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Browse more than 65,000 articles authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Fish beta diversity associated with hydrologic and anthropogenic disturbance gradients in contrasting stream flow regimes Fish beta diversity associated with hydrologic and anthropogenic disturbance gradients in contrasting stream flow regimes
Understanding the role of hydrologic variation in structuring aquatic communities is crucial for successful conservation and sustainable management of native freshwater biodiversity. Partitioning beta diversity into the additive components of spatial turnover and nestedness can provide insight into the forces driving variability in fish assemblages across stream flow regimes. We examined...
Authors
John Tyler Fox, Cyndy Loftin
Evaluation of extinction risk for stream fishes within an urban riverscape using population viability analysis Evaluation of extinction risk for stream fishes within an urban riverscape using population viability analysis
1. The Santa Ana River in the Los Angeles region of California demonstrates common habitat degradation symptoms that are characteristic of the urban stream syndrome. These impacts have altered the Santa Ana River community structure, with few species as impacted as the native Santa Ana sucker (sucker; Pantosteus santaanae). 2. Consequently, a recovery plan developed for sucker identified...
Authors
Brock Huntsman, Kai Palenscar, Kerwin Russell, Brett Mills, Chris Jones, William Ota, Kurt E. Anderson, Heather Dyer, Fitsum Abadi, Marissa L. Wulff
Signatures of wave erosion in Titan’s coasts Signatures of wave erosion in Titan’s coasts
The shorelines of Titan’s hydrocarbon seas trace flooded erosional landforms such as river valleys; however, it is unclear whether coastal erosion has subsequently altered these shorelines. Spacecraft observations and theoretical models suggest that wind may cause waves to form on Titan’s seas, potentially driving coastal erosion, but the observational evidence of waves is indirect, and...
Authors
Rose Elizabeth Palermo, Andrew D. Ashton, Jason M. Soderblom, Samuel P. D. Birch, Alexander G. Hayes, J. Taylor Perron
Microbial communities in standing dead trees in ghost forests are largely aerobic, saprophytic, and methanotrophic Microbial communities in standing dead trees in ghost forests are largely aerobic, saprophytic, and methanotrophic
Standing dead trees (snags) are recognized for their influence on methane (CH4) cycling in coastal wetlands, yet the biogeochemical processes that control the magnitude and direction of fluxes across the snag-atmosphere interface are not fully elucidated. Herein, we analyzed microbial communities and fluxes at one height from ten snags in a ghost forest wetland. Snag-atmosphere CH4...
Authors
Mary Jane Carmichael, Melinda Martinez, Suzanna L. Bräuer, Marcelo Ardón
Bioconcentration of per- and polyfluoroalkyl substances and precursors in fathead minnow tissues environmentally exposed to aqueous film-forming foam-contaminated waters Bioconcentration of per- and polyfluoroalkyl substances and precursors in fathead minnow tissues environmentally exposed to aqueous film-forming foam-contaminated waters
Exposure to per- and polyfluoroalkyl substances (PFAS) has been associated with toxicity in wildlife and negative health effects in humans. Decades of fire training activity at Joint Base Cape Cod (MA, USA) incorporated the use of aqueous film-forming foam (AFFF), which resulted in long-term PFAS contamination of sediments, groundwater, and hydrologically connected surface waters. To...
Authors
Nicholas I. Hill, Jitka Becanova, Simon Vojta, Larry B. Barber, Denis R. LeBlanc, Alan M. Vajda, Heidi M. Pickard, Rainer Lohmann
River channel response to the removal of the Pilchuck River Diversion Dam, Washington State River channel response to the removal of the Pilchuck River Diversion Dam, Washington State
In August 2020, the 3-m tall Pilchuck River Diversion Dam was removed from the Pilchuck River, allowing free fish passage to the upper third of the watershed for the first time in over a century. The narrow, 300-m long impoundment behind the dam was estimated to hold 4,000–7,500 m3 of sand and gravel, representing less than one year's typical bedload flux. Repeat cross section surveys...
Authors
Scott W. Anderson, Brett Shattuck, Neil Shea, Catherine M. Seguin, Joe J. Miles, Derek Marks, Natasha Coumou
Documenting historical anchorworm parasitism of introduced warmwater fishes in the Willamette River Basin, Oregon Documenting historical anchorworm parasitism of introduced warmwater fishes in the Willamette River Basin, Oregon
Anchorworms (Lernaea spp.) are freshwater parasitic copepods that use a wide range of hosts. Yet little is known about their prevalence, distribution, and which species are their primary fish hosts in the state of Oregon. Institutional fish collections serve as banks which allow investigators to look at historical fish specimens and ascertain their health status at the time of their...
Authors
Elena Eberhardt, Christina Amy Murphy, William J. Gerth, Peter Konstantinidis, Ivan Arismendi
Fish size structure analysis via ordination: A visualization aid Fish size structure analysis via ordination: A visualization aid
Objective Visual aids like length-frequency histograms are widely used to examine fish population status and trends; however, comparing multiple histograms simultaneously becomes cumbersome and inefficient. Complicating matters further, overlaying covariates on histograms to highlight connections with length frequencies can be challenging. An alternative, and the subject of this...
Authors
Leandro E. Miranda
Demographics of a previously undocumented diamondback terrapin (Malaclemys terrapin) population Demographics of a previously undocumented diamondback terrapin (Malaclemys terrapin) population
Coastal habitats are some of the most imperiled due to climate change and anthropogenic activities. As such, it is important to understand population dynamics of the species that may play a role in regulating coastal systems. Diamondback terrapins in Northwest Florida have been understudied, which has resulted in a gap in our knowledge for this region. To help fill this gap, we conducted...
Authors
Daniel J. Catizone, Travis M. Thomas, Christina Romagosa, Margaret Lamont
Earthquake effects surveyed during the nineteenth century as ecological features of Chinookan tidelands Earthquake effects surveyed during the nineteenth century as ecological features of Chinookan tidelands
Lasting effects of a Cascadia earthquake in 1700 were documented during surveys of Chinookan tidelands near the mouth of the Columbia River between 1805 and 1868. The effects resemble estuarine consequences, near Anchorage, of the 1964 Alaska earthquake: fatal drowning of subsided meadows and forests by post-earthquake tides, rebirth of marshes and forests through post-earthquake...
Authors
Brian F. Atwater, David K. Yamaguchi, Jessie K. Pearl
Turbidite correlation for paleoseismology Turbidite correlation for paleoseismology
Marine turbidite paleoseismology relies on the assumption of synchronous triggering of turbidity currents by earthquake shaking to infer rupture extent and recurrence. Such inference commonly depends on age dating and correlation of the physical stratigraphy of deposits carried by turbidity currents (i.e., turbidites) across great distances. Along the Cascadia subduction zone, which lies...
Authors
Nora M. Nieminski, Zoltan Sylvester, Jake Covault, Joan S. Gomberg, Lydia M. Staisch, Ian McBrearty
Spatial patterns as long transients in submersed-floating plant competition with biocontrol Spatial patterns as long transients in submersed-floating plant competition with biocontrol
A cellular automata model was developed and parameterized to test the effectiveness of application of biological control insects to water hyacinth (Pontederia crassipes), which is an invasive floating plant species in many parts of the world and outcompetes many submersed native aquatic species in southern Florida. In the model, P. crassipes was allowed to compete with Nuttall’s...
Authors
Linhao Xu, Don DeAngelis