Environmental and Life Sciences

Introgressive hybridization between northern (Glaucomys sabrinus) and southern flying squirrels (G. volans) has been observed in some areas of Canada and the USA. However, existing molecular markers lack the resolution to discriminate late-generation introgressants and describe the extent to which hybridization influences the Glaucomys gene pool. I report the first North American flying squirrel (genus Glaucomys) functionally annotated de novo transcriptome assembly with a set of 146,621 high-quality, annotated putative species-diagnostic SNP markers. RNA-sequences were obtained from two northern flying squirrels and two southern flying squirrels sampled from Ontario, Canada. I reconstructed 702,228 Glaucomys transcripts using 193,323,120 sequence read-pairs, and captured sequence homologies, protein domains, and gene function classifications. These genomic resources can be used to increase the resolution of molecular techniques used to examine the dynamics of the Glaucomys hybrid zone.

Author Keywords: annotation, de novo transcriptome, flying squirrels, high-throughput sequencing, hybridization, single nucleotide polymorphisms

Wild lupine (Lupinus perennis) restoration efforts seek to increase and connect populations, using seeds, to facilitate the recovery of endangered butterflys in Ontario. This study observed plant growth and phytohormone levels of L. albus, L. polyphyllus, and L. perennis through stages of seed development, each with varying strategies in growth and reproductive investment. L. polyphyllus is similar to L. perennis in morphology, acting as similar comparable with L. albus, a well-studied annual, as an outgroup comparator.

Wild lupines showed a lack of sexual reproductive effort as they did not put as much effort into above ground growth, and few in the population reproduces. They also showed cis-zeatin, a weaker cytokinin, throughout development and had higher amounts of abscisic acid at the end of seed maturity, impacting their ability to develop and germinate. These factors contribute to why wild lupines are difficult to restore using seeds, limiting expansion and challenging restoration.

Author Keywords: L. albus, L. perennis, L. polyphyllus, plant physiology, seed development, Wild blue lupine

Biological differences between island and mainland conspecifics have been well studied, but few studies have addressed differences in stress physiology. Stressors, such as predation and competition for resources, cause the release of glucocorticoids (GCs). Characteristics of island wildlife, called "island syndrome", are attributed to low levels of predators and competitors. I tested the hypothesis that island syndrome includes differences in GC levels between island and mainland rodents using two approaches; first, using white-footed mice (Peromyscus leucopus) from a near-shore archipelago (Thousand Islands, Ontario) and the nearby mainland; second, using study-skins of deer mice (Peromyscus maniculatus) from two archipelagos offshore of Vancouver Island, British Columbia. White-footed mice in the near-shore archipelago did not show characteristics of island syndrome, or changes in GC levels (feces and hair); however deer mice from both archipelagos in British Columbia were heavier and had lower hair GCs for their size than Vancouver Island mice.

Author Keywords: Glucocorticoids, Island rule, Island syndrome, Peromyscus, Stress physiology

Early developmental stages of cold-adapted ectotherms such as brook trout

(Salvelinus fontinalis) are at risk of mortality with increasing water temperatures because

of their sensitivity to changes in their environment. I studied the mass and routine

metabolic rate (RMR) of wild-origin brook trout eggs, alevin and young fry reared at

normal (5°C) and elevated (9°C) temperatures for the duration of the study or at

mismatched temperatures. This setup determined if preconditioning acclimation for one

temperature benefits or hinders the organism later in life. Three levels of biological

organization (ancestry, population, family) were studied using Akaike's Information

Criterion (AIC) to identify models that best accounted for variation in the data. Family,

mass and temperature were most important in predicting body mass and mass-adjusted

RMR, although population and ancestral-level differences were also detected at some life

stages. Strong variation in body mass and mass-adjusted RMR among families may

indicate adaptive potential within brook trout populations to respond to increases in water

temperature with climate change.

Author Keywords: Acclimation, AIC, Brook trout (Salvelinus fontinalis), Environmental matching, Routine metabolic rate, Temperature

Polar bears are generally described as solitary, but features of their life cycles and

habitats regularly necessitate interaction. Effective conspecific assessment, including accurate

recognition and discrimination, likely confers benefits, especially to females accompanied by

dependent young. Individuals in the Southern (SH) and Western (WH) Hudson Bay

subpopulations are ideal for studying polar bear social behaviours because of the prolonged

high densities of the ice-free season. First, I looked outside family groups to model their fine

scale sociospatial organization on land. Capture locations were more likely to correspond to

family groups when there were fewer neighbouring bears, when a greater proportion of

neighbours were female, and when the focal individual and neighbours were significantly

related. Second, I looked within the family group to assess offspring recognition. Of 288

offspring in 207 family groups captured in the SH subpopulation from 1999 through 2013, only

one case of adoption (of a singleton) was observed.

Author Keywords: Adoption, Kin Recognition, Logistic Regression, Maternity Analysis, Social Discrimination, Sociospatial

The purpose of this thesis is to enhance forensic entomology applications through identifications and ecological research with samples collected in collaboration with the OPP and RCMP across Canada. For this, we focus on blow flies (Diptera: Calliphoridae) and present data collected from 2011-2013 from different terrestrial habitats to analyze morphology and species composition. Specifically, these data were used to: 1) enhance and simplify morphological identifications of two commonly caught forensically relevant species; Phormia regina and Protophormia terraenovae, using their frons-width to head-width ratio as an additional identifying feature where we found distinct measurements between species, and 2) to assess habitat specificity for urban and rural landscapes, and the scale of influence on species composition when comparing urban and rural habitats across all locations surveyed where we found an effect of urban habitat on blow fly species composition. These data help refine current forensic entomology applications by adding to the growing knowledge of distinguishing morphological features, and our understanding of habitat use by Canada's blow fly species which may be used by other researchers or forensic practitioners.

Author Keywords: Calliphoridae, Ecology, Forensic Entomology, Forensic Science, Morphology, Urban

The potential release of nanoparticles into aquatic environments is raising global concerns. As antimicrobials, silver nanoparticles (AgNPs) are among the most prominent form in use. Despite this, their fate, long-term toxicity, and ecological relevance have yet to be investigated largely under natural settings with seasonality and environmental complexity. To better understand the environmental significance, we released AgNPs into Lake 222 at the Experimental Lakes Area over two years. AgNPs remained suspended in the water column and were detected throughout the lake and in the lower food web. Total Ag concentrations ranged from below 0.07 to 18.9 μg L-1 in lake water, and were highly dynamic seasonally both in the epilimnion and hypolimnion depending on the physical, chemical and biological conditions of the lake. Approximately 60% of the measured Ag mass in October was present in the sediment in 2014 and 50% in 2015 demonstrating relatively high sedimentation and removal from the water column. During winter months, Ag was largely absent in the water column under the ice. After ice melt and before summer stratification, Ag concentrations increased in the lake suggesting AgNPs may not be tightly bound to the sediment and are able re-enter the water column during spring mixing events. Despite temporal variation, total Ag was highly synchronous across spatial locations for both years, indicating rapid dispersal upon lake entry. When investigating AgNP sizes using spICPMS, size distributions were similar across spatial locations, with the 40-60 nm size class constituting approximately 60% of all particles identified. Large aggregates (>100 nm) and dissolved Ag were infrequently detected within the lake. Ag accumulated in the lower food web ranging from 0.27-16.82 μg Ag mg C-1 in the bacterioplankton and 0.17-6.45 μg Ag mg C-1 in algae (particulate fraction). Partial least squares models revealed the highest predictors of Ag accumulation were dissolved nutrients including DOC, TDN, TDP in bacterioplankton. Major predictors for particulate Ag included temperature, dissolved oxygen, and sampling date. The diversity of predictors among biological compartments emphasizes the importance of understanding the role of environmental complexity within the lower food web. Despite Ag accumulation we did not detect strong negative effects on the lake food web. An increase in particulate and bacterioplankton chlorophyll-a occurred after addition in contrast to reference lakes, which may indicate a hormetic response to low dose AgNP concentrations. Our findings provide the first whole-lake perspective regarding Ag fate and toxicity, suggesting small scale experiments may overestimate environmental

responses.

Author Keywords: Ecotoxicity, Fate, Lower food web, Silver Nanoparticles, Whole-lake addition

Arctic Char (Salvelinus alpinus (L.)) have been, and remain, an important

subsistence resource for the Inuvialuit, the Inuit of the western Canadian Arctic. The effects

of climate variability and change (CVC) in this region have been noticeably increasing over

the past three decades. There are concerns as to how CVC will affect Arctic Char and the

Inuvialuit who rely on this resource as they will have to adapt to changes in the fishery.

Community-based monitoring, is an important tool for managing Arctic Char. Therefore,

my dissertation focused on the central question of: Which community-based monitoring

factors and parameters would provide the information needed by local resources

users and decision-makers to make informed choices for managing Arctic Char

populations in light of CVC?

This question is investigated through an exploratory research approach and a mixed

method research design, using both scientific and social science methods, and quantitative

(scientific ecological knowledge and observation) and qualitative (Inuvialuit knowledge

and observation) information. It is formatted as three journal manuscripts, an introduction,

and an integrative discussion. The first manuscript examines potential habitat parameters

for monitoring landlocked Arctic Char condition in three lakes on Banks Island in the

Inuvialuit Settlement Region. The second manuscript examines potential local

environmental parameters for monitoring landlocked Arctic Char growth in the same three

lakes. The third manuscript investigates aspects of Arctic Char community-based

monitoring programs (CBMP) in the Canadian North that have led to the sustained

collection of useful data for management of the resource.

This dissertation makes contributions to the field of research by demonstrating the

utility of a mixed methods approach. The results demonstrate similarities and differences

in char growth and condition within and among Capron, Kuptan and Middle lakes on Banks

Island. This supports both lake-specific and regional climate-driven changes, meaning both

lake habitat and local environmental monitoring parameters should be used in char CBMP.

The investigation of char CBMP across northern Canada demonstrates that an adaptive

monitoring approach is important for subsistence fisheries, as changing lifestyles and

environmental changes impacting a fishery can have direct effects on the successful

operation of char CBMP.

Author Keywords: Arctic Char, community-based monitoring, environment, Inuit Knowledge, mixed methods, Traditional Knowledge

The spatial and temporal variation in atmospheric nitrogen dioxide (NO2), ammonia (NH3), and 17 elements (V, Cr, Fe, Ni, Cu, Zn, As, Cd, Pb, Mg, Al, Ca, Co, Se, Sb, Mn, and Na) were measured at 40 road side locations along a ~250 km traffic density gradient of 40,000–400,000 vehicles on the King's Highway 401, in Ontario, Canada. Elemental concentrations were measured over a year, using moss bags as passive samplers, for four quarterly three-month exposure periods (October 2015 – October 2016). Gaseous NO2 and NH3 concentrations were measured using Willem's badge passive diffusive samplers for twelve one-week exposure periods (one per month: October 2015–October 2016). Dry deposition of nitrogen was estimated using the inferential method. There were significant linear relationships between NO2 and NH3 and average annual daily traffic (AADT) volumes across the study area; higher concentrations corresponded to higher volume traffic sites. Average NO2 concentrations at sites ranged from 23.5 to 73 μg/m3, with an annual average of 43.7 μg/m3. Ammonia ranged from 2.56 to 13.55 μg/m3, with an annual average of 6.44 μg/m3. There were significant quarterly variations in NO2, with concentrations peaking during the winter months. In contrast, NH3 showed no significant quarterly variation, but a slight peak occurred during the summer. Gaseous NO2 and NH3 were highly positively correlated (r = 0.63), suggesting a common emission source from traffic. Concentrations in exposed moss were determined by subtracting the total concentration of each metal in the exposed sample from the background concentration present in the moss. Relative accumulation factors (RAF) and contamination factors were also calculated to determine the anthropogenic influence on tissue concentrations in exposed moss. All metals showed elevated levels versus background concentrations, with all metals except Ni and Co showing considerable enrichment. The highest levels of contamination were from V, Cr, Fe, Zn, Cd, Sb, Pb and Na. Principal component analysis indicated 5 clear clusters of related elements, with PC1 accounting for 36.2% and PC2 accounting for 25.6% of the variance. Average annual daily traffic was significantly related to Cr, Fe, Cu, Sb, Mn, Al, and Na. Road side monitoring shows consistently higher concentrations than active monitoring sites located further from the edge of the road, indicating a need for increased road side monitoring in Ontario, Canada.

According to the Invasional Meltdown Hypothesis (IMH), invasive species may interact in their introduced range and facilitate future invasions. This study investigated the possibility that Alliaria petiolata, an invasive allelopathic herbaceous plant in Ontario, is facilitating invasions by additional alien species. Two allelopathic focal species were chosen for this study: the native Solidago canadensis and the invasive A. petiolata. Field surveys in southern Ontario that quantified plant biodiversity in plots that included one or both focal species revealed no support for the IMH, although fewer species co-existed with A. petiolata than with S. canadensis. A year-long recruitment experiment in Peterborough, Ontario, also produced results inconsistent with the IMH, although did provide some evidence that A. petiolata limited recruitment of other species. These results collectively show negative impacts on regional biodiversity by A. petiolata, even in the absence of an invasional meltdown.

Author Keywords: allelopathy, Alliaria petiolata, co-occurrence surveys, invasional meltdown hypothesis, invasive species, Solidago canadensis