Theses and Dissertations

Fall 2010

Tremblay, Marie Anne

Urbanization is viewed as a major threat to global biodiversity because of its role in the loss and fragmentation of low-lying, productive habitats associated with coastal plains and river valleys. My study examines the effects of urbanization on the movements and distribution of songbirds in

, and isolation from natural features on the distribution of songbirds. In 563 playback trials involving the responses of 2241 birds, I found that the size of the gap in vegetation was the most important determinant of movement across linear features; the likelihood of movement sharply decreasing as

surveys revealed that natural forest stands played a critical role in sustaining regional avian diversity in the study area. Moreover, functional distance to the nearest forested natural area or water body often explained more variation in the probability of occurrence of focal species than straight-line

Fall 2015

Moreira, Dario A.

significantly affected by native forest, road density and the presence of dogs (Canis familiaris). The magnitude of these effects were also influenced by the time of day and spatial scale. The positive effect of native forest on occupancy probability was stronger during the night for the Darwin's fox

Mammalian carnivores inhabiting human-dominated landscapes may face reduced and heterogeneous distributions of feeding resources while being more exposed to humans and introduced carnivores. Therefore, sustainable landscape planning intended to conserve carnivores in human-dominated landscapes

requires the use of a multi-dimensional approach that integrates different conceptual and methodological components, such as: 1) habitat and prey selection patterns of carnivores at different spatio-temporal scales; 2) habitat selection models including fine-grain information of habitat structure; and 3

Spring 2017

Hunt, Anjolene R

found that use of post-harvest stands did not affect probability of pairing or fledging young, but that pairing success was lower when male densities were high. My final objective was to discuss potential reasons for discrepancies between conclusions about the effects of forestry on Canada Warblers

Recovery strategies for species at risk are legally mandated in Canada and the Government of Canada must identify which habitat is important for a species and which activities result in its destruction. The Canada Warbler (Cardellina canadensis) has been designated as a threatened species in Canada

due to large population declines (~3% annually over the last 50 years). Forestry has been identified as a threat, but some studies suggest it can create productive breeding habitat. I quantified multiple orders of habitat use to study the response of the Canada Warbler to forestry, accounted for the

Fall 2021

Pentyliuk, Natasha

on biological sampling, and for every report of Prussian carp received in a HUC-8 area (hydrological unit code 8; the second finest Albertan watershed unit), the probability that area was invaded (as indicated by biological sampling) increased by more than 10 times (Chapter 3). We also found a

spread priorities when it comes to addressing the invasion. Accurate distribution information is essential for targeting such efforts but is challenging to obtain given the logistics of continually sampling all locations within Prussian carp’s potential range. Could resource users be used in a citizen

science program to generate species distribution data? Here we investigate whether reports of Prussian carp by recreational anglers in Alberta, Canada could have application as a cost-effective alternative to or complimentary tool for traditional population distribution sampling and early warning systems

Fall 2013

Rajakaruna, Harshana

spread? In this thesis I focus on how seasonal fluctuation of habitat temperature impacts persistence, range expansion and distribution of invasive marine species by developing simple biologically meaningful metrics and producing results consistent with advanced mathematical methods. First, I show how

into account. The major conclusion in this thesis is that annual temperature cycles and their amplitude-gradients across ecoregions may drive species invasion dynamics and diversity distribution. A large potential of the conveyor belt together with the escalated human-mediated propagule flow may

the ambient temperature impacts the net reproductive rate of invasive marine calanoid copepod Pseudodiaptomous marinus, thereby, the invasibility of habitats to P. marinus. I extend this approach to include periodic fluctuations of habitat temperature by defining a new weighted net reproductive rate

Spring 2016

Stralberg, Diana

Often referred to as North America’s bird nursery, the boreal forest biome provides a productive environment for breeding birds, supporting high species diversity and bird numbers. These birds are likely to shift their distributions northward in response to rapid climate change over the next

) model uncertainty in current and future projections, (2) time lags in ecosystem responses to climate change, (3) the static nature of correlative models, and (4) the influence of historical biogeography in determining current distributions. In my first chapter, using a continental-scale avian dataset

younger forest. In my third chapter, I developed a hybrid modelling approach based on topo-edaphically constrained projections of climate-driven vegetation change potential, coupled with weather- and fuel-based simulations of future wildfires, and projections of large-scale industrial development

Fall 2009

Avila-Flores, Rafael

. Although increased isolation may reduce the probability of occurrence at a given site, highly isolated locations may support high population densities. Contrary to my original predictions, I did not detect significant impacts of human-related factors on BTPD distribution and abundance.

decline with the occurrence of most intense drought suggests a prominent role of drought in the population collapse. Overall, patterns of BTPD occurrence and abundance in Chihuahua are greatly influenced by spatial and temporal variation in forage cover. Although BTPDs were more likely to occur in open

areas with short vegetation, increased forage cover positively predicted occurrence. High levels of forage cover during the dry season were positively related with BTPD density, juvenile production and population rate of change, but forage cover during the preceding rainy season was a negative

Fall 2017

Neilson, Eric W

The degree to which predator and prey distributions overlap in space influences the probability of encounters between predator and prey, kills of prey, and consequently, how each species’ abundance varies in time and in space. Predator and prey attempt to increase or decrease overlap respectively

for moose was available due to human disturbance. Further, I found that a higher proportion of moose were killed as the distance to oil sands mines decreased. I also found that wolves selected to move on linear features associated with oil extraction and such selection facilitated faster movement

through movement and habitat selection, processes that are sensitive to habitat heterogeneity. If predator and prey respond differently to novel habitat heterogeneity such as a zone of influence in and around human disturbance, it may provide prey with a refuge or facilitate predator hunting efficiency

Fall 2013

Ball, Jeffrey R

spatial distribution or probability of nest predation by the majority of nest predators was strongly affected by edge proximity. Of all the predators monitored, only bears and deer mice were more common near edges but they depredated few nests. I also did not find strong support for a negative edge

Nest predation is a major source of reproductive failure for many species of songbirds. Habitat fragmentation by human land use creates edge habitat that can alter predator-prey dynamics, create ecological traps, and reduce the amount of high quality habitat available for sustaining bird

effect of linear features on songbird nest fate (n = 571 nests) relative to forest interiors. Ground nest survival was marginally higher near edges and ground and shrub nest survival was marginally higher where squirrels were absent. In contrast, the survival of canopy nests was higher away from the edge

Fall 2016

Sparkes, Shantel N

-1990 and inside the Monument from 2000-2010. We discussed trends in estimates of elk carrying capacity to trends in the elk summer distribution, body condition, probability of pregnancy, and overwinter elk mortality across a portion of the study area and found a general correspondence. Results from

/ha) within a core area of the Mount St. Helens elk population since the 1980 eruption based on digestible energy of preferred forage species using the Forage Resource Evaluation System for Habitat model (FRESH). I constrained estimates of NCC by considering only areas with a minimum amount of

indicated elk selection was most strongly influence by available digestible energy, followed by distance to forage-cover edge, distance to a public road and slope. Constraining the NCC by relative use resulted in 2-49% decrease across study years with the greatest declines on industrial lands from 1980