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Full-Text Articles in Marine Biology
Time Series Modeling To Ascertain Age In Fisheries Management, Kathleen Sue Kirch
Time Series Modeling To Ascertain Age In Fisheries Management, Kathleen Sue Kirch
OES Theses and Dissertations
The ability to assign accurate ages of fish is important to fisheries management. Accurate ageing allows for the most reliable age-based models to be used to support sustainability and maximize economic benefit. Structures used to age include bones, scales, and most commonly ear bones (otoliths). Assigning age relies on validating putative annual marks by evaluating accretional material laid down in patterns in fish otoliths, typically by marginal increment analysis. These patterns often take the shape of a sawtooth wave with an abrupt drop in accretion yearly to form an annual band and are typically validated qualitatively. Researchers have shown keen …
Atlantic Surfclam (Spisula Solidissima) Population Demographics And Distribution Along The Middle Atlantic Bight, Mauricio González Díaz
Atlantic Surfclam (Spisula Solidissima) Population Demographics And Distribution Along The Middle Atlantic Bight, Mauricio González Díaz
OES Theses and Dissertations
The Atlantic surfclam (Spisula solidissima) is a long-lived benthic biomass dominant organism that occurs on the Middle Atlantic Bight (MAB) continental shelf between 10 m and 50 m. Trends in Atlantic surfclam population specific growth and mortality rates were analyzed using four decades of age and length observations obtained from NOAA stock surveys from the 1980s to 2010s in six regions distributed along the MAB. Atlantic surfclam specific growth rates and asymptotic lengths were estimated from the age and length observations using the von Bertalanffy growth model. The analysis showed that the Atlantic surfclam median asymptotic length in …
Life History And Management Methods For Blueline Tilefish (Caulolatilus Microps) From The United States Mid-Atlantic Region, Michael A. Schmidtke
Life History And Management Methods For Blueline Tilefish (Caulolatilus Microps) From The United States Mid-Atlantic Region, Michael A. Schmidtke
OES Theses and Dissertations
Blueline tilefish (Caulolatilus microps) have recently undergone an increase in landings from waters off the US Mid-Atlantic region (Virginia-Massachusetts). Currently, life history characteristics of blueline tilefish in this area are undescribed. Additionally, appropriate indices of population abundance are not available for this region, necessitating the use of data-limited management methods to set restrictions for harvest of blueline tilefish in this area. This dissertation describes growth and reproductive characteristics of blueline tilefish caught off the coast of Virginia and explores improvements of data-limited management methods that have been applied to blueline tilefish in the US Mid-Atlantic. Blueline tilefish from …
The Effects Of Two Polycyclic Aromatic Hydrocarbons Benzo[A]Pyrene And Naphthalene On Reproductive Success Embryological Development Larval Physiology And Mortality Of The Mud Crab Rhithropanopeus Harisii (Gould), Gregory V. White
OES Theses and Dissertations
Polycyclic aromatic hydrocarbons (PAHs) such as naphthalene (Nap) and benzo[a]pyrene (B[a]P) are common in the water column and sediments of estuarine and coastal areas. The mud crab Rhithropanopeus harrisii was exposed to varying concentrations of Nap or B[a]P to determine the effects on reproductive success, embryological development, larval physiology and mortality. Nap and B[a]P decreased hatching success and prolonged embryological development. Both pollutants produced high abnormality frequencies for egg exposed larvae. Molt frequency and respiratory rates of larvae from non-exposed eggs were more chronically affected by these pollutants than were egg exposed larvae. The EC50 concentrations were determined for …
Polychlorinated Biphenyl Levels In The Ocean Scallop (Placopecten Magellanicus) Gmelin From The Philadelphia Sewage Sludge Disposal Site, Guy Jeffrey Hall
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 …
Environmental Influence On The Migratory Behavior Of The Brown Shrimp In Pamlico Sound North Carolina, Michael Andrew Matylewich
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 …