Laboratory and Basic Science Research Commons^™

Enhancing Walleye (Ogaa) Recruitment: Evaluating Assisted Reproduction As A Mitigation Strategy, Douglass Keiser

Biology Graduate Theses

Over the past several decades, cold- and cool-water fish populations across the Upper Midwest, including Minnesota and Wisconsin, have shown troubling signs of decline. Among the most affected is the walleye/Ogaa (Sander vitreus), a species deeply embedded in the ecological balance, cultural identity, and economic vitality of the region, and central to the lifeways, treaty-reserved rights, and resource stewardship of Tribal Nations, including Ojibwe communities across the Upper Midwest. Despite ongoing stocking efforts and harvest regulations, many lake systems have experienced persistent declines in natural recruitment, prompting resource agencies to investigate the underlying causes. One such system is …

Largemouth Bass Diet Changes Through The Summer In Central Minnesota, Ethan Kunz

Journal of Earth and Life Science

Largemouth Bass Micropterus nigricans is one of the most widespread fish species in the world, due in part to human introduction for angling. Largemouth Bass are opportunistic predators that will consume the largest prey they can often find; however, it has been shown that their diet mainly consists of invertebrates such as crayfish, with less focus on other fish species. This research aimed to determine what the Largemouth Bass diets in Central Minnesota consist of, and how they may change from the beginning of summer through the beginning of fall. A total of 174 Largemouth Bass were sampled from late …

Statewide Northern Pike Response To Minnesota’S 2018 Regulation Change, Elijah Wozniak

Journal of Earth and Life Science

Management of northern pike (Esox lucius) is challenging because it attempts to balance ecological sustainability with angler interests. Northern pike often stunt their own growth by diminishing the size and abundance of prey fish, their food source. Anglers are often displeased when small pike occur in high population densities. In response to populations of small northern pike, the DNR implemented a new, statewide northern pike regulation in 2018. The objective of this study was to determine whether the regulation successfully changed the mean weight, length, and CPUE of northern pike in Minnesota. The secondary objective was to test …

Comparison Of Calcified Structures To Estimate Ages Of Northern Pike Esox Lucius In Various Lakes, Kaed Rauk

Journal of Earth and Life Science

Northern pike Esox lucius are a dominant predatory fish in many aquatic systems. They can have significant impacts on the ecosystems they inhabit and are also a popular game fish among anglers. However, northern pike are a difficult species to age accurately. This study aimed to compare calcified aging structures to identify trends and determine which structure provides the most accurate age estimates. A total of 119 northern pike were sampled, and multiple structures from each fish were independently aged by two readers. The coefficient of variation (CV) was calculated for each structure to assess precision. Sectioned sagittal otoliths exhibited …

Size Structure Comparison Of Bluegill In Lakes With And Without Special Regulations, Jenna Lawin

Journal of Earth and Life Science

Lots of individuals have mixed feelings about special regulations for all sorts of game fish species such as northern pike Esox lucius, crappie Pomoxis spp., sunfish Lepomis spp., and so on. One species commonly sought after by many is bluegill Lepomis macrochirus. Bluegill are often deemed easy to find, catch, and clean. This study looks at three different categories of lakes (all lakes contain bluegill populations). The three categories are lakes with a five sunfish limit, lakes with a ten sunfish limit, and lakes without any special regulations. This study provides valuable insight into the size …

Size Structure Of Black Crappie And Bluegill In Northern, Eastern, Western, And Southern Minnesota, Ray Anderson

Journal of Earth and Life Science

Fish size structure is an important factor in a fishery population. Panfish such as black crappie Pomoxis nigromaculatus and bluegill Lepomis macrochirus play a major role in the health of fisheries. Five lakes from southern, northern, eastern, and western Minnesota were selected for analysis. Data were collected using standard sampling methods, including gill nets, electrofishing, and fyke nets. Length-frequency distributions were created to assess size structure in each region. Relative abundance was measured using catch per unit effort. Data analysis included a one-way ANOVA to compare Proportional Size Distribution (PSD) values and the distribution of fish sizes among regions. Chi-square …

Specific Measurements Of A Yellow Perch Head Compared To The Total Length, Alex Timm

Journal of Earth and Life Science

Yellow Perch Perca flavescens is a popular fish for harvesting in Minnesota. Because of this the Minnesota Department of Natural Resources survey populations with gill nets, however, some water bodies have Rusty Crayfish Faxonius rusticus that commonly consume most of the body leaving only the head to be accurately measured. The goal of this research was to see if there is a relationship between specific measurements of the head and the total length of the fish. The number of Yellow Perch sampled in this study was 72 and all came from Lake Bemidji in Minnesota during the month of October …

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

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.

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 …

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 …

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 …

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 …

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 …

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 …

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 …

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 …

Western Australian Fisheries - Key Achievements 1997-1998, Fisheries Western Australia

Fisheries Published Reports

The WA fishing community can look back at the past year with considerable satisfaction.

Close partnership arrangements between Government, industry, the community and Fisheries Western Australia have both consolidated and advanced the State's position at the forefront of sustainable management of marine environments and fish resources.

Together, commercial fishing and recreational fishing make 􀁚 annual $1.5 billion contribution to the Western Australian economy. Through a carefully balanced portfolio of policies and initiatives the Coalition is making sure that both sectors continue to prosper, while at the same time ensuring that future generations inherit a marine environment which we are all …