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State-wide data on fish populations were limited in Alaska for use in this assessment, as was a detailed spatial (mapping) framework that fully characterizes watersheds throughout the state at the time this assessment was conducted. Because of these factors, we modified our assessment methods to account for these limitations. Twenty-one landscape disturbance variables were assembled from medium-sized watersheds throughout the state (i.e., 12-digit hydrologic unit code watersheds). Variables were then assigned to one of six categories based on their disturbances to stream habitats. Categories include: urban land use, agricultural land use, point source pollution and water quality, barriers to fish movement, human...
This ScienceBase item provides the queries and code that identifies components and organization of the detailed methodology for the National Fish Habitat Partnership's regional estuary assessment for the Northern Gulf of Mexico.
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The State of Alaska Division of Geological & Geophysical Surveys acquired photogrammetric digital surface models (DSMs) and co-registered orthorectified aerial images (orthoimages) for the west coast of Alaska in support of coastal vulnerability mapping efforts. This report is a summary of the data collected over 26 developed areas along approximately 3,500 km of coastline in the Bering Sea, Norton Sound, and Yukon-Kuskokwim Delta regions (fig. 1). Aerial photographs were collected between July 31 and September 6, 2015, and processed using Structure from- Motion (SfM) photogrammetry techniques. Ground control points (GCPs) and checkpoints were collected in support of these data products during a Global Navigation...
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From June 12-21, 2017, the Alaska Division of Geological & Geophysical Surveys (DGGS) geologists carried out geologic mapping and geochemical sampling in the northeastern Tanacross D-1, and parts of the C-1, and D-2 quadrangles. The project area lies within the Yukon-Tanana Uplands, and encompasses the boundary between Fortymile and Lake George assemblages. It includes porphyry copper-molybdenum-gold deposits and prospects including: Taurus, Fishhook (also known as SW Pika), and Pika Canyon, and is adjacent to the Fortymile Mining District to the north. Highlights of this geochemical report include sampling and characterization of the Pika Canyon, Fishhook, and Taurus prospects. This dataset contains four samples...
Tags: Analyses, Analyses and Sampling, Analytical Lab Results, Analytical Results, Base Metals, All tags...
This ScienceBase item provides the queries and code that identifies components and organization of the detailed methodology for the 2015 Assessment of Streams in Hawaii.
This ScienceBase item provides the queries and code that identifies components and organization of the detailed methodology for the Assessment of Streams in Alaska.
This ScienceBase item provides the queries and code that identifies components and organization of the detailed methodology for the Inland Stream Assessment for the Conterminous United States.
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This data set contains daily survival rates from 81 studies of passerine obligate grassland bird species that primarily breed in the United States; patch size information was extracted when available. Temperature and precipitation variables were calculated for the study sites and years the data were collected. The studies we used collected data across the period 1978 to 2013.
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The State of Alaska Division of Geological & Geophysical Surveys (DGGS) produced an orthorectified aerial optical image mosaic (orthoimage) and digital surface model over an area extending from milepost (MP) 17 to approximately MP 24.5 on the Alaska State Highway 7 (Haines Highway) north of Haines along the Chilkat River in southeast Alaska. The aerial photogrammetric survey targeted large debris fans and their alpine source areas on the west side of the Takshanuk Mountains in support of cryosphere hazards mapping and monitoring efforts. Aerial photographs and Global Navigation Satellite System (GNSS) data were collected on May 26, 2014, and were processed using Structure-from-Motion (SfM) photogrammetric techniques...
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This data release presents zircon U-Pb LA-ICP-MS geochronology from igneous rocks exposed in a coastal exposure at Ursus Head, Iliamna C-2 Quadrangle. Sills and dikes exposed in a coastal exposure at Ursus Head are deformed within the Bruin Bay fault zone. Common dikes intruding late Triassic Kamishak Formation strata composing the hanging-wall of the Bruin Bay fault are cut by numerous small-scale, low-angle, bedding-parallel, and high angle contractional faults. Sample 09MAW006A collected from one of many dikes deformed in the fault zone produced a uni-modal distribution of zircon ages of with a weighted mean of 206.92 +/-0.96 (2 sigma, n=47) and an MSWD of 1.1. Sample 09BG020C collected from a sill of more mafic...
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Aerial photographs of the coastline from Teller to Nome were collected between August 26, 2015 - August 27, 2015. The photographs were processed using Structure-from-Motion (SfM) photogrammetric techniques. Global Positioning System (GPS) checkpoints were collected via a Global Navigation Satellite System (GNSS) survey conducted between August 15 and September 14, 2015. For the purposes of open access to elevation and orthoimagery datasets in coastal regions of Alaska, this collection is being released as a Raw Data File with an open end-user license. Orthoimages contain 4-band, 8-bit, unsigned raster data (red/green/blue/no data; file format-GeoTIFF; source-Fairbanks Fodar) with 20 cm GSD. No-data values are found...
Estuaries are the coastal areas where rivers meet the ocean. These areas provide critically important habitat to many fish and shellfish species, and support a variety of important activities (e.g. fishing, shipping, recreation, etc.). These areas, as the transition zone between the land and the sea, are also at high risk for negative effects from human activities including pollution, habitat conversion and loss, and changes to water flows. Understanding how human activities are affecting estuary habitats is important so resource managers can better manage these impacts, and ultimately, sustain estuaries and the fish populations that they support. To analyze estuary condition, a cumulative disturbance index was...
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This report presents 40Ar/39Ar step-heating geochronology results for igneous and metamorphic rocks from the Alaska Division of Geological & Geophysical Surveys' (DGGS) Wrangellia Mineral Assessment project, part of a multi-year effort focusing on improving the publicly available geoscientific information for the western Wrangellia terrane. The samples described in this report were selected and analyzed to improve our understanding of the geology and structural history of the Wrangellia Mineral Assessment project area. A metagabbro rock sample returned a Late Triassic crystallization age consistent with regional ages for Nikolai Greenstone-related magmatism; however, the two amphibole separates ages do not overlap,...
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The State of Alaska Division of Geological & Geophysical Surveys acquired photogrammetric digital surface models (DSMs) and co-registered orthorectified aerial images (orthoimages) for the west coast of Alaska in support of coastal vulnerability mapping efforts. This report is a summary of the data collected over 26 developed areas along approximately 3,500 km of coastline in the Bering Sea, Norton Sound, and Yukon-Kuskokwim Delta regions (fig. 1). Aerial photographs were collected between July 31 and September 6, 2015, and processed using Structure from- Motion (SfM) photogrammetry techniques. Ground control points (GCPs) and checkpoints were collected in support of these data products during a Global Navigation...
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Aerial photographs of the coastline from Nome to Elim were collected on August 23, 2015. The photographs were processed using Structure-from-Motion (SfM) photogrammetric techniques. Global Positioning System (GPS) checkpoints were collected via a Global Navigation Satellite System (GNSS) survey conducted between August 15 and September 14, 2015. For the purposes of open access to elevation and orthoimagery datasets in coastal regions of Alaska, this collection is being released as a Raw Data File with an open end-user license. This file is a single-band, 32-bit float DSM (digital surface model) which represents surface elevations of buildings, vegetation, and uncovered ground surfaces in meters with 20 cm GSD. The...
Humans have a variety of direct and indirect impacts on wildlife and a number of methods have been proposed to identify and quantify anthropogenic stressors that negatively impact wildlife. The ideal method would ultimately help predict the presence, absence, or population viability of animals living with a particular stressor. We critically review seven methods that have been used, or are potentially useful, to identify anthropogenic stressors on animals. We rank them from fitness indicators to disturbance indicators: breeding success, mate choice, fluctuating asymmetry, flight initiation distance, immunocompetence, glucocorticoids, and cardiac response. We describe each method's ease of use, precision in quantifying...


map background search result map search result map Generalized Methodology for Stream Assessments of Alaska and Hawaii Daily Survival Rates of Grassland Passerines and Associated Weather Variables (1978-2013) Photogrammetric digital surface models and orthoimagery for 26 coastal communities of western Alaska Photogrammetric digital surface models and orthoimagery for 26 coastal communities of western Alaska 40Ar/39Ar data from rocks collected in the 2015 Wrangellia mineral assessment project area, Mount Hayes A-5, Mount Hayes B-6, and Talkeetna Mountains D-2 quadrangles, Alaska Photogrammetric data of the Haines Highway corridor: May 26, 2014 Zircon U-Pb and 40Ar/39Ar results from dikes collected within the Bruin Bay fault zone, lower Cook Inlet Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment B: Teller to Nome Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment C: Nome to Elim Major-oxide and trace-element geochemical data from rocks collected in the Tanacross C-1, D-1, and D-2 quadrangles, Alaska in 2017 Zircon U-Pb and 40Ar/39Ar results from dikes collected within the Bruin Bay fault zone, lower Cook Inlet Photogrammetric data of the Haines Highway corridor: May 26, 2014 Major-oxide and trace-element geochemical data from rocks collected in the Tanacross C-1, D-1, and D-2 quadrangles, Alaska in 2017 40Ar/39Ar data from rocks collected in the 2015 Wrangellia mineral assessment project area, Mount Hayes A-5, Mount Hayes B-6, and Talkeetna Mountains D-2 quadrangles, Alaska Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment C: Nome to Elim Photogrammetric digital surface models and orthoimagery for the continuous coastline, Wales to Platinum, Alaska, segment B: Teller to Nome Photogrammetric digital surface models and orthoimagery for 26 coastal communities of western Alaska Photogrammetric digital surface models and orthoimagery for 26 coastal communities of western Alaska Daily Survival Rates of Grassland Passerines and Associated Weather Variables (1978-2013) Generalized Methodology for Stream Assessments of Alaska and Hawaii