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A National Program to Assess Hazards, Risk, and Resiliency

In 2007, the U.S. Geological Survey (USGS) developed a science strategy outlining the major natural science issues facing the Nation in the next decade. The science strategy consists of six science directions of critical importance, focusing on areas where natural science can make a substantial contribution to the well-being of the Nation and the world. This fact sheet focuses on a program to assess natural hazards and how USGS research can strengthen the Nation with information needed to meet the challenges of the 21st century.

Fact Sheet

Facing Tomorrow's Challenges - An Overview

In 2007, the U.S. Geological Survey (USGS) developed a science strategy outlining the major natural-science issues facing the Nation in the next decade. The science strategy consists of six science directions of critical importance, focusing on areas where natural science can make a substantial contribution to the well-being of the Nation and the world. This fact sheet is an overview of the science strategy and describes how USGS research can strengthen the Nation with information needed to meet the challenges of the 21st century.

Fact Sheet

Hydrologic and landscape database for the Cache and White River National Wildlife Refuges and contributing watersheds in Arkansas, Missouri, and Oklahoma

A hydrologic and landscape database was developed by the U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, for the Cache River and White River National Wildlife Refuges and their contributing watersheds in Arkansas, Missouri, and Oklahoma. The database is composed of a set of ASCII files, Microsoft Access® files, Microsoft Excel® files, an Environmental Systems Research Institute (ESRI) ArcGIS® geodatabase, ESRI ArcGRID® raster datasets, and an ESRI ArcReader® published map. The database was developed as an assessment and evaluation tool to use in examining refuge-specific hydrologic patterns and trends as related to water availability for refuge ecosystems, habitats, and target species; and includes hydrologic time-series data, statistics, and hydroecological metrics that can be used to assess refuge hydrologic conditions and the availability of aquatic and riparian habitat. Landscape data that describe the refuge physiographic setting and the locations of hydrologic-data collection stations are also included in the database. Categories of landscape data include land cover, soil hydrologic characteristics, physiographic features, geographic and hydrographic boundaries, hydrographic features, regional runoff estimates, and gaging-station locations. The database geographic extent covers three hydrologic subregions—the Lower Mississippi–St Francis (0802), the Upper White (1101), and the Lower Arkansas (1111)—within which human activities, climatic variation, and hydrologic processes can potentially affect the hydrologic regime of the refuges and adjacent areas. Database construction has been automated to facilitate periodic updates with new data. The database report (1) serves as a user guide for the database, (2) describes the data-collection, data-reduction, and data-analysis methods used to construct the database, (3) provides a statistical and graphical description of the database, and (4) provides detailed information on the development of analytical techniques designed to assess water availability for ecological needs.

Arkansas;Missouri;Oklahoma

Citizen science data collection for integrated wildlife population analyses

Citizen science, or community science, has emerged as a cost-efficient method to collect data for wildlife monitoring. To inform research and conservation, citizen science sampling designs should collect data that match the robust statistical analyses needed to quantify species and population patterns. Further increasing the contributions of citizen science, integrating citizen science data with other datasets and datatypes can improve population estimates and expand the spatiotemporal extent of inference. We demonstrate these points with a citizen science program called iSeeMammals developed in New York state in 2017 to supplement costly systematic spatial capture-recapture sampling by collecting opportunistic data from one-off observations, hikes, and camera traps. iSeeMammals has initially focused on the growing population of American black bear ( Ursus americanus ), with integrated analysis of iSeeMammals camera trap data with systematic data for a region with a growing bear population. The triumvirate of increased spatial and temporal coverage by at least twofold compared to systematic sampling, an 83% reduction in annual sampling costs, and improved density estimates when integrated with systematic data highlight the benefits of collecting presence-absence data in citizen science programs for estimating population patterns. Additional opportunities will come from applying presence-only data, which are oftentimes more prevalent than presence-absence data, to integrated models. Patterns in data submission and filtering also emphasize the importance of iteratively evaluating patterns in engagement, usability, and accessibility, especially focusing on younger adult and teenage demographics, to improve data quality and quantity. We explore how the development and use of integrated models may be paired with citizen science project design in order to facilitate repeated use of datasets in standalone and integrated analyses for supporting wildlife monitoring and informing conservation.

Frontiers in Ecology and Evolution

Science-based management of public lands in southern Nevada

Landmark legislation provides guiding principles for land management planning in southern Nevada and the rest of the United States. Such legislation includes, but is not limited to, the Forest Service Organic Administration Act of 1897 (16 U.S>C. 473-478, 479-482 and 551), National Park Service Organic Act of 1916 (U.S.C. Title 16, Secs. 1-4). Wilderness Act 1964 (P.L.88-577), National Environmental Policy Act of 1969 (P.L. 91-190), Endangered Species Act of 1973 (P.L. 91-205), National Forest Management Act of of 1976 (P.L. 94-588), and Federal Land Policy and Management Act of 1976 (P.L. 94-579). The acts establishing congressionally designated areas within southern Nevada, such as Lake Mead National Recreation Area, Spring Mountains National Restoration Area, and Desert National Wildlife Refuge, also contain guidelines for the management of these lands. These documents variously require preservation of natural and cultural resource and wilderness character, protection of species, and prevention of undesirable environmental effects from land management actions. These requirements must be met while allowing for multiple "uses" of certain public lands (e.g. recreation, ranching, resources extraction, renewable energy development, etc.) to the degree that they do no threaten preservation, protection, and prevention goals,. many considerations some into play in the development and implementation for land management plans and actions. The planning process requires a balancing act that sometimes pit one need or priority against another. When priorities can trump other needs can prioritized and receive disproportionate consideration. Overall, the management of public lands is a very complicated and sometime contentious process. Science provides an objective way to help weigh quantifiable information and draw conclusions about the effects of past and potential future land management policies, decisions, and actions. When effectively integrated into adaptive management, science-based information can reduce uncertainties, increase knowledge, and improve decision making. However, the specific science information needed for effective management is often lacking or difficult to access or interpret. Science is typically reported in scientific journals as discrete units describing individual studies with other scientists as the primary audience. Translations of these studies an synthesis or multiple studies into formats that can be readily used in land management planning efforts are often lacking. Identifying and articulating the highest priority science and research needs is one of the primary purposes of the Southern Nevada Agency Partnership (SNAP; http://www.SNAP.gov) Science and Research Team (chapter 1; Turner and others 2009). The SNAP Science and Research Strategy (Strategy) calls for a synthesis report to be written every 5 years summarizing the state of knowledge, information gaps and management implications of scientific information as it relates to the SNAP Strategy goals (Turner and others 2009). This General Technical Report serves as the first SNAP Science and Research Synthesis Report (Synthesis Report) commissioned by the Science and Research Team. The Synthesis Report is mostly based on information form the peer-reviewed scientific literature, and is itself peer reviewed and constitutes a new contribution to the scientific literature. This final chapter addresses Sub-goal 2.3, which is to manage current and future authorized southern Nevada land uses in a manner that balances public need and ecosystem sustainability, and Sub-goal 2.5, which is to promote an effective conservation education and interpretation program to improve the quality of resources and enhance public use and enjoyment of southern Nevada public lands. It summarizes information form the previous chapters on what scientific information is known currently and what remains largely unknown, and it discusses how science can be used to make future management decisions that balances public needs and ecosystem sustainability.

Nevada

High-resolution geophysical data from the sea floor surrounding the Western Elizabeth Islands, Massachusetts

Geophysical and geospatial data were collected in the nearshore area surrounding the western Elizabeth Islands, Massachusetts on the U.S. Geological Survey research vessel Rafael during September 2010 in a collaborative effort between the U.S. Geological Survey and the Massachusetts, Office of Coastal Zone Management. This report describes the results of the short-term goals of this collaborative effort, which were to map the geology of the inner shelf zone of the western Elizabeth Islands and study the geologic processes that have contributed to its evolution. Data collected during the survey include: Bathymetric and sidescan-sonar data, chirp seismic-reflection data , sound velocity profiles, and navigation data. The long-term goals of this project are to provide high-resolution geophysical data that will support research on the influence of sea-level change and sediment supply on coastal evolution and inventory subtidal marine habitat type and distribution within the coastal zone of Massachusetts.

Massachusetts

Hotspot dune erosion on an intermediate beach

A large, low pressure Nor’easter storm and Hurricane Joaquin contributed to multiple weeks of sustained, elevated wave and water level conditions along the southeastern Atlantic coast of the United States in Fall 2015. Sea level anomalies in excess of 1 m and offshore wave heights of up to 4 m were recorded during these storms, as observed at the U.S. Army Corps of Engineers’ Field Research Facility in Duck, NC, USA. In response to these energetic oceanographic conditions, there were highly variable morphologic changes to the dune over short spatial scales (<km) which included a range of responses from vertical dune scarping to no measureable response. The portion of the study area with the largest dune erosion occurred at a location fronted by an abnormally deep nearshore bathymetric feature, which altered surf-zone waves and hydrodynamics. The pre-storm beach and dune topography also varied throughout the study area, additionally influencing the frequency of dune collision and contributing to the spatially variable erosion patterns. This work uses field datasets and numerical modeling tools to investigate the causation of hotspot dune erosion at the Field Research Facility. Three different numerical models were tested against the available data in order to assess model skill at resolving complex spatial dune erosion patterns. The three models successfully reproduce the general spatial trends in alongshore variable responses, although not necessarily the details of profile response or net erosion magnitude. Analysis of the model outputs, in conjunction with the available field data, suggests that the observed hotspot dune erosion is related to a complex combination of both topographic and bathymetric controls on the processes driving dune erosion. Therefore, the most simplistic model tested, which only accounts for alongshore variations in topographic profile details, can only predict hotspot dune erosion in locations where steep beach and/or dune topography is the primary control on collisional dune impacts. The higher fidelity models , which account for feedback effects from subaqueous morphology, are similarly able to predict the locations of maximum hotspot erosion, but are sensitive to beach over-steepening and/or errors in wave runup calculations that can lead to over-prediction of simulated dune erosion. This work highlights that numerous existing tools are capable of identifying the foredune regions at most risk from hotspot erosion, as well as the need for continued research to improve representation of all relevant intra-storm morphodynamic processes.

Coastal Engineering

Integrating science and resource management in Tampa Bay, Florida

Tampa Bay is recognized internationally for its remarkable progress towards recovery since it was pronounced "dead" in the late 1970s. Due to significant efforts by local governments, industries and private citizens throughout the watershed, water clarity in Tampa Bay is now equal to what it was in 1950, when population in the watershed was less than one-quarter of what it is today. Seagrass extent has increased by more than 8,000 acres since the mid-1980s, and fish and wildlife populations are increasing. Central to this successful turn-around has been the Tampa Bay resource management community's long-term commitment to development and implementation of strong science-based management strategies. Research institutions and agencies, including Eckerd College, the Florida Wildlife Commission Fish and Wildlife Research Institute, Mote Marine Laboratory, National Oceanic and Atmospheric Administration, the Southwest Florida Water Management District, University of South Florida, U.S. Environmental Protection Agency, U.S. Geological Survey, local and State governments, and private companies contribute significantly to the scientific basis of our understanding of Tampa Bay's structure and ecological function. Resource management agencies, including the Tampa Bay Regional Planning Council's Agency on Bay Management, the Southwest Florida Water Management District's Surface Water Improvement and Management Program, and the Tampa Bay Estuary Program, depend upon this scientific basis to develop and implement regional adaptive management programs. The importance of integrating science with management has become fully recognized by scientists and managers throughout the region, State and Nation. Scientific studies conducted in Tampa Bay over the past 10&ndash;15 years are increasingly diverse and complex, and resource management programs reflect our increased knowledge of geology, hydrology and hydrodynamics, ecology and restoration techniques. However, a synthesis of this research and its integration into resource management has not been prepared for Tampa Bay since the mid-1980s. The need for an up-to-date synthesis of Tampa Bay science and management has resulted in the production of this document. The U.S. Geological Survey recently completed a 5-year Tampa Bay Integrated Science Study, and the Tampa Bay Estuary Program updated the Comprehensive Conservation and Management Plan for Tampa Bay in 2006. These efforts build upon results of the many research and management studies and programs summarized here.

Florida

Incremental evolution of modeling a prognosis for polar bears in a rapidly changing Arctic

Updating predictions of the response of high-profile, at-risk species to climate change and anthropogenic stressors is vital for informing effective conservation action. Here, we review two prior generations of Bayesian network probability models predicting changes in global polar bear ( Ursus maritimus ) population status, and provide a contemporary update based on recent research findings and sea-ice projections by newer climate models. We compare predictions of polar bear population response from all 3 models among four circumpolar Arctic ecoregions, using sea ice projections based on three IPCC greenhouse gas emissions scenarios (SSP2.6, 4.5, 8.5). Consistent with the previous two model generations, polar bears will continue to experience increasing probability of declining or greatly declining populations throughout the 21st century, varying by emission scenario. Populations within the Polar Basin Divergent Ice Ecoregion have the highest predicted probability of declines, but predictions were slightly less dire relative to the previous model generation. Most of the influence, denoted by model sensitivity analysis, is from expected degradation and loss of sea ice and reduced access to marine prey. The lack of terrestrial prey adequate to substitute for loss of access to marine prey, as well as human-caused bear morality associated with hunting and defense of life and property encountered when polar bears are increasingly forced ashore also contributed to predicted declines. Although some tidewater glacial fjords and other localized onshore resources may provide local refugia, their benefit is transient. Our findings continue to inform priorities for inventory, monitoring, and research needs, and suggest that similar updates to models of other at-risk species can capitalize on the comparison framework we present here.

Ecological Indicators

Hydrologic impacts of landslide disturbances: Implications for remobilization and hazard persistence

Landslides typically alter hillslope topography, but may also change the hydrologic connectivity and subsurface water-storage dynamics. In settings where mobile materials are not completely evacuated from steep slopes, influences of landslide disturbances on hillslope hydrology and susceptibility to subsequent failures remain poorly characterized. Since landslides often recur at the site of previous failures, we examine differences between a stable vegetated hillslope (VH) and a recent landslide (LS). These neighboring hillslopes exhibit similar topography and are situated on steep landslide-prone coastal bluffs of glacial deposits along the northeastern shore of Puget Sound, Washington. Our control hillslope, VH, is mantled by a heterogeneous colluvium, supporting a dense forest. In early 2013, our test hillslope, LS, also supported a forest before a landslide substantially altered the topography and disturbed the hillslope. In 2015, we observed a clay-rich landslide deposit at LS with sparse vegetation and limited root reinforcement, soil structures, and macropores. Our characterization of the sites also found matrix porosity and hydraulic conductivity are both lower at LS. Continuous monitoring during 2015-2016 revealed reduced effective precipitation at VH (due to canopy interception), an earlier seasonal transition to near-saturated conditions at LS, and longer persistence of positive pore pressures and slower drainage at LS (both seasonally and between major storm events). These differences, along with episodic, complex slope failures at LS support the hypothesis that, despite a reduced average slope, other disturbances introduced by landsliding may promote the hydrologic conditions leading to slope instability, thus contributing to the persistence of landslide hazards.

Washington

Does where they start affect where they finish? A multimethod investigation of the role of stocking location on survival and dispersal of hatchery-reared Lake Sturgeon in Missouri River tributaries

Despite ongoing Lake Sturgeon recovery efforts, little is known about the role of stocking location on survival and dispersal to nursery habitats. We stocked age-0 Lake Sturgeon at four sites in two adjacent Missouri River tributaries and used telemetry to examine whether survival and dispersal differed among stocking sites and rivers. Survival estimates from Barker Cormack-Jolly-Seber models that incorporated both receiver detections and auxiliary manual detections were higher than spatial capture-recapture models that only included receiver detections. Barker model overwinter survival averaged 53% and provided information to adjust individual censoring in spatial capture-recapture model dispersal estimates. Within the two rivers, stocking site had little effect on activity centers with individuals from both sites converging upon similar locations by the end of the study period. However, dispersal distance and direction differed among stocking locations. Our overwinter survival estimates of stocked age-0 Lake Sturgeon in Missouri River tributaries were equal to or higher than other studied populations suggesting stocked juveniles may be contributing to the recovering population. Tributaries were important overwintering nursery locations with high stream fidelity that may contribute to future homing among adults.

Missouri

Shallow subsurface storm flow in a forested headwater catchment: Observations and modeling using a modified TOPMODEL

Transient, perched water tables in the shallow subsurface are observed at the South Fork Brokenback Run catchment in Shenandoah National Park, Virginia. Crest piezometers installed along a hillslope transect show that the development of saturated conditions in the upper 1.5 m of the subsurface is controlled by total precipitation and antecedent conditions, not precipitation intensity, although soil heterogeneities strongly influence local response. The macroporous subsurface storm flow zone provides a hydrological pathway for rapid runoff generation apart from the underlying groundwater zone, a conceptualization supported by the two‐storage system exhibited by hydrograph recession analysis. A modified version of TOPMODEL is used to simulate the observed catchment dynamics. In this model, generalized topographic index theory is applied to the subsurface storm flow zone to account for logarithmic storm flow recessions, indicative of linearly decreasing transmissivity with depth. Vertical drainage to the groundwater zone is required, and both subsurface reservoirs are considered to contribute to surface saturation.

Water Resources Research

Mount St. Helens Petrology Workshop

Following seismic activity in late September 2004, the current eruption of Mount St. Helens began with an explosive steam and ash emission on 1 October 2004, with hot dacite emerging from the crater floor on 11 October 2004. Nearly two years later, with more than 80 million cubic meters of erupted dacite, accompanied by rare explosions and predominantly shallow seismicity questions still remain about what initiated and what is sustaining the eruption. The U.S. Geological Survey's (USGS) Cascade Volcano Observatory (CVO) hosted the 2006 Mount St. Helens Petrology Workshop in Vancouver, Wash., on 27–30 August 2006. With many of the more than 40 workshop participants finalizing contributions to a USGS Professional Paper on the current Mount St. Helens eruption, the workshop was a timely opportunity to share results, reconcile interpretations, and plan future research.

Washington

Geochemical evidence for diachronous uplift and synchronous collapse of the high elevation Variscan hinterland

Competing end-member models for the late Paleozoic Variscan orogeny (ca. 360-290 Ma) alternatively suggest moderate 2-3 km elevations underlain by relatively thin crust (<50 km) or a thick crust (>55 km) that supported high 4-5 km elevations. We tested these models and quantified the crustal thickness and elevation evolution of the Variscan orogeny using igneous trace element geochemical proxies. The data suggest that thick crust (55-70 km) capable of supporting 3-5 km elevations developed diachronously from east to west between ca. 350 and 315 Ma. Crustal thinning occurred from ca. 315 Ma to 290 Ma across the orogen. Crustal thickness and elevation changes at ca. 340-325 Ma and 315-290 Ma correspond with increases in silicate weathering recorded by Sr and Li isotopes, consistent with models in which silicate weathering of the Variscan orogen contributed to global cooling associated with the late Paleozoic ice age.

Black Forest

Ambiguities in using telomere length for age determination in two North American bat species

The age of an animal, determined by time (chronological age) as well as genetic and environmental factors (biological age), influences the likelihood of mortality and reproduction and thus the animal’s contribution to population growth. For many long-lived species, such as bats, a lack of external and morphological indicators has made determining age a challenge, leading researchers to examine genetic markers of age for application to demographic studies. One widely studied biomarker of age is telomere length, which has been related both to chronological and biological age across taxa, but only recently has begun to be studied in bats. We assessed telomere length from the DNA of known-age and minimum known-age individuals of two bat species using a quantitative PCR assay. We determined that telomere length was quadratically related to chronological age in big brown bats ( Eptesicus fuscus ), although it had little predictive power for accurate age determination of unknown-age individuals. The relationship was different in little brown bats ( Myotis lucifugus ), where telomere length instead was correlated with biological age, apparently due to infection and wing damage associated with white-nose syndrome. Furthermore, we showed that wing biopsies currently are a better tissue source for studying telomere length in bats than guano and buccal swabs; the results from the latter group were more variable and potentially influenced by storage time. Refinement of collection and assessment methods for different non-lethally collected tissues will be important for longitudinal sampling to better understand telomere dynamics in these long-lived species. Although further work is needed to develop a biomarker capable of determining chronological age in bats, our results suggest that biological age, as reflected in telomere length, may be influenced by extrinsic stressors such as disease.

Journal of Mammalogy

Chloride inhibition of nitrite-induced methemoglobinemia in channel catfish (Ictalurus punctatus)

Exposure of channel catfish (Ictalurus punctatus) fingerlings for 24?h to 1.0, 2.5, and 5.0?mg/L nitrite (pH?=?7; hardness?=?40?mg/L; temperature?=?22&ndash;25 &deg;C) produced methemoglobin levels of 20.7?&plusmn;?1.9%, 59.8?&plusmn;?1.9%, and 77.4?&plusmn;?1.4% (SE), respectively. However, methemoglobin levels were not elevated when fish were simultaneously exposed to 1.0, 2.5, and 5.0?mg/L nitrite and 25, 50, and 100?mg/L sodium chloride, respectively. Acclimation to sodium chloride for 24?h before exposure to nitrite did not enhance the inhibitory action of sodium chloride. Fish exposed to 5?mg/L nitrite for 5?h developed 42.5?&plusmn;?3.8% methemoglobin. When transferred to water containing 5?mg/L nitrite and 250?mg/L sodium chloride, methemoglobin levels returned to normal within 24?h. Environmental chloride probably inhibits methemoglobin formation by competing with nitrite for entrance into the gills of the fish. An ionic ratio of 16 Cl - to 1 NO 2 - is capable of complete suppression of nitrite-induced methemoglobin formation. Bicarbonate ion present in the test water (1?meq/L) may also have contributed to the inhibitive action of chloride.

Journal of the Fisheries Research Board of Canada

Smaller body size under warming is not due to gill-oxygen limitation in a coldwater salmonid

Declining body size in fishes and other aquatic ectotherms associated with anthropogenic climate warming has significant implications for future fisheries yields, stock assessments and aquatic ecosystem stability. One proposed mechanism seeking to explain such body-size reductions, known as the gill oxygen limitation (GOL) hypothesis, has recently been used to model future impacts of climate warming on fisheries but has not been robustly empirically tested. We used brook trout ( Salvelinus fontinalis ), a fast-growing, cold-water salmonid species of broad economic, conservation and ecological value, to examine the GOL hypothesis in a long-term experiment quantifying effects of temperature on growth, resting metabolic rate (RMR), maximum metabolic rate (MMR) and gill surface area (GSA). Despite significantly reduced growth and body size at an elevated temperature, allometric slopes of GSA were not significantly different than 1.0 and were above those for RMR and MMR at both temperature treatments (15°C and 20°C), contrary to GOL expectations. We also found that the effect of temperature on RMR was time-dependent, contradicting the prediction that heightened temperatures increase metabolic rates and reinforcing the importance of longer-term exposures (e.g. >6 months) to fully understand the influence of acclimation on temperature–metabolic rate relationships. Our results indicate that although oxygen limitation may be important in some aspects of temperature–body size relationships and constraints on metabolic supply may contribute to reduced growth in some cases, it is unlikely that GOL is a universal mechanism explaining temperature–body size relationships in aquatic ectotherms. We suggest future research focus on alternative mechanisms underlying temperature–body size relationships, and that projections of climate change impacts on fisheries yields using models based on GOL assumptions be interpreted with caution.

Journal of Experimental Biology

Sediment load from major rivers into Puget Sound and its adjacent waters

Each year, an estimated load of 6.5 million tons of sediment is transported by rivers to Puget Sound and its adjacent waters&mdash;enough to cover a football field to the height of six Space Needles. This estimated load is highly uncertain because sediment studies and available sediment-load data are sparse and historically limited to specific rivers, short time frames, and a narrow range of hydrologic conditions. The largest sediment loads are carried by rivers with glaciated volcanoes in their headwaters. Research suggests 70 percent of the sediment load delivered to Puget Sound is from rivers and 30 percent is from shoreline erosion, but the magnitude of specific contributions is highly uncertain. Most of a river's sediment load occurs during floods.

Washington