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Population dynamics

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Assessing Radio Transmitter Weight Effect And Evaluation Of Northern Bobwhite Chick Survival In Coastal North Carolina, Autumn S. Randall, Theron M. Terhune Ii, Matthew T. Springer, Darin J. Mcneil Jan 2026

Assessing Radio Transmitter Weight Effect And Evaluation Of Northern Bobwhite Chick Survival In Coastal North Carolina, Autumn S. Randall, Theron M. Terhune Ii, Matthew T. Springer, Darin J. Mcneil

Forestry and Natural Resources Faculty Publications

Studies on the earliest life stages are essential to our ecological understanding of avian demography; however, monitoring technologies that allow tracking of small birds are still limited in a variety of ways. One critical limitation, until recently, has been the development of methods for attaching transmitters to young birds with precocial development (e.g., Galliformes, Charadriiformes, etc.). The modified suture technique offers a means to attach transmitters to precocial chicks while accommodating rapid growth characterized by birds with precocial young. Although the sutured transmitter method was developed for northern bobwhite (Colinus virginianus) chicks, there remain key unknowns regarding best …


Demography And Habitat Associations Of The Basalt Cactus Pediocactus Nigrispinus, Zarha S. Dillon-Zuppelli, Mary E. Poulson, Eric A. Graham Apr 2025

Demography And Habitat Associations Of The Basalt Cactus Pediocactus Nigrispinus, Zarha S. Dillon-Zuppelli, Mary E. Poulson, Eric A. Graham

Biology Faculty Scholarship

Cacti are iconic members of arid ecosystems. Pediocactus nigrispinus is a species of cactus endemic to the Pacific Northwest and has been listed as a sensitive species due to its vulnerability to habitat loss. Best conservation methods for this species are poorly understood, due in part to a limited understanding of its demography and habitat associations that may help define its occurrence. A demographic study from four plots in Washington State was implemented in 2016 to provide a baseline of the population dynamics for P. nigrispinus and to enhance conservation efforts for this sensitive species. Five years of size, fecundity, …


The Age, Period, And Cohort Effects On Crime Rates In The Republic Of Korea, Byunggu Kang Jan 2023

The Age, Period, And Cohort Effects On Crime Rates In The Republic Of Korea, Byunggu Kang

Legacy Theses & Dissertations (2009 - 2024)

The age–crime relationship has been a theoretical and empirical puzzle for criminologists for decades. Although the age–crime curve is often considered a stylized fact, a large body of research suggests that the age–crime relationship is dynamic under the influence of age, period, and cohort effects. The impact of these effects can vary across different social contexts, as the consistency or variability in socio-economic and cultural factors experienced by consecutive generations or populations differs in each context. Thus, the extent to which age, period, and cohort effects contribute to the age–crime relationship in various social contexts is a question that requires …


Predicting Effects Of Climate Change On Productivity And Persistence Of Forest Trees, Russell D. Kramer, H. Roaki Ishii, Kelsey R. Carter, Yuko Miyazaki, Molly A. Cavaleri, Masatake G. Araki, Wakana A. Azuma, Yuta Inoue, Chinatsu Hara Jul 2020

Predicting Effects Of Climate Change On Productivity And Persistence Of Forest Trees, Russell D. Kramer, H. Roaki Ishii, Kelsey R. Carter, Yuko Miyazaki, Molly A. Cavaleri, Masatake G. Araki, Wakana A. Azuma, Yuta Inoue, Chinatsu Hara

Michigan Tech Publications, Part 1

Global climate change increases uncertainty in sustained functioning of forest ecosystems. Forest canopies are a key link between terrestrial ecosystems, the atmosphere, and climate. Here, we introduce research presented at the 66th meeting of the Ecological Society of Japan in the symposium “Structure and function of forest canopies under climate change.” Old-growth forest carbon stores are the largest and may be the most vulnerable to climate change as the balance between sequestration and emission could easily be tipped. Detailed structural analysis of individual large, old trees shows they are allocating wood to the trunk and crown in patterns that cannot …


Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone Apr 2017

Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone

Virginia Journal of Science

We used monthly live trapping for 2.5 years to evaluate the life-history features of the most common small mammal, Sigmodon hispidus (hispid cotton rat), in an old field at its northern limit of distribution on the Atlantic Coast. Peak densities, achieved in late autumn or early winter, were among the highest recorded for the species and were more typical of geographically marginal populations rather than of central ones. Unlike some other marginal populations, hispid cotton rats in southeastern Virginia did not lose significant body mass over the winter (when few juveniles were present) and survival in winter was not significantly …


Differential Impacts Of Wildfire On The Population Dynamics Of An Old-Forest Species, Jeremy T. Rockweit, Alan B. Franklin, Peter C. Carlson Jan 2017

Differential Impacts Of Wildfire On The Population Dynamics Of An Old-Forest Species, Jeremy T. Rockweit, Alan B. Franklin, Peter C. Carlson

United States Department of Agriculture Wildlife Services: Staff Publications

Ecological disturbances shape and maintain natural communities, but climate change and human land use can alter disturbance regimes and affect population persistence and vital rates in unpredictable ways. Species inhabiting landscapes shaped by wildfire have evolved mechanisms allowing them to persist under this dynamic disturbance type, which creates habitats of varying quality for these species. We utilized data from a 26-yr demographic study of northern spotted owls to analyze the influence of wildfire on apparent survival and recruitment rates. Wildfires occurred across different years and affected different spotted owl territories, which allowed us to implement a retrospective Before-After-Control-Impact (BACI) analysis …


The Demography And Determinants Of Population Growth In Utah Moose (Alces Alces Shirasi), Joel S. Ruprecht May 2016

The Demography And Determinants Of Population Growth In Utah Moose (Alces Alces Shirasi), Joel S. Ruprecht

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Moose (Alces alces) occur widely in northern regions of the world. Across their distribution, the species is considered to be of high intrinsic, ecological and recreational value. Populations of moose along their southern range limit in North America have shown erratic population dynamics in recent decades including severe numeric declines in some areas. Moose in Utah belong to the Shiras subspecies, which is a relatively understudied population segment. Additionally, moose in Utah represent the southernmost naturally occurring moose populations worldwide. Concerns over possible declines and a paucity of baseline data on moose within the state prompted the Utah …


Quantifying Demographic Uncertainty: Bayesian Methods For Integral Projection Models, Bret D. Elderd, Tom E.X. Miller Feb 2016

Quantifying Demographic Uncertainty: Bayesian Methods For Integral Projection Models, Bret D. Elderd, Tom E.X. Miller

Faculty Publications

© 2016 by the Ecological Society of America. Integral projection models ( IPM s) are a powerful and popular approach to modeling population dynamics. Generalized linear models form the statistical backbone of an IPM . These models are typically fi t using a frequentist approach. We suggest that hierarchical Bayesian statistical approaches offer important advantages over frequentist methods for building and interpreting IPM s, especially given the hierarchical nature of most demographic studies. Using a stochastic IPM for a desert cactus based on a 10- year study as a worked example, we highlight the application of a Bayesian approach for …


Early Successional Microhabitats Allow The Persistence Of Endangered Plants In Coastal Sand Dunes, Eleanor A. Pardini, Kyle E. Vickstrom, Tiffany M. Knight Apr 2015

Early Successional Microhabitats Allow The Persistence Of Endangered Plants In Coastal Sand Dunes, Eleanor A. Pardini, Kyle E. Vickstrom, Tiffany M. Knight

Biology Faculty Research

Many species are adapted to disturbance and occur within dynamic, mosaic landscapes that contain early and late successional microhabitats. Human modification of disturbance regimes alters the availability of microhabitats and may affect the viability of species in these ecosystems. Because restoring historical disturbance regimes is typically expensive and requires action at large spatial scales, such restoration projects must be justified by linking the persistence of species with successional microhabitats. Coastal sand dune ecosystems worldwide are characterized by their endemic biodiversity and frequent disturbance. Dune-stabilizing invasive plants alter successional dynamics and may threaten species in these ecosystems. We examined the distribution …


A Newly Discovered Large And Significant Population Of Castela Emoryi (Emory’S Crucifixion Thorn, Simaroubaceae) In California, Duncan S. Bell, Tasya Herskovits Jan 2013

A Newly Discovered Large And Significant Population Of Castela Emoryi (Emory’S Crucifixion Thorn, Simaroubaceae) In California, Duncan S. Bell, Tasya Herskovits

Aliso: A Journal of Systematic and Floristic Botany

Castela emoryi is an understudied species, and recent visits to populations across California have shed new light on its distribution and biology, including recruitment, natural history, and herbivory. Field exploration in Rice Valley in Riverside County revealed what is considered to be the largest population of C. emoryi in California. Possible threats and conservation needs of this species are discussed.


The Ecology Of Congeneric Resprouters And Reseeders (Hypericum Spp.) Along Fire-Frequented Pine Savanna Ecoclines, Raelene Marie Crandall Jan 2011

The Ecology Of Congeneric Resprouters And Reseeders (Hypericum Spp.) Along Fire-Frequented Pine Savanna Ecoclines, Raelene Marie Crandall

LSU Doctoral Dissertations

Resprouting and reseeding shrubs are predicted to be restricted to habitats with long and short return intervals of natural disturbances, respectively. Nonetheless, resprouters and reseeders co-occur along Gulf of Mexico coastal ecoclines where lightning-ignited fires were historically frequent. In this collection of studies, I examine fire responses, habitat associations, distribution limits, and seedling recruitment of Hypericum species along ecoclines in pine savannas of the St. Joe Bay State Buffer Preserve in Gulf County of Florida. In this area, ecoclines are characterized by topographic, soil moisture, and fire heterogeneity gradients. Hypericum microsepalum, an obligate resprouter, primarily resprouts following disturbances that …


Contributions Of Demography And Dispersal Parameters To The Spatial Spread Of A Stage-Structured Insect Invasion, Tom E. X. Miller, Brigitte Tenhumberg Jan 2010

Contributions Of Demography And Dispersal Parameters To The Spatial Spread Of A Stage-Structured Insect Invasion, Tom E. X. Miller, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of ‘‘local’’ perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for …


Are Black Bears Declining In Montana? Inference From Multiple Data Sources In The Face Of Uncertainty, Julie Ann Beston Jan 2010

Are Black Bears Declining In Montana? Inference From Multiple Data Sources In The Face Of Uncertainty, Julie Ann Beston

Graduate Student Theses, Dissertations, & Professional Papers

Carnivores are managed both to maintain populations and reduce conflict with humans, but data-based decision-making is difficult due to the expense of data collection. When new fieldwork is impossible, we can benefit from available data in assessing populations. I used demographic and harvest data to assess the population status of black bears (Ursus americanus) in Montana.

I conducted a hierarchical Bayesian meta-analysis of black bear demographic studies to evaluate geographic structuring and estimate vital rates and population growth rate. Adult survival is higher in the west than the east, but the reverse is true for fecundity. The mean …


Population Characteristics Of Interior Double-Crested Cormorants Breeding Across The Southern Border Of Ontario, Jennifer Erin Chastant Dec 2008

Population Characteristics Of Interior Double-Crested Cormorants Breeding Across The Southern Border Of Ontario, Jennifer Erin Chastant

Theses and Dissertations

Interior Double-crested cormorant reproduction was examined on a large geographical scale to evaluate management actions. Three distinct breeding areas across Ontario were selected. Beginning in 2002, over 11,000 preledged cormorants have been marked. During 2006 and 2007, re-observation of banded birds, colony data such as nest, egg, and chick measurements, and island morphology, were collected. Data revealed no significant regional differences in adult size. However, eggs in eastern Lake Ontario (ELO) were larger than North Channel of Lake Huron (NChan) and Lake of the Woods (LOW). Chicks in ELO throughout development were smaller than NChan and LOW. Number of gulls …


Impacts Of Exotic Invasive Vines On The Ecology And Reproduction Of The Endangered Trillium Reliquum, Christopher D. Heckel Dec 2004

Impacts Of Exotic Invasive Vines On The Ecology And Reproduction Of The Endangered Trillium Reliquum, Christopher D. Heckel

College of Graduate Studies: Theses & Dissertations

Trillium reliquum Freeman is an endangered plant restricted to 20 counties in three states that is imperilled by habitat loss and encroachment from the exotic invasive vines, kudzu (Pueraria montana Ohwi) and Japanese honeysuckle (Lonicera japonica Thunb.) My study examines the impact of kudzu and honeysuckle on native plant communities, T. reliquum population dynamics and T. reliquum reproduction.


Conserving Slow-Growing, Long-Lived Tree Species: Input From The Demography Of A Rare Understory Conifer, Taxus Floridana, Charles Kwit, Carol C. Horvitz, William J. Platt Apr 2004

Conserving Slow-Growing, Long-Lived Tree Species: Input From The Demography Of A Rare Understory Conifer, Taxus Floridana, Charles Kwit, Carol C. Horvitz, William J. Platt

Faculty Publications

Although land preservation and promotion of successful regeneration are important conservation actions, their ability to increase population growth rates of slow-growing, long-lived trees is limited. We investigated the demography of Taxus floridana Nutt., a rare understory conifer, in three populations in different ravine forests spanning its entire geographic range along the Apalachicola River Bluffs in northern Florida (U.S.A.). We examined spatial and temporal patterns in demographic parameters and projected population growth rates by using four years of data on the recruitment and survival of seedlings and established stems, and on diameter growth from cross-sections of dead stems. All populations experienced …


Red-Cockaded Woodpecker Recovery: An Integrated Strategy, D. Craig Rudolph, Richard N. Conner, Jeffrey R. Walters Jan 2004

Red-Cockaded Woodpecker Recovery: An Integrated Strategy, D. Craig Rudolph, Richard N. Conner, Jeffrey R. Walters

Faculty Publications

Populations of the red-cockaded woodpecker (Picoides borealis) have experienced massive declines since European colonization of North America. This is due to extensive habitat loss and alteration. Logging of old-growth pine forests and alteration of the fire regime throughout the historic range of the species were the primary causes of population decline. Listing of the red-cockaded woodpecker under the Endangered Species Act of 1973, as amended, and increased emphasis on management of non-game species have resulted in efforts to recover remnant populations of the red-cockaded woodpecker in many parts of its historic range. Due to extensive research and adaptive management initiatives …


Tall Shrub Dynamics In Northern Minnesota Aspen And Conifer Forests, J.C. Balogh, D.F. Grigal Jan 1988

Tall Shrub Dynamics In Northern Minnesota Aspen And Conifer Forests, J.C. Balogh, D.F. Grigal

Aspen Bibliography

Tall shrubs are a dynamic component of upland forests in the Lake States (Balogh 1983, Dunn 1986, Ohmann and Ream 1971). They are an integral part of forest element cycles, competitors with overstory for growth and reproduction, essential to post-harvest site stabilization, and a source of wildlife cover and browse (Comerford and White 1977, Dunn 1986, Robinette 1972, Tappeiner 1971).