Laboratory and Basic Science Research Commons^™

Walleye Sander Vitreus Visceral Fat Accumulation, Cole Daleiden, Seth Renner

Journal of Earth and Life Science

For ectothermic species, proper lipid retention is critical to surviving in regions with limited growing seasons. Visceral fat is the dominant form of this energy storage in fish. Build up and depletion of these lipids occur seasonally as activity levels change throughout winter and spring. Due to this annual pattern, the purpose of this study is to determine a trend in the amount of visceral fat Walleye Sander vitreus accumulate in a time of year when metabolic rates are low and transition into the spawning process has yet to occur. Angling was the method of capture conducted during the months …

The Cardiovascular Response To Acute Hypoxic Conditions In Danio Rerio, Bryce Fetterman

Williams Honors College, Honors Research Projects

There are many fish that can withstand hypoxia levels. One in particular is the zebrafish (Danio rerio). The zebrafish is a small-sized, Cyprinid teleost fish, and has been used in a laboratory setting for many reasons. A few reasons being that they are widely available, easy to care for, and the cost for these fish are very low. There are various reasons why these fish are used as a model. One main reason is because their cardiovascular system is one of the first developing organs. This allows for better resolution when studying the cardiovascular system. The purpose of …

Determination Of Iron-Reducing Bacterial Activities In Lake Sediments., Alexandra Kahn

Williams Honors College, Honors Research Projects

Algal blooms are growing rampantly in lacustrine systems due to an increase of phosphorus, a nutrient for algae. Phosphorus is being released into the environment causing overpopulation and eutrophication which damages the ecosystem. The availability of phosphorus is affected by the solubility of iron which is regulated through iron reducing and iron oxidizing bacteria. Phosphorus adheres to insoluble Fe(III), which prohibits algae from utilizing it, while phosphorus does not attach to soluble Fe(II) and therefore it remains available to algae. The purpose of this study was to determine how bacteria influence iron solubility and what are the ideal environmental conditions …

Antifungal Defense Molecules From Bacterial Symbionts Of North American Trachymyrmex Ants, Georgia Scherer

CMC Senior Theses

Defensive symbioses, in which microbes provide molecular defenses for an animal host, hold great potential as untapped sources of therapeutically useful antibiotics. Fungus-growing ants use antifungal defenses from bacterial symbionts to suppress pathogenic fungi in their nests. Preliminary chemical investigations of symbiotic bacteria from this large family of ants have uncovered novel antifungal molecules with therapeutic potential, such as dentigerumycin and selvamicin.

In this study, the bacterial symbionts of North American Trachymyrmex fungus-growing ants are investigated for antifungal molecules. Plate-based bioassays using ecologically-relevant fungal pathogens confirmed that these bacteria have antifungal activity. In order to purify and identify the antifungal …

Acclimation, Long-Term Repeatability, And Phenotypic Correlations Of Aerobic Metabolic Traits In The Gulf Killifish, Fundulus Grandis, Jessica E. Reemeyer

LSU New Orleans Theses and Dissertations

This research examined the effects of acclimation to lowered salinity, elevated temperature, and hypoxia on aerobic metabolism of the Gulf killifish, Fundulus grandis, a common estuarine resident of the Gulf of Mexico. Standard metabolic rate (SMR), maximum metabolic rate (MMR), absolute aerobic scope (AAS), and critical oxygen tension (P_crit) were each influenced by one or more acclimation treatments. Assessing the consistency of these traits measured in the same individuals over time, all were found to be significantly repeatable with no indication that the repeatability of any traits was affected by acclimation conditions. Significant correlations were found between …

Effects Of Reduced Ph On Health Biomarkers Of The Seagrass Cymodocea Nodosa, Regan A. Mcenaney

DePaul Discoveries

Ocean acidification is a growing problem that may affect many marine organisms in the future. Within 100 years the pH of the ocean is predicted to decrease to 7.8, from the current ocean pH of around 8.1. Using phenolic acid levels as a stress indicator as well as respiration and chlorophyll content as a measure of health, the effect of lowering pH was tested on the seagrass, Cymodocea nodosa, in a controlled environment. Plant samples, water, and soil were taken from the Bay of Cádiz, Spain, and placed in aquaria in a temperature-controlled room. One control group was left …

Spatial And Temporal Variability In Post-Larval Yellow Perch Density, Steve Hauschildt

Biology Graduate Theses

Yellow Perch Perca flavescens are important as forage for other species and for sport fishing in many northern lakes. However, estimating post-larval Yellow Perch populations can be difficult because of many environmental factors that cause unexplained variation. The objective of this study was to help reduce unexplained variation by determining a post-larval Yellow Perch population density estimate on Blackduck Lake, MN, provide guidance to help determine the number of trawls required for trawling-based recruitment indices to achieve varying levels of precision, and test for the effects of wind speed and direction on post-larval Yellow Perch spatial variability. This study estimated …

Effects Of Rainbow Trout On Brook Trout Population Size In Tributaries To Lake Superior In Cook County, Minnesota, Craig Tangren

Journal of Earth and Life Science

This study looked at the effects of Rainbow Trout stocking on the size of Brook Trout populations above migratory barriers. Linear mixed effects models were used to determine if there was a relationship between Brook Trout and Rainbow Trout catch rates. Age 1 or older Brook Trout populations were influenced by relative abundance of age 1 or older Rainbow Trout, according to the best supported model based on AIC scores. Population responses varied by stream, ranging along a gradient from high catch rates with a positive relationship to a negative relationship with low relative abundances. Streams with a positive relationship …

Changes In Walleye Fecundity And Egg Size Before, During, And After Rehabilitation Of The Red Lakes Fishery, Benjamin J. Miller, Benjamin D. Erb

Journal of Earth and Life Science

The Red Lakes in northern Minnesota experienced a major Walleye Sander vitreus fishery crash in the late 20th century, but has since recovered to record abundances and supports a major commercial and recreational fishery. Fecundity is an integral aspect of recruitment that can contribute greatly to the understanding of fishery population dynamics. To elucidate the effects of varying Walleye densities and exploitation rates on fecundity and egg size in years 1989 (overexploited fishery), 2004 (recovering fishery), and 2017 (recovered fishery), we analyzed linear models that related fecundity or egg size to morphological features for these three sampling periods. Walleyes were …

Goldeye Hidon Alosoides Calorimetry In Red Lake, Jesse Mendel

Journal of Earth and Life Science

Goldeye Hiodon alosoides are found across North America and are a relatively unstudied group of fish as they have had no economic value in the past. Ecologically speaking, these fish could have importance to the waters that they inhabit, as they are prey to fishes like Walleyes Sander vitreus, Northern Pike Esox lucius, and Muskellunge Esox masquinongy. These fish could potentially be vital to predatory fishes because of the amount of oil found in these fish, creating gram for gram more energy than compared to other consumable substances. The average energy density for all Goldeye was 6.73 …

Examining Black Bullhead Ameiurus Melas Age And Growth In Shallow Minnesota Lakes, Michael S. Collins, Anna M. Medina

Journal of Earth and Life Science

Ageing methods, population age structures, and growth trajectories for Black Bullhead Ameiurus melas were evaluated for six populations from shallow lakes divided between two ecoregions in Minnesota, USA. A total of 693 fish were collected in July and August 2018 and measured for total lengths (TL) and weights (g). We collected ageing structures from 320 of these fish. Crosssections of lapillar otoliths (n=191) and pectoral spine structures (n=75) were used to estimate age by two readers in a blind reading procedure. Fish caught ranged in total lengths from ~40 to 350 mm and weighed between 8 and 380 g. Black …

Effects Of Acute Hypoxia On Danio Rerio, Karly Crail

Williams Honors College, Honors Research Projects

The purpose of this research experiment was to determine the effects of acute hypoxia on the embryonic zebrafish (Danio rerio) cardiovascular system and assess the critical oxygen level at which embryonic function is compromised. This goal was achieved by exposing embryos to decreasing oxygen concentrations, (6.0 mg/L-0 mg/L) and observing the heart under an inverted microscope. Data analysis was conducted to determine end systolic volume, end diastolic volume, stroke volume, heart rate, and cardiac output. It was hypothesized that hypoxia would stimulate cardiac activity, because in early developmental stages, tissues are supplied with oxygen through bulk diffusion, and …

Suction Dredge Mining Impacts On Pacific Lamprey Populations And Habitat In Washington State: A Case Study Of The Entiat River, Jaime Liljegren

All Master's Theses

Suction dredge mining is a largely unregulated recreational activity in Washington State with potentially significant impacts to aquatic habitat. Although dredging has the potential to cause widespread ecological effects, only impacts to select species have been thoroughly assessed. Due to their reliance on freshwater habitat throughout multiple life stages, Pacific lamprey are significantly vulnerable to impacts from dredging practices. This thesis focuses on assessing the effects of dredging to lamprey habitat within state-owned aquatic lands of Washington. Pacific lamprey are anadromous, utilizing freshwater habitat throughout key life stages including spawning in substrate ranging from coarse gravel to fine sand, and …

Behavioral Insights Into Nociceptor Function: A Systematic Approach To Understanding Postsurgical And Neuropathic Pain Mechanisms In Rats, Max Odem

Dissertations and Theses (Open Access)

Postsurgical and neuropathic pain are each clinically common, and often associated with ongoing pain. Ongoing pain has been linked to ongoing activity (OA) in human C-fiber nociceptors. Preclinical studies using rodent neuropathic models have concentrated on allodynia driven by OA generated in non-nociceptive Aβ fibers, but little attention has been paid to postsurgical pain in sham controls or to C-fiber nociceptor OA promoting ongoing pain.

Operant assays that reveal negative motivational and cognitive aspects of voluntary pain-related behavior may be particularly sensitive to pain-related alterations. In the mechanical conflict (MC) test, rodents can freely choose to escape from a brightly …

Adult Walleye Abundance And Subsequent Fry Production In The Tamarac River, Mn, Phillip Oswald

Biology Graduate Theses

Walleye reproductive success is of critical interest for the Red Lakes as this system is maintained entirely by natural reproduction and supports robust commercial and recreational fisheries. The Tamarac River, a major tributary to the Red Lakes, hosts a substantial Walleye spawning migration annually. The river drains the largest peat bog in the lower 48 states and thus experiences low dissolved oxygen at times. It is largely unknown how the potential anoxic bog water affects Walleye reproductive success each year and subsequent year class strength. Fyke nets were set from 2014-2018 to assess the relative abundance of adult Walleye spawning …

Growth Of Pelagic Age-0 Yellow Perch In Relation To Hatch Dates And Water Temperature In North-Central Minnesota Lakes, Ethan Karppinen

Biology Graduate Theses

Exposure to consistent water warming rates and access to abundant populations of edible sized zooplankton affects growth and increases the probability of survival for newly hatched Yellow Perch Perca flavescens. Seven lakes with varying physical characteristics were selected in north-central Minnesota to study abiotic (water temperature) and biotic (zooplankton community and fish growth) progressions during the spring and early summer (April-June). Mean water temperatures from ice-out to 28 June (11.98-14.62 °C) had significant relationships with mean depth (P < 0.01, R? = 0.85), max depth (P < 0.01, R? = 0.73), and total volume (P < 0.01, R2 = 0.54). Hatch periods ranged from 13 to 19 days in 2015 and 13 to 25 days in 2016. Cumulative degree-days (CDD) were used to predict Yellow Perch hatch periods and explain growth. CDD predicted 21-81% of hatch periods in 2015 and 11-50% in 2016. Mean predicted total lengths at 28 June were 19.65-30.41 mm in 2015 and 20.88-28.54 mm in 2016. There was a significant relationship between CDD and predicted total length (R? = 0.62, P < 0.01) to explain differences in Yellow Perch total length while inhabiting the pelagic zone. Observed gape measurements were highly correlated with predicted gapes from the Schael formula (R? = 0.89, P < 0.01) that was used to assess the availability of edible sized zooplankton for age-0 Yellow Perch in each lake. No predator-prey mismatches were found and earlier hatch dates produced age-0 Yellow Perch with greater predicted total lengths in late June on the majority of lakes. This suggests that earlier hatched Yellow perch have an advantage over later hatched Yellow Perch in attaining greater lengths by late June. Our study provides information on a variety of physical and biological progressions in lakes, which may be used for fisheries management practices in the future.

Population Characteristics Of A Closed Northern Pike (Esox Lucius) Catch-And-Release Population In Minnesota, John Kempe

Biology Graduate Theses

Literature regarding catch-and-release populations of Northern Pike are rare and provide a unique perspective on their population dynamics. Shingobee Lake is a 64- ha mesotrophic lake with a maximum depth of 12.2 m located in northern Minnesota. Northern Pike fishing has been catch-and-release only since 2005, and there are no public accesses on the lake. Annual ice-out trap-netting occurred from 2009-2017, and a sizable amount of the Northern Pike recaptured via trapnet or angling had been previously tagged (37-59%). The lack of exploitation and high tagging percentage provided a unique opportunity to study the population dynamics of Northern Pike. Shinogbee’s …

Growth Rate And Hatch Date Of Age-0 Fishes On Leech Lake, Minnesota Before Zebra Mussel Establishment, Kayla Morey, Emily Larson

Journal of Earth and Life Science

The introduction of an invasive species to an ecosystem is considered a very severe environmental problem. Zebra Mussel veligers Dreissena polymorpha have recently been found in Leech Lake, Minnesota, and are likely going to have a large influence on this ecosystem. Zebra Mussels are filter-feeders that rely on phytoplankton and zooplankton as their main source of energy. A shift in populations of plankton due to Zebra Mussels may affect the growth rates of larval fish. Median hatch dates and growth rates were estimated from four age-0 fish species (Yellow Perch Perca flavescens, Walleye Sander vitreus, Smallmouth Bass Micropterus …

Seasonal Fluctuations Of Zooplankton, Dissolved Oxygen, And Temperature In Lake Bemidji, Minnesota, Cody Coyle

Journal of Earth and Life Science

With the current influx of aquatic invasive species in Minnesota lakes, the status of zooplankton has become vital. Zooplankton are at the base of all food chains in aquatic ecosystems, ecosystems that vary greatly throughout a year’s time. The objectives of this study were to 1) track the location of zooplankton throughout the water column for an entire year, and 2) establish relationships between zooplankton location and specific water column characteristics. Zooplankton, dissolved oxygen, and temperature samples were collected bi-monthly at various depths at the deepest point in the southern basin of Lake Bemidji. Zooplankton were most abundant in the …

Age-0 Walleye Growth Rates Following Spiny Water Flea Bythotrephes Longimanus Invasion, Joseph Amundson

Journal of Earth and Life Science

Within Voyageurs National Park, spiny water flea Bythotrephes longimanus has reduced Lake Kabetogama and Rainy Lake native zooplankton biomass during summer peak by 40-60%. Subsequently, planktivorous age-0 Yellow Perch Perca flavescens growth has decreased. A possible trophic cascade may influence predatory fish growth rates like that of age-0 Walleye Sander vitreus. Using seine net and electrofishing data, age-0 Walleye growth rates were modeled as a linear function of growing degree days (GDD) and the slope was compared between pre- and post-spiny water flea establishment. Nearby Lake Vermilion, assumed to have been unaffected by spiny water flea until 2015 and …

Burbot Activity In Relation To Light Penetration On Lake Bemidji, Mn, Hunter Weidenborner, Josh Janecek

Journal of Earth and Life Science

Burbot Lota lota is the only freshwater member of the family Gadidae and has a circumpolar distribution in cold-water regions. Information related to Burbot biology is limited in comparison to most fishes. Snow pack depth and ice conditions influence light penetration and therefore primary production levels. Primary production can have cascading effects on higher trophic levels. Therefore, the objective of this study was to observe if light levels penetrating through cleared and covered ice has an effect on Burbot activity in Lake Bemidji, MN. Angling for Burbot occurred for a minimum of 30 four hour sample periods at both cleared …

Hunter Harvest Effect On The Breeding Bird Population Of Northern Pintail Anas Acuta In North America, Matthew Wang

Journal of Earth and Life Science

Hunter harvest and the effects that it can have on population dynamics is a relationship used by wildlife professionals when making management decisions. Hunter harvest can be compensatory or additive on wildlife populations and instances where hunter harvest has been a key role in a population decline, and sometimes demise, is an occurrence studied in wildlife management. Waterfowl numbers in North America have increased 17% since 1960, but during that same time frame the Northern Pintail population has decreased 40%. Hunter harvest data has been recorded by the U.S. Fish and Wildlife Service since 1961, while they have simultaneously been …

Measured Soil Hydraulic Properties As Rzwqm2 Input To Simulate Soil Water Dynamics And Crop Evapotranspiration, Saadi Sattar Shahadha

Theses and Dissertations--Plant and Soil Sciences

Agricultural system models integrate many different processes that cannot all be measured in field experiments and help quantify soil water dynamics, crop evapotranspiration, and crop growth with high temporal resolution. Understanding soil water dynamics and crop evapotranspiration is essential to improve agricultural management of field crops. For example, the interaction between nitrogen application rate and water dynamics is not sufficiently understood. In most cases, model simulations deviate from field measurements, especially when model input parameters are indirectly and unspecifically derived. The extent to which measured soil hydraulic property inputs decrease the discrepancy between measured and simulated soil water status is …

Impact Of Temperature Increase On Freshwater Fish Species: Energetics And Muscle Mechanics Of Two Centrarchids, Israt Jahan

Masters Theses

Fishes have evolved physiologically to live within a specific range of environmental variation and existence outside of that range can be stressful or fatal. These ranges can coincide for fishes that evolved in similar habitats. This study investigates physiological processes limiting thermal tolerance, specifically how changes in water temperature affect the swimming energetics and muscle mechanics in largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus). I focused on the impact of temperature change at the muscle level in these two species and the capacity to adapt to rapid changes in the environment. Fish were housed at …

Modeling Canopy Effect In The Great Lakes Cladophora Model, Ankita Bakshi

Dissertations, Master's Theses and Master's Reports

Cladophora glomerata is a filamentous green alga native to the Great Lakes. However, its nuisance growth in phosphorus rich waters negatively affects the lakes’ aesthetic and water quality. The Great Lakes Cladophora Model (GLCM) v1, developed in 1982, was the first mechanistic model to simulate Cladophora growth basing phosphorus availability and environmental conditions followed by Cladophora Growth Model and GLCM v2. In this study, the light and temperature mediation factors for Cladophora net growth are revised as a necessary step prior to the development of a self-shading algorithm. The concept of a fixed-value, maximum achievable biomass (carrying capacity) employed in …

Immunology Of The Gray Short-Tailed Opossum During Pregnancy And Prenatal Development, Victoria L. Hansen

Biology ETDs

Vertebrate species that bear live young have overcome the evolutionary challenge of maintaining both a functional adaptive immune system and viviparous life cycle. In normal pregnancy, viviparous mothers are able sustain and nourish a fetus that is genetically half non-self without mounting an immunological attack. In 1953 Sir Peter Medawar brought attention to the “enigma of the fetal graft” and immunologists have been puzzling out the intricacies of fetal tolerance ever since. Although viviparity has evolved in all jawed vertebrate lineages aside from Aves, the vast majority of reproductive immunology research has been limited to eutherian mammals. There are insights …

Estimating Seasonal Variation In Condition Of Yellow Perch, Emily Anne Powers

Biology Graduate Theses

Research has shown that Yellow Perch Perca flavescens, found throughout lakes and streams of North America, are good indicators of environmental health. Due to the correlation between fish condition and ecosystem health it is essential to reliably estimate condition to better manage our fisheries. Therefore, the study objectives were to measure the seasonal changes in adult Yellow Perch percent dry weight (PDW), and compare the reliability of bioelectrical impedance analysis (BIA) and morphometric-based estimates of condition. The seasonal fluctuations in average monthly PDW were measured over a two- year period and were sinusoidal in shape with peaks in August 2015 …

Relationship Between Zooplankton And Walleye Rearing Pond Success, Danny Tuckett

Journal of Earth and Life Science

Walleye Sander vitreus are an important sport fish in Minnesota. This has led to the raising of Walleye in ponds to later be stocked into lakes. This study was done to determine the relationship between Walleye prey (zooplankton) and the success of Walleye in 11 stocked ponds in the Ortonville, MN area. There was no management of the ponds until harvest, which starts in late September and ends in November. There were significant positive relationships between rotifer density (P = 0.03) and nauplii density (P = 0.04) to kg of Walleye harvested. The setting where nauplii and rotifer density are …

Redd Habitat Selection For Brook Trout In The Necktie River Bemidji, Mn, William Varela, Zachary Buckley

Journal of Earth and Life Science

The presence of quality suitable habitat is important for the success of naturally reproducing Brook Trout populations. Therefore, measuring redd habitat Brook Trout select for was the focus of this study. Brook Trout redds were observed during the spawning season of 2016. We identified a total of 18 redds in the Necktie River in late October and early November. Specific environmental variables associated with redd selection were measured: velocity, in-stream cover, canopy cover, bank overhang, river width, substrate type and size, temperature, and max-depth. The same environmental variables were measured for 30 randomly selected sites. Redds were distributed in riffles …

Influence Of Time Spent In Captivity On Aggressive Behaviors Of Gray Wolves Canis Lupus, Chelsea Knutson

Journal of Earth and Life Science

Knowledge of the characteristics that promote group success is key to understanding the adaptive advantages of sociality for many group-oriented species. In this study, nine Gray Wolves Canis lupis were each observed twelve times over a period of six months to determine if the amount of time spent in the wild/captivity had any effect on aggressive behaviors. The number of aggressive behaviors were recorded for each wolf during each observation. The nine wolves were separated into three groups depending on their upbringing; born and raised in captivity, born in the wild and raised in captivity, and born and raised in …