, Kyle January 1900 (has links)
Master of Science / Department of Horticulture and Natural Resources / Adam A. Ahlers / The Flint Hills ecoregion in Kansas, USA, represents the largest remaining tract of native tallgrass prairie in North America. Anthropogenic landscape change (e.g., urbanization, agricultural production) is affecting native biodiversity in this threatened ecosystem. Our understanding of how landscape change affects spatial distributions of carnivores (i.e., species included in the Order ‘Carnivora’) in this ecosystem is limited. I investigated the influence of landscape structure and composition on site occupancy dynamics of 3 native carnivores (coyote [Canis latrans]; bobcat [Lynx rufus]; and striped skunk [Mephitis mephitis]) and 1 nonnative carnivore (domestic cat, [Felis catus]) across an urbanization gradient in the Flint Hills during 2016-2017. I also examined how the relative influence of various landscape factors affected native carnivore species richness and diversity. I positioned 74 camera traps across 8 urban-rural transects in the 2 largest cities in the Flint Hills (Manhattan, pop. > 55,000; Junction City, pop. > 31,000) to assess presence/absence of carnivores. Cameras were activated for 28 days in each of 3 seasons (Summer 2016, Fall 2016, Winter 2017) and I used multisession occupancy models and an information-theoretic approach to assess the importance of various landscape factors on carnivore site occupancy dynamics. Based on previous research in other ecosystems, I expected a negative relationship between both coyote and bobcat occurrence with increasing urban development but a positive relationship for domestic cat and skunk occurrence with increasing urban landcover. I also predicted grassland landcover to positively influence site occupancy for all carnivores except domestic cats. I expected that coyotes, the apex predator in this ecoregion, may limit domestic cat distributions through intraguild competition. Thus, I predicted a negative relationship between site occupancy of domestic cats and coyote occupancy probabilities. Because urban development results in habitat loss and fragmentation, I expected native species richness and diversity to decline with increased urban development. Coyotes had lower occupancy and colonization rates in areas with increased urban landcover. Bobcat occupancy was insensitive to urban landcover and colonization rates were greater in grassland landcover and row-crop agriculture fields. Site occupancy of bobcats was highly influence by forested areas and greater edge densities. Contrary to my hypothesis, striped skunk occupancy and colonization rates were negatively related to urban landcover. As expected, domestic cats were more likely to occur in and colonize sites with increased urban development and less likely to occur at sites with high coyote occupancy probabilities. Native carnivore species diversity and richness were negatively related to urban landcover. Occupancy dynamics of carnivores were shown to be influenced by landscape structure and composition as well as intraguild interactions. My results show urban landcover has a strong influence on the spatial distributions of carnivores in the northern extent of the Flint Hills.
6

It All Comes Out in the Wash: Mammal Use of Riparian Corridors in Semi-Arid Sonora, Mexico

January 2020 (has links)
abstract: Land use change driven by human population expansion continues to influence the integrity and configuration of riparian corridors worldwide. Wildlife viability in semi-arid regions depend heavily on the connectivity of riparian corridors, since water is the primary limiting resource. The Madrean Archipelago in northern Mexico and southwestern United States (US) is a biodiversity hotspot that supports imperiled wildlife like jaguar (Panthera onca) and ocelot (Leopardus pardalis). Recent and ongoing infrastructure developments in the historically understudied US-México borderlands region, such as the border wall and expansion of Federal Highway 2, are altering wildlife movement and disconnecting essential habitat. I used wildlife cameras to assess species occupancy, abundance, and related habitat variables affecting the use of washes as corridors for mammals in semi-arid Los Ojos (LO), a private ranch within a 530 km2 priority conservation area in Sonora, México located south of the border and Federal Highway 2. From October 2018 to April 2019, I deployed 21 wildlife cameras in five different riparian corridors within LO. I used single- season occupancy models and Royal Nichols abundance models to explore the relationship between habitat variables and use of riparian corridors by mammal communities of conservation concern within this region. Twenty-one mammal species were recorded in the study area, including American black bear (Ursus americanus), white-tailed deer (Odocoileus virginianus) and the first sighting of jaguar (Panthera onca) in this region in 25 years. For the 11 medium- and large-bodied mammals recorded, habitat variables related to perennial river characteristics (distance to river, weekly water, and site width) and remoteness (distance from highway, elevation, and NDVI) were important for occupancy, but the direction of the relationship varied by species. For commonly observed species such as mountain lion (Puma concolor) and white-nosed coati (Nasua narica), topographic variety was highly informative for species abundance. These results highlight the importance of habitat diversity when identifying corridors for future protection to conserve wildlife communities in semi-arid regions. Additionally, this study provides robust evidence in support of mitigation measures (e.g. funnel fencing, over- or under- passes) along Federal Highway 2, and other barriers such as the border wall, to facilitate wildlife connectivity. / Dissertation/Thesis / Masters Thesis Biology 2020
7

Effects of Habitat, Density, and Climate on Moose and Winter Tick Ecology in the northeastern U.S.

Berube, Juliana 25 March 2024 (has links) (PDF)
Over the past several decades, moose (Alces alces) populations in New England have been in decline due to winter tick (Dermacentor albipictus) parasitism. Winter ticks have been known to infest moose, with over 90,000 ticks being recorded on a single moose. These severe infestations, known as epizootics, are associated with high annual calf mortality rates (> 50%) and reductions in annual productivity (adult calving and twinning rates < 60% and 5%, respectively). Given this, it is increasingly important to effectively monitor moose and winter ticks to address consistent population decline of moose due to winter tick epizootics. The objectives of this work were to measure off-host winter tick abundance and associated environmental variables and compare off-host tick abundance in relation to moose abundance. To assess moose and winter tick abundance, I used a combination of camera traps and winter tick sampling. I set an array of 60 cameras across central-western Massachusetts, which contribute data to the Northeast Wildlife Monitoring Network. I used a plot-based sampling strategy that is effective for heterogenous habitat types to sample winter ticks at sites in western and central Massachusetts as well as the White Mountain National Forest and Umbagog National Wildlife Refuge in New Hampshire. The Penobscot Nation developed the tick sampling approach and contributed additional winter tick data from their sovereign trust lands in Maine. I used N-mixture models to generate estimates of tick abundance for each of the three study areas. Results from this study can inform monitoring strategies for ticks, predict epizootic severity, and develop tools to mitigate threats to moose. This is important for managers looking to prevent further declines in moose populations due to winter ticks and tribes seeking to maintain populations for sustenance.
8

Monitoring and Conserving Wildlife Communities across Northern Botswana

Rich, Lindsey N. 27 September 2016 (has links)
To develop effective conservation planning and mitigate biodiversity loss, standardized metrics for monitoring and assessing biodiversity are needed. This information is particularly vital in Botswana, where knowledge of many of the diverse wildlife populations is lacking. To address this knowledge gap, my dissertation research evaluated the distributions, densities, and ecology of the wildlife community in northern Botswana, with a focus on terrestrial carnivore species given their importance both ecologically and economically. My objectives were threefold: 1) estimate the distributions of the mammal community (n = 44 species) and evaluate community, group, and species-specific responses to anthropogenic and environmental variables, 2) test whether the presence of intraguild species or resource availability had a larger influence on the seasonal distributions of carnivore species, and 3) simultaneously estimate the population densities of 7 carnivore species. To accomplish these objectives, I completed a multi-year camera trap survey in a 1,154-km2 study area and analyzed the data using occupancy models (single and multi- species) and spatially explicit capture-recapture models. Estimates of species richness ranged from 8 to 27 unique species, species had a mean occurrence probability of 0.32 (95% credible interval = 0.21–0.45), and estimated densities ranged from 1.8 aardwolves (Proteles cristata) to 12.7 spotted hyenas (Crocuta crocuta) per 100 km2. The occupancy and richness of terrestrial mammals was negatively associated with human disturbance and in general, positively associated with open grasslands/floodplains. Carnivore species, specifically, tended to have greater species richness and larger population densities in open habitats than in closed. I also found carnivore distributions were positively associated with the detection rate of intraguild competitors and predators, suggesting competitor/predator avoidance did not play a large role in shaping carnivore community structure. My research highlights the pivotal role protected areas and grasslands play in conserving wildlife populations in northern Botswana. Additionally, my research helps progress camera trap analyses from single to multi-species assessments. Broader application of this multi-species approach would likely result in a better understanding of wildlife and carnivore communities which in turn, may help inform management actions aimed at addressing the loss of wildlife populations globally. / Ph. D.
9

Amphibian Occurrence on South Okanagan Roadways: Investigating Movement Patterns, Crossing Hotspots, and Roadkill Mitigation Structure Use at the Landscape Scale

Crosby, Jonquil January 2014 (has links)
Road expansion and increased traffic likely exacerbates barriers to amphibian migration and dispersal. Within British Columbia’s south Okanagan valley there is particular concern that the COSEWIC-listed blotched tiger salamander (Ambystoma mavortium melanostictum) and Great Basin spadefoot (Spea intermontana) are vulnerable to road effects in their annual movements from upland overwintering habitat to lowland breeding areas. My study utilizes a before after control impact approach to assess amphibian movement and population threats across this highway-bisected landscape. Throughout the spring and summer of 2010-2012, fifty two kilometers of roadways (31 km of highway, 21 km of paved backroad) were repeatedly surveyed from the Canada-USA border to north of Oliver, BC; surveys were carried out utilising vehicles and on foot. Along Highway 97, a three kilometer four-lane highway expansion project was constructed through 2010 and open to traffic use in 2011. Adjacent to a floodplain, survey effort was focused throughout this transect for informed roadkill mitigation structure placement and ongoing ecopassage effectiveness monitoring. Automated camera trap monitoring of culverts within highly concentrated amphibian road hotspots during spring and summer 2011 (three culverts) and 2012 (two culverts) resulted in over eight hundred amphibian culvert events observed. Two sample Wilcoxon tests revealed differences between years in amphibian occurrence between 2010 and 2012 (W = 4679.5, p= 0.02), and mortalities among transect areas, with the largest differences between years within the Osoyoos passing lanes transect. Amphibian mortalities within the passing lanes transect were significantly reduced with the implementation of mitigation structures (x̅2010= 13.2 ± 32.5, x̅2011= 4.7 ± 12.8, x̅2012= 2.3 ± 7.3; 2010 vs. 2012: W= 1535.5, p< 0.001). Roadkill mitigation structures proved effective in observed amphibian occurrence of the entire passing lanes stretch as well as at distances 100 m and 200 m from observed culverts. Double fenced areas resulted in a 94% reduction in amphibian road occurrence. Five species of amphibians were observed over the three survey years (4051 road incidences over 657 survey hours): Pacific chorus frog (Pseudacris regilla), Western toad (Anaxyrus boreas), long-toed salamander (Ambystoma macrodactylum) plus blotched tiger salamander and Great Basin spadefoot. This study aims to provide a better understanding of amphibian hotspots on roadways and ecopassage use within the south Okanagan. It may act as a catalyst to further wildlife-vehicle interaction studies with improved mitigation solutions for amphibian roadway fatalities.
10

Prostorová aktivita psíka mývalovitého (Nyctereutes procyonoides) v Zookoutku Malá Chuchle / Spatial Activity of Raccoon Dog (Nyctereutes procyonoides) in the Mini Zoo Malá Chuchle

Bušová, Tereza January 2016 (has links)
This thesis deals with monitoring of two raccoon dogs (Nyctereutes procyonoides) by camera traps at Prague minizoo Malá Chuchle in the period from February to May 2016. Activity and behaviour of both raccoon dogs is presented by charts and diagraphs for better understanding. Overview of Canidae family, its description and area, is included in this thesis. KEYWORDS racoon dog, Nyctereutes procyonoides, activity, ethogramm, camera trap

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