Aquaculture and Fisheries Commons^™

Growth Rate Of Copepods In The San Francisco Bay, Brooke Bemowski, Wim Kimmerer, Toni Ignoffo

STAR Program Research Presentations

The San Francisco Estuary is a complex ecosystem. A key part of the foodweb are zooplankton crustaceans, specifically copepods. Many fish, especially the endangered delta smelt, rely on copepods as a food source. Measuring the growth of copepods assists in predictions if enough food is available for delta smelt. Traditionally growth rate is measured through lengthy and involved processes. The objective of this research project is to develop an imaging process to analyze biomass of copepods more efficiently. For this research, field samples of copepods were collected and grown over three days. Subsamples were taken and preserved at three predetermined …

Interaction, Intracellular Replication And Cytopathic Effect Of A Highly Pathogenic Chilean Isolate Of Piscirickettsia Salmonis In Shk-1 Cells, Constanza Sanhueza, Cristian Oliver, Karla Valenzuela, Harold Oliva, Samuel Valdebenito, Alejandro Yáñez

2nd International Conference of Fish & Shellfish Immunology

No abstract provided.

Connecting Rivers For Healthy Ocean Fisheries, Catherine Schmitt

Maine Sea Grant Publications

Across Maine, communities and land owners are reconnecting rivers and streams by improving road crossings, fixing broken culverts, and removing dams and other barriers. There are many reasons for doing this work, including preventing costly repairs associated with flooding and washouts, enhancing water quality, increasing wildlife habitat, and restoring fish populations. Connecting Rivers explores some of the ways that streams connect inland lakes and forests and the sea. This first fact sheet in the series focuses on connections between populations of migratory river fish (alewives and blueback herring) and groundfish (e.g., cod).

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 …

A New Snail-Eating Turtle Of The Genus Malayemys Lindholm, 1931 (Geoemydidae) From Thailand And Laos, Timothy R. Brophy, M. Sumontha, K. Kunya, S. Wiboonatthapol, O.S.G. Pauwels

Faculty Publications and Presentations

We describe a snail-eating turtle, Malayemys isan sp. nov., from the Mekong River Basin in northeastern Thailand (Nong Bua Lamphu, Nong Khai and Udon Thani provinces) and the adjacent Vientiane area in Laos. The new species is readily distinguishable from M. subtrijuga by its two (vs. six to nine) nasal stripes, and from both M. subtrijuga and M. macrocephala by its thin, often discontinuous, infraorbital stripe that never reaches the loreal seam. This geographically-restricted new species is sold in several food markets throughout the species‟ distribution and is in urgent need of conservation measures.

Zebra Mussel (Dreissena Polymorpha) Affects The Feeding Ecology Of Early Stage Striped Bass (Morone Saxatilis) In The Hudson River Estuary, Michael G. Smircich, David L. Strayer, Eric T. Schultz

EEB Articles

Variability in the feeding ecology of young fishes over short and long time scales in estuaries is likely to affect population dynamics. We studied 14 years of early stage Striped Bass feeding ecology in the Hudson River Estuary over a 25-year time span, including years in which invasive zebra mussels markedly altered energy flow within the estuary. We predicted that feeding success would be low and that diet composition would be altered during years of high zebra mussel impact, particularly in upriver locations where mussels occur. Feeding success in the short term was indicated by volume of gut contents and …

Exposing Artemia Salina To Chattonella Subsalsa: A General Toxicity Test, Nicholas Picha

Bridges: A Journal of Student Research

The raphidophyte Chattonella subsalsa has been reported to cause harmful algal blooms in every major ocean. In South Carolina, C. subsalsa blooms have been observed in brackish stormwater detention ponds as well as estuarine waters neighboring urbanized areas. Blooms frequently cause fish kills although the fish kill mechanism of C. subsalsa is currently unknown. In many harmful species, the lethality of algal cells is thought to correspond with algal growth phase. Algal growth is known to progress through five distinct phases; lag, early exponential, late exponential, stationary, and decline. In nature, harmful algal blooms commonly occur in the late exponential …

Effects Of Chemical Preservatives On Weights And Lengths Of Bluegill Larvae, Scott M. Welch, Gregory A. Dudenhoeffer, Thomas R. Omara-Alawla

Cooperative Extension Research Publications

Measuring the lenghts and weights of live fish larvae can be tedious and time-consuming. This constraint could be alleviated by preserving the fish larvae in appropriate chemicals for later measurements. There is little or no information on the effects of preservatives on Bluegill larvae. The objective of this study was to determine the effects of five different common preservatives on Bluegill larvae. Individual weights and lengths of fish were measured and then the larvae were preserved for 7 or 26 days. Preservatives were 5% formalin, 10% formalin, 30% ethanol at -19 *C, 70% ethanol, and 90% ethanol. Preliminary average weights …

Fish Lack The Brains And The Psychology For Pain, Stuart W.G. Derbyshire

Animal Sentience

Debate about the possibility of fish pain focuses largely on the fish’s lack of the cortex considered necessary for generating pain. That view is appealing because it avoids relatively abstract debate about the nature of pain experience and subjectivity. Unfortunately, however, that debate cannot be entirely avoided. Subcortical circuits in the fish might support an immediate, raw, “pain” experience. The necessity of the cortex only becomes obvious when considering pain as an explicitly felt subjective experience. Attributing pain to fish only seems absurd when pain is considered as a state of explicit knowing.

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

US Army Corps of Engineers

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 …

Assessing Freshwater Mussels (Bivalvia: Unionidae) In South Dakota And Identifying Drivers Of Assemblage Variation, Kaylee L. Faltys

Electronic Theses and Dissertations

Native freshwater mussels (Family: Unionidae) are among the most threatened groups of freshwater fauna on Earth. Approximately 35 species have gone extinct since the 1900s and 72% of remaining species are considered endangered, threatened, or species of special concern. Unionid research can begin by establishing species presence and distributions via surveys. Objectives for this study were to 1) implement the first comprehensive unionid survey for South Dakota to assess distribution, composition, and decline, 2) estimate assemblage density and determine local versus broad scale habitat drivers of assemblage variation, and 3) determine areas of unionid conservation priority in South Dakota. Mussels …

A Comparative Analysis Of The Metabolism And Energetics Of Darters (Percidae), Emma Kirsten Kist

Theses, Dissertations and Capstones

Ecological niche theory suggests two species cannot live in the same ecological niche and differences should exist among species that appear to cohabitate. Variations in physiology and behavior that potentially enable species coexistence can be reflected in metabolism. This study investigated coexisting darter fishes by measuring the metabolism of greenside (Etheostoma blennioides) and variegate (E. variatum) darters over 48 h using intermittent-flow respirometry. Activity was analyzed using time-lapse videos. E. blennioides mean metabolic rate (154.64 ± SE 52.54 mg O2·kg-1 ·hr-1 ; n=14; p=0.0006) was significantly greater than and varied more than E. variatum’s mean rate (92.51 ± SE 32.70 …

Hibernacula Site Selection Of The Eastern Box Turtle, Terrapene C. Carolina, In A West Virginia Population, Benjamin Owen Koester

Theses, Dissertations and Capstones

Eastern Box Turtles (Terrapene c. carolina) are a terrestrially hibernating reptile found throughout the eastern United States. Despite their prevalence, little, outside of anecdotal observations, is known about their hibernacula selection. This study examines if they preferentially select hibernacula locations, and if so, what characteristics they select in a West Virginia population. Over the course of two years, radio-tagged turtles (n=12) were followed into hibernation in Wayne County, WV. Upon entering hibernation, ~36 data point were collected in a grid-like fashion around the hibernacula, with an additional point collected at the hibernacula. At each point, seven variables were recorded: soil …

Testing The Efficacy Of Anuran Callback Surveys, Matthew S. Grisnik

Theses, Dissertations and Capstones

Monitoring programs often suffer from imperfect detection resulting in skewed population estimates, biased estimates of changes in occupancy over time, and can result in an underestimated proportion of area occupied (PAO) by a species. To increase the detection probability, researchers must increase sampling both spatially and temporally. Callback surveys are an active form of sampling that have been used to monitor many avian and mammal species. During callback surveys, the call of a conspecific male is projected with the intention of increasing probability of detection by eliciting a response from territorial males. These methods work for organisms that establish breeding …

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 …

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 …

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 …

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 …

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%; …