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Articles 1 - 14 of 14

Full-Text Articles in Physical Sciences and Mathematics

Sampling Bias Overestimates Climate Change Impacts On Forest Growth In The Southwestern United States, Stefan Klesse, R. Justin Derose, Christopher H. Guiterman, Ann M. Lynch, Christopher D. O’Connor, John D. Shaw, Margaret E.K. Evans Dec 2018

Sampling Bias Overestimates Climate Change Impacts On Forest Growth In The Southwestern United States, Stefan Klesse, R. Justin Derose, Christopher H. Guiterman, Ann M. Lynch, Christopher D. O’Connor, John D. Shaw, Margaret E.K. Evans

Wildland Resources Faculty Publications

Climate−tree growth relationships recorded in annual growth rings have recently been the basis for projecting climate change impacts on forests. However, most trees and sample sites represented in the International Tree-Ring Data Bank (ITRDB) were chosen to maximize climate signal and are characterized by marginal growing conditions not representative of the larger forest ecosystem. We evaluate the magnitude of this potential bias using a spatially unbiased tree-ring network collected by the USFS Forest Inventory and Analysis (FIA) program. We show that U.S. Southwest ITRDB samples overestimate regional forest climate sensitivity by 41–59%, because ITRDB trees were sampled at warmer and …


Parental Habituation To Human Disturbance Over Time Reduces Fear Of Humans In Coyote Offspring, Christopher J. Schell, Julie K. Young, Elizabeth V. Lonsdorf, Rachel M. Santymire, Jill M. Mateo Dec 2018

Parental Habituation To Human Disturbance Over Time Reduces Fear Of Humans In Coyote Offspring, Christopher J. Schell, Julie K. Young, Elizabeth V. Lonsdorf, Rachel M. Santymire, Jill M. Mateo

Wildland Resources Faculty Publications

A fundamental tenet of maternal effects assumes that maternal variance over time should have discordant consequences for offspring traits across litters. Yet, seldom are parents observed across multiple reproductive bouts, with few studies consider‐ ing anthropogenic disturbances as an ecological driver of maternal effects. We ob‐ served captive coyote (Canis latrans) pairs over two successive litters to determine whether among‐litter differences in behavior (i.e., risk‐taking) and hormones (i.e., cortisol and testosterone) corresponded with parental plasticity in habituation. Thus, we explicitly test the hypothesis that accumulating experiences of anthropogenic disturbance reduces parental fear across reproductive bouts, which should have disparate phenotypic …


Waterfall Formation At A Desert River-Reservoir Delta Isolates Endangered Fishes, Charles N. Cathcart, Casey A. Pennock, Christopher A. Cheek, Mark C. Mckinstry, Peter D. Mackinnon, Mary M. Conner, Keith B. Gido Sep 2018

Waterfall Formation At A Desert River-Reservoir Delta Isolates Endangered Fishes, Charles N. Cathcart, Casey A. Pennock, Christopher A. Cheek, Mark C. Mckinstry, Peter D. Mackinnon, Mary M. Conner, Keith B. Gido

Wildland Resources Faculty Publications

Unforeseen interactions of dams and declining water availability have formed new obstacles to recovering endemic and endangered big-river fishes. During a recent trend of drying climate and declining reservoir water levels in the southwestern United States, a large waterfall has formed on two separate occasions (1989-1995 & 2001-present) in the transition zone between the San Juan River and Lake Powell reservoir because of deposited sediments. Because recovery plans for two large-bodied endangered fish species, razorback sucker (Xyrauchen texanus) and Colorado pikeminnow (Ptychocheilus lucius), include annual stockings in the San Juan River, this waterfall potentially blocks upstream …


Climatic Drivers Of Ponderosa Pine Growth In Central Idaho, Joseph L. Pettit, R. Justin Derose, James N. Long Jul 2018

Climatic Drivers Of Ponderosa Pine Growth In Central Idaho, Joseph L. Pettit, R. Justin Derose, James N. Long

Wildland Resources Faculty Publications

Despite the widespread use of ponderosa pine as an important hydroclimate proxy, we actually understand very little about its climate response in the Northern Rockies. Here, we analyze two new ponderosa pine chronologies to investigate how climate influences annual growth. Despite differences in precipitation amount and timing and large elevation differences (1820 m versus 1060 m), ring width at both sites was strongly driven by water availability. The mid-elevation, water-limited site responded well to previous fall precipitation whereas the wetter, high-elevation site responded to growing season precipitation and temperature. When precipitation and temperature were simultaneously accounted for using the standardized …


Woodland Caribou Habitat Selection Patterns In Relation To Predation Risk And Forage Abundance Depend On Reproductive State, Rebecca Viejou, Tal Avgar, Glen S. Brown, Brent R. Patterson, Doug E. B. Reid, Arthur R. Rodgers, Jennifer Shuter, Ian D. Thompson, John M. Fryxell May 2018

Woodland Caribou Habitat Selection Patterns In Relation To Predation Risk And Forage Abundance Depend On Reproductive State, Rebecca Viejou, Tal Avgar, Glen S. Brown, Brent R. Patterson, Doug E. B. Reid, Arthur R. Rodgers, Jennifer Shuter, Ian D. Thompson, John M. Fryxell

Wildland Resources Faculty Publications

The ideal free distribution assumes that animals select habitats that are beneficial to their fitness. When the needs of dependent offspring differ from those of the parent, ideal habitat selection patterns could vary with the presence or absence of offspring. We test whether habitat selection depends on reproductive state due to top‐down or bottom‐up influences on the fitness of woodland caribou (Rangifer tarandus caribou), a threatened, wide‐ranging herbivore. We combined established methods of fitting resource and step selection functions derived from locations of collared animals in Ontario with newer techniques, including identifying calf status from video collar footage and seasonal …


Low Offspring Survival In Mountain Pine Beetle Infesting The Resistant Great Basin Bristlecone Pine Supports The Preference-Performance Hypothesis, Erika L. Eidson, Karen E. Mock, Barbara J. Bentz May 2018

Low Offspring Survival In Mountain Pine Beetle Infesting The Resistant Great Basin Bristlecone Pine Supports The Preference-Performance Hypothesis, Erika L. Eidson, Karen E. Mock, Barbara J. Bentz

Wildland Resources Faculty Publications

The preference-performance hypothesis states that ovipositing phytophagous insects will select host plants that are well-suited for their offspring and avoid host plants that do not support offspring performance (survival, development and fitness). The mountain pine beetle (Dendroctonus ponderosae), a native insect herbivore in western North America, can successfully attack and reproduce in most species of Pinus throughout its native range. However, mountain pine beetles avoid attacking Great Basin bristlecone pine (Pinus longaeva), despite recent climate-driven increases in mountain pine beetle populations at the high elevations where Great Basin bristlecone pine grows. Low preference for a potential …


Spatial Processes Decouple Management From Objectives In A Heterogeneous Landscape: Predator Control As A Case Study, Peter J. Mahoney, Julie K. Young, Kent R. Hersey, Randy T. Larsen, Brock R. Mcmillan, David C. Stoner Apr 2018

Spatial Processes Decouple Management From Objectives In A Heterogeneous Landscape: Predator Control As A Case Study, Peter J. Mahoney, Julie K. Young, Kent R. Hersey, Randy T. Larsen, Brock R. Mcmillan, David C. Stoner

Wildland Resources Faculty Publications

Predator control is often implemented with the intent of disrupting top‐down regulation in sensitive prey populations. However, ambiguity surrounding the efficacy of predator management, as well as the strength of top‐down effects of predators in general, is often exacerbated by the spatially implicit analytical approaches used in assessing data with explicit spatial structure. Here, we highlight the importance of considering spatial context in the case of a predator control study in south‐central Utah. We assessed the spatial match between aerial removal risk in coyotes (Canis latrans) and mule deer (Odocoileus hemionus) resource selection during parturition using …


Gymnosperms On The Edge, Félix Forest, Justin Moat, Elisabeth Baloch, Neil A. Brummitt, Steve P. Bachman, Steffi Ickert-Bond, Peter M. Hollingsworth, Aaron Liston, Damon P. Little, Sarah Mathews, Hardeep Rai, Catarina Rydin, Dennis W. Stevenson, Philip Thomas, Sven Buerki Apr 2018

Gymnosperms On The Edge, Félix Forest, Justin Moat, Elisabeth Baloch, Neil A. Brummitt, Steve P. Bachman, Steffi Ickert-Bond, Peter M. Hollingsworth, Aaron Liston, Damon P. Little, Sarah Mathews, Hardeep Rai, Catarina Rydin, Dennis W. Stevenson, Philip Thomas, Sven Buerki

Wildland Resources Faculty Publications

Driven by limited resources and a sense of urgency, the prioritization of species for conservation has been a persistent concern in conservation science. Gymnosperms (comprising ginkgo, conifers, cycads, and gnetophytes) are one of the most threatened groups of living organisms, with 40% of the species at high risk of extinction, about twice as many as the most recent estimates for all plants (i.e. 21.4%). This high proportion of species facing extinction highlights the urgent action required to secure their future through an objective prioritization approach. The Evolutionary Distinct and Globally Endangered (EDGE) method rapidly ranks species based on their evolutionary …


Phenological Mismatch In Coastal Western Alaska May Increase Summer Season Greenhouse Gas Uptake, Katharine C. Kelsey, A. Joshua Leffler, Karen H. Beard, Ryan T. Choi, Joel A. Schmutz, Jeffery M. Welker Apr 2018

Phenological Mismatch In Coastal Western Alaska May Increase Summer Season Greenhouse Gas Uptake, Katharine C. Kelsey, A. Joshua Leffler, Karen H. Beard, Ryan T. Choi, Joel A. Schmutz, Jeffery M. Welker

Wildland Resources Faculty Publications

High latitude ecosystems are prone to phenological mismatches due to climate change- driven advances in the growing season and changing arrival times of migratory herbivores. These changes have the potential to alter biogeochemical cycling and contribute to feedbacks on climate change by altering greenhouse gas (GHG) emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) through large regions of the Arctic. Yet the effects of phenological mismatches on gas fluxes are currently unexplored. We used a three-year field experiment that altered the start of the growing season and timing of grazing to …


Site Conditions Determine A Key Native Plant’S Contribution To Invasion Resistance In Grasslands, Kristin B. Hulvey, Brittany J. Teller Mar 2018

Site Conditions Determine A Key Native Plant’S Contribution To Invasion Resistance In Grasslands, Kristin B. Hulvey, Brittany J. Teller

Wildland Resources Faculty Publications

Many plant invasion studies in grasslands suggest that resident plants that share functional traits with invaders can reduce invasion by competing for limiting resources. However, since invasion studies often occur in highly controlled plots or microcosms, it is unclear how heterogeneous site conditions alter competitive interactions under realistic scenarios. To explore how landscape heterogeneity affects biotic resistance provided by competitive resident plants, we conducted a field‐based experiment across four sites in California grasslands. Plots contained naturally occurring populations of native Hemizonia congesta, but differed in other characteristics, including litter cover, annual grass cover, soil moisture, and species richness. We invaded …


Direct Effects Of Warming Increase Woody Plant Abundance In A Subarctic Wetland, Lindsay G. Carlson, Karen H. Beard, Peter B. Adler Feb 2018

Direct Effects Of Warming Increase Woody Plant Abundance In A Subarctic Wetland, Lindsay G. Carlson, Karen H. Beard, Peter B. Adler

Wildland Resources Faculty Publications

Both the direct effects of warming on a species’ vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long-term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii, and a dwarf …


Animal Movement Affectsinterpretation Of Occupancy Models From Camera Trap Surveys Of Unmarked Animals, Eric W. Neilson, Tal Avgar, A. Cole Burton, Kate Broadley, Stan Boutin Jan 2018

Animal Movement Affectsinterpretation Of Occupancy Models From Camera Trap Surveys Of Unmarked Animals, Eric W. Neilson, Tal Avgar, A. Cole Burton, Kate Broadley, Stan Boutin

Wildland Resources Faculty Publications

Occupancy models are increasingly applied to data from wildlife camera-trap (CT) surveys to estimate distribution, habitat use, or relative abundance of unmarked animals. Fundamental to the occupancy modeling framework is the temporal pattern of detections at camera stations, which is influenced by animal population density and the speed and scale of animal movement. How these factors interact with CT sampling designs to affect the interpretation of occupancy parameter estimates is unclear. We developed a simple yet ecologically relevant animal movement simulation to create CT detections for animal populations varying in movement rate, home range area, and population density. We also …


Survival Rates Indicate That Correlations Between Community-Weighted Mean Traits And Environments Can Be Unreliable Estimates Of The Adaptive Value Of Traits, Daniel C. Laughlin, Robert T. Strahan, Peter B. Adler, Margaret M. Moore Jan 2018

Survival Rates Indicate That Correlations Between Community-Weighted Mean Traits And Environments Can Be Unreliable Estimates Of The Adaptive Value Of Traits, Daniel C. Laughlin, Robert T. Strahan, Peter B. Adler, Margaret M. Moore

Wildland Resources Faculty Publications

Correlations between community-weighted mean (CWM) traits and environmental gradients are often assumed to quantify the adaptive value of traits. We tested this assumption by comparing these correlations with models of survival probability using 46 perennial species from long-term permanent plots in pine forests of Arizona. Survival was modeled as a function of trait-by-environment interactions, plant size, climatic variation, and neighborhood competition. The effect of traits on survival depended on the environmental conditions, but the two statistical approaches were inconsistent. For example, CWM specific leaf area (SLA) and soil fertility were uncorrelated. However, survival was highest for species with low SLA …


Community-Level Plant–Soil Feedbacks Explain Landscape Distribution Of Native And Non-Native Plants, Andrew Kulmatiski Jan 2018

Community-Level Plant–Soil Feedbacks Explain Landscape Distribution Of Native And Non-Native Plants, Andrew Kulmatiski

Wildland Resources Faculty Publications

Plant–soil feedbacks (PSFs) have gained attention for their potential role in explaining plant growth and invasion. While promising, most PSF research has measured plant monoculture growth on different soils in short-term, greenhouse experiments. Here, five soil types were conditioned by growing one native species, three non-native species, or a mixed plant community in different plots in a common-garden experiment. After 4 years, plants were removed and one native and one non-native plant community were planted into replicate plots of each soil type. After three additional years, the percentage cover of each of the three target species in each community was …