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Tsattine People and Bison: Pre-Colonial Relationships and Ancestral Territories
Get PDFTraditional knowledge and historical records indicate that communal hunting was an
important practice for subarctic Beaver people (Dunne-zaa / Dane-zaa / Tsattine) of northern
Alberta and northeastern British Columbia. Prior to the 20th century Beaver people hunted a
variety of animals, including American bison (plains bison [Bison bison bison] and wood bison
[Bison bison athabascae]), which were nearly eradicated in North America by the late 1800s due
to colonial impacts associated with European settlement. My thesis explores traditional
relationships Beaver people had with animals, possible Beaver communal hunting methods and
locations, and the subarctic/northern plains range of bison. I explore the social relationships
between Beaver people and animals through stories, ethnographic and historical records. I argue
that acknowledging this social relationship with animals supports revitalization efforts by
challenging Western standpoints that often view animals (particularly food animals) as non-sentient beings, which is in contrast to Beaver/Indigenous understandings of animals as persons.
I describe five potential communal hunting sites that may have been utilized by Beaver people
for bison drives and/or jumps. Oral accounts of bison jumps in these northern regions contradicts
Western literature which suggest that jumps did not occur in these areas, so further examination
of these sites is recommended. [...
Population genetics of caribou in the Brightsand range of Ontario
Get PDFBoreal woodland caribou are listed as threatened in Ontario. This thesis examined whether the genetic diversity of boreal woodland caribou in the Brightsand Range differs comparing populations in portions of the range with contrasting levels of disturbance. The GenAlex software was used to run three Analysis of Molecular Variances that showed that there was no significant difference in allele frequencies of the populations of caribou in the Brightsand range, but that the genetic diversity was lower in southern populations with more cutting of trees and road access causing fragmentation of the habitat. The lack of difference may be due to gene flow that is high enough to prevent loss of genetic diversity in the southern portion of the range
Effects of road construction cost in determining whether a block should be harvested in the summer or winter on the Romeo Malette Forest
Get PDFPermanent and temporary forest roads are key infrastructures for the removal of raw
forest products. Ensuring an efficient road network is laid out and proper construction
methods are chosen will aid in reducing the total cost. Winter roads tend to be found
on lower elevated blocks where there tends to be lower volumes. Summer roads are
constructed on higher terrain or higher volume blocks. Green First and Debastos and
Sons provided data and maps to undergo a cost comparison on three blocks. Three
scenarios were used to determine the most optimal road network that will ensure the
transportation costs will be economical. Summer roads were determined to be the
more suitable construction method for blocks 417 and 449. Gravel aids in increasing
the bearing capacity of the roads but can become costly if the haul is too far. Block 532
is located in lower terrain where a winter road network was recommended as the
block contains low volume. We concluded that lower elevated blocks with summer
road networks would cost too much. The low volume and wetlands increase the costs
significantly as the construction process will require more work. This study determines
an optimal road network for each block and provides cost comparison of each scenario
The effects of climate change on the growth and spawning phenology of fishes in aquatic boreal environments
Get PDFGlobal climate change is occurring and observed warming patterns have had significant
impacts on aquatic environments as trends in water temperature are closely related to trends in
air temperature. In ectothermic organisms such as fishes, temperature is relevant to the
maturation and deposition of gametes during spawning, and lifetime growth potential. By using
historical spawning and size at age datasets spanning 43 years, I estimated more than 100 peak
spawning dates for White Sucker (Catostomus commersonii) and Lake Trout (Salvelinus
namaycush) and described changes in growth of White Sucker to summarize the observed effects
that local climate warming over the past 50 years has had on two economically and culturally
important fishes in Northwestern Ontario. I show how spawning events are dependent on annual
variation in seasonal thermal conditions, and how long-term increases in average fall surface
water temperatures by 1.4oC and decreases to thermal cooling by 87
oCᐧdays in lakes have shifted
the peak spawning date of Lake Trout by 5 days over the past 4 decades. Additionally, I show
how changes in population density, likely as a result from increased survival and recruitment of
juvenile White Suckers have worked to dramatically reduce the body size of White Sucker by
over 90% in weight and 50% in length in some populations. Finally, I discovered that declining
White Sucker body size appears to be a common pattern across an expansive geographic range.
These results fill knowledge gaps in the current literature by providing observational accounts of
climatic impacts to inland fish populations for a highly studied culturally significant species, and
for a lesser considered, but ecologically important species
Attitude control of a quadrotor UAV: experimental implementation
Get PDFUnmanned aerial vehicles (UAVs) are becoming ubiquitous due to their potential benefits
in many civilian and military applications. UAVs are designed to accomplish complex
tasks safely and effectively, such as search and rescue missions, package delivery, building
inspections, film making...etc. The attitude controller is one of the most important and
fundamental components that allows the UAV to balance itself in the air.
In this thesis, a PX4-based quadrotor experimental platform has been built and used to test
the attitude control algorithms. MATLAB/Simulink R2021a with the UAV Toolbox Support
Package for PX4 Autopilots is used to program the control algorithms. A nonlinear attitude
estimator and three PID-type attitude controllers have been successfully implemented on
the quadrotor.
A discussion about the performance of the obtained experimental results for the three
different attitude control schemes is provided
New insights into modern human behaviour at Liang Bua (Flores, Indonesia) based on the temporal distribution of pottery and mollusks during the past 5,000 Years
Get PDFIn addition to preserving a rich archaeological record spanning from ~190 thousand years
ago (ka) until the terminal Pleistocene, Liang Bua (Flores, Indonesia) also preserves a rich and
relatively complete Holocene stratigraphic sequence with dense accumulations of faunal
remains, stone artifacts, and pottery. In this study, the abundances of pottery sherds and various
mollusk taxa were examined across nine stratigraphic units to explore temporal variation during
the past 5,000 years. This temporal period is important because it is during this time that human
populations living in this area shifted from a foraging to a sedentary, agricultural lifestyle. Using
data obtained from new archaeological excavations at the site, the first aim of this study was to
improve knowledge of when pottery was first introduced as previous research has suggested that
this occurred either ~4 ka or ~3 ka. The second aim of this study was to increase understanding
about the mollusk assemblage at Liang Bua in terms of its temporal range and taxonomic
composition. Particular emphasis was placed on determining whether humans were responsible
for accumulating all or part of this large assemblage, which included 3,515 three-dimensionally-
plotted specimens and 4,270 specimens recovered from sieved sediments.
The results show that pottery was most likely first introduced to the site ~3.3 ka and used
regularly after ~3 ka, likely signaling a shift to increased sedentism or farming in this area. The
main shell midden at Liang Bua was deposited between ~4.4 and 3.3 ka and includes mostly
freshwater species. Interestingly, 63.1% of Tarebia granifera and 66.7% of Melanoides
tuberculata recovered in Sectors XXXII-XXIX showed signs that they were deliberately cut at
their apices. Deliberately cutting the apex of a shell is almost certainly a strategy to obtain the
meat of the clam for human consumption. Furthermore, the presence of 12 culturally modified
marine shells at Liang Bua suggests that, after ~4.4–4.3 ka, past peoples living around Liang Bua
had strong social and/or symbolic connections to coastal areas either through their own foraging
ranges or through trade networks with other peoples living nearer to the ocean
Effects of a second wood ash application to soil on Picea mariana (Mill.) B.S.P. and Picea glauca (Moench) voss growth and foliar nutrition and soil chemistry
Get PDFAs the Canadian biomass energy sector grows, so too does its production of by-products
such as wood ash from the combustion of wood biomass for energy. Wood ash can be land applied with
the goal of increasing the productivity of a site through an increase in soil pH and available
nutrients. Most studies have focused on a single ash application to the soil. The purpose of this
study is to investigate the effects of re-applying wood ash on the chemistry of a forest soil and
the growth and foliar nutrition of two commercially important tree species (Picea mariana (Mill.)
B.S.P. and Picea glauca (Moench) Voss). A low and high carbon wood ash sourced from vibrating power
boilers at the Resolute Forest Products facility in Thunder Bay were re-applied in 2019 to plots
established in 2012 at the Ministry of Natural Resources, Northwest Science and Technology Center,
25th Side Road. The wood ashes were applied at 0, 1000, and 10 000 kg ha-1 alone and in combination
in 5 replicate blocks. Tree height and diameter were measured in the Fall of 2019 and 2020 and soil
and foliar samples were collected at the same time for chemical analyses. A second application
significantly affected concentrations of soil C, C:N, conductivity, pH, total soil Ca, S, Sr, and
exchangeable Ca, K, Mg, Na, and extractable Cu, Mn, and Zn concentrations. Differences attributable
to species were observed for soil C concentrations, conductivity and exchangeable K concentrations.
Concentrations of soil C, conductivity, exchangeable K and extractable Zn differed between years.
Three trends were observed in soil chemistry: 1) low C ash had a greater effect on measured
parameters than the high C ash, 2) applying ash at higher rates had a greater effect, and 3)
applying low C ash in addition to high C ash had greater impact on soil than when high C ash was
applied alone. Foliar and growth response from wood ash re-application were species dependant.
Picea marianna (black spruce) showed a negative foliar Mn response and a non-significant but
negative height growth response to ash where Picea glauca (white spruce) did not show any effect of
ash application. Lower foliar Al and black spruce foliar Mn were observed when higher amounts of
ash were applied and when low C ash was applied. Foliar S responded to ash application after the
first growing season and low C ash had the greatest effect. Comparing these results to the first
ash application in 2012: 1) high C ash had a greater impact on soil chemistry after the second ash
application, 2) the concentration of some soil metals (extractable Cu, Zn, and Mn, and total Sr and
Ca) increased with the second application, though not to toxic concentrations. This study shows
that a repeat ash application to soils can increase concentrations of Ca, K, Mg, and S in soil,
reduce the impact of soil acidification, and combat soil C depletion that follows whole tree
harvesting, at least in the short term, while having no significant immediate negative effects on
black and
white spruce growth and foliar nutrition
Invasive spiny water flea (Bythotrephes cederströmii) and their impacts on young-of-year walleye (Sander vitreus) growth
Get PDFInvasive species are a major threat to aquatic ecosystems, costing an estimated $3.6
billion in impacts across Ontario. In particular, the predatory cladoceran Bythotrephes
cederströmii (Bythotrephes hereafter) has had significant trophic impacts on invaded
ecosystems, such as decreasing zooplankton density and biomass. Changes to the
zooplankton community can impact ecosystem energy rates and dominant pathways of
transfer to other organisms in a “middle-out” trophic cascade, altering predator-prey
dynamics for both algae and fish. Here, I used relevant zooplankton abundances
characteristic of invaded and non-invaded lakes and a bioenergetics model to evaluate
whether the Bythotrephes-induced changes to native zooplankton is expected to alter
larval walleye consumption (and therefore rates of growth). I then used observational
data to evaluate the impact Bythotrephes has on the zooplanktivorous young-of-year
(YOY) walleye. I used a back-calculation model and linear mixed effect modeling to
evaluate differences in YOY walleye growth between invaded and non-invaded
waterbodies, as well as within invaded waterbodies pre- and post-invasion. In the first
data chapter (chapter 2), a functional response and bioenergetics model revealed larval
walleye grow slower in invaded mesotrophic lakes compared to non-invaded mesotrophic
lakes, and models suggest they are unlikely to survive in invaded oligotrophic lakes based
on available zooplankton. In the second data chapter (chapter 3), I found that relative to
similar sized non-invaded lakes, YOY walleye grow slower in small, invaded lakes,
whereas large lakes show less severe effects. Overall, Bythotrephes has differing impacts
on YOY walleye growth depending on lake characteristics such as lake size and trophic
state. As growth rates are ultimately linked to reproduction, recruitment, and production, understanding growth rates post-invasion is essential for fisheries managers to develop
and anticipate adaptive management strategies
Interactive effects of elevated CO2 and temperature, nutrition, and ectomycorrhizas on morphological traits and summer shoot formation in jack pine
Get PDFUnderstanding the responses of trees, ectomycorrhizal fungi (ECM) and their association to
climate change can be challenging due to their interactions with multiple environmental factors.
The combined impacts of elevated CO2 and elevated temperature on tree growth are mostly
positive, but the impacts to ECM are less well understood. The objective of this study was to
investigate how the elevations of CO2 and temperature and soil nutrient supply interactively
affect the formation and growth-enhancing efficiency of ECM, as well as the formation of
summer shoots and morphology of jack pine seedlings. One-year old jack pine seedlings were
exposed to ambient CO2 and temperature treatment (ACT: 410µmol/mol CO2 and current
average temperature) and elevated CO2 and temperature (ECT: 750µmol/mol CO2 and current
+6°C temperature) as a single treatment, two nutrient levels (low nutrient LN vs. very low
nutrient VLN) and with or without Hebeloma longicaudum (Pers.)P.Kumm (yes ECM or no
ECM) inoculation. The ECT treatment increased total seedling biomass, root biomass and root
collar diameter (RCD), and most summer shoot formation and growth attributes. The VLN
treatment reduced all growth attributes except for height increment, and height increment +
lammas shoot length. An interactive effect of the CT and N treatment was observed for the RCD,
suggesting that lower nutrient sites may limit the positive affects of elevated CO2 and
temperature on tree growth, and the interactive effect on specific leaf area (SLA) suggests that
the lower nutrients limited the needles’ ability to accumulate carbon at ECT. Another interactive
effect observed on SLA suggests that ECM inoculation allowed for better nutrient uptake and
caused seedlings to demonstrate a higher SLA at VLN under ECT. Both ECT and LN increased
the probability of summer shoot formation. The results suggest that jack pine is less likely to
produce summer shoots on nutrient poorer sites, and in current CO2 and temperature growing
conditions. Furthermore, we observed significant two-way and three-way interactions that
suggest the ECT treatment increased the effectiveness of ECM inoculation in forming
mycorrhizae clusters, and reduced the degree of nutrient suppression to mycorrhizal root cluster
formation. The results of this study highlight the importance of incorporating multiple factors
when evaluating tree responses to climate change, particularly in controlled-environment studies
Black bear attacks in Canada and a review of the factors influencing them
Get PDFCanada has experienced numerous black bear attacks over the last several
decades. The purpose of this study is to determine if there is an increase in the number
of black bear attacks in Canada. Data came from various news sources in each province
and the Northwest Territories to gather information about the attacks. The gathered
information was then separated into a variety of tables and examined to gain insight on
the number of attacks, where they occurred, and the age of the victims. There was a
slight increase in the total number of fatal attacks and a larger increase in the number of
nonfatal attacks over the last 31 years. Encounters were interpreted to be from both
predatory and defensive bears