Life Sciences Commons^™

The Reproductive Cycle And Larval Tolerances Of Rangia Cuneata In The James River, Virginia, Thomas David Cain

Dissertations, Theses, and Masters Projects

The autecology of the brackish water clam Rangia cuneata was investigated in the James River, Virginia, from February 1970 to January 1972. The reproductive cycle, combined salinity and temperature effects on embryos and larvae, and setting were studied. Histological slides were made, set collected, and temperature and salinity measurements taken from three populations living in different salinity regimes. Phases of gonad development are described. Gametogenesis started in April and from May through September clams were found in all gonadal phases. Ripe gonads were found from May to late November with no summer or inactive period. It was determined by the …

Variations In Some Serum Constituents Of The Blue Crab, Callinectes Sapidus, Maurice P. Lynch

Dissertations, Theses, and Masters Projects

No abstract provided.

Acute Toxicity Of Unbleached Kraft Mill Effluent (Ukme) To The Oppossum Shrimp, Neomysis Americana Smith, Fred Jacobs

Dissertations, Theses, and Masters Projects

96-hour TL50 values of unbleached kraft mill effluent (UKME) for Neornysis arnericana were found to range from concentrations of 3.29 to 6.85% at 26-28 C and 3.90 to 7.30% at 16-18 C. Differences between batches of effluent proved insignificant in experiments at each temperature regime. Furthermore, UKME did not lose its toxicity, when stored for 5 to 7 days at 4 C. A concentration of 20% effluent killed 100% of the organisms in 8 of the 12 bioassays. Slope functions and confidence limits of TL50 were calculated. This dissertation is from the Joint Program Degree from the College of William …

Postlarval Growth And Reproductive Biology Of The Xanthid Crab, Neopanopetexana Sayi, Richard Carlyle Swartz

Dissertations, Theses, and Masters Projects

No abstract provided.

Benthic Fish Associations On The Continental Slope Of The Middle Atlantic Bight, Douglas F. Markle

Dissertations, Theses, and Masters Projects

No abstract provided.

Larvae And Young Of The Western North Atlantic Bothid Flatfishes, Etropusmicrostomus (Gill) And Citharichthys Arctifroms, Goode In The Chesapeake Bight, Sarah Butler Leonard

Dissertations, Theses, and Masters Projects

No abstract provided.

Iodine Metabolism In Sessile Stages Of Chesapeake Bay Semaeostome Jellyfish, Janet Evelyn Olmon

Dissertations, Theses, and Masters Projects

No abstract provided.

Distribution And Abundance Of Calanoid Copepods In The York River Estuary, Virginia, 1968 And 1969, Victor G. Burrell Jr.

Dissertations, Theses, and Masters Projects

Calanoid copepods were sampled quantitatively at twelve stations in the York River estuary monthly over a two year period. Twenty-two different calanoid species were identified, with five species, Acartia tonsa, A. clausi, Eurytemora affinis, Pseudocalanus minutus and Pseudodiaptomus coronatus making up 95% of the numbers present. Several factors were investigated to determine their biological influence was the ctenophore, Mnemiopsis leidyi, a predator which reduced copepod numbers logarithmically at stations at which it occurred. Increased river flow was followed by large increases in copepod numbers and was the most important physical influence.

Distribution of all calanoid species appearing in the estuary …

Morphology And Ecology Of Chesapeake Bay Decapod Crustacean Larvae, Paul A. Sandifer

Dissertations, Theses, and Masters Projects

This dissertation is from the Joint Program Degree from the College of William & Mary and University of Virginia and awarded by the University of Virginia.

Provisional keys to the marine decapod crustacean zoeae of the Chesapeake Bay are presented. These keys provide distinguishing characters for the specific or generic identification of zoeae of 50 decapod species. Also, provisional classification schemes for the different morphological types of antennae and telsons exhibited by Chesapeake Bay brachyuran larvae are given, and the larval stages of each species or genus considered in the keys are briefly described.

The larval development of eight Chesapeake …

Distribution, Growth, Selective Feeding, And Energy Transformations Of Young-Of-The-Year Blueback Herring, Alosa Aestivalis (Mitchill), In The James River, Virginia, Richard Greig Burbidge

Dissertations, Theses, and Masters Projects

Energy transformations and budget are computers for young-of-the-year blueback herring, Alosa aestivalis, in the James River, Virginia. Distribution, growth, and selective feeding are described. Fish and zooplankton collections were made at five stations in the main channel of the James RIver from June through November 1969. Two 24hr series of samples were collected in July and October 1968 in the Potomac River. A direct relationship existed between standing cropos of zooplankton and distribution, growth, and feeding of blueback herring. Zooplankton densities were highest upstream, where food consumption and growth rates were correspondingly highest. A progressive downstream decrease and upstream increase …

Feasibility Of Artificial Propagation And Introduction Of Hybrids Of The Morone Complex Into Estuarine Environments, With A Meristic And Morphometric Description Of The Hybrids, Jerome Howard Kerby

Dissertations, Theses, and Masters Projects

Laboratory and environmental studies of striped bass (Morone saxatilis) X white perch (M. americana) and striped bass X white bass (M. chrysops) were used to-determine the feasibility of introducing these hybrids into an estuary as a supplement to natural populations of the parental species. Growth patterns, survival, and general hardiness of the hybrids were used as criteria. Growth of striped bass X white perch hybrids in the laboratory was apparently somewhat less than growth of natural populations of striped bass, but was much greater than growth of natural populations of white perch. Hybrid growth was slower than striped bass growth …