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Articles 61 - 90 of 98

Full-Text Articles in Laboratory and Basic Science Research

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 …


Changes In Walleye Fecundity And Egg Size Before, During, And After Rehabilitation Of The Red Lakes Fishery, Benjamin J. Miller, Benjamin D. Erb Jan 2019

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 …


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 …


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.


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 …


Legacy Contaminants In The Northern Gulf Of Mexico Shelf, Jessica N. Landry Mar 2018

Legacy Contaminants In The Northern Gulf Of Mexico Shelf, Jessica N. Landry

LSU Master's Theses

The Mississippi River watershed is the third largest in the world and drains from 31 states in the United States. Due to its route through the U.S., it passes through hundreds of EPA labeled Superfund sites as well as agricultural and suburban watersheds. These sites are known to have historical chemical contamination, and as a result chemicals can be transported by runoff down the Mississippi River into the Gulf of Mexico where their ultimate fate is unknown. Organochlorine chemicals are known to be persistent and are found in agricultural land as well as US EPA Superfund sites, especially DDT, PCBs, …


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 …


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 …


Hunter Harvest Effect On The Breeding Bird Population Of Northern Pintail Anas Acuta In North America, Matthew Wang Jan 2018

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 …


Elucidating The Effects Of Thiamethoxam Neonicotinoid On Honey Bee Learning Using The Proboscis Extension Response, David J. Shepherd May 2017

Elucidating The Effects Of Thiamethoxam Neonicotinoid On Honey Bee Learning Using The Proboscis Extension Response, David J. Shepherd

Undergraduate Honors Theses

In this study, the effects of the neonicotinoid pesticide, thiamethoxam, are examined through the Proboscis Extension Response (PER) in honey bees (Apis mellifera). PER is a form of classical conditioning applied to honey bees through scent and reward association which quantifies learning rates. Results between groups treated with thiamethoxam did not differ significantly from untreated control groups. Potential reasons for these results are discussed. The method and experimental apparatus for testing the PER assay are also discussed.


Estimating Seasonal Variation In Condition Of Yellow Perch, Emily Anne Powers Mar 2017

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 Jan 2017

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 Jan 2017

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 …


A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London Jan 2017

A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London

Cal Poly Humboldt theses and projects

Intermittent streams are common throughout the world and comprise 60% or more of total river lengths in the conterminous United States. Despite their prevalence, intermittent streams are understudied, particularly first-order headwater streams, which are vital for maintaining the function, health and biotic diversity of river networks. In June 2016, I sampled five intermittent and five perennial headwater streams in the Mattole River watershed in northwestern coastal California, USA, to compare benthic macroinvertebrate (BMI) assemblages between intermittent and perennial streams. BMI samples were collected using a 500µm mesh D-net at eight randomly located riffles along a 150-m reach, and then composited, …


Burbot Growth Rates In A Northern Mesotrophic Lake, Samuel J. Peterson Jan 2017

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 Jan 2017

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 …


Assessment Of American White Pelican Predation And Reproductive Success Of Walleye In The Tamarac River, Mn, Jake Graham May 2016

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 …


Identification And Quantification Of Zooplankton In Ne Ohio Drinking Water Reservoirs, Michael Vigorito Jan 2016

Identification And Quantification Of Zooplankton In Ne Ohio Drinking Water Reservoirs, Michael Vigorito

Williams Honors College, Honors Research Projects

Cyanobacteria, or blue-green algae, are present in most freshwater ecosystems and are usually harmless. When these algae swell in numbers, they release harmful toxins that can be detrimental to animal and human health, and can destroy ecosystems. For this reason, many scientists and engineers have studied these harmful algal blooms in an attempt to predict, prevent, or control them to keep people and ecosystems safe. One of the variables in this investigation is the presence and quantity of zooplankton. These animals could play an important role in the prevalence of cyanobacteria, but more information is needed to determine what that …


Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman Sep 2015

Heterogeneous Oxidation Of Catechol, Elizabeth A. Pillar, Ruixin Zhou, Marcelo I. Guzman

Chemistry Faculty Publications

Natural and anthropogenic emissions of aromatic hydrocarbons from biomass burning, agro-industrial settings, and fossil fuel combustion contribute precursors to secondary aerosol formation (SOA). How these compounds are processed under humid tropospheric conditions is the focus of current attention to understand their environmental fate. This work shows how catechol thin films, a model for oxygenated aromatic hydrocarbons present in biomass burning and combustion aerosols, undergo heterogeneous oxidation at the air–solid interface under variable relative humidity (RH = 0–90%). The maximum reactive uptake coefficient of O3(g) by catechol γO3 = (7.49 ± 0.35) × 10–6 occurs for …


Microbial Communities Of The Providence River, Jacqueline Kratch Apr 2015

Microbial Communities Of The Providence River, Jacqueline Kratch

Honors Projects in Science and Technology

The Providence River has been industrialized for over one-hundred years. Industries such as oil storage and metal recycling facilities have left high levels of pollutant metals, including lead (Pb), in the soil and water. The elevated Pb concentrations in these environments influence the selection of Pb resistance mechanisms in the bacterial community1. One mechanism of heavy metal resistance is the Pb efflux pump, consisting of proteins in the cell membrane that aid in the transport of Pb out of the cell2. In this study we investigated the co-occurrence of Pb efflux pumps and antibiotic efflux pumps in bacteria from Pb …


Effects Of River Current Inflow On Dissolved Oxygen And Temperature Of Refuge Zones For Cisco In Lake Bemidji, Bryant C. Swenson Jan 2014

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 …


Changing Body Condition In Walleye With Reference To Ideal Sample Size Requirements, Kevin Longtin Jan 2014

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 …


The Effects That Liquid And Solid Cattle Manure Have On The Water Quality Of Drainage Ditches In Putnam County, Ohio, Janelle Horstman Jan 2014

The Effects That Liquid And Solid Cattle Manure Have On The Water Quality Of Drainage Ditches In Putnam County, Ohio, Janelle Horstman

Honors Projects

Lake Erie has experienced harmful algal blooms with increased frequency since the mid-1990s due to excess nutrients from Rivers, such as the Maumee River, and largely agricultural watersheds. Nonpoint source pollution from agriculture contributes to eutrophication, algal blooms, and the degradation of water quality. This creates stress on aquatic fauna, reduced aesthetic quality, odor, and limits of the water for usage of drinking, recreation, and industry. This research paper asks what the contributions of having access to manure application records, soil records, and information about antibiotics have on what is known about manure management and antibiotic resistance, which has been …


Defining The Physiochemical, Biological And Habitat Requirements For The Upper Extant Of Oncorhynchus Mykiss Distribution, Emily Powers Jan 2014

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 Jan 2014

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 …


The Impact Of Dams On Nitrogen Cycling In The Messalonskee Stream, Rebecca K. Forgrave Jan 2014

The Impact Of Dams On Nitrogen Cycling In The Messalonskee Stream, Rebecca K. Forgrave

Honors Theses

The Messalonskee Stream in central Maine has five hydroelectric dams on 16.6km. Each dam drastically changes the flow regime of the stream, dividing it into segments with different patterns of sediment settling and organic matter retention. I investigated how these disruptions impact nitrogen cycling, specifically nitrification rates above and below each dam. I expected higher nitrification rates above the dams, where levels of organic matter are higher, and lower rates below the dam where scouring removes organic matter and fine sediment from the streambed. I measured sediment nitrification rates with a nitrapyrin-inhibition assay and potential drivers of nitrification including sediment …


Winter Survival Strategies Of Benthic Invertebrates In Temporary Habitats In A Northern Minnesota Lake, Cal Oldenburg Jan 2014

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 …


White Bass Assessment In Regards To Changes In Water Level On Lake Traverse, Aaron Wilson Jan 2013

White Bass Assessment In Regards To Changes In Water Level On Lake Traverse, Aaron Wilson

Journal of Earth and Life Science

Until recently the white bass Morone chrysops has been somewhat ignored by anglers, more so in Minnesota than other states; most likely due to their limited distribution throughout the state. However, with more anglers becoming aware of the sporting and culinary potentials of white bass, interests have risen. With this rise in angler interest, there should be a rise in white bass assessments. Knowing what factors may be influencing white bass population dynamics will allow fisheries professionals to better manage and protect white bass fisheries. White bass are often found in rivers and impoundments were dams are present and water …


Brown Trout Spawning Location And Relationship To Suitable Winter Habitat, Matthew L. Skoog Jan 2013

Brown Trout Spawning Location And Relationship To Suitable Winter Habitat, Matthew L. Skoog

Journal of Earth and Life Science

Brown trout are a popular game fish throughout much of the world. Understanding habitat requirements is necessary for the successful management of brown trout. This study looks at the spawning habitat preferences and relationship of redd location to wintering habitat of brown trout in the Straight River, Minnesota. Brown trout in the Straight River were found to spawn in similar habitat to brown trout looked at in previous literature. All redds were located on gravel substrate. Seventy eight percent of redds were associated with some sort of cover. Water velocities at the redd sites. (mean=0.456 ms/cm), dissolved oxygen (mean=9.78 mg/L), …


Comparison Of A Length Size Limit Of Northern Pike Population On Two Lakes In North Central Minnesota, Ethan A. Puttonen Jan 2013

Comparison Of A Length Size Limit Of Northern Pike Population On Two Lakes In North Central Minnesota, Ethan A. Puttonen

Journal of Earth and Life Science

Fisheries managers use length size limits on northern pike (Esox lucis) to improve the size structure in select lakes. The objective of this study was to compare two similar lakes, one with a length size limit and one without, to determine if a length size limit is improving the northern pike size structure. Blueberry Lake showed a higher abundance of larger fish than Stocking Lake. Of the fish caught, 25% in Blueberry Lake were over 600 mm (24 in), and were in the protected slot. Stocking Lake had a smaller portion of fish of this size with only …