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Thermal Patterns Constrain Diurnal Behavior Of A Ground-Dwelling Bird, J. Matthew Carroll, Craig A. Davis, R. Dwayne Elmore, Samuel D. Fuhlendorf, Eric T. Thacker

Wildland Resources Faculty Publications

Recently, gaining knowledge about thermal refuges for vulnerable species has been a major focal point of ecological studies, and this focus has been heightened by predicted temperature increases associated with global climate change. To better understand how organisms respond to thermal landscapes and extremes, we investigated the thermal ecology of a gallinaceous bird species (northern bobwhite; Colinus virginianus, hereafter bobwhite) during a key life history period. Specifically, our study focused on the brood-rearing period of precocial bobwhite chicks associated with brood-attending adults. We measured site-specific black bulb temperatures (Tbb) and vegetation characteristics across 38 brood tracking days and 68 random …

Shorebird Migration In The Face Of Climate Change, Ryan J. Stutzman, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Changes in temperature and seasonality resulting from climate change are heterogeneous, potentially altering important sources of natural selection acting on species phenology. Some species have apparently adapted to climate change but the ability of most species to adapt remains unknown. The life history strategies of migratory animals are dictated by seasonal factors, which makes these species particularly vulnerable to heterogeneous changes in climate and phenology. Here, we examine the phenology of migratory shorebirds, their habitats, and primary food resources, and we hypothesize how climate change may affect migrants through predicted changes in phenology. Daily abundance of shorebirds at stopover sites …

Correlation Analysis Of Climatic Variables, Migration And Dengue Cases In Southeast Florida, Brunilda Lugo

Walden Dissertations and Doctoral Studies

Dengue fever is a debilitating, viral, mosquito-borne disease occurring in tropical and subtropical areas in the world. The majority of dengue cases in the United States were acquired in endemic areas by travelers or immigrants. However, in recent years, autochthonous (locally acquired) dengue cases have been diagnosed in Florida. The purpose of this study was to find an association between potential risk factors and the expansion of dengue fever in the United States. Guided by the eco-bio-social framework, which offers a broad assessment of risk factors for the illness, a retrospective design was used with archival data to correlate changes …

Breeding Time In A Migratory Songbird Is Predicted By Drought Severity And Group Size, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

Global climate change is altering the breeding phenology of many organisms, and one reported consequence of warmer average temperatures is earlier breeding times in migratory songbirds of north temperate latitudes. Less studied are the potential interactions between earlier breeding and social behavior in colonial species. We investigated how breeding time, as measured by colony initiation dates across the entire summer, in Cliff Swallows (Petrochelidon pyrrhonota) of southwestern Nebraska, USA, changed over a 30-year period and could be predicted by climatic variables, year, and colony size. Mean colony initiation date became earlier over the study, with variation best predicted …

Can Fire Atlas Data Improve Species Distribution Model Projections?, Shawn M. Crimmins, Solomon Z. Dobrowski, Alison R. Mynsberge, Hugh D. Safford

Forest Management Faculty Publications

Correlative species distribution models (SDMs) are widely used in studies of climate change impacts, yet are often criticized for failing to incorporate disturbance processes that can influence species distributions. Here we use two temporally independent data sets of vascular plant distributions, climate data, and fire atlas data to examine the influence of disturbance history on SDM projection accuracy through time in the mountain ranges of California, USA. We used hierarchical partitioning to examine the influence of fire occurrence on the distribution of 144 vascular plant species and built a suite of SDMs to examine how the inclusion of fire-related predictors …

Implications Of Climate Change On The Distribution Of The Tick Vector Ixodes Scapularis And Risk For Lyme Disease In The Texas-Mexico Transboundary Region, Teresa Patricia Feria-Arroyo, Ivan Castro-Arellano, Guadalupe Gordillo Pérez, Ana L. Cavazos, Margarita Vargas-Sandoval, Abha Grover, Javier Torres, Raul F. Medina, Adalberto A. Pérez De León, Maria Dolores Esteve-Gassent

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Background: Disease risk maps are important tools that help ascertain the likelihood of exposure to specific infectious agents. Understanding how climate change may affect the suitability of habitats for ticks will improve the accuracy of risk maps of tick-borne pathogen transmission in humans and domestic animal populations. Lyme disease (LD) is the most prevalent arthropod borne disease in the US and Europe. The bacterium Borrelia burgdorferi causes LD and it is transmitted to humans and other mammalian hosts through the bite of infected Ixodes ticks. LD risk maps in the transboundary region between the U.S. and Mexico are lacking. Moreover, …

Migration Plasticity As An Adaptation To Climate Change: The Spatial Distribution And Abundance Of A Subset Of Neotropical Migrant Landbirds Wintering In The Northeastern United States, Juliette Goulet

Dissertations, Theses, and Capstone Projects

There is a need for accurate predictions of the effects of climate change on wildlife populations. Bioclimatic relationships however are potentially complicated by various environmental factors operating at multiple spatial and temporal scales. Therefore, in order to test the hypothesis that climate constraints of winter bird distributions are modified by species-specific responses to weather and climate, I relied on Christmas Bird Count data (CBC). With nearly 100 years of data, the CBC is a valuable source of information on historic and recent changes in the status and distribution of birds during the early winter period in the United States and …

Effects Of River Current Inflow On Dissolved Oxygen And Temperature Of Refuge Zones For Cisco In Lake Bemidji, Bryant C. Swenson

Journal of Earth and Life Science

The objectives of this study were to (1) determine if the inflow current from the Mississippi River affects temperature and dissolved oxygen in Lake Bemidji, (2) determine how the amount of suitable cisco Coregonus artedi habitat changes over the summer in Lake Bemidji, and (3) predict how much cisco habitat would be available under a climate warming scenario. Summer fish kill of cisco occurs in most years on Lake Bemidji resulting from low dissolved oxygen in the hypolimnion and high water temperatures in the epilimnion. Dissolved oxygen and temperature profiles provided evidence to suggest the north basin is more suitable …

Temporal Ecology In The Anthropocene, E. M. Wolkovich, B. I. Cook, K. K. Mclauchlan, T. J. Davies

United States National Aeronautics and Space Administration: Publications

Two fundamental axes – space and time – shape ecological systems. Over the last 30 years spatial ecology has developed as an integrative, multidisciplinary science that has improved our understanding of the ecological consequences of habitat fragmentation and loss. We argue that accelerating climate change – the effective manipulation of time by humans – has generated a current need to build an equivalent framework for temporal ecology. Climate change has at once pressed ecologists to understand and predict ecological dynamics in non-stationary environments, while also challenged fundamental assumptions of many concepts, models and approaches. However, similarities between space and time, …

Fundamental Principles Of Law For The Anthropocene?, Nicholas A. Robinson

Elisabeth Haub School of Law Faculty Publications

A wide array of questions arises from global change to confront environmental law. The IPCC has examined social decisions affecting the climate in the design of human settlements, transport systems, industrialisation, agriculture and silviculture, waste management, provisions for energy, and virtually all other socio-economic dimensions of human life. The AR-5, too, cannot avoid raising issues of human ethics and values at local and regional scales. Such issues reach environmental policy and law directly. The IPCC’s AR-5 report furthers widespread public debate about the human dimensions of climate change, and how social theory relates to environmental change. Already, climate change has …

Finding Them Before They Find Us: Informatics, Parasites, And Environments In Accelerating Climate Change, Daniel R. Brooks, Eric P. Hoberg, Walter A. Boeger, Scott Lyell Gardner, Kurt E. Galbreath, David Herczeg, Hugo H. Mejía-Madrid, S. Elizabeth Rácz, Altangerel Tsogtsaikhan Dursahinhan

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Parasites are agents of disease in humans, livestock, crops, and wildlife and are powerful representations of the ecological and historical context of the diseases they cause. Recognizing a nexus of professional opportunities and global public need, we gathered at the Cedar Point Biological Station of the University of Nebraska in September 2012 to formulate a cooperative and broad platform for providing essential information about the evolution, ecology, and epidemiology of parasites across host groups, parasite groups, geographical regions, and ecosystem types. A general protocol, documentation–assessment–monitoring–action (DAMA), suggests an integrated proposal to build a proactive capacity to understand, anticipate, and respond …

Factors Determining Mortality Of Adult Chaparral Shrubs In An Extreme Drought Year In California, William A. S. Paddock Iii, Stephen D. Davis, R. Brandon Pratt, Anna L. Jacobsen, Michael F. Tobin, Jorge López-Portillo, Frank W. Ewers

Aliso: A Journal of Systematic and Floristic Botany

We measured dieback and mortality in a chaparral shrub community at a chaparral/desert ecotone following four years of below-average rainfall. Ecotones are important systems in which to examine plant and community responses to extreme and prolonged drought conditions and the potential impact of global change on plant distributions and community composition. Following a particularly severe drought year, dieback and mortality were documented for seven co-dominant shrub species. We examined whether mortality was related to species ecology, leaf traits, or water relations. Dieback and mortality were greatest in two non-sprouting species. These species also had high xylem cavitation resistance and low …

Climate Change Effects On Vibrio Bacteria In The Winyah Bay Estuary And The Projected Spread Of Vibrio Under Future Climatic Scenarios., Reem Deeb

Theses and Dissertations

While there are several studies on the distribution ofVibrio vulnificusandVibrio parahaemolyticusin estuarine waters around the world, there is little information on the distribution of both organisms in South Carolina waters. Monthly sampling of surface and bottom water from 9 sites in Winyah Bay was conducted over the period April-October 2012. Both organisms were enumerated on CHROMagarVibriomedia. TheVibriocounts obtained were mainly less than 20 Colony Forming Units (CFU)/ml which is typical for what was found elsewhere along the coast of the Carolinas. TheVibrio vulnificuscounts were the highest when salinity ranged between 5 ppt and 20 ppt.Vibrio parahaemolyticusdid not show a clear …

The Importance Of The Rare: The Role Of Background Symbiodinium In The Response Of Reef Corals To Environmental Change, Rachel N. Silverstein

Open Access Dissertations

Reef ecosystems throughout much of the tropics are predicted to decline in coral cover and diversity as a result of ongoing climate change (ocean acidification, temperature increases, sea level rise), disease, pollution, and overfishing. Corals may be able to respond to some of these stressors by associating with diverse algal symbionts (Symbiodinium spp.) which vary in their physiological traits and therefore expand corals’ realized niche space. This dissertation used high-sensitivity molecular techniques to investigate the presence and functional role of "background" or "rare" Symbiodinium, which occur at low abundance, and therefore may not be detected using standard molecular methods. First, …

Epiphytes: A Study Of The History Of Forest Canopy Research, Sven Batke

The Plymouth Student Scientist

The development of new and more versatile access techniques is a major contributor to the continuously growing field of canopy research. Methods such as cranes, canopy walkways, hot-air balloons, ladders and rope access techniques enabled scientist for the first time to conduct proximate studies of canopy organisms. One of the most studied groups of canopy dwellers are epiphytes. With their versatile adaptations to a life above ground level and their vast abundance, epiphytes contribute profoundly to the forest diversity and ecosystem processes. Most epiphytes have species-specific habitat preference within individual phorophytes. However these preferences are limited by biotic and abiotic …

The Impact Of Decadal Land Cover Change On The Global Warming Potential Of Beringian Arctic Tundra, David Hwei-Len Lin

Open Access Theses & Dissertations

Arctic terrestrial ecosystems play an important role in the global carbon cycle. If arctic warming continues to rise as projected, large amounts of soil carbon stored in these ecosystems could be released to the atmosphere as carbon dioxide or methane and positively enhance greenhouse warming. Thus, improving understanding of the likely future state and fate of arctic soil carbon, and the carbon uptake potential of arctic terrestrial ecosystems are well recognized research priorities.

At the pan-arctic scale, decadal increases in NDVI (Normalized Difference Vegetation Index), an index of vegetation productivity, have been observed from satellite imagery, indicating a general greening …

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …

Potential Effects Of Altered Precipitation Regimes On Primary Production In Terrestrial Ecosystems, Joanna S. Hsu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In addition to causing an increase in mean temperatures, climate change is also altering precipitation regimes across the globe. General circulation models project both latitude-dependent changes in precipitation mean and increases in precipitation variability. These changes in water availability will impact terrestrial primary productivity, the fixation of carbon dioxide into organic matter by plants. In my thesis, I addressed the following three questions: 1.) What will be the relative effect of changes in the mean and standard deviation of annual precipitation on mean annual primary production? 2.) Which ecosystems will be the most sensitive to changes in precipitation? 3.) Will …

Severe 2010 Cold-Water Event Caused Unprecedented Mortality To Corals Of The Florida Reef Tract And Reversed Previous Survivorship Patterns, Diego Lirman, Stephanie Schopmeyer, Derek Manzello, Lewis J. Gramer, William F. Precht, Frank E. Muller-Karger, Kenneth Banks, Brian Barnes, Erich Bartels, Amanda Bourque, James Byrne, Scott Donahue, Janice Duquesnel, Louis Fisher, David S. Gilliam, James C. Hendee, Meaghan E. Johnson, Kerry Maxwell, Erin Mcdevitt, Jamie Monty, Digna Rueda, Rob Ruzicka, Sara Thanner

Marine & Environmental Sciences Faculty Articles

Background

Coral reefs are facing increasing pressure from natural and anthropogenic stressors that have already caused significant worldwide declines. In January 2010, coral reefs of Florida, United States, were impacted by an extreme cold-water anomaly that exposed corals to temperatures well below their reported thresholds (16°C), causing rapid coral mortality unprecedented in spatial extent and severity.

Methodology/Principal Findings

Reef surveys were conducted from Martin County to the Lower Florida Keys within weeks of the anomaly. The impacts recorded were catastrophic and exceeded those of any previous disturbances in the region. Coral mortality patterns were directly correlated to in-situ and satellite-derived …

The Fate Of Alpine Species In The Face Of Climate Change: A Biogeographic Perspective, Madaline Cochrane

Macalester Reviews in Biogeography

Will global climate change affect the spatial distribution and abundance of biodiversity along mountains equally? The elevational gradients inherent as one moves up a mountain slope help define the many biological patterns that emerge as key indicators for species richness in an era of rising global temperatures. When global temperatures arise, the microclimates found along different elevational ranges on mountains also fluctuate. As abiotic characteristics such as daily air temperature, daily precipitation, and annual snowmelt change overtime, so will the biotic communities on a mountain. Some species may be able to adapt to their new environments, while other may have …

Assisted Migration: A Viable Conservation Strategy To Preserve The Biodiversity Of Threatened Island Nations?, Jessica A. Wentz

Sabin Center for Climate Change Law

Anthropogenic climate change poses a substantial threat to biodiversity. The IPCC estimates that 20-30% of species will face an increased risk of extinction if the average global temperature rises more than 1.5 to 2.5 degrees Celsius. Additional scientific studies indicate that 15-37% of species may become extinct by 2050 due to global warming, based on current emissions trajectories. Domestic and international strategies to manage this threat have traditionally focused on conservation and mitigation. In the last few years, however, policy makers have recognized that near-term climate impacts are inevitable and thus adaptation strategies are required to protect both humans and …

Distributed Graduate Seminars: An Interdisciplinary Approach To Studying Land Conservation, Jessica Owley, Adena R. Rissman

Articles

No abstract provided.

Demographic Response Of American Ginseng (Panax Quinquefolius L.) To Climate Change, Sara Souther

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ecological response to recent climate change has been documented for a multitude of species worldwide. Climate models predict further increases in temperature, as much as 8 times the degree of warming that has already occurred. Given observations of species response to contemporary climate change and the unprecedented degree of warming expected over the next century, climate change will no doubt determine future ecosystem composition and affect global species diversity. In order to prevent loss of biodiversity, it is necessary to understand and accurately project species' response to climate, and to identify species that are vulnerable to climate change driven extinctions. …

Heat Waves Measured With Modis Land Surface Temperature Data Predict Changes In Avian Community Structure, Thomas P. Albright, Anna M. Pidgeon, Chadwick D. Rittenhouse, Murray K. Clayton, Curtis H. Flather, Patrick D. Culbert, Volker C. Radeloff

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

Heat waves are expected to become more frequent and severe as climate changes, with unknown consequences for biodiversity. We sought to identify ecologically-relevant broad-scale indicators of heat waves based on MODIS land surface temperature (LST) and interpolated air temperature data and assess their associations with avian community structure. Specifically, we asked which data source, time periods, and heat wave indices best predicted changes in avian abundance and species richness. Using mixed effects models, we analyzed associations between these indices and data from the North American Breeding Bird Survey in the central United States between 2000 and 2007 in four ecoregions …

Twenty-Eight Years Of The Us-Lter Program: Experience, Results, And Research Questions, James R. Gosz, Robert B. Waide, John J. Magnuson

Long Term Ecological Research Network

The U.S. Long Term Ecological Research program (hereafter US-LTER) concentrates on ecological processes that play out at the time scales spanning decades to centuries. This focuses US-LTER research between the most common time scales for ecological studies (1-3 years; Tilman 1989; Figure 1) and the much longer temporal fact of disciplines such as paleoecology. The importance of the decade-to-century time scale is particularly evident in light of the rapid changes in ecological forcing functions that are occurring at a broad range of spatial scales (Millennium Ecosystem Assessment 2005, Intergovernmental Panel on Climate Change 2007). Long-term data sets from programs such …

Climate Change: Implications For Montane Mammals Of The Great Basin, Georgina Yvette Jacquez

Master's Theses or Doctor of Nursing Practice

Climate change threatens biodiversity; in particular, species with narrow distributions and specific habitat requirements. The Great Basin provides an excellent model system to evaluate the effects of climate change on species with isolated distributions and specific habitat requirements. I have evaluated the McDonald and Brown (1992) model that examined the effects of climate change on montane mammals of the Great Basin based on its underlying assumptions and model predictions. I have modeled the distributions of twelve montane mammal species found in the Great Basin and identified potential local extinctions by using maximum entropy modeling (Maxent) for two emission scenarios of …

Organismal Climatology: Analyzing Environmental Variability At Scales Relevant To Physiological Stress, Brian Helmuth, Bernardo R. Broitman, Lauren Yamane, Sarah E. Gilman, Katharine Mach, K. A.S. Mislan, Mark W. Denny

Faculty Publications

Predicting when, where and with what magnitude climate change is likely to affect the fitness, abundance and distribution of organisms and the functioning of ecosystems has emerged as a high priority for scientists and resource managers. However, even in cases where we have detailed knowledge of current species’ range boundaries, we often do not understand what, if any, aspects of weather and climate act to set these limits. This shortcoming significantly curtails our capacity to predict potential future range shifts in response to climate change, especially since the factors that set range boundaries under those novel conditions may be different …

Latitudinal Variation In Seasonal Activity And Mortality In Ratsnakes (Elaphe Obsoleta), Jinelle H. Sperry, Gabriel Blouin-Demers, Gerardo L.F. Carfagno, Patrick J. Weatherhead

Biology Faculty Publications

The ecology of ectotherms should be particularly affected by latitude because so much of their biology is temperature dependent. Current latitudinal patterns should also be informative about how ectotherms will have to modify their behavior in response to climate change. We used data from a total of 175 adult black ratsnakes (Elaphe obsoleta) radio tracked in Ontario, Illinois, and Texas, a latitudinal distance of > 1500 km, to test predictions about how seasonal patterns of activity and mortality should vary with latitude. Despite pronounced differences in temperatures among study locations, and despite ratsnakes in Texas not hibernating and switching from diurnal …

August Stream Discharge Trends Portend Impacts Of Climate Change In The Northern Rockies, Jason Christopher Leppi

Graduate Student Theses, Dissertations, & Professional Papers

This thesis is composed of two potential professional papers written to be independent of each other. Both papers were written to explore changes in late summer discharge patterns across the Northern Rockies (NR). Water in the interior western United States is a vital resource and the demand for this resource has increased. Watersheds in the NR are mainly snowmelt dominated in that they depend on the seasonal flux of snow-melt during dry periods. During the summer months August is a critical time for aquatic ecosystems due to typical low discharge and warm air temperatures. During this period water temperatures can …

Locomotion In Response To Shifting Climate Zones: Not So Fast, Martin E. Feder, Theodore Garland Jr., James H. Marden, Anthony J. Zera

School of Biological Sciences: Faculty Publications

Although a species’ locomotor capacity is suggestive of its ability to escape global climate change, such a suggestion is not necessarily straightforward. Species vary substantially in locomotor capacity, both ontogenetically and within/among populations, and much of this variation has a genetic basis. Accordingly, locomotor capacity can and does evolve rapidly, as selection experiments demonstrate. Importantly, even though this evolution of locomotor capacity may be rapid enough to escape changing climate, genetic correlations among traits (often due to pleiotropy) are such that successful or rapid dispersers are often limited in colonization or reproductive ability, which may be viewed as a trade-off. …