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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.
11

Use of fecal DNA to estimate population demographics of the Boreal and Southern Mountain ecotypes of woodland caribou

Hettinga, Peter N. 09 September 2010 (has links)
This study looked at the efficacy of using woodland caribou fecal pellets as a source of DNA to identify sampled animals and estimate population demographics. Fecal pellet samples were collected using systematic surveys of woodland caribou ranges in Jasper National Park, Alberta and the North Interlake region, Manitoba. Collection of pellet samples took place when snow was present to allow for tracking and location of caribou cratering areas and to obtain good quality DNA. DNA was amplified at ten polymorphic loci and one sex-specific primer. To estimate population size (N ̂) and population growth rate (λ), mark-recapture models were used. Model assumptions were evaluated and tested by stratifying available samples based on herd and gender information. In using the Mh (jackknife) model, the population sizes for south Jasper National Park were estimated at 125 animals in 2006-2007 (95% CI: 114, 143), 91 animals in 2007-2008 (95% CI: 83, 105) and 134 animals in 2008-2009 (95% CI: 123, 152); comparable to the mark-resight population estimates calculated over the same sampling periods. Genetic diversity indices for the different herds in Jasper National Park presented a lower genetic diversity for the smaller Maligne and Brazeau herds when compared to the larger Tonquin and A La Peche herds. Use of population assignment tests on samples collected in Jasper National Park indicated considerable admixture between the different herds despite earlier telemetry work demonstrating strong herd fidelity. The North Interlake population was estimated at 134 animals (95% CI: 122,151) in 2006-2007 and 106 animals (95% CI: 97, 121) in 2007-2008. Using data collected between 2005 and 2008, population growth rate for North Interlake was estimated at 0.83 (90% confidence interval: 0.65, 1.02). As a λ below 1 indicates a declining population, continue monitoring of the North Interlake herd is highly recommended. This studied clearly showed that the sampling of fecal DNA is a reliable and noninvasive alternative to monitoring woodland caribou population sizes and trends in the boreal and mountain regions.
12

Seasonal Habitat Selection by Resident and Translocated Caribou in Relation to Cougar Predation Risk

Leech, Heather 17 April 2015 (has links)
Mountain caribou, an arboreal lichen-feeding ecotype of woodland caribou (Rangifer tarandus caribou), have been extirpated from much of their historic range. Mountain caribou are federally listed as Endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) and red-listed by the BC government. Habitat loss and fragmentation of old growth forest is the ultimate cause for population declines. Yet, predation, linked to apparent competition, is the proximate cause for high rates of mortality. One of the most imperiled populations resides in the Purcell Mountains of BC, which was experimentally augmented in 2012 with 19 northern caribou from northern BC. The caribou-predator literature predominantly focuses on the relationship between caribou and wolves (Canis lupus) in northern caribou populations. However, cougars (Puma concolor) have been identified as a major predator of Purcells-South (PS) caribou, yet caribou-cougar interactions remain largely unstudied. I evaluated cougar predation risk in space and time on resident and translocated caribou in the Purcell Mountains. To do so, I determined biologically relevant seasons for resident, donor (i.e. not translocated) and translocated caribou, and cougars. I then used these seasons to investigate seasonal patterns of movement and habitat use between the three groups of caribou and cougars. Next I used resource selection functions (RSFs) to estimate habitat based seasonal variation in predation risk. I used these RSFs to compare the seasonal habitat selection and risk to cougar predation between resident and translocated caribou. Five resident caribou seasons and two cougar seasons were defined. Translocated caribou displayed inconsistent movement behavior with no clear seasonal pattern. Resident caribou remained at high elevations year-round and selected for low risk cougar habitat during the calving season at the home range scale and year-round at the landscape scale. Translocated caribou displayed risky behaviour throughout the study period by traveling to mid to low elevations and habitats selected by cougars. Translocated caribou displayed the same general pattern of elevational movement as their northern conspecifics, spending the majority of their time at lower elevations than resident caribou. Of the 19 translocated caribou, 17 (89%) died during the study, six of which were preyed upon by cougars, two by wolves, and the remainder due to accidents or unknown causes. In summary, translocated caribou did not adopt the predator avoidance or habitat selection strategies of resident caribou. I recommend that future efforts to augment small caribou populations use donor caribou experienced with similar predators and that possess comparable seasonal habitat use to the recipient population. However, because most suitable donor populations are declining, a soft-release of captive-reared mountain caribou might be the best option for mountain caribou recovery efforts. / Graduate / 0366 / 0329
13

Long-term Habitat Trends in Barren-ground Caribou

White, Lori 28 January 2013 (has links)
Global and local climate patterns may affect barren-ground caribou (Rangifer tarandus groenlandicus) populations. I predicted global climate changes to be correlated with periods of population decline, and local changes to be more pronounced on the habitat of caribou with a declining population. In chapter 1, the Arctic Oscillation (AO), changes in normalized difference vegetation index and phenology were used as measures of global and local climate. In chapter 2 environmental variables and caribou presence points were used to build Maxent habitat models. There was no consistent correlation with the positive AO phase and periods of population decline, or phenology trends and the habitat of caribou with a declining population. Maxent models underestimated the amount of suitable habitat spatially and failed to model suitable habitat temporally. This thesis is the first to look at a range of density-independent variables over a long time period and model suitable habitat for multiple herds.
14

Use of fecal DNA to estimate population demographics of the Boreal and Southern Mountain ecotypes of woodland caribou

Hettinga, Peter N. 09 September 2010 (has links)
This study looked at the efficacy of using woodland caribou fecal pellets as a source of DNA to identify sampled animals and estimate population demographics. Fecal pellet samples were collected using systematic surveys of woodland caribou ranges in Jasper National Park, Alberta and the North Interlake region, Manitoba. Collection of pellet samples took place when snow was present to allow for tracking and location of caribou cratering areas and to obtain good quality DNA. DNA was amplified at ten polymorphic loci and one sex-specific primer. To estimate population size (N ̂) and population growth rate (λ), mark-recapture models were used. Model assumptions were evaluated and tested by stratifying available samples based on herd and gender information. In using the Mh (jackknife) model, the population sizes for south Jasper National Park were estimated at 125 animals in 2006-2007 (95% CI: 114, 143), 91 animals in 2007-2008 (95% CI: 83, 105) and 134 animals in 2008-2009 (95% CI: 123, 152); comparable to the mark-resight population estimates calculated over the same sampling periods. Genetic diversity indices for the different herds in Jasper National Park presented a lower genetic diversity for the smaller Maligne and Brazeau herds when compared to the larger Tonquin and A La Peche herds. Use of population assignment tests on samples collected in Jasper National Park indicated considerable admixture between the different herds despite earlier telemetry work demonstrating strong herd fidelity. The North Interlake population was estimated at 134 animals (95% CI: 122,151) in 2006-2007 and 106 animals (95% CI: 97, 121) in 2007-2008. Using data collected between 2005 and 2008, population growth rate for North Interlake was estimated at 0.83 (90% confidence interval: 0.65, 1.02). As a λ below 1 indicates a declining population, continue monitoring of the North Interlake herd is highly recommended. This studied clearly showed that the sampling of fecal DNA is a reliable and noninvasive alternative to monitoring woodland caribou population sizes and trends in the boreal and mountain regions.
15

Motorized backcountry recreation and stress response in Mountain Caribou (Rangifer tarandus caribou)

Freeman, Nicola L. 11 1900 (has links)
Mountain caribou (Rangifer tarandus caribou) are endangered in British Columbia and motorized backcountry recreation has been identified as a potential threat to their persistence. My objective was to test if fecal glucocorticoids (GCs), indicative of physiological effects of ecological stress in wildlife, could be used as a non-invasive tool to quantify stress response in free-ranging caribou exposed to motorized recreation. I validated an enzyme-linked immunosorbent assay (ELISA) to measure concentration of fecal GCs for R. tarandus using an adrenocorticotropic hormone (ACTH) challenge experiment on captive reindeer exposed to extreme variation in winter weather. Female reindeer expressed elevated fecal GCs 9-11 hrs after ACTH injection. Males showed no detectable increase, perhaps due to underdosing. Fecal GCs varied markedly in both sexes in response to natural variation in weather. Overall, my results indicated fecal assays can be used to track biologically meaningful changes in adrenal activity in R.tarandus. I investigated the effects of motorized recreation on stress hormone production by measuring GCs in feces of mountain caribou exposed to snowmobile and heli-ski activity. Concentrations of fecal GCs in snowmobile and heli-ski areas were higher than those measured from caribou in areas where motorized recreation was not allowed. Caribou sampled up to 4km. 8km and I0 km distant from snowmobile activity showed elevated fecal GCs when compared to those sampled further from snowmobile activity areas. Other variables with a significant effect on fecal GCs included reproductive state, snow, aspect. minimum ambient temperature, and daily temperature range. My study indicates that measurement of fecal GCs provides a useful, noninvasive approach in the evaluation of physiological effects of environment, reproductive state, and human-induced stressors on free-ranging mountain caribou. Although research on many species indicates that chronically elevated GCs carry a variety of physiological costs, more study is needed to know whether GCs can be used as an index of human impact on population health or trend.
16

Variation in the blood chemical constituents of reindeer:significance of season, nutrition and other extrinsic and intrinsic factors

Säkkinen, H. (Hannele) 09 August 2005 (has links)
Abstract Reindeer management in the Fennoscandian area is currently facing challenges such as degradation of winter pastures, which may lead in the most severely affected areas to a concurrent decline in reindeer herd productivity. The use of often expensive supplementary feeding to prevent production losses has increased the demand for studies on the physiological effects of nutritional restriction and supplementary feeding. The knowledge obtained from such studies could be used, for example, to monitor the condition of reindeer in studies assessing herd productivity levels in different pasture conditions and management systems or sustainable use of pasture resources. In this thesis, the effects of season, year, pasture area, body mass, pregnancy and other extrinsic and intrinsic factors on the variation of blood chemical constituents of reindeer were studied in free-ranging animals under natural foraging conditions. The studied blood chemical constituents covered a wide range of parameters related to protein, carbohydrate, lipid and mineral metabolism. The same blood chemical constituents were studied in captive reindeer under defined feeding conditions, allowing an analysis of the effects of dietary protein, energy and mineral intake on the selected blood constituents and their comparison to a conventional measure of the animals' condition, live body mass. According to the results, free-ranging reindeer showed great variation in the concentrations of blood chemical constituents compared to the reference values of domesticated ruminants. Intrinsic factors such as body mass, pregnancy and age had only a minor influence on the variation of the studied parameters, whereas extrinsic factors such as season, year and pasture area, which were characterized by marked changes in environmental and nutritional conditions, explained the majority of the variation. The results obtained from captive animals in defined feeding conditions and from free-ranging animals foraging on natural pastures led to the conclusion that blood total proteins, albumin, urea, creatinine, urea:creatinine ratio, magnesium, inorganic phosphate and, to a lesser extent, globulins and albumin:globulin ratio responded to the changes in feed quality and availability and were the most suitable blood constituents to be used as nutritional biomarkers for reindeer.
17

Motorized backcountry recreation and stress response in Mountain Caribou (Rangifer tarandus caribou)

Freeman, Nicola L. 11 1900 (has links)
Mountain caribou (Rangifer tarandus caribou) are endangered in British Columbia and motorized backcountry recreation has been identified as a potential threat to their persistence. My objective was to test if fecal glucocorticoids (GCs), indicative of physiological effects of ecological stress in wildlife, could be used as a non-invasive tool to quantify stress response in free-ranging caribou exposed to motorized recreation. I validated an enzyme-linked immunosorbent assay (ELISA) to measure concentration of fecal GCs for R. tarandus using an adrenocorticotropic hormone (ACTH) challenge experiment on captive reindeer exposed to extreme variation in winter weather. Female reindeer expressed elevated fecal GCs 9-11 hrs after ACTH injection. Males showed no detectable increase, perhaps due to underdosing. Fecal GCs varied markedly in both sexes in response to natural variation in weather. Overall, my results indicated fecal assays can be used to track biologically meaningful changes in adrenal activity in R.tarandus. I investigated the effects of motorized recreation on stress hormone production by measuring GCs in feces of mountain caribou exposed to snowmobile and heli-ski activity. Concentrations of fecal GCs in snowmobile and heli-ski areas were higher than those measured from caribou in areas where motorized recreation was not allowed. Caribou sampled up to 4km. 8km and I0 km distant from snowmobile activity showed elevated fecal GCs when compared to those sampled further from snowmobile activity areas. Other variables with a significant effect on fecal GCs included reproductive state, snow, aspect. minimum ambient temperature, and daily temperature range. My study indicates that measurement of fecal GCs provides a useful, noninvasive approach in the evaluation of physiological effects of environment, reproductive state, and human-induced stressors on free-ranging mountain caribou. Although research on many species indicates that chronically elevated GCs carry a variety of physiological costs, more study is needed to know whether GCs can be used as an index of human impact on population health or trend. / Forestry, Faculty of / Graduate
18

Long-term Habitat Trends in Barren-ground Caribou

White, Lori January 2013 (has links)
Global and local climate patterns may affect barren-ground caribou (Rangifer tarandus groenlandicus) populations. I predicted global climate changes to be correlated with periods of population decline, and local changes to be more pronounced on the habitat of caribou with a declining population. In chapter 1, the Arctic Oscillation (AO), changes in normalized difference vegetation index and phenology were used as measures of global and local climate. In chapter 2 environmental variables and caribou presence points were used to build Maxent habitat models. There was no consistent correlation with the positive AO phase and periods of population decline, or phenology trends and the habitat of caribou with a declining population. Maxent models underestimated the amount of suitable habitat spatially and failed to model suitable habitat temporally. This thesis is the first to look at a range of density-independent variables over a long time period and model suitable habitat for multiple herds.
19

Environmental enrichment for zoo-housed Icelandic reindeer (Rangifer tarandus)

Kakol, Katarzyna January 2021 (has links)
Environmental enrichment is commonly used to improve the welfare of captive animals by offering options to increase behavioural diversity and normal behaviour patterns. The aim of this study was to assess if environmental enrichment has a positive effect on a group of four zoo-housed reindeer, Rangifer tarandus. Three types of environmental enrichment were used: food enrichment, olfactory enrichment, and tactile enrichment, with a spontaneous rotation to prevent habituation. Following a baseline period of ten days without enrichment, the animals’ behaviour was monitored for four months with enrichment. All behaviours shown by the reindeer during the study were categorized into locomotory behaviour, feeding behaviour, passive behaviour, social interactions, and behaviour towards enrichment. The overall level of activity of the reindeer almost doubled between the baseline period (40.8%) and the enrichment period (75.3%), with a significant increase in feeding behaviour (p < 0.001) and a significant decrease in passive behaviour (p < 0.001). Food enrichment had the strongest impact on the reindeer out of the three types of enrichment presented. Even though the reindeer showed a continuous interest towards tactile enrichment, it was low compared to the interest shown towards food enrichment. They also showed little interest in olfactory enrichment. Neophobia may explain the lack of interest by the reindeer to certain types of enrichment that were novel to them. Overall, the presentation of environmental enrichment made the behaviour of the captive reindeer clearly more similar to the behaviour of wild reindeer.
20

Black Bear Movements and Caribou Calf Predation in Newfoundland

Rayl, Nathaniel D 01 January 2012 (has links) (PDF)
The population trajectory of woodland caribou (Rangifer tarandus caribou) in Newfoundland is currently determined by low calf survival due to high predation rates during the first 6-8 weeks after parturition. Most caribou in Newfoundland congregate and give birth in open calving grounds; consequently, in order to investigate predator-prey interactions, design research, and develop mitigation strategies, the geographic extent of the caribou calving grounds must be properly identified. We used VHF telemetry locations of caribou calves, collected from 2003-2010, to determine the spatial and temporal extent of caribou calving grounds in three study areas in Newfoundland. We put GPS collars on 47 black bears (Ursus americanus) in 3 caribou ranges where bears are having a significant impact on caribou recruitment by preying on calves during the calving season. Bear movements were greatest during the calving season, potentially increasing encounters with calves. Some bears migrated to the calving grounds just prior to caribou parturition, indicating deliberate broad-scale selection of areas of high calf density. Bears displayed interannual fidelity to calving ground usage patterns during the calving season, with some bears using the calving grounds every year, while others did not. We estimated the probability of a bear spending time in the calving grounds during the calving season as a function of the bear’s sex and mean distance to the calving grounds with logistic regression. We found that as distance increased, the odds of a bear spending time in the calving grounds decreased, and that at any given distance the odds were greater for male bears than for female bears. Our results indicate that some bears in Newfoundland are likely caribou calf predators, while others are not, and that the sex and broad-scale distribution of bears influenced the probability of a bear participating in calf predation during the calving season. The probability distribution of calf-visiting bears could be used to develop management practices to mitigate the impact of bear predation on declining caribou herds in Newfoundland.

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