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Full-Text Articles in Life Sciences

Description, Distribution, And Abundance Of The Blue Crab, Callinectes Sapidus (Rathbun), Spawning Stock Of The Lower Chesapeake Bay, Patrick John Geer Oct 1993

Description, Distribution, And Abundance Of The Blue Crab, Callinectes Sapidus (Rathbun), Spawning Stock Of The Lower Chesapeake Bay, Patrick John Geer

OES Theses and Dissertations

The lower Chesapeake Bay spawning stock of the blue crab, Callinectes sapidus, (Rathbun), is examined for seven years (1986 - 1992) in an attempt to better understand stock behavior. Three methods of post-stratification are used to describe the distribution and movement of the population over time. The three methods, density strata, geographic zones, and depth strata, did well in explaining movements of the population, indicating a trend of increased concentration of blue crabs near the eastern Bay late in the spawning season - October. The data suggest a bimodal period of spawning and a trimodal period of abundance. The …


Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone, John Roland Moisan Apr 1993

Modeling Nutrient And Plankton Processes In The California Coastal Transition Zone, John Roland Moisan

OES Theses and Dissertations

Two time- and space-dependent, physical-bio-optical models have been developed for the California Coastal Transition Zone (CTZ) region with the overall objective of understanding and quantifying the processes th at contribute to the spatial and temporal development of nutrient and plankton distributions in the CTZ. The first of these models considers only time- and vertical processes at specific locations in the CTZ. The model food web components include: silicate, nitrate, ammonium, two phytoplankton size fractions, copepods, doliolids, euphausiids and a detritus pool. The wavelength dependent attenuation of the subsurface irradiance field, due to sea water, phytoplankton pigment concentrations and dissolved organic …


The Role Played By Semisubmersible Exploratory Drilling Platforms As A Vector In Marine Biological Introductions, Sean S. Bercaw Jan 1993

The Role Played By Semisubmersible Exploratory Drilling Platforms As A Vector In Marine Biological Introductions, Sean S. Bercaw

Theses and Major Papers

Through discussion of Semisubmersible Exploratory Drilling Platforms and their role as vectors in marine biological introductions, this paper establishes a base of knowledge for future referral. Included in this project are details of semisubmersibles, their unique characteristics and operations, historical movements, past introductions, future operations, and continuing potential for invasions. The significance of semisubmersibles as biological vectors is further addressed. Three criteria will be used to assess the significance of the role of semisubmersibles in the introduction of alien species: first, what is the rate of SEDP movements over time; second, how are SEDP movements unique, and what role does …


Conflicts In Use: The Impacts Of The Oil And Gas Industry On The Herring Fishery In The North Sea, Cornelia Ann Pasche Jan 1993

Conflicts In Use: The Impacts Of The Oil And Gas Industry On The Herring Fishery In The North Sea, Cornelia Ann Pasche

Theses and Major Papers

The interaction of the herring (Clupea harengus) with the oil and gas industry in the North Sea is reviewed. The population crash of the herring in the early 1970's and the subsequent closing of that important fishery between 1977 and 1983 has drawn considerable attention to the influences, both biotic and abiotic, affecting the recruitment to the North Sea stock. Current accepted theory points to a change in oceanic current and the subsequent decrease in salinity in the North Sea region, resulting in a change in plankton availability for larval herring as the cause of the recruitment failure during the …


Linking Management And Markets: The Northwest Atlantic Sea Herring Industry And The Case For "Regional" Quotas, Peter Jessup Moore Jan 1993

Linking Management And Markets: The Northwest Atlantic Sea Herring Industry And The Case For "Regional" Quotas, Peter Jessup Moore

Theses and Major Papers

This review and characterization of the U.S. Atlantic sea herring fishery and industry analyzes opportunities for and constraints to developing the herring resource more fully. Chapter 1 describes the herring resource, the existing fishery, and reviews current research into the international transboundary migrations of the Atlantic sea herring. Chapters 2 and 3 describe the development of the herring fishery management plan in the context of the global herring market and the management complications that arise from the transboundary migrations of the stocks. Examples of successful linkages between fisheries management and market development are described in Chapter 4 to illustrate the …


Study Of An Endangered Species Enhancement Program In Coastal Wetlands: Public Perceptions And Management Strategies, Virginia Marueen Witkowski Jan 1993

Study Of An Endangered Species Enhancement Program In Coastal Wetlands: Public Perceptions And Management Strategies, Virginia Marueen Witkowski

Theses and Major Papers

Understanding what motivates public perception and actions is important in assessing public response and forecasting the success of resource management plans. Failure of the policy makers to foresee public reaction can result in expensive delays, bad press and lengthy court battles which at best, increases the cost of implementation and at worst stops resource management projects altogether. An endangered species management program was stopped at the Seal Beach National Wildlife Refuge in Southern California when an animal right's organization protested the euthanizing of non-native red foxes where were decimating endangered populations of California Least terns and Clapper rails in the …


The Dynamics Of An Oligohaline, Macrofaunal, Fouling Community, Michelle Lynne Thompson Neubauer Jan 1993

The Dynamics Of An Oligohaline, Macrofaunal, Fouling Community, Michelle Lynne Thompson Neubauer

Dissertations, Theses, and Masters Projects

No abstract provided.


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 …


Amorphometric And Meristic Study Of The Halfbeak, Hyporhamphus Unifasciatus (Teleostei: Hemiramphidae) From The Western Atlantic, With The Description Of A New Species, Heidi M. Banford Jan 1993

Amorphometric And Meristic Study Of The Halfbeak, Hyporhamphus Unifasciatus (Teleostei: Hemiramphidae) From The Western Atlantic, With The Description Of A New Species, Heidi M. Banford

Dissertations, Theses, and Masters Projects

No abstract provided.


Dynamics Of Fish Assemblages Associated With An Offshore Artificial Reef In The Southern Mid-Atlantic Bight, Aaron J. Adams Jan 1993

Dynamics Of Fish Assemblages Associated With An Offshore Artificial Reef In The Southern Mid-Atlantic Bight, Aaron J. Adams

Dissertations, Theses, and Masters Projects

No abstract provided.


A Survey Of The Stony Coral Community Composition Of Pompano Ledge, Broward County, Florida, With A Preliminary Evaluation Of The Effectiveness Of Mooring Buoys In Reducing Coral Damage, John D. Hocevar Jan 1993

A Survey Of The Stony Coral Community Composition Of Pompano Ledge, Broward County, Florida, With A Preliminary Evaluation Of The Effectiveness Of Mooring Buoys In Reducing Coral Damage, John D. Hocevar

HCNSO Student Theses and Dissertations

Stony corals of Pompano Ledge, First Reef, Broward County, Florida were sampled in situ using a new reef assessment method. The circular-radial method was used to assess the effectiveness of mooring buoys in reducing damage to reefs. Data will be part of a long-term monitoring study of·buoy impacts. The parameter of recent injury was used to provide preliminary information on buoy effectiveness.

Results were as follows: approximately 6% of the study area was covered by stony corals, with an average of 3 colonies per square meter. Diversity based on abundance (H'n) was 1 .7, and diversity based on relative coverage …


Microzooplankton Distributions In The Irish Sea, Carol A. Burkart Jan 1993

Microzooplankton Distributions In The Irish Sea, Carol A. Burkart

HCNSO Student Theses and Dissertations

The purpose of this study was to determine the distributions and abundances of microzooplankton across a front in the Irish Sea, and to test the hypothesis that the structure which develops within the microzooplankton community is the result of the interactions within the communities.

Eight sites were sampled on May 1-2, 1989 along a transect from Liverpool Bay, England to Dundalk Bay, Ireland. The transect crossed both the Liverpool Bay and western Irish Sea fronts; sites were positioned with respect to water type (e.g., coastal, thermally mixed, thermally stratified) . Five sites were sampled by double Longhurst-Hardy Plankton Recorder (LHPR) …


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, …


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.


Comparison Of Uptake And Disposition Of Organic Pollutants In Intermolt And Ecdysial Blue Crabs, Callinectes Sapidus, Judy Lynne Haner Jan 1993

Comparison Of Uptake And Disposition Of Organic Pollutants In Intermolt And Ecdysial Blue Crabs, Callinectes Sapidus, Judy Lynne Haner

Dissertations, Theses, and Masters Projects

No abstract provided.


Responses Of Cytochrome P450ia In Freshwater Fish Exposed To Pulp Mill Effluents In Experimental Stream Channels, Laura Anne Bankey Jan 1993

Responses Of Cytochrome P450ia In Freshwater Fish Exposed To Pulp Mill Effluents In Experimental Stream Channels, Laura Anne Bankey

Dissertations, Theses, and Masters Projects

No abstract provided.


Interspecific And Intraspecific Variability In Placoid Scale Morphology In Relation To Body Form Variability In Squaliformes, Christopher R. Tabit Jan 1993

Interspecific And Intraspecific Variability In Placoid Scale Morphology In Relation To Body Form Variability In Squaliformes, Christopher R. Tabit

Dissertations, Theses, and Masters Projects

An ontogenetic series of nine species; Centrophorus granulosus, Centroscymnus coelolepis, Dalatias licha, Deania calcea, Echinorhinus cookei, Isistius brasiliensis, Oxynotus centrina and Squalus acanthias were studied to determine swimming capabilities, boundary-layer flow conditions and placoid scale functional morphologies. Body morphometric variables included the girth and the distance from snout to the orbitals, origin of the median and paired fins, and the caudal peduncle, body and fin surface area, fin aspect ratios and caudal fin angles. Placoid scales were sampled from sixteen regions across the body. Morphometric variables included the number of scales per area of integument, scale crown width, length and …