Ecology and Evolutionary Biology Commons^™

A Study Of The Zooplankton Composition At A Twenty-Four Hour Station In Waters North Of Cuba, Judith Lee Hensley

Biological Sciences Theses & Dissertations

No abstract.

The Food Habits Of Ictalurus Natalis, Centrarchus Macropterus And Perca Flavescens In Lake Drummond In The Dismal Swamp Of Virginia, Steven C. Russell

Biological Sciences Theses & Dissertations

The food habits of yellow bullhead catfish (Ictalurus natalis), yellow perch (Perea flavescens), and fliers (Centrarchus macropterus) in Lake Drummond in the Dismal Swamp were examined. Seventy yellow bullheads (42 mm to 255 mm), 136 yellow perch (41 mm to 280 mm), and 110 fliers (81 mm to 140 mm), were collected with gill nets, traps, seins, and electro-fishing gear from June through November of 1975. Frequency of occurrence and volumentric data were used to evaluate the relative importance of food items. Spearman's rank correlation coef­ficient was determined from the data to test differences …

An Intensive Study Of The Spring Phytoplankton Bloom In Lynnhaven Bay, Virginia, Donald Lynn Webster

Biological Sciences Theses & Dissertations

Phytoplankton samples were collected biweekly from two stations, one in each branch of Lynnhaven Bay, Virginia over the period January 24 to June 9, 1975. Water temperature, salinity, pH, oxygen, ammonia, urea, reactive nitrite, reactive nitrate, reactive phosphorus, productivity, transparency, and weather conditions were recorded concurrently. Data were manipulated employing analysis of variance, simple correlation, correlation matrices, and forward stepwise multiple regression. Total phytoplankton numbers exhibited a unimodal pattern. A pre-bloom pulse was recorded at both stations in late February. The spring bloom lasted from April through May. Phytoplankton growth was primarily a function of nutrient supply and temperature. Nutrient …

Structural Comparisons Of Four Plant Communities In The Great Dismal Swamp, Claire Virginia Dabel

Biological Sciences Theses & Dissertations

Four plant communities in the Great Dismal Swamp, located on the coastal plain in southeastern Virginia, were sampled and estimates of density, basal area and aboveground standing crop biomass were determined, Biomass was estimated as 229,800 kg/ha in the Chamaecyparis thyoides community and as 344,500 kg/ha in the Taxodium distichum community. Biomass for the two hardwood communities, the

Acer-Nyssa community and mixed hardwood (Quercus-Nyssa-Acer-Liriodendron-Liquidamber) community was estimated as 195,700 kg/ha and 194,600 kg/ha respectively and did not differ significantly (P

Sex Pheromone Activity In The Foveal Glands In The Two Species Of Ixodid Ticks: Dermacentor Andersoni (Stiles) And Dermacentor Variabilis (Say), Lynn Anne Collins

Biological Sciences Theses & Dissertations

Sex pheromone activity in the foveal glands of female Dermacentor andersoni (Stiles) and Dermacentor variabilis (Say) is described. Autoradiography revealed the accumulation of ³⁶Cl in the foveal glands of females during their first 120 hours of feeding on a ³⁶Cl-labeled host. Emissions collected from these females contained a ³⁶Cl-labeled product. This product, however, was absent in emissions collected from the same females with their foveae dorsales obstructed.

Accumulation of ³⁶Cl in the foveal gland, in conjunction with the release of a ³⁶Cl-labeled product through the foveae dorsales, suggest localization of sex pheromone activity within these …

Variation In The Ecology Morphology And Behavior Of The Troglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonchidae) From Different Habitats, Gary Wayne Dickson

Biological Sciences Theses & Dissertations

Populations of the troglobitic amphipod Crangonyx antennatus living in two distinct aquatic habitats were examined for possible variations in their ecology, morphology and behavior. Collections were made seasonally for one year in six Lee Co., Virginia caves, three containing mud-bottom, drip pools and three with small gravel stream habitats. Environmental parameters thought to influence population variation were quantitatively and qualitatively recorded in each of the six caves.

Amphipod densities, body length, female maturity, clutch number and stream washout rates were found to be greater in drip pool habitat populations. Variation was also observed in body coloration and antennal segment-body length …

Improved Techniques For Marking, Night-Viewing, And Aging White-Tailed Deer, Odocoileus Virginianus, Barnard Hodge Powell

Biological Sciences Theses & Dissertations

These studies were concerned with the development of methods to assist investigators of wildlife population research. Specifically they involve the description of (1) A device which enables an investigator to mark deer at medium range using specially modified darts fired by conventional tranquilizer rifles, (2) Construction of infrared viewers and light sources using surplus equipment and (3) Studies to develop a method of making permanent deer dental impressions under field conditions.

The Distribution Of Submersed Hydrophytes In Currituck Sound, Steven Harry Davis

Biological Sciences Theses & Dissertations

The rooted submergent flora of Currituck Sound, North Carolina was determined, and the distributions of its species investigated with respect to salinity, substrate texture, depth, pH, turbidity and species co-occurrence. Eight species of hydrophytes were found: Potamogeton pectinatus, Fotamogeton perfoliatus, Ruppia maritima, Zannichellia palustris, Najas guadalupensis, Elodea nuttallii, Vallisneria americana, and Myriophyllum spicatum. The mean salinities at which each species occurred ranged from 1.0 ppt for E. nuttallii to 3.1 ppt for Z. palustris, Ruppia maritima, Z palustris and V. americana were the only species that commonly occurred on coarse-grained substrates. Elodea nuttallii and N. guadalupensis …

Seasonal Distribution Of Higher Marine And Aquatic Fungi In The Back Bay National Wildlife Refuge, Scott Schatz

Biological Sciences Theses & Dissertations

Abstract unavailable.

Genetic Studies Of Cave And Spring Populations Of The Freshwater Amphipod Crustacean Gammarus Minus Say, Steven Wolf Hetrick

Biological Sciences Theses & Dissertations

The amphipod Gammaru. minus has three morphotypes in its Appalachian range : (1) a spring form with well-developed eyes, (2) an intermediate cave form with slightly reduced eyes, and (3) an extreme cave form with greatly reduced eyes. This study compares the genetic structure of populations in two karst areas and analyzes the genetics of populations of the three morphotypes.

Genetic data were collected from populations in the Ward's Cove, Virginia and Greenbrier Valley, West Virginia karst areas using zone electrophoresis zymograms. One hundred percent of the Ward's Cove populations are polymorphic at both MDH-1 and PEP 1 loci …

Osteology Of Trypauchenichthys Sumatrensis Hardenburg, Christine Parrish Baer

Biological Sciences Theses & Dissertations

The osteology of a Malaysian goby was examined in detail and compared to other gobioids. Results indicated that Trypauaheniahthys sumatrensis is a specialized, but definite member of the Gobioidei. Some osteological characteristics of a related fish, Trypauchen vagina, were also discussed.

Studies On The Causes Of Tree Distribution In A Forest Type In The Dismal Swamp National Wildlife Refuge, Thomas A. Janszen

Biological Sciences Theses & Dissertations

Vegetational composition and environmental parameters were analyzed in a forest type of the Dismal Swamp. A 0.5 ha forest stand was divided into 200 5 x 5 meter contiguous quadrats and the tree size classes were precisely mapped. Fifty soil samples were analyzed for texture, pH, and major nutrients. A topographic map was constructed with precision to 0.01 ft. Analysis of variance tests showed non-randomness to exist in soil texture and nutrient content while homogeneity tests showed non-randomness in distribution of some woody species. Factor analysis indicated no significant correlations between soil quality, topography, and woody species. Findings indicate that …

Observations On The Distribution And Composition Of Zooplankton In Portions Of The Intracoastal Waterway, Virginia, O. Clair Hillard Jr.

Biological Sciences Theses & Dissertations

Five stations were established in the Southern Branch of the Elizabeth River, the Dismal Swamp Canal, the Albemarle and Chesapeake Canal and the North Landing River. Representative samples of zooplankton were taken from October 1971 to June 1972. A. total of 57 species were identified and discussions regarding seasonal distribution in relation to physical factors and circulation are presented.

The composition of the zooplankton was found to fluctuate greatly due to the variables characteristic of the study area. The combined effect of tidal flow with freshwater input in conjunction with drainage from the Great Dismal Swamp, results in isolated populations …

The Ecology Of The Dominant Tick Species In The Northwestern Portion Of The Dismal Swamp National Wildlife Refuge, Mary Keith Garrett

Biological Sciences Theses & Dissertations

Elements of the ecology of the two dominant man-biting ticks were studied during 1971-1973 in two locations in Southeastern Virginia, namely, what is now the Dismal Swamp National Wildlife Refuge and Newport News City Park. Tick species composition, relative abundance, density, and distribution in the two areas were compared. In addition, the Dismal Swamp locality was used as a test area for studies on the survival of native, lab reared and translocated Dermacentor variabilis (Say) and Amblvomma americanum (L.) in relation to selected abiotic factors. The Newport News locality served as a control area for these studies.

The species …

The Use Of Color Infrared Aerial Photography In Determining Salt Marsh Vegetation And Delimiting Man-Made Structures Of Lynnhaven Bay, Virginia, Robert E. Holman Lll

Biological Sciences Theses & Dissertations

Color infrared aerial photography was found to be superior to color aerial photography in an ecological study of Lynnhaven Bay, Virginia. The research was divided into three phases: 1) determination of the feasibility of correlating color infrared aerial photography with wetland species composition and zonation patterns, 2) determination of the accuracy of the aerial interpretation and problems related to the aerial method used, and 3) comparison of developed with undeveloped areas along Lynnhaven Bay's shoreline.

Wetland species composition and zonation patterns of major cones were correlated with aerial infrared photography and resulted in a high degree of accuracy. Problems with …

An Ecological Study Of The Craney Island Disposal Area In Hampton Roads, Virginia, David Wallace Laist

Biological Sciences Theses & Dissertations

A one year ecological study was conducted on the Craney Island Disposal Area in Hampton Roads, Virginia. This study attempted to identify the flora and fauna inhabiting the spoil deposits and trace the development of communities from the time of deposition through the initial stages of succession.

One hundred and ninety-two species were identified including 48 vascular plants, 66 insects, 48 birds, 18 species of algae, 4 crustaceans, and 8 vertebrates. The study area was divided into six zones based on substrate characteristics and species composition. The successional patterns and biotic interactions within each zone were discussed.

Seasonal Composition Of Zooplankton In The Lafayette River, Norfolk, Virginia, Dahn E. Crandall

Biological Sciences Theses & Dissertations

Abstract unavailable.

Community Structure And Production In A Marsh On The Southern Branch Of The Elizabeth River, Virginia, Michael Bassett Robblee

Biological Sciences Theses & Dissertations

Four different plant communities occur on the Southern Branch of the Elizabeth River, Virginia, 1. Spartina alterniflora, 2. Distichlis spicata - Spartina patens - Juncus roemerianus, J. Baccharis halimifolia - Iva frutescens and 4. Spartina cynosuroides. The cordgrasses s. alterniflora and S. cynosuroides dominate the marsh.

Based-on standing crop estimates S. alterniflora produced 1218.6 grams dry wt/m² and S.cynosuroides 1681.3 grams dry wt/m², which is much higher than generally assumed for Virginia marshes. Evidence for the presence of two crops of S. alterniflora on the marsh during the growing season is-presented.

Two animal associations, composed …

A Zooplankton Study Of Stumpy Lake, Virginia Beach, Virginia, Jose E. Hernandez

Biological Sciences Theses & Dissertations

A one year study was made of the zooplankton composition in Stumpy lake, a reservoir in the city of Virginia Beach, Virginia. Quantitative and qualitative -parameters were investigated under field conditions. The analysis of the data presents information on the monthly dynamics or the zooplankton and other fluctuations in the lake environment. It is the intention or this study to emphasize the seasonal changes in the zooplankton community and their relationship to the ecological factors responsible for these variations.

A Comparative Limnological Survey Of Brackish-Water Lake And A Fresh-Water Lake At Mount Trashmore, Virginia Beach, Virginia, Gene Ramon Cocke

Biological Sciences Theses & Dissertations

No abstract.

A Simulation Model Of Peromyscus Leucopus In An Area Of The Great Dismal Swamp, James E. Paschal Jr.

Biological Sciences Theses & Dissertations

A computer simulation model was developed to explain the population dynamics of the white-footed mouse (Peromyscus leucopus) in an area of the Great Dismal Swamp. The model was designed to provide an experimental base for future studies. The model indicates relationships between food availability, home range size, competition with Peromyscus nuttali habitat selection and reproduction.

White-footed mice were trapped in the Old Dismal Town site during each season from April, 1972 through March, 1973. The age-sex structure of the population was determined, and was compared with the simulated structure. Although there were significant discrepancies between the comparisons, the …

Seasonal Composition Of Zooplankton Of Lower Chesapeake Bay And Virginia Coastal Waters, Elizabeth W. Atkinson

Biological Sciences Theses & Dissertations

Abstract unavailable.

Phytoplankton Distribution In Waters Off The Northeastern Coast Of The United States, Sharon H. Craft

Biological Sciences Theses & Dissertations

Abstract unavailable.

Diurnal Studies At A Station On An Urban Estuary In Norfolk, Virginia, Burton Marc Golue

Biological Sciences Theses & Dissertations

No abstract.

Plant Succession In The Great Dismal Swamp Of Virginia, Susan Woodward Walker

Biological Sciences Theses & Dissertations

Vegetational composition and environmental parameters were analyzed. for 14 stands. Cluster diagrams based on index of similarity values illustrated interstand relationships. The Index of Fluctuation was developed for the analysis of intrastand dynamics. Based on the densities and numbers of species of trees and saplings within a stand, it indicated degree of compositional stability. It was concluded that present vegetation is divided into relatively distinct communities which have resulted, at least in part, from disturbance.

Phytoplankton Composition At Lake Drummond In The Dismal Swamp, Virginia, William Howard Poore Jr.

Biological Sciences Theses & Dissertations

Abstract unavailable.

Trap Manifested Behavior Trap Reflected Density Trap Reflected Distribution And Foods Consumed By Raccoons (Procyon Lotor L.) In Two Natural Areas Of Virginia, Elton L. Winslow

Biological Sciences Theses & Dissertations

A study was undertaken comparing populations of raccoons (Procyon lotor L.) in two natural areas of Virginia, one in the Piedmont physiographic province at Montpelier and the other in the coastal plain at Newport News. Comparisons were made with respect to differences in: (1) capture and recapture success, (2) relative trap reflected density, (3) trap reflected distribution with respect to aquatic habitat, and (4) in food consumption. Comparison of capture data indicated that capture success per 100 trap nights was much higher at Newport News (1.58) than at Montpelier (.76). However a similar comparison of recapture success per …