Digital Commons Network^™

Rapid Quantification Of Biofouling With An Inexpensive, Underwater Camera And Image Analysis, Matthew R. First, Scott C. Riley, Kazi Aminul Islam, Victoria Hill, Jiang Li, Richard C. Zimmerman, Lisa A. Drake

Electrical & Computer Engineering Faculty Publications

To reduce the transport of potentially invasive species on ships' submerged surfaces, rapid-and accurate-estimates of biofouling are needed so shipowners and regulators can effectively assess and manage biofouling. This pilot study developed a model approach for that task. First, photographic images were collected in situ with a submersible, inexpensive pocket camera. These images were used to develop image processing algorithms and train machine learning models to classify images containing natural assemblages of fouling organisms. All of the algorithms and models were implemented in a widely available software package (MATLAB^©). Initially, an unsupervised clustering model was used, and three …

A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rachel D. Cavanagh, Eugene J. Murphy, Thomas J. Bracegirdle, John Turner, Cheryl A. Knowland, Stuart P. Corney, Walker O. Smith Jr., Claire M. Waluda, Nadine M. Johnston, Richard G. J. Bellerby, Eileen E. Hofmann

CCPO Publications

Increasing concern about the impacts of climate change on ecosystems is prompting ecologists and ecosystem managers to seek reliable projections of physical drivers of change. The use of global climate models in ecology is growing, although drawing ecologically meaningful conclusions can be problematic. The expertise required to access and interpret output from climate and earth system models is hampering progress in utilizing them most effectively to determine the wider implications of climate change. To address this issue, we present a joint approach between climate scientists and ecologists that explores key challenges and opportunities for progress. As an exemplar, our focus …

Geospatial Approaches To Support Pelagic Conservation Planning And Adaptive Management, L. M. Wedding, Sara M. Maxwell, D. Hyrenbach, D. C. Dunn, J. J. Roberts, D. Briscoe, E. Hines, P. N. Halpin

Biological Sciences Faculty Publications

Place-based management in the open ocean faces unique challenges in delineating boundaries around temporally and spatially dynamic systems that span broad geographic scales and multiple management jurisdictions, especially in the 'high seas'. Geospatial technologies are critical for the successful design of pelagic conservation areas, because they provide information on the spatially and temporally dynamic oceanographic features responsible for driving species distribution and abundance in the open ocean, the movements of protected species, and the spatial patterns of distribution of potential threats. Nevertheless, there are major challenges to implementing these geospatial approaches in the open ocean. This Theme Section seeks to …

Acclimation, Adaptation, Traits And Trade-Offs In Plankton Functional Type Models: Reconciling Terminology For Biology And Modelling, Kevin J. Flynn, Michael St. John, John A. Raven, David O. F. Skibinski, J. Icarus Allen, Aditee Mitra, Eileen E. Hofmann

CCPO Publications

We propose definitions in terminology to enhance ongoing collaborations between biologists and modellers on plankton ecology. Organism "functional type" should refer to commonality in ecology not biogeochemistry; the latter is largely an emergent property of the former, while alignment with ecology is also consistent with usage in terrestrial science. Adaptation should be confined, as in genetics, to consideration of species inter-generational change; most so-called "adaptive" plankton models are thus acclimative, modifying vital rates in response to stimuli. Trait trade-off approaches should ideally only be considered for describing intra-generational interactions; in applications between generations, and certainly between unrelated species, such concepts …

Evolution Of The Freshwater Sardinella, Sardinella Tawilis (Clupeiformes: Clupeidae), In Taal Lake, Philippines And Identification Of Iits Marine Sister-Species, Sardinella Hualiensis, Demian Willette, Kent E. Carpenter, Mudjekeewis Santos

Biological Sciences Faculty Publications

We identify the sister species of the world's only freshwater sardinella, Sardinella tawilis (Herre, 1927) of Taal Lake, Philippines as the morphologically-similar marine Taiwanese sardinella Sardinella hualiensis (Chu and Tsai, 1958). Evidence of incomplete lineage sorting and a species tree derived from three mitochondrial genes and one nuclear gene indicate that S. tawilis diverged from S. hualiensis in the late Pleistocene. Neutrality tests, mismatch distribution analysis, sequence diversity indices, and species tree analysis indicate populations of both species have long been stable and that the divergence between these two lineages occurred prior to the putative 18th century formation of Taal …

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Biological Sciences Faculty Publications

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …

Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall

Virginia Journal of Science

This study involves a phytoplankton summer/autumn survey in 46 Virginia lakes and reservoirs during 2010-2012. A total of 307 taxa were identified which included several filamentous and colonial cyanabacteria in bloom concentrations. With the exception of one natural lake, the other sites sampled represent impoundments created decades ago, with the majority presently classified as meso- or eutrophic. Among the cyanobacteria were 6 known toxin producers (Anabaena circinalis, Anabaena spiroides, Aphanizomenon flos-aquae, Cylindrospermopsis raciborskii, Limnothrix redekei, and Microcystis aeruginosa). The study characterizes phytoplankton populations in these aging freshwater habitats taken from a large number …

Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones

OES Faculty Publications

Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …

Δ13c Is A Signature Of Light Availability And Photosynthesis In Seagrass, Xingping Hu, David J. Burdige, Richard C. Zimmerman

OES Faculty Publications

We explored the role of light-saturated (carbon-limited) photosynthesis on δ¹³C of turtlegrass (Thalassia testudinum Banks ex Konig) populations from the clear, blue waters of the Great Bahama Bank and the turbid, green waters of Florida Bay using field observations and radiative transfer models. Consistent with numerous previous observations, leaf δ¹³C decreased significantly with water depth in both regions. However the δ¹³C for Bahamas turtlegrass was 3 parts per thousand heavier than that for Florida Bay turtlegrass at equivalent depths, and broadband irradiance explained even less of the δ¹³C variations than depth. Instead, leaf δ¹³C showed a stronger relationship to …

First Records Of Hypleurochilus Geminatus And Centropristis Philadelphica From Chesapeake Bay, Aimee D. Halvorson

Virginia Journal of Science

During the fall of 2007, Centropris philadelphica (rock seabass) and Hypleurochilus geminatus (Crested blenny) were collected from Chesapeake Bay. These captures are significant as they represent the first substantiated record of C. philadelphica from Chesapeake Bay and only the second and third validated records of H. geminatus. Additionally, the first record of H. geminatus from Chesapeake Bay was only recently recognized since the specimen had been previously misidentified as Parablennius marmoreus (seaweed blenny). The collection of seven individuals of H. geminatus in 2007, from two locations, indicates that the species may be resident within the Chesapeake Bay estuary.

Patterns Of Spiny Lobster (Panulirus Argus) Postlarval Recruitment In The Carribbean: A Crtr Project, Mark J. Butler Iv, Angela M. Mojica, Eloy Sosa-Cordero, Marines Millet, Paul Sanchez-Navarro, Miguel A. Maldonado, Juan Posada, Bladimir Rodriguez, Carlos M. Rivas, Adrian Oviedo, Marcio Arrone, Martha Prada, Nick Bach, Nilda Jimenez, Maria Del Carmen Garcia-Rivas, Kirah Forman, Donald C. Behringer Jr., Thomas Matthews, Claire Paris, Robert Cowen

Biological Sciences Faculty Publications

As part of the Coral Reef Targeted Research (CRTR) Program, a partnership between the Global Environment Facility and the World Bank, our research team examined the recruitment patterns of Caribbean spiny lobster (Panulirus argus) postlarvae among regions in the Caribbean, with a particular focus on Mesoamerica. Our goal was to collect comparable information on postlarval supply among regions and to provide data to test predictions of connectivity generated from a coupled biophysical oceanographic model of lobster larval dispersal. Here we present the results of the postlarval recruitment monitoring program. We monitored the catch of postlarvae on Witham-style collectors …

Substituting Otoliths For Chemical Analyses: Does Sagitta = Lapillus?, Nathan G. Smith, Cynthia M. Jones

OES Faculty Publications

Chemical analysis of fish otoliths has become an important technique in fisheries science with widespread applications. Most research up to this point has focused predominantly on sagittal otoliths, but the underlying assumptions may also apply to lapilli. The goal of this study was to determine whether lapilli and sagittae have the same otolith chemistry and whether one can be substituted for the other for solution-based chemical analysis in wild-captured fish. We compared the stable isotope chemistry (δ13C and δ18O) of paired sagittae and lapilli of juvenile spotted seatrout Cynoscion nebulosus collected from Chesapeake Bay seagrass beds in 2002. …

Circulation, Vol. 8, No. 1, Center For Coastal Physical Oceanography, Old Dominion University, Ann E. Gargett

CCPO Circulation

Spring 2001 issue of CCPO Circulation featuring article "Remarks from a New Arrival: Dr. Ann Gargett"

The Palmer Lter: A Long-Term Ecological Research Program At Palmer Station, Antarctica, Raymond C. Smith, Karen S. Baker, William R. Fraser, Eileen E. Hofmann, David M. Karl, John M. Klinck, Langdon B. Quetin, Barbara B. Prezelin, Robin M. Ross, Wayne Z. Trivelpiece, Maria Vernet

CCPO Publications

THE ANTARCTIC marine ecosystem-the assemblage of plants, animals, ocean, sea ice, and island components south of the Antarctic Convergence is among the largest readily defined ecosystems on Earth (36 X 106 km2 ) (Hedgpeth, 1977; Petit et al., 1991). This ecosystem is composed of an interconnected system of functionally distinct hydrographic and biogeochemical subdivisions (Treguer and Jacques, 1992) and includes open ocean, frontal regions, shelf-slope waters, sea ice, and marginal ice zones. Oceanic, atmospheric, and biogeochemical processes within this system are thought to be globally significant, have been infrequently studied, and are poorly understood relative to more accessible marine ecosystems …

Paleobathymetric Interpretation Of Pleistocene Sediments In The South Padre Island Area, Northwestern Gulf Of Mexico, Using Benthic Foraminiferal Morphology, Karen Ianthe Kruebbe-Belwood

OES Theses and Dissertations

This study tested the validity of using intraspecific variation in benthic foraminifera as a means for determining Pleistocene paleobathymetry. Canonical variate analysis was used as a means for determining visually undetectable but statistically significant differences in the morphology of selected species. Two species, Cassidulina subglobosa and Uvigerina peregrina, were collected from Pleistocene well cuttings from the northwest Gulf of Mexico. The canonical analysis involved comparing the intraspecific variation of these Pleistocene species to their counterparts occurring in the modern Gulf of Mexico, where intraspecific variation was previously analyzed and found to be sufficient to allow detection of bathymetric differences …

The Remipedia (Crustacea): A Study Of Their Reproduction And Ecology, Jill Yager

Biological Sciences Theses & Dissertations

Remipedes are an unusual group of troglobitic crustaceans that live exclusively in anchialine caves. Since their discovery in 1979, nine species have been described, seven of which are found in caves in the West Indies, one from the Yucatan peninsula of Mexico and one from the Canary Islands. Most of what is known about these animals has come mainly from taxonomic descriptions. Little has been published about their reproductive biology or ecology. The objectives of this dissertation were to investigate the reproductive biology and ecology of the remipedes inhabiting Sagittarius Cave on Grand Bahama Island, Bahamas.

Sagittarius Cave was chosen …

The Effects Of Siltation On Recruitment Of Spiny Lobsters, Panulirus Argus, William F. Herrnkind, Mark J. Butler, Richard A. Tankersley

Biological Sciences Faculty Publications

Fewer juvenile pinry lobsters were found in areas of the Florida Keys where their primary habitat was heavily silted as compared with similar, less silted habitat. Several hypotheses explaining this relationship were tested, and the time-to-metamorphosis was compared for settling pueruli within silted and nonsilted algae stands. Limited postlarval settlement and avoidance of silted algal habitats by juveniles, probably accounts for the paucity of young lobsters in heavily silted sites. In addition, although juvenile lobsters are nonselective predators, lower prey availability in silted algae probably promotes transciency which, in turn, causes increased mortality by predation while juveniles are exposed.

Factors Regulating Settlement And Microhabitat Use By Spiny Lobsters Panulirus Argus, William F. Herrnkind, Mark J. Butler Iv

Biological Sciences Faculty Publications

Clumps of highly-branched red algae Laurencia spp. serve as important settling habitat for postlarval spiny lobsters Panulirus argus and as residence for early benthic-stage juveniles. Given choice between the 2 most abundant macrophytes in Florida Bay, Laurencia spp. and the seagrass Thalassia testudinum, postlarval and juvenile lobsters chose Laurencia spp. Postlarvae apparently use intricate algal architecture as a cue for settlement, whereas juveniles use both architecture and food abundance in selecting habitat. In tethering experiments, predation on juvenile lobsters was very high on open sand, much reduced in algal clumps and seagrass, and lowest in dense algal meadows. Predation …

Changes In The Lower Chesapeake Bay Food-Chain In Presence Of The Sea Nettle Chrysaora-Quinquecirrha (Scyphomedusa), David Feigenbaum, Michael Kelly

OES Faculty Publications

The abundance of 4 levels of the lower Chesapeake Bay food chain (Chlorophyll a, herbivores, ctenophore Mnemiopsis leidyi, and Scyphomedusa Chrysaora quinquecirrha) were moni­tored twice weekly at 4 stations from May 10 through Sep 30, 1982 in the Lafayette and Elizabeth Rivers (Virginia). The herbivore standing stock, largely copepods, declined sharply in late May when M. Jeidyi appeared, but rebounded a month later when C. quinquecirrha medusae reduced the ctenophore population. Despite the additional presence of Aurelia aurita (Scyphomedusa) from Jul onward, herbivore abundance remained at moderate levels until the end of the study period. Phytoplankton abundance fluctuated …

The Effect Of Sea Nettle Abundance On The Food Chain Of The Lower Chesapeake Bay, Michael Glenn Kelly

OES Theses and Dissertations

The significance of sea nettle abundance on lower levels of the Chesapeake Bay food chain was examined in a field study and by the analysis of medusa gut contents. In the field study, the abundance of four levels of the food chain (Chlorophyll (a), copepods, the ctenophore Mnemiopsis leidyi, and the Schyphomedusa Chrysaora guinguecirrha) were monitored twice weekly at four stations from May 10 through September 30, 1982. The copepod standing stock declined sharply in late May when M. leidyi appeared, but rebounded a month later when C. guinguecirrha medusae reduced the ctenophore population. Despite the additional presence …

Macrobenthic Communities Of An Industrialized Seaport Ecosystem: The Southern Branch Of The Elizabeth River, Virginia, Steven D. Hawthorne

Biological Sciences Theses & Dissertations

Macrobenthic invertebrates of an industrialized seaport ecosystem were studied seasonally from October, 1977 through July, 1978. Five stations were selected along the Southern Branch of the Elizabeth River, Virginia. The stations ranged from an area of heavy industrialization to a non-urbanized environment. At each station, bottom water was measured for salinity, temperature, dissolved oxygen, and pH. Within each sampling area, macrobenthic infauna! invertebrates were collected from in and out of channel sites along with sediment samples for various types of physicochemical analysis.

Community structure was spatially homogeneous at station sites and throughout the stations along the River. Slightly acidic pH …

Effect Of The Chesapeake-Elizabeth Sewage Outfall Virginia Beach, Virginia On The Distribution And Ecology Of Benthic Foraminifera, James M. Bates Jr.

OES Theses and Dissertations

Sediment and bottom water samples from seven stations at the Chesapeake Elizabeth sewage outfall, Virginia Beach, Virginia were collected in order to evaluate the effect of the outfall on benthic foraminifera. The top centimeter of sediment was analyzed for living and total (live plus dead) foraminiferal densities, chlorophyll a, sediment grain size, ATP, percentage of silt and clay, and total organic carbon. Bottom water salinity, temperature, and ammonia were also analyzed.

Living foraminiferal density increased from March to July and with distance from the outfall. Total foraminiferal density also increased from March to July. The set of environmental variables was …

Seasonal Distribution And The Retention Of Some Decapod Crustacean Larvae Within The Chesapeake Bay, Virginia, Joseph William Goy

OES Theses and Dissertations

Planktonic stages or 45 genera and species or decapod larvae were identified and staged from samples taken over a three year period in the lower portion and entrance area or Chesapeake Bay. The distribution of each larval stage of the decapod crustaceans found in the bay was determined and from this, the extent of the respective breeding season was deduced. In 1975, samples were taken monthly from stations along a transect at the baymouth, both at the surface and bottom. Two stations were also occupied over the tidal cycle in daylight and darkness. Evidence is presented that larvae of some …

Urbanization And Environmental Change In Lynnhaven Estuary, Don W. Oswalt

OES Theses and Dissertations

The very minimal amounts of available urbanization data demonstrate that the number of residential dwellings in the Lynnhaven drainage basin increased sharply in the late 1950’s and early 1960's, and that the 1970 basin population density value of 1981 people per square mile is larger than all the burrough density values, except for the Virginia Beach burrough. Due to a lack of data, only qualitative changes in Lynnhaven’s marine environment can be noted. There is a strong suggestion of an increase in amounts of urban storm water run-off into Lynnhaven since 1937. A considerable amount of siltation has occurred since …

A Seasonal Distributional Survey Of The Epiphytic Diatoms Of The Outer Banks Region Of North Carolina With Respect To Temperature And Salinity, Charles Welles Belin Jr.

OES Theses and Dissertations

This study was initiated to investigate epiphytic diatoms at selected stations along the North Carolina coast and bay region. The relationships between these organisms and the season of the year and salinity and temperature of the water in which they were found are considered. The special affinity between the epiphytic diatoms and their host plants is also discussed. The specific data were analyzed statistically via linear correlation coefficients, graphs of least squares-best fit, and multiple linear regression analysis.

From the statistical tests, it was found that the mean number of epiphytic diatoms shows a significant multiple linear regression with respect …

The Annual Distribution And Stratification Of Phytoplankton At Aurora Lake, Portage County, Ohio, Harold G. Marshall

Biological Sciences Faculty Publications

A 13-month study of a hard-water lake in northeast Ohio has provided a quantitative and qualitative record of the seasonal changes of the phytoplankton. Maximum production occurred during the summer and winter periods. The summer pulse was dominated by the cyanophyte species: Microcystis aeruginosa, Anabaena spiroides, A. circinalis, and Aphanizomenon flosaquae. The dominants of the winter pulse were the diatoms Fragilaria crotomensis and Asterionella formosa, which formed separate peaks under an ice cover in December and January, respectively. The January development extended into March with the highest concentrations for the year Being reached at approximately …