Aquaculture and Fisheries Commons^™

Age-0 Walleye Sander Vitreus Display Length-Dependent Diet Shift To Piscivory, Christopher S. Uphoff, Casey W. Schoenebeck, Keith D. Koupal, Kevin L. Pope, W. Wyatt Hoback

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The ontogenetic diet shift to piscivory can be energetically beneficial for fish growth and allows larger, more energetically profitable prey to be consumed. A shift to piscivory may be easier for longer individuals within a cohort due to larger gape size, and an early shift is likely advantageous, potentially leading to increased growth rates and survival. Such length-dependent ontogenetic diet shifts may explain the intracohort variability in length that is common for age-0 walleye (Sander vitreus). The objectives of this study were to describe seasonal intracohort variability in length, identify the timing of the shift to piscivory and …

Ecosystem Size Predicts Social-Ecological Dynamics, Mark A. Kaemingk, Christopher J. Chizinski, Craig R. Allen, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recreational fisheries are complex adaptive systems that are inherently difficult to manage because of heterogeneous user groups (consumptive vs. nonconsumptive) that use patchily distributed resources on the landscape (lakes, rivers, coastlines). There is a need to identify which system components can effectively predict and be used to manage nonlinear and cross-scale dynamics within these systems. We examine how ecosystem size or water body size can be used to explain complicated and elusive angler-resource dynamics in recreational fisheries. Water body size determined angler behavior among 48 Nebraska, U.S.A. water bodies during an 11- year study. Angler behavior was often unique and …

Effects Of Solids Removal On Water Quality And Channel Catfish Production In A Biofloc Technology Production System, Bartholomew W. Green, Kevin K. Schrader, Matthew Mcentire

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

Total suspended solids control was evaluated in a channel catfish (Ictalurus punctatus) biofloc technology production system. Settling chamber flow rates were 0.9 (LO) or 2.9 (HI) L/min to reduce total suspended solids to 300 mg/L; solids were not removed from control tanks. Channel catfish yields (7.6–8.7 kg/m3) were not affected significantly, but control fish were skewed toward smaller size classes. Control treatment channel catfish tolerated 1,410 mg/L total suspended solids without adverse effects. LO- and HI-treatment fillet geosmin concentrations were high enough to be designated as off-flavor. Water quality results suggested that nitrification was affected by solids removal.

Scaphanocephalus-Associated Dermatitis As The Basis For Black Spot Disease In Acanthuridae Of St. Kitts, West Indies, Michelle M. Dennis, Adrien Izquierdo, Anne Conan, Kelsey Johnson, Solenne Giardi, Paul Frye, Mark A. Freeman

Harold W. Manter Laboratory of Parasitology: Library Materials

Acanthurus spp. of St. Kitts and other Caribbean islands, including ocean surgeonfish A. bahianus, doctorfish A. chirurgus, and blue tang A. coeruleus, frequently show multifocal cutaneous pigmentation. Initial reports from the Leeward Antilles raised suspicion of a parasitic etiology. The aim of this study was to quantify the prevalence of the disease in St. Kitts’ Acanthuridae and describe its pathology and etiology. Visual surveys demonstrated consistently high adjusted mean prevalence at 3 shallow reefs in St. Kitts in 2017 (38.9%, 95% CI: 33.8−43.9) and 2018 (51.5%; 95% CI: 46.2−56.9). There were no differences in …

Novel Information On The Morphology, Phylogeny And Distribution Of Camallanid Mematodes From Marine And Freshwater Hosts In South Africa, Including The Description Of Camallanus Sodwanaensis N. Sp., Roman Svitin, Marliese Truter, Olena Kudlai, Nico J. Smit, Louis Du Preez

Harold W. Manter Laboratory of Parasitology: Library Materials

Four species of previously known nematodes from the family Camallanidae were found from different hosts in South Africa: Batrachocamallanus xenopodis from the frog Xenopus muelleri, Paracamallanus cyathopharynx, and Procamallanus pseudolaeviconchus from the catfish Clarias gariepinus and Spirocamallanus daleneae from the catfish Synodontis zambezensis. In the material collected from various marine fishes, several specimens of nematodes from the genus Camallanus clearly differed from all previously known species. Based on morphological differences these specimens are assigned to a new species, C. sodwanaensis. Molecular data of 18S and 28S rDNA and COI sequences are provided for the collected species …

Simulating Detection-Censored Movement Records For Home Range Analysis Planning, Lyndsie S. Wszola, Victoria L. Simonsen, Lucía Corral, Christopher J. Chizinski, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Home range estimation is an important analytical method in applied spatial ecology, yet best practices for addressing the effects of spatial variation in detection probability on home range estimates remain elusive. We introduce the R package “DiagnoseHR,” simulation tools for assessing how variation in detection probability arising from landscape, animal behavior, and methodological processes affects home range inference. We demonstrate the utility of simulation methods for home range analysis planning by comparing bias arising from three home range estimation methods under multiple detection scenarios. We simulated correlated random walks in three landscapes that varied in detection probability and constructed home …

Effect Of Stocking Rate On Growing Juvenile Sunshine Bass, Morone Chrysops × M. Saxatilis, In An Outdoor Biofloc Production System, Bartholomew W. Green, Steven D. Rawles, Carl D. Webster, Matthew E. Mcentire

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

The biofloc technology production system is a production intensifying management strategy used primarily for culturing tilapia and penaeid shrimp, both of which can consume the biofloc. Other fish can be grown in biofloc systems because the biofloc serves to maintain water quality, metabolizing the ammonia excreted by intensively fed fish. A dose-response study was conducted in an outdoor biofloc system to begin quantifying the stocking rate-production function for sunshine bass, Morone chrysops x M. saxatilis, advanced fingerlings. Sunshine bass (2.9 ± 0.2 g/fish) were stocked into tanks at 50 to 250 fish/m² in 50 fish/m² increments. After …

Can Lactate Dehydrogenase Be Used To Index Anaerobic Activity In Fishes?, Casey W. Schoenebeck, Erik Prenosil, Brianna Pallas, Aspen Abrams, Kimberly Carlson

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Anaerobic activities such as those associated with spawning, foraging for prey, and predator avoidance are difficult to quantify in wild fish. This study experimentally evaluated if the muscle enzyme lactate dehydrogenase (LDH) can be used to index recent anaerobic activity in fish by testing the hypothesis that muscle LDH activity will be greater in exercised fish than in rested fish. We used burst swimming motions in a swim tunnel to elicit anaerobic metabolism in a 5 day anaerobic exercise treatment (n = 30) and a rested control group (n = 30). On average the exercised fish produced significantly more LDH …

Ecological Neighborhoods As A Framework For Umbrella Species Selection, Erica F. Stuber, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Umbrella species are typically chosen because they are expected to confer protection for other species assumed to have similar ecological requirements. Despite its popularity and substantial history, the value of the umbrella species concept has come into question because umbrella species chosen using heuristic methods, such as body or home range size, are not acting as adequate proxies for the metrics of interest: species richness or population abundance in a multi-species community for which protection is sought. How species associate with habitat across ecological scales has important implications for understanding population size and species richness, and therefore may be a …

Potential Minimum Threshold For Pallid Sturgeon Relative Condition In The Lower Missouri River, Kirk D. Steffensen

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Pallid Sturgeon (Scaphirhynchus albus) condition has declined in the lower Missouri River but the cause and the effects of this decline remain uncertain. Adult Pallid Sturgeon are becoming reproductively ready less frequently and sub-adult Pallid Sturgeon are likely delaying sexual maturation. Even more concerning, Pallid Sturgeon capture rates have declined the past two years (i.e., 2016 and 2017), despite the ongoing Pallid Sturgeon stocking program. Several Pallid Sturgeon that have been captured are visually emaciated but a minimum condition threshold has not been described. Therefore, the aim of this study is to present a potential lethal condition level for …

Gulls, Martin S. Lowney, Scott F. Beckerman, Scott C. Barras, Thomas W. Seamans

Wildlife Damage Management Technical Series

Abundant gull (Figure 1) populations in North America have led to a variety of conflicts with people. Gulls cause damage at aquaculture facilities and other properties, and often collide with aircraft. Their use of structures on and near water results in excessive amounts of bird droppings on boats and docks. Their presence near outdoor dining establishments, swimming beaches, and recreational sites can lead to negative interactions with people. Large amounts of gull fecal material pollutes water and beaches resulting in drinking water contamination and swim bans. A combination of dispersal techniques, exclusion and limited lethal control may reduce damage to …

Synchrony — An Emergent Property Of Recreational Fisheries, Mark A. Kaemingk, Christopher J. Chizinski, Keith Hurley, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

1. Recreational fisheries are traditionally managed at local scales, but more effective management could be achieved using a cross-scale approach. To do this, we must first understand how local processes scale up to influence landscape patterns between anglers and resources. We highlight how population-based synchrony methods, used in conjunction with a complex-adaptive-systems framework, can reveal emergent spatial properties within social-ecological systems such as recreational fisheries.

2. Herein, we quantified the level of spatial synchrony in angler behaviour, defined the relationship between angler synchrony and distance among waterbodies, and highlighted social-ecological attributes contributing to these patterns. We leveraged a 111 waterbody-year …

Reducing Dietary Protein In Pond Production Of Hybrid Striped Bass (Morone Chrysops × M. Saxatilis): Effects On Fish Performance And Water Quality Dynamics, Steven Rawles, Bartholomew Green, Matthew Mcentire, T. Gibson Gaylord, Frederic T. Barrows

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

In previous work, we demonstrated that diets containing 40% digestible protein (DP) (45% crude protein) and 18% lipid supplemented with Met and Lys resulted in superior performance and nutrient retentions in hybrid striped bass (HSB) compared to less energy-dense diets when rearing HSB at temperatures similar to the summer growing period of the Southern U.S. The current work was aimed at vetting previous results in pond production of market-size HSB at commercial stocking densities to assess impacts on fish production indices and water quality parameters. Diets were formulated to contain digestible protein levels ranging from 41% to 35% DP and …

Nebraska Invasive Plants Field Guide, Nebraska Invasive Species Program

Nebraska Invasive Species Program

Invasive species are plants, animals or pathogens that are non-native to an ecosystem. They cause harm to the economy, environment or human health. They negatively affect native species and ecosystems and interfere with outdoor recreation opportunities. This guide identifies federal and state-listed noxious weeds. Federal noxious weeds are regulated by the U.S. Department of Agriculture; State noxious weeds are regulated by the Nebraska Department of Agriculture, Animal and Plant Health Protection, Noxious Weed Program. Aquatic invasive species are listed and regulated by Nebraska Game and Parks Commission.

ABSINTH WORMWOOD • AMUR HONEYSUCKLE • AUTUMN OLIVE • BRITTLE NAIAD • CALLERY …

Thermal Tolerance Limits Of The Chinese Mystery Snail (Bellamya Chinensis): Implications For Management, Jessica L. Burnett, Kevin L. Pope, Alec Wong, Craig R. Allen, Danielle Haak, Bruce J. Stephen, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail, Bellamya chinensis (Gray, 1834) is a gastropod native to East Asia and is considered an invasive species in North America where its impacts on native species and ecosystems are not well understood. Scientific literature describing its biology and life history are sparse. Thermal tolerance limits, or the maximum and minimum temperature under which a species can survive, are key to identifying the potential geographical range of a species. The ability of managers to control invasive species is directly impacted by the thermal tolerance limits of a species. We attempted to identify the thermal tolerance limits of …

The Effect Of Size On Juvenile Green Sturgeon (Acipenser Medirostris) Behavior Near Water-Diversion Fish Screens, Jamilynn B. Poletto, Dennis E. Cocherell, Natalie Ho, Joseph J. Cech Jr., A. Peter Klimley, Nann A. Fangue

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Anthropogenic water management projects and facilities that alter the local and regional hydrology of riverine environments greatly influence the behavior, physiology, and survival of native fishes. To mitigate for losses of native fishes at these structures, many are outfitted with fish-exclusion screens to reduce entrainment. The effect of fish size and age on behavior near fish screens, however, is largely unknown. Therefore, we tested two size classes of juvenile green sturgeon (Acipenser medirostris; small, early juveniles: 9.2 ± 0.2 cm fork length [FL], 6.9 ± 0.3 g; intermediate juveniles: 18.8 ± 0.2 cm FL, 36.9 ± 0.8 g) …

Resilience In Environmental Risk And Impact Assessment: Concepts And Measurement, David G. Angeler, Craig R. Allen, Ahjond S. Garmestani, Kevin L. Pope, Dirac L. Twidwell Jr, Micro Bunschuh

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Different resilience concepts have different assumptions about system dynamics, which has implications for resilience-based environmental risk and impact assessment. Engineering resilience (recovery) dominates in the risk assessment literature but this definition does not account for the possibility of ecosystems to exist in multiple regimes. In this paper we discuss resilience concepts and quantification methods. Specifically, we discuss when a system fails to show engineering resilience after disturbances, indicating a shift to a potentially undesired regime. We show quantification methods that can assess the stability of this new regime to inform managers about possibilities to transform the system to a more …

Agroecology For The Shrinking City, Dustin L. Herrmann, Wen-Ching Chuang, Kristen Schawrz, Timothy M. Bowles, Ahjond S. Garmestani, William D. Shuster, Tarsha Eason, Matthew E. Hopton, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Many cities are experiencing long-term declines in population and economic activity. As a result, frameworks for urban sustainability need to address the unique challenges and opportunities of such shrinking cities. Shrinking, particularly in the U.S., has led to extensive vacant land. The abundance of vacant land reflects a loss of traditional urban amenities, economic opportunity, neighbors, businesses, and even basic city services and often occurs in neighborhoods with socially and economically vulnerable or underserved populations. However, vacant land also provides opportunities, including the space to invest in green infrastructure that can provide ecosystem services and support urban sustainability. Achieving desirable …

Opportunities And Challenges For Big Data Ornithology, Frank A. La Sorte, Christopher A. Lepczyk, Jessica L. Burnett, Allen H. Hurlbert, Morgan W. Tingley, Benjamin Zuckerberg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Recent advancements in information technology and data acquisition have created both new research opportunities and new challenges for using big data in ornithology. We provide an overview of the past, present, and future of big data in ornithology, and explore the rewards and risks associated with their application. Structured data resources (e.g., North American Breeding Bird Survey) continue to play an important role in advancing our understanding of bird population ecology, and the recent advent of semistructured (e.g., eBird) and unstructured (e.g., weather surveillance radar) big data resources has promoted the development of new empirical perspectives that are generating novel …

A Framework For Tracing Social–Ecological Trajectories And Traps In Intensive Agricultural Landscapes, Daniel R. Uden, Craig R. Allen, Francisco Munoz-Arriola, Gengxin Ou, Nancy Shank

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Charting trajectories toward sustainable agricultural development is an important goal at the food–energy–water–ecosystem services (FEWES) nexus of agricultural landscapes. Social–ecological adaptation and transformation are two broad strategies for adjusting and resetting the trajectories of productive FEWES nexuses toward sustainable futures. In some cases, financial incentives, technological innovations, and/or subsidies associated with the short-term optimization of a small number of resources create and strengthen unsustainable feedbacks between social and ecological entities at the FEWES nexus. These feedbacks form the basis of rigidity traps, which impede adaptation and transformation by locking FEWES nexuses into unsustainable trajectories characterized by control, stability, and efficiency, …

Quantifying Uncertainty And Trade-Offs In Resilience Assessments, Craig R. Allen, Hannah E. Birgé, David G. Angeler, Craig A. Arnold, Brian C. Chaffin, Daniel A. Decaro, Ahjond S. Garmestani, Lance Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Several frameworks have been developed to assess the resilience of social-ecological systems, but most require substantial data inputs, time, and technical expertise. Stakeholders and practitioners often lack the resources for such intensive efforts. Furthermore, most end with problem framing and fail to explicitly address trade-offs and uncertainty. To remedy this gap, we developed a rapid survey assessment that compares the relative resilience of social-ecological systems with respect to a number of resilience properties. This approach generates large amounts of information relative to stakeholder inputs. We targeted four stakeholder categories: government (policy, regulation, management), end users (farmers, ranchers, landowners, industry), agency/public …

A Method To Detect Discontinuities In Census Data, Chris Barichievy, David G. Angeler, Tarsha Eason, Ahjond S. Garmestani, Kirsty L. Nash, Craig A. Stow, Shana Sundstrom, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The distribution of pattern across scales has predictive power in the analysis of complex systems. Discontinuity approaches remain a fruitful avenue of research in the quest for quantitative measures of resilience because discontinuity analysis provides an objective means of identifying scales in complex systems and facilitates delineation of hierarchical patterns in processes, structure, and resources. However, current discontinuity methods have been considered too subjective, too complicated and opaque, or have become computationally obsolete; given the ubiquity of discontinuities in ecological and other complex systems, a simple and transparent method for detection is needed. In this study, we present a method …

Effects Of Large-Scale Wetland Loss On Network Connectivity Of The Rainwater Basin, Nebraska, Bram H. F. Verheijen, Dana M. Varner, David A. Haukos

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Context The Rainwater Basin region in south-central Nebraska supports a complex network of spatiallyisolated wetlands that harbor diverse floral and faunal communities. Since European settlement, many wetlands have been lost from the network, which has increased distances among remaining wetlands. As a result, populations of wildlife species with limited dispersal capabilities may have become isolated and face greater local extinction risks.

Objectives We compared the pre-European settlement and current extent of the Rainwater Basin network to assess the effects of wetland losses on network connectivity for a range of maximum dispersal distances.

Methods We constructed network models for a range …

Synchrony - An Emergent Property Of Recreational Fisheries, Mark A. Kaemingk, Christopher J. Chizinski, Keith L. Hurley, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

No abstract provided.

Bipartite Networks Improve Understanding Of Effects Of Waterbody Size And Angling Method On Angler–Fish Interactions, Christopher J . Chizinski, Dustin R. Martin, Daizaburo Shizuka, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Networks used to study interactions could provide insights to fisheries. We compiled data from 27 297 interviews of anglers across waterbodies that ranged in size from 1 to 12 113 ha. Catch rates of fish species among anglers grouped by species targeted generally differed between angling methods (bank or boat). We constructed angler–catch bipartite networks (angling method specific) between anglers and fish and measured several network metrics. There was considerable variation in networks among waterbodies, with multiple metrics influenced by waterbody size. Number of species-targeting angler groups and number of fish species caught increased with increasing waterbody size. Mean number …

Variation In Angler Distribution And Catch Rates Of Stocked Rainbow Trout In A Small Reservoir, Brian S. Harmon, Dustin R. Martin, Christopher J . Chizinski, K. L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We investigated the spatial and temporal relationship of catch rates and angler party location for two days following a publicly announced put-and-take stocking of rainbow trout (Oncorhynchus mykiss). Catch rates declined with time since stocking and distance from stocking. We hypothesized that opportunity for high catch rates would cause anglers to fish near the stocking location and disperse with time, however distance between angler parties and stocking was highly variable at any given time. Spatially explicit differences in catch rates can affect fishing quality. Further research could investigate the variation between angler distribution and fish distribution within a …

Population Characteristics Of Shovelnose Sturgeon During Low- And High-Water Conditions In The Lower Platte River, Nebraska, Jeremy J. Hammen, Martin J. Hamel, Matthew L. Rugg, Edward J. Peters, Mark A. Pegg

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Cycles of low- and high-water periods (i.e., years) in river systems are natural occurrences, but understanding how cyclical climatological patterns affect fishes, especially long-lived species, is unclear. We assessed Shovelnose Sturgeon population dynamics between a period of low- (2001-2004) and high- (2009-2012) water years in the lower Platte River, Nebraska. Low-flow periods in the lower Platte River can cause disconnection(s) between upstream and downstream reaches resulting in isolated pools and elevated water temperatures leading to stressful situations for aquatic life and possible mortality. Our data show no measurable differences between key population indices between flow condition periods which is consistent …

Resilience Concepts In Psychiatry Demonstrated With Bipolar Disorder, David G. Angeler, Craig R. Allen, Maj-Liz Persson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Background: The term resilience describes stress–response patterns of subjects across scientific disciplines. In ecology, advances have been made to clearly distinguish resilience definitions based on underlying mechanistic assumptions. Engineering resilience (rebound) is used for describing the ability of subjects to recover from adverse conditions (disturbances), and is the rate of recovery. In contrast, the ecological resilience definition considers a systemic change: when complex systems (including humans) respond to disturbances by reorganizing into a new regime (stable state) where structural and functional aspects have fundamentally changed relative to the prior regime. In this context, resilience is an emergent property of complex …

Our Changing Climate, David R. Easterling, David W. Fahey, Katherine Hayhoe, Sarah Doherty, James P. Kossin, William V. Sweet, Russell S. Vose, Michael F. Wehner, Donald J. Wuebbels

National Oceanographic and Atmospheric Administration: Technical Reports and Related Materials

This chapter is based on the Climate Science Special Report (CSSR), which is Volume I of the Fourth National Climate Assessment (available at science2017.globalchange.gov). The Key Messages and the majority of the content represent the highlights of CSSR, updated with recent references relevant to these topics. The interested reader is referred to the relevant chapter(s) in CSSR for more detail on each of the Key Messages that follow.

Diversity And Phylogenetic Relationships Of European Species Of Crepidostomum Braun, 1900 (Trematoda: Allocreadiidae) Based On Rdna, With Special Reference To Crepidostomum Oschmarini Zhokhov & Pugacheva, 1998, Romualda Petkevičiūtė, Virmantas Stunžėnas, Alexander E. Zhokhov, Larisa G. Poddubnaya, Gražina Stanevičiūtė

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Background

Within the genus Crepidostomum Braun, 1900, identification of species and taxonomic decisions made only on the basis of adult morphology have resulted in great problems associated with evaluating actual diversity and validity of species. Life cycle data, while equal in importance to adult characters, are scarce, controversial or incomplete for most Crepidostomum spp. In this study, rDNA sequences generated from adult and larval Crepidostomum spp. and some other allocreadiid species were analyzed to reveal the diversity and phylogenetic relationships of the species and their host range. Detailed morphological description based on light microscopy, SEM tegumental surface topography and genetic …