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Community Composition And Biogeography Of Beetles And Spiders Across An Elevational Gradient In Denali National Park, Alaska, Adam Haberski

Biological Sciences

Anthropogenic climate change is rapidly altering alpine ecosystems in Alaska. Trees and woody shrubs are expanding upslope and displacing alpine tundra. As alpine tundra habitats shrink and fragment, arthropods and other animals face an increased risk of extirpation due to smaller population sizes and reduced geneflow. Arthropods--insects, spiders, and their relatives--are the most speciose component of the alpine fauna and perform key ecosystem services, such as pollination and nutrient cycling, and are food for vertebrates. Many species have responded by shifting their distribution to higher elevations, but species respond to change idiosyncratically, which could alter species interactions and disrupt communities. …

Science, Perception And Scale: An Interdisciplinary Analysis Of Environmental Change And Community Adaptive Capaciy, Jesse E. Grunblatt

Biological Sciences

The discrepancy between science-based assessments of climate change and public acknowledgement of climate change has been extensively documented at a national level. The relationship of science-based assessments and public awareness of environmental change at the local community level is less studied. An understanding of how science-based information informs local perception is important to ensure that science communication effectively supports community decision making. This dissertation explores the gap between science-based assessments and local perception of environmental change within a framework of adaptive capacity. The research is divided into three interrelated studies that provide: 1) an assessment of community perception of local …

Demographics And Telomere Dynamics Of Hibernating Arctic Ground Squirrels (Urocitellus Parryii), Sara M. Wilbur

Biological Sciences

Aging is the complex process by which an organism loses functional integrity over time. Several measurable contributors to or components of the aging process have been identified, one of which is telomere length. Telomeres are the repetitive, nucleoprotein structures located at the ends of linear chromosomes. In general, telomeres shorten over time and when exposed to damaging reactive oxygen species (highly unstable molecules released as a byproduct of cellular respiration). Organisms that have unique physiologies, in addition to those that live longer than otherwise predicted, have recently inspired comparative telomere dynamics studies. Hibernating mammals, which exhibit both heterothermy and long …

Influence Of Soil Water Content And Soil Amendments On Trace Metal Release And Seedling Growth In Serpentine Soil, Viraj Gunarathne, Nishanta Rajakaruna, Udaya Gunarathne, Jayanta Kumar Biswas, Zach A. Raposo, Meththika Vithanage

Biological Sciences

This study was conducted to evaluate the synergistic effects of organic amendments and soil water status on trace metal release from serpentine soil.

Do Wintering Conditions Drive Population Trends In Semipalmated Sandpipers (Calidris Pusilla)? Evidence From A Corticosterone Biomarker, Megan L. Boldenow

Biological Sciences

Some of the most extreme long-distance migrants, Arctic-breeding shorebirds are disproportionately represented in tallies of declining species worldwide. For many shorebirds, including the semipalmated sandpiper (Calidris pusilla), the specific causes and mechanisms behind population declines have not been identified. Stressful conditions affecting birds during wintering are often implicated. Interactions between events and processes occurring in the disparate locations used throughout the annual cycle also may be critical in shaping both individual life histories and population demographics. The main objectives of my graduate research were: a) to examine whether semipalmated sandpipers wintering in specific locations incur differential levels of stress; and …

Optimizing Landbird Surveys For Detecting Population And Spatial Dynamics, Jeremy D. Mizel

Biological Sciences

Landbird populations are undergoing concurrent changes in population size, spatial distribution, and phenology. The sensitivity of landbird monitoring programs to detect and distinguish these varied processes is of critical importance. Consequently, these efforts require inference methods that are efficient and fully leverage information about spatial, population, and phenological dynamics. The development of efficient inference methods can be addressed in part through a thorough understanding of how the data are actually generated, the application of sampling methods that attempt to maximize encounter probability, and the tailoring of sampling methods to maximize sensitivity to specific inference objectives. Chapter one of this dissertation …

An Ecological-Physiology Perspective On Seabird Responses To Contemporary And Historic Environmental Change, Alexis P. Will

Biological Sciences

The chapters included in this dissertation implement an ecological-physiology approach to understanding how long-lived marine organisms, using seabirds as a model, respond to changes in the environment. Many seabird populations are governed by bottom-up processes, yet efforts to connect prey dynamics and parameters such as breeding performance often yield mixed results. Here I examined how individual foraging behavior and nutritional status change at the inter-annual, decadal, and multi-decadal scale. I validated that the concentration of the avian stress hormone in seabird feathers is indicative of their exposure to nutritional stress. I then used this technique to show that young seabirds …

Ultramafic Geoecology Of South And Southeast Asia, M.L. Galey, A. Van Der Ent, M.C.M. Iqbal, N. Rajakaruna

Biological Sciences

Globally, ultramafic outcrops are renowned for hosting foras with high levels of endemism, including plants with specialised adaptations such as nickel or manganese hyperaccumulation. Soils derived from ultramafic regoliths are generally nutrient-deficient, have major cation imbalances, and have concomitant high concentrations of potentially phytotoxic trace elements, especially nickel. The South and Southeast Asian region has the largest surface occurrences of ultramafic regoliths in the world, but the geoecology of these outcrops is still poorly studied despite severe conservation threats. Due to the paucity of systematic plant collections in many areas and the lack of georeferenced herbarium records and databased information, …

The Alpine Vascular Plants Of Baxter State Park, Maine, Usa, Abigail J. Urban, Glen H. Mittelhauser, Matthew Dickinson, N. Rajakaruna

Biological Sciences

We conducted 12 days of field surveys on five mountains over 1100 m in elevation (Katahdin, North Brother, South Brother, Mount Coe, and The Owl) in Baxter State Park (BSP), Maine during the summers of 2013–14. In addition, we examined historic manuscripts, unpublished data, and herbarium records for plant records from the five mountains. Katahdin, the largest and tallest of the five mountains, has a rich history of botanical exploration and we documented 1559 herbarium vouchers that were collected from the mountain, primarily before the mid-1900s. Combining all data sources, we documented 38 families, 87 genera, and 131 taxa of …

Breeding Ecology Of Whimbrels (Numenius Phaeopus) In Interior Alaska, Christopher M. Harwood

Biological Sciences

Whimbrels Numenius phaeopus breed in tundra-like habitats, both beyond treeline and within the boreal forest of interior Alaska. Despite their widespread distribution and designation as a species of conservation concern, their ecology has been particularly understudied in Alaska. During 2008--2012, I initiated the first dedicated study of Whimbrel breeding ecology in Alaska, and the first such study of any boreal-breeding shorebird in the state. Within a habitat mosaic of forest, woodlands, muskeg, scrub, and ponds within the floodplain of the Kanuti River in north-central Alaska, Whimbrels bred in the three largest (of nine) patches of discontinuous tussock tundra. These Whimbrels …

A Comparative Study Of The Flora And Soils Of Great Duck And Little Duck Islands, Maine, Usa, Luka Negoita, Matthew Dickinson, Glen H. Mittlehauser, N. Rajakaruna

Biological Sciences

Strong environmental gradients and varied land-use practices have generated a mosaic of habitats harboring distinct plant communities on islands on the coast of Maine. Botanical studies of Maine’s islands, however, are generally limited in number and scope. Baseline studies of Maine’s islands are necessary for assessing vegetation dynamics and changes in habitat conditions in relation to environmental impacts imposed by climate change, rising sea levels, invasive species, pests and pathogens, introduced herbivores, and human disturbance. We conducted a survey of the vascular plants and soils of forest, field, and ocean-side communities of Great Duck and Little Duck Islands, ME. These …

Trophic Pathways Supporting Juvenile Chinook And Coho Salmon In The Glacial Susitna River, Alaska: Patterns Of Freshwater, Terrestrial, And Marine Resource Use Across A Seasonally Dynamic Habitat Mosaic, Kristin M. Rine

Biological Sciences

In large, seasonally dynamic and spatially complex watersheds, the availability and relative importance of various food resources for stream fishes can be expected to vary substantially. While numerous studies have attempted to uncover the trophic linkages that support stream salmonids, much of these efforts have occurred at small scales that disregard variability of food resources inherent in lotic systems. This study aimed to determine large-scale patterns in the contributions of freshwater, terrestrial, and marine-derived food resources to juvenile Chinook and Coho salmon (Oncorhynchus tshawytscha and O. kisutch) in the large, glacially influenced Susitna River, Alaska. I quantified diet patterns both …

Alpine Thermal Dynamics And Associated Constraints On The Behavior Of Mountain Goats In Southeast Alaska, Jeffrey HéBert Frederick

Biological Sciences

Alpine Caprinae, including mountain goats (Oreamnos americanus), have been described to be sensitive to temperature changes within their summer range and consequently may be forced to select habitats that allow for the maintenance of a stable core temperature on warm days. Survival may be inhibited if warm ambient temperatures cause mountain goats to reduce time foraging or if too much time is spent on thermoregulatory habitat selection. I investigated mountain goat behavioral activity budgets across alpine temperature gradients in Southeast Alaska using focal animal sampling and scan sampling techniques. I tested the effects of temperature on mountain goat activity and …

Effects Of Harvest On Wolf Social Structure, Population Dynamics, And Viewing Opportunities In National Parks, Bridget Borg

Biological Sciences

Management of gray wolves (Canis lupus) in and adjacent to Denali National Park and Preserve (DNPP) is complex. Wolves that live primarily within the park, where they are protected from harvest, often range across the boundary of the park where harvest of wolves is legal. Protection of wolves within the park provides for wolf viewing opportunities along the Denali Park Road for tens of thousands of visitors annually. Additionally, there is interest in maintaining wolf harvest opportunities adjacent to the park. The objectives for wolf viewing and harvest have been perceived as in direct conflict, but quantitative analysis of the …

Trophic Pathways Supporting Arctic Grayling In A Small Stream On The Arctic Coastal Plain, Alaska, Jason John Mcfarland

Biological Sciences

Arctic Grayling (Thymallus arcticus) are widely distributed on the Arctic Coastal Plain (ACP) of Alaska, and are one of the few upper level consumers in streams, but the trophic pathways and food resources supporting these fish are unknown. Grayling migrate each summer into small beaded streams, which are common across the landscape on the ACP, and appear to be crucial foraging grounds for these and other fishes. I investigated prey resources supporting different size classes of grayling in a beaded stream, Crea Creek, where petroleum development is being planned. The specific objectives were to measure terrestrial prey subsidies entering the …

Global Research On Ultramafic (Serpentine) Ecosystems (8th International Conference On Serpentine Ecology In Sabah, Malaysia): A Summary And Synthesis, Antony Van Der Ent, Nishanta Rajakaruna, Robert Boyd, Guillaume Echevarria, Rimi Repin, Dick Williams

Biological Sciences

Since 1991, researchers from approximately 45 nations have participated in eight International Conferences on Serpentine Ecology (ICSE). The Conferences are coordinated by the International Serpentine Ecology Society (ISES), a formal research society whose members study geological, pedological, biological and applied aspects of ultramafic (serpentine) ecosystems worldwide. These conferences have provided an international forum to discuss and synthesise multidisciplinary research, and have provided opportunities for scientists in distinct fields and from different regions of the world to conduct collaborative and interdisciplinary research. The 8th ICSE was hosted by Sabah Parks in Malaysia, on the island of Borneo, and attracted the largest …

Growth And Nickel Uptake By Serpentine And Non-Serpentine Populations Of Fimbristylis Ovata (Cyperaceae) From Sri Lanka, P. K. D. Chathuranga, S. K. A. T. Dharmasena, Nishanta Rajakaruna, M.C.M. Iqbal

Biological Sciences

Compared with serpentine floras of Southeast Asia, the serpentine vegetation of Sri Lanka is impoverished in regard to serpentine endemics and nickel hyperaccumulators. All species so far documented from the serpentine outcrops of Sri Lanka also have non-serpentine populations; it is unclear whether the serpentine populations are physiologically distinct and deserve ecotypic recognition. We conducted a preliminary study to examine whether serpentine and non-serpentine populations of Fimbristylis ovata represent locally adapted ecotypes by investigating their growth and potential for nickel uptake and tolerance under greenhouse conditions. Although both populations of F. ovata showed a similar growth pattern in serpentine soil …

Water, Behavior, And Health In Alaska, Troy L. Ritter

Biological Sciences

This dissertation addresses the need for a better understanding of how water and sanitation infrastructure and water use behaviors come together to influence health. The ultimate aim is to inform water infrastructure designs and behavior change programming for the prevention of acute respiratory infections (ARIs), skin infections, and diarrhea. All three diseases are of public health significance in Alaska, and all three can be prevented by proper access and use of water and sanitation services. I begin the dissertation by illustrating that some residents who have access to treated water continue to consume untreated river water and rain. In fact, …

Behavior, Physiology, Biological Age, And Cultural Role Of Long-Lived Bering Sea Seabirds, Rebecca C. Young

Biological Sciences

This dissertation focuses on the intersection of behavior, physiology, and biological age. Biological age is a measure of an organism's progress through life, and it incorporates chronological age as well as the actions of environment and innate quality at the individual level. We estimate biological age using telomere length as a biomarker. Telomere degradation in relation to oxidative stress links it directly to purported proximate mechanisms of aging under the free radical theory of aging. Short telomeres, or telomere loss, have been related to ecological indicators of lowered fitness. Our work focuses on aging in the thick-billed murre (Uria lomvia), …

Spatial Variability In Plant And Soil Properties On New Zealand Seabird Islands, And The Effects Of Introduced Rats, Melody S. Durrett

Biological Sciences

Seabirds are ecosystem engineers with two major impacts on island ecosystems: they bring large quantities of marine nutrients to the terrestrial environment in the form of guano, carcasses, feathers, eggs, and spilled food, and they disturb the soil surface. Burrowing seabirds can denude the soil surface of all seedlings and leaf litter, plowing them under and loosening the soil. However, seabirds are colonial, and burrows are not evenly spaced over the surface of an island, producing spatial variability within a single island that might reveal how seabird activities control island ecosystem function. In this dissertation I review seabird island ecology …

The Role Of Elevation And Soil Chemistry In The Distribution And Ion Accumulation Of Floral Morphs Of Streptanthus Polygaloides Gray (Brassicaceae), A Californian Nickel Hyperaccumulator, Nathaniel S. Pope, Michael Fong, Robert S. Boyd, Nishanta Rajakaruna

Biological Sciences

Background: The flora of serpentine/ultramafic soils provides an excellent model system for the study of natural selection in plant populations. Streptanthus polygaloides is a nickel hyperaccumulator that is endemic to serpentine soils in the Sierra Nevada of California, and has four floral morphs (yellow, purple, yellow-to-purple and undulate).

Aims: We investigate three hypotheses: (1) the purple morph occurs in colder, wetter climates than the yellow morph; (2) tissue–soil ionic relationships differ among morphs; and (3) morphs occur on soils with differing elemental concentrations.

Methods: We queried herbarium records to investigate patterns of occurrence among the yellow and purple floral morphs, …

The Distribution And Habitat Use Of North Dakota Bats, Paul Roy Barnhart

Biological Sciences

Prior to 2009, a comprehensive statewide survey of occurrence and distribution of bats in North Dakota had not been conducted. From 2009 to 2012, mist netting, radio telemetry, and acoustic monitoring were conducted to document species presence and habitat associations across North Dakota. We surveyed multiple sites at 17 locations, captured a total of 309 bats, documented habitat associations, and identified roosting sites. Data was then used to: 1) build habitat suitability maps (also called species distribution maps or SDMs) for each species in the state, 2) examine the environmental and climatic variables that influence bat habitat use along the …

Epizootic Of Beak Deformities In Alaska: Investigation Of An Emerging Avian Disease, Caroline Van Hemert

Biological Sciences

The sudden appearance of morphological abnormalities in a wild population is often associated with underlying ecological disturbances, including those related to introduction of new pathogens or pollutants. An epizootic of beak deformities recently documented among Black-capped Chickadees (Poecile atricapillus) and other resident bird species in Alaska has raised concern about underlying causes. This dissertation describes results from several recent studies of what we have termed "avian keratin disorder." The primary objectives of the research were to characterize the physiology and pathology of beak deformities and to address specific ecological questions related to this emerging avian disease. In a study of …

Experimentally Altered Navigational Demands Induce Changes In The Cortical Forebrain Of Free-Ranging Northern Pacific Rattlesnakes (Crotalus O. Oreganus), Matthew L. Holding, Julius A. Frazier, Emily N. Taylor, Christine R. Strand

Biological Sciences

The hippocampus of birds and mammals plays a crucial role in spatial memory and navigation. The hippocampus exhibits plasticity in adulthood in response to diverse environmental factors associated with spatial demands placed on an animal. The medial and dorsal cortices of the telencephalon of squamate reptiles have been implicated as functional homologues to the hippocampus. This study sought to experimentally manipulate the navigational demands placed on free-ranging northern Pacific rattlesnakes (Crotalus o. oreganus) to provide direct evidence of the relationship between spatial demands and neuroplasticity in the cortical telencephalon of the squamate brain. Adult male rattlesnakes were radio-tracked for 2 …

Novel Fungal Taxa In An Alaskan Boreal Forest: Phylogenetic Affinities, Ecologies, And Ribosomal Rna Secondary Structures, Daniel Glass

Biological Sciences

Phylogenetic analyses suggest that a novel DNA sequence (NS1) found in a boreal forest soil-clone library belongs to the fungal kingdom but does not fall unambiguously within any known class. In order to determine if NS1 codes for an authentic ribosomal RNA (rRNA) gene-copy, I modeled ribosomal RNA secondary structure for four gene regions. Such analyses have never been used on environmental ribosomal sequences before. It appears that NS1 does code for an authentic gene-copy and is not a biological or lab artifact. I also elucidated the habitat preferences, horizon preferences, and fine-scale spatial structure of NS1 using molecular methods. …

Addressing Biased Occurrence Data In Predicting Potential Sierra Nevada Red Fox Habitat For Survey Prioritization, Casey Cleve, John D. Perrine, Barbara Holzman, Ellen Hines

Biological Sciences

The Sierra Nevada red fox Vulpes vulpes necator is listed as a threatened species under the California Endangered Species Act. It originally occurred throughout California’s Cascade and Sierra Nevada mountain regions. Its current distribution is unknown but should be determined in order to guide management actions. We used occurrence data from the only known population, in the Lassen Peak region of northern California, combined with climatic and remotely sensed variables, to predict the species’ potential distribution throughout its historic range. These model predictions can guide future surveys to locate additional fox populations. Moreover, they allow us to compare the relative …

Survival Of Duck Nests, Distribution Of Duck Broods, And Habitat Conservation Targeting In The Prairie Pothole Region, Johann Walker

Biological Sciences

The Prairie Pothole Region (PPR) is an important breeding region for populations of upland-nesting ducks (Anas spp.). I studied survival of duck nests, distribution of duck broods, and conservation easement targeting in the PPR of North and South Dakota, USA. Nest survival of common duck species varied from 0.02 (ŜE = 0.01) to 0.23 (ŜE = 0.02) among study sites and years and was positively related to current pond density and primary productivity and negatively related to recent pond density and primary productivity. This result was consistent with the hypothesis that nest predators and thus nest survival were responding to …

Arctic Alaskan Shrub Growth, Distribution, And Relationships To Landscape Processes And Climate During The 20th Century, Ken D. Tape

Biological Sciences

The primary change underway in the tundra of Arctic Alaska is the increase in air temperature and expansion of deciduous shrubs since 1980. I explored relationships between shrub expansion and relevant ecosystem properties such as climate, soil characteristics, erosion, and herbivory. Alnus viridis ssp. fruticosa (Siberian alder) shrubs located along streams, rock outcrops, or other features with active disturbance regimes showed a positive correlation between growth ring widths and March through July air temperature. Climate-growth relationships were much weaker for alder in adjacent tussock tundra. Additionally, tussock tundra sites had different vegetation composition, shallower thaw, lower mean annual ground temperature, …

The Evaluation Of Christmas Bird Counts As An Indicator Of Population Trends And Habitat Selection In Blackbirds And Starlings, Matthew D. Strassburg

Biological Sciences

Agelaius phoeniceus (red-winged blackbird), Quiscalus quiscula (common grackle), and Sturnus vulgaris (European starling) are three of the most abundant bird species found in North America, and along with Euphagus carolinus (rusty blackbird) and Euphagus cyanocephalus (Brewer’s blackbird), make up a significant proportion of the avian population. Population trends of these four blackbird species and European starlings (EUST)were analyzed from the Christmas Bird Count (CBC) data collected between 1988 and 2008. Population analyses were conducted using linear mixed-effect regressions from the Lmer package of Program R. This approach was effective in modeling the population trends of widespread species with large populations. …

Sierra Nevada Red Fox (Vulpes Vulpes Necator): A Conservation Assessment, John D. Perrine, Lori A. Campbell, Gregory A. Green

Biological Sciences

One goal of the Sierra Nevada Forest Plan Amendment (SNFPA) 2001 and 2004 Records of Decision was to protect and recover native Sierra Nevada red fox (Vulpes vulpes necator) populations in the Sierra Nevada (USDA Forest Service 2001 p. 14). To accomplish this goal, the ROD commits the U.S. Department of Agriculture (USDA) Forest Service to completing a conservation assessment for the Sierra Nevada red fox in cooperation with other federal, state, and local agencies, as well as Tribal governments. This conservation assessment synthesizes the best available scientific information and thought concerning habitat relationships, population status and trends, historical and …