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Publications

Publications from USGS science centers throughout the Southeast Region.

Filter Total Items: 9967

Crocodylus acutus (American crocodile). Diet

Reported prey items of Crocodylus acutus include insects, crustaceans, fish, and large reptiles (Medem 1981. Los Crocodylia de Sur America. Volumen I. Los Crocodylia de Colombia. Colciencias. Bogota, Colombia. 398 pp.; Platt et al. 2002. Herpetol. Rev. 33:202–203; Platt et al. 2013. J. Herpetol. 47:1–10; Balaguera-Reina et al. 2018. Ecosphere 9:e02393). Recently, new potential prey items such as L
Authors
Sidney T. Godfrey, Michael Cherkiss, Jeffrey S. Beauchamp, Michiko A. Squires, Frank J. Mazzotti, Lindsey Hord, William Billings

Technical note—Performance evaluation of the PhytoFind, an in-place phytoplankton classification tool

In 2019, the U.S. Geological Survey evaluated the performance of the Turner Designs, Inc. PhytoFind, an in-place phytoplankton classification tool. The sensor was tested with sample blanks, monoculture and mixed phytoplankton cultures, and turbidity challenges in a laboratory, and was tested on a 120-mile survey of the Caloosahatchee and St. Lucie Rivers in Florida, including Lake Okeechobee. Resu
Authors
Brett D. Johnston, Jennifer L. Graham, Guy M. Foster, Bryan D. Downing

Wild bee exposure to pesticides in conservation grasslands increases along an agricultural gradient: A tale of two sample types

Conservation efforts have been implemented in agroecosystems to enhance pollinator diversity by creating grassland habitat, but little is known about the exposure of bees to pesticides while foraging in these grassland fields. Pesticide exposure was assessed in 24 conservation grassland fields along an agricultural gradient at two time points (July and August) using silicone band passive samplers
Authors
Michelle Hladik, Johanna M. Kraus, Cassandra Smith, Mark W. Vandever, Dana W. Kolpin, Carrie E Givens, Kelly L. Smalling

New larger benthic foraminifera from the subsurface Lower to Middle Eocene Oldsmar Formation of southeastern Florida (USA)

We describe two larger benthic foraminiferal taxa collected from wells drilled in the subsurface Eocene rocks of southeastern Florida that are new to peninsular Florida and the Caribbean region. Saudia floridana n.sp. is characteristic of a foraminiferal assemblage, along with Helicostegina gyralis, wide forms of the Cushmania americana group, and Gunteria floridana, in an upper part of the Oldsma
Authors
Edward Robinson, Kevin J. Cunningham

Analysis of per capita contributions from a spatial model provides strategies for controlling spread of invasive carp

Metapopulation models may be applied to inform natural resource management to guide actions targeted at location-specific subpopulations. Model insights frequently help to understand which subpopulations to target and highlight the importance of connections among subpopulations. For example, managers often treat aquatic invasive species populations as discrete populations due to hydrological (e.g.
Authors
Donald Schoolmaster, Alison A. Coulter, Jahn L. Kallis, David C. Glover, John M. Dettmers, Richard A. Erickson

Comparison of two estrogen chemically activated luciferase expression cell bioassays to liquid chromatography–mass spectrometry for quantifying estrone in water samples

Chemically activated luciferase expression (CALUX) cell bioassays are popular tools for assessing endocrine activity of chemicals such as certain environmental contaminants. Although activity equivalents can be obtained from CALUX analysis, directly comparing these equivalents to those obtained from analytical chemistry methods can be problematic because of the complexity of endocrine active pathw
Authors
Jennifer C. Brennan, Abigail Henke, Robert Gale, Diane K. Nicks, Donald Tillitt

Soil elevation change in mangrove forests and marshes of the greater Everglades: A regional synthesis of surface elevation table-marker horizon (SET-MH) data

Coastal wetlands adapt to rising seas via feedbacks that build soil elevation, which lead to wetland stability. However, accelerated rates of sea-level rise can exceed soil elevation gain, leading to wetland instability and loss. Thus, there is a pressing need to better understand regional and landscape variability in rates of wetland soil elevation change. Here, we conducted a regional synthesis
Authors
Laura Feher, Michael Osland, Karen L. McKee, Kevin R.T. Whelan, Carlos A. Coronado-Molina, Fred H. Sklar, Ken Krauss, Rebecca Howard, Donald Cahoon, James C. Lynch, Lukas Lamb-Wotton, Tiffany G. Troxler, Jeremy R. Conrad, Gordon Anderson, William C. Vervaeke, Thomas J. Smith III, Nicole Cormier, Andrew From, Larry Allain

Book review: Quasispecies as a unifying concept in population dynamics

The quasispecies concept had two independent origins. One source was the theoretical ideas of Manfred Eigen and Peter Schuster in the 1970s. Studying the self-organization and evolution of primitive RNA molecules, they defined quasispecies as a distribution of mutant viral genomes generated by the mutation-selection process. In particular, the quasispecies nucleotide distribution consists of a sin
Authors
Don DeAngelis

Mapping the probability of freshwater algal blooms with various spectral indices and sources of training data

Algal blooms are pervasive in many freshwater environments and can pose risks to the health and safety of humans and other organisms. However, monitoring and tracking of potentially harmful blooms often relies on in-person observations by the public. Remote sensing has proven useful in augmenting in situ observations of algal concentration, but many hurdles hinder efficient application by end user
Authors
Tyler Victor King, Stephen Hundt, Konrad Hafen, Victoria G. Stengel, Scott D. Ducar

Bottled water contaminant exposures and potential human effects

Bottled water (BW) consumption in the United States and globally has increased amidst heightened concern about environmental contaminant exposures and health risks in drinking water supplies, despite a paucity of directly comparable, environmentally-relevant contaminant exposure data for BW. This study provides insight into exposures and cumulative risks to human health from inorganic/organic/micr
Authors
Paul M. Bradley, Kristin M. Romanok, Kelly L. Smalling, Michael J. Focazio, Nicola Evans, Suzanne C. Fitzpatrick, Carrie E Givens, Stephanie Gordon, James L. Gray, Emily M. Green, Dale W. Griffin, Michelle Hladik, Leslie K. Kanagy, John T. Lisle, Keith Loftin, R. Blaine McCleskey, Elizabeth Medlock-Kakaley, Ana Navas-Acien, David A. Roth, Paul F. South, Christopher P. Weis

Declines in reproductive condition of male largemouth bass (Micropterus salmoides) following seasonal exposure to estrogenic endocrine-disrupting compounds

Reproductive abnormalities, that could lead to possible effects at the population level, have been observed in wild fish throughout the United States, with high prevalence in largemouth bass (LMB; Micropterus salmoides) and smallmouth bass (Micropterus dolomieu). Estrone (E1) and atrazine (ATR) are common environmental contaminants often associated with agricultural land use. 17alpha-ethinylestrad
Authors
Jessica Kristin Leet, Cathy A. Richter, Robert Gale, Donald E. Tillitt, Jill Jenkins

Disentangling direct and indirect effects of extreme events on coastal wetland communities

One of the primary ways in which climate change will impact coastal freshwater wetlands is through changes in the frequency, intensity, timing and distribution of extreme weather events. Disentangling the direct and indirect mechanisms of population- and community-level responses to extreme events is vital to predicting how species composition of coastal wetlands will change under future condition
Authors
Courtney L. Davis, Susan Walls, William Barichivich, Mary Brown, David A.W. Miller