Ecology and Evolutionary Biology Commons^™

Forecasting The Spread And Invasive Potential Of Apple Snails (Pomacea Spp.) In Florida, Stephanie A. Reilly

HCNSO Student Theses and Dissertations

Forecasting the potential range of invasive species is a critical component for risk assessment, monitoring, and management. However, many of these invasive species are not yet at equilibrium which can be problematic for many modelling approaches. Using the climate matching method, MaxEnt, a series of species distribution models (SDMs) and risk analysis maps were created for select apple snail species in Florida: Pomacea canaliculata, P. diffusa, and P. maculata. Apple snails, freshwater gastropods in the family Ampullariidae, are native to South America and were introduced to the United States via the pet trade approximately 40 years ago. …

Lake Sturgeon (Acipenser Fulvescens) Trophic Position And Movement Patterns In The Lower Niagara River, Ny, Eric Bruestle

Great Lakes Center Masters Theses

Lake sturgeon Acipenser fulvescens were once widely distributed throughout the Laurentian Great Lakes. However, widespread overharvest and habitat degradation has diminished their numbers. The lower Niagara River, NY contains one of the few remaining recovering populations of lake sturgeon in New York State. The goal of this study was to characterize the trophic position of lake sturgeon in the context of an invasive species dominated food web and to describe their movement patterns and residency within the lower Niagara River. Stomach content analysis and stable nitrogen (δ¹⁵N) and carbon (δ¹³C) isotope analysis of tissue was used …

Modelling Walleye Population And Its Cannibalism Effect, Quan Zhou

Electronic Thesis and Dissertation Repository

Walleye is a very common recreational fish in Canada with a strong cannibalism tendency, such that walleyes with larger sizes will consume their smaller counterparts when food sources are limited or a surplus of adults is present. Cannibalism may be a factor promoting population oscillation. As fish reach a certain age or biological stage (i.e. biological maturity), the number of fish achieving that stage is known as fish recruitment. The objective of this thesis is to model the walleye population with its recruitment and cannibalism effect. A matrix population model has been introduced to characterize the walleye population into three …

Examining The Relationship Between Mesohabitats And Freshwater Mussels In An East Texas River, Andrew R. Glen

Biology Theses

North America is home to 302 unionoid species, with approximately 53 occurring in Texas, and are considered one of the most imperiled group of organisms in North America. Several hypotheses have been proposed to explain the spatial distribution of mussels within a stream reach, but only certain hydraulic characteristics appear to be correlated with their distribution. Emerging evidence indicates that freshwater mussels may use flow refugia to remain embedded during high flow events. As the use of hydraulic variables to characterize mussel habitat becomes more widespread, it may be useful to implement sampling that captures these measures. One option may …

A Hemimysis Driven Novel Ecosystem At A Modified Boulder Breakwall, Eric John Geisthardt

Theses and Dissertations

The US Army Corps of Engineers (USACE) is mandated to maintain and repair aging breakwall structures in all commercial ports on the Great Lakes. In May of 2014, the construction of Milwaukee Harbor USACE “green” breakwall (GBW) reconciliation created complex rocky aquatic habitat by depositing cobble-sized stone as a veneer over standard 6-10 ton boulders, thus creating “control” (boulder) and “treatment” (cobble) habitats. The breakwall is home to a prolific population of Hemimysis anomala, the introduced Ponto-Caspian mysid, which is significantly more abundant on cobble versus boulders (p<0.05, using a novel trap for Hemimysis). Fish and forage communities were sampled in 2015 and 2016 using a combination of experimental and micromesh gill nets, night scuba diving surveys, and a novel Hemimysis trap. This nearshore lithophilic mysid appears to provide a significant new seasonal food resource in the Milwaukee Harbor for pelagic prey fishes during inshore spawning migrations and upwelling events. Alewife (Alosa pseudoharengus) and rainbow smelt (Osmerus mordax) fed heavily on Hemimysis with some individuals consuming hundreds of mysids. Night scuba diving surveys and gill netting confirmed that rainbow smelt preferred to forage on the cobble section (p<0.05), and also consumed more Hemimysis there than they did at the control breakwall site (p<0.05). Hemimysis were also the primary food item consumed by nearshore game fishes such as YOY yellow perch (Perca flavescens), YOY largemouth bass (Micropterus salmoides), and juvenile rock bass (Ambloplites rupestris) caught at the breakwall. This study provides the first documented evidence that where abundant in the Laurentian Great Lakes, Hemimysis do have the ability to significantly impact local food webs and drive the feeding ecology of both pelagic transient and nearshore resident fishes.

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, …

The Effect Of "Casitas" On Lobster Biology And Fishery Sustainability In The Bahamas, Lester George Gittens

Biological Sciences Theses & Dissertations

“Casitas” (artificial table-like structures) are a commercial fishing gear used to harvest Caribbean spiny lobster (Panulirus argus) in the Caribbean and in The Bahamas, where lobster is the most valuable fishery. Yet, casitas are largely unregulated in The Bahamas and they may threaten fishery sustainability through alteration of lobster growth, disease, or mortality rates and due to insufficient information concerning their number and location. Focusing on the lobster fishery in The Bahamas, my objectives were to: (1) investigate the mortality, growth, and susceptibility to disease of lobsters collected in casitas compared to wooden traps and those living in …

Measuring Fertilization In Populations Of Sea Scallop (Placopecten Magellanicus): Developing And Testing Methods In The Laboratory And Field, Skylar Bayer

Electronic Theses and Dissertations

Most marine organisms are broadcast spawners, releasing their sperm and eggs into the water column. Methods of measuring in situ fertilization have proven successful with a few model species, which are reviewed in my introductory chapter. However, many commercially exploited species, such as the sea scallop Placopecten magellanicus, have been neglected. Sea scallop populations have greatly increased from fishing closures, but the mechanism behind this response is uncertain, particularly in regard to fertilization. In this dissertation I developed a methodology of measuring fertilization success and spawning events of P. magellanicus, tested it in laboratory and field settings, and …

Evaluating Habitat-Based Niche Requirements And Potential Recruitment Bottlenecks For Imperiled Bluehead Sucker (Catostomus Discobolus), Bryan C. Maloney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Changes to rivers that alter physical and thermal habitat may cause fish population abundance to decline, due to fewer individuals maturing and entering the adult population. The Weber River has become highly degraded with many dams and diversions altering fish habitat, river volume, velocity, and temperature, and limiting movement between reaches. Bluehead suckers (Catostomus discobolus) occupy only 47% of their historical range and the genetically-distinct Weber River (northern UT) population is declining and contains few young, juvenile fish. My objectives were to determine whether spawning and rearing habitat available in the Weber River may be limiting bluehead sucker …

Population Structure, Connectivity, And Phylogeography Of Two Balistidae With High Potential For Larval Dispersal: Balistes Capriscus And Balistes Vetula, Luca Antoni

Dissertations

The gray triggerfish (Balistes capriscus) and the queen triggerfish (Balistes vetula) are two exploited reef fish distributed in tropical and temperate shelf waters of the Atlantic Ocean and the Mediterranean Sea. Both species are highly sedentary as adults but disperse pelagic larvae for extended periods of time potentially allowing connectivity across long distances under the action of oceanic currents. In this work population structure, phylogeography, and migration patterns were examined in the two species and contrasted with predictions of larval transport based on surface circulation data. A total of 1,017 gray triggerfish from twelve sampling localities …

Determination Of Metal Concentrations In Sediments Of Big Walnut Creek, Hayley Quinn, Joan M. Esson, Kierra M. Lathrop, Michael A. Hoggarth, Kevin Svitana, Nathan Hess

Undergraduate Distinction Papers

The freshwater mussel populations in the lower stretch of Big Walnut Creek in central Ohio have been found to vary along the run of the creek with the lowest population of mussels in the middle stretch. One possible cause for the decline is the presence of contaminants in the sediments of the creek. In this study, nine Sites along the creek were examined. At each Site, sediment samples from a pool region and two quadrants from where mussels were also studied (the area of interest) were collected, along with pseudo feces, which is the waste mussels produce as they filter …

A Reexamination The Freshwater Mussels (Family Unionidae) In Lower Big Walnut Creek, Kierra M. Lathrop

Undergraduate Distinction Papers

Freshwater mussels (family Unionidae) have become increasingly rare as the threats to water quality, habitat quality, and other aquatic animals, which the mussels depend on, have increased. The absence of mussels can provide evidence that one of these factors is insufficient. Lower Big Walnut Creek (BWC) is known to support a diverse community of mussels but they are unevenly distributed throughout the creek with abundance, density, and richness being high in the upper section, very low in the midsection, and intermediate in the lower section. It has been suggested water quality nor symbiotic fish host communities are responsible for this …

The Mixed Source Chinook Salmon Fishery In Lake Huron: A Comparison Of Spawning And Foraging Habitat Use By Naturalized And Hatchery Fish, Stephen A.C. Marklevitz

Electronic Thesis and Dissertation Repository

Chinook salmon (Oncorhynchus tshawytscha) were introduced into the Great Lakes to restore top-down control of the food web and create new recreational fisheries. Soon after introduction, naturalized spawning populations became established, and with continued stocking of hatchery fish, created a mixed source fishery. My research provides new ecological information about the contributions of naturalized fish to the mixed source Chinook salmon fishery in Lake Huron. I examined spawning and foraging habitat use by naturalized and hatchery Chinook salmon using multiple methods to identify sources of individual fish (external tags, hatchery fin clips, and otolith microchemistry). In the Sydenham …

Analysis Of Bioaccumulation Of Selenium Diets In Brook Trout (Salvelnius Fontinalis), Kyle Aaron Tasker

Theses, Dissertations and Capstones

The brook trout (Salvelinus fontinalis) is facing many challenges throughout the Appalachian region, which are thought to be brought on by effects of climate change and the loss of habitat because of the disturbance from the pursuit of energy sources, namely, the mining of coal in the region. Most of the mining occurs in the central plateau and southern mountain region of West Virginia. The brook trout have historically had an expansive range covering this region and has the potential to inhabit the headwater stream systems that occur very prevalently throughout the Appalachians. In the state of West Virginia, the …

Investigating The Quantity And Types Of Microplastics In The Organic Tissue Of Oysters And Crabs In The Indian River Lagoon, Heidi Waite

Honors Undergraduate Theses

Microplastics are widespread and abundant. Few studies have examined the diversity and abundance of microplastics in wild organisms. This study determined the microplastic quantity and types in the organic tissues of the eastern oyster Crassostrea virginica and Atlantic mud crab Panopeus herbstii from the Indian River Lagoon (IRL). This study also investigated whether location affected the microplastic abundance and variety. Organisms were collected from three sites across Mosquito Lagoon in the northern IRL. Oysters were frozen after collection. Crabs were placed in containers for 5 days before freezing. The soft organic tissue was chemically digested using hydrogen peroxide, filtered, …

Juvenile Blue Crab (Callinectes Sapidus) Response To Altered Nursery Habitat, Megan Wood

Dissertations, Theses, and Masters Projects

Habitats of Chesapeake Bay have been altered due to anthropogenic impacts and climate change. Due to these human disturbances, seagrasses have been extirpated from many areas in lower Chesapeake Bay and persisting beds face future losses as water temperatures continue to rise. Further loss of seagrass habitat will negatively impact juvenile blue crabs (Callinectes sapidus) that use seagrass beds as nursery grounds. Habitat degradation allows for more successful introductions of exotic species, and the communities formed from the mixing of native and exotic species are known as emerging ecosystems. Gracilaria vermiculophylla, an exotic macroalga, may be an emerging nursery habitat …

Ecosystem Services Of Restored Oyster Reefs In A Chesapeake Bay Tributary: Abundance And Foraging Of Estuarine Fishes, Bruce William Pfirrmann

Dissertations, Theses, and Masters Projects

Oyster reef restoration may enhance the production of ecologically or economically important fish species, an ecosystem service, by providing refuge and foraging habitat. Predicting the effects of oyster habitat restoration on fisheries production in Chesapeake Bay requires a better understanding of fish habitat use, trophic dynamics, and the processes leading to production on a habitat-scale. The objective of this thesis was to evaluate the influence of restored subtidal oyster reefs on the abundance and foraging patterns of mobile estuarine fishes. Specifically, I compared the 1) abundance, 2) stomach fullness, 3) diet composition, and 4) daily consumption rate of fishes collected …

Interactive Effects Of Flow Regime, Climate Change, And Angler Harvest On Smallmouth Bass At The Southern Range Extent, Christopher Middaugh

Graduate Theses and Dissertations

The Ozark-Ouachita Interior Highlands of Arkansas, Oklahoma, and Missouri are the southern extent of native Smallmouth Bass Micropterus dolomieu range. Smallmouth Bass are an important species economically and ecologically, but it is unknown how climate change may affect them in this region and in particular how Smallmouth Bass may be affected differently across streams from various flow regimes. Here I present three projects investigating how climate change, flow regime, and angler harvest may interact to affect Smallmouth Bass over the coming century. I first modeled present and future water temperatures and calculated growth rate potential for Smallmouth Bass from streams …

Impact Of The Parasitic Nematode Anguillicoloides Crassus On American Eels (Anguilla Rostrata) In Chesapeake Bay, Zoemma Taudel Warshafsky

Dissertations, Theses, and Masters Projects

American eels are infected by the introduced parasitic nematode, Anguillicoloides crassus, which can cause significant damage to their swimbladders. Despite the high prevalence and severe damage caused by A. crassus, the population level effects on American eels are not well understood. The prevalence and swimbladder damage in young glass eels and elvers are relatively unstudied, despite the potential for this parasite to cause tissue damage. Additionally, the effects of environmental, temporal, and spatial variables have been debated in previous studies without consensus. Also, the potential for eels to recover from infection and tissue damage has been speculated but not definitively …

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 …

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 …

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 …

The Status Of Snapping Turtles (Chelydra Serpentina) In Virginia: Population Viability, Demography, Regulatory Analysis, And Conservation, Benjamin C. Colteaux

Theses and Dissertations

Snapping turtles (Chelydra serpentina) are being harvested in unprecedented numbers in the United States (US) to meet the needs of international markets. Over three million live snapping turtles from farm and wild caught stock were exported from the US to Asia in 2012-14 alone. In the Commonwealth of Virginia, records indicate that 29,860 snapping turtles were commercially harvested between 2000 and 2015. Size limits are often used to regulate harvest pressure in snapping turtles and other game species. I analyzed the historic harvest of eleven US states to test the efficacy of minimum-size limit regulations at reducing commercial …

Spatiotemporal Abundance Patterns And Ecological Drivers Of A Nearshore U.S. Atlantic Fish And Invertebrate Assemblage, Mark A. Stratton

Dissertations, Theses, and Masters Projects

Taking an ecosystem approach to fisheries requires the consideration of relevant ecological processes within research and assessment frameworks. Processes affecting ecosystem productivity can be categorized as biophysical (climate variability, primary production), exploitative (fishing), or trophodynamic (food web interactions). This dissertation incorporates these three governing processes to characterize spatiotemporal diversity and population abundance trends for multiple demersal fish and invertebrate species that inhabit the nearshore zone (15-30 ft. depth) along portions of the U.S. Atlantic east coast.

Two large marine ecosystems (LMEs) encompass the U.S. East coast – the Southeast and Northeast U.S. Continental Shelf LMEs. The level of connectivity within …

Juvenile Blue Crab Survival In Nursery Habitats: Predator Identification And Predation Impacts In Chesapeake Bay, Amanda Marie Bromilow

Dissertations, Theses, and Masters Projects

Predator populations can have significant impacts on prey recruitment success and prey population dynamics through consumption. Young, inexperienced prey are often most vulnerable to predation due to their small size and limited evasion capabilities. to reduce the risk of predation, new recruits and young juveniles typically settle in structured nursery habitats, such as seagrass beds, which promote higher survival by acting as refuges from predators. Thus, successful recruitment to the adult portion of the population is often dependent on the availability of suitable nursery habitat. In this thesis, I used field tethering experiments and gut content analyses to assess the …