Natural Resources and Conservation Commons^™

Temperature, Hatch Date, And Prey Availability Influence Age-0 Yellow Perch Growth And Survival, Mark A. Kaemingk, Brian D. S. Graeb, David W. Willis

School of Natural Resources: Faculty Publications

Throughout their range, Yellow Perch Perca flavescens are an important ecological and economic component of many fisheries, but they often exhibit highly variable recruitment. Much research effort has been devoted to better understanding the mechanisms responsible for these erratic recruitment patterns, yet few studies have examined this process at the detail necessary to reveal complex interactions that may exist across multiple early life stages. Our current understanding of the early life recruitment patterns of Yellow Perch suggests a strong abiotic component. Using existing information, we developed three working hypotheses to examine Yellow Perch recruitment at two larval stages (5–14 and …

Does Human Predation Risk Affect Harvest Susceptibility Of White-Tailed Deer During Hunting Season?, Andrew R. Little, Stephen Demarais, Kenneth L. Gee, Stephen L. Webb, Samuel K. Riffell, Joshua A. Gaskamp, Jerrod L. Belant

School of Natural Resources: Faculty Publications

Large carnivores are considered a primary source of mortality for many ungulate populations, but harvest by hunters is the primary means of population management. However, research is needed to evaluate how human predation risk influences observability (a surrogate to harvest susceptibility) of ungulates. We determined how hunting intensity and duration influence observation rates of white-tailed deer (Odocoileus virginianus) and how deer behavior (i.e., movement rate and resource selection) affects observation rates. We sampled 37 adult (≥2 yr) male deer at 2 levels of risk (i.e., low-risk = 1 hunter/101 ha; and high-risk = 1 hunter/30 ha) during 3 …

Unscreened Water-Diversion Pipes Pose An Entrainment Risk To The Threatened Green Sturgeon, Acipenser Medirostris, Timothy D. Mussen, Dennis Chocherell, Jamilynn B. Poletto, Jon S. Reardon, Zachary Hockett, Ali Ercan, Hossein Bandeh, M. Levent Kavvas, Joseph J. Cech Jr., Nann A. Fangue

School of Natural Resources: Faculty Publications

Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (3560.6 cm mean fork length) to entrainment in a large (.500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26–61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that …

Larval Green And White Sturgeon Swimming Performance In Relation To Water-Diversion Flows, Christine E. Verhille, Jamilynn B. Poletto, Dennis E. Cocherell, Bethany Decourten, Sarah Baird, Joseph J. Cech Jr., Nann A. Fangue

School of Natural Resources: Faculty Publications

Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento–San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations. Therefore, the aim of this study was to describe and compare …

Efficacy Of A Sensory Deterrent And Pipe Modifications In Decreasing Entrainment Of Juvenile Green Sturgeon (Acipenser Medirostris) At Unscreened Water Diversions, Jamilynn B. Poletto, Dennis E. Cocherell, Timothy D. Mussen, Ali Ercan, Hossein Bandeh, M. Levent Kavvas, Joseph J. Cech Jr., Nann A. Fangue

School of Natural Resources: Faculty Publications

Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento–San Joaquin watershed in California’s Central Valley exceeds 3300, and the majority of these are unscreened. Many anadromous fish species are susceptible to entrainment into these diversions, potentially impacting population numbers. In the laboratory, juvenile green sturgeon (Acipenser medirostris) have been shown to have high entrainment rates into unscreened diversions compared with those of other native California fish …

Parameterization Of The Satellite-Based Model (Metric) For The Estimation Of Instantaneous Surface Energy Balance Components Over A Drip-Irrigated Vineyard, Marcos Carrasco-Benavides, Samuel Ortega-Farias, Luis Octavio Lagos, Jan Kleissl, Luis Morales-Salinas, Ayse Kilic

School of Natural Resources: Faculty Publications

A study was carried out to parameterize the METRIC (Mapping EvapoTranspiration at high Resolution with Internalized Calibration) model for estimating instantaneous values of albedo (shortwave albedo) (αi), net radiation (Rni) and soil heat flux (Gi), sensible (Hi) and latent heat (LEi) over a drip-irrigated Merlot vineyard (location: 35°25′ LS; 71°32′ LW; 125 m.a.s. (l). The experiment was carried out in a plot of 4.25 ha, processing 15 Landsat images, which were acquired from 2006 to 2009. An automatic weather station was placed inside the experimental plot to measure αi, …

Biofrag – A New Database For Analyzing Biodiversity Responses To Forest Fragmentation, Marion Pfeifer, Andrew Tyre

School of Natural Resources: Faculty Publications

Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded by a lack of key statistical or methodological information. Collating primary datasets on biodiversity responses to fragmentation in a consistent and flexible database permits simple data retrieval for subsequent analyses. We present a relational database that links such field data to taxonomic nomenclature, spatial and temporal plot attributes, and environmental characteristics. Field assessments include measurements of the response(s) (e.g., presence, abundance, ground cover) of one or more species …

Spectroscopic Analysis Of Seasonal Changes In Live Fuel Moisture Content And Leaf Dry Mass, Yi Qi, Philip E. Dennison, W. Matt Jolly, Rachael C. Kropp, Simon C. Brewer

School of Natural Resources: Faculty Publications

No abstract provided.

Transdisciplinary Research On Environmental Governance: A View From The Inside, Katherine Mattor, Michele Betsill, Ch'aska Huayhuaca, Heidi Huber-Stearns, Theresa Jedd, Faith Sternlieb, Patrick Bixler, Matthew Luizza, Antony S. Cheng

School of Natural Resources: Faculty Publications

No abstract provided.

Carbon–Temperature–Water Change Analysis For Peanut Production Under Climate Change: A Prototype For The Agmip Coordinated Climate-Crop Modeling Project (C3mp), Alex Ruane, Sonali Mcdermid, Cynthia Rosenzweig, Guillermo Baigorria, James W. Jones, Consuelo Romero, L. Dewayne Cecil

School of Natural Resources: Faculty Publications

Climate change is projected to push the limits of cropping systems and has the potential to disrupt the agricultural sector from local to global scales. This article introduces the Coordinated Climate-Crop Modeling Project (C3MP), an initiative of the Agricultural Model Intercomparison and Improvement Project (AgMIP) to engage a global network of crop modelers to explore the impacts of climate change via an investigation of crop responses to changes in carbon dioxide concentration ([CO2]), temperature, and water. As a demonstration of the C3MP protocols and enabled analyses, we apply the Decision Support System for Agrotechnology Transfer (DSSAT) CROPGRO-Peanut crop model for …

Assessing Risk Of Disease Transmission: Direct Implications For An Indirect Science, Michael Lavelle, Justin Fischer, Gregory Phillips, Tyler Campbell, Kurt C. Vercauteren, Aaron Hildreth, David Hewiltt, Scott Hygnstrom

School of Natural Resources: Faculty Publications

By definition, contact denotes the ;unction of at least two objects. In the context of disease transmission, contact implies interaction with potential to spread disease. Mischaracterization of contacts may res"lt in inaccurate estimates of transmission rates. To collect more-accurate contact data among white-tailed deer (Odocoileus virginianus), "'e built a deer-borne contact detection system (DCDS) consisting of a camera and a proximity logger installed on a GPS (Global Positioning System) collar. We outfitted 26 adult male deer with DCDSs to record GPS locations, proximity of equipped deer to other equipped deer, and video of deer interactions in southern Texas during arltUmn …

A Tallgrass Prairie Forb In A Landscape Shaped By Patch Burn Grazing, Stephen L. Winter

School of Natural Resources: Faculty Publications

Our research indicated that Indian plantain is a tallgrass prairie forb that experiences a temporary period of competitive release as a result of the fire‐grazing interaction found in patch burn grazing systems. Additional research is needed to determine what other species of perennial forbs exhibit this phenomena and in what other locations. Conservationists are especially interested in whether this is the case for what are termed “conservative” species of forbs, species that aren’t typically found in locations that have a long history of heavy grazing or other type of land use that produces vegetation characterized by only the hardiest species. …

On The Role Of Budget Sufficiency, Cost Efficiency, And Uncertainty In Species Management, Max Post Van Der Burg, Bartholomew B. Bly, Tammy Vercauteren, James B. Grand, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Many conservation planning frameworks rely on the assumption that one should prioritize locations for management actions based on the highest predicted conservation value (i.e., abundance, occupancy). This strategy may underperform relative to the expected outcome if one is working with a limited budget or the predicted responses are uncertain. Yet, cost and tolerance to uncertainty rarely become part of species management plans. We used field data and predictive models to simulate a decision problem involving western burrowing owls (Athene cunicularia hypugaea) using prairie dog colonies (Cynomys ludovicianus) in western Nebraska. We considered 2 species management strategies: …

You Are Not Always What We Think You Eat: Selective Assimilation Across Multiple Whole-Stream Isotopic Tracer Studies, W. K. Dodds, S. M. Collins, S. K. Hamilton, J. L. Tank, S. Johnson, J. R. Webster, K. S. Simon, M. R. Whiles, H. M. Rantala, W. H. Mcdowell, S. D. Peterson, T. Riis, C. L. Crenshaw, S. A. Thomas, P. B. Kristensen, B. M. Cheever, A. S. Flecker, N. A. Griffiths, T. Crowl, E. J. Rosi-Marshall, R. El-Sabaawi, E. Marti

School of Natural Resources: Faculty Publications

Analyses of 21 ¹⁵N stable isotope tracer experiments, designed to examine food web dynamics in streams around the world, indicated that the isotopic composition of food resources assimilated by primary consumers (mostly invertebrates) poorly reflected the presumed food sources. Modeling indicated that consumers assimilated only 33–50% of the N available in sampled food sources such as decomposing leaves, epilithon, and fine particulate detritus over feeding periods of weeks or more. Thus, common methods of sampling food sources consumed by animals in streams do not sufficiently reflect the pool of N they assimilate. Isotope tracer studies, combined with modeling and …

Estimation Of Crop Gross Primary Production (Gpp): I. Impact Of Modisobservation Footprint And Impact Of Vegetation Brdf Characteristics, Qingyuan Zhang, Yen-Ben Cheng, Alexei I. Lyapustin, Yujie Wang, Xiangming Xiao, Andrew E. Suyker, Shashi Verma, Bin Tan, Elizabeth M. Middleton

School of Natural Resources: Faculty Publications

Accurate estimation of gross primary production (GPP) is essential for carbon cycle and climate change studies. Three AmeriFlux crop sites of maize and soybean were selected for this study. Two of the sites were irrigated and the other one was rainfed. The normalized difference vegetation index (NDVI), the enhanced vegetation index (EVI), the green band chlorophyll index (CI_green), and the green band wide dynamic range vegetation index (WDRVI_green) were computed from the moderate resolution imaging spectroradiometer (MODIS) surface reflectance data. We examined the impacts of the MODIS observation footprint and the vegetation bidirectional reflectance distribution function …

2014 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen, Lauren R. Dinan

School of Natural Resources: Faculty Publications

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2013–2014). We prepared it to inform our partners, cooperating agencies, funding sources, and other interested parties of our activities and to provide a preliminary summary of our results.

The lower Platte River and its major tributaries provide important nesting and migratory stopover habitat for two bird species of special conservation concern: the state and federally endangered Interior Least Tern (Sternula antillarum athalassos) and threatened Piping Plover (Charadrius melodus). The Tern and Plover Conservation Partnership (TPCP), based at the University of …

Spatial Accuracy Of Climate Networks: A Case Study In Nebraska, Andrea J. Coop, Kenneth Hubbard, Martha Shulski, Jinsheng You, David B. Marx

School of Natural Resources: Faculty Publications

Climate data are increasingly scrutinized for accuracy because of the need for reliable input for climaterelated decision making and assessments of climate change. Over the last 30 years, vast improvements to U.S. instrumentation, data collection, and station siting have created more accurate data. This study explores the spatial accuracy of daily maximum and minimum air temperature data in Nebraska networks, including the U.S. Historical Climatology Network (HCN), the Automated Weather Data Network (AWDN), and the more recent U.S. Climate Reference Network (CRN). The spatial structure of temperature variations at the earth’s surface is compared for timeframes 2005–09 for CRN and …

Iron Clad Wetlands: Soil Iron-Sulfur Buffering Determines Coastal Wetland Response To Salt Water Incursion, Valerie Anne Schoepfer, Emily S. Bernhardt, Amy J. Burgin

School of Natural Resources: Faculty Publications

Coastal freshwater wetland chemistry is rapidly changing due to increased frequency of salt water incursion, a consequence of global change. Seasonal salt water incursion introduces sulfate, which microbially reduces to sulfide. Sulfide binds with reduced iron, producing iron sulfide (FeS), recognizable in wetland soils by its characteristic black color. The objective of this study is to document iron and sulfate reduction rates, as well as product formation (acid volatile sulfide (AVS) and chromium reducible sulfide (CRS)) in a coastal freshwater wetland undergoing seasonal salt water incursion. Understanding iron and sulfur cycling, as well as their reduction products, allows us to …

Coupled Heat And Vapor Transport: The Thermostat Effect Of A Freely Evaporating Land Surface, Jozsef Szilagyi, Aaron Schepers

School of Natural Resources: Faculty Publications

Analytical solutions of the 2-D heat and vapor transport equations for a surface moisture jump are often based on a constant streamwise temperature (T_ws) assumption over the wet vegetated surface. By analyzing 90 thermal infrared images taken over center-pivot irrigated areas in Nebraska, it has been demonstrated for the first time that such an assumption is realistic. Average temperature difference between the perimeter and core of the irrigated full or half circles stayed between -0.11 and 0.09°C (standard deviation of 0.25–0.41°C). It was further demonstrated that wet-bulb temperatures (a proxy of T_ws) remain near constant during …

Water Metrics, Lisa-Maria Rebelo, Jean-Marc Faurès, Poolad Karimi, Wim Bastiaanssen, Meredith Giordano, Vladimir Smakhtin, Peter G. Mccornick

Daugherty Water for Food Global Institute: Faculty Publications

Society has a universal need for water that crosses all sectors of activity. We need to be able to measure progress towards sustainable water for all by working towards targets that consider the different dimensions of water resources and use, including water quantity and quality. A suite of indicators that reflect water use by different sectors is needed to measure progress towards the forthcoming SDGs’ [sustainable development goals] water-related targets. Such indicators will need to rely on national data, must consider the variation in data availability, and can be complemented with new cost-effective ways for data collection.

Remote sensing measurements, …