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Full-Text Articles in Life Sciences
Investigating The Dynamics Of Elk Population Size And Body Mass In A Seasonal Environment Using A Mechanistic Integral Projection Model, Shelly Lachish, Ellen E. Brandell, Meggan E. Craft, Andrew P. Dobson, Peter J. Hudson, Daniel R. Macnulty, Tim Coulson
Investigating The Dynamics Of Elk Population Size And Body Mass In A Seasonal Environment Using A Mechanistic Integral Projection Model, Shelly Lachish, Ellen E. Brandell, Meggan E. Craft, Andrew P. Dobson, Peter J. Hudson, Daniel R. Macnulty, Tim Coulson
Wildland Resources Faculty Publications
Environmentally mediated changes in body size often underlie population responses to environmental change, yet this is not a universal phenomenon. Understanding when phenotypic change underlies population responses to environmental change is important for obtaining insights and robust predictions of population dynamics in a changing world. We develop a dynamic integral projection model that mechanistically links environmental conditions to demographic rates and phenotypic traits (body size) via changes in resource availability and individual energetics. We apply the model to the northern Yellowstone elk population and explore population responses to changing patterns of seasonality, incorporating the interdependence of growth, demography, and density-dependent …
Weak Interspecific Interactions In A Sagebrush Steppe? Conflicting Evidence From Observations And Experiments, Peter B. Adler, Andrew R. Kleinhesselink, Giles Hooker, Joshua B. Taylor, Brittany J. Teller, Stephen P. Ellner
Weak Interspecific Interactions In A Sagebrush Steppe? Conflicting Evidence From Observations And Experiments, Peter B. Adler, Andrew R. Kleinhesselink, Giles Hooker, Joshua B. Taylor, Brittany J. Teller, Stephen P. Ellner
Wildland Resources Faculty Publications
Stable coexistence requires intraspecific limitations to be stronger than interspecific limitations. The greater the difference between intra‐ and interspecific limitations, the more stable the coexistence, and the weaker the competitive release any species should experience following removal of competitors. We conducted a removal experiment to test whether a previously estimated model, showing surprisingly weak interspecific competition for four dominant species in a sagebrush steppe, accurately predicts competitive release. Our treatments were (1) removal of all perennial grasses and (2) removal of the dominant shrub, Artemisia tripartita. We regressed survival, growth, and recruitment on the locations, sizes, and species identities …
Genetic Variation Determines Which Feedbacks Drive And Alter Predator–Prey Eco-Evolutionary Cycles, Michael H. Cortez
Genetic Variation Determines Which Feedbacks Drive And Alter Predator–Prey Eco-Evolutionary Cycles, Michael H. Cortez
Mathematics and Statistics Faculty Publications
Evolution can alter the ecological dynamics of communities, but the effects depend on the magnitudes of standing genetic variation in the evolving species. Using an eco‐coevolutionary predator–prey model, I identify how the magnitudes of prey and predator standing genetic variation determine when ecological, evolutionary, and eco‐evolutionary feedbacks influence system stability and the phase lags in predator–prey cycles. Here, feedbacks are defined by subsystems, i.e., the dynamics of a subset of the components of the whole system when the other components are held fixed; ecological (evolutionary) feedbacks involve the direct and indirect effects between population densities (species traits) and eco‐evolutionary feedbacks …
Patterns In Greater Sage-Grouse Population Dynamics Correspond With Public Grazing Records At Broad Scales, Adrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. Casazza
Patterns In Greater Sage-Grouse Population Dynamics Correspond With Public Grazing Records At Broad Scales, Adrian P. Monroe, Cameron L. Aldridge, Timothy J. Assal, Kari E. Veblen, David A. Pyke, Michael L. Casazza
Wildland Resources Faculty Publications
Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land-use effects is often generalized from short-term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming, USA, and we used Greater Sage-grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage-grouse from 743 leks (breeding display sites) during 2004-2014, we modeled population trends in response to grazing level (represented by a relative grazing index) …
Climate Influences The Demography Of Three Dominant Sagebrush Steppe Plants, Harmony Dalgleish, David N. Koons, Melvin Hooten, Corey Moffet, Peter B. Adler
Climate Influences The Demography Of Three Dominant Sagebrush Steppe Plants, Harmony Dalgleish, David N. Koons, Melvin Hooten, Corey Moffet, Peter B. Adler
Wildland Resources Faculty Publications
Climate change could alter the population growth of dominant species, leading to profound effects on community structure and ecosystem dynamics. Understanding the links between historical variation in climate and population vital rates (survival, growth, recruitment) is one way to predict the impact of future climate change. Using a unique, long-term dataset from eastern Idaho, we parameterized Integral Projection Models for Pseudoroegneria spicata, Hesperostipa comata, and Artemisia tripartita to identify the demographic rates and climate variables most important for population growth. We described survival, growth and recruitment as a function of genet size using mixed effect regression models that …
Environmental Variation, Stochastic Extinction, And Competitive Coexistence, Peter B. Adler, John M. Drake
Environmental Variation, Stochastic Extinction, And Competitive Coexistence, Peter B. Adler, John M. Drake
Wildland Resources Faculty Publications
Understanding how environmental fluctuations affect population persistence is essential for predicting the ecological impacts of expected future increases in climate variability. However, two bodies of theory make opposite predictions about the effect of environmental variation on persistence. Single‐species theory, common in conservation biology and population viability analyses, suggests that environmental variation increases the risk of stochastic extinction. By contrast, coexistence theory has shown that environmental variation can buffer inferior competitors against competitive exclusion through a storage effect. We reconcile these two perspectives by showing that in the presence of demographic stochasticity, environmental variation can increase the chance of extinction while …