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Articles 1 - 30 of 44
Full-Text Articles in Animal Sciences
Differential Migration Timing And The Form And Function Of Avian Wings, Jessica E. Deakin
Differential Migration Timing And The Form And Function Of Avian Wings, Jessica E. Deakin
Electronic Thesis and Dissertation Repository
A common differential migration strategy in birds is protandry, whereby males arrive earlier than females. The probable causes of protandry are well studied from the perspective of innate and physical environmental cues, but the influence of the social environment and wing morphology are less known. Theoretical models propose that sex ratio influences protandry; male-biased sex ratios are predicted to advance timing in males due to increased intrasexual competition. To empirically test this, I investigated the spring migration traits of male Yellow-rumped Warblers Setophaga coronata under differing sex ratios. An integrated automated telemetry approach was used, where locomotor movement of captive …
Neural Responses To Magnetic Orientation Information In Songbirds, Madeleine Ir Brodbeck
Neural Responses To Magnetic Orientation Information In Songbirds, Madeleine Ir Brodbeck
Electronic Thesis and Dissertation Repository
Effective navigation and orientation is essential for animals to survive. The study of migratory birds provides insights into these processes, particularly through mechanisms like the geomagnetic compass, which uses Earth's magnetic field for directional information. A brain region in songbirds relevant to this is cluster N, known for its potential role in processing geomagnetic information. Notably, cluster N appears exclusive to nocturnally migratory birds, being active solely at night, and lesion studies reveal that an intact cluster N is necessary for geomagnetic compass orientation. However, given the scarcity of empirical data concerning cluster N, substantial questions persist regarding its function. …
Random Mating In The Face Of Balancing Selection At The Major Histocompatibility Complex Class I In Song Sparrows (Melospiza Melodia), Scout R.L Thompson
Random Mating In The Face Of Balancing Selection At The Major Histocompatibility Complex Class I In Song Sparrows (Melospiza Melodia), Scout R.L Thompson
Electronic Thesis and Dissertation Repository
The major histocompatibility complex (MHC) is a large group of genes encoding cell-surface proteins that recognize and bind pathogens to initiate an adaptive immune response. MHC loci experience intense pathogen-mediated selection which may be directional, where specific alleles provide the best disease protection, or balancing, where rare alleles or diverse combinations are most protective. However, balancing selection (specifically heterozygote advantage) is more common and often accompanied by disassortative mating. I sought to use genetic and behavioural information to evaluate whether balancing selection and disassortative mating occur at MHC class I (MHCI) in a population of song sparrows (Melospiza melodia …
The Role Of Serotonin In The Estradiol-Dependent Selectivity Of Auditory Regions In Songbirds, Calista J. Henry
The Role Of Serotonin In The Estradiol-Dependent Selectivity Of Auditory Regions In Songbirds, Calista J. Henry
Electronic Thesis and Dissertation Repository
Breeding-typical levels of estradiol in songbirds has been shown to lead to selective auditory processing and induce a release of serotonin in auditory regions of the forebrain. These findings triggered the question of whether auditory discrimination is driven by estradiol directly, or by the associated release of serotonin. I treated non-breeding female white-throated sparrows (Zonotrichia albicollis) with either blank implants, 17β-estradiol, serotonin enhancer and blank implants, or serotonin antagonist and 17β-estradiol implants. Birds then heard male conspecific songs or control tones, and ZENK-immunoreactivity was quantified in the caudomedial nidopallium (NCM) and caudomedial mesopallium (CMM). While I did not …
The Effect Of Dietary Thiaminase On Cardiac Function And Morphology In Lake Trout (Salvelinus Namaycush), Peter Baker
The Effect Of Dietary Thiaminase On Cardiac Function And Morphology In Lake Trout (Salvelinus Namaycush), Peter Baker
Electronic Thesis and Dissertation Repository
Thiamine deficiency from the consumption of invasive, high-thiaminase prey fishes is considered to be a major barrier for lake trout restoration in the Great Lakes. In fishes, an understudied aspect of thiamine deficiency is its effect on cardiac function. I examined the effects of dietary thiaminase on cardiac function and morphology in lake trout, specifically as they relate to thermal tolerance. Two hatchery strains of lake trout (Seneca and Slate) were raised on a control or thiaminase diet for nine months. The thiaminase diet was associated with significant ventricle enlargement, impaired cardiac function, and reduced thermal tolerance; these effects were …
Post-Breeding Survival Of Adult And Hatch-Year Bank Swallows (Riparia Riparia) In The Great Lakes Region: A Radio Telemetry Study, Christian M.M Buchanan-Fraser
Post-Breeding Survival Of Adult And Hatch-Year Bank Swallows (Riparia Riparia) In The Great Lakes Region: A Radio Telemetry Study, Christian M.M Buchanan-Fraser
Electronic Thesis and Dissertation Repository
The post-breeding period poses significant threats to newly fledged birds due to predation, starvation, exposure to inclement weather, and collision risk prior to their first southward migration. I used automated radio telemetry to track 100 adult and 100 hatch-year Bank Swallows (Riparia riparia) in the Great Lakes ecoregion during the 2021 post-breeding period. Additionally, 74 hatch-year birds tracked in 2018 by Mitchell et al. were included. In 2021, daily apparent survival probability was higher for adults compared to hatch-years; we estimated that ~10% of hatch-year birds die within two weeks post-fledging but high rates of tag loss in …
Effects Of Methylmercury And Unpredictable Food Stress Exposure On Songbirds’ Physiology And Seasonal Transition, Claire L.J. Bottini
Effects Of Methylmercury And Unpredictable Food Stress Exposure On Songbirds’ Physiology And Seasonal Transition, Claire L.J. Bottini
Electronic Thesis and Dissertation Repository
Organisms regularly adjust their physiology to respond to predictable seasonal or environmental variation. However, annual cycle transitions could be disrupted by contaminants or stressors. For example, methylmercury and stress exposure can independently disrupt birds’ neural and endocrine systems, energy balance, metabolism, or behaviour, all necessary for seasonal transitions. Although, the effects of combined exposure to stressors and methylmercury (MeHg), and how long they last after exposure ends, are poorly understood. The objective of my PhD was to evaluate the impact of MeHg exposure on songbirds’ physiology and its potential carry-over effects on seasonal transitions. I exposed song sparrows (Melospiza …
Using Spatial Methods To Analyse Anthropogenic Predation Risk And Movement Ecology Of White-Tailed Deer (Odocoileus Virginianus), Rhiannon D. Kirton
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 …
Diversity And Drivers Of Oribatid Mites (Acari: Oribatida) In Boreal Peatlands, Carlos Rafael De Araujo Barreto
Diversity And Drivers Of Oribatid Mites (Acari: Oribatida) In Boreal Peatlands, Carlos Rafael De Araujo Barreto
Electronic Thesis and Dissertation Repository
Boreal peatlands are important ecosystems for carbon cycling, storing 1/3 of the world’s terrestrial carbon in only ~3% of the globe, making them a key component of potential mitigation strategies in response to global climate warming. Experiments have shown that warming can affect plant and microbial communities in ways that potentially shift peatlands from carbon sinks to sources. Soil food webs, including the microarthropod community, are key in carbon cycling but are relatively understudied both in peatlands and under experimental warming. My research capitalized on a large-scale experimental field manipulation of warming in two contrasting peatland sites in Northern Ontario, …
Fishing For The Right Probiotic: Investigating The Mechanism Of Mucosal-Bacterial Interactions At The Interface Of Health And Productivity In Salmonid Aquaculture, Luana Langlois
Electronic Thesis and Dissertation Repository
Aquaculture is vital for the global food supply, but the high incidence of infectious diseases threatens the industry’s productivity. The intestinal mucosa is a key port of entry for pathogens and provides an extensive interface for host-microbe interactions. Tight junctions are at the core of gut barrier function and the mucosal health of finfish. Disruption of these complexes gives rise to sepsis, which leads to systemic inflammation and death. The present study employs a combinatorial approach that integrates in vitro and in vivo analyses to gain actionable insights into the mechanism of microbial-mediated modulation of host health. The experiments outlined …
Food Caching Decisions In Canada Jays (Perisoreus Canadensis), Robert J. Martin
Food Caching Decisions In Canada Jays (Perisoreus Canadensis), Robert J. Martin
Electronic Thesis and Dissertation Repository
Food scarce periods pose serious challenges for birds, particularly when those periods coincide with demanding life history stages such as overwintering. For resident birds in the Northern hemisphere, resource scarcity typically occurs simultaneously with winter conditions. In order to combat these compounded stressors, some species cache food to ensure a reliable supply of resources. Food caching is the storing of food items for subsequent retrieval and consumption after some delay. Canada Jays (Perisoreus canadensis) are year-round residents of the North American boreal forest and some high elevation areas in the United States, and cache food to combat resource …
Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell
Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell
Electronic Thesis and Dissertation Repository
The fitness of reintroduced salmonids in Lake Ontario can be reduced by high levels of thiaminase in exotic prey consumed at the adult stage. If sensitivity to dietary thiaminase differs among the three Atlantic salmon populations targeted for reintroduction into Lake Ontario, this could significantly influence their performance. I quantified the effects of experimental diets that contained high or low (control) levels of thiaminase on thiamine concentrations, survival, growth rate, and reproductive traits (sperm and egg quality) in Atlantic salmon from the three candidate source populations. Fish that consumed the high-thiaminase diet had comparable growth rates, but lower survival and …
Weathering The Storm: Physiological And Behavioural Responses Of White-Throated Sparrows To Inclement Weather Cues, Andrea C. Boyer
Weathering The Storm: Physiological And Behavioural Responses Of White-Throated Sparrows To Inclement Weather Cues, Andrea C. Boyer
Electronic Thesis and Dissertation Repository
Changes in weather patterns and extreme weather events are becoming more common with the onset of climate change. This predicted increase in severe weather globally is alarming and it draws concern for the adaptability and ultimate survival of many species. It is clear that birds are able to cope with and respond to inclement weather with physiological and behavioural responses in many circumstances, but as environmental conditions become more severe, the adaptive coping responses of many species may be pushed to their limit. As such, it is important to understand the effects that such changes in environmental conditions will have …
Hitchhiker's Guide To Migration: Effects Of Experimental Parasitic Infection And Other Immune Challenges On Migratory Traits Of Sparrows, Tosha R. Kelly
Hitchhiker's Guide To Migration: Effects Of Experimental Parasitic Infection And Other Immune Challenges On Migratory Traits Of Sparrows, Tosha R. Kelly
Electronic Thesis and Dissertation Repository
Seasonal migration exposes animals to a variety of habitats and parasites, and if infected migratory birds migrate successfully there is great potential for birds to transport infectious diseases long distances. Our current understanding of whether birds contribute to the spread of disease relies upon observational field studies that are limited in their ability to discern cause from effect. Using captive and field-based experiments for my doctoral research, I answered three research questions: (1) are nocturnal migratory restlessness (Zugunruhe) and body condition affected by mounting an acute phase immune response during migration; (2) what are the impacts of parasitic …
The Effects Of Perceived Predation Threat On Stress Response And Memory In Birds, Chlöe S. N. Carter
The Effects Of Perceived Predation Threat On Stress Response And Memory In Birds, Chlöe S. N. Carter
Electronic Thesis and Dissertation Repository
This study examined how perception of predator cues, across three sensory modalities, affects physiology and behaviour of songbirds. I hypothesized that the perception of predator threat would elicit physiological and behavioural responses in both acute and chronic exposure conditions. My first study examined the responses of wild-caught black-capped chickadees (Poecile atricapillus) and house sparrows (Passer domesticus), as well as lab-bred zebra finches (Taeniopygia guttata), to acute predation cue exposure by coding video recorded behaviour and corticosterone analysis. My second study examined changes in black-capped chickadees’ foraging behaviour and memory retention after chronic exposure to …
The Effect Of Shelter Availability On Foraging In Atlantic Salmon (Salmo Salar), Christian A. Therrien
The Effect Of Shelter Availability On Foraging In Atlantic Salmon (Salmo Salar), Christian A. Therrien
Electronic Thesis and Dissertation Repository
Shelter is an environmental feature that provides protection from danger and its use is an important anti-predator behavior for juvenile Atlantic salmon (Salmo salar). However, how shelter availability influences the foraging of these fish in the wild is not well documented. I predicted that juvenile Atlantic salmon would alter their foraging behavior in a low shelter environment and that this effect would differ between individuals from two populations that are targeted for reintroduction into Lake Ontario. I measured the foraging activity of juvenile Atlantic salmon from the two populations while they were held in pens in a Lake …
Circannual Patterns Of Adipose Tissue Characteristics In A Hibernator, The Thirteen-Lined Ground Squirrel (Ictidomys Tridecemlineatus), Amanda Maccannell
Circannual Patterns Of Adipose Tissue Characteristics In A Hibernator, The Thirteen-Lined Ground Squirrel (Ictidomys Tridecemlineatus), Amanda Maccannell
Electronic Thesis and Dissertation Repository
Obligate hibernators express circannual patterns of body mass and hibernation, which persist under constant laboratory conditions. I hypothesized that in the 13-lined ground squirrel (Ictidomys tridecemlineatus) thermogenic brown adipose tissue (BAT) and lipid storing white adipose tissue (WAT) volume would follow a circannual pattern. I housed animals at either 25°C (thermoneutral) or 5°C with 12h L:12h D photoperiods for an entire year. I determined volume and water-fat ratio of WAT and BAT using magnetic resonance imaging (MRI). BAT volume follows a circannual pattern in both conditions, increasing prior to winter, decreasing in late winter with no change in …
Resource Selection, Survival, And Departure Of Adult Female Mallards From The Lake St. Clair Region During Autumn And Winter, Matthew Palumbo
Resource Selection, Survival, And Departure Of Adult Female Mallards From The Lake St. Clair Region During Autumn And Winter, Matthew Palumbo
Electronic Thesis and Dissertation Repository
During autumn and winter, mallards (Anas platyrhynchos) maximize fitness through their spatiotemporal distribution to avoid mortality risks while balancing trade-offs to access foods to undergo migration and maintain homeostasis. Thousands of mallards use Lake St. Clair as it is an important, but threatened, migratory staging area in the Great Lakes. My goal was to understand how mallards were selecting resources in the region and potential relationships of selection strategies. My objectives were to estimate resource selection of adult female mallards, in relation to perceived risk of hunting mortality, and determine if selection strategies were related to survival and …
Regulation Of Liver Mitochondrial Metabolism During Hibernation By Post-Translational Modification, Katherine E. Mathers
Regulation Of Liver Mitochondrial Metabolism During Hibernation By Post-Translational Modification, Katherine E. Mathers
Electronic Thesis and Dissertation Repository
Hibernation, characterized by a seasonal reduction in metabolism and body temperature, allows animals to conserve energy when environmental conditions (e.g. temperature, food availability) are unfavourable. During hibernation, small mammals such as the 13-lined ground squirrel (Ictidomys tridecemlineatus) cycle between two distinct metabolic states: torpor, where metabolic rate is suppressed by >95% and body temperature falls to ~5 °C, and interbout euthermia (IBE), where metabolic rate and body temperature rapidly increase and are maintained at euthermic levels several hours. Suppression of metabolism during entrance into torpor is paralleled by rapid suppression of liver mitochondrial metabolism. In my thesis, I …
Modelling Walleye Population And Its Cannibalism Effect, Quan Zhou
Modelling Walleye Population And Its Cannibalism Effect, Quan Zhou
Electronic Thesis and Dissertation Repository
Walleye is a very common recreational fish in Canada with a strong cannibalism tendency, such that walleyes with larger sizes will consume their smaller counterparts when food sources are limited or a surplus of adults is present. Cannibalism may be a factor promoting population oscillation. As fish reach a certain age or biological stage (i.e. biological maturity), the number of fish achieving that stage is known as fish recruitment. The objective of this thesis is to model the walleye population with its recruitment and cannibalism effect. A matrix population model has been introduced to characterize the walleye population into three …
Autumn Foraging And Staging Ecology Of Eastern Population Sandhill Cranes (Antigone Canadensis Tabida), Everett E. Hanna
Autumn Foraging And Staging Ecology Of Eastern Population Sandhill Cranes (Antigone Canadensis Tabida), Everett E. Hanna
Electronic Thesis and Dissertation Repository
Spatial and temporal variation in the density and distribution of waste agricultural grain (grain herein) during staging can affect the carrying capacity of habitats that support avian populations. Such variation in food resources can also have proximate effects on behavioural ecology (e.g., influence optimal behaviour). The Eastern Population of Greater Sandhill Cranes (Antigone canadensis tabida; EP herein) likely began to recolonize Ontario and its historic range starting in the early 1900s and now relies on agricultural grain during migration. Accordingly, ecologists possess little knowledge of how EP crane behavioural ecology may be affected by grain. Thus, my study …
Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot
Evolutionary Genetic Aspects Of Host Association In Generalist Ectoparasites, Benoit Talbot
Electronic Thesis and Dissertation Repository
Despite the use of the host for dispersal by most parasite species, the extremely loose relationship typical between highly mobile hosts and generalist ectoparasites may lead to very different gene flow patterns between the two, leading in turn to different spatial genetic structure, and potentially different demographic history. I examined how similar gene flow patterns are between Cimex adjunctus, a generalist ectoparasite of bats present throughout North America, and two of its key bat hosts. I first analyzed the continent-scale genetic structure and demographic history of C. adjunctus and compared it to that of two of its hosts, the …
The Effects Of Crossbreeding And Low Fish Meal Diets On Growth-Related Traits In Chinook Salmon (Oncorhynchus Tshawytscha), Katarina H. Doughty
The Effects Of Crossbreeding And Low Fish Meal Diets On Growth-Related Traits In Chinook Salmon (Oncorhynchus Tshawytscha), Katarina H. Doughty
Electronic Thesis and Dissertation Repository
Growth rate is the most important trait that can be manipulated to create more efficient aquaculture. Crossbreeding, where different populations are bred, has the potential to increase performance through release from inbreeding depression. I crossed a farm population of Chinook salmon (Oncorhynchus tshawytscha) with seven wild populations, then compared growth rate, feed conversion efficiency, swimming speed and metabolic rate between the crossbred and original farmed lines. Crossbreeding resulted in increased growth rates, but had no effect on the other traits. I next evaluated the feasibility of using a diet that replaced fish meal with corn gluten meal and …
The Mixed Source Chinook Salmon Fishery In Lake Huron: A Comparison Of Spawning And Foraging Habitat Use By Naturalized And Hatchery Fish, Stephen A.C. Marklevitz
The Mixed Source Chinook Salmon Fishery In Lake Huron: A Comparison Of Spawning And Foraging Habitat Use By Naturalized And Hatchery Fish, Stephen A.C. Marklevitz
Electronic Thesis and Dissertation Repository
Chinook salmon (Oncorhynchus tshawytscha) were introduced into the Great Lakes to restore top-down control of the food web and create new recreational fisheries. Soon after introduction, naturalized spawning populations became established, and with continued stocking of hatchery fish, created a mixed source fishery. My research provides new ecological information about the contributions of naturalized fish to the mixed source Chinook salmon fishery in Lake Huron. I examined spawning and foraging habitat use by naturalized and hatchery Chinook salmon using multiple methods to identify sources of individual fish (external tags, hatchery fin clips, and otolith microchemistry). In the Sydenham …
Fear Of Predators Compromises Parental Care And Juvenile Survival In A Songbird, Philip Blair Dudeck
Fear Of Predators Compromises Parental Care And Juvenile Survival In A Songbird, Philip Blair Dudeck
Electronic Thesis and Dissertation Repository
Predators kill, but the risk of being killed is also a powerful force affecting survival because scared prey eat less, thereby increasing the likelihood of starvation. Young of most animals are extremely vulnerable to predators and may alter their behaviour to limit detection. I investigated the previously unexplored effects that predation risk has on the behaviour of newly fledged offspring and their parents, and the impact this has on offspring survival. I manipulated predation risk using sound and found that parent song sparrows reduced their feedings, providing 60% less food overall. Critically, not only did this parental response estimate survival …
Fish Out Of Salt Water: Smoltification In Subyearling Chinook Salmon From The Laurentian Great Lakes, Steve Sharron
Fish Out Of Salt Water: Smoltification In Subyearling Chinook Salmon From The Laurentian Great Lakes, Steve Sharron
Electronic Thesis and Dissertation Repository
The timing of smoltification in juvenile anadromous salmonids is important to ensure individuals match their preparedness with their migration timing and the optimal conditions in the environment. I performed the first study of smoltification in adfluvial juvenile Chinook salmon naturalized in the Laurentian Great Lakes. In a hatchery study, I found that juveniles from one of these populations have similar patterns of smoltification timing to individuals from anadromous populations. Their Na+/K+ ATPase activity, a common indicator or smolt status, peaked at 7.7 μmoles ADP/mg protein/hour on July 1 in freshwater. During the peak period, individual body size …
Ecological And Evolutionary Interactions Between Song Sparrows (Melospiza Melodia) And Their Bloodborne Parasites, Yanina Sarquis-Adamson
Ecological And Evolutionary Interactions Between Song Sparrows (Melospiza Melodia) And Their Bloodborne Parasites, Yanina Sarquis-Adamson
Electronic Thesis and Dissertation Repository
Local adaptation is the result of natural selection operating at a local scale, such that trade-offs in fitness across different environments result in individuals having higher fitness in their place of origin than when transported into a foreign environment. Populations may become locally adapted to features of their abiotic environment, or in the case of coevolutionary arms races between hosts and parasites, to other species comprising their biotic environment. If host populations are adapted to their local (sympatric) parasites, or conversely if parasites are adapted to their local hosts, then interactions with local parasite strains may influence the fitness consequences …
The Role Of Islands In The Migration Of Bats Across Lake Erie And Lake Ontario: Lasiurus Borealis, Lasiurus Cinereus And Perimyotis Subflavus, Toby J. Thorne
The Role Of Islands In The Migration Of Bats Across Lake Erie And Lake Ontario: Lasiurus Borealis, Lasiurus Cinereus And Perimyotis Subflavus, Toby J. Thorne
Electronic Thesis and Dissertation Repository
Large bodies of water, such as the Great Lakes in North America, are potential barriers to migrating bats. Islands may be used as stopover sites by bats crossing the Great Lakes as stopover sites, or included in crossing routes to reduce the distance flown over open water. I predicted that stopover use by migrating bats would result in higher activity on Great Lakes islands during late-season migration than at mainland sites. I monitored acoustic activity at 11 sites across four locations in Ontario: Amherst and Pelee islands, Kingston and Pinery Provincial Park during the summer (June and July), and during …
Low Temperature Tolerance Of Adult Drosophila Suzukii (Diptera: Drosophilidae), Ruth Jakobs
Low Temperature Tolerance Of Adult Drosophila Suzukii (Diptera: Drosophilidae), Ruth Jakobs
Electronic Thesis and Dissertation Repository
The crop pest Drosophila suzukii, native to Southeast Asia, has been found in Ontario since 2010. This raises concern with respect to it establishing permanent populations, however, little is known about its cold tolerance. I investigated the low-temperature tolerance, including phenotypic plasticity, of D. suzukii. While acclimation increased cold tolerance, there was no evidence of short-term cold-hardening. Chill coma occurs at -1.2 °C, which will limit winter activity. Cold shock decreased the reproductive output of females, but this negative effect may be mitigated by re-mating. Drosophila suzukii is chill-susceptible and 80 % of the flies die after exposure …
Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick
Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick
Electronic Thesis and Dissertation Repository
Increasing mercury (Hg) concentrations in top predatory fish is concerning for human and wildlife health. This study examined the amount of Hg available to the food web of Lake Erie, and explored the role that two recently established non-native species, dreissenid mussels and round goby, have played in the trophic transfer of Hg to sport fish. A comprehensive sampling of total Hg (THg) and methylmercury (MeHg) within Lake Erie water, sediment and seston with high temporal and spatial resolution describes environmental concentrations. In addition, biotic THg and MeHg are quantified in benthic invertebrates and three fish species. A steep spatial …