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Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending January 31, 2011, Margaret N. Rees
Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending January 31, 2011, Margaret N. Rees
Limnological Studies
Project 1
- Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. During this quarter, analysis was completed for 21 adult/juvenile samples and analyses of the remaining samples are underway. A manuscript describing the I-MAP and its history, current recommended monitoring, and recommended future monitoring and a separate manuscript describing the I-MAP’s monitoring protocol were accepted for publication in the journal Aquatic Invasions. Two other manuscripts describing other aspects of the I-MAP program were published in Lake and Reservoir Management.
Project 2
- Annual summary sheets are under development for the topics listed within …
Let It Be, Char Miller
2010 Vegetation Survey Of The Fort Niobrara National Wildlife Refuge (Final Report To The Nebraska Game And Parks Commission, U.S. Fish And Wildlife Service, And The Sandhills Prairie Refuge Association), Robert F. Steinauer
Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts
Fort Niobrara National Wildlife Refuge (FNNWR) is located on the Niobrara River in north central Cherry County, NE. There is little detailed information available documenting the vegetation of FNNWR. Tolstead (1942) studied the grasslands of northern Cherry County, (including FNNWR) with a focus on describing the dominant species of grassland types and determining the relationships between vegetation distribution and environmental variables and management practices. Churchill et al (1988) described the vascular flora of The Nature Conservancy’s nearby Niobrara Valley Preserve. Fiest et al (2010) conducted vascular plant surveys on portions of the FNNWR in 2009 and compiled a partial vascular …
Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian
Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian
Environmental Science and Geology Faculty Research Publications
Dreissenid bivalves, Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel) are biofouling species that invaded the Great Lakes region of North America from source populations in Europe in the 1980s. Initially, D. polymorpha spread faster and farther; however, D. bugensis have recently displaced D. polymorpha in many areas of the Great Lakes and was the first to be found west of the Continental Divide. Early detection of dreissenids is important in anticipating and preventing potentially high economic impacts. To study population dynamics and to enhance detection methods, we assessed “spawnability” using a serotonin bioassay and developed a new, sensitive, …
Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending January 10, 2011, Margaret N. Rees
Walking Box Ranch Planning And Design Quarterly Progress Report: Period Ending January 10, 2011, Margaret N. Rees
Walking Box Ranch
- UNLV participated in three project workshops and one additional meeting to assist in planning and design of the future WBR museum and field/research station.
- Weather station progress included design of programming software that will provide past weather information to website user, two abstracts have been submitted to an energy sustainability meeting, and a paper reviewing energy efficient building envelope components has been prepared and submitted for publication.
- Work has begun on a new education project titled “Multimedia Field Guides for Public Engagement at Walking Box Ranch, Mojave Desert.” The project will develop and disseminate a modern geological and environmental field …
Nitrous Oxide Emission From Denitrification In Stream And River Networks, Jake J. Beaulieu, Clay P. Arango
Nitrous Oxide Emission From Denitrification In Stream And River Networks, Jake J. Beaulieu, Clay P. Arango
All Faculty Scholarship for the College of the Sciences
Nitrous oxide (N2O) is a potent greenhouse gas that contributes to climate change and stratospheric ozone destruction. Anthropogenic nitrogen (N) loading to river networks is a potentially important source of N2O via microbial denitrification that converts N to N2O and dinitrogen (N2). The fraction of denitrified N that escapes as N2O rather than N2 (i.e., the N2O yield) is an important determinant of how much N2O is produced by river networks, but little is known about the N2O yield in flowing waters. Here, …
Synthesis Of Knowledge Of Extreme Fire Behavior: Volume I For Fire Managers, Paul Werth, Brian Potter, Craig Clements, Mark Finney, Scott Goodrick, Martin Alexander, Miguel Cruz, Jason Forthofer, Sara Mcallister
Synthesis Of Knowledge Of Extreme Fire Behavior: Volume I For Fire Managers, Paul Werth, Brian Potter, Craig Clements, Mark Finney, Scott Goodrick, Martin Alexander, Miguel Cruz, Jason Forthofer, Sara Mcallister
Faculty Publications, Meteorology and Climate Science
The National Wildfire Coordinating Group definition of extreme fire behavior (EFB) indicates a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning/ spotting, presence of fire whirls, and strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously. Alternate terms include “blow up” and “fire storm.” Fire managers examining fires over the last 100 years have come to understand many of the factors necessary for EFB development. This …
Multidecadal Otolith Growth Histories For Red And Gray Snapper (Lutjanus Spp.) In The Northern Gulf Of Mexico, Usa, Bryan A. Black, Robert J. Allman, Isaac D. Schroeder, Michael J. Schirripa
Multidecadal Otolith Growth Histories For Red And Gray Snapper (Lutjanus Spp.) In The Northern Gulf Of Mexico, Usa, Bryan A. Black, Robert J. Allman, Isaac D. Schroeder, Michael J. Schirripa
United States Department of Commerce: Staff Publications
Dendrochronology (tree-ring analysis) techniques were applied to develop chronologies from the annual growth-increment widths of red snapper (Lutjanus campechanus) and gray snapper (Lutjanus griseus) otoliths sampled from the northern Gulf of Mexico, USA. Growth increment widths showed considerable synchrony within and across species, indicating that some component of environmental variability influenced growth. The final, exactly dated red snapper chronology continuously spanned 1975 through 2003, while the gray snapper chronology continuously spanned 1975 through 2006. To determine baseline climategrowth relationships, chronologies were compared to monthly averages of sea surface temperatures, U winds (west to east), V winds …
The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds [Presentation], Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College
The Missing Link: The Ecology Of The Serpentine And The Implications For East And North Ponds [Presentation], Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College
Colby College Watershed Study: East and North Ponds (2011, 1999, 1996, 1991)
No abstract provided.
Climate Change And San Francisco Bay-Delta Tidal Wetlands, V Thomas Parker, John Callaway, Lisa M. Schile, Michael C. Vasey, Ellen R. Herbert
Climate Change And San Francisco Bay-Delta Tidal Wetlands, V Thomas Parker, John Callaway, Lisa M. Schile, Michael C. Vasey, Ellen R. Herbert
Environmental Science
Climate change will affect tidal wetlands with higher rates of sea-level rise and higher concentrations of salt in brackish and freshwater tidal systems, in addition to causing increases in atmospheric CO2 concentration, warmer temperatures, and shifts in precipitation. In the San Francisco Bay–Delta, the areas most likely to be affected—brackish and freshwater tidal wetlands—are also the sites with the majority of endemic plant species and the greater biodiversity and productivity. Effects on the San Francisco Bay– Delta estuary are complex and difficult to predict, but a few things are clear. Biodiversity of the tidal wetland system in the San Francisco …
Stormwater Management: Terminology, Kathryn A. Pekarek, David P. Shelton, Kelly Feehan, Bobbi A. Holm
Stormwater Management: Terminology, Kathryn A. Pekarek, David P. Shelton, Kelly Feehan, Bobbi A. Holm
School of Natural Resources: Faculty Publications
Stormwater runoff is the result of precipitation that does not infiltrate into the soil. Rather, it flows over land areas or through storm drains to streams, rivers, and lakes. This water collects pollutants as it moves over streets, parking lots, driveways, and other surfaces. Typically, stormwater runoff is untreated before being discharged to surface water. The quantity and quality of stormwater runoff is directly related to land use; as more urban development occurs — especially impervious surfaces — greater amounts of water and contaminants are generated. According to the U.S. Environmental Protection Agency (EPA), highly urbanized areas generate over five …
Nest Survival Of Long-Billed Curlew In Nebraska, Cory J. Gregory, Stephen J. Dinsmore, Larkin A. Powell, Joel G. Jorgensen
Nest Survival Of Long-Billed Curlew In Nebraska, Cory J. Gregory, Stephen J. Dinsmore, Larkin A. Powell, Joel G. Jorgensen
School of Natural Resources: Faculty Publications
Long-billed Curlew Numenius americanus is an imperiled shorebird of western North America. Populations have declined dramatically in the last 150 years from the conversion of prairie to agriculture and it is now listed as a “Tier I at-risk” species in Nebraska. We undertook a 3-year project (2008–2010) to study the nest survival of Long-billed Curlews in Nebraska. We measured vegetation characteristics at each nest site (n = 14 nests) on two different spatial scales and used program MARK to model nest survival as a function of multiple covariates. Apparent nest survival was 29% (n = 4 successful nests) and our …
The Influence Of Habitat And Environment On Smallmouth Bass (Micropterus Dolomieu) Nest Sites And Nest Success In Northern Lake Michigan, Mark A. Kaemingk, Alexander Clem, Tracy L. Galarowicz
The Influence Of Habitat And Environment On Smallmouth Bass (Micropterus Dolomieu) Nest Sites And Nest Success In Northern Lake Michigan, Mark A. Kaemingk, Alexander Clem, Tracy L. Galarowicz
School of Natural Resources: Faculty Publications
Information on smallmouth bass nesting ecology is lacking in northern Lake Michigan, despite available information for other Great Lakes ecosystems. Our objectives were to identify factors that influenced nesting sites and nest success in a smallmouth bass population in northern Lake Michigan. Temperature, substrate firmness, and lake bottom rugosity were measured and related to the number of smallmouth bass nests in four bays. We also investigated the role of temperature, effective fetch, and storms to explain nest success. Temperature appeared to be most important in explaining the number of nests and nest success; transects that experienced the greatest number of …
Movement Of Smallmouth Bass Within The Beaver Island Archipelago, Northern Lake Michigan., Mark A. Kaemingk, Tracy L. Galarowicz, John A. Clevenger, David F. Clapp
Movement Of Smallmouth Bass Within The Beaver Island Archipelago, Northern Lake Michigan., Mark A. Kaemingk, Tracy L. Galarowicz, John A. Clevenger, David F. Clapp
School of Natural Resources: Faculty Publications
Fish movement may vary across a wide array of aquatic ecosystems and may be related to the overall size of the system inhabited. We investigated movement of smallmouth bass in Lake Michigan because this information is lacking for larger systems. A total of 16 smallmouth bass were surgically implanted with ultrasonic transmitters within the Beaver Archipelago, northern Lake Michigan. During 2007–2008, a maximum of one location per individual was recorded daily during three specific tracking periods – pre-spawn, spawning, and post-spawn – to determine diurnal movement patterns. Movement was evaluated as site fidelity, minimum displacement rate,maximumexcursion rate, and distance from …
Exploring Spatial Distributions Of Larval Yellow Perch Perca Flavescens, Bluegill Lepomis Macrochirus, And Their Prey In Relation To Wind., Mark A. Kaemingk, Jeffrey C. Jolley, David W. Willis, Brian Ds Graeb
Exploring Spatial Distributions Of Larval Yellow Perch Perca Flavescens, Bluegill Lepomis Macrochirus, And Their Prey In Relation To Wind., Mark A. Kaemingk, Jeffrey C. Jolley, David W. Willis, Brian Ds Graeb
School of Natural Resources: Faculty Publications
The objectives of the present study were to determine if spatial differences existed between zooplankton, larval yellow perch Perca flavescens and bluegill Lepomis macrochirus (length, LT) in Pelican Lake (332 ha), NE, U.S.A. It was hypothesized that wind could act as a transport mechanism for larval fishes in this shallow lake, because strong winds are common at this geographic location. Potential spatial differences were explored, relating to zooplankton densities, size structure and densities of larval P. flavescens and L. macrochirus. Density differences (east v. west side of the lake) were detected for small- (two occasions), medium- (two occasions) and large-sized …
Discovering Native Bees, Alison P. Stevens
Discovering Native Bees, Alison P. Stevens
School of Natural Resources: Faculty Publications
NATURAL SYSTEMS PROVIDE humans with a variety of services essential to our survival. Ecosystem services such as climate regulation, water purification, oxygen production, waste treatment and detoxification, flood prevention, and pollination are provided at no cost, yet their true value is immeasurable. In our economydriven world, these systems are often taken for granted, and as a consequence many are in peril. Understanding their role is a critical first step towards ensuring that they endure. Pollination, the process of moving pollen grains from one flower to another to stimulate fruit and seed production, is among the easiest of these services to …
An Interannual Assessment Of The Relationship Between The Stable Carbon Isotopic Composition Of Ecosystem Respiration And Climate In A High‐Elevation Subalpine Forest, Diego Andrés Riveros-Iregui, Jia Hu, Sean Burns, David R. Bowling, Russell K. Monson
An Interannual Assessment Of The Relationship Between The Stable Carbon Isotopic Composition Of Ecosystem Respiration And Climate In A High‐Elevation Subalpine Forest, Diego Andrés Riveros-Iregui, Jia Hu, Sean Burns, David R. Bowling, Russell K. Monson
School of Natural Resources: Faculty Publications
We measured the carbon isotopic composition (δ13C) of ecosystem respiration (δ13CR) in a subalpine forest across four growing seasons to examine whether patterns in δ13CR were consistent with those expected based on leaf‐level gas‐exchange theory, and in agreement with past studies of the relation between δ13CR and climate conducted across broad geographic regions. Conventional trends (i.e., less negative δ13CR with increased vapor pressure deficit (VPD) and air temperature (TAIR), and decreased soil moisture (θ)) were observed when we focused on the driest portions …
Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre
Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre
School of Natural Resources: Faculty Publications
Wildlife managers often make decisions under considerable uncertainty. In the most extreme case, a complete lack of data leads to uncertainty that is unquantifiable.Information-gap decision theory deals with assessing management decisions under extreme uncertainty, but it is not widely used in wildlife management. So too, robust population management methods were developed to deal with uncertainties in multiple-model parameters.However, the two methods have not, as yet, been used in tandem to assess population management decisions. We provide a novel combination of the robust population management approach for matrix models with the information-gap decision theory framework for making conservation decisions under extreme …
Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels
Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels
School of Natural Resources: Faculty Publications
As more and more organizations with responsibility for natural resource management adopt adaptive management as the rubric in which they wish to operate, it becomes increasingly important to consider the sources of uncertainty inherent in their endeavors. Without recognizing that uncertainty originates both in the natural world and in human undertakings, efforts to manage adaptively at the least will prove frustrating and at the worst will prove damaging to the very natural resources that are the management targets. There will be more surprises and those surprises potentially may prove at the very least unwanted and at the worst devastating. We …
Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre
Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre
School of Natural Resources: Faculty Publications
Within the field of natural-resources management, the application of adaptive management is appropriate for complex problems high in uncertainty. Adaptive management is becoming an increasingly popular management-decision tool within the scientific community and has developed into two primary schools of thought: the Resilience-Experimentalist School (with high emphasis on stakeholder involvement, resilience, and highly complex models) and the Decision-Theoretic School (which results in relatively simple models through emphasizing stakeholder involvement for identifying management objectives). Because of these differences, adaptive management plans implemented under each of these schools may yield varying levels of success. We evaluated peer-reviewed literature focused on incorporation of …
Review Of Mammalian Teeth: Origin, Evolution, And Diversity By Peter S. Ungar, Patricia W. Freeman
Review Of Mammalian Teeth: Origin, Evolution, And Diversity By Peter S. Ungar, Patricia W. Freeman
School of Natural Resources: Faculty Publications
Peter Ungar has written a book on mammalian teeth, a topic close to the heart of mammalogy itself and most mammalogists. His distillation of the massive literature on teeth into a succinct whole will appeal to scientists and professionals across disciplines. With paleontological and extant dental research in one place I no longer have to search these areas separately to find what I want. Ungar’s broad background includes physical anthropology, anatomy, and paleontology. Further, he has been one of the pioneers using dental microwear to analyze diets in primates and geographic information systems (GISs) on a microscale to study cusps …
Seasonal Energy And Water Balance Of A Phragmites Australis-Dominated Wetland In The Republican River Basin Of South-Central Nebraska (Usa), John D. Lenters, Gregory J. Cutrell, Erkan Istanbulluoglu, Durelle T. Scott, Kyle S. Herrman, Dean E. Eisenhauer
Seasonal Energy And Water Balance Of A Phragmites Australis-Dominated Wetland In The Republican River Basin Of South-Central Nebraska (Usa), John D. Lenters, Gregory J. Cutrell, Erkan Istanbulluoglu, Durelle T. Scott, Kyle S. Herrman, Dean E. Eisenhauer
School of Natural Resources: Faculty Publications
energy and water balance, especially in dry climatic regions, can have a significant impact on local water availability and, therefore, water resource management. The purpose of this study is to quantify the energy and water balance of a riparian wetland in a subhumid region of the central US, as well as the role of seasonal climate variability and vegetation phenology. The site is located in the Republican River basin in south-central Nebraska, where decreases in streamflow have been observed in recent decades. In an effort to reduce consumptive water use from evapotranspiration (ET), and thereby reclaim surface water, invasive species …
Assessing Net Ecosystem Carbon Exchange Of U.S. Terrestrial Ecosystems By Integrating Eddy Covariance Flux Measurements And Satellite Observations, Jingfeng Xiao, Qianlai Zhuang, Beverly E. Law, Dennis D. Baldocchi, Jiquan Chen, Andrew D. Richardson, Jerry M. Melillo, Kenneth J. Davis, David Y. Hollinger, Sonia Wharton, Ram Oren, Asko Noormets, Marc L. Fischer, Shashi Verma, David R. Cook, Ge Sun, Steve Mcnulty, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, Peter S. Curtis, Bert G. Drake, Matthias Falk, David R. Foster, Lianhong Gu, Julian L. Hadley, Gabriel G. Katul, Marcy Litvak, Siyan Ma, Timothy A. Martin, Roser Matamala, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, U. Kyaw Tha Paw, Hans Peter Schmid, Russell L. Scott, Gregory Starr, Andrew E. Suyker, Margaret S. Torn
Assessing Net Ecosystem Carbon Exchange Of U.S. Terrestrial Ecosystems By Integrating Eddy Covariance Flux Measurements And Satellite Observations, Jingfeng Xiao, Qianlai Zhuang, Beverly E. Law, Dennis D. Baldocchi, Jiquan Chen, Andrew D. Richardson, Jerry M. Melillo, Kenneth J. Davis, David Y. Hollinger, Sonia Wharton, Ram Oren, Asko Noormets, Marc L. Fischer, Shashi Verma, David R. Cook, Ge Sun, Steve Mcnulty, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, Peter S. Curtis, Bert G. Drake, Matthias Falk, David R. Foster, Lianhong Gu, Julian L. Hadley, Gabriel G. Katul, Marcy Litvak, Siyan Ma, Timothy A. Martin, Roser Matamala, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, U. Kyaw Tha Paw, Hans Peter Schmid, Russell L. Scott, Gregory Starr, Andrew E. Suyker, Margaret S. Torn
School of Natural Resources: Faculty Publications
More accurate projections of future carbon dioxide concentrations in the atmosphere and associated climate change depend on improved scientific understanding of the terrestrial carbon cycle. Despite the consensus that U.S. terrestrial ecosystems provide a carbon sink, the size, distribution, and interannual variability of this sink remain uncertain. Here we report a terrestrial carbon sink in the conterminous U.S. at 0.63 pg C yr−1 with the majority of the sink in regions dominated by evergreen and deciduous forests and savannas. This estimate is based on our continuous estimates of net ecosystem carbon exchange (NEE) with high spatial (1 km) and …
Comparison And Analysis Of Empirical Equations For Soil Heat Flux For Different Cropping Systems And Irrigation Methods, Ayse Kilic, R. K. Singh, Elizabeth A. Walter-Shea, Shashi Verma, Andrew E. Suyker
Comparison And Analysis Of Empirical Equations For Soil Heat Flux For Different Cropping Systems And Irrigation Methods, Ayse Kilic, R. K. Singh, Elizabeth A. Walter-Shea, Shashi Verma, Andrew E. Suyker
School of Natural Resources: Faculty Publications
We evaluated the performance of four models for estimating soil heat flux density (G) in maize (Zea mays L.) and soybean (Glycine max L.) fields under different irrigation methods (center‐pivot irrigated fields at Mead, Nebraska, and subsurface drip irrigated field at Clay Center, Nebraska) and rainfed conditions at Mead. The model estimates were compared against measurements made during growing seasons of 2003, 2004, and 2005 at Mead and during 2005, 2006, and 2007 at Clay Center. We observed a strong relationship between the G and net radiation (Rn) ratio (G/Rn) and the normalized difference …
Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf
Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf
School of Natural Resources: Faculty Publications
Social factors, such as farming methods, have an impact on farm vulnerability to drought, but have received little research or policy attention. Some researchers and advocates have argued that sustainable agriculture systems are less vulnerable to climate risk than conventional systems because sustainable agriculture requires producers to have skills promoting adaptability. In this paper, we investigate producers’ perceptions on the use of sustainable agriculture in reducing drought risk, and what they believe would help them better adapt to drought. We surveyed and interviewed farmer members of two sustainable agriculture organizations in Nebraska, USA, during a multi-year drought period from 1999 …
Adaptive Harvest Management And Harvest Mortality Of Greater Prairie-Chickens, Larkin A. Powell, J. Scott Taylor, Ty W. Matthews
Adaptive Harvest Management And Harvest Mortality Of Greater Prairie-Chickens, Larkin A. Powell, J. Scott Taylor, Ty W. Matthews
School of Natural Resources: Faculty Publications
Adaptive harvest management (AHM) can assist biologists with decisions made under uncertainty. There have been few applications of AHM to manage wildlife at the state level, and we provide a theoretical exercise using AHM in the context of Greater Prairie-Chicken harvest in southeast Nebraska. Our goals were to develop and evaluate an AHM framework for a state specific harvest decision, and to use the AHM process to evaluate uncertainties associated with harvest mortality for Greater Prairie-Chickens in Nebraska. Harvest of prairie chickens in southeast Nebraska was restarted 2000, using a special limited permit system, and was controversial with respect to …
Estimating Nest Density When Detectability Is Incomplete: Variation In Nest Attendance And Response To Disturbance By Western Meadowlarks, Matthew D. Giovanni, Max Post Van Der Burg, Lars C. Anderson, Larkin A. Powell, Walter H. Schacht, Andrew J. Tyre
Estimating Nest Density When Detectability Is Incomplete: Variation In Nest Attendance And Response To Disturbance By Western Meadowlarks, Matthew D. Giovanni, Max Post Van Der Burg, Lars C. Anderson, Larkin A. Powell, Walter H. Schacht, Andrew J. Tyre
School of Natural Resources: Faculty Publications
Researchers commonly model nest density as a function of ecological variables, but nests, like birds, can be undetected while present. In the Nebraska Sandhills in 2007, we used the rope-drag method on previously located Western Meadowlark (Sturnella neglecta) nests to model nest-detection error and nest density. Detecting nests by rope dragging (commonly used for nests of grassland birds) is conditional on two primary sources of nest availability, adults attending nests and adults flushing from nests in response to disturbance from the rope, the behavioral cue necessary for nest detection. On the basis of our trials with rope dragging, …
Chapter Thirteen- Habitat Selection And Brood Survival Of Greater Prairie-Chickens, Ty W. Matthews, Andrew J. Tyre, J. Scott Taylor, Jeffery J. Lusk, Larkin A. Powell
Chapter Thirteen- Habitat Selection And Brood Survival Of Greater Prairie-Chickens, Ty W. Matthews, Andrew J. Tyre, J. Scott Taylor, Jeffery J. Lusk, Larkin A. Powell
School of Natural Resources: Faculty Publications
The Greater Prairie-Chicken (Tympanuchus cupido pinnatus) is a species that may benefit from conversion of crop ground to grassland through the Conservation Reserve Program (CRP). CRP grasslands could provide nesting and brood-rearing habitat, an important component of population persistence. Managers and policymakers currently lack evidence of CRP’s relative contribution to populations of Greater Prairie-Chicken. We used radiotelemetry to mark females (n =100) in southeast Nebraska, in a landscape which had >15% of land area enrolled in CRP. We examined macrohabitat and microhabitat selection of brood-rearing females (n=36) using discrete choice models, and examined the variability in brood survival …
Nest Survival Of Long-Billed Curlew In Nebraska, Cory J. Gregory, Stephen J. Dinsmore, Larkin A. Powell, Joel G. Jorgensen
Nest Survival Of Long-Billed Curlew In Nebraska, Cory J. Gregory, Stephen J. Dinsmore, Larkin A. Powell, Joel G. Jorgensen
School of Natural Resources: Faculty Publications
Long-billed Curlew Numenius americanus is an imperiled shorebird of western North America. Populations have declined dramatically in the last 150 years from the conversion of prairie to agriculture and it is now listed as a “Tier I at-risk” species in Nebraska. We undertook a 3-year project (2008–2010) to study the nest survival of Long-billed Curlews in Nebraska. We measured vegetation characteristics at each nest site (n = 14 nests) on two different spatial scales and used program MARK to model nest survival as a function of multiple covariates. Apparent nest survival was 29% (n = 4 successful nests) and our …
Fluctuation Of Hyporheic Zone Thickness Due To Inflow And Outflow Across The Water-Sediment Interface, Xunhong Chen
Fluctuation Of Hyporheic Zone Thickness Due To Inflow And Outflow Across The Water-Sediment Interface, Xunhong Chen
School of Natural Resources: Faculty Publications
Determination of hyporheic zone thickness in streams is an important step for study of stream-aquifer interactions. Knowledge about hyporheic zone thickness is useful in stream restoration. However, because there is a lack of standard techniques for such study, evaluation of the hyporheic zone thickness for a given stream reach remains a challenge task for researchers. This paper presents Galerkin finite element flow and stream function models that can simulate the hyporheic zone thickness. The flow and stream function equations are solved for 2-D profile domains that can be across a stream or parallel to a stream. The numeral schemes for …