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Theses/Dissertations

2021

Ecology and Evolutionary Biology

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Full-Text Articles in Life Sciences

Fine Scales, Broad Consequences: Drivers And Effects Of Microclimatic Variation In Great Smoky Mountains National Park, Jordan Rebecca Stark Dec 2021

Fine Scales, Broad Consequences: Drivers And Effects Of Microclimatic Variation In Great Smoky Mountains National Park, Jordan Rebecca Stark

Theses - ALL

Climate is highly variable at scales that are not captured by most weather and climate models due to local effects of topography and living systems. This variation in microclimate has been noted for many decades but has been difficult to incorporate into quantitative understanding of ecological systems and processes due to the large amount of data and complex models required to adequately describe fine-scale patterns across complex landscapes. In recent years, models of thermal microclimate variation have been developed using low-cost temperature sensors, but few of these models have been used to predict the effects of microclimatic variation on ecological …


Using Spatial Methods To Analyse Anthropogenic Predation Risk And Movement Ecology Of White-Tailed Deer (Odocoileus Virginianus), Rhiannon D. Kirton Dec 2021

Using Spatial Methods To Analyse Anthropogenic Predation Risk And Movement Ecology Of White-Tailed Deer (Odocoileus Virginianus), Rhiannon D. Kirton

Electronic Thesis and Dissertation Repository

Hunting has been used as a central tool by wildlife managers to maintain populations of game species, however, we still lack a good understanding of exactly how hunting influences deer biology. Technological advances in GPS data over the last two decades now enable us to perform more detailed analysis on the effects of human hunters on wildlife populations. This research explores the spatial ecology of hunters and White-tailed deer in the Cross Timbers ecoregion of Oklahoma. Using new statistical methodologies to analyse simultaneous GPS tracking data on deer and hunters to study their spatial interactions. The results show how new …


Retroviral Infection Dynamics In Maine's Wild Turkeys, Stephanie A. Shea Dec 2021

Retroviral Infection Dynamics In Maine's Wild Turkeys, Stephanie A. Shea

Electronic Theses and Dissertations

Widespread wild turkey reintroductions in the late 1900s have led to increases in population density and geographic distribution across North America. This rapid population expansion has put them into proximity with closely-related wild and domestic avian species, increasing the risks of pathogen transmission. Lymphoproliferative disease virus (LPDV) is an avian oncogenic retrovirus detected in wild turkeys in 2009, and previously known to infect domestic turkeys. Following its initial detection, surveys reported variable LPDV prevalence across eastern North America with most wild turkeys being asymptomatic, however diagnostic cases revealed 10% mortality of LPDV-infected individuals. Given its recent detection, little is known …


Coyote Management In San Francisco, Matthew Greer Dec 2021

Coyote Management In San Francisco, Matthew Greer

Master's Projects and Capstones

As cities in North America grow, coyotes have become progressively more important species in urban ecosystems. Moreover, as coyotes increasingly use these urban spaces, human-coyote conflicts have become more common, creating a need for new management strategies. This paper will explore how the city of San Francisco could create a new coyote management plan for its highly visible coyote population. San Francisco has had a persistent coyote population since the early 2000s (Todd, 2018). Currently, the coyote population is close to 100 individuals and is still growing (J. Young, Presidio Trust, pers. comm.). To explore this topic a literature review …


Joint Management Of Upland & Aquatic Habitat For The California Red-Legged Frog & California Tiger Salamander, Kyle E. Verblaauw Dec 2021

Joint Management Of Upland & Aquatic Habitat For The California Red-Legged Frog & California Tiger Salamander, Kyle E. Verblaauw

Master's Projects and Capstones

As federally and state protected amphibians, the California tiger salamander (Ambystoma californiense) and the California red-legged frog (Rana draytonii) are recipients of ample management focus. Both species face a variety of threats, including habitat loss and alteration, introduction of non-native species, spread of disease, and effects of climate change. While management plans for the California tiger salamander and California red-legged frog exist, they frequently do not consider both species in tandem and often contain multiple shortcomings. This document aims to address the shortfalls of current management by providing practical recommendations for jointly managing the upland and …


Fear Of The Human "Super-Predator" In African Mammals, Nikita R. Frizzelle Dec 2021

Fear Of The Human "Super-Predator" In African Mammals, Nikita R. Frizzelle

Electronic Thesis and Dissertation Repository

Humans’ exploitive killing of virtually every mammal species globally may result in a perception of humans as feared, ultra-lethal predators. In Africa, mammals are central to the continent’s tourism industry; however, it is largely unknown whether African mammals fear the presence of tourists. Firstly, I aimed to review how the presence of humans on the landscape affects African mammal behaviour. Of 31 studies, most authors reported that humans alter mammal behaviour in a manner that may negatively impact survival. To test if a fear of humans can pervade communities, I simulated the presence of humans, hunting, lions, and birds using …


Pushing It To The Limit: Determining Asian Elephant (Elephas Maximus) Olfactory Sensitivity And Discrimination Through A Behavioral Choice Task, Matthew S. Rudolph Dec 2021

Pushing It To The Limit: Determining Asian Elephant (Elephas Maximus) Olfactory Sensitivity And Discrimination Through A Behavioral Choice Task, Matthew S. Rudolph

Theses and Dissertations

Elephants have shown remarkable olfactory capabilities. Their sense of smell impacts their foraging choices, behavior, and ultimately, survival. Being able to detect a target odor can allow elephants to locate specific resources, identify threats, and find receptive conspecifics. Previous studies have shown that elephants can consistently detect target odors, but have not identified the limits of this detection. Thus, to investigate the extent of elephants’ odor detection capabilities, we tested Asian elephants in a two-step odor discrimination task. First, we investigated whether elephants could detect odors at varying levels of dilution after a training procedure, and then whether they could …


Energetic Tradeoffs, Infection, And Immunity In Wild Chimpanzees Of Uganda And Tanzania, Sarah Renee Phillips Dec 2021

Energetic Tradeoffs, Infection, And Immunity In Wild Chimpanzees Of Uganda And Tanzania, Sarah Renee Phillips

Anthropology ETDs

Infectious disease is a primary source of mortality for most mammal species, but scientists have little understanding of factors driving variation in infection and immunity between individuals, populations, and species in the wild. Life history theory provides an evolutionary framework for delineating distribution of available energy to competing physiological demands, including growth, reproduction, and maintenance. Early life reproduction should be favored over late life survival, but, in long-lived species, reproductive success is strongly tied to survival to old age. Slower pace of reproduction could allow investment in immunity, reducing risk of morbidity and mortality to infectious disease. Additionally, several host …


An Assessment Of The Diverse Freshwater Turtle Fauna Of Mississippi, Lucas Haralson Dec 2021

An Assessment Of The Diverse Freshwater Turtle Fauna Of Mississippi, Lucas Haralson

Master's Theses

Nestled within the Southeastern United States Turtle Priority Area, Mississippi boasts impressive freshwater turtle diversity and is home to 8.6% of extant turtle species. Despite this impressive richness, few studies have assessed freshwater turtle assemblages in this hotspot of aquatic diversity. This research aimed to elucidate the distributions and abundances of freshwater turtle species through a statewide investigation of all major river drainages of the state. Using baited hoop nets (90 cm and 120 cm diameter), turtles were collected, identified to species and sex, and measured, before being released. Turtle assemblages were assessed in both lotic and lentic environments from …


Spatiotemporal Variation Of An Eastern Tropical Pacific Pelagic Community Assessed With Free-Drifting Bruvs, Tyler Stephen Plum Dec 2021

Spatiotemporal Variation Of An Eastern Tropical Pacific Pelagic Community Assessed With Free-Drifting Bruvs, Tyler Stephen Plum

All HCAS Student Capstones, Theses, and Dissertations

Information about pelagic community diversity and ecology generally lags far behind that of coastal communities, and largely derives from fisheries data that do not reflect small and non-target species. We describe spatiotemporal vertebrate species diversity and variability over a 3,486 km2 area of highly productive pelagic marine ecosystem in Pacific Panama using drifting baited remote underwater video stations (BRUVS), a non-invasive fishery-independent sampling technique. We observed 26 taxa from 17 families, including 1 mammal, 3 reptile, 5 elasmobranch, and 17 teleost species. Community assemblages differed on and off the continental shelf and between wet (April – December) and dry …


Distribution, Abundance, And Population Genetics Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Mississippi, Luke Pearson Dec 2021

Distribution, Abundance, And Population Genetics Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Mississippi, Luke Pearson

Dissertations

The southeastern United States is a freshwater turtle biodiversity hotspot, second only to southeastern Asia, and this region is inhabited by one of the largest freshwater turtles in the world: the alligator snapping turtle (Macrochelys temminckii). This species was heavily harvested from the 1960’s to the 1980’s for the turtle soup industry, apparently contributing to substantial, range-wide population declines. These declines, coupled with anthropogenic impacts on riverine and floodplain habitats, have led to M. temminckii being petitioned for federal listing under the U.S. Endangered Species Act; it is currently under review by the U.S. Fish and Wildlife Service …


Small Mammal Community Ecology And Ectoparasite Dynamics In A Tamaulipan Thornscrub Habitat, Brandi Giles Dec 2021

Small Mammal Community Ecology And Ectoparasite Dynamics In A Tamaulipan Thornscrub Habitat, Brandi Giles

Theses and Dissertations

Small mammals play many roles in ecosystems and are known as great indicators of overall ecosystem function and health, but they are also highly competent hosts for ticks and tick-borne disease. In this study, I gathered data on small mammal community ecology and species diversity, abundance, and overall ectoparasite (i.e., ticks) dynamics in a south Texas Tamaulipan thornscrub habitat. I also assessed differences in these parameters in edge versus interior habitats across a gradient of habitat fragmentation and species assemblage. Lastly, I assessed which host and environmental factors can be utilized for predicting parasitization of small mammals in this habitat. …


A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley Dec 2021

A Systematic And Biogeographic Study Of Trillium (Melanthiaceae), Jayne A. Lampley

Doctoral Dissertations

Trillium (Melanthiaceae, Parideae) has a disjunct distribution occurring in eastern and western North America, and eastern Asia. Past studies have examined the phylogeny and historical biogeography of Melanthiaceae and Parideae, however these studies either did not fully examine these aspects within Trillium or did not employ sufficiently broad taxonomic or character sampling to clarify relationships among taxa. The first phylogenetic analysis presented in this study provides a resolved phylogeny for Trillium s.l. and Paris s.l. by using a dataset of 70 plastid coding genes and by sampling broadly from Trillium s.s., Pseudotrillium, Trillidium, Paris s.s., Daiswa, and Kinugasa. The results …


Geographic Patterns Of Genetic Diversity Under Climate Change: Linking Genes And Ecosystems, Shannon L. Bayliss Dec 2021

Geographic Patterns Of Genetic Diversity Under Climate Change: Linking Genes And Ecosystems, Shannon L. Bayliss

Doctoral Dissertations

Climate change is having profound effects on species distributions. However, much less is understood about how climate change may alter the distribution of genetic variation within species across landscapes. Maintaining genetic diversity within populations is essential for the survival of species in the face of rapid climatic changes, but importantly, losses of genetic variation will also have significant consequences on entire ecosystems. The objective of this dissertation is to understand how genetic variation in a riparian cottonwood species, Populus angustifolia, affects mass and energy exchange between the land and atmosphere across ~1700 km of latitude of the western United …


Microbial Community Dynamics Of A Microcystis Bloom, Helena Pound Dec 2021

Microbial Community Dynamics Of A Microcystis Bloom, Helena Pound

Doctoral Dissertations

Harmful algal bloom events are notoriously associated with massive economic and environmental consequences, causing wildlife and human health risks. As these blooms increase in occurrence, duration, and severity around the world, it is essential to understand conditions leading to bloom formation and why they persist. Abiotic factors such as nutrients are commonly considered in bloom dynamics, but biotic interactions with co-occurring microbial species and viruses must also be taken into account. Harmful algal blooms dominated by the cyanobacterial genus Microcystis occur in bodies of water around the world and provide an ideal system in which to study top-down controls on …


Shell Calcification And Growth Of The Aquatic Snail Planorbella Trivolvis Under Low Calcium Conditions Typical Of Decalcified Northern Lakes, Shawn A. Witte Dec 2021

Shell Calcification And Growth Of The Aquatic Snail Planorbella Trivolvis Under Low Calcium Conditions Typical Of Decalcified Northern Lakes, Shawn A. Witte

Biology Theses

The water calcium concentration of northern softwater lakes has declined to critically low levels due to numerous anthropogenic stressors, and the availability of calcium is expected to decline further. To assess the impact that critically low water calcium has on aquatic snail shell calcification and growth, juvenile Planorbella trivolvis were raised for 60 days in one of four treatments, each containing a different amount of dissolved calcium (0.64, 1.3, 2.5, and 5.1 mg/L). There was no difference in tissue weight or shell size among treatments, suggesting low water calcium concentrations do not impact adult body mass or size. However, snails …


Developmental And Behavioral Responses Of Early Life Stages Of Fathead Minnows (Pimephales Promelas) To Urban Effluents Treated With Advanced-Oxidation Processes, Amy Cavanaugh Dec 2021

Developmental And Behavioral Responses Of Early Life Stages Of Fathead Minnows (Pimephales Promelas) To Urban Effluents Treated With Advanced-Oxidation Processes, Amy Cavanaugh

Biology Theses

Wastewater Treatment Plants (WWTP) are the main vector for pharmaceutical and personal care products (PPCPs) to enter waterways. Many PPCPs are lipophilic, allowing them to bioaccumulate and biomagnify within aquatic organisms. PPCPs have been known to alter fish behavior and physiological processes, such as nesting defense and sex ratios, and produce an increase in deformities. Advanced oxidation processes (AOPs) are novel ways for treating WWTPs effluents that use hydroxyl radicals to indiscriminately breakdown PPCPs. In this study, fathead minnows (Pimephales promelas) were used to examine the biological effects of AOP-treated municipal effluent as they developed from eggs to …


Impacts Of Environmental And Anthropogenic Stressors On Amphibian Welfare, Diversity, And Distribution In The Upper Missouri River Basin, Kaitlyn Campbell Dec 2021

Impacts Of Environmental And Anthropogenic Stressors On Amphibian Welfare, Diversity, And Distribution In The Upper Missouri River Basin, Kaitlyn Campbell

Dissertations and Theses

Climate change and anthropogenic stressors have contributed to rapid declines among various taxonomic groups; however, amphibian declines have been particularly intense and primarily stemmed from warming temperatures, habitat loss, exposure to contaminants, disease, and their subsequent interactions. Several climate mitigation strategies, like Bioenergy with Carbon Capture and Storage, have been proposed to alleviate the impact of rising temperatures; however, these proposals often fail to recognize and quantify the true impact on fauna, including changes in species distributions. To address this critical gap in knowledge, this research identified current amphibian distributions in the Upper Missouri River Basin and projected distribution changes …


Linking Plot And Landscape Level Phenology, Alejandra Flores Dec 2021

Linking Plot And Landscape Level Phenology, Alejandra Flores

Open Access Theses & Dissertations

Plant phenology has become popularize since the 1990s to help understand the effects of climate change on vegetation, it is a way to study the patterns of leaf-out, flowering, and senescing of the life-cycle of the plant. The timing from start of season (SOS) to end-of-season (EOS) of plant leaf-out development has important implication on ecosystem productivity and carbon cycling across ecological scales from individual trees to whole regions. The need for plant phenology studies in dryland are highly anticipated, since they make up 40% of the terrestrial landscape and recently have shown the play an important role in the …


Organizational Networking, Leadership, And Community Engagement: A Case Study Of The Revitalization Of An Impaired Watershed In Richmond, Virginia, Julia L. Roller Dec 2021

Organizational Networking, Leadership, And Community Engagement: A Case Study Of The Revitalization Of An Impaired Watershed In Richmond, Virginia, Julia L. Roller

School of Professional and Continuing Studies Nonprofit Studies Capstone Projects

Green infrastructure is a necessary component of urban environments designed to mitigate climate instability and provide healthier living environments for urban residents. Discrimination and socio-economic status are some of the determining factors in the provision of green infrastructure, availability of green spaces, and outdoor programming available in urban communities. This paper describes an exploratory case study of the partnerships between municipal and nonprofit organizations involved in the revitalization of an impaired watershed in Richmond, Virginia. Preliminary findings suggest networking between agencies and nonprofits with strong mission alignment can increase organizational capacity by sharing specialized training and resources. Success may also …


Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee Dec 2021

Transport And Fate Of Phosphorus In The Nearshore Zone Of Lake Michigan, Nathan Van Ee

Theses and Dissertations

Bioavailable phosphorus loads exported to Lake Michigan from the Milwaukee and Sheboygan River Watersheds appear to have increased in the last 40 years despite meeting total phosphorus (TP) loading goals set by the Great Lakes Water Quality Agreement (GLWQA).Overall, bioavailability of P delivered from the Milwaukee and Sheboygan Rivers was highest during the warmer months, which coincides with the nearshore nuisance algae growth season. However, first order loss rates of SRP calculated during baseflow recession were also greatest during the summer, suggesting that increased river residence time during the summer could reduce export of bioavailable P. Observations of phosphorus partitioning …


Ecological Outcomes Of Movement Behavior In Brown Pelicans From The South Atlantic Bight, Bradley Wilkinson Dec 2021

Ecological Outcomes Of Movement Behavior In Brown Pelicans From The South Atlantic Bight, Bradley Wilkinson

All Dissertations

Vagile organisms are expected to display movement behaviors that respond to a wide variety of both intrinsic and extrinsic factors. Identifying drivers of movement is fundamental to understanding the ecology of species, as well as implementing effective conservation measures. Technological advancements have allowed for the collection of fine-scale positional data at rapid temporal scales, which can be a powerful tool for assessing the movement behavior of tracked species and for understanding the potential fitness implications resulting from variations in animal space use. The goal of this dissertation was to identify important drivers of movement behavior and to describe the ecological …


Comprehensive Study Of Human Pathogenic Trypanosomatids: From Chemotherapies To Disease Ecology, Felipe Rodriguez Dec 2021

Comprehensive Study Of Human Pathogenic Trypanosomatids: From Chemotherapies To Disease Ecology, Felipe Rodriguez

Open Access Theses & Dissertations

The vector-borne diseases Leishmaniasis and Chagas disease, caused by the kinetoplastid parasites Leishmania spp. and Trypanosoma cruzi respectively, are among the most important parasitic diseases in the group of neglected tropical diseases. Even though the two diseases are endemic to the Americas, they affect millions of people worldwide. Leishmaniasis and Chagas disease cause a great array of symptoms and some of them can be fatal if left undiagnosed and untreated. Current treatment regimens are becoming less effective, vaccines are still not available, and diagnosis needs to be improved. Vector control has been responsible for a decrease of diseases in endemic …


Gather Round The Tree: Woody Aboveground Biomass Increases Animal Presence And Species Richness In A Tropical Forest-Savanna Ecotone, Merry Vanessa Marshall Davidson Dec 2021

Gather Round The Tree: Woody Aboveground Biomass Increases Animal Presence And Species Richness In A Tropical Forest-Savanna Ecotone, Merry Vanessa Marshall Davidson

Boise State University Theses and Dissertations

Boundaries between ecosystems are often biodiversity hotspots with relatively high vulnerability to global change. The boundary between tropical rainforest and savanna ecosystems in the Amazon presents an ecotone that is undergoing a shift in ecosystem structure, as a warming climate promotes the expansion of grassland. How animal communities in the Amazon will respond to changes in ecosystem structure is a crucial unanswered question with implications for the many ecosystem services that animals provide, from a food source for Indigenous people to seed dispersal for vulnerable tree populations. Recent modeling work has forecasted that faunal savannization will occur in the Amazon, …


Effects Of Habitat Disturbances On Reptiles In Sagebrush Steppe, Kristina Joan Parker Dec 2021

Effects Of Habitat Disturbances On Reptiles In Sagebrush Steppe, Kristina Joan Parker

Boise State University Theses and Dissertations

Reptiles inhabiting shrub-steppe ecosystems of the Intermountain West have adapted to harsh, unpredictable desert conditions, yet recent changes in disturbance regimes may put species at risk. In southwest Idaho, cheatgrass (Bromus tectorum) has altered the fire regime resulting in a vast conversion of shrub-steppe to mostly annual grasslands that burn too frequently to allow shrublands to recover. Southwest Idaho has the highest reptile diversity in the Pacific Northwest, yet we know little about reptile community dynamics in response to the cheatgrass-fire cycle. We hypothesized that wildfires and cheatgrass negatively affect reptile communities directly (i.e., mortality during fires) and …


The Effects Of Commercial Harvest On The Density And Demography Of Aquatic Turtles In Arkansas, Andrhea Darleen Massey Dec 2021

The Effects Of Commercial Harvest On The Density And Demography Of Aquatic Turtles In Arkansas, Andrhea Darleen Massey

Graduate Theses and Dissertations

The United States is home to the second highest concentration of turtle species in the world, after Asia. As of 2018, there are 57 turtle species recognized within the US, 40% of which are listed as threatened or endangered, with the primary threats to population persistence identified as over-consumption and/or habitat loss. Within the US, the Mississippi Alluvial Valley (MAV) region represents the second highest turtle species richness, after the Mobile River Basin. The MAV region of Arkansas is one of the least regulated in terms of commercial aquatic turtle harvest and has undergone large-scale habitat conversion from bottomland hardwood …


From Microbes To Management: Spatial And Temporal Variations In Available Vegetation Affect The Gut Microbiota In A Population Of Free-Ranging Generalist Herbivores, Olivia K. Rodríguez Dec 2021

From Microbes To Management: Spatial And Temporal Variations In Available Vegetation Affect The Gut Microbiota In A Population Of Free-Ranging Generalist Herbivores, Olivia K. Rodríguez

Boise State University Theses and Dissertations

The effects of extrinsic environmental factors that shape ecological systems are not only seen at the macroscopic level, but additionally influence and govern the host-associated microbial communities of their mammalian hosts. These microbial communities are susceptible to the fluctuation of abiotic and biotic factors which affect their host organisms. The surge in the research of microbiota–communities of archaea, bacteria, fungi, and viruses residing in various environmental systems–has shown that these communities can profoundly influence animal health. As such, monitoring microbiota has allowed for a new approach to study animal health and physiology. This is of particular benefit in the conservation …


Cumulative Effects Of Habitat Change: American Marten Habitat Selection And 30 Years Of Forest Harvesting In Maine, Tyler Woollard Dec 2021

Cumulative Effects Of Habitat Change: American Marten Habitat Selection And 30 Years Of Forest Harvesting In Maine, Tyler Woollard

Electronic Theses and Dissertations

Wildlife habitat conservation in landscapes where human activities cause chronic habitat disturbance is contingent upon developing land management strategies that minimize the effects of future habitat changes on wildlife populations. Long term studies can provide unique opportunities to understand how species respond to progressive habitat change, and such an understanding can reveal ways in which the often conflicting objectives of wildlife habitat conservation and human land use can be reconciled. Characterizing how animals respond behaviorally to habitat conditions may be a useful tool for identifying potential negative effects of disturbance before such effects impact rates of species occurrence, population demography, …


Biotic Interactions At Species’ Range Limits In A Changing Climate, Isaac Shepard Dec 2021

Biotic Interactions At Species’ Range Limits In A Changing Climate, Isaac Shepard

Electronic Theses and Dissertations

As the global climate changes, many species are shifting their geographic ranges, often towards the poles or upslope in elevation. The ubiquity of these observation has renewed discussions about the mechanisms that determine species’ range margins. Leading hypotheses state abiotic variables should be the most important factor for setting range limits in environmentally stressful habitats. However, I propose an alternative hypothesis that biotic interactions may still be critically important for setting range limits, even in abiotically stressful habitats. Using a model system of ponds in the Rocky Mountains of Colorado, I developed several field experiments to empirically test the role …


Trophic Ecology Of Juvenile Lean And Siscowet Lake Trout (Salvelinus Namaychush) From U.S. Waters Of Lake Superior, Will Otte Dec 2021

Trophic Ecology Of Juvenile Lean And Siscowet Lake Trout (Salvelinus Namaychush) From U.S. Waters Of Lake Superior, Will Otte

All NMU Master's Theses

In this study, I investigated the spatial overlap, diet similarity, and isotopic niches of juvenile Lean and Siscowet Lake Trout ecotypes across six ecoregions of Lake Superior. Spatially, Lean and Siscowet were observed in overlapping depth distributions. Leans were most abundant in shallow waters (60m). The greatest levels of cohabitation were observed in waters from 40-60m. Trophic position (as measured by δ 15N) was similar for both ecotypes at small sizes (mm), but Siscowet exhibited a higher trophic position than Lean Lake Trout at larger sizes (>400mm) and older ages (>5 years). Base of production (as measured by …