Aquaculture and Fisheries Commons^™

A Population Model For Walleye In Nebraska Irrigation Reservoirs, Robert A. Kill

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

Understanding how and why fish population size changes between years is a central theme in fisheries ecology. Fishery agencies have limited time and financial resources, thus there is a need for a quantitative way to direct the limited time and financial resources so agencies can manage fisheries more efficiently. I developed a tool for fishery managers that synthesizes common population indices and evaluated the relative importance of those indices given varying uncertainty in age-0 walleye Sander vitreus survival. Under most circumstances, I determined that resources are best utilized in reducing age-0 survival uncertainty when understanding walleye population growth. I applied …

Determining Scaphirhynchus Sturgeon Population Demographics And Dynamics: Implications For Range-Wide Management, Recovery, And Conservation, Martin J. Hamel

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

Sturgeons (Acipenseridae) have experienced world-wide declines as a result of anthropogenic effects such as over-harvest, habitat degradation, altered flow regimes, and pollution. Nearly all European and Asian sturgeon species have experienced population declines and have subsequently been classified as either threatened or endangered. North American sturgeons have experienced a similar plight in that all eight native sturgeon species are listed as endangered, threatened, or of special concern. Direct linkages between North American sturgeon declines and anthropogenic effects are difficult to assess due to scale considerations, fluctuating environmental conditions, difficulty in capture, and the interaction of all these effects. To recover, …

Walleye And White Bass Recruitment In Southwest Nebraska Irrigation Reservoirs, Jason Andrew Deboer

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

Walleye Sander vitreus and white bass Morone chrysops are among the most popular sportfish in the reservoirs of the Great Plains. Despite considerable effort by the Nebraska Game and Parks Commission stocking walleye and managing reservoirs for walleye and white bass, populations of walleye and white bass in southwest Nebraska reservoirs are dynamic, as erratic recruitment has led to “boom and bust” fisheries for these two species. We investigated 1) factors regulating walleye and white bass recruitment during an 18-year period at five reservoirs, and 2) walleye spawning ecology at two reservoirs that differ in their degree of environmental variability. …

Reported Incidences Of Parasitic Infections In Marine Mammals From 1892 To 1978, John R. Felix

Zea E-Books Collection

The role of parasites in the lives and deaths of marine mammals has been scrutinized by biologists for decades, but the scientific literature prior to 1978 has been difficult to acquire and time-consuming to search. Now this new and extensive bibliography gives researchers a convenient resource for reviewing the classical literature on parasites of marine mammals so that historical infection prevalence and geographical distribution can be easily and properly assessed. This book contains detailed information about accepted (or suspected) taxonomic synonyms and geographical information about the host and/or parasite, covering the parasite groups Acanthocephala, Acarina, Anoplura, Cestoda, Nematoda, and Trematoda, …

Shovelnose Sturgeon Reproductive Ecology In The Lower Platte River, Nebraska, Mathew L. Rugg

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

Biodiversity and abundance of freshwater organisms are experiencing drastic declines. Anthropogenic disturbances have altered the natural flow regimes of large rivers, and have led to declines in species that rely on elements of natural flow. Similarly, shovelnose sturgeon distribution has diminished in the last 100 years due to habitat alteration, overharvest, and water contamination. To fully understand the status and viability of a fish population, basic knowledge of a fish’s reproductive strategy is needed. Aspects of reproduction that should be understood to manage for sustainability include maturation, fecundity, and spawning dynamics. There is currently little published information on age/size of …

Exploitation Of Channel Catfish In Nebraska Flood-Control Reservoirs, Christopher Lee Wiley

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

Channel catfish Ictalurus punctatus, is a popular sportfish in North America, and is the third most-sought fish species in Nebraska. Exploitation rates of channel catfish populations have been estimated to be substantial in states neighboring Nebraska. Despite the popularity of channel catfish, little is known about the exploitation of channel catfish populations in Nebraska. The objectives of this study were to estimate the exploitation rates of channel catfish populations, identify the length bias of angling for channel catfish, and identify the self-imposed length limits for channel catfish at flood-control reservoirs of Nebraska. The software package Program Mark was used to …

Review Of The Negative Influences Of Non-Native Salmonids On Native Fish Species, Kelly C. Turek, Mark A. Pegg, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Non-native salmonids are often introduced into areas containing species of concern, yet a comprehensive overview of the short- and long-term consequences of these introductions is lacking in the Great Plains. Several authors have suggested that non-native salmonids negatively influence species of concern. The objective of this paper is to review known interactions between non-native salmonids and native fishes, with a focus on native species of concern. After an extensive search of the literature, it appears that in many cases non-native salmonids do negatively influence species of concern (e.g., reduce abundance and alter behavior) via different mechanisms (e.g., predation and competition). …

Assessment Of A Rotenone Application Event At Mormon Island West Lake In Central Nebraska, Keith D. Koupal, Brian C. Peterson, Casey W. Schoenebeck

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Fisheries managers applied rotenone to Mormon Island West in August of 2010 to renovate a fish community that was hypothesized to be unbalanced (i.e., dominated with gizzard shad and common carp) based on standardized survey results. We estimated species-specific biomass following the lake renovation to provide a baseline biomass estimate for a sand pit lake and to evaluate the effectiveness of standardized sampling gears. Gizzard shad (Dorosoma cepedianum) were abundant in all sampling gears, but mostly stock-size (>175 mm total length) and larger individuals were caught in gill and trap nets and sub-stock (≤175 mm total length) …

Behavioural Salinity Preferences Of Juvenile Green Sturgeon Acipenser Medirostris Acclimated To Fresh Water And Full-Strength Salt Water, J. B. Poletto, D. E. Cocherell, A. P. Klimley, J. J. Cech Jr., N. A. Fangue

School of Natural Resources: Faculty Publications

To quantify the salinity preference of juvenile green sturgeon Acipenser medirostris, two groups of A. medirostris [140 days post hatch (dph); total length (L_T) 38.0–52.5 cm] were acclimated to either near fresh water (mean ± S.E. salinity = 3.2 ± 0.6) or full-strength salt water (34.1 ± 1.2) over 8 weeks. Following acclimation, the two groups were divided into experimental and control groups, where experimental A. medirostris from both freshwater and saltwater acclimations were individually introduced (200–220 dph) into a rectangular salinity-preference flume (maximum salinity gradient: 5–33). Control A. medirostris were presented with only their acclimation …

Scenarios Of Bioenergy Development Impacts On Regional Groundwater Withdrawals, Daniel R. Uden, Craig R. Allen, Rob B. Mitchell, Qingfeng Guan, Tim D. Mccoy

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Irrigation increases agricultural productivity, but it also stresses water resources (Huffaker and Hamilton 2007). Drought and the potential for drier conditions resulting from climate change could strain water supplies in landscapes where human populations rely on finite groundwater resources for drinking, agriculture, energy, and industry (IPCC 2007). For instance, in the North American Great Plains, rowcrops are utilized for livestock feed, food, and bioenergy production (Cassman and Liska 2007), and a large portion is irrigated with groundwater from the High Plains aquifer system (McGuire 2011). Under projected future climatic conditions, greater crop water use requirements and diminished groundwater recharge rates …

Rainwater Basin Wetland Inundation Decision Support System Guide, Christopher F. Jorgensen, Andy A. Bishop, Daniel R. Uden, Roger Grosse

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Rainwater Basin region of south-central Nebraska, U.S.A., is a critical stopover location for migratory waterfowl, waterbirds and shorebirds traveling along the Central Flyway. The ephemeral playa wetlands in the region serve as spring staging areas, providing critical habitat for migrating birds to rest, feed and establish pairs before resuming their northward migration to the breeding grounds. Collectively, the playa wetlands found in the region form the Rainwater Basin Wetland Complex, encompassing a 6,150 square-mile area of rolling loess plains that extend over 21 counties. Analyses of the State’s historic soil surveys (1910-1917), National Wetland Inventory (NWI; 1980-1982; U.S. Geological …

The Feasibility Of Producing Adequate Feedstock For Year-Round Cellulosic Ethanol Production In An Intensive Agricultural Fuelshed, Daniel R. Uden, Robert B. Mitchell, Craig R. Allen, Qingfeng Guan, Tim D. Mccoy

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

To date, cellulosic ethanol production has not been commercialized in the United States. However, government mandates aimed at increasing second-generation biofuel production could spur exploratory development in the cellulosic ethanol industry. We conducted an in-depth analysis of the fuelshed surrounding a starch-based ethanol plant near York, Nebraska that has the potential for cellulosic ethanol production. To assess the feasibility of supplying adequate biomass for year-round cellulosic ethanol production from residual maize (Zea mays) stover and bioenergy switchgrass (Panicum virgatum) within a 40-km road network service area of the existing ethanol plant, we identified ∼14,000 ha of marginally productive cropland within …

Survival And Behavior Of Chinese Mystery Snails (Bellamya Chinensis) In Response To Simulated Water Body Drawdowns And Extended Air Exposure, Kody M. Unstad, Daniel R. Uden, Craig R. Allen, Noelle M. Chaine, Danielle M. Haak, Robert A. Kill, Kevin L. Pope, Bruce J. Stephen, Alec Wong

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Nonnative invasive mollusks degrade aquatic ecosystems and induce economic losses worldwide. Extended air exposure through water body drawdown is one management action used for control. In North America, the Chinese mystery snail (Bellamya chinensis) is an invasive aquatic snail with an expanding range, but eradication methods for this species are not well documented. We assessed the ability of B. chinensis to survive different durations of air exposure, and observed behavioral responses prior to, during, and following desiccation events. Individual B. chinensis specimens survived air exposure in a laboratory setting for > 9 weeks, and survivorship was greater among adults …

Degree-Day Accumulation Influences Annual Variability In Growth Of Age-0 Walleye, Christopher S. Uphoff, Casey W. Schoenebeck, W. Wyatt Hoback, Keith D. Koupal, Kevin L. Pope

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The growth of age-0 fishes influences survival, especially in temperate regions where size-dependent over-winter mortality can be substantial. Additional benefits of earlier maturation and greater fecundity may exist for faster growing individuals. This study correlated prey densities, growing-degree days, water-surface elevation, turbidity, and chlorophyll a with age-0 walleye Sander vitreus growth in a south-central Nebraska irrigation reservoir. Growth of age-0 walleye was variable between 2003 and 2011, with mean lengths ranging from 128 to 231 mm by fall (September 30th–October 15th). A set of a priori candidate models were used to assess the relative support of explanatory variables using Akaike’s …

Enamel-Based Mark Performance For Marking Chinese Mystery Snail Bellamya Chinensis, Alec Wong, Craig R. Allen, Noelle M. Hart, Danielle M. Haak, Kevin L. Pope, Nicholas A. Smeenk, Bruce J. Stephen, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The exoskeleton of gastropods provides a convenient surface for carrying marks, and in the interest of improving future marking methods our laboratory assessed the performance of an enamel paint. The endurance of the paint was also compared to other marking methods assessed in the past. We marked the shells of 30 adult Chinese mystery snails Bellamya chinensis and held them in an aquarium for 181 days. We observed no complete degradation of any enamel-paint mark during the 181 days. The enamel-paint mark was superior to a nail-polish mark, which lasted a median of 100 days. Enamel-paint marks also have a …

Mortality Estimate Of Chinese Mystery Snail, Bellamya Chinensis (Reeve, 1863) In A Nebraska Reservoir, Danielle M. Haak, Noelle M. Chaine, Bruce J. Stephen, Alec Wong, Craig R. Allen

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail (Bellamya chinensis) is an aquatic invasive species found throughout the USA. Little is known about this species’ life history or ecology, and only one population estimate has been published, for Wild Plum Lake in southeast Nebraska. A recent die-off event occurred at this same reservoir and we present a mortality estimate for this B. chinensis population using a quadrat approach. Assuming uniform distribution throughout the newly-exposed lake bed (20,900 m2), we estimate 42,845 individuals died during this event, amounting to approximately 17% of the previously-estimated population size of 253,570. Assuming uniform distribution throughout all …

Effects Of Simulated Angler Capture And Live-Release Tournaments On Walleye Survival, John H. Loomis, Harold L. Schramm Jr., Bruce Vondracek, Patrick D. Gerard, Christopher J. Chizinski

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

We examined the effects of acclimation water temperature, live-well (LW) water temperature, and LW dissolved oxygen (DO) concentration on survival of adult Walleyes Sander vitreus subjected to simulated tournament conditions (angling, LW confinement, and weigh-in procedures) under controlled laboratory conditions. We tested three acclimation temperatures (12, 18, and 24◦C), and three LWtemperature differentials (Delta T=−4, 0, and +4◦C) were tested at each acclimation temperature. Survival was monitored after 8 h of LW confinement and during a 5-d retention period in 1,700-L tanks. None of the Walleyes that were acclimated to 24◦C and subjected to simulated tournament procedures survived the 5-d …

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

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail (Bellamya chinensis) is a non-indigenous, invasive species in freshwater ecosystems of North America. We provide fecundity estimates for a population of these snails in a Nebraska reservoir. We dissected 70 snails, of which 29 were females. Nearly all female snails contained developing young, with an average of 25 young per female. Annual fecundity was estimated at between 27.2 and 33.3 young per female per year. Based on an estimated adult population and the calculated fecundity, the annual production for this reservoir was between 2.2 and 3.7 million young.

Predictors Of Regional Establishment Success And Spread Of Introduced Non-Indigenous Vertebrates, Criag R. Allen, Kristine T. Nemec, Donald A. Wardwell, Justin D. Hoffman, Mathew L. Brust, Karie L. Decker, Daniel Fogell, Jennifer Hogue, Aaron Lotz, Thaddeus Miller, Marcy Pummill, Luis E. Ramirez-Yañez, Daniel R. Uden

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Aim To provide the first analysis of predictors of both establishment and spread, both within and across taxa, for all vertebrate taxa within a region.We used Florida, USA, as our study system because it has a well-documented history of introduction and invasion, and is a hotspot for biological invasions.

Location Florida, USA.

Methods We analysed non-indigenous species (NIS) data from peninsular Florida – which included both successful and unsuccessful introductions from all vertebrate classes – to determine the best predictors of both establishment and spread for fish (65 species), herpetofauna (63 species), birds (71 species) and mammals (25 species). We …