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Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti Jan 2024

Estimation Of Probability Of Habitat Use Of Roosevelt Elk On The Olympic Peninsula, Vincent Michael Gugliotti

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Estimating the probability of habitat use for a particular species is crucial to the direct management and conservation of that species. Without knowledge of habitat preferences, managers cannot effectively focus efforts on vital resources or landscape types. However, modelling probability of habitat use can be done in several ways which leaves room for variation and uncertainty in the estimates produced by each method. This study is an examination of the variation between two estimates of probability of habitat use while focusing on a particular subspecies of elk that inhabits a unique ecosystem relative to other elk subspecies. I modeled elk …


Conflicting Hydraulic Effects Of Xylem Pit Structure Relate To The Growth-Longevity Tradeoff In A Conifer Species, Beth Roskilly Jan 2018

Conflicting Hydraulic Effects Of Xylem Pit Structure Relate To The Growth-Longevity Tradeoff In A Conifer Species, Beth Roskilly

Graduate Student Theses, Dissertations, & Professional Papers

Consistent with a ubiquitous life history tradeoff, trees exhibit a negative relationship between growth and longevity among and within species. However, the mechanistic basis of this life history tradeoff is not well understood. In addition to tradeoffs among multiple traits based on resource allocation conflicts, life history tradeoffs may arise from tradeoffs based on single traits under opposing selection. While a myriad of factors likely contribute to the growth-longevity tradeoff in trees, we hypothesized that conflicting functional effects of xylem structural traits contribute to the growth-longevity tradeoff. We tested this hypothesis by examining the extent to which xylem morphological traits …


Reproductive Performance Of Kittlitz's Murrelet In A Glaciated Landscape, Icy Bay, Alaska, Usa, Michelle L. Kissling, Scott M. Gende, Stephen B. Lewis, Paul Lukacs Apr 2015

Reproductive Performance Of Kittlitz's Murrelet In A Glaciated Landscape, Icy Bay, Alaska, Usa, Michelle L. Kissling, Scott M. Gende, Stephen B. Lewis, Paul Lukacs

Wildlife Biology Faculty Publications

Kittlitz's Murrelet (Brachyramphus brevirostris) is a dispersed-nesting seabird endemic to Alaska and eastern Russia that may have experienced considerable population declines in some parts of its range in the past few decades. Poor reproduction has been suggested as the demographic bottleneck, yet there are no direct estimates of reproduction in a glaciated area where this species reaches its highest densities at sea during the breeding season. The lack of demographic information in glacial habitats has limited our ability to interpret population trends and to clarify whether the presence of glaciers affects reproductive performance. Between 2007 and 2012, we …


Wolf-Cougar Co-Occurrence In The Central Canadian Rocky Mountains, Ellen Brandell Jan 2015

Wolf-Cougar Co-Occurrence In The Central Canadian Rocky Mountains, Ellen Brandell

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Cougars and wolves are top carnivores that influence the dynamics of an ecosystem, including prey behavior and dynamics, and interspecific competition. Studies about the interactions between wolves and cougars typically find wolves are dominant competitors to cougars. We examined single-species, single-season occupancy models and co-occurrence models of wolves and cougars in the Central Canadian Rocky Mountains to understand interactions between these two species on a grand landscape. Data was collected from 2012-2013 using remote wildlife cameras and separated into seasons. Naïve occupancy estimates were larger for wolves in both seasons, but both species had smaller ranges in winter. There were …


Population Differentiation And Habitat Selection Of A Montane Red Fox Population In The Greater Yellowstone Ecosystem, Patrick Cross Jan 2015

Population Differentiation And Habitat Selection Of A Montane Red Fox Population In The Greater Yellowstone Ecosystem, Patrick Cross

Graduate Student Theses, Dissertations, & Professional Papers

Montane red fox (Vulpes vulpes) populations across the western United States are genetically and morphologically distinct from foxes at lower elevations. These montane populations also share a preference for subalpine forest habitats. One hypothesis is that they stem from boreal forest-associated ancestors that expanded during the Pleistocene when boreal forests extended farther south than they do today. Forest habitat selection may therefore aid the persistence of native populations surrounded by non-native conspecifics. Alternatively, this behavior may be an avoidance mechanism in response to competition with larger coyotes (Canis latrans), or a product of the fox's natural adaptability. The red fox …


The Importance Of Host Plant Limitation For Caterpillars Of An Arctiid Moth (Platyprepia Virginalis) Varies Spatially, Richard Karban, Patrick Grof-Tisza, John L. Maron, Marcel Holyoak Oct 2012

The Importance Of Host Plant Limitation For Caterpillars Of An Arctiid Moth (Platyprepia Virginalis) Varies Spatially, Richard Karban, Patrick Grof-Tisza, John L. Maron, Marcel Holyoak

Biological Sciences Faculty Publications

Spatial dynamic theories such as source–sink models frequently describe habitat-specific demographies, yet there are surprisingly few field studies that have examined how and why interacting species vary in their dynamics across multiple habitat types. We studied the spatial pattern of interaction between a chewing herbivore and its primary larval host plant in two habitat types. We found that the interaction between an arctiid caterpillar (Platyprepia virginalis) and its host (Lupinus arboreus) differed in wet vs. upland dry habitats, as did yearly population dynamics for the caterpillar. In upland sites, there was a strong positive relationship between …


The Forgotten Stage Of Forest Succession: Early-Successional Ecosystems On Forest Sites, Mark E. Swanson, Jerry F. Franklin, Robert L. Beschta, Charles M. Crisafulli, Dominick A. Dellasala, Richard L. Hutto, David B. Lindenmaver, Frederick J. Swanson Mar 2011

The Forgotten Stage Of Forest Succession: Early-Successional Ecosystems On Forest Sites, Mark E. Swanson, Jerry F. Franklin, Robert L. Beschta, Charles M. Crisafulli, Dominick A. Dellasala, Richard L. Hutto, David B. Lindenmaver, Frederick J. Swanson

Biological Sciences Faculty Publications

Early-successional forest ecosystems that develop after stand-replacing or partial disturbances are diverse in species, processes, and structure. Post-disturbance ecosystems are also often rich in biological legacies, including surviving organisms and organically derived structures, such as woody debris. These legacies and post-disturbance plant communities provide resources that attract and sustain high species diversity, including numerous early-successional obligates, such as certain woodpeckers and arthropods. Early succession is the only period when tree canopies do not dominate the forest site, and so this stage can be characterized by high productivity of plant species (including herbs and shrubs), complex food webs, large nutrient fluxes, …


Correlation And Studies Of Habitat Selection: Problem, Red Herring Or Opportunity?, John Fieberg, Jason Matthiopoulos, Mark Hebblewhite, Mark S. Boyce, Jacqueline L. Frair Jun 2010

Correlation And Studies Of Habitat Selection: Problem, Red Herring Or Opportunity?, John Fieberg, Jason Matthiopoulos, Mark Hebblewhite, Mark S. Boyce, Jacqueline L. Frair

Biological Sciences Faculty Publications

With the advent of new technologies, animal locations are being collected at ever finer spatio-temporal scales. We review analytical methods for dealing with correlated data in the context of resource selection, including post hoc variance inflation techniques, ‘two-stage’ approaches based on models fit to each individual, generalized estimating equations and hierarchical mixed-effects models. These methods are applicable to a wide range of correlated data problems, but can be difficult to apply and remain especially challenging for use–availability sampling designs because the correlation structure for combinations of used and available points are not likely to follow common parametric forms. We also …


Distinguishing Technology From Biology: A Critical Review Of The Use Of Gps Telemetry Data In Ecology, Mark Hebblewhite, Daniel T. Haydon Jun 2010

Distinguishing Technology From Biology: A Critical Review Of The Use Of Gps Telemetry Data In Ecology, Mark Hebblewhite, Daniel T. Haydon

Biological Sciences Faculty Publications

In the past decade, ecologists have witnessed vast improvements in our ability to collect animal movement data through animal-borne technology, such as through GPS or ARGOS systems. However, more data does not necessarily yield greater knowledge in understanding animal ecology and conservation. In this paper, we provide a review of the major benefits, problems and potential misuses of GPS/Argos technology to animal ecology and conservation. Benefits are obvious, and include the ability to collect fine-scale spatio-temporal location data on many previously impossible to study animals, such as ocean-going fish, migratory songbirds and long-distance migratory mammals. These benefits come with significant …


Are Forested Buffers An Effective Conservation Strategy For Riparian Fauna? An Assessment Using Meta-Analysis, Laurie B. Marczak, Takashi Sakamaki, Shannon L. Turvey, Isabelle Deguise, Sylvia L. R. Wood, John S. Richardson Jan 2010

Are Forested Buffers An Effective Conservation Strategy For Riparian Fauna? An Assessment Using Meta-Analysis, Laurie B. Marczak, Takashi Sakamaki, Shannon L. Turvey, Isabelle Deguise, Sylvia L. R. Wood, John S. Richardson

Biological Sciences Faculty Publications

Historically, forested riparian buffers have been created to provide protection for aquatic organisms and aquatic ecosystem functions. Increasingly, new and existing riparian buffers are being used also to meet terrestrial conservation requirements. To test the effectiveness of riparian buffers for conserving terrestrial fauna, we conducted a meta-analysis using published data from 397 comparisons of species abundance in riparian buffers and unharvested (reference) riparian sites. The response of terrestrial species to riparian buffers was not consistent between taxonomic groups; bird and arthropod abundances were significantly greater in buffers relative to unharvested areas, whereas amphibian abundance decreased. Edge-preferring species were more abundant …


Ecological Facilitation May Drive Major Evolutionary Transitions, Zaal Kikvidze, Ragan M. Callaway May 2009

Ecological Facilitation May Drive Major Evolutionary Transitions, Zaal Kikvidze, Ragan M. Callaway

Biological Sciences Faculty Publications

There is a growing consensus among ecologists that ecological facilitation comprises a historically overlooked but crucial suite of biotic interactions. Awareness of such positive interactions has recently led to substantial modifications in ecological theory. In this article we suggest how facilitation may be included in evolutionary theory. Natural selection based on competition provides a conceptually complete paradigm for speciation, but not for major evolutionary transitions-the emergence of new and more complex biological structures such as cells, organisms, and eusocial populations. We find that the successful theories developed to solve these specific problematic transitions show a consistent pattern: they focus on …


Filling Key Gaps In Population And Community Ecology, Anurag A. Agrawal, David D. Ackerly, Fred Adler, A. Elizabeth Arnold, Carla Cáceres, Daniel F. Doak, Eric Post, Peter J. Hudson, John L. Maron, Kailen A. Mooney, Mary Power, Doug Schemske, Jay Stachowicz, Sharon Strauss, Monica G. Turner, Earl Werner Apr 2007

Filling Key Gaps In Population And Community Ecology, Anurag A. Agrawal, David D. Ackerly, Fred Adler, A. Elizabeth Arnold, Carla Cáceres, Daniel F. Doak, Eric Post, Peter J. Hudson, John L. Maron, Kailen A. Mooney, Mary Power, Doug Schemske, Jay Stachowicz, Sharon Strauss, Monica G. Turner, Earl Werner

Biological Sciences Faculty Publications

We propose research to fill key gaps in the areas of population and community ecology, based on a National Science Foundation workshop identifying funding priorities for the next 5–10 years. Our vision for the near future of ecology focuses on three core areas: predicting the strength and context-dependence of species interactions across multiple scales; identifying the importance of feedbacks from individual interactions to ecosystem dynamics; and linking pattern with process to understand species coexistence. We outline a combination of theory development and explicit, realistic tests of hypotheses needed to advance population and community ecology.


Is Selectively Harvested Forest An Ecological Trap For Olive-Sided Flycatchers?, Bruce A. Robertson, Richard L. Hutto Feb 2007

Is Selectively Harvested Forest An Ecological Trap For Olive-Sided Flycatchers?, Bruce A. Robertson, Richard L. Hutto

Biological Sciences Faculty Publications

Disturbance-dependent species are assumed to benefit from forestry practices that mimic the appearance of postdisturbance landscapes. However, human activities that closely mimic the appearance but not the fundamental quality of natural habitats could attract animals to settle whether or not these habitats are suitable for their survival or reproduction. We examined habitat selection behavior and nest success of Olive-sided Flycatchers (Contopus cooperi) in a naturally occurring burned forest and an anthropogenically created habitat type-selectively harvested forest. Olive-sided Flycatcher density and nestling provisioning rates were greater in the selectively harvested landscape, whereas estimated nest success in selectively harvested forest was roughly …


Linking Scales In Stream Ecology, Winsor H. Lowe, Gene E. Likens, Mary E. Power Jul 2006

Linking Scales In Stream Ecology, Winsor H. Lowe, Gene E. Likens, Mary E. Power

Biological Sciences Faculty Publications

The hierarchical structure of natural systems can be useful in designing ecological studies that are informative at multiple spatial scales. Although stream systems have long been recognized as having a hierarchical spatial structure, there is a need for more empirical research that exploits this structure to generate an understanding of population biology, community ecology, and species-ecosystem linkages across spatial scales. We review studies that link pattern and process across multiple scales of stream-habitat organization, highlighting the insight derived from this multiscale approach and the role that mechanistic hypotheses play in its successful application. We also describe afrontier in stream research …


A Framework For Understanding Ecological Traps And An Evaluation Of Existing Evidence, Bruce A. Robertson, Richard L. Hutto May 2006

A Framework For Understanding Ecological Traps And An Evaluation Of Existing Evidence, Bruce A. Robertson, Richard L. Hutto

Biological Sciences Faculty Publications

When an animal settles preferentially in a habitat within which it does poorly relative to other available habitats, it is said to have been caught in an “ecological trap.” Although the theoretical possibility that animals may be so trapped is widely recognized, the absence of a clear mechanistic understanding of what constitutes a trap means that much of the literature cited as support for the idea may be weak, at best. Here, we develop a conceptual model to explain how an ecological trap might work, outline the specific criteria that are necessary for demonstrating the existence of an ecological trap, …


The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors May 2000

The Impacts Of A Nonindigenous Marine Predator In A California Bay, Edwin D. Grosholz, Gregory M. Ruiz, Cheryl A. Dean, Kim A. Shirley, John L. Maron, Peter G. Connors

Biological Sciences Faculty Publications

Coastal marine ecosystems worldwide are being altered rapidly by the invasion of nonindigenous species. Unlike terrestrial and freshwater systems, the impacts of an invading species have never been quantified on multiple trophic levels for a marine food web. We measured the impact of the nonindigenous green crab, Carcinus maenas, on a coastal marine food web in central California and found that this predator exerted strong “top-down” control, significantly reducing the abundances of several of the 20 invertebrate species monitored over a 9-yr period. Densities of native clams, Nutricola tantilla and Nutricola confusa, and native shore crabs, Hemigrapsus oregonensis, showed 5-fold …


Impact Of A Parasitic Plant On The Structure And Dynamics Of Salt Marsh Vegetation, Steven C. Pennings, Ragan M. Callaway Jul 1996

Impact Of A Parasitic Plant On The Structure And Dynamics Of Salt Marsh Vegetation, Steven C. Pennings, Ragan M. Callaway

Biological Sciences Faculty Publications

We investigated the effect of a native parasitic plant, Cuscuta salina, on the structure and dynamics of the plant community in a California salt marsh. Cuscuta was common in the middle marsh zones. The abundance of Cuscuta was positively correlated with the abundance of Limonium californicum at two sampling scales (0.25— and ≈\approx40—m2 quadrats). Sampling at the scale of individual plants indicated that the dominant plant in the marsh, Salicornia virginica, was preferred by Cuscuta as a host over Arthrocnemum subterminale, Limonium californicum, and Frankenia salina. This result was confirmed with host—choice experiments in the field. Based on spatial …


Temperature-Driven Variation In Substrate Oxygenation And The Balance Of Competition And Facilitation, Ragan M. Callaway, Leah King Jun 1996

Temperature-Driven Variation In Substrate Oxygenation And The Balance Of Competition And Facilitation, Ragan M. Callaway, Leah King

Biological Sciences Faculty Publications

Emergent wetland plants often alleviate the effects of anaerobic soils on root respiration by passively transporting oxygen belowground through continuous air spaces (aerenchyma) in leaves and roots. Oxygen leaked from the roots into the rhizosphere may oxidize minerals in the soil or become available to other plants. Some spatial patterns in marsh plant communities suggest interspecific facilitative interactions, but there is little experimental evidence for interplant facilitation via soil oxygenation. We investigated the capability of the widespread, highly aerenchymous wetland plant, Typa latifolia, to aerate sediments and affect the growth of two non—aerenchymous neighbors, Salix exigua and Myosotis laxa, both …


Use Of Gene Probes To Aid In Recovery And Identification Of Functionally Dominant 2,4-Dichlorophenoxyacetic Acid-Degrading Populations In Soil, J. O. Ka, William E. Holben, James M. Tiedje Apr 1994

Use Of Gene Probes To Aid In Recovery And Identification Of Functionally Dominant 2,4-Dichlorophenoxyacetic Acid-Degrading Populations In Soil, J. O. Ka, William E. Holben, James M. Tiedje

Biological Sciences Faculty Publications

The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) was applied to soils in microcosms, and degradation was monitored after each of five repeated additions. Total DNAs were isolated from soil bacterial communities after each 2,4-D treatment. The DNA samples were analyzed on slot blots and Southern blots by using a tfdA gene probe subcloned from plasmid pJP4 and a Spa probe derived from a different 2,4-D-degrading isolate, a Sphingomonas paucimobilis strain. 2,4-D applied to soil was quickly degraded by indigenous microbial populations. As determined by slot blot analyses of DNA from a Michigan soil, the increase in hybridization signal in response to 2,4-D …


Dna Probe Method For The Detection Of Specific Microorganisms In The Soil Bacterial Community, William Holben, Janet K. Jansson, Barry K. Chelm, James M. Tiedje Mar 1988

Dna Probe Method For The Detection Of Specific Microorganisms In The Soil Bacterial Community, William Holben, Janet K. Jansson, Barry K. Chelm, James M. Tiedje

Biological Sciences Faculty Publications

We developed a protocol which yields purified bacterial DNA from the soil bacterial community. The bacteria were first dispersed and separated from soil particles in the presence of polyvinylpolypyrrolidone, which removes humic acid contaminants by adsorption to this insoluble polymer. The soil bacteria were then collected by centrifugation and lysed by using a comprehensive protocol designed to maximize disruption of the various types of bacteria present. Total bacterial DNA was purified from the cell lysate and remaining soil contaminants by using equilibrium density gradients. The isolated DNA was essentially pure as determined by UV spectral analysis, was at least 48 …