Marine Biology Commons^™

Polychlorinated Biphenyl Levels In The Ocean Scallop (Placopecten Magellanicus) Gmelin From The Philadelphia Sewage Sludge Disposal Site, Guy Jeffrey Hall

OES Theses and Dissertations

Ocean Scallops (Placopecten magellanicus) were sampled from stations in and around the Philadelphia Disposal Site. Each sample was dissected and aliquots of adductor muscle and reproductive tissue were chemically extracted for Polychlorinated Biphenyls (PCBs). A perchlorinated procedure outlined by Diosady et al., 1972, Aromour, 1973 and Crist et al., 1977 was employed to increase detection levels and simplify quantitation of PCBs. PCB levels were reported in dry weight and lipid weight of both adductor muscle and reproductive tissue. Findings indicated residual levels or PCB/lipid weight increased as lipid levels decreased in both tissue types. Levels detected in all adductor muscle …

Immediate Effects Of A Storm On Coastal Infauna, Fred C. Dobbs, Joseph M. Vozarik

OES Faculty Publications

Effects of storms on benthic infaunal communities have thus far been inferred rather than documented; especially lacking are studies examining immediate effects. To this end, the water column and 2 subtidal benthic sites were sampled before and after Storm David in September 1979. There were large post-storm increases in the numbers of infaunal species and individuals in the water column, presumably due to turbulent benthic boundary conditions. At the benthic stations, there were no pre vs. post-storm differences in the density of infauna; however, the number of species decreased at 1 station. There were storm-associated changes in the rank order …

Monitoring Defecation Activity Of Infaunal Deposit Feeders, Fred C. Dobbs

OES Faculty Publications

An inexpensive, reliable thermistor device capable of monitoring infaunal foraging activity was built and used in the laboratory to examine effects of temperature on sediment reworking by the maldanld polychaete Clymenella torquata. The worm defecated at least once per hour 55.0 % (12.0 "C) to 88.2 % (5.5 "C) of the time. Defecation rate was linearly and positively related to temperature. Estimated volume of sediment ejected per defecation (0.015 ml) did not change with temperature. Results are compared with previous reworking studies of C. torquata.

Phytoplankton Studies Within The Virginia Barrier Islands. Iii. Phytoplankton Composition In A Saline Pond On Smith Island, Harold G. Marshall

Biological Sciences Faculty Publications

The phytoplankton that characterized the Smith Island pond was diverse, with several species of diatoms, dinoflagellates and blue-green algae dominant throughout the year. A total of 146 spp. were noted, predominantly composed of ultra and nanoplankters, that includes representatives from coastal waters. The island ponds are considered eutrophic habitats whose composition is influenced by overwash conditions and in turn introduce populations to surrounding pools and water channels.

The Effects Of Salinity On Growth And Survival Of The Blue Tilapia Oreochromis Aureus (Steindachner) (Pisces Cichlidae), Maylon Lowell White Jr.

OES Theses and Dissertations

The growth rate of the blue tilapia, Oreochromis aureus, was measured in fresh water, 15 ‰ salinity, and 30 ‰ salinity. The fish were given a hormone-treated feed to sex-reverse the females. Acclimations were achieved by raising the salinity only 5 ‰ per day. A biofilter and frequent water changes were used to maintain water quality in each 40 1 system. Synthetic sea salts were used to achieve desired salinity. The fish were grown for 87 days at 27°-30° C.

So significant difference in growth rate occurred among the three treatments. Salinity did not influence mortalities. All fish appeared to …

Environmental Influence On The Migratory Behavior Of The Brown Shrimp In Pamlico Sound North Carolina, Michael Andrew Matylewich

OES Theses and Dissertations

Environmental conditions in the nursery areas during times of development affect the migratory behavior of the brown shrimp (Penaeus aztecus) by influencing growth and natural mortality. A linearized logistic model and a multiple linear model are used to relate environmental factors (week number, water temperature, salinity, air temperature, precipitation, net heating degree days, river discharge) to the cumulative proportion of catch and catch-per-unit-effort, respectively. Multiple regression analysis yielded equations containing the week number, the water temperature and an interaction term as the independent variables. Predictions of total annual yield and total annual catch-per-unit-effort are made using the migratory …

Determining The Uptake And Possible Assimilation Of The Plant Component Of Spartina Detritus By Palaemonetes Pugio Using A Rapid Radiolabeling Method, Michael Peter Crosby

Biological Sciences Theses & Dissertations

Assimilation of the plant components of Spartina alterniflora detritus by the grass shrimp, Palaemonetes pugio, was investigated in a laboratory feeding study. A new radiolabeling procedure was utilized to label the sterilized detritus with ¹⁴C. Organic carbon values were calculated for both S. alterniflora and P. pugio. The grass shrimp were found to assimilate significantly the detritus, with an assimilation efficiency of approximately 14%, and an approximate ingestion rate of 2.508 x l0^-4mg C detritus/mg C shrimp hour^-l occurred. It is hypothesized that coprophagous activity may be important to the completion of digestion of …

Feeding Behavior Of Three Species Of Spionid Polychaetes, Thomas Lane Stokes Jr.

Biological Sciences Theses & Dissertations

Observations of feeding behavior of three species of spionid polychaetes (Paraprionospio pinnata, Polydora ligni, and Streblospio benedicti) were performed in currents ranging from 0 to 10 cm/sec over fine and coarse sediments and in high and low suspended particle loads. These interface feeders may suspension feed, deposit feed, or both simultaneously using a pair of anterior tentaculate feeding palps. P. ligni and S. benedicti were found to alter their palp behaviors in response to experimental manipulations. P. ligni reacted strongly to currents by suspension feeding with coiled palps. S. benedicti reacted strongly and complexly to food particle type and availability. …

A Structural Analysis Of Phytoplankton In The Chesapeake Bay Plume And Adjacent Shelf Waters, Charles K. Rutledge

Biological Sciences Theses & Dissertations

Community structures of phytoplankton populations from the southern portion of the Chesapeake Bight were examined and associated to real and environmental spaces. The sampling design was specifically intended to examine the small scale three dimensional structure of the Chesapeake Bay plume as characterized by its phytoplankton populations. The phytoplankton were sampled at 101 stations, non-synoptically, over a five day period in mid-June, 1980.

Several multivariate numerical techniques were used to determine the relationships between the phytoplankton species distributions and pattern the low salinity plume distribution. A pattern of distribution which approximated the salinity plume resulted from several clustering procedures. Environmental …

A Comparison Of Recruitment Strategies Among Brachyuran Crustacean Megalopae Of The York River, Lower Chesapeake Bay And Adjacent Shelf Waters, David Franklin Johnson

OES Theses and Dissertations

Twenty-one stations forming a transect of the Pamunkey River, York River, lower Chesapeake Bay and adjacent coastal waters were sampled from July through September 1980. The megalopa stages of 11 brachyuran species were sampled. Vertical and horizontal distributions are described for each species in relation to salinity and water column stratification. The megalopae are assigned to three apparent recruitment strategies: retained estuarine, expelled estuarine and retained coastal megalopae. the megalopa stages of estuarine adults, such as Hexapanopeus angustifrons, Neopanope sayi, Panopeus herbstii and Pinnotheres ostreum, are retained in estuarine epibenthic waters, while Rhithropanopeus harrisii are retained in slightly shallower …

A Laboratory Study Of Nongenetic Embryonic Adaptation To Salinity And Its Subsequent Effects Upon Larval Development Of The Grass Shrimp Palaemonetes Pugio Holthius, Paul Jay Anninos

OES Theses and Dissertations

Fertilized embryos of the grass shrimp Palamonetes pugio Holthuis (Decapoda; Caridea) were exposed to two levels of salinity [5 ppt (exposed) and 20 ppt (control)] during incubation to determine the extent to which embryonic adaptation influences subsequent larval development. Larval response to embryonic exposure was measured at three salinities (5 ppt, 10 ppt, and 20 ppt) as the fraction of larvae surviving to metamorphosis and the duration (in days) of larval development. The survival rate of larvae hatched from control, or non-adapted, embryos was significantly influenced by rearing salinity. The differences in survival of pre-adapted larvae (exposed group), however, were …

Myology And Osteology Of Lupinoblennius Herre (Pisces: Blenniidae), William A. Roumillat

Biological Sciences Theses & Dissertations

Certain osteological characters of the genus Lupinoblennius Herre (Pisces: Blenniidae) indicate that it is a specialized member of the tribe Blenniini. Two of these characters are similar to those reported in more advanced tribes. Unifying this genus with the Blenniini are certain muscle patterns that appear unique for the tribe. A comprehensive description of blenny musculature is presented to correct previous literature misinterpretations, and to lay the groundwork for future infrafamilial comparative anatomical studies.

An Evaluation Of Nutrient Sources To Onslow Bay, North Carolina, Larry P. Atkinson, Leonard J. Pietrafesa, Eileen E. Hofmann

CCPO Publications

Hydrographic and current meter data from Onslow Bay, North Carolina, were examined to determine the relative importance of various nutrient sources.

Upwelled Gulf Stream water is the major source of nutrients while rivers represent a minor, if not insignificant, source. In the summer during stratified conditions, the upwelled water penetrates across the shelf, but in the winter the upwelled water is restricted to the outer shelf. Nitrate flux across the 40 m isobath was calculated from continuous temperature and current records. Flux during the summer of 1976 was 2 μM m² sec^-1 which is considerably less than flux …

The Effects Of Copper On Skeletonema Costatum (Greville) Cleve, Susanne Sybille Jackman

Biological Sciences Theses & Dissertations

Copper levels and dominant phytoplankton species composition were examined from six sites in Kings Creek on Virginia's Eastern Shore from March to August 1980. Creek copper levels were determined by an APDCMIBK extraction procedure and ranged from 0.003 to 0.020 mg/1. Diatoms were the dominant phytoplankters with Skeletonema costatum (Greville) Cleve emerging as a major late summer species.

Subsequent laboratory studies involved 96-hour experiments using Skeletonema costatum (clone Skel) grown in enriched natural seawater. The water was collected from Kings Creek and enriched to Guillard and Ryther's (1962) f/2 media levels. Cupric sulfate was added to the experimental culture media …

A Quantitative Description Of Migratory Behavior Of The Brown Shrimp (Penaeus Aztecus) With Applications In Fisheries Management, Anne Madolyn Babcock

OES Theses and Dissertations

A quantitative description of the migratory behavior of the brown shrimp, Penaeus aztecus, was established using the density approach. A theoretical time density was estimated by the proportion of catch and catch per boat hour NOAA-NMFS fisheries statistics collected in Pamlico Sound, the Neuse River, and Core Sound. A clear quantitative description of brown shrimp migratory timing is found in the time densities. The impact of various physical tactors on the progress of the fishery in time and space can be objectively evaluated by using the time density statistics as dependent variables in modeling efforts. The distributions also enable …

The Seasonality Of Occurrence Of Larval And Juvenile Sciaenids In A Virginia Seaside Estuary, James Howard Cowan Jr.

Biological Sciences Theses & Dissertations

The seasonality of occurrence and relative abundance of larval and juvenile fishes, particularly members of the family Sciaenidae, from a Virginia seaside estuary were determined from ichthyoplankton and trawl collections made from March 1979 to March 1980.

The larvae of 20 species distributed among 15 families were identified from the ichthyoplankton. Larvae of the bay anchovy, Anchoa mitchilli, and the Atlantic silverside, Menidia menidia, dominated the samples and made up 57 and 34%, respectively, of all larvae collected. Peak occurrence began in May and continued through August. Fish larvae were present in the study area all year.

Twenty-eight …

Growth And Recruitment Of Two Penaeids In The Bay Of St. Louis, Mississippi During 1979, Teresa C. Heaton

OES Theses and Dissertations

Juvenile brown (Penaeus aztecus, Ives) and white (Penaeus setiferus, Linnaeus) shrimp were collected from two stations of a nursery area in St. Louis Bay Mississippi, during May to October, 1979. Periods of shrimp recruitment and growth were determined to discern whether the concurrent environmental variables of salinity and temperature had an influence on shrimp abundance and yield. Growth estimates were obtained from length frequency measurements of trawl samples taken over a 24-h period per month from each station. An analysis of variance of length versus the variables of sex, month, station, time of day, salinity and …

The Effects Of Salinity On The Growth And Survival Of The Crayfish, Procambarus Actus Actus (Girard), Emily Deaver

OES Theses and Dissertations

The white river crayfish, Procambarus acutus acutus was tested in low salinity water for growth and survival. Thirty animals were placed in each test pool at O, 4 and 8 ppt and grown for 75 days. Growth was defined as increase in carapace length and wet weight. Crayfish grew at a faster rate and had the lowest mortality at 4 ppt. Water hardness, defined as the total concentration of calcium and magnesium expressed as the calcium carbonate equivalent, ranged from 35 mg/1 to 195 mg/1. Pools of crayfish tested at concentrations of approximately 100 mg/1 total hardness exhibited the best …

The Effects Of Elevated Calcium Chloride And Magnesium Chloride Levels On Larval Growth And Survival Of Macrobrachium Rosenbergii (De Man) (Decapoda Palaemonidae) Reared In The Laboratory, James Thomas Michaels Ii

OES Theses and Dissertations

The effects of elevated CaCl₂ , MgCl₂ , combination CaCl₂ and MgCl₂ concentrations and their associated ionic strengths on larval growth and survival of the freshwater prawn, Macrobrachium rosenbergii were investigated in the laboratory. Larvae were reared in diluted seawater of 15 parts per thousand salinity with elevated calcium concentrations of 330 parts per million and elevated magnesium concentrations of 1275 parts per million. Control larvae were also reared with elevated NaCl concentrations to duplicate the ionic strength increases of the combination CaCl₂ - MgCl₂ test solution which had the highest ionic strength. A …

Distribution Of The Dinoflagellate Symbiosis In Astragia Danae As Affected By Light Attenuation, Michael Perry Weston

OES Theses and Dissertations

Spatial zonation of symbiotic and aposymbiotic forms of the temperate coral Astrangia danae provides evidence that light attenuation is an important factor in the distribution of this animal. At four locations in the lower Chesapeake Bay and adjacent offshore waters, symbiotic colonies were observed only in well illuminated surface waters, while aposymbiotic colonies were observed in less illuminated deeper waters. A transition zone exists in which both colony types are found. Colonies on substrates forming a plane parallel to the sea-surface receive a greater radiant flux than colonies on vertical substrates. This extends the depth range of symbiotic colonies located …

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …

Filtration Ingestion And Assimilation Rates Of The Mysid Shrimp Neomysis Americana Smith, Fed Three Food Sources, Robert W. Grabb

OES Theses and Dissertations

Laboratory grazing and assimilation experiments were conducted on the mysid shrimp Neomysis americana in an attempt to assess the suitability of three potential food sources. It was hypothesized that the smaller size classes were primarily herbivores, not becoming omnivorous until attaining lengths of approximately 5-6 mm. Four size classes of mysids from the summer generation, juveniles, immature, adult males, and adult ovigerous females were each fed three concentrations of Artemia salina nauplii, the rotifer Brachionus plicatilis, and the diatom Coscinodiscus lineatus. The mean lengths of the size classes utilized, plus or minus one standard deviation, were 2.5 …

Morphological Variation Among 14 Species Of Callogobius Bleeker (Pisces: Gobiidae), James Francis Mckinney

Biological Sciences Theses & Dissertations

A survey of the variation among the species of the Callogobius complex has been accomplished in order to determine if recognition of more than one genus is warranted for this assemblage of species. Emphasis has been placed on the osteological variation. Relationships among certain species within the Callogobius complex have been exposed. Although there are two well defined species groups within the complex, it is felt that inclusion of all of the examined species within the single genus Callogobius is the most parsimonious course of action.

Structure Of A Subtidal Benthic Community Near Cape Charles, Virginia, R. Michael Ewing

Biological Sciences Theses & Dissertations

Species composition, distribution, and abundance of benthic invertebrates of a subtidal community were examined at a location on the lower Delmarva Peninsula near Cape Charles, Virginia. Macrobenthos was sampled quarterly between June, 1977 and June, 1978 at nine sites along a transect in Old Plantation Creek and the adjacent offshore area. Spatial and temporal patterns of numerically important species are discussed.

Sampling sites and species were grouped by a numerical classification strategy which consisted of the Bray-Curtis similarity measure and group-average clustering. Three faunal assemblages were identified with the aid of constancy and fidelity nodal analyses: (1) a tidal creek …

Feeding Morphologies And Distribution Patterns Of Marine Cladocera In The Lower Chesapeake Bay, Sandra Layne Gilchrist

OES Theses and Dissertations

Temporal and spatial distributions of marine cladocera in the lower Chesapeake Bay estuary were observed over a year-long sampling period. The distributions of cladoceran species throughout the Bay were studied in relation to temperature and salinity. A survey of the species over the entire Bay is included to establish distribution patterns of the various species during a short time period.

Theoretical mathematical principles were used to predict feeding abilities of the Bay species. Mouthparts are described qualitatively and quantitatively to infer function. A mandibular index developed by Itoh (1970) was revised and employed in evaluating feeding methods interspecifically and interspecifically. …

The Spatial And Temporal Distribution Of Fish Eggs And Larvae In Hempstead Bay Estuary, Joseph Adelard Lessard

OES Theses and Dissertations

The ichthyoplankton of Hempstead Bay estuary was sampled from December 1972 to mid March 1974. Eleven stations were sampled by towing a 0.5 meter diameter plankton net. Eggs were most abundant during June and July with an average concentration calculated to be above 5,500/100m³. Egg densities were the lowest during the fall and winter. Larvae were most frequently taken from March through July with densities varying greatly among the samples. The eggs of Brevoortia tyrannus, Anchoa mitchilli, Tautoga onitis, Tautogolabrus adspersus, and Scophthalmus aguosus and the larvae of Menidia menidia, Ammodvtes hexapterus and Pseudopleuronectes americanus constituted most …

Animal-Sediment Relationship Study Of The Western Branch Of The Lynnhaven River, Charles Perry Seymour

Biological Sciences Theses & Dissertations

The animal-sediment relationships of the marine benthic infauna of an estuarine river system, Lynnhaven River, Virginia Beach, Virginia, were studied at six sites, sampled bimonthly for one year. Six species were found to dominate all of the sampling periods and sites for the year. The greatest number of individuals, biomass, and species were found at the sand sites. Deposit feeders were recorded in greater number than suspension feeders at both the sand and the mud sites.

Cluster and nodal analyses were successful in demonstrating animal-sediment relationships for the intertidal regions of the river system.

Mercury, Copper, And Zinc In Selected Ichthyofauna Of Lower Chesapeake Bay And Hampton Roads, Virginia, W. Bruce Aitenhead

OES Theses and Dissertations

Anchovys, croaker, spat, summer flounder and hogchokers were collected monthly to seasonally from November 1972 to October 1973 at three locations in the southern Chesapeake Bay region of Virginia.

The concentrations of mercury, copper and zinc were determined by atomic absorption spectrophotometry in whole fishes. Metal concentration varied with species and location. Anchovys had the highest mean concentrations of mercury and zinc while hog- chokers had the highest mean copper concentration. Mercury levels exceeding O.5 ppm were observed in species from all three loca- tions, but maximum heavy metal concentrations per species were highest in Craney Island fishes.

Temporal variations …

Description Of The Larval Development Of Squilla Empusa Say (Crustacea Stomatopoda) With Aspects Of Larval Ecology In Chesapeake Bay, Steven Gaines Morgan

OES Theses and Dissertations

Larvae of Sguilla empusa were collected from the plankton and were reared in the laboratory to describe the pelagic larval development and the postlarval stage. Nine pelagic stages are passed through before the postlarval stage is attained.

The larvae reared for descriptive purposes were subjected to sixteen combinations of temperature and salinity to determine their tolerance to the two parameters. Larvae survived longer and molted more frequently when reared at 25°/oo and 20°C or 25°C, which corresponds to the natural conditions of the Chesapeake Bay when the larvae were collected.

A three year planktonic survey conducted in the lower region …

Contributions To The Reproductive Biology And Natural History Of The Pirateperch, Aphredoderus Sayanus, Edward O. Murdy

Biological Sciences Theses & Dissertations

The purpose of this study was to describe the micro and macro-anatomy of the reproductive system and the testicular and ovarian development in Aphredoderus sayanus.

Specimens were collected at least once a month from September, 1976, through May, 1977, in Cypress Pond, a part of the Dismal Swamp drainage, outside of Suffolk, Virginia. Forty-three specimens had their gonads examined histologically, of these 13 were males, 29 were females and in one specimen the sex was not determinable.

Aphredoderus sayanus is a spring spawner, spent gonads were found on and after April 13, 1977. Gonads began to ripen in the …