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Articles 1 - 9 of 9

Full-Text Articles in Physical Sciences and Mathematics

Effects Of Oxygen Variation On The Ecology Of Devil's Hole, Death Valley National Park, Norma J. Azad Apr 1998

Effects Of Oxygen Variation On The Ecology Of Devil's Hole, Death Valley National Park, Norma J. Azad

UNLV Theses, Dissertations, Professional Papers, and Capstones

The inability to rear Devil's Hole pupfish, Cyprinodon diabolis Wales, in captivity, when captive propagation has been successful with other species of pupfish, led to the examination of environmental factors which are unique to Devil's Hole. It has been suggested that C. diabolis regularly experience developmental arrest due to hypoxic conditions. This arrest may be reversible in areas of the shallow shelf during periods of photosynthetic activity. Oxygen measurements over the shallow shelf reveal a gradient of oxygen variation with the greatest diel variability over the inner portion of the shelf diminishing to nearly imperceptible diel variation toward the outer …


Modeling Environmental Effects On Msx Prevalence And Intensity In Eastern Oyster (Crassostrea Virginica) Populations, Michelle Christine Paraso Apr 1998

Modeling Environmental Effects On Msx Prevalence And Intensity In Eastern Oyster (Crassostrea Virginica) Populations, Michelle Christine Paraso

OES Theses and Dissertations

An oyster population model coupled with a model for Haplosporidium nelsoni, the causative agent of the oyster disease MSX, was used with salinity time-series constructed from Delaware River flow measurements to study environmentally-induced variations in the annual cycle of this disease. Simulations with this model were designed to investigate the effect of increased or decreased spring freshwater discharge, the timing of high freshwater runoff, the presence or absence of a fall or late spring phytoplankton bloom, and the occurrence of a warm winter on MSX prevalence and intensity in Delaware Bay oyster populations. Model simulations for the lower Bay site …


Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi Jan 1998

Comparative Evolution Of Molecular Markers: An Analysis Of Genetic Variation Within The Blue Marlin (Makaira Nigricans), Vincent Patrick Buonaccorsi

Dissertations, Theses, and Masters Projects

Blue marlin diversity was assessed at mtDNA, scnDNA, microsatellite DNA, and allozyme molecular markers. Hierarchical analysis of molecular variance (AMOVA) revealed that most genetic variation was maintained within populations, with a non-significant fraction attributable to variation among temporal replicates and between locations within oceans. In contrast, inter-ocean divergence was highly significant for a majority of loci within each marker class. Previous studies of mitochondrial DNA (mtDNA; n = 104) genetic variation within the blue marlin revealed two distinct clades of haplotypes, one of which was present only in the Atlantic (the 'Atlantic clade'), at a frequency of 40% &(F\sb{lcub}st{rcub}& = …


Caribbean Spiny Lobster And Their Molluscan Prey: Are Top-Down Forces Key In Structuring Prey Assemblages In A Florida Bay Seagrass System, Martha Nizinski Jan 1998

Caribbean Spiny Lobster And Their Molluscan Prey: Are Top-Down Forces Key In Structuring Prey Assemblages In A Florida Bay Seagrass System, Martha Nizinski

Dissertations, Theses, and Masters Projects

Relative importance of predator-prey dynamics and several environmental variables in structuring gastropod and bivalve diversity and distribution was investigated in the subtropical seagrass and macroalgal community of Florida Bay, a highly productive system and primary nursery and foraging ground for finfish and invertebrate predators, including the numerically dominant Caribbean spiny lobster, Panulirus argus. The molluscan assemblage, a primary food source for P. argus in particular, is speciose (75 gastropod and 25 bivalve species) and a significant component of epifaunal and infaunal invertebrate assemblages within Florida Bay. Two experimental areas, located within separate basins and each comprised of two experimental sites, …


Physical Parameters Affecting Incubating Temperatures In Loggerhead Sea Turtles, Caretta Caretta, In Virginia, William Mason Jones Jan 1998

Physical Parameters Affecting Incubating Temperatures In Loggerhead Sea Turtles, Caretta Caretta, In Virginia, William Mason Jones

Dissertations, Theses, and Masters Projects

Detailed physical profile of eight transplanted loggerhead sea turtle, Caretta caretta, nests were obtained from Virginia and northeastern North Carolina and reburied in Back Bay National Wildlife Refuge (BBNWR), Virginia Beach, Virginia during the summers of 1987, '88, and '89 to determine if the physical location of the egg within the nest had an affect on sex determination. Transplanted nests were reburied in sandy substrate at a depth of 15-60 em on south facing dunes, and a Campbell Scientific data-logger logged synchronously environmental data. The following data were collected: temperatures at various locations within a nest, net absorbed radiation, ambient …


Tagging And Habitat Utilization Of Juvenile Summer Flounder, Paralichthys Dentatus, Richard Thomas Kraus Jan 1998

Tagging And Habitat Utilization Of Juvenile Summer Flounder, Paralichthys Dentatus, Richard Thomas Kraus

Dissertations, Theses, and Masters Projects

No abstract provided.


Oyster Reef Broodstock Enhancement In The Great Wicomico River, Virginia, Melissa Southworth Jan 1998

Oyster Reef Broodstock Enhancement In The Great Wicomico River, Virginia, Melissa Southworth

Dissertations, Theses, and Masters Projects

No abstract provided.


The Birds And Habitat Of Kings Park, Bradley W. Cox Jan 1998

The Birds And Habitat Of Kings Park, Bradley W. Cox

Theses : Honours

Kings Park is a large urban park in the centre of Perth with extensive areas of semi-natural bushland. The park is an important refuge for birds in the metropolitan area but is losing species through habitat disturbance. Understanding the way in which birds are related to their habitat helps to understand the effect of habitat disturbance on the bird community. The aim of this project was to generate guidelines which will aid in the management and conservation of birds in the park, through an understanding of the relationship of the birds to their habitat. The avifauna and various habitat factors …


Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford Jan 1998

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 …