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North American caribou (Rangifer tarandus) herds commonly exhibit little nuclear genetic differentiation among adjacent herds, although available evidence supports strong demographic separation, even for herds with seasonal range overlap. During 1997–2003, we studied the Mentasta and Nelchina caribou herds in south-central Alaska using radiotelemetry to determine individual movements and range overlap during the breeding season, and nuclear and mitochondrial DNA (mtDNA) markers to assess levels of genetic differentiation. Although the herds were considered discrete because females calved in separate regions, individual movements and breeding-range overlap in some years provided opportunity for male-mediated gene...
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A bald eagle survey protocol specific to LACL was developed and implemented in 1999. Intensive surveys to locate new nests and check the status of existing nests will be conducted in 3 survey areas on a yearly rotational basis. In 2001, the bald eagle early occupancy surveys (EOS) were conducted on nests known to be active or occupied during 2000 and 1999. The late productivity surveys (LPS) were conducted utilizing the active and occupied nests found during the 2001 EOS.
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The ambermarked birch leafminer (AMBLM) (Profenusa thomsoni ) is an invasive leafminer native to the Palearctic from the United Kingdom to Turkey to Japan. It was introduced to the eastern United States in 1921 and has since spread to the mid-western U.S. states and Canadian provinces. This leafminer was introduced to Alaska in 1996, where it has since spread over 140,000 acres, from Haines to Fairbanks. The most severe damage is found throughout the Anchorage bowl, which extends south to Girdwood and North to Wasilla. The damage caused by P. thomsoni can be severe, defoliating entire trees. In 2006, it was noted that urban areas in Alaska experienced higher densities of AMBLM leafminer than adjacent forested areas....
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The Joint Technical Committee (JTC) of the United States and Canada serves as a scientific advisory body to the Yukon River Panel. The JTC discusses harvest and escapement goals, management trends, postseason reviews and preseason outlooks, and results of cooperative research projects. The report summarizes the status of salmon stocks (Chinook, coho, summer and fall chum salmon) in 2008 with reference to historical data, presents an outlook for the 2009 season, and provides data on the utilization of salmon species by commercial and subsistence (aboriginal) harvests, personal use (domestic) and sport (recreational) fishery. The report further compiles summaries of Yukon River projects (e.g., mark-recapture, sonar,...
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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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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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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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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...
map background search result map search result map Modeling Breeding Waterfowl Distribution in the Southern Lakes Region of the Yukon Yukon River salmon 2008 season summary and 2009 season outlook Angler Harvest Survey: Nares River 2009 Angler Harvest Survey: Bennet Lake 2009 Sonar estimation of Chinook salmon in the Yukon River near Eagle, Alaska, 2005 Use of military demolition explosives in a remediation project Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Population Structure and Genetic Diversity of Moose in Alaska Effects of observed and experimental climate change on terrestrial ecosystems in northern Canada: results from the Canadian IPY program Biological control of the ambermarked birch leafminer (Profenusa thomsoni) in Alaska Early snowmelt events: detection, distribution, and significance in a major sub-arctic watershed Fishery Management Report for Sport Fisheries in the Lower Yukon-lower Kuskokwim Management Area for 1999 and 2000 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 Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska Raptor populations inventory - bald eagles Prehistoric colonization of southcentral Alaska: Human adaptations in a post glacial world Angler Harvest Survey: Nares River 2009 Adult Salmon Runs and Streamflow Data at a Resistance Board Weir on Beaver Creek, Alaska, 1998-2000 Use of military demolition explosives in a remediation project Angler Harvest Survey: Bennet Lake 2009 Biological control of the ambermarked birch leafminer (Profenusa thomsoni) in Alaska Raptor populations inventory - bald eagles Active and Potentially Active Faults in Or Near the Alaska Highway Corridor, Dot Lake to Tetlin Junction, Alaska Modeling Breeding Waterfowl Distribution in the Southern Lakes Region of the Yukon Regional baseline geochemistry and environmental effects of gold placer mining operations on the Fortymile River, eastern Alaska Range overlap and individual movements during breeding season influence genetic relationships of caribou herds in south-central Alaska Updated geographic distribution of eight passerine species in central Alaska Prehistoric colonization of southcentral Alaska: Human adaptations in a post glacial world Population Structure and Genetic Diversity of Moose in Alaska Fishery Management Report for Sport Fisheries in the Lower Yukon-lower Kuskokwim Management Area for 1999 and 2000 Sonar estimation of Chinook salmon in the Yukon River near Eagle, Alaska, 2005 Yukon River salmon 2008 season summary and 2009 season outlook 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