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Dive into the research topics where Stuart A. Welsh is active.

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Featured researches published by Stuart A. Welsh.


Environmental Biology of Fishes | 1998

Habitat partitioning in a community of darters in the Elk River, West Virginia

Stuart A. Welsh; Sue A. Perry

Microhabitat use and habitat partitioning for 10 darter species (Percidae: Etheostomatini) were studied by direct observation (snorkeling) at five sites in the Elk River drainage, West Virginia, U.S.A. We used canonical discriminant analysis and univariate tests to determine microhabitat variables that were important in segregating species. Darter species were segregated by depth, substrate size, and water velocity. In addition, Percina typically occurred in the water column, whereas species of Etheostoma were benthic and segregated by occurring under, between, and on top of rocks.


Southeastern Naturalist | 2010

Distribution and Conservation Standing of West Virginia Crayfishes

Zachary J. Loughman; Stuart A. Welsh

Abstract The diversity of crayfishes in West Virginia represents a transition between the species-rich southern Appalachian faunas and the depauperate crayfish diversity in the northeastern United States. Currently, 22 described species occur in the state, of which 6 are given S1 status, and 3 are introduced species. One species, Orconectes limosus (Spinycheek Crayfish) is considered extirpated within the past decade. Imperiled species include Cambarus veteranus (Big Sandy Crayfish), Cambarus elkensis (Elk River Crayfish), Cambarus longulus (Atlantic Slope Crayfish), and Cambarus nerterius (Greenbrier Cave Crayfish). Three species—O. virilis (Virile Crayfish), Orconectes rusticus (Rusty Crayfish), and Procambarus zonangulus (Southern White River Crawfish)—have introduced populations within the state. Procambarus acutus (White River Crawfish) occurs in bottomland forest along the Ohio River floodplain, and is considered native. Several undescribed taxa have been identified and currently are being described. A statewide survey was initiated in 2007 to document the current distribution and conservation status of crayfishes in West Virginia.


Journal of Environmental Quality | 2009

Effects of highway construction on stream water quality and macroinvertebrate condition in a Mid-Atlantic Highlands watershed, USA.

Yushun Chen; Roger C. Viadero; Xinchao Wei; Ronald H. Fortney; Lara B. Hedrick; Stuart A. Welsh; James T. Anderson; Lian-Shin Lin

Refining best management practices (BMPs) for future highway construction depends on a comprehensive understanding of environmental impacts from current construction methods. Based on a before-after-control impact (BACI) experimental design, long-term stream monitoring (1997-2006) was conducted at upstream (as control, n = 3) and downstream (as impact, n = 6) sites in the Lost River watershed of the Mid-Atlantic Highlands region, West Virginia. Monitoring data were analyzed to assess impacts of during and after highway construction on 15 water quality parameters and macroinvertebrate condition using the West Virginia stream condition index (WVSCI). Principal components analysis (PCA) identified regional primary water quality variances, and paired t tests and time series analysis detected seven highway construction-impacted water quality parameters which were mainly associated with the second principal component. In particular, impacts on turbidity, total suspended solids, and total iron during construction, impacts on chloride and sulfate during and after construction, and impacts on acidity and nitrate after construction were observed at the downstream sites. The construction had statistically significant impacts on macroinvertebrate index scores (i.e., WVSCI) after construction, but did not change the overall good biological condition. Implementing BMPs that address those construction-impacted water quality parameters can be an effective mitigation strategy for future highway construction in this highlands region.


Estuaries | 2002

Distribution and movement of shortnose sturgeon (Acipenser brevirostrum) in the Chesapeake Bay

Stuart A. Welsh; Michael Mangold; Jorgen Skjeveland; Albert Spells

During a reward program for Atlantic sturgeon (Acipenser oxyrinchus), 40 federally endangered shortnose sturgeon (Acipenser brevirostrum) were captured and reported by commercial fishers between January 1996 and January 2000 from the Chesapeake Bay. Since this is more than double the number of published records of shortnose sturgeon in the Chesapeake Bay between 1876 and 1995, little information has been available on distributions and movement. We used fishery dependent data collected during the reward program to determine the distribution of shortnose sturgeon in the Chesapeake Bay. Sonically-tagged shortnose sturgeon in the Chesapeake Bay and Delaware River were tracked to determine if individuals swim through the Chesapeake and Delaware Canal. Shortnose sturgeon were primarily distributed within the upper Chesapeake Bay. The movements of one individual, tagged within the Chesapeake Bay and later relocated in the canal and Delaware River, indicated that individuals traverse the Chesapeake and Delaware Canal.


Northeastern Naturalist | 2009

West Virginia Crayfishes (Decapoda: Cambaridae): Observations on Distribution, Natural History, and Conservation

Zachary J. Loughman; Thomas P. Simon; Stuart A. Welsh

Abstract West Virginias crayfishes have received moderate attention since publication of Jezerinac et al.s (1995) monograph of the state fauna. Survey efforts were initiated over the summers of 2006 and 2007 to gather voucher material for the Indiana Biological Surveys Crustacean Collection. These collections have provided new information regarding the distribution, natural history, life history, taxonomy, and conservation status of Cambarus (Cambarus) carinirostris, C. (C.) bartonii cavatus, C. (C.) sciotensis, C. (Hiaticambarus) chasmodactylus, C. (H.) elkensis, C. (H.) longulus, C. (Jugicambarus) dubius, C. (Puncticambarus) robustus, Orconectes (Procericambarus) cristavarius, and O. (P.) rusticus. Orconectes (Faxonius) limosus has apparently been extirpated from West Virginia and should be removed from the states list of extant crayfishes.


Copeia | 2001

Systematics of Etheostoma tippecanoe and Etheostoma denoncourti (Perciformes: Percidae)

Andrew P. Kinziger; Robert M. Wood; Stuart A. Welsh

Abstract Recently, populations of Etheostoma tippecanoe from the Tennessee River drainage were described as a new species, Etheostoma denoncourti. Although populations of E. tippecanoe from the lower Tennessee River (Duck and Buffalo Rivers) were assigned to the new taxon, the species description did not contain an analysis of specimens from these rivers. To evaluate the phylogenetic placement of these unanalyzed populations with respect to all other populations of E. tippecanoe and E. denoncourti, we assembled a dataset composed of DNA sequences (complete cytochrome b) from 32 individuals representing all known populations of these species. Parsimony analysis of these populations, 11 other darter taxa, and five outgroup taxa resulted in 3868 equally most-parsimonous trees at 1687 steps. Populations from the Duck and Buffalo Rivers were always resolved as members of the newly described taxon, E. denoncourti, consistent with the original description. Further, E. tippecanoe and E. denoncourti were resolved as monophyletic sister taxa in all most-parsimonious trees. The amount of cytochrome b sequence divergence separating these two taxa (5.63%) is within the range observed for cytochrome b variation between other species of darters.


Journal of Crustacean Biology | 2012

Occupancy Rates of Primary Burrowing Crayfish in Natural and Disturbed Large River Bottomlands

Zachary J. Loughman; Stuart A. Welsh; Thomas P. Simon

ABSTRACT Among crayfish, primary burrowing species are the least understood ecologically. Many primary burrowing crayfish inhabit floodplains where forested landscapes have been fragmented by agricultural, industrial, or residential uses. In this study, site occupancy rates (&psgr;) were modeled for two primary burrowing crayfish, Fallicambarus fodiens (Cottle, 1863) and Cambarus thomai Jezerinac, 1993, from Ohio and Kanawha river floodplains in West Virginia, U.S.A. Fallicambarus fodiens is one of West Virginias rarest crayfish, while C. thomai is prevalent in most wetlands along both river floodplains. Occupancy rate modeling incorporated four environmental covariates (forest age, soil type, tree frequency, and land use). Based on presence/absence data, forests with tree ages > 100 years (&Dgr;QAICc = 0) and sites with loam soils (&Dgr;QAICc = 1.80) were most likely to harbor F. fodiens populations. For C. thomai, several models were supported owing to model selection uncertainty, but those with the land use covariate had more total model weight (total wi = 0.54) than all other covariate models. Cambarus thomai rarely occupied industrial/agricultural sites, but were often present in forested and residential sites. Although the influence of covariates on site occupancy differed between species, both taxa readily utilized mature forested habitats when available. Conservation actions for F. fodiens and C. thomai should focus on preserving forested tracts along large river floodplains


Molecular Ecology Resources | 2008

PERMANENT GENETIC RESOURCES: Microsatellite DNA primers for the candy darter, Etheostoma osburni and variegate darter, Etheostoma variatum, and cross-species amplification in other darters (Percidae).

John F. Switzer; Stuart A. Welsh; Tim L. King

In order to investigate a potential hybrid zone between the candy darter, Etheostoma osburni, and variegate darter, Etheostoma variatum, and examine population variation within E. osburni, a suite of primers for 15 polymorphic microsatellite loci were developed. The average number of alleles per locus was 5.5 in E. osburni and 7.6 in E. variatum, and the average observed heterozygosities were 62.5% and 71.4%, respectively. There were no deviations from Hardy–Weinberg equilibrium and no observed linkage disequilibrium after Bonferroni correction. The utility of these primers was also tested in 11 species of darters representing all four genera of darters. Success of cross‐species amplification was largely consistent with phylogenetic relationships of darters.


Molecular Ecology Resources | 2008

Microsatellite DNA primers for the candy darter, Etheostoma osburni and variegate darter, Etheostoma variatum, and cross-species amplification in other darters (Percidae)

John F. Switzer; Stuart A. Welsh; Tim L. King

In order to investigate a potential hybrid zone between the candy darter, Etheostoma osburni, and variegate darter, Etheostoma variatum, and examine population variation within E. osburni, a suite of primers for 15 polymorphic microsatellite loci were developed. The average number of alleles per locus was 5.5 in E. osburni and 7.6 in E. variatum, and the average observed heterozygosities were 62.5% and 71.4%, respectively. There were no deviations from Hardy–Weinberg equilibrium and no observed linkage disequilibrium after Bonferroni correction. The utility of these primers was also tested in 11 species of darters representing all four genera of darters. Success of cross‐species amplification was largely consistent with phylogenetic relationships of darters.


Transactions of The American Fisheries Society | 2007

Tag-Based Estimates of Annual Fishing Mortality of a Mixed Atlantic Coastal Stock of Striped Bass

Stuart A. Welsh; David R. Smith; R. Wilson Laney; Ronald C. Tipton

Abstract Tag-based estimates of annual survival and fishing mortality rates supplement annual stock assessments of migratory striped bass Morone saxatilis in the interjurisdictional fishery along the Atlantic coast. We estimated a 17-year time series of annual survival and fishing mortality (F) rates for striped bass (>711 mm) tagged during winter trawl studies (1988–2004) off the coasts of North Carolina and Virginia. The geographic and temporal distributions of tag recoveries were consistent with published patterns of striped bass migration and indicated that this southern overwintering aggregate of striped bass is composed of mixed stocks. Incremental increases in bias-adjusted annual fishing mortality rates (from 0.00–0.26) and decreases in the proportion of fish released alive (from 0.762–0.198) coincided with periods of regulatory change during the 17-year time frame. Our estimates of F fall below the current management triggers and should be considered along with other estimates of F within the str...

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Kenneth R. Sheehan

University of New Hampshire

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John F. Switzer

United States Geological Survey

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