Aquaculture and Fisheries Commons^™

Factors Influencing Mortality Of Stocked Rainbow Trout In Black Hills Reservoirs, Charles A. Mordhorst

Electronic Theses and Dissertations

Because return to angler is an important outcome of put-and-take fisheries, understanding mortality of stocked Rainbow Trout is fundamental to managing these fisheries. Harvest rates of stocked Rainbow Trout Oncorhynchus mykiss in the Black Hills of South Dakota are believed to be below management objectives. Rainbow Trout not harvested by anglers are assumed to be lost to various sources of mortality, raising concerns about the cost of the Rainbow Trout stocking program relative to the benefit provided to anglers. (Simpson 2008). This study evaluated the factors influencing mortality of Rainbow Trout stocked into Black Hills reservoirs. We assessed the effects …

Living In A Gradient: The Influence Of Water Temperature Variation On Development, Settling Time And Survival Of Pallid Sturgeon Larvae In The Missouri River, Maria Elizabeth Erceg

Electronic Theses and Dissertations

Pallid Sturgeon (Scaphirhynchus albus) are a federally endangered species experiencing widespread reproduction and recruitment failures. Recruitment failure is hypothesized to be caused by habitat modifications made to the Missouri River that disrupt connectivity and alter temperature profiles downstream of constructed dams. Hypolimnetic releases from Missouri River dams affect the temperature downstream, creating colder conditions during the downstream drifting phase for dispersing larvae. Understanding the influence of water temperature changes on larval development is crucial for recovery efforts. In this study, we evaluated the effects of water temperature daily heating rate on energy use, settling behavior, and growth rate of endogenously …

Effects Of Harvest Regulations And Post-Release Hooking Mortality On Walleye Populations In South Dakota, Cade Lyon

Electronic Theses and Dissertations

Harvest regulations are commonly implemented to manipulate fisheries stocks. By regulating the size and number of fish that are harvested by anglers, managers are able to meet the goals and needs of regions. However, these management actions come with the potential for negative consequences. Overexploitation due to less restrictive harvest regulations can cause collapses in fisheries populations. In addition, indirect consequences such as hooking mortality brought on by length-based regulations can also be detrimental to populations. In this study, I investigated the effects of various harvest regulations on Walleye populations in three western South Dakota irrigation reservoirs: Angostura, Belle Fourche, …

Assessing Habitat Suitability Of Ribbed Mussels (Geukensia Demissa) In Georgia Salt Marshes By Examining Predicted Mussel Densities And Mussel Population Parameters, William K. Annis Jr

Electronic Theses and Dissertations

Geukensia demissa (ribbed mussel) is an ecology important bivalve that has the potential to contribute to salt marsh restoration. Understanding the factors that contribute to the distribution of mussels can help inform managers on choosing locations to optimize the survivorship of mussels in restoration projects. This study sought to model mussel densities across the coast of Georgia and to compare predicted mussel densities with mussel population parameters as means to gauge habitat suitability. Mussel densities were collected through field surveys across a range of salt marshes along the coast of Georgia and were compared with spatial data such as distance …

Distribution, Density, Movement, And Support For Management Of Mountain Sucker, Pantosteus Jordani, In The Black Hills Of South Dakota, Seth J. Fopma

Electronic Theses and Dissertations

Mountain Sucker, Pantosteus jordani, is a cold-water species native to the Intermountain West. Fringe populations of Mountain Sucker have experienced declines in recent decades. The population of Mountain Sucker found in the Black Hills of South Dakota represents the eastern fringe of the species’ native range. Recognized as both an indicator of biologic health and as a species of greatest conservation need in South Dakota, recent studies have suggested significant declines in both distribution and abundance. Despite the recent study of Mountain Sucker in the region, increased understanding of Mountain Sucker ecology is needed to effectively manage for the conservation …

Influence Of Mink Predation On Brown Trout Survival And Size-Structure In Rapid Creek, South Dakota, Austin Galinat

Electronic Theses and Dissertations

I compared movement, home range, habitat selection, and mortality among radio-tagged Brown Trout (Salmo trutta) at an American Mink (Neovison vison)-removal site, improved habitat site, and an undisturbed stream site in Rapid Creek, South Dakota. I observed high, post-surgery (> 26 days) survival rate (90%) of radio tagged Brown Trout. Average gross movement of Brown Trout was greater at the improved habitat site (127 m) compared to the mink removal (31 m) site, while average home range size (i.e., stream distance) among all three sites was not significantly different indicating strong site fidelity (125 to 200 m). Brown Trout movements …

Fish Passage And Hydropower: Investigating Resource Agency Decision-Making During The Ferc Hydropower Relicensing Process, Sarah Vogel

Electronic Theses and Dissertations

Hydropower dams represent a significant challenge for the successful migration of sea-run fish, many species of which are in decline. Most hydropower dams in the United States are regulated by the Federal Energy Regulatory Commission (FERC), an independent federal agency responsible for granting 30 to 50-year licenses to projects for their continued operation. Licenses typically include conditions for the conservation of sea-run fish such as fish passage construction, operational changes, monitoring of effectiveness, and other mitigative conditions. While FERC remains the primary authority in licensing, the current regulatory framework stipulates input from other federal and state resource and regulatory agencies, …

Effect Of Water Velocity And Temperature On Energy Use, Behavior, And Mortality Of Pallid Sturgeon Scaphirhynchus Albus Larvae, Joseph Thomas Mrnak

Electronic Theses and Dissertations

Pallid Sturgeon Scaphirhynchus albus are a federally endangered species endemic to the Missouri River basin. Natural reproduction has been limited for decades and a recruitment bottleneck is hypothesized to occur during the larval stage of development. Understanding factors that affect survival of Pallid Sturgeon larvae is key given their critical status and ongoing recovery efforts. In this study, I evaluated the effects of water velocity and temperature on energy use, behavior, and mortality of endogenously feeding Pallid Sturgeon larvae (< 25 mm TL). In the first experiment, I examined the effect of water velocity (0 – 8.3 cm s⁻¹) on larval growth, energy density, swimming activity, and mortality. Larval growth rate at 16.3 °C was similar across …

Social Conflict On The Seas: Links Between Overfishing-Induced Marine Fish Stock Declines And Forced Labor Slavery, Jessica L. Sparks

Electronic Theses and Dissertations

Despite media attention detailing labor abuses in fisheries, social-ecological systems research has largely failed to consider whether fish stock declines could be contributing to increases in forced labor slavery. Empirical fisheries data suggests, though not a ubiquitous response to declining stocks, many vessels will fish longer, farther from shore, and deeper in waters to maintain yields. This effort intensification increases production costs, and Brashares et al. (2014), consistent with slavery theory, posited cheap and/or unpaid labor as an approach to offset increasing costs and continue harvesting fish species at a rate otherwise cost-prohibitive.

Using fuzzy cognitive mapping - a participatory, …

Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott

Electronic Theses and Dissertations

Effective management of freshwater fishes requires a mechanistic understanding of the drivers of assemblage composition; in other words, what determines who is where and when. Stream fish assemblages are potentially influenced by environmental factors that act on multiple spatiotemporal scales, but the relative influence of these drivers may vary between geophysically distinct regions. This study sought to determine the patterns and drivers of fish taxonomic and functional assemblage composition in the coastal plain, a region possessing unique hydrologies, faunas, and physiochemical conditions. I addressed this goal using two complementary chapters, both of which utilized environmental and biotic data collected from …

Sea Lamprey (Petromyzon Marinus) As A Functional Link Between Marine And Freshwater Ecosystems, Daniel M. Weaver

Electronic Theses and Dissertations

Anadromous sea lamprey Petromyzon marinus are native to Atlantic coastal systems and serve as a functional link between marine and freshwater ecosystems. Sea lamprey spend 1–2 years in the ocean parasitizing marine vertebrates before migrating into freshwaters during the spring to spawn. There they construct nests, spawn, then die shortly afterwards. Larvae hatch, bury into fine sediments and reside in streams for generally 6–8 years, but up to 14. Larvae then undergo metamorphosis, a non-feeding period characterized by a series of physical and physiological changes. The juveniles (macropthalmia) then migrate to the ocean to begin the parasitic juvenile phase.

Historically, …

An Evaluation Of Nitrogen Supplementation And Processed Soy Fractions On The Performance Of Cultured Fishes, Brandon M. White

Electronic Theses and Dissertations

World population growth has resulted in an increased demand for a sustainable food supply. This rapid growth coupled with an increased per capita consumption of seafood, has resulted in many of the world’s marine fisheries being over-exploited in an effort to meet the global demand for seafood. Aquaculture has attempted to fill the supply and demand gap created by the dwindling supply of fish in the world’s oceans. Fishmeal (FM) has traditionally been the primary protein ingredient in aquafeeds fed to farm-raised fish, however its unstable supply and increasing price have driven researchers to identify alternative protein sources. Soybean meal …

Effects Of A Large-Scale Habitat Enhancement Project On Largemouth Bass Behavior, Feeding, And Growth In Grand Lake, Texas, Chance Kirkeeng

Electronic Theses and Dissertations

The quality of habitat, or the environment suitable for an organism to survive and reproduce, is often described by the type of features present and the quantity and condition of such features. Habitats in many ecosystems are declining and the loss of important habitats likely affects the success of organisms reliant upon those features. Habitats in reservoir ecosystems are especially at risk because of aging processes that are degrading reservoir habitats at faster rates than habitats in other ecosystems. Habitat enhancement projects are one tool used to combat the effects of aging reservoirs but the benefits of these management actions …

Development And Application Of A Fish-Based Index Of Biotic Integrity For Lakes In Eastern South Dakota, Daniel T. Nelson

Electronic Theses and Dissertations

The Index of Biotic Integrity (IBI) was developed to summarize the impact of watershed and water quality degradation to biotic communities and help to provide a more complete picture of water quality changes that are not captured in traditional physical and chemical measurements. In 2014, nearly 15% of South Dakota lakes did not meet their designated beneficial uses based on water quality measures but the impacts to the fish communities are unknown. The goal of this study was to develop a fish-based IBI for eastern South Dakota lakes by addressing three specific objectives:
1) Determine whether an IBI could be …

Invertebrate Prey Selectivity Of Channel Catfish (Ictalurus Punctatus) In Western South Dakota Prairie Streams, Erin D. Peterson

Electronic Theses and Dissertations

Benthic invertebrates are an important resource for aquatic consumers and should be considered in management of sportfish populations as a factor influencing fishery health. Our study seeks to draw a relationship between invertebrate prey availability and the Channel Catfish Ictalurus punctatus fishery of western South Dakota through diet analysis, but invertebrate surveys in the area have not focused on invertebrates as a prey source. Our objectives were to characterize patterns in availability of the invertebrate prey base in five major river basins, and to evaluate the effects of availability on Channel Catfish prey selectivity and condition. Invertebrates were collected at …

Understanding The Impact Of Commercial Harvest On White Suckers (Catostomus Commersonii) In Maine, Megan A. Begley

Electronic Theses and Dissertations

The State of Maine issues an unlimited number of commercial permits for the harvest of White Suckers Catostomus commersonii in Maine’s inland waters. The fishery provides a necessary source of fresh lobster Homarus americanus bait to coastal communities at a time when other bait sources are scarce. The impacts of the increasing number of permits and subsequent numbers of fishermen on the white sucker population is unknown. The Maine Department on Inland Fisheries and Wildlife (MDIFW) has closed a number of waters due to concerns that overfishing and incidental catch of other fish species may occur.

In Chapter 1, we …

Interannual Variability In American Lobster Settlement: Correlations With Sea Surface Temperature, Wind Stress And River Discharge, Mahima Jaini

Electronic Theses and Dissertations

Recruitment to benthic marine populations is fundamentally a biophysical problem. The American Lobster Settlement Index is an annual diver-based survey of the young-of-year American lobsters (Homarus americanus) found in inshore nurseries in New England, USA and Atlantic Canada at the end of the postlarval settlement season. The considerable interannual variability in the settlement index suggests that environmental factors play an important role in regulating planktonic larval supply and transport. In this study, I focused on the longest settlement time series from three oceanographically contrasting regions: Midcoast Maine, coastal Rhode Island and the lower Bay of Fundy. Sampling in these regions …

An Investigation Of The Cumulative Impacts Of Shrimp Trawling On Mud Bottom Fishing Grounds In The Gulf Of Maine: Effects On Habitat And Macrofaunal Community Structure, Anne W. Simpson

Electronic Theses and Dissertations

Despite the widespread occurrence of trawl fisheries on mud-bottoms, there is limited knowledge concerning the effects of trawling induced disturbance on these habitats and their resident macrofaunal communities. I investigated the cumulative impacts of seasonal commercial shrimp trawling on infaunal habitat and macrofaunal community structure on two mud-bottom fishing grounds in the Gulf of Maine from June 2000 - December 2001. One fishing ground located near the Outer Pumpkin Ledges (Pumpkin) experienced trawling activity during the 2000-2001 fishing season. In contrast, the other fishing ground near Monhegan Island was not trawled during the same period because shrimp abundances were low. …

Resilience Of Green Sea Urchin (Strongylocentrotus Droebachiensis) Populations Following Fishing Mortality: Marine Protected Areas, Alternate Stable States, And Larval Ecology, John Vavrinec Iii

Electronic Theses and Dissertations

The green sea urchin Strongylocentrotus droebachiensis has been aggressively fished in Maine since 1986 resulting in severe population declines throughout portions of the state. This research used Marine Protected Areas (MPAs) to evaluate the potential for recovery in depleted sea urchin populations. It was necessary to not only look at the direct impacts of the MPAs, but also at larval transport / supply and community interactions to gain a better understanding of the system. We found that MPAs in the Gulf of ~a!ne were of varied utility to restoring depleted sea urchin populations depending on location and community structure. MPAs …

Modeling The Role Of No-Take Marine Reserves In Fisheries Management, Deidre F. Gilbert

Electronic Theses and Dissertations

In recent years there has been increasing interest in the potential of no-take marine reserves to benefit fisheries management. Scientific reviews have shown that reserves often lead to substantial increases in the density, biomass, size and diversity of marine fishes inside their boundaries. However, little empirical work has been done to determine the effect of reserves on the fisheries outside their boundaries, such as potential changes in yield, size of fleet, or variability in catch. In order to explore the interaction between the biological growth and dispersion processes of the harvested stock and the changing economic incentives of harvesters created …

A Pilot Study To Test Ventless Traps As A Means To Quantify Populations Of The American Lobster (Homarus Americanus), Carin Louise Poeschel

Electronic Theses and Dissertations

The American lobster, Homarus americanus, is Maine's most valuable marine fishery. The state of Maine has an economic interest in the protection of this resource. The health of this industry depends on effective management for sustainability. However, there is little quantitative information on American lobsters less than harvestable size. A study was conducted to evaluate the utility of traps modified to catch sublegal lobsters. With the aid of fishernlen fiom six of the eight Maine coastal counties over a four-month time period (July through October, 2000), data were recorded to compare catch rates in experimental traps with no escape vents …

Marine Protected Areas In The Gulf Of Maine: Policy For A Common Resource, Carolyn F. Skinder

Electronic Theses and Dissertations

In the wake of 25 years of unsuccessful single-fisheries management in the Gulf of Maine, there has been growing support for reform. Ecosystem management has been proposed as one alternative, but the information needed to manage whole ecosystems is greatly lacking. Implementing fully-protected marine protected areas (MPAs) is one way to preserve habitat while at the same time acquiring data for future ecosystem management. Under the current institutional arrangement in the Gulf, engineering agreement for MPAs is difficult due to the differing goals of varied user groups. The situation is reflective of a common property resource problem in that there …

Chemosensory-Mediated Deposit Feeding In The Spionid Polychaete Dipolydora Quadrilobata., Timothy J. Riordan Jr.

Electronic Theses and Dissertations

Deposit feeding organisms live and feed in marine soft-sediment habitats. This sediment makes up a majority of the material ingested by deposit feeders and contains a variety of edible material that may constitute their principal nutrient source. However, the specific components that are assimilated by these organisms, and the strategies they employ to efficiently collect those components, remain unclear. Sensory interactions between an organism and its surrounding environment typically play an important role in helping the organism detect and locate potential food. Accordingly, chemical sensing by deposit feeders is most likely involved in feeding, yet few specifics about this role …