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Full-Text Articles in Marine Biology
Morphology And Systematics Of Batrachoidiformes (Percomorphacea: Teleostei), Diego Francisco Biston Vaz
Morphology And Systematics Of Batrachoidiformes (Percomorphacea: Teleostei), Diego Francisco Biston Vaz
Dissertations, Theses, and Masters Projects
Batrachoidiformes, the toadfishes, are benthic fishes that inhabit nearshore subtidal and intertidal habitats, characterized by their dorsoventrally flattened bodies and large pectoral fins. These fishes lack dispersive larvae, and larval development is retained in nests guarded by their parents. To date, 82 species and 23 genera are accepted as valid. Previous studies recognized a single family, Batrachoididae, with four subfamilies: Batrachoidinae, Porichthyinae, Thalassophryninae, and Halophryninae. Interrelationships among subfamilies, however, are unresolved and interrelationships among species are problematic. Despite being a conspicuous member of the coastal fauna, the internal morphology of most species of Batrachoidiformes is unknown, being intraspecific and ontogenetic …
Age, Growth And Reproduction Of Western North Atlantic Butterfly Rays (Myliobatiformes: Gymnuridae), With The Description Of Two New Species, Kristene Teal Parsons
Age, Growth And Reproduction Of Western North Atlantic Butterfly Rays (Myliobatiformes: Gymnuridae), With The Description Of Two New Species, Kristene Teal Parsons
Dissertations, Theses, and Masters Projects
Batoid fishes are among the most threatened and least understood chondrichthyan species worldwide due to their large body size, conservative life-history characteristics, and predominantly coastal distributions where fishing and habitat degradation threaten the stability of populations. A lack of empirical life history data is widespread across batoid taxa — nearly half of all species are considered data deficient, thus hindering species assessments and the development of effective management strategies. Furthermore, many batoid taxa are in need of taxonomic re-examination. Increasing our understanding of life history traits that determine population productivity, such as age and size at maturity, growth rate, and …
Reproductive Altruism, Social Diversity And Host Association In Sponge-Dwelling Snapping Shrimps, Synalpheus, Tin Chi Solomon Chak
Reproductive Altruism, Social Diversity And Host Association In Sponge-Dwelling Snapping Shrimps, Synalpheus, Tin Chi Solomon Chak
Dissertations, Theses, and Masters Projects
The diversity of animal social strategies has interested evolutionary biologists since the time of Darwin. Eusociality—the apex of animal sociality—traditionally characterized by cooperative offspring care, overlapping generations and reproductive division of labor, was until recently known only in insects and a few vertebrate species. The independent evolution of eusociality in shrimps in the genus Synalpheus offers a unique opportunity to test the generality of social evolution theories that are based mainly on insects and social vertebrates. The genus Synalpheus is particularly ideal for comparative analysis because their social organizations are highly diverse, yet they share very similar ecology of being …
Migration Dynamics, Within-Estuary Behaviors And Cardiorespiratory Responses Of Summer Flounder To Selected Estuarine Conditions, Karen M. Capossela
Migration Dynamics, Within-Estuary Behaviors And Cardiorespiratory Responses Of Summer Flounder To Selected Estuarine Conditions, Karen M. Capossela
Dissertations, Theses, and Masters Projects
A comprehensive understanding of migration dynamics, within-estuary behaviors and physiological tolerances of fish is needed to assess and predict future responses of fish to environmental disturbance and to protect habitat necessary for growth and survival. This study adds to current knowledge of summer flounder (Paralichthys dentatus) responses to environmental conditions by (1) examining migration and within-estuarine behaviors of adult summer flounder and (2) establishing summer flounder metabolic requirements and cardiorespiratory responses to variations in hypoxia and temperature. To elucidate use of a southern mid-Atlantic Bight estuary by adult summer flounder, the movements of 45 fish were monitored using acoustic telemetry …
Sources Of Mortality, Movements And Behavior Of Sea Turtles In Virginia, Katherine Lamont. Mansfield
Sources Of Mortality, Movements And Behavior Of Sea Turtles In Virginia, Katherine Lamont. Mansfield
Dissertations, Theses, and Masters Projects
Aerial surveys are commonly used to evaluate in-water sea turtle abundances. A correction is applied to account for turtles diving below the observed surface. Historically, observations of summer/fall surfacing behavior were used for this correction, assuming constant behavior among seasons. Using radio/acoustic telemetry, seasonal differences in sea turtle surfacing behavior were determined among Kemp's ridleys and loggerheads. Mean time spent at surface in the spring ranged between 9.9%-30.0% with significant differences among individuals. Observed surfacing times were higher than historic summer/fall observations (Byles 1988; 5.3%), indicating that historic springtime abundances were overestimated by 50%-80%. Aerial surveys (2001-2004) indicated a 65%-75% …
Ecology And Conservation Of Virginia Shark Species: Analysis Of Thirty Years Of Virginia Long-Line Shark Census Data, 1974--2004, Daniel Stuart Ha
Ecology And Conservation Of Virginia Shark Species: Analysis Of Thirty Years Of Virginia Long-Line Shark Census Data, 1974--2004, Daniel Stuart Ha
Dissertations, Theses, and Masters Projects
Sharks of the Atlantic coast of the United States have suffered increased fishing pressure in last three decades. Commercial and recreational catches jumped in the mid to late 1980's, leading to regulation by the National Marine Fisheries Service in the early 1990's. The Virginia Institute of Marine Sciences' shark long-line survey, begun in 1974, and continuing to the present day, is thus well positioned to look at the effects of this fishing mortality on sharks. Using GAM modelling, six of ten shark species analyzed, including the most common species, Carcharhinus plumbeus, suffered declines of from 98-99% of early abundances in …
Nursery Delineation, Movement Patterns, And Migration Of The Sandbar Shark, Carcharhinus Plumbeus, In The Eastern Shore Of Virginia Coastal Bays And Lagoons, Christina L. Conrath
Nursery Delineation, Movement Patterns, And Migration Of The Sandbar Shark, Carcharhinus Plumbeus, In The Eastern Shore Of Virginia Coastal Bays And Lagoons, Christina L. Conrath
Dissertations, Theses, and Masters Projects
The identification and delineation of nursery areas and areas of aggregation of north Atlantic sharks has been identified as an important information need for future management efforts. The objectives of this project were to use a fishery-independent method to study the overwintering area of juvenile sandbar sharks, to spatially delineate the Eastern Shore nursery area, and to examine movement patterns and space use within this nursery area. Data from 21 satellite transmitters attached to large juvenile sandbar sharks revealed that these sharks primarily occurred off the outer banks of North Carolina, at deeper depths and colder water temperatures during the …
A Descriptive Study Of The Reproductive Biology Of The Veined Rapa Whelk (Rapana Venosa) In The Chesapeake Bay, Erica S. Westcott
A Descriptive Study Of The Reproductive Biology Of The Veined Rapa Whelk (Rapana Venosa) In The Chesapeake Bay, Erica S. Westcott
Dissertations, Theses, and Masters Projects
No abstract provided.
Population Dynamics Of The Smooth Dogfish, Mustelus Canis, In The Northwest Atlantic, Christina L. Conrath
Population Dynamics Of The Smooth Dogfish, Mustelus Canis, In The Northwest Atlantic, Christina L. Conrath
Dissertations, Theses, and Masters Projects
No abstract provided.
Demographics, Production, And Benthic -Pelagic Coupling By The Suspension Feeding Polychaete Chaetopterus Pergamentaceus In The Lower Chesapeake Bay, Michelle Lynne Thompson Neubauer
Demographics, Production, And Benthic -Pelagic Coupling By The Suspension Feeding Polychaete Chaetopterus Pergamentaceus In The Lower Chesapeake Bay, Michelle Lynne Thompson Neubauer
Dissertations, Theses, and Masters Projects
For many shallow water environments, ecosystem function depends on the cycling and flow of materials and energy between benthic and pelagic subsystems. Benthic suspension feeders often are important links between the water column and sediment in coastal ecosystems. Populations of the suspension feeding polychaete Chaetopterus pergamentaceus (previously reported as Chaetopterus variopedatus) are widely distributed along the United States East Coast, ranging from New England to Florida. This species is a structurally and functionally important member of the lower Chesapeake Bay benthic community, where it has maintained stable populations for at least the last 15 years. Little is known regarding the …
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 …
Distribution, Swimming Physiology, And Swimming Mechanics Of Brief Squid Lolliguncula Brevis, Ian K. Bartol
Distribution, Swimming Physiology, And Swimming Mechanics Of Brief Squid Lolliguncula Brevis, Ian K. Bartol
Dissertations, Theses, and Masters Projects
Squids are thought to have physiological and locomotive deficiencies that put them at a competitive disadvantage to fishes and exclude them from inshore, highly variable environments that are rich in nektonic fauna. However, brief squid Lolliguncula brevis may be a notable exception. Trawl surveys revealed that L. brevis, particularly juveniles <6 cm dorsal mantle length (DML), are abundant in the Chesapeake Bay, especially when salinity and water temperature are high, and tolerate a wide range of physical conditions relative to other cephalopods. L. brevis is also different from other cephalopods examined previously because its pattern of oxygen consumption as a function of velocity was found to be parabolic and thus similar to aerial flight, and its swimming costs were competitive with ecologically equivalent fishes. Power-speed curves derived from video footage of swimming squid and hydrodynamic force calculations also were parabolic in shape, with high costs both at low and high speeds because of power requirements for lift generation and overcoming drag, respectively. L. brevis employed various behaviors to increase swimming efficiency and compensate for negative buoyancy, such as swimming in various orientations (e.g., arms-first and tail-first), altering angles of attack of the mantle, arms, and funnel, and using fin activity. Fin motion, which could not be characterized exclusively as drag- or lift-based propulsion, was used over 50--95% of the sustained speed range and provided as much as 78% of the vertical and 55% of the horizontal thrust. Small squid (<3.0 cm DML) used different swimming strategies than larger squid possibly to maximize the benefits of toroidal induction, and aerobic efficiency curves indicated that squid 3--5 cm. DML are most efficient. Brief squid also may take advantage of unsteady phenomena, such as attached vortices, for added lift and thrust. Furthermore, an electromyographic study revealed that L. brevis uses different circular muscle layers for various speeds and like fish has muscular "gears", suggesting that there is specialization and efficient use of locomotive muscle in some cephalopods. Therefore, the presumption that squids are inescapably constrained by a second-rate propulsive system and physiological deficiencies is not applicable to L. brevis.
Aspects Of The Biology Of Sea Turtles In The Mid-Atlantic Bight, William C. Coles
Aspects Of The Biology Of Sea Turtles In The Mid-Atlantic Bight, William C. Coles
Dissertations, Theses, and Masters Projects
I present here an investigation of several aspects of the biology of sea turtles in the mid-Atlantic Bight. During 19 years of data collection, included in this study, strandings have increased for all species of sea turtles in Virginia. Most sea turtle strandings occurred during the spring when juvenile turtles migrate into the Bay (Kemp's ridleys had a second significant stranding peak, during fall migration) along the Southern Bay and Virginia Beach Oceanfront. Sea turtles utilize the Chesapeake Bay as a feeding area when the water temperature approaches 20??C, and they leave after the water temperature drops below 20??C. Although …
Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman
Indo-Pacific Population Structure Of The Black Marlin, Makaira Indica, Inferred From Molecular Markers, Brett Falterman
Dissertations, Theses, and Masters Projects
No abstract provided.
Diet Composition And Feeding Habits Of Large Striped Bass, Morone Saxatilis, In Chesapeake Bay, John F. Walter
Diet Composition And Feeding Habits Of Large Striped Bass, Morone Saxatilis, In Chesapeake Bay, John F. Walter
Dissertations, Theses, and Masters Projects
No abstract provided.
Morphological, Electrophysiological And Behavioral Investigation Of Visual Acuity Of The Juvenile Loggerhead Sea Turtle (Caretta Caretta), Soraya M. Bartol
Morphological, Electrophysiological And Behavioral Investigation Of Visual Acuity Of The Juvenile Loggerhead Sea Turtle (Caretta Caretta), Soraya M. Bartol
Dissertations, Theses, and Masters Projects
A majority of the research on sea turtle vision focuses on the turtle's ability to perceive shapes, colors and brightness cues on land. However, aerial vision is a minor component of the visual ability of sea turtles, potentially used only when surfacing to breathe, while basking, and during female reproductive activities. For my doctoral dissertation, I examined the aquatic visual acuity of juvenile loggerhead sea turtles (Caretta caretta) by investigating the morphology of the eye, the electrophysiology of response to stimuli, and the behavior to specific stimuli. For the morphological experiments, eyes were obtained from loggerheads, euthanized due to injury, …
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 …
Subadult Loggerhead Sea Turtle (Caretta Caretta) Behavior In St. Mary's Entrance Channel, Georgia, United States, David A. Nelson
Subadult Loggerhead Sea Turtle (Caretta Caretta) Behavior In St. Mary's Entrance Channel, Georgia, United States, David A. Nelson
Dissertations, Theses, and Masters Projects
A study of channel utilization and behavior of subadult loggerhead turtles was conducted in the St. Mary's River entrance channel area, Georgia. A total of 38 loggerheads were captured by trawling and instrumented with radio and depth sensitive sonic tags from April to November 1993. Turtles were monitored for 6 to 36 hours continuously for approximately 30 days in the spring (13), summer (13), and fall (14). On a daily basis turtles generally confined their diving activity to one location for one to twelve hours in 10 to 20 m water depths then moved 1 to 5 kilometers to a …
Reproductive Biology Of Spanish Mackerel, Scomberomorus Maculatus, In The Lower Chesapeake Bay, Cynthia L. Cooksey
Reproductive Biology Of Spanish Mackerel, Scomberomorus Maculatus, In The Lower Chesapeake Bay, Cynthia L. Cooksey
Dissertations, Theses, and Masters Projects
Spanish mackerel were purchased from commercial fisheries in the Chesapeake Bay in the period 1993-1994 and processed for biological data to describe reproductive biology. Spanish mackerel are multiple spawners with asynchronous oocyte development and indeterminate fecundity. They spawn in the Chesapeake Bay area from June through August, June being the peak spawning month. Individuals, however, vary greatly in when they begin and end spawning. The presence of Gravid and Running Ripe females indicates spawning inside the Chesapeake Bay, and the capture of small juveniles suggests the region may be used as a nursery grounds. Sex ratios vary greatly, females generally …
Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman
Habitat Complexity As A Determinant Of Juvenile Blue Crab Survival, Jessica L. Schulman
Dissertations, Theses, and Masters Projects
No abstract provided.
A Study Of The Histozoic Oyster Parasite, Perkinsus Marinus: I. Disease Processes In American Oysters (Crassostrea Virginica). Ii. Biochemistry Of Perkinsus Marinus, Aswani K. Volety
Dissertations, Theses, and Masters Projects
Numerous studies have investigated the disease processes of Perkinsus marinus in the oyster, Crassostrea virginica. However, the transmission dynamics and factors affecting P. marinus infection are still unclear. The objectives of this study were to investigate: (1) the principal and most effective lifestage of P. marinus, (2) the synergistic effects of temperature, salinity and P. marinus dose on disease prevalence, (3) suppression of host reactive oxygen intermediates by P. marinus, (4) the localization of acid phosphatase in the parasite, (5) the effects of temperature and salinity on acid phosphatase secretion, and (6) the P. marinus lipid and fatty acid composition. …
Immigration Variability And Post-Settlement Processes Of The Spiny Lobster, Panulirus Argus, In The Exuma Cays, Bahamas, Luis Coba-Cetina
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.
Spawning And Ecology Of Early Life Stages Of Black Drum, Pogonias Cormis, In Lower Chesapeake Bay, Louis Broaddus Daniel Iii
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 …
Age, Growth And Population Dynamics Of The Sandbar Shark, Carcharhinus Plumbeus, At Different Population Levels, Thomas R. Sminkey
Age, Growth And Population Dynamics Of The Sandbar Shark, Carcharhinus Plumbeus, At Different Population Levels, Thomas R. Sminkey
Dissertations, Theses, and Masters Projects
The objectives of my research were to test the hypothesis that compensatory (density-dependent) growth of sandbar shark (Carcharhinus plumbeus) occurred after severe population reduction, to describe the juvenile sandbar shark fauna present in the Chesapeake Bay during 1980-81 and 1990-93, and to perform demographic analyses to examine potential population growth. Age and growth of sandbar sharks were investigated by counting rings in vertebral samples collected in 1980-81 and 1991-92. Age at maturity was 15-16 years for both sample periods and both sexes. For sexes combined, the von Bertalanffy growth parameters were L&\sb{lcub}\infty{rcub}& = 199 cm precaudal length (PCL), K = …
Quantification Of Settlement And Recruitment Processes In Bivalve Mollusks, Patrick Kelly Baker
Quantification Of Settlement And Recruitment Processes In Bivalve Mollusks, Patrick Kelly Baker
Dissertations, Theses, and Masters Projects
Studies were carried out to quantify abundance, mortality, and variability in these parameters, during settlement and recruitment of bivalve mollusks, using the oyster, Crassostrea virginica, as a primary model species. Most work was undertaken in the York River, Chesapeake Bay, Virginia, with additional work in the Indian River, Florida. The period chosen, in the bivalve early life history, was from the late planktonic larva to the early benthic juvenile. Studies were designed to specifically examine (a) abundance of late-stage larvae in the plankton, (b) the relationship between larval abundance and settlement, and (c) mortality immediately following settlement. Variability in abundance …
Life History, Population Dynamics And Yield-Per-Recruit Modeling Of Atlantic Croaker, Micropogonias Undulatus, In The Chesapeake Bay Area, Luiz R. Barbieri
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 …
Larvae And Relationships Of Epinepheline Serranids (Teleostei: Percoidei), Carole Christine Baldwin
Larvae And Relationships Of Epinepheline Serranids (Teleostei: Percoidei), Carole Christine Baldwin
Dissertations, Theses, and Masters Projects
Morphology is described for larvae of Diploprion bifasciatus, Belonoperca chabanaudi, Jeboehlkia gladifer, and Grammistes sexlineatus of the serranid subfamily Epinephelinae. Known larvae of all epinephelines are compared. Larval epinephelines differ in patterns of pigmentation, head spination, sequence of fin formation and morphology of elongate (often spectacularly so!) dorsal-fin spines. Relationships among epinepheline genera are investigated based on phylogenetic analysis of larval and adult morphology. Five monophyletic tribes are cladistically delineated, and relationships among tribes and among genera of the tribe Grammistini are hypothesized. Generic composition of tribes differs from Johnson's (1983) classification only in the allocation of Jeboehlkia to the …
Foraging Ecology Of The Blue Crab, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay, Randa A. Mansour
Foraging Ecology Of The Blue Crab, Callinectes Sapidus Rathbun, In Lower Chesapeake Bay, Randa A. Mansour
Dissertations, Theses, and Masters Projects
This study concurrently quantified blue crab feeding habits and preference, and examined the inter-relationships between diet, predator preference, and predator and prey abundance and distribution in three subestuaries of lower Chesapeake Bay--the James, York and Rappahannock Rivers, Virginia. Complementary laboratory investigations estimated the combined effect of the functional, aggregative and interference responses upon prey and predator survival and predator foraging rates for blue crabs and a common bivalve prey, Macoma balthica, in this system. Crab abundance, prey abundance and diet were correlated such that blue crabs aggregated in areas of highest preferred (i.e., bivalve) prey abundance, as determined through electivity …
Comparative Biology And Population Dynamics Of Searobins (Genus Prionotus) With Emphasis On Populations In The Northwestern Gulf Of Mexico, James G. Hoff Jr
Comparative Biology And Population Dynamics Of Searobins (Genus Prionotus) With Emphasis On Populations In The Northwestern Gulf Of Mexico, James G. Hoff Jr
Dissertations, Theses, and Masters Projects
Eight species of Prionotus, collected from 5-100 m in the Gulf of Mexico along a cross-shelf transect off Freeport, Tx during October 1977-August 1981, were studied to determine life history patterns and how they partition resources. Only four species were abundant: P. tribulus, P. paralatus, P. longispinosus, and P. stearnsi. Prionotus spp. mature at 80 mm (P. stearnsi and P. rubio), 85 mm (P. tribulus and P. paralatus), 100 mm (P. ophryas), 105 mm (P. roseus), and 120 mm (P. longispinosus). Sizes at Age 1 were 99-140 mm (P. tribulus), 99-138 mm (P. longispinosus), 98-122 mm (P. paralatus), 75-125 mm …
Comparative Ecology, Morphology, And Population Genetics Of Black Triggerfish, Melichthys Niger, Kathryn D. Kavanagh
Comparative Ecology, Morphology, And Population Genetics Of Black Triggerfish, Melichthys Niger, Kathryn D. Kavanagh
Dissertations, Theses, and Masters Projects
No abstract provided.