Aquaculture and Fisheries Commons^™

Potential Population And Assemblage Influences Of Non-Native Trout On Native Nongame Fish In Nebraska Headwater Streams, Kelly C. Turek, Mark A. Pegg, Kevin L. Pope, Steve Schainost

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Non-native trout are currently stocked to support recreational fisheries in headwater streams throughout Nebraska. The influence of non-native trout introductions on native fish populations and their role in structuring fish assemblages in these systems is unknown. The objectives of this study were to determine (i) if the size structure or relative abundance of native fish differs in the presence and absence of non-native trout, (ii) if native fish-assemblage structure differs in the presence and absence of non-native trout and (iii) if native fish-assemblage structure differs across a gradient in abundances of non-native trout. Longnose dace Rhinichthys cataractae were larger in …

Letter Resisting Resilience Theory: Aresponse To Connelland Ghedini, Shana M. Sundstrom, Craig R. Allen, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

ConnellandGhedini [1] arguethatecolo- gistsareprimarily [1TD$DIF]concernedwithcommu- nitychangeandtendtoignoreprocesses liketrophiccompensationthatcontribute to communityorsystem-levelstability. Resilience,theyclaim,isthestudyof change,andresearchersshouldspend moretimestudyingstabilizingprocesses to betterpredictthetypesofchanges documentedbyecologistswhostudyresil- ience [2,3]. Thebulkoftheirpaper addressesresilienceandrelatedconcepts to contextualizeresistancetochange,but theirargumentsarediminishedbecause theauthorsfailtoexplicitlyplacetheirwork withintherangeofresilienceconceptsthat haveproliferatedacrossacademicdisci- plines.Moreimportantly,thepaperfurthers confusionregardingcoreecologicalresil- ienceconcepts.Withinthedisciplineof ecology,resilienceconceptshavebeen developedinafundamentallycohesive way [4]. Understandingtheresilienceof complexsystemsofhumansandnature duringthistimeofrapidglobalchangeis importantandthemisuseorcasualuseof conceptswithspecific meaningismore thansimplyatrivialpointofcontention;it potentiallyobscuresprocessesandprop- ertiesthathavedirectrelevancetohuman- ity'sinteractionwiththeenvironment.

Influence Of Anglers’ Specializations On Catch, Harvest, And Bycatch Of Targeted Taxa, Kevin L. Pope, Christopher J. Chizinski, Christopher L. Wiley, Dustin R. Martin

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Fishery managers often use catch per unit effort (CPUE) of a given taxon derived from a group of anglers,those that sought said taxon, to evaluate fishery objectives because managers assume CPUE for this group of anglers is most sensitive to changes in fish taxon density. Further, likelihood of harvest may differ for sought and non-sought taxa if taxon sought is a defining characteristic of anglers’ attitude toward harvest.We predicted that taxon-specific catch across parties and reservoirs would be influenced by targeted taxon after controlling for number of anglers in a party and time spent fishing (combine to quantify fishing effort …

Hypoxia Affects Performance Traits And Body Composition Of Juvenile Hybrid Striped Bass (Morone Chrysops X M. Saxatilis), Bartholomew W. Green, Steven D. Rawles, Sidney A. Fuller, Benjamin H. Beck, Matthew E. Mcentire

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Performance traits and body composition of juvenile hybrid striped bass (Morone chrysops x M. saxatilis) in response to hypoxia were evaluated in replicate tanks maintained at constant dissolved oxygen concentrations that averaged 23.0 ± 2.3%, 39.7 ± 3.0%, and 105.5 ± 9.5% dissolved oxygen saturation. Fish were fed a commercially formulated feed daily to apparent satiation. Total feed intake and fish growth and yield increased linearly in response to increased dissolved oxygen concentration. Nutrient utilization was reduced significantly only at the greatest level of hypoxia. With the exception of whole-body protein content, whole body compositional indices and nutrient …

Adaptive Management For Soil Ecosystem Services, Hannah E. Birge, Rebecca A. Bevans, Craig R. Allen, David G. Angeler, Sara G. Baer, Diana H. Wall Colorado State University

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

No abstract provided.

Transformative Environmental Governance, Brian C. Chaffin, Ahjond Garmestani, Lance Gunderson, Melinda Harm Benson, David G. Angeler, Craig Anthony (Tony) Arnold, Barbara Cosens, Robin Kundis Craig, J.B. B. Ruhl, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Transformative governance is an approach to environmental governance that has the capacity to respond to, manage, and trigger regime shifts in coupled social-ecological systems (SESs) at multiple scales. The goal of transformative governance is to actively shift degraded SESs to alternative, more desirable, or more functional regimes by altering the structures and processes that define the system. Transformative governance is rooted in ecological theories to explain cross-scale dynamics in complex systems, as well as social theories of change, innovation, and technological transformation. Similar to adaptive governance, transformative governance involves a broad set of governance components, but requires additional capacity to …

Using Standardized Fishery Data To Inform Rehabilitation Efforts, Jonathan J. Spurgeon, Nathaniel T. Stewart, Mark A. Pegg, Kevin L. Pope, Mark T. Porath

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Lakes and reservoirs progress through an aging process often accelerated by human activities, resulting in degradation or loss of ecosystem services. Resource managers thus attempt to slow or reverse the negative effects of aging using a myriad of rehabilitation strategies. Sustained monitoring programs to assess the efficacy of rehabilitation strategies are often limited; however, long-term standardized fishery surveys may be a valuable data source from which to begin evaluation.We present 3 case studies using standardized fishery survey data to assess rehabilitation efforts stemming from the Nebraska Aquatic Habitat Plan, a large-scale program with the mission to rehabilitate waterbodies within the …

Deathcore, Creativity, And Scientific Thinking, David G. Angeler, Shana M. Sundstrom, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Background Major scientific breakthroughs are generally the result of materializing creative ideas, the result of an inductive process that sometimes spontaneously and unexpectedly generates a link between thoughts and/or objects that did not exist before. Creativity is the cornerstone of scientific thinking, but scientists in academia are judged by metrics of quantification that often leave little room for creative thinking. In many scientific fields, reductionist approaches are rewarded and new ideas viewed skeptically. As a result, scientific inquiry is often confined to narrow but safe disciplinary ivory towers, effectively preventing profoundly creative explorations that could yield unexpected benefits.

This paper …

Fishing For Ecosystem Services, Kevin L. Pope, Mark A. Pegg, Nicholas W. Cole, Stephen F. Siddons, Alexis D. Fedele, Brian S. Harmon, Ryan L. Ruskamp, Dylan R. Turner, Caleb C. Uerling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Ecosystems are commonly exploited and manipulated to maximize certain human benefits. Such changes can degrade systems, leading to cascading negative effects that may be initially undetected, yet ultimately result in a reduction, or complete loss, of certain valuable ecosystem services. Ecosystembased management is intended to maintain ecosystem quality and minimize the risk of irreversible change to natural assemblages of species and to ecosystem processes while obtaining and maintaining long-term socioeconomic benefits. We discuss policy decisions in fishery management related to commonly manipulated environments with a focus on influences to ecosystem services. By focusing on broader scales, managing for ecosystem services, …

Genetic Correlates Of Individual Differences In Sleep Behavior Of Free-Living Great Tits (Parus Major), Erica F. Stuber, Christine Baumgartner, Niels J. Dingemanse, Bart Kempenaers, Jakob C. Mueller

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Within populations, free-living birds display considerable variation in observable sleep behaviors, reflecting dynamic interactions between individuals and their environment. Genes are expected to contribute to repeatable between-individual differences in sleep behaviors, which may be associated with individual fitness. We identified and genotyped polymorphisms in nine candidate genes for sleep, and measured five repeatable sleep behaviors in free-living great tits (Parus major), partly replicating a previous study in blue tits (Cyanistes caeruleus). Microsatellites in the CLOCK and NPAS2 clock genes exhibited an association with sleep duration relative to night length, and morning latency to exit the nest …

Body Size Distributions Signal A Regime Shift In A Lake Ecosystem, Trisha L. Spanbauer, Craig R. Allen, David G. Angeler, Tarsha Eason, Sherilyn C. Fritz, Ahjond S. Garmestani, Kirsty L. Nash, Jeffery R. Stone, Craig A. Stow, Shana M. Sundstrom

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Communities of organisms, from mammals to microorganisms, have discontinuous distributions of body size. This pattern of size structuring is a conservative trait of community organization and is a product of processes that occur at multiple spatial and temporal scales. In this study, we assessed whether body size patterns serve as an indicator of a threshold between alternative regimes. Over the past 7000 years, the biological communities of Foy Lake (Montana, USA) have undergone a major regime shift owing to climate change. We used a palaeoecological record of diatom communities to estimate diatom sizes, and then analysed the discontinuous distribution of …

Factors Influencing Recruitment Of Walleye And White Bass To Three Distinct Early Ontogenetic Stages, Jason A. Deboer, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Determining the factors that influence recruitment to sequential ontogenetic stages is critical for understanding recruitment dynamics of fish and for effective management of sportfish, particularly in dynamic and unpredictable environments. We sampled walleye (Sander vitreus) and white bass (Morone chrysops) at 3 ontogenetic stages (age 0 during spring: ‘age-0 larval’; age 0 during autumn: ‘age-0 juvenile’; and age 1 during autumn: ‘age-1 juvenile’) from 3 reservoirs. We developed multiple linear regression models to describe factors influencing age-0 larval, age-0 juvenile and age-1 juvenile walleye and white bass abundance indices. Our models explained 40–80% (68 ± 9%; …

Adaptive Management For Ecosystem Services, Hannah E. Birgé, Craig R. Allen, Ahjond S. Garmestani, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Management of natural resources for the production of ecosystem services, which are vital for human well-being, is necessary even when there is uncertainty regarding system response to management action. This uncertainty is the result of incomplete controllability, complex internal feedbacks, and nonlinearity that often interferes with desired management outcomes, and insufficient understanding of nature and people. Adaptive management was developed to reduce such uncertainty. We present a framework for the application of adaptive management for ecosystem services that explicitly accounts for cross-scale tradeoffs in the production of ecosystem services. Our framework focuses on identifying key spatiotemporal scales (plot, patch, ecosystem, …

Landscape Context Influences Nest Survival In A Midwest Grassland, Victoria L. Simonsen, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Although the management and restoration of habitat is the key method to conserve species of interest, local habitat management often fails to elicit desired responses in populations. Landscape features beyond the local habitat scale affect the population dynamics of ring-necked pheasants (Phasianus colchicus), but the mechanism behind this response is unknown. One possibility is that nest survival, which is primarily reduced by nest predation, is regulating pheasant responses to the landscape. We investigated the extent to which land use affected nest survival by studying 202 artificial nests on 12 Conservation Reserve Program (CRP) fields in Nebraska, USA with …

Management Applications Of Discontinuity Theory, David G. Angeler, Craig R. Allen, Chris Barichievy, Tarsha Eason, Ahjond S. Garmestani, Nicholas A.J. Graham, Dean Granholm, Lance H. Gunderson, Melinda Knutson, Kristy L. Nash, R. John Nelson, Magnus Nystrom, Trisha L. Spanbauer, Craig A. Stow, Shana M. Sundstrom

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

1. Human impacts on the environment are multifaceted and can occur across distinct spatiotemporal scales. Ecological responses to environmental change are therefore difficult to predict, and entail large degrees of uncertainty. Such uncertainty requires robust tools for management to sustain ecosystem goods and services and maintain resilient ecosystems.

2. We propose an approach based on discontinuity theory that accounts for patterns and processes at distinct spatial and temporal scales, an inherent property of ecological systems. Discontinuity theory has not been applied in natural resource management and could therefore improve ecosystem management because it explicitly accounts for ecological complexity.

3. Synthesis …

Quantifying Spatial Resilience, Craig R. Allen, David G. Angeler, Graeme S. Cumming, Carl Folke, Dirac L. Twidwell, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

1. Anthropogenic stressors affect the ecosystems upon which humanity relies. In some cases when resilience is exceeded, relatively small linear changes in stressors can cause relatively abrupt and nonlinear changes in ecosystems.

2. Ecological regime shifts occur when resilience is exceeded and ecosystems enter a new local equilibrium that differs in its structure and function from the previous state. Ecological resilience, the amount of disturbance that a system can withstand before it shifts into an alternative stability domain, is an important framework for understanding and managing ecological systems subject to collapse and reorganization.

3. Recently, interest in the influence of …

Biological Invasions, Ecological Resilience And Adaptive Governance, Brian C. Chaffin, Ahjond S. Garmestani, David G. Angeler, Dustin L. Herrmann, Craig A. Stow, Magnus Nystrom, Jan Sendzimir, Matthew E. Hopton, Jurek Kolasa, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

In a world of increasing interconnections in global trade as well as rapid change in climate and land cover, the accelerating introduction and spread of invasive species is a critical concern due to associated negative social and ecological impacts, both real and perceived. Much of the societal response to invasive species to date has been associated with negative economic consequences of invasions. This response has shaped a war-like approach to addressing invasions, one with an agenda of eradications and intense ecological restoration efforts towards prior or more desirable ecological regimes. This trajectory often ignores the concept of ecological resilience and …

Avoiding Decline: Fostering Resilience And Sustainability In Midsize Cities, Craig R. Allen, Hannah E. Birge, Shannon L. Bartelt-Hunt, Rebecca Bevans, Jessica L. Burnett, Barbara A. Cosens, Ximing Cai, Ahjond S. Garmestani, Igor Linkov, Elizabeth A. Scott, Mark D. Solomon, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Eighty-five percent of United States citizens live in urban areas. However, research surrounding the resilience and sustainability of complex urban systems focuses largely on coastal megacities (>1 million people). Midsize cities differ from their larger counterparts due to tight urban-rural feedbacks with their immediate natural environments that result from heavy reliance and close management of local ecosystem services. They also may be less path-dependent than larger cities due to shorter average connection length among system components, contributing to higher responsiveness among social, infrastructural, and ecological feedbacks. These distinct midsize city features call for a framework that organizes information and …

Early Life History Of Three Pelagic-Spawning Minnows Macrhybopsis Spp. In The Lower Missouri River, T. A. Starks, M. L. Miller, J. M. Long

United States Army Corps of Engineers, Omaha District

Life-history characteristics of age-0 sturgeon chub Macrhybopsis gelida, shoal chub Macrhybopsis hyostoma and sicklefin chub Macrhybopsis meeki were compared using several methods. All Macrhybopsis species consumed mostly midge pupae, but M. meeki had the most general diet (Levins’ index, B=0⋅22) compared with M. hyostoma (B=0⋅02) and M. gelida (B=0⋅09). Morisita’s diet overlap index among species pairs ranged from 0⋅62 to 0⋅97 and was highest between M. hyostoma and M. gelida. Daily ages estimated from lapilli otoliths for each species ranged from 15 to 43 days for M. gelida, 19 to 44 for …

Fishing Diseased Abalone To Promote Yield And Conservation, Tal Ben-Horin, Kevin D. Lafferty, Gorka Bidegain, Hunter S. Lenihan

United States Geological Survey: Staff Publications

Past theoretical models suggest fishing disease-impacted stocks can reduce parasite transmission, but this is a good management strategy only when the exploitation required to reduce transmission does not overfish the stock. We applied this concept to a red abalone fishery so impacted by an infectious disease (withering syndrome) that stock densities plummeted and managers closed the fishery. In addition to the non-selective fishing strategy considered by past disease- fishing models, we modelled targeting (culling) infected individuals,which is plausible in red abalone because modern diagnostic tools can determine infection without harming landed abalone and the diagnostic cost is minor relative to …

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

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 …

The Status Of Fishes In The Missouri River, Nebraska: Selected Ancient Fishes, Kirk D. Steffensen

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Several ancient fish species have inhabited the Missouri River and its tributaries for thousands of years prior to major mainstem modifications and fragmentation. However post-anthropogenic modifications, populations of these ancient fish species have been highly diminished. Therefore, the objective of this study was to use historic and current ichthyological records to determine the past and present status for Chestnut Lamprey Ichthyomyzon castaneus, Silver Lamprey Ichthyomyzon unicuspis, Bowfin Amia calva, American Eel Anguilla rostrata, and Burbot Lota lota. Currently, these species are rarely captured and perhaps extirpated from Nebraska waters.

Population Dynamics And Movement Of Channel Catfish In The Red River Of The North, Stephen F. Siddons

School of Natural Resources: Dissertations, Theses, and Student Research

Channel Catfish are widely distributed across North America and highly valued as a sport fish and for food. While most Channel Catfish fisheries are managed under liberal harvest regulations, the Red River of the North (Red River) in Manitoba, Canada is managed with restrictive harvest regulations to promote a trophy fishery. Two barriers (dams) are present on the main stem of the Red River and may fragment the population to some degree. My objectives were to: 1) analyze population dynamics of the trophy Channel Catfish population on the lower Red River, 2) compare population characteristics of Channel Catfish in selected …

Spreading Holiday Spirit And Northwestern Salamanders, Ambystoma Gracile (Baird 1859) (Caudata: Ambystomatidae), Across The Usa, Michael R. Rochford, Jeffrey M. Lemm, Kenneth Krysko, Louis A. Somma, Robert W. Hansen, Frank J. Mazzotti

Papers in Herpetology

Introduced species of amphibians and reptiles are of growing conservation concern (Bury and Luckenbach 1976; Krysko et al. 2011; Meshaka 2011). Unintentional introductions result largely from individuals escaping from enclosures or hitch-hiking in cargo or on vehicles, whereas intentional introductions occur primarily because a species is perceived to be of value to humans or from deliberately releasing sick or unwanted animals, including pets (Kraus 2009; Krysko et al. 2011). In Florida, most known introductions are directly related to the pet trade, but about 12% are related to the cargo pathway (Krysko et al. 2011). In this paper, we report the …

Blow-Up Of Positive Solutions To Wave Equations In High Space Dimensions, Mohammad A. Rammaha, Hiroyuki Takamura, Hiroshi Uesaka, Kyouhei Wakasa

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

This paper is concerned with the Cauchy problem for the semilinear wave equation:

utt - u = F(u) in Rn X [0;1);

where the space dimension n >2, F(u) = jujp or F(u) = up-1u with p>1. Here, the Cauchy data are non-zero and non-compactly supported. Our results on the blow-up of positive radial solutions (not necessarily radial in low dimensions n=2,3) generalize and extend the results of Takamura [19] for zero initial position and Takamura, Uesaka and Wakasa [21] for zero intitial velocity. The main technical difficulty in the paper lies in obtaining the lower bounds for for …

Genetic And Morphological Variation In Ecuadorian Astroblepid Catfishes, Katherine M. Lawry

School of Natural Resources: Dissertations, Theses, and Student Research

The Andean ichthyofauna remains a poorly understood component of Neotropical biodiversity, and stands in stark contrast to the lowland ichthyofauna in terms of number of species and range of distribution. The Climate Variability Hypothesis (CVH) predicts rapid turnover of species along elevational gradients in tropical climates, but it remains unclear whether stream fishes follow this pattern. Astroblepid catfishes represent a distinctive assemblage of species that inhabit high elevation streams throughout the Andes from Panama to Bolivia, and constitute the only native fish family present in the Ecuadorian highland region. In this research, population samples of Astroblepids collected throughout Ecuador’s Napo …

Ecology And Management Of Superabundant Fish Populations, Nathaniel T. Stewart

School of Natural Resources: Dissertations, Theses, and Student Research

Fish population biomasses can reach extreme levels; we term these populations superabundant fish populations. Superabundant fish populations may negatively affect aquatic communities and anglers, necessitating the effective management of the superabundant fish populations. However, there are gaps in our understanding of these populations. The gaps in our understanding hamper our ability to predict effects on valuable sportfisheries and to effectively manage superabundant fish populations. The overall goal of my thesis research is to provide further insight into the ecology of superabundant fish populations and to provide information that will aid in their effective management. First, we described a new method …

Bioenergetics And Habitat Suitability Models For The Chinese Mystery Snail (Bellamya Chinensis), Danielle M. Haak

School of Natural Resources: Dissertations, Theses, and Student Research

Relatively little is known about the invasive Chinese mystery snail (Bellamya chinensis). This research aims to elucidate some of the mystery surrounding this species. First, we place the species in context with other invasive freshwater snails of the USA and Canada, identifying current information gaps, categorizing shared characteristics among families and species, and comparing functional roles and ecological effects of freshwater snails. We conclude that more focus needs to be directed to regulating the aquarium, pet, and food trades if we are serious about preventing future invasions. Next, we develop a bioenergetics model for the species by quantifying …

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 …