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Articles 1 - 30 of 44
Full-Text Articles in Water Resource Management
Trophic Structure And Mercury Bioaccumulation In Walleye And Yellow Perch In The Upper And Lower Red Lake Basins, Marissa Pribyl
Trophic Structure And Mercury Bioaccumulation In Walleye And Yellow Perch In The Upper And Lower Red Lake Basins, Marissa Pribyl
Biology Graduate Theses
Mercury is a persistent global contaminant that biomagnifies through aquatic food webs, with dietary and environmental factors serving as the primary drivers of accumulation in fishes. Trophic structure and methylmercury dynamics in Walleye (ogaa; Sander vitreus) and Yellow Perch (asaawens; Perca flavescens) were investigated in the Upper and Lower Red Lake basins in Red Lake, Minnesota, during 2024-2025. Diets of Walleye and Yellow Perch were assessed through stomach dissections, and tissue samples from both species were analyzed for total mercury concentrations. Additional analyses included shiners (gigoozens; Notropis spp., Hudsonius spp.) along with a variety of freshwater fish and …
When Words Flow Like Water: How The Enbridge Line 3 Pipeline Environmental Impact Statement Failed To Prevent Hydrogeologic Harm In Minnesota, Carly Gutzmann
When Words Flow Like Water: How The Enbridge Line 3 Pipeline Environmental Impact Statement Failed To Prevent Hydrogeologic Harm In Minnesota, Carly Gutzmann
Journal of Earth and Life Science
For the aquifers of Minnesota, the environmental impact statement (EIS) was a promise of protection that never left the page. An environmental impact statement is meant to be an aid in the decision making process in order to ensure that projects consider potential environmental harms that may occur. However, they are often used instead as another regulatory box to check, rather than as active considerations when planning. As such, a project plan can be flawed from the start—if project developers only consider environmental impacts after they have already put considerable time, effort, and funding into their project as-is, they may …
Effectiveness Of Walleye Stocking In Winter Kill Lakes, Tyler Haus
Effectiveness Of Walleye Stocking In Winter Kill Lakes, Tyler Haus
Journal of Earth and Life Science
Winter kill events, marked by extensive fish mortality due to hypoxic conditions under the ice, are a common phenomenon in shallow eutrophic lakes, especially in the northern lakes in the northern United States. These events can drastically alter fish communities and often result in the elimination of top predators. Though these lakes will typically slowly bounce back to what they were in a couple of years. This study evaluates the effectiveness of walleye, Sander vitreus, stocking in lakes after a winter kill. For this study, four known winter kill lakes that are consistently stocked with walleye were studied. Pre- …
Assessing Urban–Rural Differences In Largemouth Bass Abundance In Minnesota, Jonathan Gates
Assessing Urban–Rural Differences In Largemouth Bass Abundance In Minnesota, Jonathan Gates
Journal of Earth and Life Science
Urbanization can significantly alter freshwater ecosystems and influence sport fish populations. This study examined differences in largemouth bass Micropterus nigricans catch-per-unit-effort (CPUE) between urban and rural lakes in Minnesota and evaluated temporal changes between 2000–2010 and 2011–2021. Forty lakes (20 urban, 20 rural) were selected using Minnesota Department of Natural Resources fisheries survey data. Lakes were classified using NLCD 2019 land cover data, with ≥10% developed land designated as urban. Nonparametric analyses (Wilcoxon rank-sum and signed-rank tests) were used to assess spatial and temporal differences in CPUE. Results showed that rural lakes had consistently higher median CPUE than urban lakes …
Neonicotinoid Bioaccumulation In Bluegill And Bullhead Within Lake Julia And Lake Zumwalde, Jake Stuber
Neonicotinoid Bioaccumulation In Bluegill And Bullhead Within Lake Julia And Lake Zumwalde, Jake Stuber
Journal of Earth and Life Science
Brown Bullhead Ameiurus nebulosus, Yellow Bullhead Ameiurus natalis, and Bluegill Lepomis macrochirus are unique in their stark differences. Bullhead are scaleless bottom feeders that can tolerate high pollution and low O2 conditions. In contrast, Bluegill are scaled, aggressive nesters and are less tolerant of high pollutants or low-oxygen conditions. Among these pollutants include a class of chemicals called neonicotinoids (hereafter referred to as neonics). Neonics are a class of insecticides primarily used within agriculture and pest management. Due to the effectiveness, application has escalated on a global scale. They have been well documented by many toxicology assessments. …
Powering The Machine, Draining The Planet: Whether U.S. Environmental Law Is Equipped To Regulate The Energy And Water Demands Of Ai Data Centers, Michael Marcu
Journal of Earth and Life Science
Artificial intelligence (AI) data centers have become one of the United States' fastest-growing and least-regulated sources of environmental stress. In 2024 alone, U.S. data centers consumed 183 terawatt-hours (TWh) of electricity more than the entire nation of Pakistan and consumed an estimated 17 billion gallons of water (IEA, 2025; Berkeley Lab, 2024). By 2030, electricity demand from these facilities is projected to reach 426 TWh, a 133% increase in six years (Pew Research Center, 2025). This paper examines whether the existing U.S. environmental regulatory framework put by the National Environmental Policy Act (NEPA), the Clean Water Act (CWA), and the …
Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez
Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez
Journal of Earth and Life Science
Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …
The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei
The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei
Journal of Earth and Life Science
Zebra mussels Dreissena polymorpha are an aquatic invasive species that has been spreading quickly throughout Minnesota water bodies since 1989. Zebra mussels are known to change certain morphological conditions in lakes such as turbidity, phytoplankton abundance, and aquatic invertebrate populations. However, studies showing impacts of the infestation of zebra mussels on the health of a fish community have been hard to prove due to a lack of repeated surveys and a suite of other confounding variables such as natural and seasonal variability, plant community, and lake morphometry. Therefore, the objective of this study is to determine whether zebra mussels have …
Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche
Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche
Journal of Earth and Life Science
When analyzing a population’s genetic makeup, looking at variation of individuals and populations is a crucial factor. The management of yellow perch will be aided by this information particularly in regard to stocking or relocation. Microsatellite loci were used to analyze the genetic population structure of yellow perch Perca flavescens within and among 29 sampling areas throughout Minnesota’s basins. Seven microsatellite DNA loci were evaluated, with heterozygosities ranging from 0.41 to 0.78. The Lower Mississippi basin samples showed higher numbers of alleles per locus and greater expected heterozygosities compared to other basins, with Lake Pepin (PEP) exhibiting the highest average …
Navigating Wastewater: Minnesota Mining Wastewater Permit Challenges And Evolving Compliance Standards, Madelaine Adamich
Navigating Wastewater: Minnesota Mining Wastewater Permit Challenges And Evolving Compliance Standards, Madelaine Adamich
Journal of Earth and Life Science
February of 2021 marked the beginning of Minnesota clearly establishing that groundwater qualifies as a Class 1 water in a legal battle involving United States Steel, the Minnesota Pollution Control Agency, WaterLegacy, Fond du Lac Band of Lake Superior Chippewa, the Minnesota Court of Appeals, and eventually the Minnesota Supreme Court (MNSC). Minnesota has a water classification system, as required by the federal Clean Water Act, with 7 classes of use. Class 1 waters are waters used for domestic consumption (MPCA 4, n.d.). According to Minnesota Statute § 7050.0220, the acceptable level for sulfate is 250 mg/L in Class 1 …
Aquatic Invertebrate Populations In Roadside Wetlands In Relation To Water Characteristics, Ellen P. Isakson
Aquatic Invertebrate Populations In Roadside Wetlands In Relation To Water Characteristics, Ellen P. Isakson
Journal of Earth and Life Science
The continual habitat destruction and draining of wetland systems makes the need to understand the ecology of roadside wetlands all the more necessary. Roadside wetlands provide valuable habitat to countless aquatic invertebrates, which can provide insight into the health of the wetland system due to their diversity. The objective of this study was to analyze the populations of aquatic invertebrates in roadside wetlands in relation to water characteristics such as pH, salinity, conductivity, water depth and temperature, and dissolved oxygen. This was done by collecting samples of invertebrate populations from roadside wetlands, in addition to data on water quality characteristics …
The Relationship Between Plant Density And Microplastic Concentration In The Water In Lake Bemidji, Mn, Arian Garcia
The Relationship Between Plant Density And Microplastic Concentration In The Water In Lake Bemidji, Mn, Arian Garcia
Journal of Earth and Life Science
Microplastics, plastic particles smaller than 5 mm, are an increasing environmental threat, particularly due to their widespread distribution and toxicity. While much research has focused on larger freshwater and marine ecosystems, the presence and impacts of microplastics in smaller inland lakes remain less understood. This study investigates the relationship between plant density and microplastic concentrations in Lake Bemidji, a smaller freshwater lake. A total of 30 water samples were collected across varying vegetation conditions, ranging from open water (0%) to 90% plant coverage. Microplastics were identified and categorized into six morphological types: fibers, fragments, films, spheres/beads, and foam. The samples …
A Sample Of Fish Communities In Beaver Ponds Of Northern Minnesota, Reed Cumberland, Rose Kuhlmann
A Sample Of Fish Communities In Beaver Ponds Of Northern Minnesota, Reed Cumberland, Rose Kuhlmann
Journal of Earth and Life Science
The North American beaver Castor canadensis is an ecosystem engineer and a keystone species to the environment. Beaver inhabit ponds and construct dams to build ponds that provide habitat for certain fish. Little information is provided on the species of fish that live in beaver ponds. The objective of this study is to sample the fish communities in beaver ponds while comparing the effectiveness of two styles of minnow traps. Twelve beaver ponds were selected in the Bemidji area to be sampled. The quantity and species caught in each style of trap were recorded to compare effectiveness of each trap …
The Effectiveness Of The Minnesota Buffer Law And Its Impacts On People, Ellen P. Isakson
The Effectiveness Of The Minnesota Buffer Law And Its Impacts On People, Ellen P. Isakson
Journal of Earth and Life Science
In January 2015, the then-governor of Minnesota Mark Dayton announced new legislation that would require 50-foot vegetation buffers along all waterways in Minnesota; this legislation would come to be known as the Minnesota buffer law, exact requirements being “perennial vegetative buffers of up to 50 feet along lakes, rivers, and streams and buffers of 16.5 feet along ditches” (Albert, 2017; MN Board of Water and Soil Resources [MN BWSR] 4 ). A buffer in the context of vegetation and natural resource management is a strip of vegetation around a body of water “designed to intercept stormwater runoff and minimize soil …
Does Depth Affect Zebra Mussel Length In Scalp Lake?, Zanden Mellen
Does Depth Affect Zebra Mussel Length In Scalp Lake?, Zanden Mellen
Journal of Earth and Life Science
Since its first sighting in 1996, zebra mussels Dreissena polymorpha have been confirmed in hundreds of Minnesota lakes. Not only were they found in lakes, but they are also found in rivers too. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The objective of this study was to see if there was a relationship between a zebra mussel length and the depth, they are found using shell length (mm) and depth (cm). The comparison of zebra mussel length and depth was done by performing a …
Long Term Trends In Mortality Rates Of A Smallmouth Bass Population, Caleb D. Anderson
Long Term Trends In Mortality Rates Of A Smallmouth Bass Population, Caleb D. Anderson
Journal of Earth and Life Science
Smallmouth bass Micropterus dolomieu are known as a popular sport fish for anglers. When a known smallmouth bass fishery appears to have a dwindling population, it raises questions about the population health. A common indicator of the health of the population is the mortality rate. By comparing mortality, conclusions can be made on whether smallmouth bass are dying at a different rate in the system over time. Therefore, the objective of this study was to see if there had been a significant change in smallmouth bass mortality over a span of thirty years in Round Lake (DOW:010204), Aitkin County, Minnesota. …
Relationship Between Fishing Hours And Number Of Fish Harvested From Upper Red Lake, Dylan Ohlenkamp
Relationship Between Fishing Hours And Number Of Fish Harvested From Upper Red Lake, Dylan Ohlenkamp
Journal of Earth and Life Science
Total hours fishermen spend fishing and total amount of fish harvested per year are some of the most important pieces of knowledge gained from creel surveys. They provide crucial information that assesses fisheries mortality and pressure. MN DNR uses their results from creel surveys to improve or impose regulations, and to maintain healthy fisheries. Based on results from similar studies, there is expected to be a positive relationship between hours fished and fish harvested. To determine the relationship between these two variables on Upper Red Lake, data from two years were selected when the variables were at their highest and …
Zebra Mussel Length-Weight Relationships Across Various Substrate Types In Lake Bemidji, Mitch Kehne
Zebra Mussel Length-Weight Relationships Across Various Substrate Types In Lake Bemidji, Mitch Kehne
Journal of Earth and Life Science
As of November 2021, zebra mussels were confirmed in 270 Minnesotan lakes with another 232 lakes listed as infested due to their connection or proximity to where zebra mussels have been found. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The goal of this study was to establish a length-weight relationship for the zebra mussel population in Lake Bemidji using shell length (SL) and wet weight (WW), as well as to assess substrate type and log transformed shell length as predictors of log transformed zebra …
Implications Of Condition Shifts On Shallow Lakes, Alicia Skolte
Implications Of Condition Shifts On Shallow Lakes, Alicia Skolte
Biology Graduate Theses
Shallow lakes have undergone condition shifts throughout time by natural causes, management actions, or a combination of the two. Because shallow lakes are especially vulnerable to shifts towards turbid conditions, management actions on shallow lakes have focused on water level/retainment, biomanipulations, the management/removal of non-native species, and land-use changes. This review compiles a summary on ecosystem shifts including a discussion on the frequency of shifts historically and the importance and causes of those shifts, trophic cascades, and the influence of introduced species in shallow lakes. This review will then examine case-studies of management-linked shifts and explain current shift theory. Next, …
Effects Of Salt Runoff On Aquatic Macroinvertebrate Colonies, Kendra Fink
Effects Of Salt Runoff On Aquatic Macroinvertebrate Colonies, Kendra Fink
Journal of Earth and Life Science
Aquatic macroinvertebrates bridge the gap in part between primary and secondary consumers, making them ecologically important for most aquatic systems. They are used as biotic indicators for water quality due to their sensitivity to pollutants and may be affected, specifically, by chloride ion concentrations in the water. Water quality can be evaluated by looking at species compositions and their respective tolerance values. To determine long-term effects of road salt on macroinvertebrate colonies, a total of 338 identified macroinvertebrates of 10 families (two generalized to class) at 9 sites were collected from before, after, and between three bridges on Turtle River …
Factors Influencing Aquatic Invertebrate Diversity In Mine Pit Lakes Along The Mesabi Iron Range, Jeremy Laurich
Factors Influencing Aquatic Invertebrate Diversity In Mine Pit Lakes Along The Mesabi Iron Range, Jeremy Laurich
Journal of Earth and Life Science
Restoration of mine pit lakes for recreation is going to be very important for the future of Minnesota’s Mesabi Iron Range area. As many as 250 lakes will need to be restored in the future along this 100-kilometer-long swath of mining country. Information regarding the organisms that currently inhabit these lakes is important for future restorations to be a success. The focus of this study was to identify the types of aquatic invertebrates present in pit lakes and to identify some of the factors that influence their abundance and diversity. During this study, invertebrate samples were taken along the shore …
Is There A Relationship Between Aquatic Vegetation And Amphipod Stocking Mortality?, Alaina Taylor
Is There A Relationship Between Aquatic Vegetation And Amphipod Stocking Mortality?, Alaina Taylor
Journal of Earth and Life Science
Amphipod occurrence and abundance has declined in the Prairie Pothole Region (PPR). Wildlife managers have stocked prairie pothole wetlands with Gammarus lacustris since 2018 to establish self-sustaining populations. G. lacustris have been detected in only 2 of 22 stocked basins, suggesting that they have died or failed to reproduce in most stocking attempts. Aquatic plant surveys were conducted in stocked wetlands and compared to data from surveys of wetlands with naturally occurring populations to understand if G. lacustris would be expected to survive in stocked wetlands based on characteristics of the aquatic vegetation communities. SAV coverage was significantly higher in …
Exploring The Genetic Variability Of Zebra Mussels Dreisenna Polymoprha, Maxwell Carr
Exploring The Genetic Variability Of Zebra Mussels Dreisenna Polymoprha, Maxwell Carr
Journal of Earth and Life Science
Zebra Mussels Dreisenna polymorpha are one of the most well-known invasive species here in the United States. This species can take over watersheds very quickly, causing damage to both the ecosystem and man-made structures. The basic physical behavior of this species has been well documented, but the invasive North American Zebra Mussel is much more aggressive and therefore causes more damage in the Great Lakes region compared to its native waters. Genetic variation may be playing a very large role in how and why D. polymorpha is causing such large problems for stakeholders in the United States. This review cites …
Effectiveness Of Endothall Treatment In Reducing Potamogeton Crispus In Lake Julia, Jake Sorensen
Effectiveness Of Endothall Treatment In Reducing Potamogeton Crispus In Lake Julia, Jake Sorensen
Journal of Earth and Life Science
Curly leaf pondweed Potamogeton crispus, is a submerged aquatic plant non-native to North America. It was most likely introduced when common carp Cyprinus carpio were intentionally brought to the Midwest. Endothall is an aquatic herbicide commonly used to control curlyleaf pondweed in lakes. This study focused on collecting data from Lake Julia in Sherburne County, MN. Lake Julia is treated annually in the spring to control curlyleaf pondweed. The results show treatment areas saw a significant increase in vegetation density compared to control areas (P < 0.01). Changes in percent vegetation coverage by date were insignificant (P = 0.24). No significant signs of fish kills were observed. Because this study looked at overall vegetation coverage instead of specifically curlyleaf pondweed, we cannot conclude the increase in vegetation coverage was from curlyleaf pondweed alone. Based on the results from Poovey et al. (2002) we would expect lower vegetation coverage in treatment areas instead of the increased vegetation coverage observed in our study. This suggests the possibility that the endothall treatment successfully killed curlyleaf pondweed in treated areas, which allowed for new growth of submerged aquatic plants to take place as water temperatures increased.
Effect Of Beaver On Brook Trout Habitat In North Shore, Lake Superior Streams, Kathryn Renik
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 …
Changes In Walleye Fecundity And Egg Size Before, During, And After Rehabilitation Of The Red Lakes Fishery, Benjamin J. Miller, Benjamin D. Erb
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 …
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.
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 …
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 …