Ecology

This study examines foraging strategies during the Middle Woodland Period's Sandbanks Phase (A.D. 700–1000) on Boyd Island, Pigeon Lake, Ontario. The faunal remains analyzed in this study were recovered from a site associated with the procurement of aquatic and terrestrial taxa. Detailed taphonomic analyses have revealed that the Boyd Island faunal remains were affected by weathering and human transport decisions. White-tailed deer was the most frequently acquired prey at Boyd Island, followed by black bear. Using the central place forager prey choice model as a framework, the analysis of diet breadth and carcass transport patterns suggests that most animal resources were acquired from both aquatic and terrestrial habitats, at moderate distances from the site. Incomplete carcasses of large game appear to have been transported away from the site, where they were subsequently processed for provisioning or consumption. Comparisons with other Sandbanks faunal assemblages and those dating to later periods indicate significant differences in terms of taxonomic composition, while continuing to emphasize the use of fish. It is suggested that the Middle Woodland foragers adopted subsistence strategies focusing on the exploitation of local habitats in which productivity may have been enhanced through niche construction associated with the low-level food production activities.

Author Keywords: animal resource exploitation, archaeozoology, foraging theory, Middle Woodland, niche construction theory, southcentral Ontario

Numerous prey taxa employ defensive postures for protection against attack by predators. Defensive postures mitigate predation risk at various stages of the predator-prey sequence, including through crypsis, mimicry, thanatosis, aposematism, and deflection. In terrestrial salamanders, defensive postures may be aposematic, or deflect attacks away from vital body parts and towards the tail, however the extent to which these strategies act exclusively or synergistically remains poorly understood. Herein I demonstrate a novel approach to study the function of salamander defensive postures through experimental manipulation of predator response to antipredator behaviour in a natural field setting. I deployed 1600 clay salamander prey on Pelee Island, Ontario, manipulating prey size (small, large) and posture (resting, defensive) and documented attack rates across three predator types to further assess the effect of prey body size and predator type on antipredator efficacy. My research suggests that irrespective of prey body size, defensive posture does not function through aposematism, but rather acts to deflect predator attacks to the tail, which is commonly noxious and expendable in terrestrial salamanders. An intriguing possibility is that this behaviour facilitates taste-rejection by predators. Overall, my research should further contribute to our understanding of the importance and potential evolutionary significance of defensive posturing in Ambystoma salamanders, and more broadly, on the determinants of prey vulnerability to predation. I also briefly discuss the implications of my results to the conservation of Ambystoma populations on Pelee Island.

Author Keywords: Anti-predator behaviour, Aposematism, Attack deflection, Predator avoidance, Small-mouthed salamander, Taste-rejection

The Kentucky coffee tree (Gymnocladus dioicus) is an endangered tree species native to the American Midwest and Southwestern Ontario. Significant habitat loss and fragmentation due to agricultural, industrial and urban development has caused gradual decline across its native range. The aims of this study were to investigate: (1) patterns of genetic diversity and, (2) genetic differentiation (3) relative levels of sexual vs. clonal reproduction, and (4) potential for reduced genetic diversity at range edge for wild G. dioicus populations. An analysis of variation at nine microsatellite loci from populations in the core of the species distribution in the U.S.A. and 4 regions of Southwestern Ontario indicated that G. dioicus has remarkably high genetic similarity across its range (average pairwise FST= 0.05). Germination trials revealed that the seed coats require highly invasive treatments (e.g. 17.93 mol/L H2SO4) to facilitate imbibition, with negligible germination observed in treatments meant to emulate prevailing conditions in natural populations. Low levels of sexual reproduction, high genetic similarity, and habitat degradation are issues that exist across the entire native range of G. dioicus.

I assessed how organisms having multiple biotic attributes may have conflicting niche determinants, and whether the realized niche reflects single or multiple attributes. All-female salamanders engage in two biotic states: hybridism and reproductive parasitism. Hybrids should occupy areas transitional to those used by parental species, whereas parasites that engage in competition with hosts should occupy habitats moderately suitable for hosts. Using niche models, I predicted realized niches for unisexual Ambystoma via a hybrid model (environmental predictors) and a parasite model (host suitability predictors). The hybrid model predicted that the unisexual niche would indeed be transitional between parental Ambystoma spp. The parasite model demonstrated unisexual salamanders occupied habitats moderately suitable for hosts, though model validation did not fully corroborate its predictive power. The hybrid model was more descriptive of unisexual occurrence than the parasite model. When species have competing ecological roles a primary biotic attribute may largely derive the realized niche.

Author Keywords: Ambystoma, hybrid, niche, parasite, range, unisexual

Hunting represents the principal tool for managing populations of migratory caribou (Rangifer tarandus), but harvest may be affected by landscape features that govern animal distribution and hunter access. Such effects are unclear. I capitalized on an existing dataset of 21 355 caribou harvest records, 1980 – 2009, to determine the influence of landscape features on caribou harvest across the island of Newfoundland. Using a landcover map and spatial data for anthropogenic features, I modelled caribou harvest at the island scale for three phases of numerical change (growth in the 1980s, cessation of growth in the 1990s, decline in the 2000s) and harvest type (total harvest, resident harvest of males and females, resident harvest of males, resident harvest of females, and non-resident harvest of males) in relation to multiple putative predictor variables: proportion of lichen cover and distances to nearest forest cut, road, outfitter, transmission line, and town. I did the same analysis for seven individual Caribou Management Areas (CMAs).

At the island scale, the number of harvested caribou increased with proximity to the nearest forest cut and with greater proportions of lichen habitat. I attribute this to landscape features that provide forage for caribou, but also access and caribou visibility for hunters. Caribou harvest increased in proximity to transmission lines for the harvest of caribou by resident hunters in the 2000s, which could be a result of more risk-prone foraging Newfoundland caribou. Non-resident hunters harvested greater numbers of male caribou further from towns, likely a result of the placement of outfitter camps and activities. At the management area scale, in most instances, more caribou harvest occurred in close proximity to transmission lines. Proximity to forest cuts and high proportions of lichen were still important landscape features leading to a greater harvest. I conclude that the caribou harvest was largely governed by hunter access and visibility of their prey, augmented by open habitats preferred by caribou.

KEYWORDS

Caribou, Newfoundland, Rangifer tarandus, harvest, hunting, management area, landscape, human disturbances, game species vulnerability.

Author Keywords: caribou, game species vulnerability, harvest, hunting, newfoundland, rangifer tarandus

The growth of immature insects that develop on human remains can be used to estimate a post-mortem interval (PMI). PMI estimate confidence is negatively affected by: larval killing and preservation methods altering their size, limited morphological parameters to assess larval growth and therefore age, and few available alternate species development data. I compared live specimens to preserved specimens of the same development stages to assess the effects of killing-preservation techniques on morphology, and I introduce a new method that uses digital photography to examine maggot mouthparts for stage grading of Phormia regina. Digital photographic methods enable live insects to be quantified and improve approximations of physiological age. I then use these digital methods to produce a growth-rate model for a beetle commonly found on human remains, Necrodes surinamensis, providing data for PMI estimates that was previously unavailable.

Author Keywords: Forensic Entomology, Insect development, Morphometrics, Necrodes surinamensis, Phormia regina, Postmortem interval

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

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

Within the complex socio-ecological systems of South and Southeast Asia, ancient sacred natural sites were created by, and imbued with, cultural and ideological values. These landscapes are liminal spaces or threshold environments between cultivated areas and wilder spaces; the practice of creating and maintaining them persists from ancient to modern times. This thesis examines sacred natural sites in three early state formations from 800 – 1400 CE: the Khmer (Cambodia), the Sinhalese (Sri Lanka) and the Chola (South India), why they persisted over time, and what significance they held. Several ancient sacred natural sites are active parts of societies today, and the ones chosen for this study span several categories: mountains, rivers, forests/groves, and caves. Using the paradigm of entanglement theory in a comparative context, this thesis analyzes sacred natural sites acting as key socio-ecological nodes enmeshed in complex dependent relationships within the landscapes of the South and Southeast Asia.

Author Keywords: Comparative study, Entanglement theory, Sacred natural sites, Socio-ecological systems, South Asia, Tropical Societies

While the harvest of mammals is monitored in each jurisdiction across Canada and the USA, there has been no analysis of this wild harvest at a continental scale across North America. The recreational wild harvest of large mammals varies geographically across North America, and I hypothesized that this variation is influenced by both anthropogenic and other environmental factors on the landscape. I tested this hypothesis using annual harvest tallies collected by Conservation Visions Inc. for mammals for each state, provincial, and territorial jurisdiction in Canada and the USA. I built multiple additive models of the harvest, in one harvest year, 2015 – 2016, to test for landscape gradients that explain the variation in harvest levels for seven large mammal species: white-tailed deer (Odocoileus virginianus), black bear (Ursus americanus), bighorn sheep (Ovis canadensis), elk (Cervus canadensis), mule deer (Odocoileus hemionus), pronghorn (Antilocapra americana), and moose (Alces alces). I built these models from a suite of nine putative predictor variables that comprised landcover, human footprint, and evapotranspiration. For all large mammal species except for pronghorn, anthropogenic influence had a positive effect on the wild harvest density, consistent with the idea that the proximity of human populations and roads are important for fostering wild harvest activity by providing hunters access to hunting areas. The harvest of white-tailed deer, elk, and pronghorn were negatively affected by vegetation structure, urbanization, and primary productivity, respectively. Understanding the recreational wild harvest at a broad-spatial scale provides a unique perspective of the North American model of wildlife conservation and spurs future comparative analyses of the wild harvest across spatial scales.

Author Keywords: Anthropogenic Influence, Hunting, Large Mammals, Primary Productivity, Vegetation Structure, Wild Harvest