Skip to main content
Advanced Search

Filters: Tags: Yukon Territory (X) > Types: Map Service (X)

19 results (82ms)   

Filters
Date Range
Extensions
Types
Contacts
Categories
Tag Types
Tag Schemes
View Results as: JSON ATOM CSV
thumbnail
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...
thumbnail
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.
thumbnail
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...
thumbnail
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...
thumbnail
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...
thumbnail
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.
thumbnail
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...
thumbnail
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...
thumbnail
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...
thumbnail
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...
thumbnail
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...
thumbnail
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...
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service, Shapefile; Tags: Alaska, Alaska, Alaska Range, Bond Creek, Canada, All tags...
thumbnail
Approximately 1,900 square kilometers of imagery were collected from July 14 to July 21, 2014 using a HyMap™ sensor (Cocks and others, 1998) mounted on a modified Piper Navajo aircraft. The survey area covered parts of the Wrangell and Nutzotin Mountains in the eastern Alaska Range near Nabesna, Alaska. The aircraft was flown at an altitude of approximately 5,050 meters (m) (3,480 m above the mean ground surface elevation of 1570 m) resulting in average ground spatial resolution of 6.7 m. HyMap measured reflected sunlight in 126 narrow channels that cover the wavelength region of 455 to 2,483 nanometers (nm). Data were delivered by the operators of the sensor (HyVista Corp., Australia) in units of radiance (Kokaly...
thumbnail
There are few quick, precise indices for predicting population size of semifossorial mammals. We assessed the utility of powder-tracing and infrared thermal imaging to predict population size in the Arctic ground squirrel (Spermophilus parryii) in the boreal forest of southwestern Yukon. Density estimated from livetrapping was strongly and linearly correlated with both indices (r = 0.81 for powder-tracking; r = 0.91 for infrared imaging). The slope of the relationship between density and the infrared index (0.10) deviated from a slope of 1. The slope of the relationship between density and the powder-tracking index (0.82) did not deviate from a slope of 1, but our power to detect departures from this slope using...
thumbnail
The distribution and prevalence of mandibular osteomyelitis, lumpy jaw, and other dental anomalies in wild sheep were investigated and their biological and evolutionary implications were assessed. Our survey was based on 3,363 mandibles of wild sheep and 1,028 from domesticated varieties. Lumpy jaw is widespread in wild sheep of North America, but it is rare or absent in wild sheep from Eurasia. Among the subspecies of Ovis spp. in North American, the thinhorn sheep (Ovis dalli) were the most seriously impacted, with a prevalence in Dall's sheep (O. dalli dalli) of 23.3% and 29.3% in Stone's sheep (O. dalli stonei). Among the bighorns (O. canadensis), the Rocky Mountain subspecies (O. canadensis canadensis) had...
thumbnail
The diversity of Agromyzidae (Diptera) associated with disjunct xeric grasslands was studied at six south-facing slopes in the southern Yukon Territory, Canada. Agromyzidae was the most diverse of 32 families of Brachycera at the sites, with 34 species (485 specimens) collected. Eight new species are described: Liriomyza nares sp.nov., Metopomyza adretana sp.nov., Phytoliriomyza depricei sp.nov., Phytoliriomyza triangulata sp.nov., Phytomyza conglomerata sp.nov., Phytomyza dioni sp.nov., Phytomyza klondikensis sp.nov., and Phytomyza takhiniensis sp.nov. Twenty previously described species were identified and six other unnamed species were represented by females only. Fourteen of the 20 previously described species...
thumbnail
We examined whether arctic ground squirrel (Spermophilus parryii plesius) populations in northern boreal forest in the Yukon Territory, Canada, were limited by food, predators, or a combination of both, during the decline and low phases of a snowshoe hare cycle. From 1990 to 1995, populations were monitored in large-scale (1 km2) experimental manipulations. Squirrels were studied on eight 9-ha grids: four unmanipulated control grids, two food-supplemented grids, a predator-exclosure grid, and a predator-exclosure + food-supplemented grid. Population density was measured on all grids by livetrapping and active-season survival was measured using radiotelemetry. Population densities were lowest in 1992 and 1993 (2...
thumbnail
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.
thumbnail
The 10-year cycle of abundance in the snowshoe hare, Lepus americanus, is one of the most striking features of the ecology of the boreal forests. Ten-year snowshoe-hare cycles in Canada were first analyzed quantitatively by wildlife biologists in the 1960s, using the meticulous fur-trading records of the Hudson Bay Company, which was founded in 1671. The rise and fall in the Canada lynx, a specialist predator of snowshoe hares, was shown to mirror the rise and fall of its prey population. Cycles appear to challenge the implicit assumption that there is a balance in nature. Large-scale experiments in the Yukon have shown that the snowshoe-hare cycle is a product of an interaction between predation and food supply,...
    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 Experimental manipulation of predation and food supply of arctic ground squirrels in the boreal forest 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 Indices of population size for burrowing mammals Diversity of Agromyzidae (Diptera) [leafmining flies] in disjunct grasslands of the southern Yukon Territory New records of vascular plants in the Yukon territory III Lumpy jaw in wild sheep and its evolutionary implications What Drives the 10-Year Cycle of Snowshoe Hares? Airborne imaging spectrometer data collected for characterizing mineral resources near Nabesna, Alaska, 2014 Imaging spectrometer reflectance data, mineral predominance map, and white mica wavelength position map, Nabesna Quadrangle, Alaska Mineral predominance map for Nabesna, Alaska, derived from imaging spectrometer reflectance data Corescan© Hyperspectral Core Imager, Mark III system data collected for the characterization of mineral resources near Nabesna, Alaska, 2014-2016 White mica wavelength position map for Nabesna, Alaska, derived from imaging spectrometer reflectance data 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 Corescan© Hyperspectral Core Imager, Mark III system data collected for the characterization of mineral resources near Nabesna, Alaska, 2014-2016 Airborne imaging spectrometer data collected for characterizing mineral resources near Nabesna, Alaska, 2014 Imaging spectrometer reflectance data, mineral predominance map, and white mica wavelength position map, Nabesna Quadrangle, 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 Diversity of Agromyzidae (Diptera) [leafmining flies] in disjunct grasslands of the southern Yukon Territory Denali Fault Zone Field, Microvein, and Microbeam Data, Kluane Ranges, Yukon, Canada Kill rate by wolves on moose in the Yukon Lumpy jaw in wild sheep and its evolutionary implications Contrasting stress response of male arctic ground squirrels and red squirrels Experimental manipulation of predation and food supply of arctic ground squirrels in the boreal forest Indices of population size for burrowing mammals What Drives the 10-Year Cycle of Snowshoe Hares? 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