Life Sciences Commons^™

Variation In Mainland Northwest Territories Late-Winter Muskox (Ovibos Moschatus) Density Estimations And Habitat Associations Above And Below Treeline., Charlotte Rentmeister

Theses and Dissertations (Comprehensive)

The Arctic and Sub-Arctic ecosystems are seeing accelerated changes in temperature, landcover, and consequently species abundance and distributions. Reliable distributions, and associated population density estimates, are essential for effective conservation and management efforts. Growing concerns from northern communities regarding the relationship between muskox and declining caribou populations strengthens the need for updated information on muskox populations within mainland Northwest Territories (NWT). The first objective for my research was to quantify and map updated winter estimates of abundance, density, and distribution of muskoxen within three recent survey regions located in mainland NWT, using a multiple covariate distance sampling method (MCDS), paired …

Potential Effects Of Road Proximity On Zooplankton Communities And Water Quality In Lakes In The Northwest Territories, Marie N. Hannan

Theses and Dissertations (Comprehensive)

Studies conducted along Canada’s Dempster Highway in the Northwest Territories have shown that road dust can affect water quality in roadside lakes, leading to higher calcium, conductivity, and pH levels. These water quality changes have the potential to affect important members of the lower aquatic food web, such as zooplankton.

For my thesis research, I had two main objectives: 1) To determine if changes in water chemistry caused by deposition of road dust affects zooplankton communities; and 2) To examine if the type of roadside vegetation influences the effects of road dust on aquatic habitats. To achieve these objectives, I …

Investigating The Effects Of Disturbance And Competition On Establishment, Growth, And Reproduction Of The Endangered Ripariosida Hermaphrodita, Daniel Engelking

Theses and Dissertations (Comprehensive)

Ripariosida hermaphrodita (Virginia Mallow) is a perennial riparian plant with broad, maple-like leaves. It grows up to three meters high and is often found in large clonal patches, but sexually reproduces readily. While this plant may seem like a redoubtable competitor when growing in large colonies, it is declining across its range in North America. The only known occurrences in Canada are in southern Ontario. Prior to this study, no new populations had been recorded even though one of the known populations produces copious amounts of viable seed with potential to disperse. There are many hypotheses for its rarity, but …

Discerning Friend From Foe: Systematic Revision Of Cuscuta L. Section Indecorae Using A Combined Ecological, Morphometric, And Phylogenetic Approach., Corey Burt

Theses and Dissertations (Comprehensive)

The genus Cuscuta (Dodder; Convolvulaceae) are obligate parasitic plants. In one clade known as section Indecorae, there are species which are considered pests that pose significant threats to agricultural crop production, while other species are rare or known only from historical records. Section Indecorae contains three species: C. coryli, C. warneri, and C. indecora (the latter with three infraspecific taxa: var. indecora, var. longisepala, and var. attenuata). The systematics of section Indecorae are not currently resolved. Cuscuta indecora has a long and complicated taxonomic history with many infraspecific varieties described, and …

Differences In Drifting Invertebrate Communities Across Arctic Ecozones And The Influence On Potential Growth Of Grayling (Thymallus Arcticus), Charles Chanyi

Theses and Dissertations (Comprehensive)

Invertebrate drift is a key process that potentially affects multiple levels of food web organization within stream environments. However, our understanding of the mechanistic drivers of drift in high latitude streams and subsequent bottom-up control that drift may have on fish predators in these environments remains understudied. This project aimed to gain the baseline knowledge of how drift functions across two major high latitude ecozones, the boreal forest and tundra, and how those possible differences in drifting community characteristics may impact drift-feeding Arctic grayling (Thymallus arcticus). These objectives were accomplished by characterizing stream environments across both ecozones, sampling …

Impact Of Orthophosphate As A Corrosion Inhibitor And Chloramine Disinfectant On Drinking Water Biofilm Communities, Mitchell Cooke

Theses and Dissertations (Comprehensive)

A drinking water distribution system (DWDS) must maintain conditions within quality standards which assure the effective and safe transport of finished drinking water from treatment plants to the household tap. Although safe to drink, finished water is not sterile, and may contain hundreds of microorganisms in a single milliliter. These microorganisms are present from the source waters, such as lakes, rivers and aquifers, and have passed through early treatment steps. Final treatment steps, such as the maintenance of disinfectant residuals, are used to further minimize viable cells present and focus on the reduction of harmful organisms. Microbial cells entering the …

Impacts Of Changing Permafrost Conditions On Vegetation Productivity In The Northern Boreal Forest, Emily Ogden

Theses and Dissertations (Comprehensive)

Vegetation productivity across the boreal forest has increased over the past several decades. However, at a regional scale there is large variation from increased (greening) to decreased (browning) productivity and large areas with no measured change. Some of this variation can be explained by disturbances, such as wildfire, or by increased climate variability. In northern regions underlain by permafrost, the interactions between climate, disturbance, and vegetation productivity may be more complex. For my thesis, I used a time-series of ground thermal data from permafrost monitoring sites established by the Geological Survey of Canada along a latitudinal transect of the Northwest …

Changes In Plant Community Composition, Structure, And Function In Response To Permafrost Thaw, Katherine Standen

Theses and Dissertations (Comprehensive)

Air temperature is increasing at three or more times the global average in high latitudes, causing widespread permafrost thaw across the boreal biome. Since the boreal biome stores 30-40% of global terrestrial carbon (C), of which about 30-45% is found in permafrost soils, this temperature increase could cause a large efflux of C to the atmosphere. Climate warming and permafrost thaw are also expected to alter plant community composition and productivity and, given the link between plant functional traits and ecosystem C fluxes, may alter overall ecosystem function. Across the boreal biome of western Canada, we know surprisingly little about …

Arctic Stream Characteristics And Diet Analysis Choice Impact Condition And Diet Estimates Of Ninespine Stickleback (Pungitius Pungitius), Adam Kuhrt

Theses and Dissertations (Comprehensive)

Ninespine stickleback (Pungitius pungitius) are ubiquitous in circumpolar freshwaters, but their ecological role is not well understood. Little research has been conducted on the influence of environmental variables on ninespine stickleback in stream environments, and while they are understood to be generalist feeders, their diet in stream environments is equally understudied. Determining diet is difficult due to biases inherent in all standard diet analysis methods. Morphological gut-content analysis (M-GCA), DNA metabarcoding of gut contents (D-GCA), and stable isotope analysis (SIA) are currently three of the most frequently conducted diet analyses; and while combinations of these methods are commonly …

Design And Validation Of Artificial Feeders To Study Feeding Preferences And Growth Of Hematophagous Juvenile Sea Lamprey (Petromyzon Marinus), Gracie Li-Ting-Wai

Theses and Dissertations (Comprehensive)

The parasitic and invasive land-locked sea lamprey Petromyzon marinus populations contributed to the collapse of the Great Lakes fisheries in the mid-1900s, while native anadromous populations are currently under threat and require conservation efforts for protection. Despite the increasing concern for both populations of this species, the juvenile stage of the sea lamprey’s life cycle has not been well studied. This is due, in part, to ethical concerns raised around holding live host fish with juveniles and the lack of an alternative feeding method to maintain these juveniles in the laboratory. The feeder should be designed to minimize fouling of …

Breaking The Chain – The Role Of Intersexual Genetic Correlations In Sexual Dimorphism And The Consequences And Limits Of Their Evolution, Matthew Ma Maoloni, Tara Newman, Tristan Af Long Dr.

Theses and Dissertations (Comprehensive)

In many sexually reproducing species, males and females often differ in countless ways beyond their primary sexual organs. This phenomenon is known as sexual dimorphism, and it is generally considered to be an adaptive response to differences in the selection pressures experienced by males and females. Despite the advantages associated with sexual dimorphism, it does not evolve completely unhindered – there are plenty of biological effects that can limit the extent and rate of divergence between the sexes. This research project focusses on the potential role of the intersexual genetic correlation (r_mf­) – which describes the …

Drivers And Consequences Of Alnus Alnobetula (Green Alder) Distribution At The Taiga-Tundra Ecotone Of The Northwest Territories, Cory Wallace

Theses and Dissertations (Comprehensive)

Climate warming in the Arctic is occurring considerably faster than the global average. One of the most widespread biological responses to this warming in terrestrial systems has been a marked increase in the productivity of shrubby vegetation. Increased shrub growth and reproduction has the potential to alter both local and global aspects of ecosystem function, making understanding its drivers and environmental impact an important research priority. In this context, considerable research has focused on characterizing relationships between shrub cover, abiotic conditions, and understory communities. However, fewer studies have co-located measurements of these components simultaneously in undisturbed tundra shrub patches to …

Rockhounding, Seafaring, And Other Material Tales For The End Of The World, Noemie Fortin

The Goose

In the face of accelerated environmental degradation and climate instability, the future of the Earth and of all life on earth is difficult to visualize. Therefore, the different mediums through which we consider environmental issues are just as important as the actions we take to address them. Focusing on three projects combining art, science, and activism, this article suggests a compilation of material tales. They tell stories of plastic rocks and aluminum nuggets where the protagonists are partly finely crafted objects, partly waste materials, and sometimes both at once. Artists Kelly Jazvac, Yesenia Thibeault-Picazo, and the collective Studio Swine collaborate …

Impacts Of Transportation Infrastructure On Water Quality, Sediment Loads, And Fishing Opportunities In The Gwich’In Settlement Area, Northwest Territories, Matthew Teillet

Theses and Dissertations (Comprehensive)

The addition of gravel sediment to build ferry landings on the Peel and Mackenzie Rivers has been an ongoing concern for the Gwich’in communities of Fort McPherson and Tsiigehtchic that depend on the rivers for their livelihoods. Specifically, there are concerns that gravel from ferry landings is degrading water quality, harming fishing opportunities, and altering river morphology downstream. Previous reports concluded that ferry operations were not impacting downstream ecology. However, past studies had methodological shortcomings and community concerns about the ferry landings remain. To study the impact of the gravel landings on water quality, I utilized a multidisciplinary study design …

Can Zooplankton On The North American Great Plains ‘Keep Up’ With Climate-Driven Salinity Change?, Mariam Elmarsafy

Theses and Dissertations (Comprehensive)

The Great Plains of North America are projected to become more arid as the climate changes over the next century. Salinity levels for lakes in this region are linked to climate, suggesting that lakes will become more saline as the climate becomes drier. One group of organisms that might be affected by increased salinity levels are the zooplankton, aquatic invertebrates that transfer energy from primary producers to macroinvertebrates and fish. Little is known about the ability of zooplankton to adapt to long-term increases in lake salinity levels. For my thesis, I used resurrection ecology to examine how a common zooplankter, …

Abiotic Conditions, Algal Biomass & Fish Growth Rates Affect Fish Mercury Concentrations In Two Subarctic Lakes, Ari Yamaguchi

Theses and Dissertations (Comprehensive)

Kakisa Lake and Tathlina Lake, located in the Dehcho Region of the Northwest Territories, support important fisheries for the local Ka’a’gee Tu First Nation (KTFN). Recently, Walleye (Sander vitreus) of typical catch size in Tathlina Lake were found to have mercury concentrations above Health Canada’s commercial sale guideline of 0.5 ppm. Wild foods with elevated mercury concentrations can pose health risks to the humans who consume them, depending on consumption amounts and vulnerability factors such as age and pregnancy. Because wild fish can accumulate relatively high mercury levels and subsistence fishing contributes greatly to food security in northern …

Does A Carbonatite Deposit Influence Its Surrounding Ecosystem?, James M.C. Jones, Elizabeth A. Webb, Michael D.J. Lynch, Trevor C. Charles, Pedro M. Antunes, Frédérique C. Guinel

Biology Faculty Publications

Carbonatites are unusual alkaline rocks with diverse compositions. Although previous work has characterized the effects these rocks have on soils and plants, little is known about their impacts on local ecosystems. Using a deposit within the Great Lakes–St. Lawrence forest in northern Ontario, Canada, we investigated the effect of a carbonatite on soil chemistry and on the structure of plant and soil microbial communities. This was done using a vegetation survey conducted above and around the deposit, with corresponding soil samples collected for determining soil nutrient composition and for assessing microbial community structure using 16S/ITS Illumina Mi-Seq sequencing. In some …

Arts Of Living On A Damaged Planet: Ghosts And Monsters Of The Anthropocene By Anna Lowenhaupt Tsing, Heather Anne Swanson, Elaine Gan, And Nils Bubandt, Randy Lee Cutler

The Goose

Review of Anna Lowenhaupt Tsing, Heather Anne Swanson, Elaine Gan, and Nils Bubandt's Arts of Living on a Damaged Planet: Ghosts and Monsters of the Anthropocene.

Hawk On Wire: Ecopoems By Scott T. Starbuck, Vivian M. Hansen

The Goose

Review of Scott T. Starbuck’s Hawk on Wire: Ecopoems

Ecological Art: Art With A Purpose, Aaron M. Ellison, David Buckley Borden

The Goose

Ecological art is purposeful and often prescriptive: the actions and directions intended by the artists for activists to undertake often are clearly represented. Yet, ecological art has been no more successful than, for example, targeted scientific research, deposits on returnable bottles, or land-protection campaigns at slowing global warming, reducing the amount of waste we generate every day, or halting the ongoing sixth mass extinction in the history of the Earth. Here, we consider the idea that prescriptive ecological art provides insufficient mental space for creative reflection about future scenarios of, and responses to, environmental change. We ask whether, by presenting …

Competition Or Facilitation: Examination Of Interactions Between Endangered Sida Hermaphrodita And Invasive Phragmites Australis, Samantha N. Mulholland

Theses and Dissertations (Comprehensive)

Virginia Mallow (Sida hermaphrodita) is a perennial herb of the Malvaceae family that is native to riparian habitats in northeastern North America. Throughout most of its geographical distribution however, it is considered threatened and only two populations are known from Canada. The biology and ecology of S. hermaphrodita are still poorly understood and although few studies have been performed to determine the factors that contribute to the species rarity, it is considered threatened potentially due to the loss of habitat caused by exotic European Common reed (Phragmites australis subsp. australis) invasion. Allelopathic and phytotoxic conditioning of …

Happy Or Hangry Families: Does Kinship Mediate Cooperation And Cannibalism In Drosophila Melanogaster Larvae?, Lucas Khodaei

Theses and Dissertations (Comprehensive)

The fruit fly Drosophila melanogaster has a long history as a research model for studies on behaviour and group dynamics. When individuals are grouped in an environment and resources decrease, then they may behave co-operatively with one another or antagonistically compete. Hamilton’s Law states that if the benefit of helping a related individual out-weighs the cost to its direct fitness, then the individual’s indirect fitness will increase when they help their kin compared to helping an unrelated stranger. Yet it is unknown whether kinship mediates larval behaviour to encourage co-operation and/or lessen antagonistic behaviours between consanguineous individuals. In this thesis …

Factors Influencing Zooplankton Communities In Small Arctic Lakes, Northwest Territories, Jasmina Vucic

Theses and Dissertations (Comprehensive)

The Canadian Arctic has been warming at an unprecedented rate, causing significant changes to the environment. At the same time, continued development in the north has increased the demand for gravel extraction used to construct and maintain infrastructure such as highways. The development of roadways and gradual loss of permafrost in Canada’s north has led to changes in water quality, including increased calcium, conductivity, and nutrients. In addition, gravel extraction has led to the formation of artificial gravel pit lakes. Research has yet to determine how physical and chemical changes associated with development and permafrost thaw might impact zooplankton, and …

Environmental Factors Associated With Benthic Macroinvertebrate Communities In Arctic Lakes, Northwest Territories, Rachel Cohen

Theses and Dissertations (Comprehensive)

Lake water quality and the macroinvertebrate communities in Arctic regions are threatened by increased development and climate change. In order to understand how macroinvertebrate communities may respond to their changing environment, I performed a biological and water quality survey of 46 Arctic lakes located in the Gwich’in Settlement Area and the Inuvialuit Settlement Region of the Northwest Territories. Using these survey data, I performed two interrelated studies that asked: 1) how artificial pit lakes associated with gravel extraction for road development compared with natural lakes in terms of their water quality, morphometry, and macroinvertebrate communities; and 2) how water quality …

Yardwork: A Biography Of An Urban Place By Daniel Coleman, Vivian M. Hansen

The Goose

Review of Daniel Coleman's Yardwork: A Biography of an Urban Place.

Mourning Nature: Hope At The Heart Of Ecological Loss And Grief By Ashlee Cunsolo And Karen Landman, Jenna Gersie

The Goose

Review of Ashlee Cunsolo and Karen Landman's Mourning Nature: Hope at the Heart of Ecological Loss and Grief.

Perma/Culture: Imagining Alternatives In An Age Of Crisis By Molly Wallace And David Carruthers, Bryant Scott

The Goose

Review of Molly Wallace and David Carruthers' Perma/Culture: Imagining Alternatives in an Age of Crisis.

Rain Shadow By Nicholas Bradley And Cloud Physics By Karen Enns, Kelly Shepherd

The Goose

Review of Nicholas Bradley's Rain Shadow and Karen Enns' Cloud Physics.

The Wasteland, Tiasa Adhya

The Goose

Riverine floodplains and deltas that have cradled human civilization and are now ravaged by ecologically blind land-use policies form the context of this poem. Policies that term nutrient rich wetlands as "wastelands" are economically motivated and backed by policy makers for short-term gains. The conversion of wetlands makes refugees out of resident wild species. The first few lines of the poem describe the character of the fishing cat, the only cat in South Asia that is adapted for wetlands and is an indicator of the health of wetland ecosystems. The poem talks of a nemesis that awaits the human world—we …

The Wolf Is Back By Robert Priest, Kelly Shepherd

The Goose

Review of Robert Priest's The Wolf is Back.