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Publications

Read publications and other informational products to learn more about USGS science occurring in the Mississippi Basin.

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White perch health relative to urbanization and habitat degradation in Chesapeake Bay tributaries. I. Biliary neoplasms and hepatic lesions White perch health relative to urbanization and habitat degradation in Chesapeake Bay tributaries. I. Biliary neoplasms and hepatic lesions

White perch Morone americana (Gmelin, 1789) from the Chesapeake Bay (USA) watershed have a high incidence of liver disease, including neoplasms of bile duct origin. Fish collected seasonally from spring 2019 to winter 2020 from the urban Severn River and the more rural Choptank River were evaluated for hepatic lesions. Biliary hyperplasia (64.1%), neoplasms (cholangioma and...
Authors
Vicki S. Blazer, Mark A Matsche, Erin L. Pulster

Evolution of a minimal cell Evolution of a minimal cell

Possessing only essential genes, a minimal cell can reveal mechanisms and processes that are critical for the persistence and stability of life1,2. Here we report on how an engineered minimal cell3,4 contends with the forces of evolution compared with the Mycoplasma mycoides non-minimal cell from which it was synthetically derived. Mutation rates were the highest among all reported...
Authors
Roy Z. Moger-Reischer, John I. Glass, Kim S. Wise, Lijie Sun, Daniela Bittencourt, Brent K. Lehmkuhl, Donald Schoolmaster, Michael Lynch, Jay T. Lennon

Identifying invertebrate indicators for streamflow duration assessments in forested headwater streams Identifying invertebrate indicators for streamflow duration assessments in forested headwater streams

Streamflow-duration assessment methods (SDAMs) are rapid, indicator-based tools for classifying streamflow duration (e.g., intermittent vs perennial flow) at the reach scale. Indicators are easily assessed stream properties used as surrogates of flow duration, which is too resource intensive to measure directly for many reaches. Invertebrates are commonly used as SDAM indicators because...
Authors
Ken M. Fritz, Roxolana O. Kashuba, Gregory J. Pond, Jay R. Christensen, Laurie C. Alexander, Benjamin J. Washington, Brent R. Johnson, David Walters, William T. Thoeny, Paul C. Weaver

Presence of hummock and hollow microtopography reflects shifting balances of shallow subsidence and root zone expansion along forested wetland river gradients Presence of hummock and hollow microtopography reflects shifting balances of shallow subsidence and root zone expansion along forested wetland river gradients

Tidal freshwater forested wetlands (TFFWs) are in an active phase of transition to tidal marsh with sea level rise and salinity incursion along the Atlantic and Gulf Coasts of the United States (U.S.). A prominent feature of TFFWs is hummock/hollow microtopography where hollows represent the flat, base-elevation of the floodplain where inundation occurs relatively frequently, while...
Authors
Ken Krauss, Gregory E. Noe, Jamie A. Duberstein, Nicole Cormier, Andrew From, Thomas Rossiter Doody, William H. Conner, Donald R. Cahoon, Darren Johnson

2023 Coastal master plan: ICM-wetlands – Submerged aquatic vegetation (SAV) updates 2023 Coastal master plan: ICM-wetlands – Submerged aquatic vegetation (SAV) updates

Submerged aquatic vegetation (SAV) provides critical structural habitat for valuable nekton and wildlife species across coastal ecosystems and can buffer the negative effects of land loss. Landscape change and restoration efforts across coastal Louisiana can impact the occurrence, coverage, and species assemblages of SAV, and changes to these foundational species can have cascading...
Authors
Kristin DeMarco, Donald Schoolmaster, Brady Couvillion

2023 Coastal master plan: Landscape input data 2023 Coastal master plan: Landscape input data

Coastal Louisiana is a complex landscape. The composition of the landscape, as well as the processes which influence said landscape, vary in both space and time. The models used in the 2023 Coastal Master Plan must attempt to reflect that spatial and temporal variability. It is therefore of the utmost importance that the spatial data sets upon which the models are initialized are of the...
Authors
Brady Couvillion

Assessing impacts of human stressors on stream fish habitats across the Mississippi River basin Assessing impacts of human stressors on stream fish habitats across the Mississippi River basin

Effective conservation of stream fishes and their habitats is complicated by the fact that human stressors alter the way in which natural factors such as stream size, catchment geology, and regional climate influence stream ecosystems. Consequently, efforts to assess the condition of stream fishes and their habitats must not only attempt to characterize the effects of human stressors but...
Authors
Jared Ross, Dana M. Infante, Arthur R. Cooper, Joanna B. Whittier, Wesley Daniel

Modeling surface wave dynamics in upper Delaware Bay with living shorelines Modeling surface wave dynamics in upper Delaware Bay with living shorelines

Living shorelines gain increasing attention because they stabilize shorelines and reduce erosion. This study leverages physics-based models and bagged regression tree (BRT) machine learning algorithm to simulate wave dynamics at a living shoreline composed of constructed oyster reefs (CORs) in upper Delaware Bay. The physics-based models consist of coupled Delft3D-FLOW and SWAN in four...
Authors
Ling Zhu, Q. Chen, Hongqing Wang, Nan Wang, Kelin Hu, William D. Capurso, Lukasz M. Niemoczynski, Gregg Snedden

Herbivorous grass carp (Ctenopharyngodon idella) exhibit greater olfactory response to amino acids than filter-feeding bighead (Hypophthalmichthysnobilis) and silver carp (Hypophthalmichthys molitrix) Herbivorous grass carp (Ctenopharyngodon idella) exhibit greater olfactory response to amino acids than filter-feeding bighead (Hypophthalmichthysnobilis) and silver carp (Hypophthalmichthys molitrix)

Due to their invasiveness in North America, grass (Ctenopharyngodon idella), bighead (Hypophthalmichthys nobilis), and silver carp (Hypophthalmichthys molitrix) are management priorities. Comparing electrophysiological responses to olfactory cues, such as amino acids, could help identify stimuli to facilitate management efforts (i.e., repellants or baits). We assessed olfactory response...
Authors
Mark L. Wildhaber, Benjamin M West, Karlie K Ditter, Alex S. Peterson, Robin D. Calfee, Zachary D Beaman

Hydrogeomorphic changes along mid-Atlantic coastal plain rivers transitioning from non-tidal to tidal: Implications for a rising sea level Hydrogeomorphic changes along mid-Atlantic coastal plain rivers transitioning from non-tidal to tidal: Implications for a rising sea level

Sea level rise is affecting reaches of coastal rivers by increasing water levels and propagating tides inland. The transition of river systems into tidal estuaries has been neglected in hydrogeomorphic studies. A better understanding of transitioning reaches is critical to understanding ecosystem dynamics, services, and developing predictive capabilities of change as sea levels rise. We
Authors
Daniel Kroes, Gregory E. Noe, Cliff R. Hupp, Thomas Rossiter Doody, P.A. Bukaveckas

A new DNA extraction method (HV-CTAB-PCI) for amplification of nuclear markers from open ocean-retrieved faeces of an herbivorous marine mammal, the dugong A new DNA extraction method (HV-CTAB-PCI) for amplification of nuclear markers from open ocean-retrieved faeces of an herbivorous marine mammal, the dugong

Non-invasively collected faecal samples are an alternative source of DNA to tissue samples, that may be used in genetic studies of wildlife when direct sampling of animals is difficult. Although several faecal DNA extraction methods exist, their efficacy varies between species. Previous attempts to amplify mitochondrial DNA (mtDNA) markers from faeces of wild dugongs (Dugong dugon) have...
Authors
Vicky Ooi, Lee McMichael, Margaret Hunter, Aristide Takoukam Kamla, Janet M. Lanyon

Is chemical control for crayfish in hatchery fish shipments practical? Is chemical control for crayfish in hatchery fish shipments practical?

Invasive crayfish (family Cambaridae) displace native crayfish species and alter aquatic habitat, community structure, and ecosystem function. We evaluated whether chemical control can be a reliable control agent for crayfish to ensure that shipments from fish hatcheries did not result in new infestations of invasive crayfish. A series of acute (≤1 h) toxicity tests were conducted to...
Authors
Ann Allert, Daniel J. Westrich, David W. Whites, Katrina Knott, Nathan Storts, Robert J. DiStefano
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