Aquaculture and Fisheries Commons^™

Environmental Effects On Biomass Allocation And Small Plot Evaluations Of Aquatic Pesticides For Control Of Nitellopsis Obtusa (Starry Stonewort) Collected From Lake Koronis In Stearns County, Minnesota, Patrick J. Carver

All Graduate Theses, Dissertations, and Other Capstone Projects

Phenology is the study of critical life stages in plants in relation to shifts in environmental factors during seasonal changes. Starry stonewort is a green macro alga in the family Characeae native to Eurasia. Much of the Midwestern United States has been invaded by this species. Starry stonewort has been seen to have late season growth patterns in its invaded range. This study found that this growth pattern was dependent upon water temperature and light transmittance both of which affect biomass production and senescence. It was hypothesized that peak biomass would occur in the late summer (August), however we observed …

Effects Of Hydrology On The Growth And Recruitment Of Stream Fish In The Eastern Broadleaf Province Of Minnesota, Eric J. Krumm

All Graduate Theses, Dissertations, and Other Capstone Projects

Agricultural practices and urban development have altered streamflows within the Eastern Broadleaf Province of Minnesota. Stream-flow alteration can produce significant changes in native freshwater communities. Therefore, knowledge of streamflow effects on representative freshwater populations and communities within the province are needed to maintain ecological integrity. Fish community and population dynamics often display predictable responses to flow regimes, which can make fishes model organisms for examining flow-ecology relationships.

In lotic systems, annual variation in streamflow can influence the annual growth and recruitment of fishes. Understanding the growth and recruitment of fish populations is essential for management and conservation efforts. Growth can …

Zooplanktonic Community Dynamics Of The Minnesota River With An Ichthyoplankton Gear Comparison, Nathaniel Lederman

All Graduate Theses, Dissertations, and Other Capstone Projects

The Minnesota River, like many large rivers, has been functionally altered by human activities and climate change. The Minnesota Pollution Control Agency has designated 271 kilometers (50.3%) of the 539 kilometer Minnesota River as “biologically impaired.” However, assessing biological communities in large rivers is often difficult and limited to examination of upper trophic levels (e.g., piscivorous fishes). Few studies examined zooplanktonic communities, largely due to difficulties associated with sampling. Because of the need to improve assessment strategies for biological impairments in the Minnesota River, the zooplanktonic community, including crustaceous zooplankton, rotifers, macroinvertebrates, and ichthyoplankton was evaluated within an impaired and …

Hydrologic And Temperature Regime Influence On Growth And Recruitment Of Fishes In An Upper Midwest Riverine Ecosystem, Brett Donald Nelson

All Graduate Theses, Dissertations, and Other Capstone Projects

The natural flow regime is often identified as the primary driver of ecological integrity in rivers. The Minnesota River basin is characterized by a row-crop agricultural landscape with an extensive network of drainage tiles and ditches to improve land productivity. Intensive surface and subsurface drainage alters flow regimes, increasing the magnitude and frequency of high flows. Changes in river hydrology lead to alterations in geomorphology, including increased bank erosion, channel widening, and downward incision that can lead to floodplain disconnection. Disruption of historical hydrology can alter energy flow and connection to specialized habitats subsequently affecting important aquatic communities and populations …

Zebra Mussel (Dreissena Polymorpha) Habitat Associations In Four West-Central Minnesota Lakes, April Rose Londo

All Graduate Theses, Dissertations, and Other Capstone Projects

In 1989, zebra mussels (Dreissena polymorpha) were first documented in the land of ten thousand lakes in the Lake Superior Basin at Duluth. Zebra mussels are successful invaders because the species attaches to substrates with byssal threads, can adapt to a wide range of environmental conditions, and has a free-swimming veligers that are easily transported. Although invasive mollusks pose a range of economic and ecological threats to inland waters, our understanding of zebra mussels in Minnesota lakes remains limited. To gain additional information regarding zebra mussel ecology in lake systems, I conducted research in four west-central Minnesota lakes that were …

Effect Of Increased Water Temperature On Warm Water Fish Feeding Behavior And Habitat Use, Eric Walberg

Journal of Undergraduate Research at Minnesota State University, Mankato

Global warming could cause changes in species behavior and life history. Stream fish may be significantly affected by climate change because individuals are restricted in their movements by water systems and other physical factors, preventing migration to locations more thermally suitable. The effect of warmer waters on stream fish could change behavior and affect the fish species survival and ultimately ecosystem function. During my experiment I observed the effects of increased water temperature on the feeding behavior and habitat use of two native Minnesota fish species, black crappie (Pomoxis nigromaculatus) and black bullhead (Ameiurus melas). An increase of 2oC over …

Anti-Predator Responses Of Fathead Minnows To Alarm Substance Pheromone, Sarah Thomson

Journal of Undergraduate Research at Minnesota State University, Mankato

In some fish, alarm substances are released from skin cells when they are bitten by a predator, signaling nearby fish in potential danger. Such anti-predator defenses have been studied in the fathead minnow (Pimephales promelas), and some have hypothesized that the response to the alarm substance is not instinctual, but rather fish must learn to associate it with a predation cue such as motion. The purpose of this study is to detect an effect of conditioning (associating alarm substance with predation threat) on minnow responses to alarm substance. We tested the prediction that conditioned fish would react more strongly to …

Atrazine Influence On Northern Pike Sperm Motility And Viability In Minnesota, Andy Stevens, Paul Pallardy

Journal of Undergraduate Research at Minnesota State University, Mankato

Concern has been noted by fish hatchery biologists with the Department of Natural Resources that southern Minnesota northern pike Esox lucius populations have exhibited reduced hatching rates, a trend not occurring with northern Minnesota pike populations. The chemical atrazine is a frequently used herbicide in Minnesota and has been found to cause gonadal dysgenesis and reproductive development issues in amphibians and fish. Sperm, length, and age data were collected from northern pike in four Minnesota lakes. Water samples were obtained from two of the lakes to test for atrazine. Test results indicated atrazine concentrations0.10 and r2 < 0.06 for all regressions). Sperm motility reductions in northern pike could be related to declining populations and warrants further research.

Estrogenic Effects On A Protandrous Hermaphroditic Species: Amphiprion Percula, Randall Burns, Katie Dose

Undergraduate Research Symposium

Estrogen concentrations are increased in aquatic environments due to the addition of pharmaceutical drugs (i.e. birth control) through runoff water. This manipulates maturation of sexes within many species that inhabit aquatic enviornments, including fresh and marine habitats. Amphiprion percula exhibit a hierarchal system behavioral pattern, which determines the social status of individuals within a group. Multiple clown anemonefish, A. percula were studied via a controlled environment and hierarchal succession was observed under estrogenic additions. From this study, data on sex change of a hermaphroditic protandrous species was observed under the influence of three concentrations of natural estrogen. Based on sex …

Dolphin-Assisted Therapy: Claims Versus Evidence, Britta L. Fiksdal, Daniel Houlihan, Aaron C. Barnes

Psychology Department Publications

The purpose of this paper is to review and critique studies that have been conducted on dolphin-assisted therapy for children with various disorders. Studies have been released claiming swimming with dolphins is therapeutic and beneficial for children with autism, attention deficit hyperactivity disorder, physical disabilities, and other psychological disorders. The majority of the studies conducted supporting the effectiveness of dolphin-assisted therapy have been found to have major methodological concerns making it impossible to draw valid conclusions. Readers will be informed of the history of, theory behind, and variations of dolphin-assisted therapy along with a review and critique of studies published …