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Articles 91 - 120 of 420

Full-Text Articles in Population Biology

Population Demographics Of Silver Carp Hypophthalmichthys Molitrix In Kentucky Lake, Allison M. Lebeda Jan 2020

Population Demographics Of Silver Carp Hypophthalmichthys Molitrix In Kentucky Lake, Allison M. Lebeda

Murray State Theses and Dissertations

Invasive species continue to threaten aquatic ecosystems in the United States. Silver Carp Hypophthalmichthys molitrix have successfully infiltrated much of the Mississippi River Basin, including Kentucky Lake – a large reservoir located on the Tennessee River in Western Kentucky. Although Silver Carp have been present in Kentucky Lake for at least a decade, until recently, very little was known about the population, how often successful reproduction is occurring, or the environmental conditions that facilitate strong year-classes. Hence, it is difficult for managers to predict the potential impact of Silver Carp on native species. Silver Carp were collected from Kentucky Lake …

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Habitat Associations And Reproduction Of Fishes On The Northwestern Gulf Of Mexico Shelf Edge, Elizabeth Marie Keller Nov 2019

Habitat Associations And Reproduction Of Fishes On The Northwestern Gulf Of Mexico Shelf Edge, Elizabeth Marie Keller

LSU Doctoral Dissertations

Several of the northwestern Gulf of Mexico (GOM) shelf-edge banks provide critical hard bottom habitat for coral and fish communities, supporting a wide diversity of ecologically and economically important species. These sites may be fish aggregation and spawning sites and provide important habitat for fish growth and reproduction. Already designated as habitat areas of particular concern, many of these banks are also under consideration for inclusion in the expansion of the Flower Garden Banks National Marine Sanctuary. This project aimed to gain a more comprehensive understanding of the communities and fish species on shelf-edge banks by way of gonad histology, …

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Effect Of Beaver On Brook Trout Habitat In North Shore, Lake Superior Streams, Kathryn Renik Aug 2019

Effect Of Beaver On Brook Trout Habitat In North Shore, Lake Superior Streams, Kathryn Renik

Biology Graduate Theses

In Minnesota, North American Beavers Castor canadensis (hereafter Beaver) are considered to have an overall negative affect on native Brook Trout Salvelinus fontinalis. Brook Trout provide a valued and productive sport fishery to the North Shore streams of Lake Superior and since revival of the Beaver population from past trapping and timber harvest, a reexamination of the complex ecological relationship where the two taxa interact is imperative. Suitable Brook Trout habitat is characterized by cold, spring- fed water with silt-free rocky substrate and abundant cover, all of which Beaver may directly, or indirectly, affect. Data collection occurred on 79 (200 …

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Stress And Body Composition Of Juvenile Alligator Snapping Turtles (Macrochelys Temminckii), Brandon Scott Tappmeyer May 2019

Stress And Body Composition Of Juvenile Alligator Snapping Turtles (Macrochelys Temminckii), Brandon Scott Tappmeyer

Graduate Theses/Dissertations

The alligator snapping turtle (Macrochelys temminckii), is a species of conservation concern that is the subject of multiple head-start and reintroduction efforts across its range. In captive propagation programs, producing offspring that are in optimal physiological condition maximizes the likelihood of success after release. The purpose of my study was to compare stress and body composition between one free-ranging reintroduced population and two captive populations. The two captive populations were both housed in southern Oklahoma, but one group was reared indoors whereas the other inhabited outdoor ponds at a national fish hatchery. I used circulating glucocorticoid (corticosterone) concentrations as an …

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Demersal Fish Use Of Printed Oyster Shells As Nesting Habitat In North Inlet Estuary, Sc, Annie Boyd, Juliana Harding May 2019

Demersal Fish Use Of Printed Oyster Shells As Nesting Habitat In North Inlet Estuary, Sc, Annie Boyd, Juliana Harding

Honors Theses

Temperate estuarine blenny species establish subtidal territories and nesting sites. Four blenny species co-occur in North Inlet, SC including the striped blenny, Chasmodes bosquianus, crested blenny, Hypleurochilus geminatus, feather blenny, Hypsoblennius hentzi, and freckled blenny, Hypsoblennius ionthas. All four fishes use empty oyster (Crassostrea virginica) shells as nesting sites. Current 3D printer technology was used to create standard nest substrates to describe relationships between blenny habitat use and nest site dimensions. Replicate printed shells of 2 gape widths (5, 7 mm) for each of 2 shell cavity volumes (22 mL, 15mL, Oyster A and …

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Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan May 2019

Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan

Masters Theses, 2010-2019

Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity “habitat squeeze” for populations of brook trout and could …

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Spatial And Temporal Variability In Post-Larval Yellow Perch Density, Steve Hauschildt Feb 2019

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 …

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Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert Jan 2019

Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert

University Faculty and Staff Publications

In response to our recent paper (Drymon et al. 2019), Yosef (2019) questions the mechanism proposed to explain interactions between tiger sharks (Galeocerdo cuvier) and migratory songbirds, while offering an alternative mechanism based on a single observation. We appreciate the comments from Yosef and the opportunity to respond.

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Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers Jan 2019

Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers

University Faculty and Staff Publications

No abstract provided.

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Effects Of Rainbow Trout On Brook Trout Population Size In Tributaries To Lake Superior In Cook County, Minnesota, Craig Tangren Jan 2019

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 …

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Examining Black Bullhead Ameiurus Melas Age And Growth In Shallow Minnesota Lakes, Michael S. Collins, Anna M. Medina Jan 2019

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 …

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Contribution Of Juvenile Estuarine Residency In A Bar-Built Estuary To Recruitment Of Chinook Salmon (Oncorhynchus Tshawytscha), Emily Katherine Chen Jan 2019

Contribution Of Juvenile Estuarine Residency In A Bar-Built Estuary To Recruitment Of Chinook Salmon (Oncorhynchus Tshawytscha), Emily Katherine Chen

Cal Poly Humboldt theses and projects

Estuaries are commonly touted as nurseries for out-migrating salmonids, providing higher prey availability than streams, a physiological transition zone, and refugee from marine predators. Yet the diversity of estuaries makes it difficult to generalize the effect they have on salmonid recruitment. In bar-built estuaries, sandbars form at the mouth of rivers during periods of low flow, closing access to the ocean and disrupting outmigration. In this thesis, I evaluated how residency in a bar-built estuary affects the growth, survival, and ultimately recruitment of Chinook salmon (Oncorhynchus tshawytscha) in Redwood Creek, California. I conducted a mark-recapture experiment on out-migrating …

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Legacy Habitat Suitability Of Eastern Oysters (Crassostrea Virginica) In Louisiana: A Prelude To Mississippi River Delta Freshwater Diversions, Tasia Mv Denapolis Dec 2018

Legacy Habitat Suitability Of Eastern Oysters (Crassostrea Virginica) In Louisiana: A Prelude To Mississippi River Delta Freshwater Diversions, Tasia Mv Denapolis

LSU New Orleans Theses and Dissertations

The Louisiana oyster industry is greatly impacted by freshwater and sediment diversions that are part of the effort to restore the state’s coastline. A habitat suitability index (HSI) proposes species-habitat relationships that can be instrumental in creating impact assessments and suitability predictions for management as new diversions are implemented. An oyster (Crassostrea virginica) HSI was developed using three variables crucial to oyster sustainability: average annual salinity, minimum monthly salinity, and average salinity during the spawning season. These Legacy HSI visualizations show annual fluctuations in the distribution of zones suitable for oyster cultivation prior to proposed diversions in Pontchartrain …

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An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn Oct 2018

An Evaluation Of Sciaenid Growth In The Gulf Of Mexico, Shane Flinn

LSU Master's Theses

Growth models estimate life history parameters that are used in the management of fisheries stocks. The most commonly used growth model in fisheries is the von Bertalanffy growth model (VBGM), yet it has been shown to provide a poor fit for length-at-age data of some species and other models exist. I reviewed 196 peer-reviewed age and growth studies and 50 NOAA stock assessments to examine temporal trends in the use of growth models and model selection in fisheries. I found that the use of multi-model frameworks has increased since the year 2000 and information theoretic approaches are replacing goodness-of-fit and …

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Protecting Breeding Stock Levels Of The Blue Swimmer Crab Resource In The South West : A Review Of Management Arrangements, Department Of Primary Industries And Regional Development Oct 2018

Protecting Breeding Stock Levels Of The Blue Swimmer Crab Resource In The South West : A Review Of Management Arrangements, Department Of Primary Industries And Regional Development

Fisheries Management Papers

This discussion paper identifies that the existing management arrangements do not adequately address the protection of the breeding stock across the resource because they have been developed at the scale of local estuaries and embayments. In particular, the arragements are not achieving appropriate levels of protection for mated, pre-spawned females, which become highly vulnerable to capture in late autumn, winter and spring.

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Short-Term Low Salinity Mitigates Effects Of Oil And Dispersant On Juvenile Eastern Oysters: A Laboratory Experiment With Implications For Oil Spill Response Activities, Meagan N. Schrandt, Sean Powers, F.Scott Rikard, Wilawan Thongda, Eric Peatman Sep 2018

Short-Term Low Salinity Mitigates Effects Of Oil And Dispersant On Juvenile Eastern Oysters: A Laboratory Experiment With Implications For Oil Spill Response Activities, Meagan N. Schrandt, Sean Powers, F.Scott Rikard, Wilawan Thongda, Eric Peatman

University Faculty and Staff Publications

Following the Deepwater Horizon oil spill, eastern oyster (Crassostrea virginica) reefs in the northern Gulf of Mexico were exposed to oil and various associated clean-up activities that may have compromised oyster reef health. Included in the exposure was oil, dispersant, and in some locales, atypical salinity regimes. Oil and dispersants can be detrimental to oysters and the effects of salinity depend on the level. In addition to these extrinsic factors, genetic diversity of oyster populations may help the oysters respond to stressors, as demonstrated in other systems. We used a 3×3×2 factorial design to experimentally examine the effects …

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Adult Walleye Abundance And Subsequent Fry Production In The Tamarac River, Mn, Phillip Oswald Sep 2018

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 …

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Growth Of Pelagic Age-0 Yellow Perch In Relation To Hatch Dates And Water Temperature In North-Central Minnesota Lakes, Ethan Karppinen Aug 2018

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.

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Pearl Oyster (Pinctada Maxima) Resource Allocation Report : Prepared By The Integrated Fisheries Allocation Advisory Committee, Department Of Fisheries Jun 2018

Pearl Oyster (Pinctada Maxima) Resource Allocation Report : Prepared By The Integrated Fisheries Allocation Advisory Committee, Department Of Fisheries

Fisheries Management Papers

No abstract provided.

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Western Australian Sea Cucumber Resource - Harvest Strategy 2018-2023, Department Of Primary Industries And Regional Development May 2018

Western Australian Sea Cucumber Resource - Harvest Strategy 2018-2023, Department Of Primary Industries And Regional Development

Fisheries Management Papers

This publication of harvest strategies is intended to make the decision-making considerations and processes for the management of specified aquatic resources publicly transparent and provide a basis for informed dialogue on management actions with resource users and other stakeholders.

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Population Characteristics Of A Closed Northern Pike (Esox Lucius) Catch-And-Release Population In Minnesota, John Kempe May 2018

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 …

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Gulls, Martin S. Lowney, Scott F. Beckerman, Scott C. Barras, Thomas W. Seamans May 2018

Gulls, Martin S. Lowney, Scott F. Beckerman, Scott C. Barras, Thomas W. Seamans

Wildlife Damage Management Technical Series

Abundant gull (Figure 1) populations in North America have led to a variety of conflicts with people. Gulls cause damage at aquaculture facilities and other properties, and often collide with aircraft. Their use of structures on and near water results in excessive amounts of bird droppings on boats and docks. Their presence near outdoor dining establishments, swimming beaches, and recreational sites can lead to negative interactions with people. Large amounts of gull fecal material pollutes water and beaches resulting in drinking water contamination and swim bans. A combination of dispersal techniques, exclusion and limited lethal control may reduce damage to …

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Amphibians Among Road-Rut Pools In West Virginia, Abby L. Sinclair Jan 2018

Amphibians Among Road-Rut Pools In West Virginia, Abby L. Sinclair

Theses, Dissertations and Capstones

As anthropogenic environmental stressors such as urbanization continue to increase, it is necessary to understand their impact on amphibian ecology. Due largely to their biphasic life history amphibians are negatively impacted by the destruction of lotic habitats i.e., wetlands for the creation of roads and urban centers. I examined the effects of three human-made road rut pools on the reproductive success and species richness of amphibians in southwest West Virginia from May to October 2012. I employed three detection techniques: drift fence pitfall trap arrays, funnel traps and dipnet sampling. Additionally, habitat covariates were taken (i.e., water depth) at each …

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Estimating Exploitation Rates In The Alabama Red Snapper Fishery Using A High-Reward Tag–Recapture Approach, Dana K. Sackett, Mattgew Catalano, J. Marcus Drymon, Sean P. Powers, Mark Albins Jan 2018

Estimating Exploitation Rates In The Alabama Red Snapper Fishery Using A High-Reward Tag–Recapture Approach, Dana K. Sackett, Mattgew Catalano, J. Marcus Drymon, Sean P. Powers, Mark Albins

University Faculty and Staff Publications

Accurate estimates of exploitation are essential to managing an exploited fishery. However, these estimates are often dependent on the area and vulnerable sizes of fish considered in a study. High-reward tagging studies offer a simple and direct approach to estimating exploitation rates at these various scales and in examining how model parameters impact exploitation rate estimates. These methods can ultimately provide a better understanding of the spatial dynamics of exploitation at smaller local and regional scales within a fishery—a measure often needed for more site-attached species, such as the Red Snapper Lutjanus campechanus. We used this approach to tag 724 …

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Compression And Relaxation Of Fishing Effort In Response To Changes In Length Of Fishing Season For Red Snapper (Lutjanus Campechanus) In The Northern Gulf Of Mexico, Sean P. Powers, Kevin Anson Jan 2018

Compression And Relaxation Of Fishing Effort In Response To Changes In Length Of Fishing Season For Red Snapper (Lutjanus Campechanus) In The Northern Gulf Of Mexico, Sean P. Powers, Kevin Anson

University Faculty and Staff Publications

A standard method used by fisheries managers to decrease catch and effort is to shorten the length of a fishery; however, data on recreational angler response to this simple approach are surprisingly lacking. We assessed the effect of variable season length on daily fishing effort, measured by using numbers of boat launches per day, anglers per boat, and anglers per day from video observations, in the recreational sector of the federal fishery for red snapper (Lutjanus campechanus) in coastal Alabama. From 2012 through 2017, season length fluctuated from 3 to 40 d. Daily effort, measured by using mean number of …

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The Life History Of Faxonius Rusticus (Girard, 1852) In Sunfish Creek, Monroe County, Ohio, Kyle Mcgill Jan 2018

The Life History Of Faxonius Rusticus (Girard, 1852) In Sunfish Creek, Monroe County, Ohio, Kyle Mcgill

Theses, Dissertations and Capstones

Crayfish are among the most imperiled faunal groups globally. The continued spread of invasive species is a major impact to crayfish. Invasive species, much like the native species, are often understudied. As declines continue, invasive species spread, and new species are discovered; additional life history studies are as important as ever for crayfish conservation. Life history data was collected for rusty crayfish (Faxonius rusticus) from October 2017 to September 2018 in Sunfish Creek, Monroe County, Ohio. Faxonius rusticus are native to the Ohio River drainage around Cincinnati, Ohio but have extensively expanded their range over the past 30 years. Sunfish …

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Growth Rate And Hatch Date Of Age-0 Fishes On Leech Lake, Minnesota Before Zebra Mussel Establishment, Kayla Morey, Emily Larson Jan 2018

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 …

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Seasonal Fluctuations Of Zooplankton, Dissolved Oxygen, And Temperature In Lake Bemidji, Minnesota, Cody Coyle Jan 2018

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 …

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Age-0 Walleye Growth Rates Following Spiny Water Flea Bythotrephes Longimanus Invasion, Joseph Amundson Jan 2018

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 …

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Evaluation And Demographic Response Of The Shovelnose Sturgeon Commercial Caviar Fishery In The Wabash River, Jessica L. Thornton Jan 2018

Evaluation And Demographic Response Of The Shovelnose Sturgeon Commercial Caviar Fishery In The Wabash River, Jessica L. Thornton

Masters Theses

Shovelnose sturgeon (Scaphirhynchus platorynchus Rafinesque) are considered one of the last commercially viable options for sturgeon roe harvest. Due to the collapse of several marine sturgeon fisheries and the Similarity of Appearances provision which protect shovelnose sturgeon in only a part of their range, the caviar fishery in the Wabash River remains an important point of supply for this lucrative natural resource. In this thesis, I presented an evaluation of the shovelnose sturgeon commercial caviar fishery in the Wabash River. More specifically, I described the demographic response of this population to continued exploitation over a 10-year period. Additionally, I …

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