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Full-Text Articles in Physical Sciences and Mathematics

Long-Term Landscape Changes In A Subalpine Spruce-Fir Forest In Central Utah, Usa, Jesse L. Morris, R. Justin Derose, Andrea R. Brunelle Dec 2015

Long-Term Landscape Changes In A Subalpine Spruce-Fir Forest In Central Utah, Usa, Jesse L. Morris, R. Justin Derose, Andrea R. Brunelle

Wildland Resources Faculty Publications

Background: In Western North America, increasing wildfire and outbreaks of native bark beetles have been mediated by warming climate conditions. Bioclimatic models forecast the loss of key high elevation species throughout the region. This study uses retrospective vegetation and fire history data to reconstruct the drivers of past disturbance and environmental change. Understanding the relationship among climate, antecedent disturbances, and the legacy effects of settlement-era logging can help identify the patterns and processes that create landscapes susceptible to bark beetle epidemics. Methods: Our analysis uses data from lake sediment cores, stand inventories, and historical records. Sediment cores were dated with …


Selection For Forage And Avoidance Of Risk By Woodland Caribou (Rangifer Tarandus Caribou) At Coarse Andlocal Scales, Madeleine T. Mcgreer, Erin E. Mallon, Lucas M. Vander Vennen, Philip A. Wiebe, James A. Baker, Glen S. Brown, Tal Avgar, Jevon Hagens, Andrew M. Kittle, Anna Mosser, Garrett M. Street, Doug E. B. Reid, Arthur R. Rodgers, Jennifer Shuter, Ian D. Thompson, Et Al. Dec 2015

Selection For Forage And Avoidance Of Risk By Woodland Caribou (Rangifer Tarandus Caribou) At Coarse Andlocal Scales, Madeleine T. Mcgreer, Erin E. Mallon, Lucas M. Vander Vennen, Philip A. Wiebe, James A. Baker, Glen S. Brown, Tal Avgar, Jevon Hagens, Andrew M. Kittle, Anna Mosser, Garrett M. Street, Doug E. B. Reid, Arthur R. Rodgers, Jennifer Shuter, Ian D. Thompson, Et Al.

Wildland Resources Faculty Publications

The relationship between selection at coarse and fine spatiotemporal spatial scales is still poorly understood. Some authors claim that, to accommodate different needs at different scales, individuals should have contrasting selection patterns at different scales of selection, while others claim that coarse scale selection patterns should reflect fine scale selection decisions. Here we examine site selection by 110 woodland caribou equipped with GPS radio‐collars with respect to forage availability and predation risk across a broad gradient in availability of both variables in boreal forests of Northern Ontario. We tested whether caribou selection for forage and avoidance of risk was consistent …


Genetic Analysis Of The Henry Mountains Bison Herd, Dustin H. Ranglack, Lauren K. Dobson, Johan T. Du Toit, James Derr Dec 2015

Genetic Analysis Of The Henry Mountains Bison Herd, Dustin H. Ranglack, Lauren K. Dobson, Johan T. Du Toit, James Derr

Wildland Resources Faculty Publications

Wild American plains bison (Bison bison) populations virtually disappeared in the late 1800s, with some remnant animals retained in what would become Yellowstone National Park and on private ranches. Some of these private bison were intentionally crossbred with cattle for commercial purposes. This forced hybridization resulted in both mitochondrial and nuclear introgression of cattle genes into some of the extant bison genome. As the private populations grew, excess animals, along with their history of cattle genetics, provided founders for newly established public bison populations. Of the US public bison herds, only those in Yellowstone and Wind Cave National Parks (YNP …


Integrated Step Selection Analysis: Bridgingthe Gap Between Resource Selection And Animal Movement, Tal Avgar, Jonathan R. Potts, Mark A. Lewis, Mark S. Boyce Dec 2015

Integrated Step Selection Analysis: Bridgingthe Gap Between Resource Selection And Animal Movement, Tal Avgar, Jonathan R. Potts, Mark A. Lewis, Mark S. Boyce

Wildland Resources Faculty Publications

A resource selection function is a model of the likelihood that an available spatial unit will be used by an animal, given its resource value. But how do we appropriately define availability? Step selection analysis deals with this problem at the scale of the observed positional data, by matching each ‘used step’ (connecting two consecutive observed positions of the animal) with a set of ‘available steps’ randomly sampled from a distribution of observed steps or their characteristics. Here we present a simple extension to this approach, termed integrated step selection analysis (iSSA), which relaxes the implicit assumption that observed movement …


The First Bromeligenous Species Of Dendropsophus (Anura: Hylidae) From Brazil's Atlantic Forest, Rodrigo Barbosa Ferreira, Julián Faivovich, Karen H. Beard, José P. Pombal Jr Dec 2015

The First Bromeligenous Species Of Dendropsophus (Anura: Hylidae) From Brazil's Atlantic Forest, Rodrigo Barbosa Ferreira, Julián Faivovich, Karen H. Beard, José P. Pombal Jr

Wildland Resources Faculty Publications

We describe a new treefrog species of Dendropsophus collected on rocky outcrops in the Brazilian Atlantic Forest. Ecologically, the new species can be distinguished from all known congeners by having a larval phase associated with rainwater accumulated in bromeliad phytotelms instead of temporary or lentic water bodies. Phylogenetic analysis based on molecular data confirms that the new species is a member of Dendropsophus; our analysis does not assign it to any recognized species group in the genus. Morphologically, based on comparison with the 96 known congeners, the new species is diagnosed by its small size, framed dorsal color pattern, and …


Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski Dec 2015

Modelling Water Uptake Provides A New Perspective On Grass And Tree Coexistence, Michael G. Mazzacavallo, Andrew Kulmatiski

Wildland Resources Faculty Publications

Root biomass distributions have long been used to infer patterns of resource uptake. These patterns are used to understand plant growth, plant coexistence and water budgets. Root biomass, however, may be a poor indicator of resource uptake because large roots typically do not absorb water, fine roots do not absorb water from dry soils and roots of different species can be difficult to differentiate. In a sub-tropical savanna, Kruger Park, South Africa, we used a hydrologic tracer experiment to describe the abundance of active grass and tree roots across the soil profile. We then used this tracer data to parameterize …


Using Life History Trade-Offs To Understand Core-Transient Structuring Of A Small Mammal Community, Sarah R. Supp, David N. Koons, S.K. Morgan Ernest Oct 2015

Using Life History Trade-Offs To Understand Core-Transient Structuring Of A Small Mammal Community, Sarah R. Supp, David N. Koons, S.K. Morgan Ernest

Wildland Resources Faculty Publications

An emerging conceptual framework suggests that communities are composed of two main groups of species through time: core species that are temporally persistent, and transient species that are temporally intermittent. Core and transient species have been shown to differ in spatiotemporal turnover, diversity patterns, and importantly, survival strategies targeted at local versus regional habitat use. While the core-transient framework has typically been a site-specific designation for species, we suggest that if core and transient species have local versus regional survival strategies across sites, and consistently differ in population-level spatial structure and gene flow, they may also typically exhibit different life-history …


Mountain Pine Beetles Use Volatile Cues To Locate Host Limber Pine And Avoid Non-Host Great Basin Bristlecone Pine, Curtis A. Gray, Justin B. Runyon, Michael J. Jenkins, Andrew D. Giunta Sep 2015

Mountain Pine Beetles Use Volatile Cues To Locate Host Limber Pine And Avoid Non-Host Great Basin Bristlecone Pine, Curtis A. Gray, Justin B. Runyon, Michael J. Jenkins, Andrew D. Giunta

Wildland Resources Faculty Publications

The tree-killing mountain pine beetle (Dendroctonus ponderosae Hopkins) is an important disturbance agent of western North American forests and recent outbreaks have affected tens of millions of hectares of trees. Most western North American pines (Pinus spp.) are hosts and are successfully attacked by mountain pine beetles whereas a handful of pine species are not suitable hosts and are rarely attacked. How pioneering females locate host trees is not well understood, with prevailing theory involving random landings and/or visual cues. Here we show that female mountain pine beetles orient toward volatile organic compounds (VOCs) from host limber pine (Pinus flexilis …


Characterizing Demographicparameters Across Environmental Gradients: A Case Study With Ontario Moose, Garrett M. Street, Tal Avgar, Arthur R. Rodgers, John M. Fryxell Aug 2015

Characterizing Demographicparameters Across Environmental Gradients: A Case Study With Ontario Moose, Garrett M. Street, Tal Avgar, Arthur R. Rodgers, John M. Fryxell

Wildland Resources Faculty Publications

Population-level demographic characteristics as estimated by standard logistic growth models (i.e., carrying capacity and intrinsic growth rate) should vary with changes in habitat quality and availability of resources. However, few published studies have tested this hypothesis by comparing population growth rates across broad bioclimatic gradients, and fewer still the carrying capacities of those populations. We used time series data on moose (Alces alces) population densities based on aerial census and hunter harvest data for 34 management units across Ontario to estimate local carrying capacities and intrinsic growth rates. These population parameters were then regressed against associated habitat covariates for each …


Wolf Diet In An Agricultural Landscape Of North-Eastern Turkey, Claudia Capitani, Mark William Chynoweth, Josip Kusak, Emrah Çoban, Çağan H. Şekercioğlu Jun 2015

Wolf Diet In An Agricultural Landscape Of North-Eastern Turkey, Claudia Capitani, Mark William Chynoweth, Josip Kusak, Emrah Çoban, Çağan H. Şekercioğlu

Wildland Resources Faculty Publications

In this study, we investigated wolf feeding ecology in Kars province, north-eastern Turkey, by analysing 72 scat samples collected in spring 2013. Ongoing camera trap surveys suggest that large wild ungulates are exceptionally rare in the region. On the contrary, livestock is abundant. Accordingly, scats analysis revealed that livestock constituted most of the biomass intake for wolves, although small mammals were the most frequent prey items. Wild ungulates were occasional prey, and although wolves make use of the main village garbage dump as a food source, garbage remains were scarce in scat samples. Wolf dependence on anthropogenic resources, primarily livestock, …


Recolonizing Wolves And Mesopredator Suppression Of Coyotes:Impacts On Pronghorn Population Dynamics, Kim Murray Berger, Mary M. Conner May 2015

Recolonizing Wolves And Mesopredator Suppression Of Coyotes:Impacts On Pronghorn Population Dynamics, Kim Murray Berger, Mary M. Conner

Wildland Resources Faculty Publications

Food web theory predicts that the loss of large carnivores may contribute toelevated predation rates and, hence, declining prey populations, through the process ofmesopredator release. However, opportunities to test predictions of the mesopredator releasehypothesis are rare, and the extent to which changes in predation rates influence preypopulation dynamics may not be clear due to a lack of demographic information on the preypopulation of interest. We utilized spatial and seasonal heterogeneity in wolf distribution andabundance to evaluate whether mesopredator release of coyotes (Canis latrans), resulting fromthe extirpation of wolves (Canis lupus) throughout much of the United States, contributes tohigh rates of …


Home Range Use And Movement Patterns Of Non-Native Feral Goats In A Tropical Island Montane Dry Landscape, Mark William Chynoweth, Christopher A. Lepczyk, Creighton M. Litton, Steven C. Hess, James R. Kellner, Susan Cordell Mar 2015

Home Range Use And Movement Patterns Of Non-Native Feral Goats In A Tropical Island Montane Dry Landscape, Mark William Chynoweth, Christopher A. Lepczyk, Creighton M. Litton, Steven C. Hess, James R. Kellner, Susan Cordell

Wildland Resources Faculty Publications

Advances in wildlife telemetry and remote sensing technology facilitate studies of broad-scale movements of ungulates in relation to phenological shifts in vegetation. In tropical island dry landscapes, home range use and movements of non-native feral goats (Capra hircus) are largely unknown, yet this information is important to help guide the conservation and restoration of some of the world’s most critically endangered ecosystems. We hypothesized that feral goats would respond to resource pulses in vegetation by traveling to areas of recent green-up. To address this hypothesis, we fitted six male and seven female feral goats with Global Positioning System (GPS) collars …