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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 9967

Copper concentrations in the upper Columbia River as a limiting factor in White Sturgeon recruitment and recovery

Currently there is little natural recruitment of white sturgeon (Acipenser transmontanus) in the Upper Columbia River located in British Columbia, Canada and Washington, USA. This review of life history, physiology, and behavior of white sturgeon, along with data from recent toxicological studies, suggest that trace metals, especially Cu, affect survival and behavior of early life stage fish. Sturg
Authors
Holly J. Puglis, Aida Farag, Christopher A. Mebane

Trends of litter decomposition and soil organic matter stocks across forested swamp environments of the southeastern US

A common idea in the discussion of soil carbon processes is that litter decomposition rates and soil carbon stocks are inversely related. To test this overall hypothesis, simultaneous studies were conducted of the relationship of environmental gradients to leaf and wood decomposition, buried cloth decomposition and percent soil organic matter in Taxodium distichum swamps across the Mississippi Riv
Authors
Beth A. Middleton

Carrying capacity of a population diffusing in a heterogeneous environment

The carrying capacity of the environment for a population is one of the key concepts in ecology and it is incorporated in the growth term of reaction-diffusion equations describing populations in space. Analysis of reaction-diffusion models of populations in heterogeneous space have shown that, when the maximum growth rate and carrying capacity in a logistic growth function vary in space, conditio
Authors
Don DeAngelis, Bo Zhang, Wei-Ming Ni, Yuanshi Wang

Malaclemys terrapin (Diamondback terrapin) Lepadomorph epibionts

Diamondback terrapins (Malaclemys terrapin) are distributed along the Atlantic and Gulf of Mexico (GoM) coasts of the U.S.A. (Hart et al. 2014. Conserv. Genet. DOI 10.1007/s10592-014-0563-6). Under consideration for listing in Florida and proposed for Appendix II listing by the U.S. at CoP16 (CITES), terrapin populations are declining in many parts of their range due to drowning in crab pots, road
Authors
Margaret Lamont, Daniel J. Catizone, Richard O'Connor, Robert Blais, Limarie Rodgriguez, Cathy Holmes

Benthic infaunal communities of Baltimore and Norfolk Canyons

The imperative for finding, cataloging, and understanding continental margin diversity derives from the many key functions, goods and services provided by margin ecosystems and by an increasingly deleterious human footprint on our continental slopes (Levin and Dayton 2009). Progress in seafloor mapping technology and direct observation has revealed unexpected heterogeneity, with a mosaic of habita
Authors
Craig M. Robertson, Jill Bourque, Amanda Demopoulos

Detection probabilities and site occupancy estimates for amphibians at Okefenokee National Wildlife Refuge

Abstract not supplied at this time
Authors
L.L. Smith, W.J. Barichivich, J.S. Staiger, Kimberly G. Smith, C. K. Dodd

Semiautomated process for enumeration of fishes from recreational-grade side-scan sonar imagery

The use of hydroacoustic techniques is increasing as scientists search for less invasive ways to monitor fish populations, and using recreational side‐scan sonar (SSS) imagery for monitoring has become more common in aquatic resource management over the last 15 years due in part to its low cost and user‐friendly interface. The time‐consuming nature of manually counting fish targets has limited the
Authors
Katelyn M Lawson, Josey Lee Ridgway, Andrew T. Mueller, Jacob Faulkner, Robin Calfee

2020 drought in New England

Below average and infrequent rainfall from May through September 2020 led to an extreme hydrologic drought across much of New England, with some areas experiencing a flash drought, reflecting its quick onset. The U.S. Geological Survey (USGS) recorded record-low streamflow and groundwater levels throughout the region. In September, the U.S. Department of Agriculture (2020) declared Aroostook Count
Authors
Pamela J. Lombard, Janet R. Barclay, Dee-Ann E. McCarthy

Mapping Phragmites australis live fractional cover in the lower Mississippi River Delta, Louisiana

In response to a co-occurring non-native scale infestation and Phragmites australis dieback in southeast Louisiana, normalized difference vegetation index (NDVI) satellite mapping was implemented to track P. australis condition in the lower Mississippi River Delta. While the NDVI mapping successfully documented relative condition changes, identification of cause required a quantitative-biophysical
Authors
Amina Rangoonwala, Rebecca J. Howard, Elijah W. Ramsey III

Underwater photographic reconnaissance and habitat data collection in the Florida Keys—A procedure for ground truthing remotely sensed bathymetric data

Bathymetric geoprocessing analyses of the Florida Reef Tract have provided insights into trends of seafloor accretion and seafloor erosion over time and following major storm events. However, bathymetric surveys sometimes capture manmade structures and vegetation, which do not represent the desired bare-earth data. Therefore, ground truthing is essential to maintain the most accurate bathymetric d
Authors
Zachery W. Fehr, Kimberly K. Yates

Mapping climate change resistant vernal pools in the northeastern U.S.

Vernal pools are seasonal wetlands that provide important breeding habitat for a variety of amphibian species. As future climate projections indicate warmer growing seasons and earlier seasonal increases in evapotranspiration, some managers of vernal pools have expressed concern that pools may dry earlier in the season, potentially interfering with completion of amphibian life cycles. In this cont
Authors
Jennifer M. Cartwright, Evan H. Campbell Grant

Decision context as an essential component of population viability analysis

Population viability analysis (PVA) is a widely used tool that applies demographic data in simulation frameworks to assess extinction risk for species or populations. It is used in diverse conservation applications, including evaluating management effectiveness, relative risk of threats, and potential changes to protective status (Beissinger & McCullough, 2002), and can be a critical tool for maki
Authors
Abigail Jean Lawson, Brian Folt, Anna Maureen Tucker, Francesca T. Erickson, Conor P. McGowan