Search results
Pages
- Title
- Temperature preference and distribution of juvenile Arctic grayling (Thymallus arcticus) in the Williston watershed, British Columbia Canada.
- Contributors
- Sarah C. F. Hawkshaw (author), Mark Shrimpton (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- The habitat requirements of juvenile Arctic grayling (Thymallus arcticus) were assessed in the Williston watershed, British Columbia, where the population is currently red-listed (critically imperiled). Temperature preferences of juvenile Arctic grayling was assessed behaviorally using a shuttlebox system, and an information theoretic approach analysis of logistic regression models was used to evaluate the influence of environmental factors on the distribution of juvenile Arctic grayling throughout the Williston watershed. Temperature preference of juvenile Arctic grayling did not vary between the two tributaries in the watershed (p = 0.77) and the average preferred temperature was 16.84 ± 0.66 °C (n = 28). Comparisons of the preferred temperature to ambient water temperatures suggested that juvenile Arctic grayling will avoid areas where maximum water temperature is above the preferred temperature. There was a positive association between juvenile Arctic grayling occurrence and stream order (SO) and stream order multiplied by distance from the Williston reservoir (SDRxSO), as well as a negative association with the mean daily water temperature variance (varT) and average water temperature (aveT). Overall these findings suggest that large river systems are important juvenile Arctic grayling habitat and management decision should be made to ensure protection of this habitat throughout the range of this species. --P. ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2011
- Title
- Interrelationships between weather, parasitic insects, and barren-ground caribou (Rangifer tarandus groenlandicus) behaviour in Northwest Territories and Nunavut.
- Contributors
- Leslie A. Witter (author), Christopher Johnson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- The Bathurst barren-ground caribou (Rangifer tarandus groenlandicus) herd decreased by 90% from 1986-2009. Increased intensity of insect harassment due to climatic warming is hypothesized as a factor contributing to the decline. I monitored weather, trapped insects, and recorded caribou behavior during 2007-2009. Oestrid fly (Oestridae) presence, and mosquito (Culicidae) and black fly (Simuliidae) activity/abundance were best explained by temperature, wind speed, light intensity, barometric pressure, relative humidity, vegetation, topography, and location. Time of day and growing degree days also affected mosquito and black fly levels. Conditions favouring mosquito activity declined, while those favouring black and oestrid fly activity increased since the mid 1980s. Mosquitoes had relatively little effect on caribou behavior. Insect avoidance increased when oestrids were present or black flies were active at moderate-high levels. Understanding differential effects of macroparasites on Rangifer behavior is necessary to predict herd dynamics in the context of a changing climate across northern Canada. --P.ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2011
- Title
- Carbon budget of forest products harvested from mountain pine beetle-attacked forests in the Prince George region
- Contributors
- Wyatt Stanley Klopp (author), Art Fredeen (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- The risk of the mountain pine beetle (MPB Dendroctonus ponderosae Hopkins) attacked forests contributing to global climate change has many stakeholders looking for potential mitigation solutions in British Columbia, Canada. To date, these efforts maintain the notion of proactive forest management, yet lack a clear understanding of the contribution of forest products to mitigating greenhouse gas (GHG) emissions. My study addressed this ambiguity by estimating the GHG emissions attributable to current and proposed forest products harvested from MPB-attacked forests. My findings found relative differences between two distinct forest products (lumber, pellets), but ultimately their outcomes are contextually driven. Moreover, the cut-off criteria and assumptions governing biogenic GHG emissions (i.e. carbon neutrality) were found to have a large impact on the industrial forest C budget. The lasting contribution of this thesis is in its reconciliation of the current dichotomy in the fields of environmental science and policy with respect to the contribution of forest products to forestry's efforts in mitigating climate change. --Leaf ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2016
- Title
- Response of Scouler's willow (Salix scouleriana) to mechanical brushing: Implications to the quality of winter browse for moose (Alces alces).
- Contributors
- Roy Van Rea (author), Michael P. Gillingham (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 1999
- Title
- Lichen and bryophyte diversity, nitrogen and carbon dioxide exchange from sub-boreal spruce forest floors in central British Columbia.
- Contributors
- Rachel S. Botting (author), Arthur Fredeen (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2006
- Title
- The relationship between climate and outbreak dynamics of Dothistroma needle blight in northwest British Columbia, Canada.
- Contributors
- Cedar Welsh (author), Kathy Lewis (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2007
- Title
- Spatial associations between infestations of mountain pine beetle and landscape features in the Peace River Region of British Columbia.
- Contributors
- Honey-Marie C. de la Giroday (author), Brian Aukema (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- An immense outbreak of the mountain pine beetle, Dendroctonus ponderosae Hopkins, currently covers a cumulative area of 14.5 million hectares of mature pine forests across the provinces of British Columbia and Alberta, Canada. In 2004, the first outbreaking populations of mountain pine beetle were observed in northeastern British Columbia, an area not considered part of the insect's native range. My thesis examines how landscape features and their orientation influence establishment patterns of the insect. Mountain pine beetle spread between 2004 and 2006 in patterns similar to a propagating wave, likely due to long-distance dispersal into the region. Large glacially-eroded valleys, canyons, deeply incised streams, local and midslope ridges or small hills in valleys and plains, and open slopes were often positively associated with infestations, providing evidence that the interaction of meso-scale convective currents and topography can mediate patterns of establishment. The orientation of landscape features also influenced establishment, as southwest-facing areas and linear features aligned in northeast-southwest directions were associated with increased densities of infestations in 2006. Management activities were typically associated with a decline in the density of mountain pine beetle infestations in the following year, indicating that such activities were effective in preventing short-distance dispersal of the insect. I found no evidence that anthropogenic activities such as transport and storage of infested material increased establishment of mountain pine beetle across the research area. These results may be used to prioritize preemptive treatments in mountainous regions in the absence of long-distance inputs of mountain pine beetle into expanding ranges. --P.ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2010
- Title
- Trade-offs in the early development of tree swallows (Tachycineta bicolor): offspring characteristics, offspring quality, and parental care
- Contributors
- Sophia A. Unger (author), Russell Dawson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- Life-history theory predicts that because organisms have limited resources available to them, they must make decisions to prudently allocate resources in a way that maximizes fitness. Therefore, there is expected to be a trade-off between current reproductive effort and future survival and reproduction, with those individuals investing in a current breeding attempt doing so at a cost to their own survival and/or future fecundity. Altricial birds rearing young are consequently expected to be prudent in their allocation of resources between brood-maintenance and self-maintenance, and their allocation choices may be influenced by numerous offspring characteristics that potentially indicate offspring "quality" or condition. My thesis had three main goals: 1) to understand if the smallest nestling tree swallows in a nest are of inherent poor "quality", or if they are the smallest simply due to being outcompeted by their older and larger siblings 2) to investigate whether, in an environment with parasites, it is the parents or their offspring who bear the costs associated with parasitism and 3) to better understand the function of gape and flange colouration in nestling tree swallows. Overall, I wanted to understand how each of these nestling characteristics affect, and are affected by, parental life-history trade-offs. By pairing observational data with a cross-fostering experiment, I determined that both total egg mass and yolk mass increased with order of laying. Nestlings that hatched earlier in the hatching sequence and were manipulated to be smaller within the size hierarchies in nests performed in a similar fashion as if they had retained their size advantage, but had lower immune responses, which may be because these earlier-hatched nestlings hatched from earlier-laid eggs with smaller yolks. By manipulating parasite levels in nests and then comparing nestling immune function and growth, and parental provisioning rates with control nests in a three-year study, I observed no significa
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2016
- Title
- Responses of mountain goats to heliskiing activity: Movements and resource selection.
- Contributors
- Becky A. Cadsand (author), Michael Gillingham (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- Heliskiing activity has increased in many areas of mountain goat (Oreamnos americanus) range how this activity affects movements and resource use, however, is poorly understood. In 2007 - 2010, I examined locations and movements of 11 GPS-collared female mountain goats relative to activity of GPS-equipped helicopters in northwest British Columbia. Mountain goats exhibited anomalous movements in the 48 h following helicopter approaches within 2 km, regardless of whether helicopters were visible to the animals. Mountain goats were not displaced by the disturbances, however, and seasonal movement rates did not increase with heliskiing exposure. Animals did not avoid areas of helicopter activity, but several animals in areas of high heliskiing activity selected strongly for security terrain. When exposure to helicopter activity is <1h/month, I recommend pre-planning measures be undertaken to ensure 1,500-m separation distances between heliskiing activity and mountain goat range. At higher exposures, separation distances should extend to 2 km. --Leaf ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2013
- Title
- Causes and consequences of blue-green eggshell colour variation in mountain bluebirds (Sialia Currucoides)
- Contributors
- Jeannine A. Randall (author), unknown unknow (Thesis advisor), University of Northern British Columbia College of Science and Management (Degree granting institution), unknown unknown (Committee member)
- Abstract
- The function and evolution of ornamental traits has been a major focus of evolutionary ecology. Despite this, female ornaments have received relatively little consideration, and are still poorly understood relative to those produced by males. However, presently, there is much interest in determining how sexual selection shapes female phenotypes. Blue-green eggshell colour, derived from the antioxidant pigment biliverdin, is one attribute produced by female birds that has come under scrutiny as a potentially sexually selected trait. Based on the possibility that biliverdin is limited and costly to produce, the sexually selected egg colour hypothesis predicts that blue-green egg colour has evolved in species with biparental care as an advertisement of female quality that elicits increased paternal effort from their social mate... .
- Discipline
- NRES-Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2016
- Title
- Survival, growth and the possible environmental impacts of introduced blue mussels (Mytilus spp.) in Georgia Strait, British Columbia: Implications for mussel aquaculture.
- Contributors
- Jenia F. Yanick (author), Daniel Heath (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2002
- Title
- Detection of shifts in microbial functional gene (nosZ and nifH) distribution due to long term warming of a high Arctic soil.
- Contributors
- Jennifer K. M. Walker (author), Keith Egger (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2007
- Title
- Reproductive success and habitat selection of sharp-tailed grouse (Tympanuchus phasianellus) in the Peace River region, northeast British Columbia.
- Contributors
- Alicia D. Goddard (author), Russell Dawson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2007
- Title
- Ground beetles (coleoptera: carabidae) of the Chun T'oh Whudujut Park in eastern British Columbia, Canada, and their use as bioindicators of disturbance
- Contributors
- Ian Higgins (author), Brent Murray (thesis advisor), Lisa Poirier (thesis advisor), Daniel Erasmus (committee member), Staffan Lindgren (committee member)
- Abstract
- The Chun T’Oh Wudujut is a provincial park located in the Interior Cedar-Hemlock biogeoclimatic zone. My objective was to assess the use of carabid beetles as bioindicators of change in this unique interior temperate rain forest ecosystem. Using a combination of morphotyping and DNA barcoding, I examined the diversity of carabid beetles in three different habitat types: clear-cuts, undisturbed old growth, and disturbed old growth subject to frequent human traffic. Nineteen species of carabid were observed, with the highest diversity occurring in clear-cut sites. Carabid diversity in both old growth habitats was similar, but differed from that in the clear-cuts. Temperature and relative humidity proved more variable in clear-cut sites; this may impact carabid biodiversity, and should be measured in future bioindicative studies. Several species of carabid beetles (alone and in combination) were identified as possible bioindicators, including Scaphinotus marginatus, Trechus chalybeus, Pterostichus herculaneus, and Pterostichus riparius.
- Discipline
- NRES-Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2019
- Title
- Effects of supplementary nitrogen on biomass and nitrogen accumulation in the sundew Drosera capensis L.
- Contributors
- Brian M. Bruzzese (author), University of Northern British Columbia (Degree granting institution)
- Abstract
- The effect of nutrient supplementation on biomass and nitrogen accumulation in the insectivorous plant Drosera capensis L. was studied under laboratory conditions using supplementary feeding of ammonium chloride (Nr4CI) to plant leaf surfaces. The nitrogen solution used was based on a standard concentration of 157.6 mM NH4CI. Drosera capensis did not differ significantly in biomass or nitrogen accumulation from concentrations of 50%, 75%, 100%, 150%, or 200% of nutrient fertilizer when applied to the foliage. Reproductive structures were observed in higher numbers in those plants treated with higher concentrations of Nr4Cl but no relationship was found between reproductive structures and biomass or nitrogen concentrations. The results of this experiment potentially indicate that D. capensis can grow and initiate reproductive structures without additional nutrients above which already exist in the soil mixture. The results also suggest that D. capensis does not readily absorb NH4CI through its leaves.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2002
- Title
- Use and selection at two spatial scales by female moose (alces alces) across central British Columbia following a mountain pine beetle outbreak
- Contributors
- Matthew Scheideman (author), Michael Gillingham (thesis advisor), Katherine Parker (committee member), Douglas Heard (committee member), University of Northern British Columbia (Degree granting institution)
- Abstract
- Moose are a keystone species and play a substantive role in predator-prey systems, nutrient cycling, and forest succession. Following a mountain pine beetle (MPB) spread across British Columbia, I quantified seasonal home-range selection, home-range size and daily movements, and within home-range selection of GPS-collared female moose in three study areas. I used case-matched logistic regressions with individual seasonal home-ranges, and mixed-effects logistic regressions for seasonal locations of female moose to determine habitat selection at two spatial scales. Individual variation was evident at both home-range and within-home-range scales. Female moose selected lodgepole pine-leading stands at both spatial scales regardless of mass die-off due to MPB. Clear-cuts following the MPB outbreak were avoided in drier locations, and trade-offs between cover and browse were evident where disturbance due to salvage logging was highest. My findings indicate that MPB salvage-logging reduced moose habitat, and thereby, influenced selection by female moose.
- Discipline
- NRES-Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2018
- Title
- Habitat use and selection by male and female moose (Alces alces) in a boreal landscape.
- Contributors
- Alice McCulley (author), Katherine L. Parker (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- Moose (Alces alces) is a keystone species in boreal landscapes. I quantified seasonal range sizes, movement rates, and use of elevation and land cover for male and female moose in south-central Yukon. I used individual and pooled resource selection functions to define the influence of land cover, topography, predation risk, and harvest vulnerability on habitat selection. Seasonal changes affected use and selection more than gender or reproductive status (females with and without calves). High use and positive selection for shrub-dominated land-cover classes by all individuals in all seasons affirmed forage as a primary force driving seasonal selection patterns. Variation in selection among individuals was highest during the growing seasons and least during late winter, when options were constrained by climatic factors. These findings from telemetered moose generally corresponded with models based on local knowledge-based habitat suitability indices and post-rut locations from aerial surveys and they contribute to land-use planning processes. --Leaf ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2015
- Title
- Distribution and movements of canyon-dwelling mountain goats along Pinto Creek, Alberta.
- Contributors
- Donna Georgetta Harrison (author), Michael Gillingham (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- No abstract available.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 1999
- Title
- Lichen refugia within sub-boreal spruce forests: The role of riparian alder swales.
- Contributors
- Matthew J. D. Doering (author), Darwin Coxson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- Wetland swales, corridors of willows and alders adjacent to streams and seepage areas, may play a role as refugia for lichen biodiversity because likely escape stand replacement disturbance such as fire more often than adjacent upland forest, especially moist to drier sub-boreal and boreal landscapes, and are also not disturbed by forest harvesting. Macrolichen communities in 75 alder-dominated wetland swales along an east (wet) to west (dry) gradient in the Sub-Boreal Spruce biogeoclimatic zone of central interior British Columbia were examined. Spatial analysis of wetland swales indicated an average size of 20.5 m wide by 854 m long (following patch contours). A total of 43 macrolichen species (and six other macrolichen genera) were found in the alder dominated sites, with a maximum of 30 taxa present in the richest site. The macrolichen diversity of alder swales included the old-growth associated lichens Lobaria scrobiculata, L. retigera, Nephroma isidiosum, and Sticta limbata. Canonical Correspondence Analysis identified mean annual temperature and abundance of large stems (dbh > 10 cm) as significant explanatory variables for chlorolichens and mean annual precipitation and age of adjacent conifer forest as significant explanatory variables for the majority of the cyanolichens. Regional precipitation gradients explained the exclusion of many lichen species from both the most westerly and most easterly swales, with drier summer conditions and heavy winter snowpack, respectively, being major limiting factors. Within sites, lichens preferentially occupied large leaning stems, which provided greater precipitation interception and long-lived substrates for many old-growth associated lichen species. Physiological analyses of six common cyanolichens indicated low contributions of cyanolichens to the nitrogen budgets of alder swales. However, adaptations and niches of each of the cyanolichens were revealed. Nephroma parile was the best adapted to the widest range of conditions, followed by Lobaria pulmonaria. Pseud
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2010
- Title
- Factors influencing habitat use by juvenile interior Fraser coho.
- Contributors
- Kyla D. Warren (author), Mark Shrimpton (Thesis advisor), University of Northern British Columbia (Degree granting institution)
- Abstract
- The influence of physical and biological factors on juvenile interior Fraser coho (Oncorhynchus kisutch) habitat use was examined within the Horsefly River watershed using three approaches. Otolith microchemistry was used to assess potential movement of juveniles throughout the watershed. This analysis showed evidence of an average of 3.5 movements to different habitats within the Horsefly watershed during the juvenile lifestage. It was not possible to track the location and timing of most of those migrations, but some appear to be the result of a movement into small tributaries in late summer and winter. A microhabitat model was used to determine physical characteristics of habitats where juvenile coho were captured. Low velocity, small stream width, a greater proportion of gravel as substrate, and high instream and overhead cover were strongly related to the distribution of juvenile coho within the streams examined. A behavioural study in an artificial stream channel assessed the type of interactions that occur among juvenile coho. Juvenile interior Fraser coho exhibited little evidence of territoriality, contrasting with published reports of highly territorial juvenile coho behavior in coastal systems. The lack of territoriality of the interior Fraser coho studies, their frequent migrations, and their strong association with cover, all suggest interior Fraser coho exhibit different habitat use patterns than coho in coastal streams. The difference in habitat use and requirements may influence the effectiveness of current management strategies, many of which are based solely on criteria from coastal coho research studies. --P. ii.
- Discipline
- Biology
- Content Model
- info:fedora/ir:thesisCModel
- Date added
- 2010