Marine Biology Commons^™

A Histological Investigation Of The Larval Mandibular Organ In The Mud Crab Rhithropanopeus Harrisii (Gould) (Crustacea Decapoda Xanthidae), Lore Lynn Hantske

OES Theses and Dissertations

Mandibular organs of the mud crab, Rhithropanopeus harrisii (Gould) were histologically located and followed throughout the larval cycle to determine their role in metamorphosis. Specimens from each day of the four larval stages and the megalopa stage were embedded in paraffin, sectioned at 8 μm, stained and observed under the microscope for the mandibular organs. The organs were located in the mandibular area of second, third and fourth stage larvae. The organs were probably present in the first stage zoeae and in the megalopa stage, although the

techniques of the study were not sensitive enough to observe them. The …

The Role Of Picoplankton In Phytoplankton Dynamics Of A Temperate Coastal Plain Estuary, Robert Triau Ray

Dissertations, Theses, and Masters Projects

No abstract provided.

Effects Of Food Ration Size On Bioaccumulation Of Kepone By Spot (Leiostomus Xanthurus) And Grass Shrimp (Palaemonetes Pugio) (Pharmacokinetics, Dietary Accumulation, Accelerated Test, Bioconcentration, Assimilation Efficiency), Daniel J. Fisher

Dissertations, Theses, and Masters Projects

Long-term bioaccumulation studies were conducted using ('14)C-Kepone and unlabeled Kepone to determine the significance of dietary accumulation to final Kepone body burdens in spot (Leiostomus xanthurus) and grass shrimp (Palaemonetes pugio). Both food (grass shrimp) and consumer organisms were exposed to aqueous Kepone concentrations of 0.04 (mu)g/l at 23�C for 16-19 days, followed by a 21-28 day clearance phase. Dietary and aqueous sources of Kepone were shown to be additive for both species. Dietary contributions of Kepone represented 9, 18 and 38% of the total Kepone body burden in spot fed contaminated food rations of 4, 8 and 20% mean …

Estuarine Zooplankton Community Structure In Stratified And Well-Mixed Environments (York River, Virginia, Chesapeake Bay), James Edward Price

Dissertations, Theses, and Masters Projects

The community structure and vertical distribution patterns of mesozooplankton in the lower York River, Virginia were examined during August, 1978. Samples were collected in the upper and lower water strata before, during and after destratification of the water column due to tidal mixing. In the stratified pre-mixed water column, distinct zooplankton communities were identified above and below the pycnocline. Pronounced diurnal vertical migrations of Acartia tonsa (all stages) and Pseudodiaptomus coronatus were documented. During the well-mixed hydorgraphic regime, the previously identified communities were not as well defined. There was a greater homogeneity of species assemblages and less pronounced differentiation of …

Trophodynamics Of Estuarine (Salt Marsh) Heterotrophic Nanoplankton (Microbial Ecology, Salt Marsh Ecology, Choanoflagellates, Virginia), Alyce T. Fritz

Dissertations, Theses, and Masters Projects

Seasonal occurrence and activity of heterotrophic nanoflagellates (HNANO or heteroflagellates) and bacteria were studied in a sheltered brackish water embayment of Chesapeake Bay wetlands (Virginia, USA) over a three year period (1981 - 1984). Epifluorescence direct counts and Scanning and Transmission Electron Microscopy (SEM and TEM) techniques were used for the description of organisms, enumeration, and biomass determinations. Seasonal bacterial growth rates and growth and grazing rates of bactivorous HNANO were estimated using diffusion chambers equipped with Nuclepore polycarbonate membrane filters in natural salt marsh tidal pools. Environmental monitoring of nanoplankton populations revealed a seasonal pattern of bacterial abundances with …

The Influence Of Lobster Trap Escape Gaps On Capture And Behavior Of The Spiny Lobster, Panulirus Argus (Latreille), Denis William Frazel

HCNSO Student Theses and Dissertations

Interest in the potential usefulness of lobster trap escape gaps in the Florida spiny lobster fishery prompted an independent examination of their influence on capture and behavior of the spiny lobster, Panulirus argus. A trapping study was conducted off Southeastern Florida during 1984/1985 using control traps, and traps with escape gap openings of 51, 54, and 57 mm. The 51 mm escape gap caught significantly more legal lobsters than any other trap, while the 54 and 57 mm escape gap caught significantly fewer sublegal lobsters. Carapace lengths of lobsters increased as escape gap width increased.

The impact of escape …