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Using The Internet To Understand Angler Behavior In The Information Age, Dustin R. Martin, Brenda M. Pracheil, Jason A. Deboer, Gene R. Wilde, Kevin L. Pope Oct 2012

Using The Internet To Understand Angler Behavior In The Information Age, Dustin R. Martin, Brenda M. Pracheil, Jason A. Deboer, Gene R. Wilde, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Declining participation in recreational angling is of great concern to fishery managers because fishing license sales are an important revenue source for protection of aquatic resources. This decline is frequently attributed, in part, to increased societal reliance on electronics. Internet use by anglers is increasing and fishery managers may use the Internet as a unique means to increase angler participation. We examined Internet search behavior using Google Insights for Search, a free online tool that summarizes Google searches from 2004 to 2011 to determine (1) trends in Internet search volume for general fishing-related terms and (2) the relative usefulness of …


Habitat Selection By Adult Walleye During Spawning Season In Irrigation Reservoirs: A Patch Occupancy Modeling Approach, Dustin R. Martin, Larkin A. Powell, Kevin L. Pope Jan 2012

Habitat Selection By Adult Walleye During Spawning Season In Irrigation Reservoirs: A Patch Occupancy Modeling Approach, Dustin R. Martin, Larkin A. Powell, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recruitment of walleye (Sander vitreus Mitchill) is limited in irrigation reservoirs of the Republican River basin in southwestern Nebraska. The causal mechanism for this limited recruitment is unknown, but may be related to a lack of suitable spawning habitat. Patch occupancy models were developed to describe variation in detection probability and habitat selection during spawning season using shoreline electrofishing data. Detection of adult walleye was negatively affected by water temperature, silt substrate, and woody cover. Adult walleye selected sites with cooler water temperatures and greater fetch at Enders Reservoir, and large rock substrate and no cover at Hugh Butler …


Predictions And Retrodictions Of The Hierarchical Representation Of Habitat In Heterogeneous Environments, Jurek Kolasa, Craig R. Allen, Jan Sendzimir, Craig A. Stow Jan 2012

Predictions And Retrodictions Of The Hierarchical Representation Of Habitat In Heterogeneous Environments, Jurek Kolasa, Craig R. Allen, Jan Sendzimir, Craig A. Stow

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Interaction between habitat and species is central in ecology. Habitat structure may be conceived as being hierarchical, where larger, more diverse, portions or categories contain smaller, more homogeneous portions. When this conceptualization is combined with the observation that species have different abilities to relate to portions of the habitat that differ in their characteristics, a number of known patterns can be derived and new patterns hypothesized. We propose a quantitative form of this habitat–species relationship by considering species abundance to be a function of habitat specialization, habitat fragmentation, amount of habitat, and adult body mass. The model reproduces and explains …


The Feasibility Of Switchgrass For Biofuel Production, Rob Mitchell, Kenneth P. Vogel, Daniel R. Uden Jan 2012

The Feasibility Of Switchgrass For Biofuel Production, Rob Mitchell, Kenneth P. Vogel, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Switchgrass research has been conducted cooperatively by the US Department of Agriculture and the University of Nebraska since the mid-1930s, with a primary focus on bioenergy since 1990 at several institutions. Progress has been made in switchgrass breeding and genetics, molecular genetics, establishment, fertility management, production economics, production energetics, harvest and storage management, ecosystem services and ethanol yield. A complete field-validated biomass production system has been developed for the Midwest and Central Plains. Even with favorable economic and sustainability results from field trials, switchgrass for bioenergy has not been adopted on a large scale. Lack of adoption is likely due …


Variation In Native Micro-Predator Abundance Explains Recruitment Of A Mobile Invasive Fish, The Common Carp, In A Naturally Unstable Environment, Przemyslaw G. Bajer, Christopher J. Chizinski, Justin J. Silbernagel, Peter W. Sorensen Jan 2012

Variation In Native Micro-Predator Abundance Explains Recruitment Of A Mobile Invasive Fish, The Common Carp, In A Naturally Unstable Environment, Przemyslaw G. Bajer, Christopher J. Chizinski, Justin J. Silbernagel, Peter W. Sorensen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Why certain species of fish become invasive is poorly understood and a key obstacle to restoring many of the world’s ecosystems. In this study we tested whether variation in biotic resistance exerted by native predators might explain the reproductive success of the common carp, a large and fecund invasive species that typically spawns in outlying and unstable shallow habitat. An initial three-year study of the relative abundance of youngof- year (YOY) carp in interconnected lakes in the Upper Mississippi River Basin discovered that YOY carp are only found in shallow waters that experience winter hypoxia (winterkill) and have low densities …


Nest Predation, Food, And Female Age Explain Seasonal Declines In Clutch Size, Karie L. Decker, Courtney J. Conway, Joseph J. Fontaine Jan 2012

Nest Predation, Food, And Female Age Explain Seasonal Declines In Clutch Size, Karie L. Decker, Courtney J. Conway, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The selection pressures responsible for intra- and interspecific variation in avian clutch size have been debated for over half a century. Seasonal declines in clutch size represent one of the most robust patterns in avian systems, yet despite extensive research on the subject, the mechanisms underlying this pattern remain largely unknown. We tested a combination of experimental and observational predictions to evaluate ten hypotheses, representing both evolutionary and proximate mechanisms proposed to explain seasonal declines in avian clutch size. In line with long held life-history theory, we found strong support for both an evolved and proximate response to food availability …


Land Use, Landscapes, And Biological Invasions, Karie L. Decker, Craig R. Allen, Leonardo Acosta, Michelle L. Hellman, Christopher F. Jorgensen, Ryan J. Stutzman, Kody M. Unstad, Amy Williams, Matthew Yans Jan 2012

Land Use, Landscapes, And Biological Invasions, Karie L. Decker, Craig R. Allen, Leonardo Acosta, Michelle L. Hellman, Christopher F. Jorgensen, Ryan J. Stutzman, Kody M. Unstad, Amy Williams, Matthew Yans

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The negative effect of invasive species on native species, communities, and ecosystems is widely recognized, and the economic effects in the United States are estimated to be billions of dollars annually. Studies often examine traits of nonnative species or examine what makes a particular habitat invasible. To better understand the factors governing invasions, we used the flora of Nebraska to characterize and compare native and nonnative plant occurrences throughout the state. In addition, we assessed four critical landscape predictors of nonnative plant richness: human population size and three land cover attributes that included percentage of grassland, percentage of agriculture, and …


Population Estimate Of Chinese Mystery Snail (Bellamya Chinensis) In A Nebraska Reservoir, Noelle M. Chaine, Craig R. Allen, Kent A. Fricke, Danielle M. Haak, Michelle L. Hellman, Robert A. Kill, Kristine T. Nemec, Kevin L. Pope, Nicholas A. Smeenk, Bruce J. Stephen, Daniel R. Uden, Kody M. Unstad, Ashley E. Vanderham Jan 2012

Population Estimate Of Chinese Mystery Snail (Bellamya Chinensis) In A Nebraska Reservoir, Noelle M. Chaine, Craig R. Allen, Kent A. Fricke, Danielle M. Haak, Michelle L. Hellman, Robert A. Kill, Kristine T. Nemec, Kevin L. Pope, Nicholas A. Smeenk, Bruce J. Stephen, Daniel R. Uden, Kody M. Unstad, Ashley E. Vanderham

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail (Bellamya chinensis) is an aquatic invasive species in North America. Little is known regarding this species’ impacts on freshwater ecosystems. It is believed that population densities can be high, yet no population estimates have been reported. We utilized a mark-recapture approach to generate a population estimate for Chinese mystery snail in Wild Plum Lake, a 6.47-ha reservoir in southeast Nebraska. We calculated, using bias-adjusted Lincoln-Petersen estimation, that there were approximately 664 adult snails within a 127 m2 transect (5.2 snails/m2). If this density was consistent throughout the littoral zone (depth) of …