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Biological Sciences Faculty Publications

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Articles 151 - 180 of 189

Full-Text Articles in Marine Biology

New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe Jan 2005

New Species Of Amphipod Crustaceans In The Genera Tegano And Melita (Hadzioidea : Melitidae) From Subterranean Groundwaters In Guam, Palau, And The Philippines, Thomas R. Sawicki, John R. Holsinger, Thomas M. Iliffe

Biological Sciences Faculty Publications

Three new species of Tegano are described, two from caves on Panglao Island, Bohol, Philippines, and one from a cave on Peleliu Island, Palau. Sriha vagabunda from Sri Lanka is reassigned to the genus Tegano based primarily on the high degree of similarity between Sriha vagabunda and species of Tegano and the fact that these species exhibit a great deal of variation in the reduction of the mandibular palp. A new species of Melita with characters intermediate between those defining the genera Abludomelita, Melita, and Paraniphargus is described from a spring on Guam. The characters of the new …

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Phytoplankton Composition Within The Tidal Freshwater-Oligohaline Regions Of The Rappahannock And Pamunkey Rivers In Virginia, Harold G. Marshall, Lubomira Burchardt Jan 2004

Phytoplankton Composition Within The Tidal Freshwater-Oligohaline Regions Of The Rappahannock And Pamunkey Rivers In Virginia, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

The Rappahannock River is a major river system across north central Virginia prior to entering the Chesapeake Bay. In contrast, the Pamunkey River is smaller in size and joins the Mattoponi River to form the York River, which flows parallel to the Rappahannock before it also flows into Chesapeake Bay. A unique mixing area for both flora and environmental conditions exists in the tidal freshwater-oligohaline region of both rivers. This is a dynamic mixing section where freshwater and estuarine species are subject to the interaction of river flow and daily tidal rhythms. The phytoplankton composition in this region of the …

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A New Pathogenic Virus In The Caribbean Spiny Lobster Panulirus Argus From The Florida Keys, Jeffrey D. Shields, Donald C. Behringer Jr. Jan 2004

A New Pathogenic Virus In The Caribbean Spiny Lobster Panulirus Argus From The Florida Keys, Jeffrey D. Shields, Donald C. Behringer Jr.

Biological Sciences Faculty Publications

A pathogenic virus was diagnosed from juvenile Caribbean spiny lobsters Panulirus argus from the Florida Keys. Moribund lobsters had characteristically milky hemolymph that did not clot. Altered hyalinocytes and semigranulocytes, but not granulocytes, were observed with light microscopy. Infected hemocytes had emarginated, condensed chromatin, hypertrophied nuclei and faint eosinophilic Cowdry-type-A inclusions. In some cases, infected cells were observed in soft connective tissues. With electron microscopy, unenveloped, nonoccluded, icosahedral virions (182 +/- 9 nm SD) were diffusely spread around the inner periphery of the nuclear envelope. Virions also occurred in loose aggregates in the cytoplasm or were free in the hemolymph. …

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Hydrodynamic Stability Of Swimming In Ostraciid Fishes: Role Of The Carapace In The Smooth Trunkfish Lactophrys Triqueter (Teleostei : Ostraciidae), Ian K. Bartol, Morteza Gharib, Daniel Weihs, Paul W. Webb, Jay R. Hove, Malcolm S. Gordon Jan 2003

Hydrodynamic Stability Of Swimming In Ostraciid Fishes: Role Of The Carapace In The Smooth Trunkfish Lactophrys Triqueter (Teleostei : Ostraciidae), Ian K. Bartol, Morteza Gharib, Daniel Weihs, Paul W. Webb, Jay R. Hove, Malcolm S. Gordon

Biological Sciences Faculty Publications

The hydrodynamic bases for the stability of locomotory motions in fishes are poorly understood, even for those fishes, such as the rigid-bodied smooth trunkfish Lactophrys triqueter, that exhibit unusually small amplitude recoil movements during rectilinear swimming. We have studied the role played by the bony carapace of the smooth trunkfish in generating trimming forces that self-correct for instabilities. The flow patterns, forces and moments on and around anatomically exact, smooth trunkfish models positioned at both pitching and yawing angles of attack were investigated using three methods: digital particle image velocimetry (DPIV), pressure distribution measurements, and force balance measurements. Models …

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Distribution Of The Euryhaline Squid Lolliguncula Brevis In Chesapeake Bay: Effects Of Selected Abiotic Factors, I. K. Bartol, R. Mann, M. Vecchione Jan 2002

Distribution Of The Euryhaline Squid Lolliguncula Brevis In Chesapeake Bay: Effects Of Selected Abiotic Factors, I. K. Bartol, R. Mann, M. Vecchione

Biological Sciences Faculty Publications

The majority of cephalopods are thought to have limitations arising from physiology and locomotion that exclude them from shallow, highly variable, euryhaline environments. The brief squid Lolliguncula brevis may be a notable exception because it tolerates low salinities, withstands a wide range of environmental conditions, and swims readily in shallow water. Little is known about the distribution of L. brevis in Chesapeake Bay, a diverse and highly variable estuary. Therefore, a survey of L. brevis was conducted in the Virginia portion of Chesapeake Bay from 1993 to 1997 using a 9.1 m otter trawl, and the effects of selected factors …

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Evidence For Infanticide In Bottlenose Dolphins Of The Western North Atlantic, Dale G. Dunn, Susan G. Barco, D. Ann Pabst, William A. Mclellan Jan 2002

Evidence For Infanticide In Bottlenose Dolphins Of The Western North Atlantic, Dale G. Dunn, Susan G. Barco, D. Ann Pabst, William A. Mclellan

Biological Sciences Faculty Publications

Nine bottlenose dolphin (Tursiops truncatus) calves that stranded in Virginia in 1996 and 1997 died of severe blunt-force trauma. Injuries were concentrated on the head and chest and multiple rib fractures, lung lacerations, and soft tissue contusions were prominent. Skeletal and/or soft tissue trauma occurred bilaterally in all of the calves. One had a bite wound across the left mandible that exhibited deep punctures consistent with the tooth placement in an adult bottlenose dolphin. The lesions were not compatible with predation, boat strike, fisheries interactions, rough-surf injury, or blast injury. However, they were similar to traumatic injuries described in stranded …

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Autotrophic Picoplankton: Their Presence And Significance In Marine And Freshwater Ecosystems, Harold G. Marshall Jan 2002

Autotrophic Picoplankton: Their Presence And Significance In Marine And Freshwater Ecosystems, Harold G. Marshall

Biological Sciences Faculty Publications

No abstract provided.

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Swimming Mechanics And Behavior Of The Shallow-Water Brief Squid Lolliguncula Brevis, Ian K. Bartol, Mark R. Patterson, Roger Mann Nov 2001

Swimming Mechanics And Behavior Of The Shallow-Water Brief Squid Lolliguncula Brevis, Ian K. Bartol, Mark R. Patterson, Roger Mann

Biological Sciences Faculty Publications

Although squid are among the most versatile swimmers and rely on a unique locomotor system, little is known about the swimming mechanics and behavior of most squid, especially those that swim at low speeds in inshore waters. Shallow-water brief squid Lolliguncula brevis, ranging in size from 1.8 to 8.9 cm. in dorsal mantle length (DML), were placed in flumes and videotaped, and the data were analyzed using motion-analysis equipment. Flow visualization and force measurement experiments were also performed in water tunnels. Mean critical swimming speeds (Ucrit) ranged from 15.3 to 22.8 cm s-1, and mean …

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Life-History Evolution In Guppies. Vii. The Comparative Ecology Of High- And Low-Predation Environments, David Reznick, Mark J. Butler Iv, Helen Rodd Feb 2001

Life-History Evolution In Guppies. Vii. The Comparative Ecology Of High- And Low-Predation Environments, David Reznick, Mark J. Butler Iv, Helen Rodd

Biological Sciences Faculty Publications

Prior research has demonstrated a strong association between the species of predators that co-occur with guppies and the evolution of guppy life histories. The evolution of these differences in life histories has been attributed to the higher mortality rates experienced by guppies in high-predation environments. Here, we evaluate whether there might be indirect effects of predation on the evolution of life-history patterns and whether there are environmental differences that are correlated with predation. To do so, we quantified features of the physical and chemical environment and the population biology of guppies from seven high-and low-predation localities. We found that high-predation …

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Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall Jan 2001

Trachelomonas Spp. And Other Euglenophyceae Taxa In A Southeastern Virginia Lake, Harold G. Marshall

Biological Sciences Faculty Publications

Trachelomonas species from Lake Kilby, a reservoir lake in southeastern Virginia are described with supportive electron micrographs. The most abundant Trachelomonas species were T. hispida and T. volvocina. Other members of the Euglenophyceae occurring in this lake are identified.

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Aerobic Respiratory Costs Of Swimming In The Negatively Buoyant Brief Squid Lolliguncula Brevis, Ian K. Bartol, Roger Mann, Mark R. Patterson Jan 2001

Aerobic Respiratory Costs Of Swimming In The Negatively Buoyant Brief Squid Lolliguncula Brevis, Ian K. Bartol, Roger Mann, Mark R. Patterson

Biological Sciences Faculty Publications

Because of the inherent inefficiency of jet propulsion, squid are considered to be at a competitive disadvantage compared with fishes, which generally depend on forms of undulatory/oscillatory locomotion. Some squid, such as the brief squid Lolliguncula brevis, swim at low speeds in shallow-water complex environments, relying heavily on fin activity. Consequently, their swimming costs may be lower than those of the faster, more pelagic squid studied previously and competitive with those of ecologically relevant fishes. To examine aerobic respiratory swimming Costs, O2 consumption rates were measured for L. brevis of various sizes (2-9 cm. dorsal mantle length, DML) …

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The 6th International Conference And Workshop On Lobster Biology And Management: An Introduction, Mark J. Butler Iv Jan 2001

The 6th International Conference And Workshop On Lobster Biology And Management: An Introduction, Mark J. Butler Iv

Biological Sciences Faculty Publications

Every three years or so, the International Conference and Workshop on Lobster Biology and Management (ICWL) brings together lobster scientists, fishery managers, and industry representatives from around the world for a week of scientific presentations, workshops, and discussions on lobster biology and management. The first ICWL was held in Perth, Australia, in January 1977. Its purpose was to bring together a small group of lobster researchers from the USA and Australia to discuss common issues and themes. That initial workshop spawned a continuing series of meetings that have become the international lobster conference for scientists—the equivalent of an international congress …

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Estuarine Relationships Between Zooplankton Community Structure And Trophic Gradients, Gyung Soo Park, Harold G. Marshall Jan 2000

Estuarine Relationships Between Zooplankton Community Structure And Trophic Gradients, Gyung Soo Park, Harold G. Marshall

Biological Sciences Faculty Publications

Zooplankton and water quality parameters were investigated at eight mesohaline stations in the lower Chesapeake Bay and Elizabeth River from January through December 1994 to identify the changes of zooplankton community structure with increased eutrophication. The total micro- and mesozooplankton biomass decreased with the increase of eutrophication. However, the relative proportion of microzooplankton increased with increased eutrophication. Within highly eutrophied waters, the small oligotrichs (m) and rotifers dominated the total zooplankton biomass (as carbon). However, tintinnids, copepod nauplii and mesozooplankton significantly decreased with the increase of eutrophication. These patterns were consistent throughout the seasons and had significant relationships statistically. These …

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Adaptive Strategies That Reduce Predation On Caribbean Spiny Lobster Postlarvae During Onshore Transport, Charles A. Acosta, Mark J. Butler Iv May 1999

Adaptive Strategies That Reduce Predation On Caribbean Spiny Lobster Postlarvae During Onshore Transport, Charles A. Acosta, Mark J. Butler Iv

Biological Sciences Faculty Publications

Like many marine species with meroplanktonic larvae, the Caribbean spiny lobster (Panulirus argus) has a postlarval stage that moves from the oceanic plankton to inshore nurseries only under specific environmental conditions (i.e., at night, in the surface water layer, on the flood tide, and during new moon), presumably to avoid predation or to enhance onshore transport. Using held and mesocosm experiments, we compared predation on planktonic postlarvae swimming at night near the surface and bottom over coastal habitats along typical offshore-inshore transport paths and determined whether predation rates differed between lunar periods (new moon vs, full moon) and with prey …

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The Cause And Consequence Of Ontogenetic Changes In Social Aggregation In New Zealand Spiny Lobsters, Mark J. Butler Iv, Alistair B. Macdiarmid, John D. Booth Jan 1999

The Cause And Consequence Of Ontogenetic Changes In Social Aggregation In New Zealand Spiny Lobsters, Mark J. Butler Iv, Alistair B. Macdiarmid, John D. Booth

Biological Sciences Faculty Publications

Ontogenetic changes in the behavior, spatial distribution, or habitat use of a species are presumably adaptations to ecological forces that differ in their effect on various life stages. The New Zealand rock lobster Jasus edwardsii is one of several species of spiny lobster that exhibits dramatic ontogenetic shifts in sociality and spatial distribution, and we tested whether such changes are adaptive. We first surveyed several natural populations of J. edwardsii to document size-specific differences in aggregation. To determine if chemical cues discharged by conspecifics promote aggregation of certain ontogenetic stages, we tested the responsiveness of lobsters of 3 ontogenetic stages …

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Growth And Feeding Studies On The Algal Feeding Stage Of A Pfiesteria-Like Dinoflagellate, David W. Seaborn, A. Michelle Seaborn, William M. Dunstan, Harold G. Marshall Jan 1999

Growth And Feeding Studies On The Algal Feeding Stage Of A Pfiesteria-Like Dinoflagellate, David W. Seaborn, A. Michelle Seaborn, William M. Dunstan, Harold G. Marshall

Biological Sciences Faculty Publications

The dinoflagellate Cryptoperidiniopsis sp. was isolated from sediment samples taken from Virginia estuaries, and established in culture for subsequent growth and feeding studies. The maximum abundance, or yield, of Cryptoperidiniopsis is exponentially related to the concentration of algal prey and is saturated at about 4.00 X 105 mL-1. Salinity from 10-20 ppt and temperature between 15-25 C have no effect on the yield of this form of Cryptoperidiniopsis. Light intensity has a secondary effect in that the algal prey reproduces more quickly in higher light as they are being grazed. Growth rates of Cryptoperidiniopsis were …

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Water Quality Relationships To Concentrations Of Pfiesteria-Like Organisms In Virginia Estuaries For 1998., Everett P. Weber, Harold G. Marshall Jan 1999

Water Quality Relationships To Concentrations Of Pfiesteria-Like Organisms In Virginia Estuaries For 1998., Everett P. Weber, Harold G. Marshall

Biological Sciences Faculty Publications

A series of statistical analyses were performed to identify the relationship between abundance of dinoflagellates grouped as Pfiesteria-like organisms and a set of 25 water quality variables from May through October of 1998 at 41 estuarine locations. Although regions were identified in relation to seasonal density of cells present, there were no strong relationships to specific water quality variables. Factors that may have influenced these results included: a) several species were included in the group analyzed and this composite did not respond as a unit to changing environmental conditions; b) cell concentrations were low and there were a large …

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Mesozooplankton Distribution And Abundance In The Pagan River: A Nutrient Enriched Subestuary Of The James River, Virginia, Lillian N. Davis, Harold G. Marshall Jan 1998

Mesozooplankton Distribution And Abundance In The Pagan River: A Nutrient Enriched Subestuary Of The James River, Virginia, Lillian N. Davis, Harold G. Marshall

Biological Sciences Faculty Publications

The mesozooplankton in the Pagan River was dominated by calanoid copepods, with abundance peaks occurring during late winter-early spring and from late summer into early fall. This included spring, summer, and fall abundance maxima. The total mean abundance of the mesozooplankton was 3,008/m3.

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Phytoplankton Composition Within The Tidal Freshwater Region Of The James River, Virginia, Harold G. Marshall, Lubomira Burchardt Jan 1998

Phytoplankton Composition Within The Tidal Freshwater Region Of The James River, Virginia, Harold G. Marshall, Lubomira Burchardt

Biological Sciences Faculty Publications

Based on a 10.5 year data set, 271 taxa were identified at a single tidal freshwater station in the James River. The mean monthly concentrations of major algal categories, total biomass and productivity are given. Diatom maxima were associated with peak periods of river discharge, with chlorophytes, cyanobacteria, and autotrophic picoplankton abundance and productivity greater during reduced river flow and more stable water conditions.

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Cladistic Analysis Of 37 Mediterranean Bogidiellidae (Amphipoda), Including Bogidiella Arista, New Species, From Turkey, Stefan Koenemann, Ronald Vonk, Frederick R. Schram Jan 1998

Cladistic Analysis Of 37 Mediterranean Bogidiellidae (Amphipoda), Including Bogidiella Arista, New Species, From Turkey, Stefan Koenemann, Ronald Vonk, Frederick R. Schram

Biological Sciences Faculty Publications

A new subterranean amphipod species, Bogidiella (Medigidiella) arista, found in the mesopsam mic ground waters of southern Anatolia, Turkey, is described, together with Bogidiella (Bogidiella) calicali Karaman, the latter being recorded for the first time in the eastern Mediterranean. A cladistic analysis of 37 Mediterranean species of the family Bogidiellidae is performed, using 4 species from the Canary Islands as an outgroup. Alternatively, 2 cladistic software packages, PAUP 3.1.1 and HENNIG86, are employed to calculate consensus trees of minimal length. The resulting trees show more or less identical robust clades, characterizing a central, a central-eastern, …

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Factors Affecting The Recruitment Of Juvenile Caribbean Spiny Lobsters Dwelling In Macroalgae, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt Jan 1997

Factors Affecting The Recruitment Of Juvenile Caribbean Spiny Lobsters Dwelling In Macroalgae, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt

Biological Sciences Faculty Publications

In south Florida, Caribbean spiny lobsters (Panulirus argus) settle and spend their first few months in macroalgae or seagrass. After a few months, these ''algal-phase'' juveniles emerge from vegetation and, as ''postalgal-phase'' juveniles, seek refuge in crevices, often dwelling in groups. The importance of crevice shelters in determining the abundance of postalgal-phase juvenile spiny lobsters has been studied but we know little about the processes affecting lobster distribution and survival during their cryptic algal-dwelling phase. We found that postlarval supply varied independently of changes in the structure of macroalgal settlement habitat. For this reason, postlarval supply alone can not reliably …

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Small-Scale Settlement Patterns Of The Oyster Crassostrea Virginica On A Constructed Intertidal Reef, Ian K. Bartol, Roger Mann Jan 1997

Small-Scale Settlement Patterns Of The Oyster Crassostrea Virginica On A Constructed Intertidal Reef, Ian K. Bartol, Roger Mann

Biological Sciences Faculty Publications

The construction of three-dimensional, intertidal reefs resembling those widely present during colonial times in the Chesapeake Bay, but now absent due to years of overharvesting, may provide a more ecologically advantageous environment for oyster settlement and subsequent survival than present subtidal, two-dimensional habitats. We examined settlement processes on a constructed, 210 x 30 m intertidal reef composed of oyster shell. The reef was destructively and non-destructively sampled weekly throughout the summer and fall at tidal heights ranging from 30 cm above to 90 cm below mean low water (MLW) and at two substrate levels (reef surface and 10 cm below …

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Cascading Disturbances In Florida Bay, Usa: Cyanobacteria Blooms, Sponge Mortality, And Implications For Juvenile Spiny Lobsters Panulirus Argus, Mark J. Butler Iv, John H. Hunt, William F. Herrnkind, Michael J. Childress, Rodney Bertelsen, William Sharp, Thomas Matthews, Jennifer M. Field, Harold G. Marshall Dec 1995

Cascading Disturbances In Florida Bay, Usa: Cyanobacteria Blooms, Sponge Mortality, And Implications For Juvenile Spiny Lobsters Panulirus Argus, Mark J. Butler Iv, John H. Hunt, William F. Herrnkind, Michael J. Childress, Rodney Bertelsen, William Sharp, Thomas Matthews, Jennifer M. Field, Harold G. Marshall

Biological Sciences Faculty Publications

Florida Bay, the shallow lagoon separating mainland Florida and the Florida Keys, USA, is experiencing an unprecedented series of ecological disturbances. In 1991, following reports of other ecosystem perturbations, we observed widespread and persistent blooms of cyanobacteria that coincided with the decimation of sponge communities over hundreds of square kilometers. Juvenile Caribbean spiny lobsters Panulirus argus, among other animals, rely on sponges for shelter; the impact of sponge loss on the abundance of lobsters and their use of shelter, in particular, has been dramatic. The loss of sponges on 27 experimental sites in hard bottom habitat in central Florida Bay …

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Scleractinian Corals Of Kuwait, G. Hodgson, Kent E. Carpenter Jan 1995

Scleractinian Corals Of Kuwait, G. Hodgson, Kent E. Carpenter

Biological Sciences Faculty Publications

A survey was made of the coral reefs of Kuwait to compile a species list of scleractinian corals. Twenty-eight hermatypic and six ahermatypic coral species are listed in systematic order, and a brief description is provided for each. A new species of Acropora is described. The Kuwait fauna is a small subset of the over 500 Indo-Pacific species. Several species show a higher degree of intraspecific variation than they exhibit in other locations. A range extension is reported for Acanthastrea maxima Sheppard & Salm, previously recorded from Oman (north and south coasts). A common species in the Arabian Gulf, Porites …

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Population-Dynamics Of Juvenile Caribbean Spiny Lobster, Panulirus-Argus, In Florida Bay, Florida, David Forcucci, Mark J. Butler Iv, John H. Hunt Jan 1994

Population-Dynamics Of Juvenile Caribbean Spiny Lobster, Panulirus-Argus, In Florida Bay, Florida, David Forcucci, Mark J. Butler Iv, John H. Hunt

Biological Sciences Faculty Publications

Despite a wealth of information on the growth and population dynamics of sub-adult and adult Caribbean spiny lobsters (Panulirus argus), there is far less information about younger juveniles under natural conditions. Here we describe growth and population dynamics of juvenile spiny lobsters (12-68 mm carapace length, CL) that we have studied for 14 months (October 1988-December 1989) using mark-recapture techniques in a hardbottom community in Florida Bay, Florida. We also monitored the supply of postlarvae into the region in 1988 and 1989 using Witham-type surface collectors in an effort to link peak periods of settlement of postlarvae with subsequent cohorts …

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Chesapeake Bay Phytoplankton: I. Composition, Harold G. Marshall Jan 1994

Chesapeake Bay Phytoplankton: I. Composition, Harold G. Marshall

Biological Sciences Faculty Publications

A list of 708 Phytoplankton taxa from 10 algal divisions has been compiled for the Chesapeake Bay and is based on the analysis of 2384 water samples over three decades of study.

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Observations On The Pearl Oyster Fishery Of Kuwait, S. M. Almatar, Kent E. Carpenter, R. Jackson, S. H. Alhazeem, A. H. Alsaffar, A. R. A. Ghaffar, C. Carpenter Jan 1993

Observations On The Pearl Oyster Fishery Of Kuwait, S. M. Almatar, Kent E. Carpenter, R. Jackson, S. H. Alhazeem, A. H. Alsaffar, A. R. A. Ghaffar, C. Carpenter

Biological Sciences Faculty Publications

The pearl oyster fishery of Kuwait was monitored daily from January 1989 to May 1990. Landings of pearl oysters in 1989 totaled 287 tons with a market value of U.S. $1.0 million. Commercial pearls (>3 mm) were estimated to be present in one of every 4200 oysters. Most of the pearl oysters landed were new recruits with hinge lengths between 40-56 mm. There was a curvilinear relationship between total weight and size of oysters (length) and the sex ratio approached 1:1. Spawning occurs throughout the year, with a spat settlement peak in early fall. Over the size range examined …

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Seasonal Phytoplankton Development Within Three Rivers In The Lower Chesapeake Bay Region, Harold G. Marshall, Lewis F. Affronti Jan 1992

Seasonal Phytoplankton Development Within Three Rivers In The Lower Chesapeake Bay Region, Harold G. Marshall, Lewis F. Affronti

Biological Sciences Faculty Publications

The seasonal and inter-annual concentrations of phytoplankton were studied over a 50 month period in the lower James, York and Rappahannock Rivers (USA). Differences in the onset, duration and magnitude of major seasonal growth periods varied from year to year. There was a tendency for spring, summer and fall maxima, with a winter period of reduced abundance. An additional study of picoplankton over a 12 month period indicated greatest abundance during summer and fall, with least development in winter.

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Spiny Lobster Recruitment In South Florida: Quantitative Experiments And Management Implications, Mark J. Butler Iv, William F. Herrnkind Jan 1992

Spiny Lobster Recruitment In South Florida: Quantitative Experiments And Management Implications, Mark J. Butler Iv, William F. Herrnkind

Biological Sciences Faculty Publications

Understanding recruitment and identifying factors critical to that process are imperative if adult spiny lobster Panulirus argus stocks are to be conserved and properly managed. The goal of our research has been to obtain ecological information linking inshore postlarval spiny lobster recruitment to later life stages, thereby providing the basic framework for assessing and predicting adult stock. Since 1983, we have investigated various aspects of spiny lobster recruitment including: postlarval time-to-metamorphosis, postlarval/juvenile habitat selection and selection cues, postlarval/juvenile crypticity and susceptibility to predation, juvenile food preference and emigration, juvenile sociality, and the effect of habitat degradation (i.e., siltration) on postlarval/juvenile …

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Sediment Denitrification Potential In The Elizabeth River, Virginia, Surena Fazeli-Matin, Andrew S. Gordon, Harold G. Marshall Jan 1991

Sediment Denitrification Potential In The Elizabeth River, Virginia, Surena Fazeli-Matin, Andrew S. Gordon, Harold G. Marshall

Biological Sciences Faculty Publications

Sediment denitrification potential from two sites in the Elizabeth River estuary was studied over a nine-month period using the acetylene blockage method. Rates of microbial processes in this environment are of interest because of the high concentration of toxics present in some parts of the system. Highest rates were found in the highly polluted Southern Branch of the Elizabeth River with nitrate amended sediment ranging from 2-262 nmol N20/h per 20ml of sediment and exhibiting maximal rates during spring and fall. Rates in the Main Stem of the Elizabeth River were lower, with less than 1-85 nmol N …

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