Aquaculture and Fisheries Commons^™

Integrating Multi-Method Monitoring To Characterize Seasonal Habitat Use Of Green Sturgeon (Acipenser Medirostris) In Humboldt County, California, Olivia S. Boeberitz

Cal Poly Humboldt theses and projects

Green sturgeon (Acipenser medirostris) are a long-lived, anadromous, iteroparous species that spawns in large West Coast North American rivers but ranges widely in the coastal ocean. For coastal California Native American Tribes, green sturgeon are a vital part of their cultural heritage and traditions, and central to their food security. Two genetically distinct population segments (DPSs) of green sturgeon are recognized in the United States, Canada, and Mexico; the southern DPS is listed as “threatened” under the Endangered Species Act and the northern DPS is considered of “conservation concern.” Although green sturgeon are known to use large estuaries …

The Depuration Of Microplastic Pollution In Aquacultured Indian River Lagoon Oysters, Lee Nguyen

Honors Undergraduate Theses

Plastics are widely used in consumer goods and industrial manufacturing, and their degradation into microplastics (MP, size < 5 mm) has created an emergent environmental pollutant. Plastics readily enter aquatic environments, where they accumulate additional contaminants and bioaccumulate in organisms. While MP contamination in marine ecosystems is well documented, less is known about MP presence in aquacultured shellfish. Depuration, the process of purging contaminants from shellfish, is conducted in sterile seawater without food, which may cause oyster starvation and death. To date, MP depuration has not been examined in the aquacultured eastern oyster (Crassostrea virginica) in published studies. This study had 3 goals: 1) evaluate the effects of algal feed on oyster survival during depuration, 2) determine the effect of algal feed on depuration effectiveness, and 3) investigate the effect of a ten-day depuration on MP concentration in aquacultured C. virginica soft tissue. MP were quantified in oyster tissues, biodeposits, and in industrial algal feed. Tissues were digested using alkaline solutions, manually examined via microscopy, and analyzed using Fourier-Transform Infrared Spectroscopy (FTIR) to investigate MP polymer …

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

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 …

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 …

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. …

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 …

Oyster Drill (Stramonita Haemastoma Complex) Habitat Preferences In A Shallow Coastal Estuary, Coen Mcgarrah, Cynthia Lupton, Eric Sparks, Jennifer L. Debose

Gulf and Caribbean Research

Southern oyster drill snails (Stramonita haemastoma complex) are nuisance organisms within the Gulf of Mexico. This is due to their damaging impact on recovering and farmed oyster (Crassostrea virginica) populations, which are one of the drills’ main food sources. Oyster reef recovery and increased aquaculture production are priorities for Mississippi and the wider northern Gulf coast. The Grand Bay National Estuarine Research Reserve (NERR) hosts multiple oyster reef restoration sites within its boundaries, yet no comprehensive survey of oyster drill abundance has been conducted in this area to date. Additionally, knowledge of oyster drill preferences for sediment …

Evaluating Species At Risk In Data-Limited Fisheries: A Productivity-Susceptibility Analysis For Marine Aquarium Fish, Gabrielle A. Baillargeon, Alice A. Wynn, Jemelyn Grace P. Baldisimo, Michael F. Tlusty, Andrew L. Rhyne

Biological Sciences Faculty Publications

The marine aquarium trade (MAT) is a significant global industry harvesting millions of wild-caught, live coral reef fishes for public and private aquaria markets in the United States and Europe annually, while supporting fisher livelihoods in the Indo-Pacific. This diverse and species-rich trade is considered data-limited, creating barriers to quantifying the current and future socio-ecological sustainability of the fishery. We present a revised and expanded productivity–susceptibility analysis (PSA) that serves as a holistic risk assessment to estimate the vulnerability of marine aquarium fish to overfishing. Our global analysis includes 306 species that are actively in trade. Improvements to the PSA …

Does Fishery Management For Groupers (Teleostei: Epinephelidae) Protect Them Effectively? Context From The Iucn's Red List Of Threatened Species, Sean T. Fennessy, Christi Linardich, Kevin Rhodes, Joao P. Barreiros, David Pollard, Eloy Sosa-Cordero, Felicia Coleman, Alfonso Aguilar-Perera, Christopher R. Malinowski, Thierry Brulé, Pedro Afonso, Kayan Ma, Min Liu, Muktha Menon, Colin Wen, Stanley K. H. Shea, Sean N. Porter, Matthew Craig, Yvonne Sadovy De Mitcheson

Biological Sciences Faculty Publications

Worldwide, groupers (Epinephelidae) are commercially valued fishes, which also play key ecological roles on tropical and subtropical reefs. In 2007 and 2016, the IUCN's Groupers and Wrasses Specialist Group assessed all 160+ grouper species, with 17 of these being identified as threatened in 2016 and the major threat factor being overexploitation. Our present study aimed to identify whether management measures (MMs) for previously assessed groupers were established, whether these measures aligned with IUCN's Red List categories, and whether they effectively protect grouper populations. Experts in grouper biology and management assigned scores per grouper species based on the extent to which …

Mitochondrial Genome Of The Indo-Pacific Mesophotic Coral Leptoseris Columna (Scleractinia: Agariciidae) Assembled Using Pacbio Long-Read Sequencing, Nomita Rani Adhikary, Daniel J. Barshis, J. Antonio Baeza

Biological Sciences Faculty Publications

Leptoseris columna, a mesophotic coral species belonging to the family Agariciidae, is distributed throughout the Indo-Pacific region. This species is considered as of "Least concern" by the IUCN, yet, faces multiple local and global stressors. To support conservation plans, this study sequenced and characterized the complete mitochondrial genome of L. columna. The complete mitochondrial genome of Leptoseris columna was assembled using PacBio long-reads with a coverage of 459× per bp. The AT-rich mitochondrial genome of Leptoseris columna is 18,546 bp long and comprises 13 protein-coding genes (PCGs), 2 transfer RNA genes (trnM and trnW), and 2 ribosomal RNA …

Larval Genomics As A Viable, Fisheries-Independent Tool For Investigating Population Structure In Tropical Pacific Tunas, Jacob E. Jaskiel, Hannah E. Aichelman, Giulia Anderson, Louw Claassens, James E. Fifer, Christina M. Hernandez, Alexa K. Huzar, Joel K. Llopiz, Jan W. Witting, Sean P. Mullen, Randi D. Rotjan

Biological Sciences Faculty Publications

Understanding how dispersal, life history, and environmental variability shape genetic connectivity in the open ocean remains a central challenge in evolutionary biology. Highly migratory marine predators like tunas have traditionally been considered genetically homogeneous across ocean basins, yet emerging genomic evidence suggests that cryptic population structure can persist even in species with high gene flow and large effective population sizes. We used 2bRAD sequencing of 348 larval and subadult skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares), and bigeye tuna (T. obesus) collected from the central Pacific across 7 years of sampling to examine species boundaries, …

A Re-Evaluation Of Atlantic Bluefin Tuna (Thunnus Thynnus) Spawning Distribution In The Western Atlantic Ocean, David E. Richardson, Katrin E. Marancik, Malgorzata Adamus, Elizabeth A. Broughton, Robert K. Cowen, Trika Gerard, Christina M. Hernández, John J. Hoey, Joel K. Llopiz, Molly E. Lutcavage, Estrella Malca, Debra L. Palka, Lourdes Vásquez-Yeomans, Harvey J. Walsh, C. Michelle Willis, Glenn A. Zapfe

Biological Sciences Faculty Publications

There is currently a lack of consensus on the spatial, seasonal and decadal-scale patterns of Atlantic bluefin tuna (Thunnus thynnus) spawning in the western Atlantic Ocean. We compiled ichthyoplankton and reproductive data to characterize bluefin spawning patterns and the uncertainty in these patterns. Ichthyoplankton data indicates that bluefin spawn in the Gulf of America/Gulf of Mexico, northwest Caribbean Sea, north of the Bahamas, along the inshore edge of the Florida Current off the Carolinas and in the western Slope Sea. Reproductive studies identified these same spawning areas, as well as the Windward Passage and waters east of the …

Rate Response Of Curlyleaf Pondweed And Native Plants To Flumioxazin In Minnesota Lakes, Pearl J. Jensen

All Graduate Theses, Dissertations, and Other Capstone Projects

Curlyleaf pondweed (Potamogeton crispus L.) is an invasive aquatic plant present across the United States that causes significant recreational issues, outcompetes native plant species, and depletes water quality. Before senescing in mid-summer, curlyleaf pondweed forms a large number of turions that can lay dormant in the sediment for several years. Typical herbicide management of this species occurs in early spring to target the plant before turion production occurs and while native plants are dormant. Flumioxazin has shown potential in curlyleaf pondweed management in small scale studies, but its effects have not been assessed in operational management. In this study, treatments …

Using Genetic Analysis To Infer Familial Relationships Of Westslope Cutthroat Trout In The Lower Priest River, Idaho, Kolby Emtman

EWU Masters Thesis Collection

The Westslope Cutthroat Trout (Oncorhynchus lewisi) is a native species of salmonid that holds both cultural and ecological significance in the Idaho Panhandle region of the United States. Within this region, the Priest River is a major contributor of migrant Westslope Cutthroat Trout to the Clark Fork Pend Oreille basin. This study aimed to estimate the proportion of juveniles that have at least one migrant parent, illustrate gene flow using juvenile half sibling relationships, and showcase varying levels of spawning success using juvenile full sibling relationships. Sampling of juvenile individuals occurred in 11 tributaries of the Priest River over …

Relationships Between Benthic Macroinvertebrate Communities And Environmental Conditions In Headwater Tributaries Of The Pend Oreille Lake Watershed, Idaho, Devlin Mee

EWU Masters Thesis Collection

Benthic macroinvertebrates are widely used indicators of stream condition, and their communities respond to thermal and land-use conditions in headwater streams. This study characterized macroinvertebrate biomass, community composition, and diversity across forested headwater tributaries of the Pend Oreille lake watershed in northern Idaho, and examined their relationships with summer temperature, land development, and road proximity. Samples from thirteen streams collected in 2024 were identified to genus, measured, and converted to estimated biomass using published length–mass regressions; ten streams had recovered temperature loggers. Because environmental variables were characterized once per stream, all analyses were conducted at the stream level.

Estimated total …

If You Build It, Will They Stay? Fish Communities Continue To Utilize Restored Habitat A Decade Following An Instream Restoration, Alexis L. Vandenberg

Masters Theses

Lotic ecosystems are degraded at an alarming rate due to anthropogenic activities. In order to combat these changes, stream restorations are implemented to improve conditions such as water quality, habitat heterogeneity, and bank stability. However, the impacts of these restorations are often understudied and long-term impacts are unknown. Restorations are typically designed to be ‘fish attractors’; this idea is known as the ‘Field of Dreams hypothesis’ – ‘if you build it, they will come’. This study uses data collected in Kickapoo Creek, Coles County from 2009 to 2015 and again in 2021 and 2022 to assess the long-term impacts of …

Compositional And Functional Shifts In Fish Community Structure In Response To Low-Head Dam Removals, Joshua D. Bruegge

Masters Theses

Low-head dams serve as intermittent barriers to aquatic connectivity and directly alter both upstream and downstream habitats and biotic communities. In 2018 and 2019, two low-head dams in the Vermilion River watershed of eastern Illinois were removed, reconnecting over 1,700 kilometers of upstream habitat within the basin. To determine the impacts of these dam removals, fish community surveys were conducted at 12 fixed sites across three reaches in two rivers from 2012-2022. This study assessed reach-specific temporal responses of the fish community and habitat characteristics. I linked trait expressions within the fish community to abiotic variables using the co-inertia RLQ …

Impact Of Water Level Fluctuations On Fish Populations In Eastern South Dakota Rivers, Benjamin Schall

Electronic Theses and Dissertations

Riverine systems are highly dynamic, and changes in flow conditions can impact the population dynamics of fishes. Increased flows from historical averages in eastern South Dakota rivers have likely impacted fish populations. The goals of this study were to 1) better understand the changes in resource use by Blue Suckers Cycleptus elongatus through retrospective eye lens stable isotope analysis, 2) determine the effects of record flooding in the James River on complex woody habitat and Flathead Catfish Pylodictis olivaris population structure, and 3) assess the influence of river discharge and temperature on Channel Catfish Ictalurus punctatus and Flathead Catfish condition …