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Full-Text Articles in Fresh Water Studies

Nekton Utilization Of Intertidal Fringing Salt Marsh And Revetment Hardened Shorelines, Robert A. Carroll Jan 2002

Nekton Utilization Of Intertidal Fringing Salt Marsh And Revetment Hardened Shorelines, Robert A. Carroll

Dissertations, Theses, and Masters Projects

No abstract provided.


Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown Jan 2001

Molecular Characterization Of Cultured Perkinsus Marinus Isolates, Gwynne D. Brown

Dissertations, Theses, and Masters Projects

Perkinsus marinus is the causative agent of the oyster disease Dermo in the eastern oyster, Crassostrea virginica. In vitro propagation of the parasite has led to the establishment of multiple isolates by several investigators. Little work, however, has been done to characterize different isolates. In this study multiple isolates were examined for genetic and biochemical diversity. at two loci, the ITS region and the ATAN region, there was as much intra-isolate genetic variation among DNA sequences of some isolates as there was inter-isolate variation. Variation was also observed at a third loci, a subtilisin-like serine protease gene. This is the …


The Impact Of Marine Reserves On Exploited Species With Complex Life Histories: A Modeling Study Using The Caribbean Spiny Lobster In Exuma Sound, Bahamas, William T. Stockhausen Jan 2001

The Impact Of Marine Reserves On Exploited Species With Complex Life Histories: A Modeling Study Using The Caribbean Spiny Lobster In Exuma Sound, Bahamas, William T. Stockhausen

Dissertations, Theses, and Masters Projects

Most benthic invertebrates and reef-associated fish undergo a dispersive, planktonic larval stage prior to settlement and metamorphosis into the juvenile and adult stages. In some species, settlement may be decoupled from adult abundance at local spatial scales if hydrodynamic conditions or larval behavior do not promote local retention. Similarly, spatial variability in postsettlement mortality or secondary dispersal by juveniles and adults may decouple spatial patterns of adult abundance from those of settlement. as a consequence, spatial patterns of settlement and adult abundance may be functionally related in a complex fashion. Whether biotic/environmental factors control spatial patterns of abundance may have …


The Human Factor In Size Selectivity In The Sea Scallop, Placopecten Magellanicus Fishery, Arman O. Kaltayev Jan 2000

The Human Factor In Size Selectivity In The Sea Scallop, Placopecten Magellanicus Fishery, Arman O. Kaltayev

Dissertations, Theses, and Masters Projects

No abstract provided.


Synoptic Scale Climatic Forcing Of Multispecies Fish Recruitment Patterns In Chesapeake Bay, Robert J. Wood Jan 2000

Synoptic Scale Climatic Forcing Of Multispecies Fish Recruitment Patterns In Chesapeake Bay, Robert J. Wood

Dissertations, Theses, and Masters Projects

Five fishery independent data sets were used to investigate multispecies fish recruitment patterns in Chesapeake Bay (1966--1997). Despite differences in sampling gear, sampled habitat, collection methods, and sampling sites, the strongest multispecies recruitment patterns within each data set (revealed by separate principal components analyses) depict a negative relationship between recruitment of spring spawning anadromous fishes and fall-winter continental shelf spawning species. This pattern dominates both low and high frequency components of the multispecies data. Because these two species groups utilize freshwater and oligohaline reaches of the Bay and its tributaries as springtime nursery areas, this Chesapeake Bay Anadromous-Shelf Spawner (CBASS) …


Sensory Development In Settlement-Stage Larvae Of Caribbean Labrids And Scarids: A Comparative Study With Implications For Ecomorphology And Life History Strategies, Monica R. Lara Jan 1999

Sensory Development In Settlement-Stage Larvae Of Caribbean Labrids And Scarids: A Comparative Study With Implications For Ecomorphology And Life History Strategies, Monica R. Lara

Dissertations, Theses, and Masters Projects

The sensory capabilities of settlement-stage fishes are unknown but this information is necessary to studies of larval settlement and recruitment. The morphology of the cephalic lateral line, eye and external olfactory organ of thirteen species of settlement-stage Caribbean labroids was described. Scanning electron images of the cephalic lateral line neuromasts, lateral line canals and olfactory epithelia and histological studies of the retinae and morphological measurements of visual acuity were used to assess the level of sensory development attained at settlement. The sensory capabilities of settlement-stage fishes are discussed in relation to the possible cues settlement-stage fishes may be using to …


Spatial And Temporal Distributions Of Organic Matter And Polycyclic Aromatic Hydrocarbons (Pahs) In Surface Waters Of The York River, Va Estuary, Rebecca E. Countway Jan 1999

Spatial And Temporal Distributions Of Organic Matter And Polycyclic Aromatic Hydrocarbons (Pahs) In Surface Waters Of The York River, Va Estuary, Rebecca E. Countway

Dissertations, Theses, and Masters Projects

No abstract provided.


Habitat Fragmentation In Transplanted Eelgrass (Zostera Marina) Beds: Effects On Decapods And Fish, Alfonso Vollmer Lombana Jan 1999

Habitat Fragmentation In Transplanted Eelgrass (Zostera Marina) Beds: Effects On Decapods And Fish, Alfonso Vollmer Lombana

Dissertations, Theses, and Masters Projects

No abstract provided.


Tidal Freshwater And Oligohaline Benthos: Evaluating The Development Of A Benthic Index Of Biological Integrity For Chesapeake Bay, Robyn C. Draheim Jan 1998

Tidal Freshwater And Oligohaline Benthos: Evaluating The Development Of A Benthic Index Of Biological Integrity For Chesapeake Bay, Robyn C. Draheim

Dissertations, Theses, and Masters Projects

No abstract provided.


Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford Jan 1998

Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford

Dissertations, Theses, and Masters Projects

Phylogenetic and historical biogeographic hypotheses were explored for three groups of teleost fishes that are hypothesized to share a common biogeographic track. Distributed across the eastern Pacific/eastern Atlantic (EP/EA) biogeographic track of Rosen (1975) are the Scomberomorus regalis (Scombridae), Strongylura marina (Belonidae) and Hyporhamphus unifasciatus (Hemiramphidae) species groups comprised of one eastern Atlantic; three, three and four western Atlantic; and two, two and four eastern Pacific species, respectively, for each group. In addition, two species in the Strongylura marina and Hyporhamphus unifasciatus groups, have invaded freshwater drainages of Central and South America. Each of the three species groups were found …


The Parasite Fauna Of The Wreckfish, Polyprion Americanus, In The North Atlantic Ocean: Application To Host Biology And Stock Identification, Colleen Jill Fennessy Jan 1998

The Parasite Fauna Of The Wreckfish, Polyprion Americanus, In The North Atlantic Ocean: Application To Host Biology And Stock Identification, Colleen Jill Fennessy

Dissertations, Theses, and Masters Projects

No abstract provided.


Climatologically Forced Coherence Between Diverse Juvenile Populations In The Virginia Tributaries To The Chesapeake Bay, Thomas C. Mosca Iii Jan 1997

Climatologically Forced Coherence Between Diverse Juvenile Populations In The Virginia Tributaries To The Chesapeake Bay, Thomas C. Mosca Iii

Dissertations, Theses, and Masters Projects

Long term trends in juvenile recruitment of oyster, bluecrab, and 24 species of finfish in a large temperate estuary (lower Chesapeake Bay, USA) are coherent across the three major tributaries (the Virginia rivers James, York, and Rappahannock). The driving force for these long term trends is geographically large in scale. Anomalous winters in the mid 1970's, with the warmest years on record followed immediately by the coldest, caused a severe perturbation in population dynamics. The extreme conditions caused the system to shift, with recruitment patterns following temperatures by a one year lag. Following this anomalous episode, smoothed mean winter water …


Demersal Predator Exposure To Toxic Organic Contaminants: Direct Effects Of Macrofauna In Trophic Transfer, Patrick Winfield Lay Jan 1996

Demersal Predator Exposure To Toxic Organic Contaminants: Direct Effects Of Macrofauna In Trophic Transfer, Patrick Winfield Lay

Dissertations, Theses, and Masters Projects

The bioaccumulation and metabolism of organic contaminants (PAH, PCB) by three estuarine polychaetes, Nereis succinea (Frey and Leuckart 1847), Paraprionospio pinnata (Ehlers 1901) and Polydora ligni (Webster 1879), and by the fish predator, spot (Leiostomus xanthurus Lacepede 1802), were examined in laboratory experiments. Variations in trophic transfer of these contaminants resulting from differences in prey and contaminant type were also investigated. Toxicokinetic modeling reveals that metabolism of organic contaminants by invertebrate species result in variations in uptake, metabolism and elimination rate constants. Incorporation of prey metabolism potential in kinetic models increases the latter's predictability of biota-sediment accumulation factors (BSAFs), or …


The Role Of Microbial Food Webs In Benthic-Pelagic Coupling In Freshwater And Marine Ecosystems, Adele J. Pile Jan 1996

The Role Of Microbial Food Webs In Benthic-Pelagic Coupling In Freshwater And Marine Ecosystems, Adele J. Pile

Dissertations, Theses, and Masters Projects

A majority of carbon in freshwater and marine ecosystems is in the form of ultraplankton, heterotrophic and autotrophic plankton &<&5 &\mu&m including heterotrophic bacteria, Prochlorococcus, cyanobacteria, and autotrophic eucaryotes. However, ultraplankton and subsequently microbial food webs have yet to be incorporated into models of benthic-pelagic coupling despite the preponderance of macroinvertebrates with the capacity to feed on ultraplankton. I have examined the role of microbial food webs in benthic-pelagic coupling in three ecosystems: Lake Baikal, Siberia, Russia; Gulf of Maine, Northwest Atlantic Ocean; and Conch Reef, Florida Keys, USA. Using sponges as a model organism and in situ measurements, I have quantified (1) suspension feeding on ultraplankton and (2) release of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) resulting in direct evidence that benthic macroinvertebrates do occupy the level of primary consumer within the microbial food web. Dual-beam flow cytometry was employed to quantified sponge suspension feeding on five types of ultraplankton: heterotrophic bacteria, Synechococcus-type cyanobacteria, autotrophic picoplankton &<&3 &\mu&m, autotrophic eucaryotes 3-10 &\mu&m, and in marine ecosystems Prochlorococcus. Grazing by the freshwater sponges Baikalospongia intermedia and B. bacilliferia and the boreal marine sponge, Mycale lingua, was unselective for all types of ultraplankton with efficiencies ranging from 63-99%. This is the first time that grazing on Synechococcus-type cyanobacteria and Prochlorococcus by macroinvertebrates has been quantified in freshwater and marine ecosystems. Conversely, the coral reef sponges Ircinia felix and I. strobilina release significant amounts of DIN and DIP as a result of grazing on procaryotic plankton. Using a general model for organism-mediated fluxes, it is conservatively estimated that through active suspension feeding sponges in Lake Baikal retain 1.97 g C day&\sp{lcub}-1{rcub}& m&\sp{lcub}-2{rcub}& and M. lingua retains 29 mg C day&\sp{lcub}-1{rcub}& m&\sp{lcub}-2{rcub}& while at Conch Reef sponges released 204 &\mu&mol DIN day&\sp{lcub}-1{rcub}& m&\sp{lcub}-2{rcub}& and 48 &\mu&mol DIP day&\sp{lcub}-1{rcub}& m&\sp{lcub}-2{rcub}&. A majority of the carbon retained at all three locations was from procaryotic cell types suggesting that ultraplankton are an important overlooked component of benthic-pelagic coupling.


Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman Jan 1996

Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman

Dissertations, Theses, and Masters Projects

No abstract provided.


The Influence Of Location, Seagrass Species And Water Depth On The Settlement And Distribution Of Early Stage Blue Crabs, Renee A. Pardieck Jan 1996

The Influence Of Location, Seagrass Species And Water Depth On The Settlement And Distribution Of Early Stage Blue Crabs, Renee A. Pardieck

Dissertations, Theses, and Masters Projects

No abstract provided.


The Role Of Epibenthic Predators In Structuring Marine Soft-Bottom Communities Along An Estuarine Gradient, Rochelle D. Seitz Jan 1996

The Role Of Epibenthic Predators In Structuring Marine Soft-Bottom Communities Along An Estuarine Gradient, Rochelle D. Seitz

Dissertations, Theses, and Masters Projects

A unifying theory of community regulation in soft-bottom systems remains elusive, despite extensive field studies on factors controlling community structure. Here, I have (1) reviewed models of community regulation, (2) examined the role of predation in controlling benthic diversity along a salinity gradient, (3) examined effects of predation upon an abundant bivalve, Macoma balthica, and (4) revised a model of community regulation in an estuarine soft-bottom system. The Menge and Sutherland (MS) "consumer stress model" posits that consumers feed ineffectively in harsh environments, and the importance of physical disturbance, competition and predation varies with recruitment, environmental conditions, and trophic position. …


Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina Jan 1995

Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina

Dissertations, Theses, and Masters Projects

No abstract provided.


Crassostrea Virginica On Constructed Intertidal Oyster Reefs: The Effects Of Tidal Height And Substrate Level On Settlement, Growth, And Mortality, Ian K. Bartol Jan 1995

Crassostrea Virginica On Constructed Intertidal Oyster Reefs: The Effects Of Tidal Height And Substrate Level On Settlement, Growth, And Mortality, Ian K. Bartol

Dissertations, Theses, and Masters Projects

No abstract provided.


Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii Jan 1995

Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii

Dissertations, Theses, and Masters Projects

During spring 1990 and 1991, ichthyoplankton surveys were conducted in lower Chesapeake Bay to estimate seasonal egg production, population biomass and the impact of predation by gelatinous zooplankton on early life stages of black drum, Pogonias cromis. Rearing experiments indicated that at least three species of sciaenid (silver perch, Bairdiella chrysoura; weakfish, Cynoscion regalis and P. cromis) were spawning in the survey area during both years. Specific identification of eggs based on previously published ranges of outside egg diameter (OED) were not reliable due to considerable overlap in diameter distributions. Analysis of weekly OED frequency revealed the presence of three …


Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik Jan 1995

Nutrition And Feeding In Striped Bass Morone Saxatilis Larvae: Lipid And Fatty Acid Requirements And Microencapsulated Diets, Sureyya Ozkizilcik

Dissertations, Theses, and Masters Projects

There has been a growing interest in the commercial aquaculture of striped bass, Morone saxatilis. Little is known, however, about the nutritional requirements and feeding physiology of striped bass larvae. The objectives of this study were (a) to evaluate the efficiency of the live food enrichment techniques in studying the nutritional requirements for polyunsaturated fatty acids (PUFA), phospholipids and free amino acids, (b) to determine the ontogenetic changes of lipolytic enzymes, and (c) to develop a microencapsulated diet for striped bass larvae as full or partial replacement of live food. Three enrichment techniques, namely, microencapsulated fish oil, yeast/fish oil emulsion …


In Vitro And In Vivo Effects Of Chemotherapeutants On The Oyster Parasite, Perkinsus Marinus, Gustavo W. Calvo Jan 1994

In Vitro And In Vivo Effects Of Chemotherapeutants On The Oyster Parasite, Perkinsus Marinus, Gustavo W. Calvo

Dissertations, Theses, and Masters Projects

To investigate the potential of chemotherapeutants to control the oyster pathogen Perkinsus marinus, anticoccidial and antifungal compounds were tested in vitro on infected hemolymph and cultured P. marinus cells and in vivo on infected oysters. In addition, acute toxicity to oysters was determined for six anticoccidials. In vitro experiments with infected hemolymph consisted of 24 h exposure of 0.2 mL hemolymph aliquots to concentrations ranging from 100 mg/L to 0.01 mg/L of amphotericin-B, amprolium, arprinocid, cycloheximide, lasalocid, malachite green, monensin, sulfadimethoxine, and a potentiated sulfadimethoxine, followed by incubation in fluid thioglycollate medium (FTM) to determine prezoosporangia abundance. Lasalocid, malachite green, …


Size-Specific Fecundity Of The Sea Scallop, Placopecten Magellanicus, During One Spawning Period In The Mid-Atlantic Resource Area, Ryan B. Carnegie Jan 1994

Size-Specific Fecundity Of The Sea Scallop, Placopecten Magellanicus, During One Spawning Period In The Mid-Atlantic Resource Area, Ryan B. Carnegie

Dissertations, Theses, and Masters Projects

No abstract provided.


A Gis Spatial Analysis Of The Potential Conflict Between Submerged Aquatic Vegetation Management And The Development Of Shellfish Aquaculture In The Lower Chesapeake Bay, Laura Ann Grignano Jan 1994

A Gis Spatial Analysis Of The Potential Conflict Between Submerged Aquatic Vegetation Management And The Development Of Shellfish Aquaculture In The Lower Chesapeake Bay, Laura Ann Grignano

Dissertations, Theses, and Masters Projects

No abstract provided.


Mechanisms Of Larval Spot Transport And Recruitment To The Chesapeake Bay, Deborah A. Bodolus Jan 1994

Mechanisms Of Larval Spot Transport And Recruitment To The Chesapeake Bay, Deborah A. Bodolus

Dissertations, Theses, and Masters Projects

The spot (Leiostomus xanthurus) is an important commercial and recreational species in Virginia. Recruitment of juveniles to the Bay is characterized by large interannual fluctuations, that can be explained by the sequence and direction of wind during various phases of the early life history. An environmentally-modified Ricker stock-recruitment curve was developed incorporating the southeasterly winds in November-December, the southerly winds in January-March, and the westerly winds in April-May. This model explained 81% of the variation and closely paralleled the VIMS Juvenile Spot Index. Spot from the Chesapeake Bay migrate south in fall to spawn near or south of Cape Hatteras. …


Predation On Juvenile Blue Crabs, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay: Patterns, Predators, And Potential Impacts, Kirt E. Moody Jan 1994

Predation On Juvenile Blue Crabs, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay: Patterns, Predators, And Potential Impacts, Kirt E. Moody

Dissertations, Theses, and Masters Projects

Various investigations of the population dynamics of blue crabs in Chesapeake Bay indicate that predator-induced mortality in the juvenile phase may determine year-class strength. In a tethering study, which spanned three seasons in shallow-water habitats of the lower York River, daily mortality rates of juvenile crabs were measured across three variables: crab size (30-70 mm carapace width), habitat type (seagrass, mud, and sand), and month (May-November). Vulnerability to predation was consistently lower for larger crabs, approaching a size refuge from predation at approximately 90 mm carapace width. Predation was most intense in unvegetated sand habitats, and significantly lower in seagrass …


Gill Surface Area In Relation To Growth Rates And Maximum Size In Sharks, David Noboru Hata Jan 1993

Gill Surface Area In Relation To Growth Rates And Maximum Size In Sharks, David Noboru Hata

Dissertations, Theses, and Masters Projects

The most commonly used equation to describe size at age in fishes is the von Bertalanffy equation (VBE), which assumes that growth rate is based on the balance of anabolic and catabolic processes: dW/dt = HW&\sp{lcub}\rm d{rcub}&-kW&\sp{lcub}\rm m{rcub}&. Anabolism, HW&\sp{lcub}\rm d{rcub}&, is considered proportional to gill surface area (A = rW&\sp{lcub}\rm d{rcub}&), and a "generalized" VBE (GVBE) has been previously determined: L&\sb{lcub}\rm t{rcub}& = L&\sb\infty&(1-exp(-KD(t-t&\sb{lcub}\rm O{rcub})))\sp{lcub}\rm 1/D{rcub}&, where D = b-bd and b is from W = qL&\sp{lcub}\rm b{rcub}&. The growth rate may be rewritten in terms of gill area, A, as dW/dt = kA/(A&\sb\infty&/W&\sb\infty\sp{lcub}\rm m{rcub}&)-kW&\sp{lcub}\rm m{rcub}&. Gill areas were …


Movements And Behavior Of Wild And Head-Started Sea Turtles, John A. Keinath Jan 1993

Movements And Behavior Of Wild And Head-Started Sea Turtles, John A. Keinath

Dissertations, Theses, and Masters Projects

Flipper-tagging, aerial surveys, and satellite telemetry was used to investigate the occurrence, migratory routes, distances traveled, swimming speeds, diving behavior, and the relation of water temperature to movements and timing of migration of wild loggerhead (Caretta caretta) and Kemp's ridley (Lepidochelys kempii) sea turtles. The behavior and movements of head-started loggerhead turtles was investigated with satellite telemetry and compared to wild turtles. Flipper-tagged loggerhead and Kemp's ridley turtles inhabit Chesapeake Bay during the warm months and many return in subsequent seasons. Aerial surveys showed that loggerhead turtles migrate from south of Cape Hatteras to northern waters during May and June, …


Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri Jan 1993

Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri

Dissertations, Theses, and Masters Projects

Otoliths, scales, dorsal spines, and pectoral fin rays, of Atlantic croaker, Micropogonias undulatus, were compared for legibility of presumed annuli and precision in repeated readings, to determine the best structure for ageing. Marks on transverse otolith sections were easiest to read and showed the best agreement between readings. Fish collected in Chesapeake Bay and in Virginia and North Carolina coastal waters during 1988-1991 were then aged using otolith sections. Ages 1-8 were recorded, but eight-year-old fish were rare. Marginal increment analysis showed that for ages 1-7 annuli are formed once a year during the period April-May. Otolith age readings were …


Effects Of The Habitat And Size-Specific Predation On The Ontogenetic Shift In Habitat Use By Newly Settled Blue Crabs, Callinectes Sapidus, Adele J. Pile Jan 1993

Effects Of The Habitat And Size-Specific Predation On The Ontogenetic Shift In Habitat Use By Newly Settled Blue Crabs, Callinectes Sapidus, Adele J. Pile

Dissertations, Theses, and Masters Projects

No abstract provided.