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Full-Text Articles in Life Sciences

Wetlands In Our Backyard: A Review Of Wetland Types In Virginia State Parks, Kirsten Bauer, Benjamin K. Campbell Oct 2022

Wetlands In Our Backyard: A Review Of Wetland Types In Virginia State Parks, Kirsten Bauer, Benjamin K. Campbell

Virginia Journal of Science

Wetlands constitute a significant component of Virginia’s natural resources and heritage. Though historically they have been discounted—and often denigrated—the exceptional value of wetlands is currently growing in recognition and appreciation. In addition to the value provided by extracted resources and ecological regulation, wetlands also offer people the opportunity to enrich themselves through cultural, educational, and recreational pursuits. The state parks of Virginia provide access to a variety of ecosystems, including a wide array of wetland types. In this review, we document the diversity of wetlands in Virginia State Parks through a typology that groups wetland systems into the three principal …


The Diversity And Distribution Of Spiders (Arachnida: Araneae) Along An Outdoor – Indoor Habitat Gradient: Preliminary Findings From Piedmont Virginia, William Kish, Sujan Henkanaththegedara Oct 2019

The Diversity And Distribution Of Spiders (Arachnida: Araneae) Along An Outdoor – Indoor Habitat Gradient: Preliminary Findings From Piedmont Virginia, William Kish, Sujan Henkanaththegedara

Virginia Journal of Science

Although the United States supports a considerable diversity of spiders, some aspects of spider habitat use and niche specialization are poorly documented. Specifically, little attention has been given to explore how urban development affects the diversity and abundance of arthropods. We sampled spiders along an outdoor – indoor habitat gradient at Longwood University to understand the impact of urbanization on species diversity and abundance. We found 50 taxa of spiders belonging to 43 genera and 16 families. Overall, the most abundant spider family across three sampling sites was Araneidae (orb-weavers; 18.2%) followed by Lycosidae (wolf spiders; 14.8%), Salticidae (jumping spiders; …


Microhabitat Comparison Of Percina Roanoka (Roanoke Darter) And Percina Nevisense (Chainback Darter) In The Roanoke River, Dakota R. Spruill, Steven L. Powers Apr 2019

Microhabitat Comparison Of Percina Roanoka (Roanoke Darter) And Percina Nevisense (Chainback Darter) In The Roanoke River, Dakota R. Spruill, Steven L. Powers

Virginia Journal of Science

Snorkel observations of Percina roanoka and P. nevisense in the Roanoke River during summer months were followed by measuring current velocity, water depth, and substrate diameter at points of occupation. A total of 89 observations of P. roanoka and 81 observations of P. nevisense were compared using two-sample T-tests. Percina roanoka inhabited faster, shallower water than P. nevisense with the former found in a mean flow of 0.318 m/s and depth of 31.53 cm and the latter in a mean flow of 0.17 m/s and depth of 55.6 cm. Mean diameter of substrate at points of occupation did not differ …


Compositional Changes In Two Small Mammal Communities During Succession In Southeastern Virginia, Robert K. Rose, Robyn M. Nadolny, Jay Kiser, Stephen E. Rice, Heather Green Salamone, Jana Eggleston, Holly D. Gaff Jan 2018

Compositional Changes In Two Small Mammal Communities During Succession In Southeastern Virginia, Robert K. Rose, Robyn M. Nadolny, Jay Kiser, Stephen E. Rice, Heather Green Salamone, Jana Eggleston, Holly D. Gaff

Virginia Journal of Science

Changes in the composition of two small mammal communities were studied during 8 and 9 years of ecological succession in southern Chesapeake. Virginia. Using monthly live-trapping on grids of similar size and history since their abandonment as agricultural fields, we learned that house mice were early colonists on one grid but not the other. Two species of herbivorous rodent and the granivorous eastern harvest mouse were numerically dominant on both grids across the study. Some species disappeared early on one grid but persisted to the end at the other. The two arboreal small mammals, golden and white-footed mice, were most …


Habitat Use By Bats On The Upper Coastal Plain Of Virginia, A. Scott Bellows, Joseph C. Mitchell Oct 2017

Habitat Use By Bats On The Upper Coastal Plain Of Virginia, A. Scott Bellows, Joseph C. Mitchell

Virginia Journal of Science

We monitored bat activity on the upper Coastal Plain of Virginia using mist nets and acoustic detection (ANABAT) during April-October 2000 and April-August 2001. We classified forty sites into three forest-cover classes (pine forest, mixed pine, and hardwood forest) and three landscape-feature classes (permanent water, riparian corridor, and upland). We captured 406 bats (8 species) in mist nets; red bats (Lasiurus borealis; n = 281), big brown bats (Eptesicus fuscus; n = 47), and eastern pipistrelles (Pipistrellus subflavus; n = 36) were the most commonly captured species. We captured fewer than 30 individuals of …


Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone Jan 2017

Population Dynamics Of The Cotton Rat In Southeastern Virginia, Robert K. Rose, Heather Green Salamone

Virginia Journal of Science

Abstract

We used monthly live trapping for 2.5 years to evaluate the life-history features of the most common small mammal, Sigmodon hispidus (hispid cotton rat), in an old field at its northern limit of distribution on the Atlantic coast. Peak densities, achieved in late autumn or early winter, were among the highest recorded for the species and were more typical of marginal populations rather than of central ones. Unlike some other marginal populations, hispid cotton rats in eastern Virginia did not lose significant body mass over the winter (when few juveniles were present) and survival in winter was not significantly …


Local Avian Density Influences Risk Of Mortality From Window Strikes, Ann M. Sabo, Natasha D.G. Hagemeyer, Ally S. Lahey, Eric L. Walters Jan 2016

Local Avian Density Influences Risk Of Mortality From Window Strikes, Ann M. Sabo, Natasha D.G. Hagemeyer, Ally S. Lahey, Eric L. Walters

Biological Sciences Faculty Publications

Up to a billion birds die per year in North America as a result of striking windows. Both transparent and reflective glass panes are a cause for concern, misleading birds by either acting as invisible, impenetrable barriers to desired resources, or reflecting those resources over a large surface area. A high number of window strikes occur during migration, but little is known about the factors of susceptibility, or whether particular avian taxa are more vulnerable than others. We report on a study of window strikes and mist-netting data at the Virginia Zoological Park (Norfolk, Virginia, USA), conducted in the autumn …


Virginia’S Amphibians: Status, Threats And Conservation, Jennifer Sevin, John D. Kleopfer Oct 2015

Virginia’S Amphibians: Status, Threats And Conservation, Jennifer Sevin, John D. Kleopfer

Virginia Journal of Science

Virginia’s diverse environments support 84 amphibian species (anurans and caudates), making it the third highest state in terms of species richness. However, the Commonwealth matches the global trend in declining amphibian populations with over one-third of its amphibian species in conservation need. The Species of Greatest Conservation Need included in the most recent Virginia Wildlife Action Plan cut across amphibian families and ecoregions. It is challenging to ascertain the exact cause of most of the population declines. In one degree or another, all of the global threats to amphibians exist within Virginia’s borders. While an active research program on amphibians …


Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain Oct 2015

Forest Diversity And Disturbance: Changing Influences And The Future Of Virginia’S Forests, Christine J. Small, James L. Chamberlain

Virginia Journal of Science

The Virginia landscape supports a remarkable diversity of forests, from maritime dune woodlands, swamp forests, and pine savannas of the Atlantic Coastal Plain, to post-agricultural pine-hardwood forests of the Piedmont, to mixed oak, mesophytic, northern hardwood, and high elevation spruce-fir forests across three mountain provinces in western parts of the state. Virginia’s forests also have been profoundly shaped by disturbance. Chestnut blight, hemlock woolly adelgid, emerald ash borer, and other pests have caused declines or functional extirpation of foundation species. Invasive plants like multiflora rose, Oriental bittersweet, and Japanese stiltgrass threaten both disturbed and intact forests. Oaks and other fire-dependent …


Freshwater Mussels Of Virginia (Bivalvia: Unionidae): An Introduction To Their Life History, Status And Conservation, Jess W. Jones Oct 2015

Freshwater Mussels Of Virginia (Bivalvia: Unionidae): An Introduction To Their Life History, Status And Conservation, Jess W. Jones

Virginia Journal of Science

With 77 species, the mussel fauna of Virginia is one of the most diverse in the United States. Fifty-four species or ~70% of the state’s mussel fauna occurs in the rivers of the upper Tennessee River basin, especially in the Clinch and Powell rivers of southwestern Virginia. An additional 23 species reside in rivers of the Atlantic Slope, including the Potomac, Rappahannock, York, James and Chowan basins, and in the New River, a major tributary to the Ohio River. A total of 39 species or 51% of Virginia’s mussel fauna is listed as federally endangered, state endangered or state threatened. …


Breeding Birds Of Virginia, Bryan D. Watts Oct 2015

Breeding Birds Of Virginia, Bryan D. Watts

Virginia Journal of Science

Virginia supports a diverse community of breeding birds that has been the focus of investigation for more than 400 years. The avifauna reflects the latitudinal position of the state and the fact that the border extends from the Atlantic Ocean to the Appalachian Mountains. A total of 224 species have been recorded breeding in Virginia, 214 of which are extant. Twenty species have colonized the state since 1900 including 14 since 1950. Of all extant species, 102 (48%) are considered common at least somewhere in the state and 64 (30%) are rare to very rare. Diversity varies by physiographic region …


Status Of Plants In Virginia, Michael H. Renfroe Oct 2015

Status Of Plants In Virginia, Michael H. Renfroe

Virginia Journal of Science

OVERVIEW OF BOTANICAL DIVERSITY

Virginia possesses a unique and varied assemblage of plant life. There are 3,164 species, subspecies and varieties of plants in Virginia (Weakley et al. 2012). As classified by the Virginia Department of Conservation and Recreation’s Division of Natural Heritage (DCR-DNH), they form some 94 ecological groups and 317 community types across five distinct physiographic provinces: Coastal Plain, Piedmont, Blue Ridge, Ridge and Valley, and Appalachian Plateau. The state extends 469 miles from east to west and 201 miles north to south at the widest points, enclosing 42,326 square miles of territory. This diverse range of environmental …


Virginia’S Land Mammals: Past And Present, With Some Thoughts About Their Possible Future, John F. Pagels, Nancy D. Moncrief Oct 2015

Virginia’S Land Mammals: Past And Present, With Some Thoughts About Their Possible Future, John F. Pagels, Nancy D. Moncrief

Virginia Journal of Science

Mammals encountered today in Virginia’s forests and fields include native and nonnative species, feral populations, and free-ranging pets. We examine factors that have influenced Virginia’s terrestrial mammal fauna since the arrival of European colonists in the 1600s and some of the factors that are shaping the fauna today. We look in depth at changes since Handley and Patton’s (1947) first complete monograph on Virginia mammals and augment Linzey’s (1998) book, The Mammals of Virginia. We include current nomenclature, baseline information, and references to comprehensive literature. We discuss some of the current and developing anthropogenic factors that have impacted, or that …


Viewing The Status Of Virginia’S Environment Through The Lens Of Freshwater Fishes, Paul L. Angermeier, Michael J. Pinder Oct 2015

Viewing The Status Of Virginia’S Environment Through The Lens Of Freshwater Fishes, Paul L. Angermeier, Michael J. Pinder

Virginia Journal of Science

We summarize a range of topics related to the status of Virginia’s freshwater fishes, their reflection of environmental quality, and their contribution to human wellbeing. Since 1994 the list of extant Virginia fishes has lengthened from 210 species to 227 species, mostly due to taxonomic reorganizations. Virginia’s list of Species of Greatest Conservation Need currently contains 96 fish species, predominated by darters (32 species) and minnows (28 species). Increasing trends in species rarity and threats to fishes suggest that Virginia’s aquatic environment is becoming less hospitable for fishes. Prevailing anthropogenic threats to fishes include agriculture, urban development, mineral extraction, forestry, …


Blue Carbon In Freshwater / Brackish Marshes On The Barrier Islands Of Virginia Aboveground Net Primary Productivity And Carbon Pools, Emily Caitlin Adams Apr 2015

Blue Carbon In Freshwater / Brackish Marshes On The Barrier Islands Of Virginia Aboveground Net Primary Productivity And Carbon Pools, Emily Caitlin Adams

Biological Sciences Theses & Dissertations

"Blue carbon" is a relatively new concept describing carbon distributed tidally and sequestered via net production within coastal ecosystems, including seagrass beds, mangrove forests, and salt-water marshes. These systems sequester carbon at least 10 times faster than terrestrial systems. Fresh to brackish wetlands that receive irregular tidal influence due to overwash and storm events have not been typically studied as blue carbon systems. My objective was to quantify carbon pools within four interdunal fresh to brackish marshes on Hog Island, Virginia to determine their blue carbon potential. Marshes 1 and 2 were farthest from the ocean, below and above a …


Life-History Aspects Of Moxostoma Cervinum (Blacktip Jumprock) In The Roanoke River, Virginia, Dezarai A. Thompson, John S. Bentley, Steven L. Powers Jan 2015

Life-History Aspects Of Moxostoma Cervinum (Blacktip Jumprock) In The Roanoke River, Virginia, Dezarai A. Thompson, John S. Bentley, Steven L. Powers

Virginia Journal of Science

Life-history aspects of Moxostoma cervinum(Blacktip Jumprock) were identified using specimens from recent collections and the Roanoke College Ichthyological Collection. The largest specimen examined was a female 161.27 mm SL and 66 months of age. Spawning appears to occur in May, with a mean of 2477.6 oocytes (SD = 2825.3) up to 1.54 mm diameter in gravid females. Sexual maturity appears to occur by 1-2 years of age in males and 2-3 years of age in females. Male to female ratio was not significantly different from 1:1. Chironomidae composed the bulk of the diet; while detritus, Trichoptera, Ephemeroptera, and Acari …


Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall Apr 2014

Phytoplankton In Virginia Lakes And Reservoirs: Part Ii, Harold G. Marshall

Virginia Journal of Science

Phytoplankton composition from 16 Virginia lakes and reservoirs are discussed with emphasis on the dominant taxa, algal bloom producers, and potentially harmful species at these locations. This is a companion study to the more comprehensive publication regarding Virginia freshwater phytoplankton by Marshall (2013).


Phytoplankton In Virginia Lakes And Reservoirs, Harold G. Marshall Jan 2013

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 Jan 2013

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 …


Fecal Indicator Bacteria In Knitting Mill Creek With A Comparison Of Methods Used To Enumerate E. Coli, Manju Nagarajan Oct 2012

Fecal Indicator Bacteria In Knitting Mill Creek With A Comparison Of Methods Used To Enumerate E. Coli, Manju Nagarajan

OES Theses and Dissertations

This research seeks to evaluate the impact of an urban, multi-use neighborhood on the bacteriological quality of water in Knitting Mill Creek, a blind arm of the Lafayette River, a sub-estuary of the lower Chesapeake Bay. A principal objective was to determine the effects of rainfall, a surrogate for run-off, on water-column concentrations of fecal-indicator bacteria (FIB). I collected water samples weekly (September 2009-December 2010) and biweekly (January 2010-December 2011) at a storm-sewer outfall and a nearby marina and quantified their E. coli and enterococci concentrations using Colilert-18 and Enterolert, most-probable-number assays. In addition, I took monthly samples for these …


Life History Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Margaret Cook Lynott Oct 2012

Life History Of Stranded Bottlenose Dolphins (Tursiops Truncatus) In Virginia, Margaret Cook Lynott

Biological Sciences Theses & Dissertations

Little is known about the life history and overall ecology of bottlenose dolphins that strand in Virginia. In this study, I examined archived life history samples and stranding data from bottlenose dolphins found in Virginia waters to (1) develop growth curves based on ages from sectioned teeth, (2) document characteristics of male and female reproductive organs, and (3) define the relationship between age/length and presence of neonatal characteristics during the first year of life. The Gompertz growth model provided the best fit of growth data for stranded T. truncatus in Virginia. Length at birth and asymptotic length for males were …


Unusually High Body Mass In Virginia Meadow Voles, Sara B. Longtin, Robert K. Rose Jan 2012

Unusually High Body Mass In Virginia Meadow Voles, Sara B. Longtin, Robert K. Rose

Biological Sciences Faculty Publications

We used monthly capture-mark-recapture information to determine growth rates and life spans for 2 populations of meadow voles studied for 28 and 29 months in eastern Virginia in order to learn whether the exceptionally large body masses of some voles were due to rapid growth, long lives, or both. On 1 study grid, 64 males (19%) and 43 nonpregnant females (11%) were ≥70 g, with the largest male being 89 g. Mostly positive growth rates (averaging 1.1-3.9 g/month) were recorded, even in autumn and winter months, times when meadow voles are losing mass in northern populations, where most studies of …


Cyanobacteria Dominance In The Oligohaline Waters Of Back Bay, Virginia, Harold G. Marshall Jan 2012

Cyanobacteria Dominance In The Oligohaline Waters Of Back Bay, Virginia, Harold G. Marshall

Biological Sciences Faculty Publications

Back Bay and its flora have historically been influenced by the interaction of freshwater flow in combination with frequent intrusion of saline water into its basin. These events have resulted in a dynamic environmental setting influencing the abundance and composition of its phytoplankton community. Dominating these oligohaline waters is a diverse representation and high abundance of freshwater filamentous and colonial cyanobacteria. These include the nonheterocystous Planktolyngbya contorta, Planktolyngbya limnetica, and Pseudanabaena limnetica, taxa implicated as bloom producers in Bay waters with N:P molar ratios ranging from 23:1 to 74:1.


Rats As Forest Pests In Southeastern Virginia: Girdling By The Hispid Cotton Rat Sigmodon Hispidus As A Significant Source Of Mortality Of Loblolly Pines (Pinus Taeda) In A Successional Pine Forest, Robyn M. Nadolny Jul 2011

Rats As Forest Pests In Southeastern Virginia: Girdling By The Hispid Cotton Rat Sigmodon Hispidus As A Significant Source Of Mortality Of Loblolly Pines (Pinus Taeda) In A Successional Pine Forest, Robyn M. Nadolny

Biological Sciences Theses & Dissertations

The hispid cotton rat (Sigmodon hispidus) is a common field rodent throughout the southeastern US, where volunteer loblolly pine trees (Pinus taeda) invade open space and begin the process of ecological succession from field to pine forest. Recent analysis of the diet of S. hispidus indicates that loblolly pine bark is stripped and eaten during the winter months. In this study, we explored the extent of rodent girdling on a 1.23 ha grid in a successional pine forest in southeastern Virginia. During the winter of 2005 we observed damage to 65% of trees in our study area, with 98% …


Advertisement Call And Distribution Of The Treefrogs Hyla Chrysoscelis And Hyla Versicolor In Virginia, Joseph C. Mitchell, Christopher A. Pague Jan 2011

Advertisement Call And Distribution Of The Treefrogs Hyla Chrysoscelis And Hyla Versicolor In Virginia, Joseph C. Mitchell, Christopher A. Pague

Virginia Journal of Science

The gray treefrog complex consists of two sibling species that are indistinguishable morphologically, the diploid Hyla chrysoscelis and the tetraploid Hyla versicolor. Identification is possible in the field only by audio recognition of male advertisement call trill rates (pulses/second). During 1979-1983 we evaluated taped calls of these two species taken from 89 populations from throughout Virginia to map their respective ranges and to evaluate differences in call parameters. Hyla chrysoscelis occurs in the Coastal Plain, eastern and southern Piedmont, and in southwestern Virginia. Hyla versicoloroccurs in the Piedmont, Blue Ridge, and Ridge and Valley regions south to Wythe …


Foundational Checklist Of The Amphibians Of Wise County, Virginia, Sarah R.A. Davidson, David L. Chambers Oct 2010

Foundational Checklist Of The Amphibians Of Wise County, Virginia, Sarah R.A. Davidson, David L. Chambers

Virginia Journal of Science

The Appalachian Mountains are arguably home to the highest degree of amphibian diversity in the world, particularly caudate (salamander) biodiversity. Despite the high degree of amphibian endemism in the Appalachians, several regions remain unsurveyed for amphibian species. In addition to this knowledge gap, we are in the midst of alarming amphibian biodiversity loss. Thus, it is of the utmost importance to bridge this knowledge gap by conducting surveys before some of these amphibian species are lost. We surveyed Wise County (previously unsurveyed county in the Appalachian Mountains with no records existing in the primary literature) over two years to assess …


The Mosquito (Diptera: Culicidae) Fauna Of The Blackwater Ecological Preserve: Effects Of Prescribed Burns And Habitat Type On Mosquito Abundance And Distribution, Norman A. Grefe Lll Jul 2010

The Mosquito (Diptera: Culicidae) Fauna Of The Blackwater Ecological Preserve: Effects Of Prescribed Burns And Habitat Type On Mosquito Abundance And Distribution, Norman A. Grefe Lll

Biological Sciences Theses & Dissertations

While mosquitoes (Diptera: Culicidae) are among the most studied of insect groups, much remains unknown about their distribution and response to environmental impacts such as prescribed burns. Blackwater Ecological Preserve, located near Zuni, Virginia, is a relict long leaf pine barren, parts of which undergo periodic prescribed burns to maintain and restore this fire-dependent ecosystem. To assess the impact of prescribed burns on mosquito activity and to determine associations between seasonal patterns of adult mosquito activity and habitat type, CDC light traps baited with dry ice were set (rom late April through October at Blackwater Ecological Preserve during the 2005 …


Phytoplankton Blooms: Their Occurrence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton Oct 2009

Phytoplankton Blooms: Their Occurrence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton

Virginia Journal of Science

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates. The abundance threshold levels that would identify bloom status from a non-bloom presence were species specific, varied with the taxon's cell size, and ranged from ca. 10 to 104 cells mL-1. Among the most consistent sporadic bloom producers were the dinoflagellates Akashiwo …


Phytoplankton Blooms: Their Occurence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton Jan 2009

Phytoplankton Blooms: Their Occurence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton

Biological Sciences Faculty Publications

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates. The abundance threshold levels that would identify bloom status from a non-bloom presence were species specific, varied with the taxon's cell size, and ranged from ca. 10 to 10(4) cells mL(-1). Among the most consistent sporadic bloom producers were the dinoflagellates Akashiwo sanguinea, Cochlodinium …


Dinoflagellate Cysts Within Sediment Collections From The Southern Chesapeake Bay, And Tidal Regions Of The James, York, And Rappahannock Rivers, Virginia, David W. Seaborn, Harold G. Marshall Oct 2008

Dinoflagellate Cysts Within Sediment Collections From The Southern Chesapeake Bay, And Tidal Regions Of The James, York, And Rappahannock Rivers, Virginia, David W. Seaborn, Harold G. Marshall

Virginia Journal of Science

The upper 2 cm of sediment core samples from 70 stations in the tidal waters of three Virginia rivers and at 23 stations in the lower Chesapeake Bay were sampled for dinoflagellate cysts. The river sediment cysts were dominated by three common bloom producing species (Heterocapsa triquetra, Scrippsiella trochoidea, and Cochlodinium polykrikoides), whereas these were in low concentration on the Chesapeake Bay sediments which contained mainly dinoflagellate cysts of neritic and oceanic taxa. The mean sediment concentrations from stations in the James, York, and Rappahannock rivers were respectively 1174.8, 536.2, and 323.6 cysts g-1. The mean …