Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 17 of 17

Full-Text Articles in Entire DC Network

Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler Jan 2017

Frontiers In Otolith Chemistry: Insights, Advances And Applications, B. D. Walther, K. E. Limburg, C. M. Jones, J. J. Schaffler

OES Faculty Publications

The rapid proliferation of publications employing chemical assays of fish hard parts, and otoliths in particular, has led to many novel insights into the migration patterns, life history strategies and mixed stock dynamics of fishes across the globe (Campana et al., 2000; Elsdon et al., 2008; Walther & Limburg, 2012). These insights include uncovering diverse migratory strategies within species and populations (Kerr et al., 2009; Hogan et al., 2014; Schoen et al., 2016), quantifying rates of mixing among stocks across management boundaries (Rooker et al., 2008; Walther & Thorrold, 2010) and estimating the relative …


Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler Jan 2017

Beyond Zar: The Use And Abuse Of Classification Statistics For Otolith Chemistry, C. M. Jones, M. Palmers, J. J. Schaffler

OES Faculty Publications

Classification method performance was evaluated using otolith chemistry of juvenile Atlantic menhaden Brevoortia tyrannus when assumptions of data normality were met and were violated. Four methods were tested [linear discriminant function analysis (LDFA), quadratic discriminant function analysis (QDFA), random forest (RF) and artificial neural networks (ANN)] using computer simulation to determine their performance when variable-group means ranged from small to large and their performance under conditions of typical skewness to double the amount of skewness typically observed. Using the kappa index, the parametric methods performed best after applying appropriate data transformation, gaining 2% better performance with LDFA performing slightly better …


Regional Patterns In The Otolith Chemistry Of Juvenile Spotted Seatrout (Cynoscion Nebulosus) Differ Under Contrasting Hydrological Regimes, Chet F. Rakocinski, Bruce H. Comyns, Mark S. Peterson, Alan M. Shiller Feb 2015

Regional Patterns In The Otolith Chemistry Of Juvenile Spotted Seatrout (Cynoscion Nebulosus) Differ Under Contrasting Hydrological Regimes, Chet F. Rakocinski, Bruce H. Comyns, Mark S. Peterson, Alan M. Shiller

Faculty Publications

The value of using otolith chemistry to characterize recruitment in terms of natal source regions depends on how consistently spatio-temporal variation can be resolved. The objective of this study was to compare regional classification patterns in the otolith chemistry of juvenile Spotted Seatrout (Cynoscion nebulosus) between two years experiencing disparate hydrological regimes, and separated by a five year interlude. Spatial patterns in the whole-otolith chemistry of juveniles of this estuarine-dependent species were compared between years using five otolith elements and two stable isotopes. Consistent size-related trends in uptake and deposition were evidenced by parallel ontogenetic relationships for six otolith variables. …


Lack Of Equivalence In The Elemental And Stable Isotope Chemistry Within The Sagittal Otolith Pair Of The Summer Flounder, Paralichthys Dentatus, Antranik Kajajian, Jason J. Schaffler, Cynthia M. Jones Jan 2014

Lack Of Equivalence In The Elemental And Stable Isotope Chemistry Within The Sagittal Otolith Pair Of The Summer Flounder, Paralichthys Dentatus, Antranik Kajajian, Jason J. Schaffler, Cynthia M. Jones

OES Faculty Publications

In fish that are not bilaterally symmetrical, the left and right sagittae are often not symmetrical, exhibiting divergent growth patterns and mass, and may have differences in chemical composition. We investigated this in the asymmetrical summer flounder Paralichthys dentatus, collected from different nursery habitats along the US east coast. Significant differences were detected in otolith mass, δ13C, δ18O, Li:Ca, Mg:Ca, and Sr:Ca, and overall chemical signatures. These results refute the hypothesis of left-right equivalence that is prevalent for bilaterally symmetrical fishes. We tested whether a specific side was better suited for classification. The best models …


The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead Jan 2014

The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead

OES Theses and Dissertations

Understanding the population structure and patterns of connectivity in marine fishes is essential when making predictions about a species' resiliency and persistence in an increasingly changing environment. The Atlantic Menhaden Brevoortia tyrannus is a clupeid that plays a critical role in the marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before recruiting to the adult population and the contribution of each of …


Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones Jan 2013

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 …


Evaluating Methods For Optimizing Classification Success From Otolith Tracers For Spotted Seatrout (Cynoscion Nebulosus) In The Chesapeake Bay, Stacy Kavita Beharry Jan 2011

Evaluating Methods For Optimizing Classification Success From Otolith Tracers For Spotted Seatrout (Cynoscion Nebulosus) In The Chesapeake Bay, Stacy Kavita Beharry

OES Theses and Dissertations

Identifying the natal sources of fish is an important step in understanding its population dynamics. Adult recruits are often sourced from multiple nursery areas, with good quality locations contributing disproportionately more fish to the adult stock. Because population persistence is strongly influenced by nursery habitat, methods that correctly identify the source of recruits are necessary for effective management. Within the last decade, otolith chemistry signatures have been increasingly used as a natural marker to delineate fish from a mixture of nursery sources. Despite the widespread use of otolith trace element and stable isotope ratios as habitat markers, the statistical approaches …


Nitrogen Isotope Dynamics Of The Cariaco Basin, Venezuela, Robert C. Thunell, Daniel M. Sigman, Frank E. Muller-Karger, Yrene Astor, Ramon Varela Sep 2004

Nitrogen Isotope Dynamics Of The Cariaco Basin, Venezuela, Robert C. Thunell, Daniel M. Sigman, Frank E. Muller-Karger, Yrene Astor, Ramon Varela

Marine Science Faculty Publications

We report 15N/14N measurements of water column nitrate and ammonium, sinking particles, and sediments from the Cariaco Basin, an anoxic marine basin off the coast of Venezuela. Water column denitrification occurring in the basin has only a very small isotopic imprint on nitrate in the basin because nitrate consumption is nearly complete in the actively denitrifying water near the oxic/anoxic interface (∼275 m). Being free of a large denitrification signal, the δ15N of shallow thermocline nitrate is ∼3.5‰, significantly lower than the mean deep ocean nitrate δ15N of 5‰. This may be due …


Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett Nov 1998

Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett

OES Faculty Publications

We investigated the ability of trace element and isotopic signatures in otoliths to record the nursery areas of juvenile (young-of-the-year) weakfish Cynoscion regalis from the east coast of the USA. Juvenile C. regalis were captured with otter trawls at multiple sites in Doboy Sound (Georgia), Pamlico Sound (North Carolina), Chesapeake Bay (Virginia), Delaware Bay (Delaware) and Peconic Bay (New York), from July to September 1996. One sagittal otolith from each specimen was assayed for Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca ratios using inductively coupled plasma mass spectrometry (ICP-MS), while delta 13 C and delta 18 O values from the other sagittal …


Chemical Fate Of Bunker C Fuel Oil In A Subtropical Marine Environment Following A Spill In Tampa Bay, Florida, Dana Lynn Wetzel Jul 1995

Chemical Fate Of Bunker C Fuel Oil In A Subtropical Marine Environment Following A Spill In Tampa Bay, Florida, Dana Lynn Wetzel

USF Tampa Graduate Theses and Dissertations

A hydrocarbon chemistry study was performed on sediments, oil masses and mangrove prop roots of a mangrove island in Boca Ciega Bay, Florida following a spill of Bunker C fuel oil in Tampa Bay. Normal alkane (n-alkane) and polycylic aromatic hydrocarbon (PAH) profiles were monitored for effects of degradation and weathering in these mediums for a period of one year. Initial findings indicated a loss of lower molecular weight n-alkanes and PAH's in sediments and prop roots. There was little or no loss of these low molecular weight components in the oil mass samples. Hydrocarbon profiles at the end of …


School Of Marine Science Graduate Program 1993-94, College Of William And Mary, School Of Marine Science Aug 1993

School Of Marine Science Graduate Program 1993-94, College Of William And Mary, School Of Marine Science

Miscellaneous

Catalog for the Graduate program of the School of Marine Science at the College of William and Mary for the listed academic year.


School Of Marine Science Graduate Catalog 1992-93, College Of William And Mary, School Of Marine Science Aug 1992

School Of Marine Science Graduate Catalog 1992-93, College Of William And Mary, School Of Marine Science

Miscellaneous

Catalog for the Graduate program of the School of Marine Science at the College of William & Mary for the listed academic year.


School Of Marine Science Graduate Program Catalog 1991-92, College Of William And Mary, School Of Marine Science Aug 1991

School Of Marine Science Graduate Program Catalog 1991-92, College Of William And Mary, School Of Marine Science

Miscellaneous

Catalog for the Graduate program of the School of Marine Science at the College of William and Mary for the listed academic year.


School Of Marine Science Graduate Program Catalog 1990-91, College Of William And Mary, School Of Marine Science Aug 1990

School Of Marine Science Graduate Program Catalog 1990-91, College Of William And Mary, School Of Marine Science

Miscellaneous

Catalog for the Graduate program of the School of Marine Science at the College of William and Mary for the listed academic year.


Effects Of A Dispersed And Undispersed Crude Oil On Mangroves, Seagrasses And Corals, T. G. Ballou, Richard E. Dodge, S. C. Hess, A. H. Knap, Thomas D. Sleeter Oct 1987

Effects Of A Dispersed And Undispersed Crude Oil On Mangroves, Seagrasses And Corals, T. G. Ballou, Richard E. Dodge, S. C. Hess, A. H. Knap, Thomas D. Sleeter

Marine & Environmental Sciences Faculty Reports

The primary objective of this study was to evaluate the application of dispersant to spilled oil as a means of reducing adverse environmental effects of oil spills in nearshore, tropical waters. The results of numerous laboratory and field studies have suggested that dispersants may play a useful role in reducing adverse impacts on sensitive and valued environments such as mangroves, seagrasses, and corals. However, the use of dispersants has not been allowed thus far in most situations because of a lack of direct experimental data on the various effects of dispersants and the environmental trade-offs presumed to occur as a …


Tropical Oil Pollution Investigations In Coastal Systems (Tropics): Final Report, T. G. Ballou, Richard E. Dodge, S. C. Hess, A. H. Knap, T. D. Sleeter Jan 1987

Tropical Oil Pollution Investigations In Coastal Systems (Tropics): Final Report, T. G. Ballou, Richard E. Dodge, S. C. Hess, A. H. Knap, T. D. Sleeter

Marine & Environmental Sciences Faculty Reports

No abstract provided.


Variations In Some Serum Constituents Of The Blue Crab, Callinectes Sapidus, Maurice P. Lynch Jan 1972

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

Dissertations, Theses, and Masters Projects

No abstract provided.