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At least 991 records · Page 55Linked to original sources
USGS1994

Identification of potential public water-supply areas of the Cape Cod aquifer, Massachusetts, using a geographic information system

Potential public water-supply areas of the Cape Cod aquifer, Massachusetts, were identified using a geographic information system (GIS) to aid regional and local ground-water resource management efforts. Criteria were selected to identify potential areas on the basis of data restrictions in addition to State requirements for siting new public water- supply wells, Federal or local restrictions on land use, and general hydrogeologic or water-quality concerns. Data layers were created for each criterion and overliad to eliminate areas from consideration as potential public water supplies. Remaining areas, those not included within the applied criteria, are the primary areas to consider for potential public water supplies. The areas identified in this analysis as potential public water supplies range from 0.5 to 7.9 percent of the individual flow cells, or 5.6 percent of the total flow cell area. The criteria were ranked so that criteria more limiting to potential public water supplies were given a higher rank than other criteria. The ranking scheme allows for the inclusion of areas with lower ranked criteria as potential public water supplies. Results can be viewed on a plat in this report, or accessed using the map-based, menu-driven GIS application, which provides interactive display and query of investigation results.

Water-Resources Investigations Report↗
USGS2023

Habitat utilization, demography, and behavioral observations of the squat lobster, Eumunida picta (Crustacea: Anomura: Eumunididae), on western North Atlantic deep-water coral habitats

Deep-sea coral habitats, comprising mostly Lophelia pertusa (Linnaeus 1758), are well developed on the upper and middle continental slope off the southeastern United States (SEUS). These habitats support a diverse and abundant invertebrate fauna, yet ecology and biology of most of these species are poorly known. Ten cruises conducted off the SEUS (Summer–Fall; Cape Lookout, NC–Cape Canaveral, FL) from 2000 to 2005, and in 2009 provided an opportunity to investigate abundance and distribution of Eumunida picta Smith1883, a large-sized species of squat lobster commonly associated with these deep-water coral habitats. Video analysis from 70 manned-submersible dives documented occurrence, density, location on the coral colony, and behavioral observations for 5774 individuals of E . picta . Individuals collected (n = 178) from coral and adjacent habitats (e.g., rubble, soft sediments) were measured and their sex determined. Males and females were comparable in size (to 53.5 mm carapace length) and exhibited a sex ratio of approximately 1:1. Eumunida picta were most frequently observed as solitary individuals on high-profile coral matrix and were noted only infrequently on coral rubble, or rarely on soft substratum. Presence of coral habitat (i.e., live/dead L. pertusa ), geographic region within the sampling area, and depth significantly influenced abundances of E. picta . Additionally, coral habitat (dead versus live coral), vertical position on the coral (upper, middle, or lower zone), as well as horizontal position in relation to the coral matrix (outer surface versus embedded in coral matrix) were significant factors influencing E. picta distributions within the coral habitat. More individuals were found on dead versus live coral, and most frequently occurred on the outer surfaces of coral branches located on the upper portion or near the tops of coral colonies. Eumunida picta were most often observed with claws extended into the water column. This unique hunting stance provides this squat lobster the opportunity to capture prey from the water column. An active predator, this species utilizes both pelagic (i.e., fishes, pyrosomes) and benthic (e.g., scavenging and grazing) food resources, and may function as an important trophic link between the water column and the benthos. Although considered a facultative reef associate in the strictest sense of the term, E. picta has a complex and intimate relationship with L. pertusa . Based on observations from dive videos, E. picta is a dominant and ecologically important member of the invertebrate assemblage associated with deep-sea coral habitats off the SEUS. As such, this species figures prominently in the structure and function of this ecosystem.

western North Atlantic↗
USGS2012

Ontogenetic and among-individual variation in foraging strategies of northeast Pacific white sharks based on stable isotope analysis

There is growing evidence for individuality in dietary preferences and foraging behaviors within populations of various species. This is especially important for apex predators, since they can potentially have wide dietary niches and a large impact on trophic dynamics within ecosystems. We evaluate the diet of an apex predator, the white shark ( Carcharodon carcharias ), by measuring the stable carbon and nitrogen isotope composition of vertebral growth bands to create lifetime records for 15 individuals from California. Isotopic variations in white shark diets can reflect within-region differences among prey (most importantly related to trophic level), as well as differences in baseline values among the regions in which sharks forage, and both prey and habitat preferences may shift with age. The magnitude of isotopic variation among sharks in our study (>5‰ for both elements) is too great to be explained solely by geographic differences, and so must reflect differences in prey choice that may vary with sex, size, age and location. Ontogenetic patterns in δ 15 N values vary considerably among individuals, and one third of the population fit each of these descriptions: 1) δ 15 N values increased throughout life, 2) δ 15 N values increased to a plateau at ~5 years of age, and 3) δ 15 N values remained roughly constant values throughout life. Isotopic data for the population span more than one trophic level, and we offer a qualitative evaluation of diet using shark-specific collagen discrimination factors estimated from a 3+ year captive feeding experiment (Δ 13 C shark-diet and Δ 15 N shark-diet equal 4.2‰ and 2.5‰, respectively). We assess the degree of individuality with a proportional similarity index that distinguishes specialists and generalists. The isotopic variance is partitioned among differences between-individual (48%), within-individuals (40%), and by calendar year of sub-adulthood (12%). Our data reveal substantial ontogenetic and individual dietary variation within a white shark population.

PLoS ONE↗
USGS2015

Mineral potential for sediment-hosted copper deposits in the Islamic Republic of Mauritania (phase V, deliverable 75)

The presence of Neoproterozoic through Cambrian, continental, siliciclastic sedimentary rocks interbedded with dolomitic carbonates, shales, and glacial tillites similar to the Katanga Supergroup host rocks of the Central African Copperbelt and other sediment-hosted copper-bearing Proterozoic sequences worldwide, is first order criteria for consideration of the Neoproterozoic units of the Taoudeni Basin in Mauritania as prospective for sediment-hosted copper deposits. Review of the National Mineral Occurrences Database (Marsh and Anderson, 2015) and previous literature suggest that only a handful of small sediment-hosted copper occurrences have been found to date in Mauritania and that the resource potential for this deposit type is low. In the northern Taoudeni Basin, the most important occurrence is at Taradent. This occurrence consists of three mineralized horizons in the lower Neoproterozoic Char Group in three outcrop areas separated by alluvium over a strike length of 12 kilometers (km). The most extensively mineralized horizon consists of malachite and disseminated copper sulfides, and is concentrated at the base of a dolomitic interval, consistent with a reduced faciestype sediment-hosted copper deposit model. Additional and poorly described copper occurrences in the Taoudeni Basin margin sedimentary rocks in northeastern Mauritania, such as Chegga Guettatira and Sidi Bara, may be sediment-hosted copper occurrences and extend the potential throughout this portion of the Basin. Additional potential for sediment-hosted copper deposits is indicated in reports by the British Geological Survey (BGS; Gunn and others, 2004) and BRGM (Salpeteur, 2005) in the Neoproterozoic-Cambrian sedimentary rocks (Teniagouri Group) of the central and southern Taoudeni Basin at a number of occurrences in the vicinity of Fouges, Weringuel, and Gig Zig. These occurrences exhibit characteristics consistent with a reduced-facies-type sediment-hosted copper deposit model and based on correlation of similar host rocks extend the potential throughout the entire Taoudeni Basin margin. Very poorly described copper occurrences in the northeastern and southeastern part of the Basin at Kreb en Naga, Kreb en Naga SW, Berbere, Dhar Nema, Dhar Nema 2, Saile, and Nejam-Medroume all are described as occurring in sedimentary rocks and are hosted by or are in close proximity to voluminous outcrops of Jurassic microgabbros (also referred to as dolerite or diabase). Uncertainty exists as to whether they are sediment-hosted copper occurrences. They are likely more closely analogous to copper occurrences associated with mafic igneous activity. The determination of whether reported copper occurrences and associated sedimentary rocks at Kreb en Naga and Kreb en Naga SW in the northeastern Taoudeni Basin and the Dhar Nema occurrences in the southeastern Taoudeni are permissive of sediment-hosted copper mineralization was inconclusive due to the absence of copper showings. While sedimentary host rocks at these locations must be broadly considered permissive, the absence of other favorable geologic features in these areas indicates that the potential for mineral deposits of this type is low. The widespread presence of mafic sills and dikes of Jurassic age throughout these areas and descriptions of associated minor copper mineralization suggests that many of the copper occurrences in these areas are not of the sediment-hosted copper type. Highly speculative potential exists in the Coastal Basin for Revett-type copper deposits in unexposed Jurassic-Cretaceous sandstones that may contain structural traps with gas accumulations. Eocene continental red bed sandstones of the Gorgol Formation, where overlain by the shallow marine sedimentary rocks of the Rinndiao Formation, represent an additional low potential rock sequence within the southeastern portion of the Coastal Basin that is permissive of sediment-hosted copper deposits. Field examinations of outcrop areas in the vicinity of many of the known occurrences were performed in late 2007 to provide additional criteria for evaluating the potential for this type of mineralization in Mauritania. In general, the geographic coordinates of occurrences are imprecise and many of the occurrences could not be located. Examination of outcrops of the Char Group in the Taradent area confirms the permissive nature of these rocks for reduced-facies-type sediment-hosted copper deposits. Inspection of weak copper mineralization hosted by black shales at several occurrences in the Gadel-Maylime area confirms that these occurrences are also of the reduced-faciestype and that the black and green shales of the Bouly and Ould Yenje Formations are permissive. Reported copper analyses up to 0.75 percent copper at Taradent and a single analysis of mineralized shale in the Gadel-Maylime area containing 0.55 percent copper indicate that low grade ore material exists at these locations. However indications that such copper grades are continuous over significant intervals and present in large tonnages are lacking. Although mineral occurrence data and descriptive geological information are adequate to delineate areas favorable for sediment-hosted copper deposits, this review indicates that potential for this type of deposit in Mauritania is low.

Open-File Report↗
USGS2021

Phylogeographic genetic diversity in the white sucker hepatitis B Virus across the Great Lakes Region and Alberta, Canada

Hepatitis B viruses belong to a family of circular, double-stranded DNA viruses that infect a range of organisms, with host responses that vary from mild infection to chronic infection and cancer. The white sucker hepatitis B virus (WSHBV) was first described in the white sucker (Catostomus commersonii), a freshwater teleost, and belongs to the genus Parahepadnavirus. At present, the host range of WSHBV and its impact on fish health are unknown, and neither genetic diversity nor association with fish health have been studied in any parahepadnavirus. Given the relevance of genomic diversity to disease outcome for the orthohepadnaviruses, we sought to characterize genomic variation in WSHBV and determine how it is structured among watersheds. We identified WSHBV-positive white sucker inhabiting tributaries of Lake Michigan, Lake Superior, Lake Erie (USA), and Lake Athabasca (Canada). Copy number in plasma and in liver tissue was estimated via qPCR. Templates from 27 virus-positive fish were amplified and sequenced using a primer-specific, circular long-range amplification method coupled with amplicon sequencing on the Illumina MiSeq. Phylogenetic analysis of the WSHBV genome identified phylogeographical clustering reminiscent of that observed with human hepatitis B virus genotypes. Notably, most non-synonymous substitutions were found to cluster in the pre-S/spacer overlap region, which is relevant for both viral entry and replication. The observed predominance of p1/s3 mutations in this region is indicative of adaptive change in the polymerase open reading frame (ORF), while, at the same time, the surface ORF is under purifying selection. Although the levels of variation we observed do not meet the criteria used to define sub/genotypes of human and avian hepadnaviruses, we identified geographically associated genome variation in the pre-S and spacer domain sufficient to define five WSHBV haplotypes. This study of WSHBV genetic diversity should facilitate the development of molecular markers for future identification of genotypes and provide evidence in future investigations of possible differential disease outcomes.

Alberta, Michigan, Minnesota, Ohio, Wisconsin↗
USGS1985

Interspecific competition among Hawaiian forest birds

The object of this study was to determine whether interspecific competition modified local geographic distribution, after taking into account the effect of habitat structure. The tendencies for 14 passerine birds to have positive or negative associations were examined, using 7861 sample points in seven native forests on the islands of Hawaii, Maui, and Kauai. All birds were at least partly insectivorous and were fairly common in forested areas, although some fed chiefly on nectar or fruit. Species—pairs were classified as primary or secondary potential competitors based on general dietary similarity. To evaluate the association between species and to account for the effect of individual species habitat preferences, partial correlations were computed for each species—pair in a study area from the simple correlations between the species and 26 habitat variables plus two quadratic terms to represent nonlinearity. The partial correlations represented a short—term ("instantaneous") assessment of the strength of competitive interactions, and did not reflect the accumulation of competitive displacement through time. Of 170 partial correlations in the analysis, only 10 indicated significant negative association. The general pattern was of positive association (76 significantly positive partials), which probably resulted from flocking and from attraction of birds to areas of resource superabundance. Two species showed consistent patterns of negative partial correlations over several adjacent study areas, the Japanese White—eye/Iiwi in montane Hawaii, and the Japanese White—eye/Elepaio in windward Hawaii; both patterns could be reasonably attributed to direct competition. Species—pairs were grouped by the native or exotic status of the component species. Native/exotic pairs had a significantly greater proportion of negative partial correlations (37%) than either native/native pairs (8%) or exotic/exotic pairs (0%). This pattern was consistent across the seven study areas and appeared to reflect the occurrence of interspecific competition along a broad and diffuse ecological "front" between a co—evolved native avifauna and recently introduced exotic species. The role of competition in the pattern was corroborated by the significantly higher proportion of negative partial correlations among species—pairs of primary potential competitors than among those of secondary potential competitors. Our results suggested that °47% of the primary potential competitors among native/exotic species—pairs may experience at least small depressions in local population density due to competition. Although the negative correlations were for the most part small (average negative r = 0.06), one species could eventually replace another as spatial displacement accumulated through time. The Japanese White—eye appeared to have a principal role in native/exotic interactions, with 62% of the partial correlations between it and native primary potential competitor species being negative. Noteworthy implications were that (1) it was important to account for the habitat responses of individual species when studying the role of interspecific competition in modifying small—scale geographic distribution; (2) competition was frequently sporadic in its geographic occurrence and in the species affected, thus supporting Wiens' (1977) theory of competition; and (3) as a consequence, the role of interspecific competition in modifying distribution may be difficult to detect statistically with small data sets.

Hawaii↗
USGS2016

Regional analysis of social characteristics for evacuation resource planning: ARkStorm scenario

Local planning is insufficient for regional catastrophes; regional exercises are needed to test emergency plans and decision-making structures. The ARkStorm scenario would trigger a mass evacuation that would be complicated by the social characteristics of populations [e.g., vehicle ownership, age, poverty, English language limitation (ELL), and shelter needs]. Land cover data and dasymetric mapping improves the allocation of residential populations and their social characteristics to the ARkStorm flood zone in 21 counties in California. Numbers and concentrations of county, urban, and rural residents exposed to flooding as well as populations in and out of the scenario flood zone are profiled. The results inform mass evacuation planning by providing a means to (1) examine the sufficiency of mutual aid agreements, (2) underscore planning for carless populations, and (3) tailor multilingual communication strategies. The various geographical distinctions emphasize different challenges throughout the region. It will be important to investigate behavioral responses to warnings, identify evacuation constraints (e.g., shelter capacity versus need), and obtain comparable data on transient populations.

Natural Hazards Review↗
USGS2014

Radar analysis of fall bird migration stopover sites in the northeastern U.S.

The national network of weather surveillance radars (WSR-88D) detects flying birds and is a useful remote-sensing tool for ornithological study. We used data collected during fall 2008 and 2009 by 16 WSR-88D radars in the northeastern U.S. to quantify the spatial distribution of landbirds during migratory stopover. We geo-referenced estimates based on radar reflectivity, of the density of migrants aloft at their abrupt evening exodus from daytime stopover sites, to the approximate locations from which they emerged. We classified bird stopover use by the magnitude and variation of radar reflectivity across nights; areas were considered “important” stopover sites for conservation if bird density was consistently high. We developed statistical models that predict potentially important stopover sites across the region, based on land cover, ground elevation, and geographic location. Large areas of regionally important stopover sites were located along the coastlines of Long Island Sound, throughout the Delmarva Peninsula, in areas surrounding Baltimore and Washington, along the western edge of the Adirondack Mountains, and within the Appalachian Mountains of southwestern Virginia and West Virginia. Locally important stopover sites generally were associated with deciduous forests embedded within landscapes dominated by developed or agricultural lands, or near the shores of major water bodies. Preserving or enhancing patches of natural habitat, particularly deciduous forests, in developed or agricultural landscapes and along major coastlines could be a priority for conservation plans addressing the stopover requirements of migratory landbirds in the northeastern U.S. Our maps of important stopover sites can be used to focus conservation efforts and can serve as a sampling frame for fieldwork to validate radar observations or for ecological studies of landbirds on migratory stopover.

The Condor↗
USGS2020

Genomes reveal genetic diversity of Piscine orthoreovirus in farmed and free-ranging salmonids from Canada and USA

Piscine orthoreovirus (PRV-1) is a segmented RNA virus which is commonly found in salmonids in the Atlantic and Pacific Oceans. PRV-1 causes the Heart and Skeletal Muscle Inflammation (HSMI) disease in Atlantic salmon and is associated with several other disease conditions. Previous phylogenetic studies of genome segment 1 (S1) identified four main genogroups of PRV-1 (S1 genogroups I – IV). The goal of the present study was to use Bayesian phylogenetic inference to expand our understanding of the spatial, temporal and host patterns of PRV-1 from the waters of the northeast Pacific. To that end, we determined the coding genome sequences of 14 PRV-1 samples that were selected to improve our knowledge of genetic diversity across a broader temporal, geographic and host range, including the first reported genome sequences from the northwest Atlantic (Eastern Canada). Nucleotide and amino acid sequences of the concatenated genomes and their individual segments revealed that established sequences from the northeast Pacific were monophyletic in all analyses. Bayesian inference phylogenetic trees of S1 sequences using BEAST and MrBayes also found that sequences from the northeast Pacific grouped separately from sequences from other areas. One PRV-1 sample (WCAN_BC17_AS_2017) from an escaped Atlantic salmon, collected in British Columbia but derived from Icelandic broodstock, grouped with other S1 sequences from Iceland. Our concatenated genome and S1 analysis demonstrated that PRV-1 from the northeast Pacific is genetically distinct but descended from PRV-1 from the North Atlantic. However, the analyses were inconclusive as to the timing and exact source of introduction into the northeast Pacific, either from eastern North America or European waters of the North Atlantic. There was no evidence that PRV-1 was evolving differently between free-ranging Pacific Salmon and farmed Atlantic Salmon. The northeast Pacific PRV-1 sequences fall within genogroup II based on the classification of Garseth et al. (2013), which also includes North Atlantic sequences from Eastern Canada, Iceland and Norway. The additional full genome sequences herein strengthen our understanding of phylogeographical patterns related to the northeast Pacific, but a more balanced representation of full PRV-1 genomes from across its range, as well additional sequencing of archived samples, are still needed to better understand global relationships including potential transmission links among regions.

Faroe Islands↗
USGS2018

Flood-inundation maps for the Withlacoochee River From Skipper Bridge Road to St. Augustine Road, within the City of Valdosta, Georgia, and Lowndes County, Georgia

Digital flood-inundation maps for a 12.6-mile reach of the Withlacoochee River from Skipper Bridge Road to St. Augustine Road (Georgia State Route 133) were developed to depict estimates of the areal extent and depth of flooding corresponding to selected water levels (stages) at the U.S. Geological Survey (USGS) streamgage at Withlacoochee River at Skipper Bridge Road, near Bemiss, Ga. (023177483). Real-time stage information from this streamgage can be used with these maps to estimate near real-time areas of inundation. The forecasted peak-stage information for the USGS streamgage at Withlacoochee River at Skipper Bridge Road, near Bemiss, Ga. (023177483), can be used in conjunction with the maps developed for this study to show predicted areas of flood inundation. A one-dimensional step-backwater model was developed using the U.S. Army Corps of Engineers Hydrologic Engineer-ing Center’s River Analysis System (HEC–RAS) software for the Withlacoochee River and was used to compute flood profiles for a 12.6-mile reach of the Withlacoochee River. The hydraulic model was then used to simulate 23 water-surface profiles at 1.0-foot (ft) intervals at the Withlacoochee River near the Bemiss streamgage. The profiles ranged from the National Weather Service action stage of 10.7 ft, which is 131.0 ft above the North American Vertical Datum of 1988 (NAVD 88), to a stage of 32.7 ft, which is 153.0 ft above NAVD 88. The simulated water-surface profiles were then combined with a geographic information system digital elevation model—derived from light detection and ranging (lidar) data having a 4.0-ft horizontal resolution—to delineate the area flooded at each 1.0-ft interval of stream stage.

Georgia↗
USGS2007

Precipitation zones of west-central Nevada

Whether Nevada can sustain its fast rate of growth depends in part on accurately quantifying the amount of water that is available, including precipitation. The Precipitation-Zone Method (PZM) is a way of estimating mean annual precipitation at any point. The PZM was developed using data from west-central Nevada and northeastern California, but preliminary analysis indicates it can be applied to the entire state. Patterns in the spatial distribution of precipitation were identified by mapping station locations and plotting 1971-2000 precipitation normals versus station elevation. Precipitation zones are large areas where precipitation is linearly related to elevation. Four precipitation zones with different linear relations were delineated; these zones cover much of west-central Nevada. Regression equations with adjusted R2 values of 0.89 to 0.95 were developed for each zone. All regression equations estimate similar precipitation rates at 4,000 feet, but the slopes of the regression equations become progressively shallower to the south. A geographic information system, 30-meter digital elevation model, and the regression equations were used to estimate the distribution and volumes of precipitation in each zone and in hydrographic areas of the Walker River Basin. Comparison between the PZM and Parameter-elevation Regressions on Independent Slopes Model (PRISM) indicate PRISM estimates are linearly related to elevation at low elevations in each zone, but PRISM estimates become non-linear at high elevations and are up to 2.5 times greater than the normals. However, PRISM under-estimates more than it over-estimates precipitation compared to the PZM. The PZM estimated the same or larger volumes of precipitation compared to PRISM in three of the zones, and the larger volumes mostly were from areas that receive greater than 15 inches/year of precipitation. Additional work is needed to accurately estimate mean annual precipitation throughout Nevada.

Nevada↗
USGS2014

Integrating recent land cover mapping efforts to update the National Gap Analysis Program's species habitat map

Over the past decade, great progress has been made to develop national extent land cover mapping products to address natural resource issues. One of the core products of the GAP Program is range-wide species distribution models for nearly 2000 terrestrial vertebrate species in the U.S. We rely on deductive modeling of habitat affinities using these products to create models of habitat availability. That approach requires that we have a thematically rich and ecologically meaningful map legend to support the modeling effort. In this work, we tested the integration of the Multi-Resolution Landscape Characterization Consortium's National Land Cover Database 2011 and LANDFIRE's Disturbance Products to update the 2001 National GAP Vegetation Dataset to reflect 2011 conditions. The revised product can then be used to update the species models. We tested the update approach in three geographic areas (Northeast, Southeast, and Interior Northwest). We used the NLCD product to identify areas where the cover type mapped in 2011 was different from what was in the 2001 land cover map. We used Google Earth and ArcGIS base maps as reference imagery in order to label areas identified as "changed" to the appropriate class from our map legend. Areas mapped as urban or water in the 2011 NLCD map that were mapped differently in the 2001 GAP map were accepted without further validation and recoded to the corresponding GAP class. We used LANDFIRE's Disturbance products to identify changes that are the result of recent disturbance and to inform the reassignment of areas to their updated thematic label. We ran species habitat models for three species including Lewis's Woodpecker ( Melanerpes lewis ) and the White-tailed Jack Rabbit ( Lepus townsendii ) and Brown Headed nuthatch ( Sitta pusilla ). For each of three vertebrate species we found important differences in the amount and location of suitable habitat between the 2001 and 2011 habitat maps. Specifically, Brown headed nuthatch habitat in 2011 was −14% of the 2001 modeled habitat, whereas Lewis's Woodpecker increased by 4%. The white-tailed jack rabbit ( Lepus townsendii ) had a net change of −1% (11% decline, 10% gain). For that species we found the updates related to opening of forest due to burning and regenerating shrubs following harvest to be the locally important main transitions. In the Southeast updates related to timber management and urbanization are locally important.

The International Archives of the Photogrammetry, ↗
USGS2018

Global Earthquake Model (GEM) Risk Map

The Global Earthquake Risk Map (v2018.1) comprises four global maps. The main map presents the geographic distribution of average annual loss (USD) normalized by the average construction costs of the respective country (USD/m2 due to ground shaking in the residential, commercial and industrial building stock, considering contents, structural and non-structural components. The normalized metric allows a direct comparison of the risk between countries with widely different construction costs. It does not consider the effects of tsunamis, liquefaction, landslides, and fires following earthquakes. The loss estimates are from direct physical damage to buildings due to shaking, and thus damage to infrastructure or indirect losses due to business interruption are not included. The Global Earthquake Hazard Map depicts the geographic distribution of the Peak Ground Acceleration (PGA) with a 10% probability of being exceeded in 50 years, computed for reference rock conditions (shear wave velocity of 760-800 m/s). The Global Exposure Map depicts the geographic distribution of residential, commercial and industrial buildings. The Global Seismic Fatalities Map depicts an estimate of average annual human losses due to earthquake-induced structural collapse of buildings. The results for human losses do not consider indirect fatalities such as those from post­ earthquake epidemics. The average annual losses and number of buildings are presented on a hexagonal grid, with a spacing of 0.30 x 0.34 decimal degrees (approximately 1,000 km2 at the equator). The average annual losses were computed using the event-based calculator of the OpenQuake engine, an open-source software for seismic hazard and risk analysis developed by the GEM Foundation. The seismic hazard, exposure and vulnerability models employed in these calculations were provided by national institutions, or developed within the scope of regional programs or bilateral collaborations. These global maps and the underlying databases are based on best available and publicly accessible datasets and models. Due to possible limitations in the model, regions portrayed with low risk may experience potentially damaging earthquakes. The GEM Risk Map is intended to be a dynamic product, which will be updated when new datasets and models become available. Updated versions of the hazard, exposure, and average annual losses will be released on a regular basis. Additional metrics for each country can be explored at globalquakemodel.org/gem.

Report↗
USGS1999

Temporal and geographic variation in fish communities of lower Cook Inlet, Alaska

Nearshore and shelf fish communities were studied in three areas of lower Cook Inlet, Alaska: the Barren Islands (oceanic and well-mixed waters), Kachemak Bay (mixed oceanic waters with significant freshwater runoff), and Chisik Island (estuarine waters). Fish were sampled with beach seines (n=413 sets) and midwater trawls (n=39 sets). We found that lower Cook Inlet supported a diverse nearshore fish community of at least 52 species. Fifty of these species were caught in Kachemak Bay, 24 at Chisik Island, and 12 at the Barren Islands. Pacific sand lance dominated Barren Islands and Kachemak Bay nearshore habitats, comprising 99% and 71% of total individuals, respectively. The nearshore Chisik Island fish community was not dominated by any one species; instead it exhibited higher diversity. These spatial differences appeared linked to local oceanographic regimes and sediment influx. Analysis of historical data revealed that the nearshore Kachemak Bay fish community changed significantly between 1976 and 1996, showing increased diversity and abundance in several taxa, notably gadids, salmonids, pleuronectids, and sculpins. Decadal differences appeared to be related to large-scale climate changes in the North Pacific. Catches of most taxa peaked in May-August, and were low during other months of the year. Several species were present for only part of the summer. Species composition of seine catches differed significantly between consecutive high and low tides, but not between consecutive sets or years. Midwater trawls took 26 species, 14 of which were present in Kachemak Bay, 19 near Chisik Island, and 7 at the Barren Islands. Community structures in shelf and nearshore waters were similar: diversity was high and abundance low at Chisik Island, whereas a few abundant species dominated at both Kachemak Bay and the Barren Islands. In addition, the low fish abundance near Chisik Island appeared to be related to declining seabird numbers at this colony.

Fishery Bulletin↗
USGS2017

Smartphone technologies and Bayesian networks to assess shorebird habitat selection

Understanding patterns of habitat selection across a species’ geographic distribution can be critical for adequately managing populations and planning for habitat loss and related threats. However, studies of habitat selection can be time consuming and expensive over broad spatial scales, and a lack of standardized monitoring targets or methods can impede the generalization of site-based studies. Our objective was to collaborate with natural resource managers to define available nesting habitat for piping plovers ( Charadrius melodus ) throughout their U.S. Atlantic coast distribution from Maine to North Carolina, with a goal of providing science that could inform habitat management in response to sea-level rise. We characterized a data collection and analysis approach as being effective if it provided low-cost collection of standardized habitat-selection data across the species’ breeding range within 1–2 nesting seasons and accurate nesting location predictions. In the method developed, >30 managers and conservation practitioners from government agencies and private organizations used a smartphone application, “iPlover,” to collect data on landcover characteristics at piping plover nest locations and random points on 83 beaches and barrier islands in 2014 and 2015. We analyzed these data with a Bayesian network that predicted the probability a specific combination of landcover variables would be associated with a nesting site. Although we focused on a shorebird, our approach can be modified for other taxa. Results showed that the Bayesian network performed well in predicting habitat availability and confirmed predicted habitat preferences across the Atlantic coast breeding range of the piping plover. We used the Bayesian network to map areas with a high probability of containing nesting habitat on the Rockaway Peninsula in New York, USA, as an example application. Our approach facilitated the collation of evidence-based information on habitat selection from many locations and sources, which can be used in management and decision-making applications.

U.S Atlantic Coast↗
USGS2025

Non-native bird populations respond differently to their environment and exhibit shifts in ecological niche limits across continents

Aim The degree to which species' niches remain stable over space and time–the niche conservatism hypothesis–is critical for predicting species' responses to environmental change. Tests of this hypothesis typically focus on changes in niche centroids and boundaries. An outstanding question is whether species' environmental associations differ within the interior of their niche space–that is, across the full range of occupied conditions–in original versus novel geographic space. Location Europe and North America. Time Period 1997–2018. Major Taxa Studied Birds. Methods We used over 400,000 observations collected over 22 years and across 28 countries to explore whether two common songbird species—European starling ( Sturnus vulgaris ) and house sparrow ( Passer domesticus ) – exhibit niche conservatism between their native European and non-native North American ranges. We tested for niche conservatism via (1) an ordination approach that quantified change in niche shape and boundaries, and (2) generalised linear mixed effects models to quantify how abundance varied with the interaction between continent and climate or land cover variables. Results The ordination analysis indicated that both European starling and house sparrow exhibited niche conservatism between Europe and North America. However, abundance models revealed continental differences in how the species responded to temperature and land cover. The abundance models also revealed that areas with wetter conditions that were occupied by both species in their native European ranges were available but unoccupied in their non-native North American ranges (i.e., niche unfilling). Main Conclusions Our work demonstrates that species can exhibit apparent consistency in niche boundaries but varied abundance responses to the environment within niche boundaries. Expanding the study of niche conservatism to explore changes both at the edge of and within niche boundaries would improve the ability to assess and predict species' invasion risk or sensitivity to ongoing global change.

Diversity and Distributions↗
USGS2002

Estimating mean annual streamflow of rural streams in Kentucky

Mean annual streamflow ( Q a ), defined as the mean of the series of annual mean streamflow values, was determined for selected rural stream sites in Kentucky. Streamflow data for the available period of record through the 1999 water year (October 1, 1998-September 30, 1999) at 235 continuous-record streamflow-gaging stations with at least 5 years of record located in and adjacent to Kentucky were used in the analysis. Record-extension procedures were applied for selected gaging stations to reduce time-sampling error and, thus, improve estimates of the long-term Q a . Techniques to estimate the Q a at ungaged stream sites in Kentucky were developed. One-, two-, and three-variable regression equations that included total drainage area, station latitude minus 36 degrees, and mean basin elevation as explanatory variables were developed by use of ordinary- and generalized-least-squares regression. The three-variable regression equation has an approximate average standard error of prediction of 13.7 percent. The one- and two-variable equations exhibit geographical biases, and the indicated standard errors of prediction may poorly estimate the true prediction errors, depending upon the location in the State. Therefore, the three-variable equation should be used for estimating mean annual streamflow of rural streams in Kentucky whenever possible.

Water-Resources Investigations Report↗
USGS1997

Selected trace metals and organic compounds and bioavailability of selected organic compounds in soils, Hackberry Flat, Tillman County, Oklahoma, 1994-95

In 1995 the Oklahoma Department of Wildlife Conservation acquired a drained wetland in southwest Oklahoma known as Hackberry Flat. Following restoration by Wildlife Conservation the wetland will be used by migratory birds and waterfowl. If naturally occurring trace metals and residual organic compounds from agriculture and industry were present, they may have posed a potential biohazard and were a concern for Wildlife Conservation. The U. S. Geological Survey, in cooperation with Wildlife Conservation and the Oklahoma Geological Survey, examined the soils of Hackberry Flat to determine trace metal concentrations, presence of selected organic compounds, and the bioavailability of selected organic compounds in the soils. The purpose of this report is to present the data that establish the baseline concentrations of selected trace metals and organic compounds in the soils of Hackberry Flat prior to wetland restoration. Sampling and analysis were performed using two approaches. One was to collect soil samples and analyze the composition with standard laboratory practices. The second exposed composite soils samples to organic-free water and a semipermeable membrane device that mimics an organism and then analyzed the device. Ten soil samples were collected in 1994 to be analyzed for trace metals, organochlorine pesticides, and polychlorinated biphenyls. Soil samples tested for bioavailability of selected organic compounds were collected in 1995. Most of the 182 soil samples collected were from the center of every 40-acre quarter-quarter section owned by the Wildlife Conservation. The samples were grouped by geographical area with a maximum of 16 sample sites per group. Concentrations of most selected trace metals measured from soils in Hackberry Flat are within the range of mean concentrations measured in cultivated soils within the United States. Organochlorine pesticides, polychlorinated biphenyls, and polyaromatic hydrocarbons were not found at concentrations above the analytical detection levels and, if present, in the soil samples are at concentrations below the detection level of the analytical method used. Organochlorine pesticides, total polychlorinated biphenyls, and polyaromatic hydrocarbons were not detected in any of the semipermeable membrane devices at the analytical detection levels.

Oklahoma↗