Ecology and Evolutionary Biology Commons^™

Spatiotemporal Patterns Of Chlorophyll-A Concentration In A Hypersaline Lake Using High Temporal Resolution Remotely Sensed Imagery, R. Douglas Ramsey, Soren M. Brothers, Melissa Cobo, Wayne A. Wurtsbaugh

Wildland Resources Faculty Publications

The Great Salt Lake (GSL) is the largest saline lake in the Western Hemisphere. It supports billion-dollar industries and recreational activities, and is a vital stopping point for migratory birds. However, little is known about the spatiotemporal variation of phytoplankton biomass in the lake that supports these resources. Spectral reflectance provided by three remote sensing products was compared relative to their relationship with field measurements of chlorophyll a (Chl a). The MODIS product MCD43A4 with a 500 m spatial resolution provided the best overall ability to map the daily distribution of Chl a. The imagery indicated significant spatial …

Timber Harvesting Was The Most Important Factor Driving Changes In Vegetation Composition, As Compared To Climate And Fire Regime Shifts, In The Mixedwood Temperate Forests Of Temiscamingue Since Ad 1830, Daniela Robles, Yan Boulanger, Jesus Pascual, Victor Danneyrolles, Yves Bergeron, Igor Drobyshev

Aspen Bibliography

Context The vegetation composition of northeastern North American forests has significantly changed since pre-settlement times, with a marked reduction in conifer-dominated stands, taxonomic and functional diversity. These changes have been attributed to fire regime shifts, logging, and climate change.

Methods In this study, we disentangled the individual effects of these drivers on the forest composition in southwestern Quebec from 1830 to 2000 by conducting retrospective modelling using the LANDIS-II forest landscape model. The model was run based on pre-settlement forest composition and fire history reconstructions, historical timber harvest records, and climate reanalysis data. We compared counterfactual scenarios excluding individual factors …

Evaluating Elk Distribution And Conflict Under Proposed Management Alternatives At The National Elk Refuge In Jackson, Wyoming, Gavin G. Cotterill, Paul C. Cross, Eric K. Cole, Jonathan D. Cook, Margaret C. Mceachran, Tabitha A. Graves

Aspen Bibliography

We evaluated measurable attributes describing the current and future distribution of Cervus elaphus canadensis (elk) across a region surrounding Jackson, Wyoming, for five feedground management alternatives proposed by the U.S. Fish and Wildlife Service as a revision to 2007 "Bison and Elk Management Plan" of the National Elk Refuge. A resource selection function evaluated measurable attributes of interest to managers, including elk use of private property and sensitive habitat types at monthly timesteps and varying winter conditions. The study area boundaries were created through an expert elicitation process and consist of the Jackson Elk Herd Unit, Grand Teton National Park, …

Increased Positive Tree Species Mixture Effects On The Abundance And Richness Of Collembola With Stand Development In Canadian Boreal Forests, Yakun Zhang, Sai Peng, Zilong Ma, Chen Chen, Bilei Gao, Xinli Chen, Han Y.H. Chen

Aspen Bibliography

It is well established that species mixtures could enhance ecosystem functioning in diverse ecosystem types, with these benefits increasing over time. However, the impact of tree mixtures on Collembola communities following stand development in natural forests remains unclear, despite the critical roles Collembola plays in litter decomposition and nutrient cycling. We investigated the effects of tree species mixtures on Collembola abundance, diversity, and community structure by sampling pure and mixed jack pine (Pinus banksiana Lamb.) and trembling aspen (Populus tremuloides Michx.) of 15-year-old and 41-year-old stands in natural boreal forest. In total, 6,620 individuals of Collembola were identified …

Feasibility Of Producing Non-Structural Wood Products Using Trembling Aspen Lumber, Mengyuan Zhang

Aspen Bibliography

Trembling aspen (Populus tremuloides) is abundant in Canada but underutilized in non-structural solid wood products.This study was aimed at evaluating the feasibility of using aspen lumber to produce flooring, moulding, and siding. The shrinkage, surface roughness, and wettability of aspen wood were tested. The surface hardness, screw withdrawal resistance, colour change, and dimensional stability of there products fabricated were examined. The wood yield of each product was analyzed. It was found that aspen showed superior machinability and wettability to silver maple and yellow poplar. Aspen flooring had a Brinell hardness of 13.47 MPa, 60% lower than silver maple. …

Potential Of Using Trembling Aspen To Make Structural Engineered Wood Products, Dawei Wang

Aspen Bibliography

Trembling aspen (Populus tremuloides) is abundant in Canada but is widely considered an underutilized species. This study was aimed at evaluating the potential of using aspen lumber to produce cross-laminated timber (CLT), glued-laminated timber (glulam), and wood I-joists. The key mechanical properties of these engineered wood products, which were fabricated using a modified grading criterion, were examined. It was found that 1) The mean effective bending stiffness and characteristic bending moment resistance of 5-layer CLT specimens in the major-strength direction were 5,069x10⁹ N·mm²/m and 97.65x10⁶ N·mm/m; 2) The mean apparent MOE and characteristic modulus …

Habitat Loss And Its Behavioral Effects On A Female Gray Hawk In The Lower Rio Grande Valley Of Texas, Usa, Michael T. Stewart, Ashley M. Tanner, Brian A. Millsap, William S. Clark

Human–Wildlife Interactions

Habitat loss is a major threat to wildlife worldwide. While habitat loss is commonly associated with the fragmentation, degradation, or destruction of large tracts of suitable space, habitat loss in urban environments can be much more incremental and nuanced. We tracked an adult female gray hawk (Buteo plagiatus) in the Lower Rio Grande Valley of Texas, USA, before and after 70% of the trees (7.6 ha) were cleared from the core of the nesting territory. While the hawk’s overall activity budget between within-patch and exploratory movements was unchanged, the hawk undertook substantially longer exploratory movements after the trees …

Human–Wildlife Interactions Monograph Series

Human–Wildlife Interactions

The Human–Wildlife Interactions (HWI) Monograph Series is published in both print and online formats through the Jack H. Berryman Institute at Utah State University. See the current and forthcoming publications in this series.

Urban Coyotes As A Source Of Conflict With Humans: An Evaluation Of Common Management Practices, Paul D. Curtis, David L. Bergman, Angeline Barker, Daniel Bogan, Mary Ann Bonnell, Pierre Canac-Marquis, David Drake, Dave Kay, Brian F. Wakeling, H. Bryant White

Human–Wildlife Interactions Monographs

Wildlife often serves as a catalyst for conflict among stakeholders. Management actions that are intended to address sources of disagreement may initiate additional conflict. The Association of Fish and Wildlife Agencies Human–Wildlife Conflict Working Group initiated an effort to identify management actions commonly used to address unwanted coyote (Canis latrans) interactions within urban environments and identify the benefits and challenges associated with each action. Challenges with coyotes in urban environments include aggressive behavior toward humans and pets, attacks, disease exposure, and domestic livestock damage. Although elimination of all attractants would prove preventative in most instances, in practice this …

Monograph Available: Urban Coyotes As A Source Of Conflict With Humans: An Evaluation Of Common Management Practices

Human–Wildlife Interactions

This is an announcement about the published monograph titled "Urban Coyotes as a Source of Conflict with Humans: An Evaluation of Common Management Practices." This publication, part of the HWI Monograph Series, is online and open access.

Use Of Scat Dna To Estimate Coyote Abundance On A Newly Colonized Barrier Island, Sonia M. Hernandez, Michael J. Yabsley, Sarah C. Webster, Elizabeth M. Kierepka, Rochelle R. Beasley, Carly L. Landa, Heather W. Barron, Kelly Sloan, Holly Milbrandt, James C. Beasley

Human–Wildlife Interactions

Coyotes (Canis latrans) have expanded in mainland eastern North America and are known to have successfully colonized numerous islands. However, there are scarce data on the densities of coyotes in these ecosystems, in which coyotes can have substantive negative impacts. Coyotes first colonized Sanibel Island, a barrier island off the western coast of Florida, USA, in 2011, and their presence has been linked to declines in several sensitive species. However, the population size of coyotes has only been estimated from anecdotal reports and camera traps. Our goal was to estimate the size of the coyote population on Sanibel …

Cost-Effective Strategies For Feral Swine Control: Exploring Trapping Equipment Cooperatives, Phil Kenkel, Riza Radmehr, Rodney Holcomb, Mckenzie Boyce

Human–Wildlife Interactions

Feral swine (Sus scrofa) in the United States have become a growing concern, with a population of ≥6 million and causing annual damages of ≥$1.5 billion USD. Because of their high reproductive capacity, effective control methods are crucial to reducing or slowing their population growth. While remotely monitored and triggered traps have proven to be an effective control strategy, the cost of sophisticated trapping equipment, which can cost ≥$7,000 USD, is often cost prohibitive for many landowners. Despite the pressing need to address the challenge of making effective feral swine control methods more affordable, there are few studies …

Factors Influencing The Discovery And Use Of Carrion By Vertebrate Scavengers From Human-Induced Mass-Mortality Events, Samantha J. Leivers, Michael J. Bodenchuk, Tyler A. Campbell, John M. Tomeček

Human–Wildlife Interactions

Scavengers play critical roles in ecosystem health and stability, and both biotic and abiotic factors can influence scavenger guild dynamics. Carrion is often limited both temporally and spatially on the landscape, but mass mortality events (MMEs)—in which there is an influx of carrion biomass on the landscape—may result in different scavenger community dynamics compared to when carrion is scarcely distributed. In this study, we investigated factors affecting the discovery and use of carrion by a natural, unharrassed scavenger guild during wild pig (Sus scrofa) MMEs conducted at East Foundation’s San Antonio Viejo Ranch in South Texas, USA. We …

Using Advanced Machine Learning To Evaluate The Spatial And Temporal Patterns Of Human–Bear Interactions In Maryland, Usa, Katherine A. Kurth, Jonathan K. Trudeau

Human–Wildlife Interactions

American black bears (Ursus americanus) are highly adaptable to human-dominated areas, which can lead to interactions with humans. Managing these interactions is a priority for many wildlife agencies in North America. Climate-induced shortages in natural food can exacerbate human–bear interactions, as bears are driven to seek alternative food sources in human-dominated areas. However, few studies have investigated the impact of climate or weather on the frequency and severity of human–bear interactions. In Maryland, USA, no research has examined the anthropogenic or environmental factors contributing to human–bear interactions, even though reported interactions have consistently increased since the 1990s. Our …

Function Over Form: The Benefits Of Aspen As Surrogate Brood-Rearing Habitat For Greater Sage-Grouse, Michel T. Kohl, Charles P. Sandford, Paul C. Rogers, Renee Chi, Terry A. Messmer, David K. Dahlgren

Aspen Bibliography

Species of conservation concern are often habitat specialists, posing significant risk to those species when specific plant communities are threatened. As a result, practitioners habitually focus conservation efforts on these communities while ignoring ecological mechanisms that explain the wildlife–plant relationships. In doing so, practitioners may overlook alternative vegetation communities that could maintain wildlife populations under alternative conditions (e.g., climate change). Here, we term these areas surrogate habitat, defined as vegetation communities or resource sites that provide similar critical resources as conventional sites, and assess their potential for conservation using a case study of greater sage-grouse (Centrocercus urophasianus) on …

Tree Rings Reveal Mixtures Of Aspen And Spruce Exhibit Greater Drought Resilience In A Planted Field Experiment, Jéssica Chaves Cardoso, Linhao Wu, Marcel Schneider, Charles A. Nock

Aspen Bibliography

Boreal forests provide a wealth of ecosystem services, many of which are linked to forest productivity. Climate change is expected to increase the frequency, duration, and severity of drought, and undermine the productivity of western boreal forests. Favouring species mixtures has emerged as a potential strategy to increase forest resilience to drought. To test the hypothesis that mixtures of trembling aspen and white spruce were more productive than pure stands because they were more resistant and resilient to drought, we analyzed community and species responses to drought utilizing measurements of annual growth obtained from stem disc samples from a planted …

Assessing Spatial Distribution And Quantification Of Native Trees In Saskatchewan's Prairie Landscape Using Remote Sensing Techniques, Elham Shafeian, Bryan J. Mood, Kenneth W. Belcher, Colin P. Laroque

Aspen Bibliography

The importance of trees in non-forest landscapes has been the focus of only a few studies. However, these trees provide many important ecosystem services. In this study, we mapped and quantified these trees using Sentinel-2 (S2) and very high-resolution (VHR) Google satellite imagery without any field campaigns. We performed a Random Forest (RF) classification to map the spatial distribution of native trees in different scenarios. The optimal model showed an overall accuracy and kappa of 0.99 and 0.98, respectively. We mapped 40,500 km² of tree cover, including native tree cover (approximately 29,565 km²≈10.5%), excluding plantations, regional and …

Condition And Management Futures In A Quaking Aspen Recreation Area. Final Report To Snyderville Basin Special Recreation District, Paul C. Rogers, Georgie Corkery, Anna B. Miller

Aspen Bibliography

In partnership with Snyderville Basin Special Recreation District (SBSRD), we undertook a study of ecological conditions and user preferences within a quaking aspen recreational destination forest. The location, in two sections know as Run-A-Muk and Right Turn Sage (RAM/RTS), has experienced some forest die-off in the principally aspen dominated forest dissected by ski, bike, and hiking trails. Graduate student Georgie Corkery led the study and successfully completed a Master's degree, in addition to providing needed information to SBSRD regarding the status, uses, and preferred actions at this facility. Key outcomes regarding aspen conditions include assigning causal factors—ungulate browsing and elevated …

Ecological Interactions Of Cougars, Deer, And Wild Pigs In The Central Coast Range, California, Mitchell A. Parsons

All Graduate Theses and Dissertations, Fall 2023 to Present

Wild pigs are an introduced species in the Americas that negatively affect ecosystems in many ways. Previous research has documented their negative effects on water quality and vegetation and their potential to spread disease among wildlife, domestic animals, and humans. However, how wild pigs affect predator-prey interactions between native wildlife has received little attention. This research explores multiple interactions between wild pigs, a native predator (cougars), and a native prey (black-tailed deer). First, I studies cougar diet to understand how frequently pigs are used as prey. During this project, I also placed wildlife cameras at cougar killed prey to monitor …

Multi-Decadal Aspen Dynamics Show Recruitment Bottleneck Across Complex Mountain Community, Michael T. Stoddard, Kyle C. Rodman, Connor D. Crouch, David W. Huffman, Peter Z. Fulé, Kristen M. Waring, Margaret M. Moore

Aspen Bibliography

Changes in forest structure and shifts in tree species composition have occurred globally due to climate change and altered disturbance regimes. With climate trending toward warmer and drier conditions, these altered forest communities may reorganize in diverse and unpredictable ways. This is especially true in mountain environments where a range of vegetation types and abiotic conditions coexist. In this study, we used long-term permanent plot data from a site spanning broad environmental gradients to assess regeneration and mortality patterns in populations of aspen (Populus tremuloides). The study site, located on the San Francisco Peaks, Arizona, USA, is near …

The Primacy Of Density-Mediated Indirect Effects In A Community Of Wolves, Elk, And Aspen, Elaine M. Brice, Eric J. Larsen, Daniel R. Stahler, Daniel R. Macnulty

Aspen Bibliography

The removal or addition of a predator in an ecosystem can trigger a trophic cascade, whereby the predator indirectly influences plants and/or abiotic processes via direct effects on its herbivore prey. A trophic cascade can operate through a density-mediated indirect effect (DMIE), where the predator reduces herbivore density via predation, and/or through a trait-mediated indirect effect (TMIE), where the predator induces an herbivore trait response that modifies the herbivore's effect on plants. Manipulative experiments suggest that TMIEs are an equivalent or more important driver of trophic cascades than are DMIEs. Whether this applies generally in nature is uncertain because few …

Nursery Cultural Practices Influence Morphological And Physiological Aspen Seedling Traits: Implications For Post-Fire Restoration, Aalap Dixit, Owen Burney

Aspen Bibliography

Aspen forests are threatened by the impacts of a changing climate and are showing large-scale mortality with meager natural regeneration to restore these loses. Therefore, there is an increasing demand for high-quality aspen seedlings to assist with forest restoration efforts. Nursery cultural practices can be used to alter aspen seedling traits to improve adaptability to dry planting conditions. In this study, the effects of container size (SC10 and D30; 158 and 590 mL, respectively) and nursery irrigation treatment (high and low irrigation; 90% and 70% container capacity, respectively) on seedling growth and a suite of morphological and physiological traits were …

Forest Defoliation By And Invasive Outbreak Insect: Catastrophic Consequences For A Charismatic Mega Moth, Richard L. Lindroth, Mark R. Zierden, Clay J. Morrow, Patricia C. Fernandez

Aspen Bibliography

Earth is now experiencing declines in insect abundance and diversity unparalleled in human history. The drivers underlying those declines are many, complex, and incompletely known. Here, using a natural experiment, we report the first test of the hypothesis that forest defoliation by an invasive outbreak insect compromises the fitness of a native insect via damage-induced increases in toxicity of the forest canopy. We demonstrate that defoliation by the invasive spongy moth (Lymantria dispar) elicits an average 8.4-fold increase in foliar defense expression among aspen (Populus tremuloides) genotypes. In turn, elevated defense dramatically reduces survivorship, feeding, and …

Simulating The Long-Term Response Of Forest Succession To Climate Change In The Boreal Forest Of Northern Ontario, Canada, Guy R. Larocque, F. Wayne Bell, Eric B. Searle, Stephen J. Mayor, Thomas Schiks, Parvin Kalantari

Aspen Bibliography

The effect of climate change on forest dynamics is likely to increase in importance in the forthcoming decades. For this reason, it is essential to predict the extent to which changes in temperature, precipitation, and atmospheric CO₂ might affect the development of forest ecosystems and successional pathways. The gap model ZELIG-CFS was used to simulate the potential long-term effects of climate change on species-specific annual change in mean basal area and stand density under two scenarios of representative concentration pathways (RCP), 4.5 and 8.5, for the boreal forest region of Ontario, Canada, where mean temperature, precipitation, and atmospheric CO …

Modelling Climate Effects On Site Productivity And Developing Site Index Conversion Equations For Jack Pine And Trembling Aspen Mixed Stands, Mahadev Sharma

Aspen Bibliography

Forest site productivity estimates are crucial for making informed forest resource management decisions.These estimates are valuable both for the tree species currently growing in the stands and for those being considered for future stands. Current models are generally designed for pure stands and do not account for the influence of climate on tree growth. Consequently, site index (SI) conversion equations were developed specifically for jack pine (Pinus banksiana Lamb.) and trembling aspen (Populus tremuloides Michx.) trees grown in naturally originated mixed stands. This work involved sampling 186 trees (93 of each species) from 31 even-aged mixed stands (3 …

Socially Valued, Ecologically In Decline: Place Attachment Influences Support For Management Actions In A Quaking Aspen Forest Impacted By Recreation, Soil Contamination, And Ungulates, Georgie Corkery

All Graduate Theses and Dissertations, Fall 2023 to Present

Quaking aspen (Populus tremuloides Michx.) spark strong emotional attachments among many people, yet they are ecologically in decline across North America. Aspen landscapes are also popular outdoor recreation destinations. Site-specific strategies are required for both managing for healthy aspen landscapes and enhancing the outdoor recreation experience. Our study investigated a highly-recreated and ecologically declining aspen forest in Summit County, Utah facing population decline. There were two distinct phases of data collection. First, we evaluated the condition of the aspen and identified potential management actions that could improve the condition of the aspen. Second, we surveyed people who visited the site …

Shifting Paradigms In Recreation Management: Applying Social-Ecological System Frameworks To Parks And Protected Areas, Noah Creany

All Graduate Theses and Dissertations, Fall 2023 to Present

Park and protected area (PPA) recreation management is often characterized by social, ecological, and managerial dimensions. These dimensions have increasingly been conceptualized as social-ecological systems (SESs) to understand the complex interrelationships between them. Contemporary trends of increased visitation on public lands in the United States, including US National Parks, have accentuated the complex interactions between the amount of recreation use, the capacity of the setting, the quality of the visitor experience, and ecological resource conditions. These challenges of managing recreation use and understanding these interactions will be further compounded by climate change and its effects on ecosystem composition and dynamics. …

Advancing Quantitative Approaches For Estimating Avian Population Responses To Environmental Change Using A Data-Rich Species: The American White Pelican, Aimee Michele Van Tatenhove

All Graduate Theses and Dissertations, Fall 2023 to Present

Advancements in wildlife data collection technology and analysis are helping us understand how human-caused environmental change is impacting bird species. Yet data collection for many species remains challenging, and often the data are difficult to analyze. Improved methods for collecting and analyzing avian data are needed to understand how species respond to environmental change. However, before applying new methods to poorly understood species, it is crucial to test methods on well-studied species to ensure their effectiveness. The American White Pelican is a well-studied species that is ideal for testing new analysis methods. Pelicans have been studied extensively due to conservation …

Impacts Of Anthropogenic Disturbances And Urbanization On The Behavior And Morphology Of Two Free-Living Lizard Species (Uta Stansburiana And Aspidoscelis Neotesselatus), Layne O. Sermersheim

All Graduate Theses and Dissertations, Fall 2023 to Present

Urbanization can alter wildlife, requiring species to adjust to anthropogenic changes via life history strategies. Reptiles are particularly vulnerable to these changes, as ectotherms directly rely on their environment to maintain their optimal homeostatic state. As urbanization changes the landscape, reptiles will have to adapt to anthropogenic change, but it is unclear what behaviors may be aiding in this adaptation and whether there are morphological tradeoffs existing to support this change. To analyze the impact of urbanization and anthropogenic disturbances on reptile behavior and morphology, I conducted three research studies on two different species – the common side-blotched lizard and …

The Drivers And Ecological Importance Of Streamflow Permanence For Native Salmonids: Evaluated At Multiple Spatio-Temporal Scales, Skylar Rousseau

All Graduate Theses and Dissertations, Fall 2023 to Present

In freshwater ecosystems, aquatic resources are distributed patchily across both space and time. Non-permanent streams, which go through periodic episodes of drying and rewetting, account for more than half of all streams in North America and help create much of the diversity that defines aquatic ecosystem form and function. While non-permanent streams have become increasingly common under climate change, we have a poor understanding of both their distribution across the landscape as well as how native stream fishes make use of them when they are flowing. I analyzed a large data set that spanned multiple decades across the northern Rocky …