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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
Date added: 2017-03-30T17:09:21.087Z

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
Date added: 2017-03-30T17:08:33.261Z

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
Date added: 2017-03-29T17:30:28.668Z

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
Date added: 2017-03-29T17:32:32.482Z

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
Date added: 2017-03-30T17:02:15.818Z

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
Date added: 2017-03-30T17:03:38.844Z

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
Date added: 2017-03-30T17:06:41.78Z

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
Date added: 2017-03-29T17:30:37.599Z

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
Date added: 2017-03-30T17:12:26.475Z

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
Date added: 2017-03-30T16:57:45.446Z

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
Date added: 2017-03-30T17:02:39.587Z

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
Date added: 2017-03-30T17:03:40.062Z

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
Date added: 2017-04-10T22:13:27.595Z

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
Date added: 2017-04-11T21:14:01.171Z

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
Date added: 2017-03-29T17:31:17.154Z

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
Date added: 2017-03-30T17:06:34.577Z

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
Date added: 2017-03-30T17:07:53.19Z

Title: An examination of genetic variation and disease spread in Inonotus tomentosus in the sub-boreal spruce zone of British Columbia.
Contributors: Susan Gibson (author), Kathy Lewis (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Inonotus tomentosus (Fr) Teng. is a fungal pathogen of commercially valuable tree species in British Columbia and one of the most important biotic disturbance agents in sub-boreal and boreal forests in Canada. This study investigated the population variation in six spruce stands infected with Tomentosus Root Rot (TRR) in order to determine whether infection is due to spread by root contact, by basidiospores, or a combination of the two and if forest management affects the mode of disease spread. Three marker types were used to test for variation in populations. These included vegetative compatibility (VC), random amplified polymorphic DNA (RAPDs) and single strand conformation polymorphisms (SSCP). Genetic and genotypic variation as well as linkage disequilibrium and random mating were measured. There is high genotypic variation within all populations in addition to moderate levels of gene diversity, significant linkage disequilibrium and significant deviation from Hardy- Weinberg Equilibrium. Analysis of Molecular Variance (AMOVA) indicated that 70% of genetic variation occurred within populations and 28% occurred between populations. This indicates that some clonal propagation is occurring in these populations but frequent recombination (i.e. sexual reproduction) and subsequent spore dispersal (although spatially limited) is the most likely cause of the high level of genotypic diversity observed in these sites. There was no apparent difference in the population structure of this pathogen between unmanaged mixed-species stands and spruce plantations. Given this information, the current management guidelines for treating sites affected by TRR may be insufficient because many of them are aimed at interfering with spread by root contacts.
Discipline: Biology
Date added: 2017-03-30T16:59:49.397Z

Title: Using bioclimatic envelope modelling to incorporate spatial and temporal dynamics of climate change into conservation planning.
Contributors: Nancy-Anne Rose (author), Philip Burton (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Current and predicted trends in climate are diverging from historic norms, thereby compromising the equilibrial basis of our resource management frameworks. This study investigates the impacts of climate change on biodiversity in the context of conservation planning for British Columbia's Central Interior. I used bioclimatic envelope modeling and a climate interpolation and general circulation model downscaling tool to assess 73 rare plant species, 103 biogeoclimatic variants, and 30 terrestrial ecosystem units. I mapped areas projected to support climate suitable for the persistence of those conservation targets through to the 2080s. Results illustrate the potential for disruptive change only 12% (24) of the 206 targets are projected to experience persistent climate at their current locations. Although strong overlap among locations projected to persist for different targets was not found, and those areas meeting multiple objectives (including value independent of climate change) are clear priorities for protection. This methodology can function as a valuable tool for conservation planners and resource managers. --P. [i]
Discipline: Biology
Date added: 2017-03-30T17:07:38.621Z

Title: Spore dispersal and infection of lodgepole pine by Dothistroma septosporum in northwest British Columbia.
Contributors: Kennedy Boateng (author), Kathy Lewis (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Spore dispersal and infection by Dothistroma septosporum which has severely attacked lodgepole pine plantations in northwest British Columbia were studied. Spore abundance was assessed at different distances and heights from single juvenile tree inoculum sources and microclimatic factors were recorded during two consecutive years. One- year-old lodgepole pine seedlings were exposed to natural conditions at the study sites for inoculation. Conidia were assessed from spore traps from June to September in 2009 and were present in the samples whenever rain fell, with a peak in July. It was rare to detect spores more than 2 m away from inoculum sources. The timing and number of conidia dispersed were strongly tied to the climatic variables, particularly rainfall. Infection of the seedlings by the fungus was strongly influenced by the exposure periods, number of spores and high relative humidity. The results suggest increasing the planting distances between susceptible tree species through mixed species plantations and promoting dry conditions within pine plantations may be valuable strategies to reduce the spread of the disease and manage lodgepole pine plantations in the area. --P. ii.
Discipline: Biology
Date added: 2017-03-30T17:09:16.454Z

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