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Herman-Mercer reflects on her first article" Indigenous Observations of Change in the Lower Yukon River Basin, Alaska." The observations and knowledge presented in this study have become part of an ever-growing catalog of studies representing, and part of a chorus of Indigenous communities across the Arctic and Subarctic conveying, the...

Unusual channel-amphitheatre landforms are present in Late Pleistocene–early Holocene, subaqueous fan and delta deposits in the glacial Lake Fraser basin, central British Columbia. The lake formed during the decay of the last Cordilleran Ice Sheet and drained ~11,500 years ago during a large outburst flood. The fronts of...

Established in 1935, the Cooperative Fish and Wildlife Research Units program (CRU program) is a unique cooperative partnership among State fish and wildlife agencies, universities, the Wildlife Management Institute, the U.S. Geological Survey (USGS), and the U.S. Fish and Wildlife Service. Designed to meet the scientific needs of natural resource...

The U.S. Geological Survey (USGS) serves as the research arm of the U.S. Department of the Interior and has established a series of strategic goals that focus its efforts on serving the American people. Within the USGS, the Ecosystems Mission Area is responsible for conducting and sponsoring research that addresses...

As an unbiased, multidisciplinary science organization, the U.S. Geological Survey (USGS) is dedicated to the timely, relevant, and impartial study of the health of our ecosystems and environment, our natural resources, the impacts of climate and land-use change, and the natural hazards that affect our lives. Opportunities for undergraduate and...

Structured decision making is a systematic, transparent process for improving the quality of complex decisions by identifying measurable management objectives and feasible management actions; predicting the potential consequences of management actions relative to the stated objectives; and selecting a course of action that maximizes the total benefit achieved and balances...

Executive Summary  A previous report by the authors described sediment sampling and drilling by the U.S. Geological Survey (USGS) beside the American and Sacramento Rivers near Sacramento, California, in support of a U.S. Army Corps of Engineers project focused on regional flood control. The drilling was performed to define lithology,...

Endangered leatherback sea turtles (Dermochelys coriacea) are wide-ranging, long-distance migrants whose movements are often associated with environmental cues. We examined the spatial distribution and habitat use for 33 satellite-tracked leatherbacks from nesting beaches on the Caribbean coast of Costa Rica and Panama from 2004 to 2018,...

The U.S. Geological Survey (USGS) archive of Earth images acquired by Landsat 1-8 sensors is organized in collections of consistently calibrated, geolocated, and processed data products. Such an organization ensures consistent quality of the archived data within a collection over time and across all instruments within the Landsat mission. In...

Modeling studies project that in the future surface waters in the northeast US will continue to recover from acidification over decades following reductions in atmospheric sulfur dioxide and nitrogen oxides emissions. However, these studies generally assume stationary climatic conditions over the simulation period and ignore the linkages between soil...

By merging our specialization silos, fisheries professionals can expand the options that are available to them to address difficult fisheries and aquatic conservation problems, which require an understanding of spatial patterns in geographically large systems. Our purpose is to start a profession-wide conversation about additional ways...

Marine phosphorites are an important part of the oceanic phosphorus cycle and are related to the effects of long-term global climate changes. We use petrography, mineralogy, rare earth elements contents, and 87Sr/86Sr-determined carbonate fluorapatite (CFA) and calcite ages to investigate the paragenesis and history of phosphatization of...

Bioaerosols, including bacteria and fungi, are ubiquitous and have been shown to impact various organisms as well as biogeochemical cycles and human health. However, sample collection poses a challenge for aeromicrobiologists and can determine the success of a study. Establishing a standard collection procedure for bioaerosol...

The USGS National Wildlife Health Center (NWHC) Quarterly Mortality Report provides brief summaries of epizootic mortality and morbidity events by quarter. The write-ups, highlighting epizootic events and other wildlife disease topics of interest, are published in the Wildlife Disease Association quarterly newsletter. A link is provided in this WDA newsletter...

American black bears (Ursus americanus) are an iconic wildlife species in the southern Appalachian highlands of the eastern United States and have increased in number and range since the early 1980s. Given an increasing number of human-bear conflicts in the region, many management agencies have liberalized harvest...

Evolving complex mixtures of pharmaceuticals and transformation products in effluent-dominated streams pose potential impacts to aquatic species; thus, understanding the attenuation dynamics in the field and characterizing the prominent attenuation mechanisms of pharmaceuticals and their transformation products (TPs) is critical for hazard assessments. Herein, we...

AimWe developed a new technique, utilizing species-specific counts of individuals from historical fish community samples, to examine landscape-level, spatio-temporal trends in relative abundance distributions. Abundance-based historical distribution analyses are often plagued by data comparability issues, but provide critical information about community composition trends inaccessible to those using...

Executive SummaryThis report addresses system characterization of Planet’s Dove-R and is part of a series of system characterization reports produced and delivered by the U.S. Geological Survey Earth Resources Observation and Science Cal/Val Center of Excellence. These reports present and detail the methodology and procedures for characterization; present technical and...

Conservation practitioners increasingly recognize the conservation value of tributaries for supporting mainstem, large-river specialist fishes. A tributarys discharge at its mouth is a coarse indicator of large-river specialist fishes found within the tributary, but the relative influences of regional dispersal and local habitat underpinning this species-discharge relationship is often unknown....

Organic matter (OM) accumulation in marsh soils affects marsh survival under rapid sea-level rise (SLR). This work describes the changing organic geochemistry of a salt marsh located in the Blackwater National Wildlife Refuge on the eastern shore of Chesapeake Bay that has transgressed inland with SLR over the past 35–75 years. Marsh soils and vegetation were...

Run timing and spatial locations of spawning habitats are often used to identify stocks for conservation planning or management of salmonid fishes. Although complex stock structure is most common within large watersheds with diverse habitats, even small drainages can produce multiple co-occurring spatially or temporally isolated populations or “stocks.” This...

Global food and water insecurity could be serious problems in the upcoming decades with growing demands from the increasing global population and more frequent effect of climatic extremes. As the available water resources are diminishing and facing continuous stress, it is crucial to monitor water demand and water availability to...

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...

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...

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...