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Corescan© Hyperspectral Core Imager Mark III (HCI-III) system data were acquired for hand samples, and subsequent billets made from the hand samples, collected during the U.S. Geological Survey (USGS) 2014, 2015, and 2016 field seasons in the Nabesna area of the eastern Alaska Range. This area contains exposed porphyry deposits and hand samples were collected throughout the region in support of the HyMap imaging spectrometer survey (https://doi.org/10.5066/F7DN435W) (Kokaly and others, 2017a). The HCI-III system consists of three different components. The first is an imaging spectrometer which collects reflectance data with a spatial resolution of approximately 500 nanometers (nm) for 514 spectral channels covering...
This data release comprises a dataset that contains sample collection information and microsatellite genotypes, and another dataset that contains single nucleotide polymorphism (SNP) genotypes with sample collection information for populations of white-tailed ptarmigan across the species' range. There is also an additional file (accession numbers.xlsx) linking samples to accession numbers in Genbank. This data was collected in order to address the following: The delineation of intraspecific units that are evolutionarily and demographically distinct is an important step in the development of species-specific management plans. Neutral genetic variation has served as the primary data source for delineating units for...
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The Gulf of Alaska is one of the most productive marine ecosystems on Earth, supporting salmon fisheries that alone provide nearly $1 billion per year in economic benefits to Southeast Alaska. Glaciers are central to many of the area’s natural processes and economic activities, but the rates of glacier loss in Alaska are among the highest on Earth, with a 26-36 percent reduction in total volume expected by the end of the century. This project brought together scientists and managers at a workshop to synthesize the impacts of glacier change on the region’s coastal ecosystems and to determine related research and monitoring needs. Collected knowledge shows that melting glaciers are expected to have cascading effects...
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Nine native taxa including Carex oligosperma, C. pauciflora, C. pellita, Chimaphila umbellata ssp. occidentalis, Draba densifolia, x Elyleymus hirtiflorus, Eriophorum vaginatum ssp. spissum, Impatiens ? capensis, and Rhus radicans are reported new to the known flora of the Yukon Territory. Eight introduced taxa are also reported as new to the known flora. Significant range extensions within the Territory are reported for 180 native and 17 introduced taxa. Comments are presented on three native taxa and two native taxa are deleted from the Territory.
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Ten native taxa including Arabis boivinii, Carex aquatilis ssp. stans, Descurainia incisa var. incisa, Draba lonchocarpa var. vestita, Isoetes maritima, Lepidium densiflorum var. macrocarpum, Malaxis paludosa, Phyllodoce X intermedia, Scirpus acutus, Stipa hymenoides and Taraxacum carneocoloratum are reported new to the known flora of the Yukon Territory. Three introduced taxa including Centaurea cyanus, Lolium perenne ssp. multiflorum, Rheum rhaponticum and Sorbaria sorbifolia are also reported as new to the known flora. Significant range extensions within the Territory are reported for 127 native and 21 introduced taxa and comments are presented on four native taxa. Of these, 10 native and three introduced are...
Both Mule Deer (Odocoileus hemionus) and White-tailed Deer (Odocoileus virginianus) have colonized the southern half of the Yukon in recent decades. Mule Deer have attained a continuous distribution in suitable habitats, White-tailed Deer have remained rare. Deer habitats are largely open, south-facing grassy slopes bordered by aspen, sites of recent forest fires, and cultivated hay fields. Many sightings have been reported by the general public. These have been supplemented by interviews of native elders and other long-time residents and a literature search. Mule Deer first appeared in the Yukon in the late 1930s to early 1940s and by the 1980s had reached the latitude of Dawson (64 degree N) and crossed into Alaska...
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Approximately 1,900 line square kilometers of imagery were collected using a HyMap™ sensor (Cocks and others, 1998) mounted on a modified Piper Navajo aircraft. The aircraft was flown at an altitude of approximately 5,050 m (3,480 m above the mean ground surface elevation of 1570 m) resulting in average ground spatial resolution of 6.7 m. Solar elevation and azimuth angles ranged from 42.0-48.3° (average 46.2°) and 134.2-182.4° (average 155°), respectively. HyMap measured reflected sunlight in 126 narrow channels that cover the wavelength region of 455 to 2,483 nm. Data were delivered by the operators of the sensor (HyVista Corp., Australia) in units of radiance (data are available in Kokaly and others, 2017)....
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Reflectance data from HyMap™ were processed using the Material Identification and Characterization Algorithm (MICA), a module of the USGS PRISM (Processing Routines in IDL for Spectroscopic Measurements) software (Kokaly, 2011), programmed in Interactive Data Language (IDL; Harris Geospatial Solutions, Broomfield, Colorado). The HyMap reflectance data are provided and described in this data release. MICA identifies the spectrally predominant mineral(s) in each pixel of imaging spectrometer data by comparing continuum-removed spectral features in the pixel’s reflectance spectrum to continuum-removed absorption features in reference spectra of minerals, vegetation, water, and other materials. Linear continuum removal...
Animal and plant remains, some associated with prehistoric artefacts, were collected in freezing caverns (glacieres) of northern Yukon Territory. Radiocarbon dates show that the oldest remains are Middle Wisconsinan (ca. 38 000 BP). The absence of material of Late Wisconsinan age likely indicates that the caves were infilled by ice during this cold period. Climate warming and ice melting during the Holocene allowed animals and prehistoric hunters to regularly visit these caves. Ice plugs were evidently smaller during the early Holocene than they are now.
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Mineral predominance data were a derivative product from the Corescan© reflectance data. Corescan Hyperspectral Core Imager Mark III (HCI-III) system data were acquired for hand samples, and subsequent billets made from the hand samples, collected during the U.S. Geological Survey (USGS) 2014, 2015, and 2016 field seasons in the Nabesna area of the eastern Alaska Range. This area contains exposed porphyry deposits and hand samples were collected throughout the region in support of the HyMap imaging spectrometer survey (https://doi.org/10.5066/F7DN435W) (Kokaly and others, 2017a). The HCI-III system consists of three different components. The first is an imaging spectrometer which collects reflectance data with a...
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The U.S. Geological Survey (USGS) Data at Risk (DaR) team partnered with the Forest and Rangeland Ecosystem Science Center (FRESC) to preserve and release a subset of their golden eagle telemetry data. In the 1990’s, researchers from what is now FRESC worked with Boise State University (BSU) and collected telemetry and ground observation data that documented the local and migratory movements and behaviors of golden eagles. Over the course of this study 21 golden eagles in the conterminous western US were captured and marked with Argos platform terminal transmitters (PTTs) and tracked by satellite as they moved between breeding and wintering locations (individuals marked with Argos PTTs and tracked by satellite are...
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Detailed geologic mapping and sample collection was conducted in rare bedrock exposures of the Denali fault zone during the summer months of 2013, 2014, and 2015 by the U.S. Geological Survey. Data include measurements of structural geologic orientations and documentation of fault zone and host rock characteristics. Representative samples were selected for measurements of fault vein attributes and electron backscatter diffraction studies to characterize deformation mechanisms. All station locations, pertinent sample information, and associated data are included in this data release.
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Rates of glacier loss in the northern Pacific coastal temperate rainforest (PCTR) are among the highest on Earth. These changes in glacier volume and extent will affect the flow and chemistry of coastal rivers, as well as the nearshore marine ecosystem of the Gulf of Alaska (GOA). Runoff from glaciers accounts for about half of the land-to-ocean movement of freshwater into the GOA, strongly influencing the freshwater and marine ecosystems along the coast. Runoff from glaciers, for example, significantly impacts the water temperature and clarity of aquatic habitats, which are important conditions for salmon reproduction. Moreover, runoff from glaciers along the GOA is an important factor in the structure of the...
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We studied kill rates by wolves (Canis lupus) on a rapidly growing moose population in the east-central Yukon. We added these data to the cumulative functional response curve obtained in other North American wolf studies. Our kill rates are higher than those predicted at low moose densities. The kill rate increases rapidly, reaching 2.4 moose per wolf per 100 days at 0.26 moose/km2 and remains constant at this level. No data are available below 0.2 moose/km2 to indicate the shape of the ascending curve. Based on moose distribution and the low prey-switching ability of wolves, we suggest that the functional response curve is of type II. Our wolf predation rate model predicts that moose are held to a low density equilibrium...
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We studied the kill rate by wolves (Canis lupus) after a large-scale wolf removal when populations of wolves, moose (Alces alces), and woodland caribou (Rangifer tarandus caribou) were all increasing. We followed a total of 21 wolf packs for 4 winters, measuring prey selection, kill rates, and ecological factors that could influence killing behavior. Wolf predation was found to be mainly additive on both moose and caribou populations. Kill rates by individual wolves were inversely related to pack size and unrelated to prey density or snow depth. Scavenging by ravens decreased the amount of prey biomass available for wolves to consume, especially for wolves in smaller packs. The kill rate by wolves on moose calves...
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Imaging spectrometer (hyperspectral) data were collected using the HyMap™ sensor over the Nabesna Area of Interest (AOI) in the eastern Alaska Range, July 14 and July 21, 2014. The primary study area was a remote part of the eastern Alaska Range where porphyry deposits are exposed. The HyMap imaging spectrometer measured reflected sunlight in 126 narrow channels spanning the 0.4 to 2.5 micron wavelength region of the electromagnetic spectrum. The data were collected at a nominal 6-m ground-instantaneous field of view (GIFOV). A total 1,900 square kilometers were collected. This data release provides flight line data for the survey and a report describing the dataset and procedures.
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A map of the wavelength position of the white mica 2,200 nanometer (nm) Al-OH absorption feature was compiled for a region of Nabesna, Alaska, using HyMap™ reflectance data provided and described in this data release. White mica wavelength position was computed for each pixel with spectrally predominant muscovite or illite. The computation was made using a function of the USGS PRISM (Processing Routines in IDL for Spectroscopic Measurements) software (Kokaly, 2011), programmed in Interactive Data Language (IDL; Harris Geospatial Solutions, Broomfield, Colorado). The PRISM function applies linear continuum-removal (Clark and Roush, 1984) to the 2,200 nm feature and fits a parabola to three channels: the channel...
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Imaging spectrometer (hyperspectral) data were collected using the HyMap™ sensor over the Nabesna Area of Interest (AOI) in the eastern Alaska Range, July 14 and July 21, 2014. The primary study area was a remote part of the eastern Alaska Range where porphyry deposits are exposed. The HyMap imaging spectrometer measured reflected sunlight in 126 narrow channels spanning the 0.4 to 2.5 micron wavelength region of the electromagnetic spectrum. The data were collected at a nominal 6-m ground-instantaneous field of view (GIFOV). A total 1,900 square kilometers were collected. This data release provides flight line data for the survey and a report describing the dataset and procedures.
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Imaging spectrometer (hyperspectral) data were collected using the HyMap™ sensor over the Nabesna Area of Interest (AOI) in the eastern Alaska Range, July 14 and July 21, 2014. The primary study area was a remote part of the eastern Alaska Range where porphyry deposits are exposed. The HyMap imaging spectrometer measured reflected sunlight in 126 narrow channels spanning the 0.4 to 2.5 micron wavelength region of the electromagnetic spectrum. The data were collected at a nominal 6-m ground-instantaneous field of view (GIFOV). A total 1,900 square kilometers were collected. This data release provides flight line data for the survey and a report describing the dataset and procedures.
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A hormonal-challenge protocol was used to compare the stress response of males of Arctic ground squirrels and red squirrels during the breeding season (May). These squirrels live in the same boreal forest of the Yukon, but have very different life histories and utilize the forest in markedly different ways. Red squirrels had levels of total cortisol, maximum corticosteroid-binding capacity, and free cortisol that were 5, 7, and 2 times, respectively, those of Arctic ground squirrels. Red squirrels were resistant to suppression by an artificial glucocorticoid, dexamethasone (DEX); Arctic ground squirrels were not. Cortisol levels in red squirrels responded slowly but continuously to the ACTH injection; Arctic ground...
map background search result map search result map From Icefield to Ocean: Glacier Change Impacts to Alaska’s Coastal Ecosystems Assessing Links between Glaciers and the Northern Pacific Coastal Temperate Rainforest Ecosystem Contrasting stress response of male arctic ground squirrels and red squirrels New records of vascular plants in the Yukon Territory II Kill rate by wolves on moose in the Yukon Wolf functional response and regulation of moose in the Yukon New records of vascular plants in the Yukon territory III Calibration01 Calibration03 Run08 Imaging spectrometer reflectance data for Nabesna, Alaska Mineral predominance map for Nabesna, Alaska, derived from imaging spectrometer reflectance data White mica wavelength position map for Nabesna, Alaska, derived from imaging spectrometer reflectance data LaserProfiler MineralPredominance Golden Eagle (Aquila chrysaetos) Satellite Telemetry and Observational Data, Western North America, 1993-1997 Denali Fault Zone Field, Microvein, and Microbeam Data, Kluane Ranges, Yukon, Canada Wolf functional response and regulation of moose in the Yukon LaserProfiler MineralPredominance Calibration03 Calibration01 Run08 Imaging spectrometer reflectance data for Nabesna, Alaska Mineral predominance map for Nabesna, Alaska, derived from imaging spectrometer reflectance data White mica wavelength position map for Nabesna, Alaska, derived from imaging spectrometer reflectance data Denali Fault Zone Field, Microvein, and Microbeam Data, Kluane Ranges, Yukon, Canada Kill rate by wolves on moose in the Yukon Contrasting stress response of male arctic ground squirrels and red squirrels New records of vascular plants in the Yukon Territory II New records of vascular plants in the Yukon territory III From Icefield to Ocean: Glacier Change Impacts to Alaska’s Coastal Ecosystems Assessing Links between Glaciers and the Northern Pacific Coastal Temperate Rainforest Ecosystem Golden Eagle (Aquila chrysaetos) Satellite Telemetry and Observational Data, Western North America, 1993-1997