Articles
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
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.
Filter Total Items: 77863
Integrating telemetry data at several scales with spatial capture–recapture to improve density estimates Integrating telemetry data at several scales with spatial capture–recapture to improve density estimates
Accurate population estimates are essential for monitoring and managing wildlife populations. Mark–recapture sampling methods have regularly been used to estimate population parameters for rare and cryptic species, including the federally listed Mojave desert tortoise (Gopherus agassizii); however, the methods employed are often plagued by violations of statistical assumptions, which...
Authors
Corey I Mitchell, Kevin T. Shoemaker, Todd Esque, Amy G. Vandergast, Steven J. Hromada, Kirsten E. Dutcher, Jill S. Heaton, Kenneth E. Nussear
Holocene hydroclimatic reorganizations in northwest Canada inferred from lacustrine carbonate oxygen isotopes Holocene hydroclimatic reorganizations in northwest Canada inferred from lacustrine carbonate oxygen isotopes
Sub-centennial oxygen (δ18O) isotopes of ostracod and authigenic calcite from Squanga Lake provides evidence of hydroclimatic extremes and a series of post-glacial climate system reorganizations for the interior region of northwest Canada. Authigenic calcite δ18O values range from −16‰ to −21‰ and are presently similar to modern lake water and annual precipitation values. Ostracod δ18O...
Authors
G. Everett Lasher, Mark B. Abbott, Lesleigh Anderson, Lindsey Yasarer, Michael Rosenheimer, Bruce P. Finney
Corticosterone mediates a growth-survival tradeoff for an amphibian exposed to increased salinity Corticosterone mediates a growth-survival tradeoff for an amphibian exposed to increased salinity
Life-history tradeoffs are common across taxa, but growth-survival tradeoffs—usually enhancing survival at a cost to growth—are less frequently investigated. Increased salinity (NaCl) is a prevalent anthropogenic disturbance that may cause a growth-survival tradeoff for larval amphibians. Although physiological mechanisms mediating tradeoffs are seldom investigated, hormones are prime...
Authors
BJ Tornabene, Blake R. Hossack, EJ Crespi, CW Breuner
Hawai‘i forest review: Synthesizing the ecology, evolution, and conservation of a model system Hawai‘i forest review: Synthesizing the ecology, evolution, and conservation of a model system
As the most remote archipelago in the world, the Hawaiian Islands are home to a highly endemic and disharmonic biota that has fascinated biologists for centuries. Forests are the dominant terrestrial biome in Hawai‘i, spanning complex, heterogeneous climates across substrates that vary tremendously in age, soil structure, and nutrient availability. Species richness is low in Hawaiian...
Authors
Kasey Barton, Andrea Westerband, Rebecca Ostertag, Elizabeth Stacy, Kawika Winter, Don Drake, Lucas Berio Fortini, Creighton M Litton, Susan Cordell, Paul Krushelnycky, Kapua Kawelo, Kealoha Feliciano, Gordon Bennett, Tiffany Knight
Improving evaluation of nonlethal tools for carnivore management and conservation: Evaluating fladry to protect an endangered species from a generalist mesocarnivore Improving evaluation of nonlethal tools for carnivore management and conservation: Evaluating fladry to protect an endangered species from a generalist mesocarnivore
Carnivore conservation and management are global research priorities focused on reversing population declines of imperiled species and identifying more effective and humane management of generalist carnivores with thriving populations. Nonlethal methods to mitigate conflict are increasingly used to advance conservation objectives; however, there is limited knowledge about the...
Authors
Rebecca Windell, Larissa L. Bailey, Julie K. Young, Travis M. Livieri, David A. Eads, Stewart Breck
Evaluating the migration mortality hypothesis using monarch tagging data Evaluating the migration mortality hypothesis using monarch tagging data
The decline in the eastern North American population of the monarch butterfly population since the late 1990s has been attributed to the loss of milkweed during the summer breeding season and the consequent reduction in the size of the summer population that migrates to central Mexico to overwinter (milkweed limitation hypothesis). However, in some studies the size of the summer...
Authors
Orley R. Taylor, John M. Pleasants, Ralph Grundel, Samuel Pecoraro, James P. Lovett, Ann Ryan
Diet composition of Fishers (Pekania pennanti) reintroduced on the Olympic Peninsula, Washington Diet composition of Fishers (Pekania pennanti) reintroduced on the Olympic Peninsula, Washington
Knowledge of diet composition can inform management strategies and efforts to recover endangered carnivore populations in vacant portions of their historic ranges. One such species, the Fisher (Pekania pennanti), was extirpated in Washington State prior to any formal documentation of its food habits in the coastal coniferous forests of western Washington. Fisher recovery efforts in...
Authors
Patricia J. Happe, Shelby H. Pace, Laura R. Prugh, Kurt Jenkins, Jeffrey C. Lewis, Joan Hagar
Brown treesnake mortality after aerial application of toxic baits Brown treesnake mortality after aerial application of toxic baits
Quantitative evaluation of control tools for managing invasive species is necessary to assess overall effectiveness and individual variation in treatment susceptibility. Invasive brown treesnakes (Boiga irregularis) on Guam have caused severe ecological and economic effects, pose a risk of accidental introduction to other islands, and are the greatest impediment to the reestablishment of
Authors
Scott Michael Goetz, Eric T. Hileman, Melia G. Nafus, Amy A. Yackel Adams, Amanda R Bryant, Robert Reed, Shane R. Siers
Integrating ecosystem metabolism and consumer allochthony reveals nonlinear drivers in lake organic matter processing Integrating ecosystem metabolism and consumer allochthony reveals nonlinear drivers in lake organic matter processing
Lakes process both terrestrial and aquatic organic matter, and the relative contribution from each source is often measured via ecosystem metabolism and terrestrial resource use in the food web (i.e., consumer allochthony). Yet, ecosystem metabolism and consumer allochthony are rarely considered together, despite possible interactions and potential for them to respond to the same lake
Authors
Meredith A. Holgerson, Rachel A. Hovel, Patrick T. Kelly, Lauren E Bortolotti, Jennifer A. Brentrup, Amber R Bellamy, Samantha K. Oliver, Alexander J Reisenger
Quaternary reelfoot fault deformation in the Obion River Valley, Tennessee, USA Quaternary reelfoot fault deformation in the Obion River Valley, Tennessee, USA
Blind reverse faults are challenging to detect, and earthquake records can be elusive because deep fault slip does not break the surface along readily recognized scarps. The blind Reelfoot fault in the New Madrid seismic zone in the central United States has been the subject of extensive prior investigation; however, the extent of slip at the southern portion of the fault remains...
Authors
Jaime Delano, Richard W. Briggs, Jessica Ann Thompson Jobe, Ryan D. Gold, Simon E. Engelhart
A review of the phyllosilicates in Gale Crater as detected by the CheMin Instrument on the Mars Science Laboratory, Curiosity Rover A review of the phyllosilicates in Gale Crater as detected by the CheMin Instrument on the Mars Science Laboratory, Curiosity Rover
Curiosity, the Mars Science Laboratory (MSL) rover, landed on Mars in August 2012 to investigate the ~3.5-billion-year-old (Ga) fluvio-lacustrine sedimentary deposits of Aeolis Mons (informally known as Mount Sharp) and the surrounding plains (Aeolis Palus) in Gale crater. After nearly nine years, Curiosity has traversed over 25 km, and the Chemistry and Mineralogy (CheMin) X-ray...
Authors
Valerie M. Tu, Elizabeth B. Rampe, Thomas F. Bristow, Michael T. Thorpe, Joanna V. Clark, Nicholas Castle, Abigail A. Fraeman, Lauren A. Edgar, Amy McAdam, Candice C. Bedford, Cherie N. Achilles, David Blake, Steve J. Chipera, Patricia I. Craig, David J. Des Marais, Gordie W. Downs, Robert T. Downs, Valerie K. Fox, John P. Grotzinger, Robert M. Hazen, Douglas W. Ming, Richard V. Morris, Shaunna M. Morrison, Betina Pavri, Tanya S. Peretyazhko, Philippe C. Sarazin, Brad Sutter, Allan H. Treiman, David T. Vaniman, Albert S. Yen, Jon C. Bridges
Distributions of native and invasive Typha (cattail) throughout the Prairie Pothole Region of North America Distributions of native and invasive Typha (cattail) throughout the Prairie Pothole Region of North America
The Prairie Pothole Region (PPR) of North America has experienced extreme changes in wetland habitat due to proliferation of invasive plants. Typha × glauca is a highly competitive hybrid between native T. latifolia and non-native T. angustifolia, and it is likely the predominant taxon in PPR wetlands. Genetics-based studies are limited, and distributions are poorly known for the first...
Authors
Brian Tangen, Sheel Bansal, Joanna R. Freeland, Steven E. Travis, Jen D. Wasko, Terence P. McGonigle, L. Gordon Goldsborough, Keira Gow, Joy E. Marburger, Jacob Meier