Natural Resource Economics Commons^™

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 …

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 …

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 …

Accuracy Or Precision: Implications Of Sample Design And Methodology On Abundance Estimation, Lucas K. Kowalewski, Christopher J. Chizinski, Larkin A. Powell, Kevin L. Pope, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Sampling by spatially replicated counts (point-count) is an increasingly popular method of estimating population size of organisms. Challenges exist when sampling by point-count method, and it is often impractical to sample entire area of interest and impossible to detect every individual present. Ecologists encounter logistical limitations that force them to sample either few large-sample units or many small sample-units, introducing biases to sample counts. We generated a computer environment and simulated sampling scenarios to test the role of number of samples, sample unit area, number of organisms, and distribution of organisms in the estimation of population sizes using N-mixture …

Predictions Of Future Ephemeral Springtime Waterbird Stopover Habitat Availability Under Global Change, Daniel R. Uden, Craig R. Allen, Andrew A. Bishop, Roger Grosse, Christopher F. Jorgensen, Theodore G. Lagrange, Randy G. Stutheit, Mark P. Vrtiska

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In the present period of rapid, worldwide change in climate and landuse (i.e., global change), successful biodiversity conservation warrants proactive management responses, especially for long-distance migratory species. However, the development and implementation of management strategies can be impeded by high levels of uncertainty and low levels of control over potentially impactful future events and their effects. Scenario planning and modeling are useful tools for expanding perspectives and informing decisions under these conditions. We coupled scenario planning and statistical modeling to explain and predict playa wetland inundation (i.e., presence/absence of water) and ponded area (i.e., extent of water) in the Rainwater …

2015 Academic Program Review School Of Natural Resources University Of Nebraska–Lincoln

School of Natural Resources: Documents and Reviews

No abstract provided.

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

Daugherty Water for Food Global Institute: Literature

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 …

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 …

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 …

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 …