Natural Resource Economics Commons^™

The Importance Of Scaling For Detecting Community Patterns: Success And Failure In Assemblages Of Introduced Species, Craig R. Allen, David G. Angeler, Michael P. Moulton, Crawford S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Community saturation can help to explain why biological invasions fail. However, previous research has documented inconsistent relationships between failed invasions (i.e., an invasive species colonizes but goes extinct) and the number of species present in the invaded community. We use data from bird communities of the Hawaiian island of Oahu, which supports a community of 38 successfully established introduced birds and where 37 species were introduced but went extinct (failed invasions). We develop a modified approach to evaluate the effects of community saturation on invasion failure. Our method accounts (1) for the number of species present (NSP) when the species …

Effects Of Alternative Framing On The Publics Perceived Importance Of Environmental Conservation, Amanda E. Sorensen, Daniel Clark, Rebecca C. Jordan

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Effective communication of science to the general public is important for numerous reasons, including support for policy, funding, informed public decision making, among others. Prior research has found that scientists participating in public policy and public communication must frame their communication efforts in order to connect with audiences. A frame is the mechanism that individuals use to understand and interpret the world around them. Framing can encourage specific interpretations and reference points for a particular issue or event; especially when meaning is negotiated between the media and public audiences. In this study, we looked at the effect of framing within …

Five-Year Growth Report: From Inception To Global Influence 2010 - 2015, Robert B. Daugherty Water For Food Institute

Daugherty Water for Food Global Institute: Administrative Materials

While we are proud of our accomplishments in building an institutional framework, we are even more proud of our institute’s initial work to build an impact-driven program. This work is indeed the central focus of this report. Through the leadership of our new directors for research and policy, we have begun to build a vigorous research and policy development program that includes engagement with both local and global stakeholders. We have also developed a strong set of collaborations with national and international partners, striving to achieve a balance between work in Nebraska and globally, including in India, Brazil, China and …

The Effects Of Harvest Regulations On Behaviors Of Duck Hunters, Matthew T. Haugen, Larkin A. Powell, Mark P. Vrtiska, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Uncertainty exists as to how duck harvest regulations influence waterfowl hunter behavior. We used the U.S. Fish and Wildlife Service’s Parts Collection Survey to examine how harvest regulations affected behaviors of Central Flyway duck hunters. We stratified hunters into ranked groups based on seasonal harvest and identified three periods (1975–1984, 1988–1993, 2002–2011) that represented different harvest regulations (moderate, restrictive, and liberal, respectively; season length and daily bag limits smallest in restrictive seasons and largest in liberal seasons). We examined variability of seven measures of duck hunter behaviors across the periods: days harvesting ducks, daily harvest, hunter mobility, mallard (Anas platyrhynchos …

Masked Expression Of Life- History Traits In A Highly Variable Environment, Jason A. Deboer, Joseph J. Fontaine, Christopher J. Chizinski, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Differing life-history strategies may act as a constraint on reproductive expression that ultimately limits the ability of individual species to respond to changes in the magnitude or frequency of environmental variation, and potentially underlies the variation oft en inherent in phenotypic and evolved responses to anthropogenic change. Alternatively, if there are environmental cues that predict reproductive potential, differential expression of life-history strategies may represent differences in the adaptive capacity to optimize current reproductive value given variation in environmental conditions. We compared several aspects of walleye Sander vitreus spawning ecology at two reservoirs that diff er in environmental variability (i.e., annual …

Reservoir Area Of Influence And Implications For Fisheries Management, Dustin R. Martin, Christopher J. Chizinski, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Understanding the spatial area that a reservoir draws anglers from, defined as the reservoir’s area of influence, and the potential overlap of that area of influence between reservoirs is important for fishery managers. Our objective was to define the area of influence for reservoirs of the Salt Valley regional fishery in southeastern Nebraska using kernel density estimation. We used angler survey data obtained from in-person interviews at 17 reservoirs during 2009–2012. The area of influence, defined by the 95% kernel density, for reservoirs within the Salt Valley regional fishery varied, indicating that anglers use reservoirs differently across the regional fishery. …

Reservoir Rehabilitations: Seeking The Fountain Of Youth, Mark A. Pegg, Kevin L. Pope, Larkin A. Powell, Kelly C. Turek, Jonathan J. Spurgeon, Nathaniel T. Stewart, Nick P. Hogberg, Mark T. Porath

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aging of reservoirs alters the functions, and associated services, of these systems through time. The goal of habitat rehabilitation is often to alter the trajectory of the aging process such that the duration of the desired state is prolonged. There are two important characteristics in alteration of the trajectory—the amplitude relative to current state and the subsequent rate of change, or aging—that ultimately determine the duration of extension for the desired state. Rehabilitation processes largely fall into three main categories: fish community manipulation, water quality manipulation, and physical habitat manipulation. We can slow aging of reservoirs through carefully implemented management …

The Global Status Of Freshwater Fish Age Validation Studies And A Prioritization Framework For Further Research, Jonathan J. Spurgeon, Martin J. Hamel, Kevin L. Pope, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Age information derived from calcified structures is commonly used to estimate recruitment, growth, and mortality for fish populations. Validation of daily or annual marks on age structures is often assumed, presumably due to a lack of general knowledge concerning the status of age validation studies. Therefore, the current status of freshwater fish age validation studies was summarized to show where additional effort is needed, and increase the accessibility of validation studies to researchers. In total, 1351 original peer-reviewed articles were reviewed from freshwater systems that studied age in fish. Periodicity and age validation studies were found for 88 freshwater species …

Experimental Evaluation Of Rainbow Trout Oncorhynchus Mykiss Predation On Longnose Dace Rhinichthys Cataractae, Kelly C. Turek, Mark A. Pegg, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Laboratory and in-stream enclosure experiments were used to determine whether rainbow trout Oncorhynchus mykiss influence survival of longnose dace Rhinichthys cataractae. In the laboratory, adult rainbow trout preyed on longnose dace in 42% of trials and juvenile rainbow trout did not prey on longnose dace during the first 6 h after rainbow trout introduction. Survival of longnose dace did not differ in the presence of adult rainbow trout previously exposed to active prey and those not previously exposed to active prey (x²₁ = 0.28, P = 0.60). In field enclosures, the number of longnose dace decreased at …

Barriers And Bridges To The Integration Of Social–Ecological Resilience And Law, Olivia Odom Green, Ahjond S. Garmestani, Craig R. Allen, Lance H. Gunderson, J.B. Ruhl, Craig A. Arnold, Nicholas A.J. Graham, Barbara Cosens, David G. Angeler, Brian C. Chaffin, C.S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

There is a fundamental difference between the ways in which ecologists and lawyers view uncertainty: in the study of ecology, uncertainty provides a catalyst for exploration, whereas uncertainty is antithetical to the rule of law. This issue is particularly troubling in environmental management, where the tensions between law and ecology become apparent. Rather than acknowledge uncertainties in management actions, legal frameworks often force a false sense of certainty in linking cause and effect. While adaptive management has been developed to deal with uncertainty, laws and legal wrangling can be obstacles to implementation. In this article, we recommend resilience-based governance – …

Quantifying The Adaptive Cycle, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term …

Across-Ecoregion Analysis Suggests A Hierarchy Of Ecological Filters That Regulate Recruitment Of A Globally Invasive Fish, Przemek G. Bajer, Timothy K. Cross, Joseph D. Lechelt, Christopher J. Chizinski, Michael J. Weber, Peter W. Sorensen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aim -- Even successful invaders are abundant only in a fraction of locales they inhabit. One of the main challenges in invasion ecology is explaining processes that drive these patterns. We investigated recruitment of a globally invasive fish, common carp (Cyprinus carpio), across three ecoregions to determine the role of environmental characteristics, predatory communities and propagule pressure on the invasion process at coarse and fine spatial scales.

Location -- Lakes across Northern Forest, Temperate Forest and Great Plains ecoregions of North America.

Methods -- We used data from 567 lakes to model presence or absence of carp recruitment …

Estimation Of Daily Air Temperature Based On Modis Land Surface Temperature Products Over The Corn Belt In The Us, Linglin Zeng, Brian D. Wardlow, Tsegaye Tadesse, Jie Shan, Michael Hayes, Deren Li, Daxiang Xiang

Center for Advanced Land Management Information Technologies: Publications

Air temperature (Ta) is a key input in a wide range of agroclimatic applications. Moderate Resolution Imaging Spectroradiometer (MODIS) Ts (Land Surface Temperature (LST)) products are widely used to estimate daily Ta. However, only daytime LST (Ts-day) or nighttime LST (Ts-night) data have been used to estimate Tmax/Tmin (daily maximum or minimum air temperature), respectively. The relationship between Tmax and Ts-night, and the one between Tmin and Ts-day has not been studied. In this study, both the ability of Ts-night data to estimate Tmax and the ability of Ts-day data to estimate Tmin were tested and studied in the Corn …

Reforestation, Renewal, And The Cost Of Coal: Opposing A Manichean Worldview In Central Appalachia, Elizabeth R. Hansen

Pomona Senior Theses

Surface coal mining is a major form of land change and environmental degradation in Central Appalachia. Traditional mine reclamation iresults in unmanaged, unproductive grasslands that fail to mitigate many of the environmental costs of coal mining and are of minimal use to communities. Forestry reclamation is an alternative reclamation tactic that has the potential to address both environmental and socioeconomic concerns in Central Appalachia. A case study of Laurel Fork Mine in Eastern Kentucky is included.

U.S. Drought Monitor, December 30, 2014, Brad Rippey

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 30, 2014 (12/30/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, December 16, 2014, David Miskus

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 16, 2014 (12/16/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, December 9, 2014, Anthony Artusa

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 9, 2014 (12/9/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, December 2, 2014, Anthony Artusa

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for December 2, 2014 (12/2/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …

U.S. Drought Monitor, November 25, 2014, Eric Luebehusen

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for November 25, 2014 (11/25/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, November 18, 2014, Eric Luebehusen

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for November 18, 2014 (11/18/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, November 11, 2014, Matthew Rosencrans

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for November 11, 2014 (11/11/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, November 4, 2014, Matthew Rosencrans

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for November 4, 2014 (11/4/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, October 28, 2014, Brian Fuchs

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for October 28, 2014 (10/28/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, October 21, 2014, Michael J. Brewer

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for October 21, 2014 (10/21/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, October 14, 2014, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for October 14, 2014 (10/14/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, October 7, 2014, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for October 7, 2014 (10/7/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.

U.S. Drought Monitor, September 30, 2014, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of the United States for September 30, 2014 (9/30/14) plus: United States crop areas experiencing drought (map), an approximate percentage of crop located in drought by state (bar graph), and the percentage of crop area located in drought during the past 52 weeks (line graph) for corn, soybeans, hay, cattle, and winter wheat.

U.S. Drought Monitor, September 23, 2014, Richard R. Heim Jr.

United States Agricultural Commodities in Drought Archive

Drought map of the United States for September 23, 2014 (9/23/14) plus: United States crop areas experiencing drought (map), an approximate percentage of crop located in drought by state (bar graph), and the percentage of crop area located in drought during the past 52 weeks (line graph) for corn, soybeans, hay, cattle, and winter wheat.

U.S. Drought Monitor, September 16, 2014, Michael J. Brewer

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for September 16, 2014 (9/16/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.