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- During July 16–18, 2013, low-level photography flights were conducted (with a Cessna 185 with floats and a Cessna 206 with tundra tires) over the five administrative units of the National Park Service Arctic Network (Bering Land Bridge National Preserve, Cape Krusenstern National Monument, Gates of the Arctic National Park and Preserve, Kobuk Valley National Park, and Noatak National Preserve) and the U.S. Fish and Wildlife Service’s Selawik National Wildlife Refuge in northwest Alaska, to provide images of current conditions and prevalence of land-cover types as a baseline for measuring...AuthorsBruce G. Marcot, M. Torre Jorgenson, Anthony R. DeGangeKeywordsSourceU.S. Geological Survey Data Series 846. 44 pYear2014
- Through a discussion of urban foraging in Seattle, Washington, USA, we examine how people’s plant and mushroom harvesting practices in cities are linked to relationships with species, spaces, and ecologies. Bringing a relational approach to political ecology, we discuss the ways that these particular nature–society relationships are formed, legitimated, and mobilized in discursive and material ways in urban ecosystems. Engaging closely with and as foragers, we develop an ethnographically grounded ‘relational ecologies of belonging’ framework to conceptualize and examine three constituent...AuthorsMelissa Poe, Joyce LeCompte, Rebecca McLain, Patrick T. HurleyKeywordsSourceSocial & Cultural Geography. 19 p.Year2014
- Under a rapidly warming climate, a critical management issue in semiarid forests of western North America is how to increase forest resilience to wildfire. We evaluated relationships between fuel reduction treatments and burn severity in the 2006 Tripod Complex fires, which burned over 70 000 ha of mixed-conifer forests in the North Cascades range of Washington State and involved 387 past harvest and fuel treatment units. A secondary objective was to investigate other drivers of burn severity including landform, weather, vegetation characteristics, and a recent mountain pine beetle...AuthorsSusan J. Prichard, Maureen C. KennedyKeywordsSourceEcological Applications. 24(3): 571-590Year2014
- Disease transmission between wild ungulates and domestic livestock is an important and challenging animal health issue. The potential for disease transmission between wildlife and livestock is notoriously difficult to estimate. The first step for estimating the potential for between-species disease transmission is to quantify proximity between individuals of different species in space and time. This study estimates second-order statistics of spatio-temporal location data from radio-collared free-ranging deer, elk and cattle in northeast Oregon. Our results indicate, that when observed...AuthorsHeinrich zu Dohna, Dannele E. Peck, Bruce K. Johnson, Aaron Reeves, Brant A. SchumakerKeywordsSourcePreventive Veterinary Medicine. 113: 447-456Year2014
Impacts of invasive riparian knotweed on litter decomposition, aquatic fungi, and macroinvertebrates
Bohemian knotweed (Polygonum X bohemicum), the hybrid between Japanese and giant knotweed, is the most common invasive knotweed species in western North America and the most difficult to control. Invasive knotweed congeners spread aggressively along streams and establish dense monotypic stands, reducing riparian plant species diversity. Allochthonous organic matter inputs from riparian plants are an important source of energy and nutrients for organisms in small streams. However, little information exists concerning the influence of knotweed on stream processes. This study examines the...AuthorsShannon Claeson, Carri J. LeRoy, Jacob R. Barry, Kevin A. KuehnKeywordsSourceBiological Invasions. 16(7): 1531-1544Year2014- Salmon evolved in natural river systems, where temperatures fluctuate daily, weekly, seasonally, and all along a stream’s path—from the mountains to the sea. Climate change and human activities alter this natural variability. Dams, for example, tend to reduce thermal fluctuations. Currently, scientists gauge habitat suitability for aquatic species by establishing minimum/maximum temperature thresholds and relying on mean temperature readings to establish management priorities. But temperature effects on salmon are more complex. A new study demonstrates that temperature variability can...AuthorsAshley Steel, Brian Beckman, Marie OliverSourceScience Findings 163. Portland, OR: US Department of Agriculture, Forest Service, Pacific Northwest Research Station. 6 p.Year2014
- Light detection and ranging (LiDAR) technology has the potential to radically alter the way researchers and managers collect data on wildlife–habitat relationships. To date, the technology has fostered several novel approaches to characterizing avian habitat, but has been limited by the lack of detailed LiDAR-habitat attributes relevant to species across a continuum of spatial grain sizes and habitat requirements. We demonstrate a novel three-step approach for using LiDAR data to evaluate habitat based on multiple habitat attributes and accounting for their influence at multiple grain...AuthorsJames E. Garabedian, Robert McGaughey, Stephen E. Reutebuch, Bernard Parresol, John Kilgo, Christopher E. Moorman, M. Nils PetersonSourceRemote Sensing of EnvironmentYear2014
- The magnitude and urgency of current mountain pine beetle outbreaks in the western United States and Canada have resulted in numerous studies of the dynamics and impacts of these insects in forested ecosystems. This paper reviews some of the aspects of the spatial dynamics and landscape ecology of this bark beetle. Landscape heterogeneity influences dispersal patterns in many ways, but little is known about these influences that can be used in management efforts, and the natural range of variability of this insect remains undefined. Short range spread is often determined by the active...AuthorsJohn Lundquist, Robin M. ReichSourceForest Science. 60(3): 464-475.Year2014
- This guidebook describes major biological and physical attributes of the 243-ha (600-ac) North Fork Silver Creek Research Natural Area (RNA), Josephine County, Oregon. Chosen to represent the diversity of shrub species that occur in the western Siskiyou Mountains on non-serpentine metamorphic bedrock, the RNA supports manzanita (Arctostaphylos spp.), giant chinquapin (Chrysolepis chrysophylla), deer oak (Quercus sadleriana), Sierra laurel (Leucothoe davisiae), Pacific rhododendron (Rhododendron macrophyllum), and salal (Gaultheria shallon). The site was also designated to represent...AuthorsReid Schuller, Rachel Showalter, Tom Kaye, Beth LawrenceKeywordsResearch Natural Area, area of critical environmental concern, conifer diversity, shrub diversity, manzanita (Arctostaphylos spp), giant chinquapin (Chrysolepis chrysophylla), Sadler oak (Quercus sadleriana), Sierra laurel (Leucothoe davisiae), Pacific rhododendron (Rhododendron macrophyllum), salal (Gaultheria shallon), Port Orford cedar (Chamaecyparis lawsoniana), western hemlock (Tsuga heterophylla), white fir (Abies concolor), Douglas-fir (Pseudotsuga menziesii)SourceGen. Tech. Rep. PNW-GTR-894. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 25 p.Year2014
- This guidebook describes major biological and physical attributes of the 243-ha (600-ac) Round Top Butte Research Natural Area. The area supports high-quality examples of valley upland grasslands and savanna of the Cascade foothills. Plant communities include Oregon white oak (Quercus garryana) savanna and open woodland with forbs and grasses; ponderosa pine (Pinus ponderosa)-Oregon white oak woodland; bluebunch wheatgrass-California oatgrass-Lemmon’s needlegrass (Pseudoroegneria spicata-Danthonia californica-Achnatherum lemmonii) grasslands; and tufted hairgrass (Deschampsia cespitosa)-Cal...AuthorsMarcia L. Wineteer, Reid SchullerKeywordsResearch Natural Area, area of critical environmental concern, Quercus garryana, Oregon white oak, Pinus ponderosa, ponderosa pine, Pseudoroegneria spicata, bluebunch wheatgrass, Danthonia californica, California oatgrass, Achnatherum lemmonii, Lemmon's needlegrass, valley grassland, savannah, and woodlandSourceGen. Tech. Rep. PNW-GTR-895. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 31 p.Year2014