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Articles 61 - 90 of 97
Full-Text Articles in Terrestrial and Aquatic Ecology
Goldeye Hidon Alosoides Calorimetry In Red Lake, Jesse Mendel
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
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 …
Growth Of Pelagic Age-0 Yellow Perch In Relation To Hatch Dates And Water Temperature In North-Central Minnesota Lakes, Ethan Karppinen
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
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
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 …
Age-0 Walleye Growth Rates Following Spiny Water Flea Bythotrephes Longimanus Invasion, Joseph Amundson
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
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 …
Estimating Seasonal Variation In Condition Of Yellow Perch, Emily Anne Powers
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
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
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 …
Burbot Growth Rates In A Northern Mesotrophic Lake, Samuel J. Peterson
Burbot Growth Rates In A Northern Mesotrophic Lake, Samuel J. Peterson
Journal of Earth and Life Science
Burbot Lota lota has a circumpolar distribution throughout cold-water areas and is the only freshwater member of the family Gadidae. There are currently very few management techniques applied to Burbot throughout their northern extent. Growth is an indicator of fish health, biomass, and habitat quality; therefore, the objective of this study was to determine the growth rate of Burbot in Lake Bemidji. Burbot (n = 45) were collected along three sites on Lake Bemidji for years 2015-2017. Age was determined from sagittal otoliths, the marginal zones of which were opaque from December to May and translucent from June to November. …
Effects Of Catch-And-Release Angling On Egg Densities In Largemouth Bass Nests, Tyler Robinson
Effects Of Catch-And-Release Angling On Egg Densities In Largemouth Bass Nests, Tyler Robinson
Journal of Earth and Life Science
Predation during early life stages of Centrarchidae offspring are a major cause of decreased reproductive success. For five-weeks Largemouth Bass Micropterus salmoides defend their broods from invaders such as Yellow Perch Perca flavescens and Bluegill Lepomis macrochirus. The focus of this study was to determine if predation upon Largemouth Bass broods increased as removal time from the nest via catch-and-release angling increased. Sampling was conducted on the Whitefish Chain, MN from 7 May - 7 June 2016, where a total of 29 nests were located and sampled. Three treatment groups were used; immediate catch-and-release, three-minute, and a seven- minute …
Effect Of Abiotic Factors On Bluegill Size Structure In Nine Central Minnesota Lakes, Ryan Henry
Effect Of Abiotic Factors On Bluegill Size Structure In Nine Central Minnesota Lakes, Ryan Henry
Journal of Earth and Life Science
Bluegill are the most targeted species of fish in Minnesota. In recent years, the abundance of slow growing, small Bluegill has increased within the state. Angler harvest of Bluegill can reduce the average length of Bluegill up to four times the original length. Abiotic factors such as maximum depth, average water clarity, littoral area, and percent littoral area can influence the dynamics of a lake system. There has been limited research on whether these abiotic factors can influence the size structure of a Bluegill population. The objective of this study is to determine if there is a direct relationship between …
Assessment Of American White Pelican Predation And Reproductive Success Of Walleye In The Tamarac River, Mn, Jake Graham
Assessment Of American White Pelican Predation And Reproductive Success Of Walleye In The Tamarac River, Mn, Jake Graham
Biology Graduate Theses
The Tamarac River is a major tributary of the Red Lakes MN, which provides an economically important multispecies fishery. The river experiences spring spawning migrations of northern pike, walleye, and white suckers. However, limited data exists related to reproductive success of fishes in the river. Furthermore, in the previous decade large congregations of American white pelicans (AWPE) have been observed using the Tamarac River as a foraging ground each spring. Assessing reproductive success of fishes in the Tamarac River provides a more holistic understanding of fish ecology in the river and the importance of the Tamarac River to the Red …
Survival Of Walleye Eggs In Upper Red Lake And The Tamarac River, Phillip Oswald
Survival Of Walleye Eggs In Upper Red Lake And The Tamarac River, Phillip Oswald
Journal of Earth and Life Science
Walleyes experience spawning runs each spring in the Tamarac River, a tributary of the Red Lakes. However, data about walleye egg survival in the lake and river is lacking. Mesh cages were placed in both the Tamarac River and Upper Red Lake to compare survival rates. A total of twenty cages were set, ten in the river and ten in the lake. Each cage contained one hundred fertilized eggs which were checked every third day to measure survival. Temperature (°C), dissolved oxygen (mg/L), and pH were measured at each cage location. The river had an average survival rate of 22% …
Abiotic Habitat Preferences Of Age-0 Paddlefish In Lake Sakakawea, North Dakota During Late Summer, Derek Dufault
Abiotic Habitat Preferences Of Age-0 Paddlefish In Lake Sakakawea, North Dakota During Late Summer, Derek Dufault
Journal of Earth and Life Science
Since the early 1990’s, surface visual counts along transects have been conducted annually, allowing for estimates of relative abundance and year-class strength of age-0 paddlefish Polyodon spathula on the upper portions of Lake Sakakawea, North Dakota. This study focuses on the annual visual surface count data collected over an eleven year period from 2004-2014. More specifically it focuses on abiotic habitat factors (Secchi depth, water depth, and water temperature) and how they relate to age-0 paddlefish locations in late summer. Understanding habitat use during early life stages is imperative, yet to date, there is very limited knowledge available regarding the …
Influence Of Depth And Retrieval Speed On Yellow Perch Barotrauma Recovery Time In Winter, Bradley J. Klingsheim
Influence Of Depth And Retrieval Speed On Yellow Perch Barotrauma Recovery Time In Winter, Bradley J. Klingsheim
Journal of Earth and Life Science
Physoclistous fish are often affected by barotrauma because the swim bladder is not connected to the esophagus. Barotrauma is increasingly being used in assessing mortality in fish brought from deep water. Barotrauma is the physical damage that occurs because of the over inflation of the gas bladder resulting from a rapid decrease in ambient pressure. The two important factors influencing barotrauma effects are water depth and decompression. In this study, two experiments were conducted on yellow perch (Perca flavescens) at three depth locations on Grace Lake, Bemidji, Minnesota. Fish were measured for barotrauma recovery time (s) following capture by hook …
Assessing The Contributions Of Two Stocked Strains On A Minnesota-Wisconsin Border Water, Douglas Zentner
Assessing The Contributions Of Two Stocked Strains On A Minnesota-Wisconsin Border Water, Douglas Zentner
Journal of Earth and Life Science
Stocking has long been used as a management tool in the United States even though many of its effects remain cryptic. Past comparisons between stocked strains were generally based on the survival and growth rates of physically marked individuals. More recently the use of genetic markers to assess contributions of stocked individuals has been employed by fisheries managers. Using 13 microsatellite markers we assessed the contributions of two muskellunge (Esox masquinongy) strains (Wisconsin and Leech) stocked into the St. Louis River Estuary. Ancestry in the adult samples remained relatively constant with differences only observed between the 2008 and …
Using Wild I.D. As A Reliable Source For Mark And Recapture Studies On Northern Pike (Esox Lucius), Martin Evans
Using Wild I.D. As A Reliable Source For Mark And Recapture Studies On Northern Pike (Esox Lucius), Martin Evans
Journal of Earth and Life Science
Mark and recapture studies are a very popular method fisheries biologists use to assess certain fish populations in lakes. This process can be very labor intensive and expensive. Wild I.D. is free software developed by Dartmouth College that uses SIFT program to find unique features in photographs. Initially developed for identification of African land mammals the program gives each photo a score and percent match to other photos. Northern pike were used in this study to determine if the program can recognize simulated recapture events. Photos of sample fish were taken at two separate locations, the photos were then copied …
Juvenile Chinook Salmon Diet In Comparison To Invertebrate Drift In The Merced River, California, Tyler Orgon
Juvenile Chinook Salmon Diet In Comparison To Invertebrate Drift In The Merced River, California, Tyler Orgon
Journal of Earth and Life Science
Diets and habitat types of salmonids have been widely studied in disturbed streams and rivers. The Merced River in California has a long history of flooding, damming, levee failures, and channel reconstruction events that has disrupted the aquatic ecosystem. This 30 day study was conducted in the Robinson Reach of the Merced River using juvenile Chinook salmon (Oncorhynchus tshawtscha). The objectives were to try and understand if juvenile Chinook salmon were selecting certain invertebrate species, determine if there were any differences in diets between habitat types, and determine whether diets and drift samples were different. Diets consisted of …
Effects Of Cooler Northern Waters On Growth Rates In Bluegill And Pumpkinseed Sunfish, Alec Spurbeck
Effects Of Cooler Northern Waters On Growth Rates In Bluegill And Pumpkinseed Sunfish, Alec Spurbeck
Journal of Earth and Life Science
The Centrarchidae family range spans all across the United States making them a favorite target for many recreational anglers. In northern Minnesota, most water bodies do not reach optimal growth temperatures for the sunfishes, putting them right on the edge of their suitable range and potentially slowing overall growth. Therefore, the main objectives of this study were to 1) determine if sunfish growth rates respond to the severity of winter and 2) investigate growth differences between two sunfish species. Growth rates of bluegill (Lepomis macrochirus) and pumpkinseed (Lepomis gibbosus) were estimated from Big Sugar Bush Lake, …
Spatial And Temporal Factors Influencing Northern Pike Fry Density Estimates, Nate Stott
Spatial And Temporal Factors Influencing Northern Pike Fry Density Estimates, Nate Stott
Journal of Earth and Life Science
The Tamarac River in northern Minnesota is an important spawning site for northern pike (Esox lucius) in the Red Lake system. However, little is known about fry production in the river. This study investigates migration densities and spatial and temporal factors influencing northern pike fry density estimates. Northern pike fry were collected with drift nets between 28 May and 4 June 2014. Thirty northern pike fry were randomly selected to have total length measured from each sample. Northern pike fry were observed in the first sample day. Northern pike fry density maxima occurred on 29 May at midnight …
A Genetic Based Approach To Management And Stocking Of Muskellunge, Douglas Zentner
A Genetic Based Approach To Management And Stocking Of Muskellunge, Douglas Zentner
Journal of Earth and Life Science
Fish stocking has long been used as a management tool among fisheries biologists and continues to be met with popular public opinion. Despite perceived simplicity, the full effects of stocking remain cryptic for many fish populations. Stocking has frequently been used to maintain or establish successful muskellunge (Esox masquinongy) populations. Coupled with other management practices the Minnesota Department of Natural Resources (MNDNR) has established Minnesota as a premier muskellunge fishery. From 1958 to 2012 the MNDNR stocked three strains of muskellunge in Big Mantrap Lake, MN. The first from Shoepack Lake, MN (hereafter Shoepack-strain) was used until the …
Effects Of River Current Inflow On Dissolved Oxygen And Temperature Of Refuge Zones For Cisco In Lake Bemidji, Bryant C. Swenson
Effects Of River Current Inflow On Dissolved Oxygen And Temperature Of Refuge Zones For Cisco In Lake Bemidji, Bryant C. Swenson
Journal of Earth and Life Science
The objectives of this study were to (1) determine if the inflow current from the Mississippi River affects temperature and dissolved oxygen in Lake Bemidji, (2) determine how the amount of suitable cisco Coregonus artedi habitat changes over the summer in Lake Bemidji, and (3) predict how much cisco habitat would be available under a climate warming scenario. Summer fish kill of cisco occurs in most years on Lake Bemidji resulting from low dissolved oxygen in the hypolimnion and high water temperatures in the epilimnion. Dissolved oxygen and temperature profiles provided evidence to suggest the north basin is more suitable …
The Effect Of Barometric Pressure On Feeding Activity Of Yellow Perch, Daniel Vanderweyst
The Effect Of Barometric Pressure On Feeding Activity Of Yellow Perch, Daniel Vanderweyst
Journal of Earth and Life Science
This is the first study to our knowledge that has attempted to relate feeding activity of fish to barometric pressure. This study was conducted with the expectation that a difference in food ingestion would occur in a game fish species at different barometric pressures. The overall objective of this study is to determine if barometric pressure influences the feeding activity of a popular game fish. Yellow perch (Perca flavescens) were collected by seine and trap net from Lake Bemidji 12 September through 24 October 2013. The range in size and weight of yellow perch used for this study …
Use Of Cast Nets And Seine Hauls To Estimate Abundance Of Age-0 Yellow Perch, Michael Vaske
Use Of Cast Nets And Seine Hauls To Estimate Abundance Of Age-0 Yellow Perch, Michael Vaske
Journal of Earth and Life Science
Knowledge about fish population dynamics is essential for developing management plans and evaluating management success. In many lakes, yellow perch (Perca flavescens) are the main forage for many upper level predators and recreational fish species. To better manage recreational fisheries, an accurate estimate of prey abundance is necessary. The objectives of the study were to sample the littoral and limnetic zone to better estimate population of age-0 yellow perch, and obtain an estimate of the proportion of yellow perch being missed by traditional littoral seining methods. Littoral seines were conducted at three randomly selected locations in the south …
Changing Body Condition In Walleye With Reference To Ideal Sample Size Requirements, Kevin Longtin
Changing Body Condition In Walleye With Reference To Ideal Sample Size Requirements, Kevin Longtin
Journal of Earth and Life Science
The objective of this study was to determine if walleye Sander vitreus percent dry weight, a measure of condition, differed among summer months of 2014 on Maple Lake, Minnesota. A second objective was to determine if there was a relationship between condition and body temperature, total length, or wet weight. Between three and six walleyes were collected per month by hook and line methods. All fish had internal body temperatures taken at the time of capture and were oven dried in the laboratory at 80 °C in order to measure percent dry weight. There was no relationship between condition and …
Defining The Physiochemical, Biological And Habitat Requirements For The Upper Extant Of Oncorhynchus Mykiss Distribution, Emily Powers
Defining The Physiochemical, Biological And Habitat Requirements For The Upper Extant Of Oncorhynchus Mykiss Distribution, Emily Powers
Journal of Earth and Life Science
The distribution of rainbow trout is strongly influenced by their habitat. As climatic conditions change, the distribution of rainbow trout populations will change along with them. The objective of this study was to identify the particular habitat parameters that rainbow trout select for in this lotic system and to specifically assess how this relates to the upper extant of their distribution. By assessing the distribution of the upper extant specifically, future research may be conducted to better assess climatic changes on a small and/or large scale basis. A 9,000 m section of the Clearwater River was used as the study …
The Effects Of Angling Pressure On Northern Pike Size Structure, Ryan Carrow
The Effects Of Angling Pressure On Northern Pike Size Structure, Ryan Carrow
Journal of Earth and Life Science
A number of conditions within a lake system can affect northern pike (Esox lucius) size structure. Of these conditions, the amount of angling pressure may have the biggest effect on the size structure of northern pike in Minnesota lake systems. In this study, five private and five public lakes were chosen near Bemidji, Minnesota. Each lake was fished for twenty angling hours using live northern hog suckers (Hypentelium nigricans) or golden shiners (Notemigonus crysoleucas). Total length (mm) and weight (kg) were measured for each northern pike caught. The number of fish houses that were …
Winter Survival Strategies Of Benthic Invertebrates In Temporary Habitats In A Northern Minnesota Lake, Cal Oldenburg
Winter Survival Strategies Of Benthic Invertebrates In Temporary Habitats In A Northern Minnesota Lake, Cal Oldenburg
Journal of Earth and Life Science
During the winter months in the northern hemisphere, above 40 degrees latitude, a freezing event occurs that can last several months. Some lakes may have large portions of the shallow littoral zone frozen completely solid down into the sediments. Invertebrates affected by these events have developed survival strategies to cope with the harsh environment. The two main strategies for invertebrates in these areas are to either migrate to a different area and recolonize the original area when it becomes available again, or to burrow into the sediments and withstand the freezing. A 1- month study took place on Lake Bemidji …