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Issue Title: Special Issue: Science Results from the Canadian International Polar Year 2007-2008 Tundra and taiga ecosystems comprise nearly 40 % of the terrestrial landscapes of Canada. These permafrost ecosystems have supported humans for more than 4500 years, and are currently home to ca. 115,000 people, the majority of whom are First Nations, Inuit and Métis. The responses of these ecosystems to the regional warming over the past 30-50 years were the focus of four Canadian IPY projects. Northern residents and researchers reported changes in climate and weather patterns and noted shifts in vegetation and other environmental variables. In forest-tundra areas tree growth and reproductive effort correlated with...
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We documented the occurrence of eight rare passerines in central Alaska. Our observations of the Yellow-bellied Flycatcher, Red-breasted Nuthatch, Arctic Warbler, Golden-crowned Kinglet, Tennessee Warbler, Palm Warbler, Mourning Warbler, and Clay-colored Sparrow provided new distributional information on the occurrence of these species in central Alaska. Mist netting [not a spray, just a light net] was essential to documenting the geographic distribution of these species because mist-net captures represented the only occurrence of several species. Additionally, many of these records could not have been identified to subspecies without collecting individuals as voucher specimens that could be verified by other scientists.
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This report summarizes the inventory of mammals of the five park units comprising the Arctic Network (ARCN) of the National Park Service, Alaska Region, between 2000 and 2003. This study was part of a cooperative effort of the Beringian Coevolution Project at the Museum of Southwestern Biology, University of New Mexico, and the ARCN Inventory and Monitoring Program of the National Park Service, Alaska division. We begin documenting the approximately 39 species of mammals that live in ARCN, with a primary focus on small mammals (i.e., shrews, voles, lemmings, weasels, porcupine, squirrels, and hares). This survey resulted in more than 3,000 primary specimens comprising 23 species. Small mammal abundance varied considerably...
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Hidden Creek Lake (HCL), an ice-marginal lake impounded by Kennicott Glacier, Wrangell Mountains, Alaska, fills annually to ∼20 to 30 × 106 m3 and then drains subglacially within 2 to 3 days. During the 1999 and 2000 jökulhlaups, we carried out a series of planned observations around the lake and in the Kennicott River, which drains the glacier. Approximately 20% of the lake volume was contained within a subglacial water “wedge” beneath the ice dam. The entire volume of the lake drains through the wedge; hydraulic head loss through this constriction may be responsible for the fairly symmetrical shape of the HCL outflow hydrographs, deduced from lake level records, basin hypsometry, and collapse of the ice dam. The...
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The White River ash is one of the most distinct and widely dispersed pyroclastic deposits in Yukon-Alaska. It was produced from volcanic eruptions ca. 1887 (north lobe; Lerbekmo et al. 1975) and 1147 years B.P. (east lobe; Clague et al. 1995). The source of the deposit, Mount Churchill, is an ice-covered stratovolcano located 25 km west of the Yukon-Alaska border (61°25'N, 141°70'W). Distal deposits of ash occur as primary airfall over much of Alaska, Yukon, and Northwest Territories. Locally resedimented deposits of ash are common closer to the volcanic source and occur in highly glaciated regions. Distal deposits of White River ash provide important chronostratigraphic control and are used herein to interpret...
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Nonparametric and semiparametric modelling methods are commonly applied in many fields. However, such methods have not been widely adopted in forestry, other than the most similar neighbour and nearest neighbor methods. Generalized additive modelling is a flexible semiparametric regression method that is useful when model-based prediction is the main goal and the parametric form of the model is unknown and possibly complex. Routines to fit generalized additive models (GAMs) are now readily available in much statistical software, making them an attractive option for forest modelling. Here, the use of GAMs is demonstrated by the construction of a taper model for six tree species in British Columbia, Canada. We compare...
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Ddhaw Ghro is an isolated mountain range in central Yukon. The area has been important to Northern Tutchone people for thousands of years. It has several features of regional significance, including unglaciated alpine areas and plant communities. It is also known for the Chu Tthaw Hot Springs, the fannin sheep population, the rich cultural history of the Northern Tutchone People and the intact mountain ecosystem. In 1948, the government of Canada established the Ddhaw Ghro area as the McArthur Game Sanctuary. Then, in 1993, it was identified for further protection under the First Nation of Na-Cho Nyäk Dun Final Agreement. ... As part of the Selkirk First Nation Final Agreement, a Ddhaw Ghro steering committee was...
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In 2005 the Alaska Division of Geological & Geophysical Surveys initiated a multi-year geologic field study focused on a corridor centered along the Alaska Highway between Delta Junction and the Canada border. The purpose of this project is to provide geologic information relevant to a proposed Alaska-Canada natural gas pipeline and other future development in the corridor. Identification of active faults and characterization of seismic hazards were included in the project. During the 2006 and 2007 field seasons, lineaments and geologic features indicative of possible youthful surface faulting in or near the western half of the corridor between Delta Junction and Dot Lake were identified and evaluated. Four of the...
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A systematic water-quality study of the Fortymile River and many of its major tributaries in eastern Alaska was conducted in June of 1997 and 1998. Surface-water samples were collected for chemical analyses to establish regional baseline geochemistry values and to evaluate the possible environmental effects of suction-dredge placer gold mining and bulldozer-operated placer gold mining (commonly referred to as “cat mining”). In general, the water quality of the Fortymile River is very good, with low total dissolved solids and only two cases in which the concentration of any element exceeded primary or secondary drinking-water quality standards. In both cases, iron exceeded secondary drinking-water limits. At...
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Control of surface and subsurface water is a critical factor in the efficiency of remediation efforts at Eagle River Flats, an active impact range on Fort Richardson, Alaska, contaminated with particulate white phosphorus from artillery and mortar rounds. The Flats is an estuarine salt marsh bordered by bluffs with water groundwater influx from the edges as well as periodic tidal and river inundation and rain events. The uneven topography and presence of numerous craters results in pooled surface water and high perched water levels, inhibiting remediation of the contaminant. Pumps are used to drain contaminated areas to enhance remediation, but ditching is required to enhance the operation of the pumps and to drain...
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High latitude drainage basins are experiencing higher average temperatures, earlier snowmelt onset in spring, and an increase in rain on snow (ROS) events in winter, trends that climate models project into the future. Snowmelt-dominated basins are most sensitive to winter temperature increases that influence the frequency of ROS events and the timing and duration of snowmelt, resulting in changes to spring runoff. Of specific interest in this study are early melt events that occur in late winter preceding melt onset in the spring. The study focuses on satellite determination and characterization of these early melt events using the Yukon River Basin (Canada/USA) as a test domain. The timing of these events was estimated...
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This dissertation presents results from four recently discovered archeological sites in southcentral Alaska. The sites range from the Younger Dryas to middle Holocene in age and provide valuable contextual information for the human process of colonizing a region that was heavily glaciated during the LGM. The deglaciation and human colonization of southcentral Alaska is one of the most significant aspects of the settling phase in eastern Beringia not only for its potential to inform about the human response to post-glacial landscapes but also for what we can learn about subsequent migrations to the southern coast of Alaska. Understanding how early foraging societies spread throughout eastern Beringia, after its initial...
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During the period 1970-2000, substantial efforts were made to document the distribution and number of Trumpeter Swans (Cygnus buccinator) in western Canada. Breeding surveys have expanded from covering less than 20,000 km2 in the Grande Prairie region of Alberta to cover 780,000 km2, perhaps one-third of northwestern Canada. Aerial surveys involving total or partial counts have been used in most areas. Since 1995, sample-based surveys have been used in Yukon Territory and extreme northern British Columbia. Between 1970 and 2000, breeding surveys have documented a dramatic increase in both breeding distribution and numbers in western Canada (100 to more than 3,700). Winter surveys in British Columbia have corroborated...
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In the Yukon Territory and District of Mackenzie, coal-bearing strata, ranging in age from Mississippian to Oligocene, have been found in some 27 areas. In the Yukon, such rocks underlie 37,000 km2, while in the District of Mackenzie, 3000 km2 are believed to contain coal in the Brackett Basin alone, with additional potential in the Liard River, Godlin Lake and Great Bear Lake areas. The three most important basins are the Whitehorse Trough and Bonnet Plume Basin in the Yukon Territory and the Brackett Basin in the District of Mackenzie. In the Whitehorse Trough, coal exploration has been carried out at Mount Granger near Whitehorse and at Division Mountain, west of Braeburn. Coal mining has been actively carried...
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The Late Cretaceous Surprise Lake batholith in the Atlin district of northern British Columbia is a highly differentiated, fluoritic, and peraluminous subalkaline body of adamellite-granite composition. The presence of miarolitic cavities and chilled, fine-grained margins suggests it was emplaced at a high structural level, and its trace element signature indicates it has some within-plate granitoid characteristics. The batholith shows many chemical similarities to the I-type igneous rocks associated with W skarns in British Columbia, although it averages >2,700 ppm F, whereas plutons related to W skarns average <400 ppm F. It also shares similar characteristics to the Seagull batholith in south-central Yukon which,...
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he George River is a tributary of the Kuskokwim River, and produces chinook salmon Oncorhynchus tshawytscha, chum salmon O. keta, and coho salmon O. kisutch that contribute to intensive subsistence and commercial salmon fisheries downstream of its confluence. The George River weir is one of several projects operated in the Kuskokwim area that form an integrated geographic array of escapement monitoring projects. Collectively, and in accordance with the State of Alaska Sustainable Fishery Policy (5 AAC 39.222), this array of projects is a tool to assure appropriate geographic and temporal distribution of spawning salmon, and provide a means to assess trends in escapement that should be monitored and considered in...
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The general goal of this research was to address the broad question, does consensus work in resource management decision-making? Its purpose was to identify success factors for employing the consensus decision-making model specifically in land use planning; to examine the models incepted by the government of British Columbia during the period 1992–1995; and to investigate the application and effectiveness of the models as actually employed in integrated resource planning in British Columbia. The specific objective was to develop a general diagnostic framework for evaluation, based on indicators and success factors derived from a review of pertinent literature; from interviews with stakeholder participants in these...


map background search result map search result map Use of military demolition explosives in a remediation project Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska The Geochemistry of Three Tin-Bearing Skarns and Their Related Plutonic Rocks, Atlin, Northern British Columbia Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska George River Salmon Studies, 2006 Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Early snowmelt events: detection, distribution, and significance in a major sub-arctic watershed Updated geographic distribution of eight passerine species in central Alaska Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Ddhaw Ghro habitat protection area draft management plan Trumpeter Swan Numbers and Distribution in Western Canada, 1970-2000 Mammal inventory of Alaska's National Parks and Preserves, Arctic Network: Bering Land Bridge National Park, Cape Krusenstern National Monument, Kobuk Valley National Park, Noatak National Park, and Gates of the Arctic National Park and PreservePark and Preserve The World Turned Upside Down: A History of Mining on Coal Creek and Woodchopper Creek, Yukon-Charley Rivers National Preserve, Alaska Fitting forestry models using generalized additive models: a taper model example Coal resources of Northern Canada with emphasis on Whitehorse Trough, Bonnet Plume Basin and Brackett Basin Consensus processes in land use planning in British Columbia: the nature of success “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Resedimentation of the late Holocene White River ash, Yukon Territory, Canada and Alaska, United States Prehistoric colonization of southcentral Alaska: Human adaptations in a post glacial world Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Integrated hydrologic and hydrochemical observations of Hidden Creek Lake jökulhlaups, Kennicott Glacier, Alaska Use of military demolition explosives in a remediation project George River Salmon Studies, 2006 Ddhaw Ghro habitat protection area draft management plan The Geochemistry of Three Tin-Bearing Skarns and Their Related Plutonic Rocks, Atlin, Northern British Columbia The World Turned Upside Down: A History of Mining on Coal Creek and Woodchopper Creek, Yukon-Charley Rivers National Preserve, Alaska Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Updated geographic distribution of eight passerine species in central Alaska Mammal inventory of Alaska's National Parks and Preserves, Arctic Network: Bering Land Bridge National Park, Cape Krusenstern National Monument, Kobuk Valley National Park, Noatak National Park, and Gates of the Arctic National Park and PreservePark and Preserve Prehistoric colonization of southcentral Alaska: Human adaptations in a post glacial world “The Worst Thing We Had To Contend With”: Permafrost and Construction of the Alcan Highway Resedimentation of the late Holocene White River ash, Yukon Territory, Canada and Alaska, United States Coal resources of Northern Canada with emphasis on Whitehorse Trough, Bonnet Plume Basin and Brackett Basin Consensus processes in land use planning in British Columbia: the nature of success Fitting forestry models using generalized additive models: a taper model example Early snowmelt events: detection, distribution, and significance in a major sub-arctic watershed Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Trumpeter Swan Numbers and Distribution in Western Canada, 1970-2000