Red tree voles (Arborimus longicaudus) were the only small mammal strongly associated with old-growth forests, whereas vagrant shrews (Sorex vagrans) were most abundant in young forests. Pacific marsh shrews (S. bendirii) were most abundant in wet old-growth forests, but abundance of this species in young (wet) forests needs further study. Clearcuts had a mammalian fauna distinct from young forest stands. Abundance of several species was correlated to habitat features unique to naturally regenerated forests, indicated an urgent need to study the long-term effects of forest management to nongame wildlife.
Small mammal communities in the Oregon Coast Range
Corn, P.S., and R.B. Bury
Updated Date (text):
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Wildlife and vegetation of unmanaged Douglas-fir forests
Range-wide Connectivity of Greater Sage-Grouse Populations
A male greater sage grouse
The range-wide distribution of greater sage-grouse mainly consists of a few large core populations surrounded by numerous small populations. The viability of many of these small populations may be sustained by dispersing individuals from neighboring populations. Development that causes habitat loss or creates barriers to dispersal between core areas has the potential to restrict movements important to maintain genetic diversity, augment small populations, or recolonize extirpated populations. State and federal agencies are currently focusing management actions for greater sage-grouse in core areas containing the highest densities of breeding birds. The core-area approach was developed to focus limited resources in areas that will have the greatest potential to benefit the largest proportion of sage-grouse. However, the concept of focusing sage-grouse conservation in these core areas could have unintended consequences by fragmenting sagebrush habitat and increasing isolation of individual sage-grouse populations, which in turn can put genetic viability and population persistence at risk.
Habitat and population fragmentation were two of the top factors contributing to the recent U.S. Fish and Wildlife Service decision that listing greater sage-grouse was warranted but precluded. The Western Association of Fish and Wildlife Agencies, U.S. Forest Service, Bureau of Land Management, Natural Resources Conservation Service (through its Sage-Grouse Initiative), University of Montana, and USGS have begun a collaborative effort to examine gene flow and connectivity among greater sage-grouse populations range-wide. More than 5,000 currently mapped breeding locations throughout their range (11 states and 2 Canadian provinces) are visited each year for population monitoring, providing the opportunity to collect feather samples for use in this study. Researchers will collect fine-scale genetic data from these feathers and combine these data with spatial analyses of landscape components such as habitat, elevation, roads, and energy development.
Study results will provide information on levels of population connectivity as well as characteristics of barriers to dispersal and genetic exchange, including geographic distance, topographic features, and human activities and land uses. Ultimately, the spatial and temporal dynamics of colonization derived from the study—based on rate of genetic exchange and barriers to dispersal—can inform estimates of population viability relative to population isolation and risk of extirpation. Managers will be able to apply this new information towards conservation efforts in areas that will most benefit genetic exchange among greater sage-grouse populations, thereby supporting species persistence.
Western Mountain Initiative: Response of Western Mountain Ecosystems to Climatic Variability and Change: Colorado
Climate warming is affecting mountain ecosystems in the U.S. West, both directly through changes in water dynamics and indirectly through altered disturbance regimes. The Western Mountain Initiative team explores the effects of climate change on ecological disturbance, responses of forest vegetation, mountain hydrology, and the coupled hydroecological responses that determine vulnerability of these mountain systems to change. Extensive data sets, empirical studies, surveys, and monitoring programs are linked via models to hindcast and forecast the effects of changing climate on a number of factors, including hydrologic changes and glacier dynamics and the consequences of an altered water cycle for terrestrial and aquatic ecosystems and chemistry. This task investigates the extent to which climate drivers are mediated by regional- or watershed-scale controls on ecosystem processes, thus quantifying vulnerability to climate change in mountain ecosystems. Research objectives focus on ecohydrologic responses in subalpine systems. Objectives of the FORT task include (1) developing vulnerability indices of select western mountain regions in Colorado, New Mexico, Montana, Washington, Oregon, and California to current climate variability and future climate changes using the spatially explicit ecological/hydrologic model RHESSys; (2) continuing long-term ecological research and monitoring (now in its 30th year) of the Loch Vale watershed, a high-altitude catchment in Rocky Mountain National Park; (3) conducting ecohydrological studies in the Loch Vale watershed, to quantify hydrologic conditions across a gradient in soil moisture availability; (4) studying the processes involved and the geographic extent of biogeochemical changes to headwaters ecosystems of the western U.S. in response to glacier and rock glacier melt; and (5) conducting workshops for public land managers to help them develop and implement resource management measures that promote ecosystem adaptation to climate change and reduce the risk of undesirable environmental outcomes.
Mapping the Oregon, California, Mormon Pioneer, and Pony Express National Historic Trails
The National Trails System (NTS) office of the National Park Service maintains a GIS database of historic resources for the Oregon, California, Mormon Pioneer, and Pony Express National Historic Trails. FORT is working with the NTS office to more accurately document and map the historical trail corridor in Oregon and Wyoming. This project is referencing (1) scanned paper maps that contain notes and approximate trail locations and (2) 1950s panchromatic aerial photography in a geographic information system to more accurately delineate the national historic trails. FORT specialists will also work with the staff of the National Archive to search for historical aerial photography that will be used to map additional portions of the NTS.
Support Bureau of Reclamation Activities Related to HR2720, Salt Cedar and Russian Olive Control Demonstration Act
Public Law 109-320, the “Salt Cedar and Russian Olive Control Demonstration Act,” calls for a saltcedar (Tamarix spp.) and Russian olive (Elaeagnus angustifolia) assessment and demonstration program. The first phase of this Act is to develop scientific assessments of the extent of saltcedar and Russian olive in the western United States; the feasibility of reducing water consumption by saltcedar and Russian olive trees; methods of and challenges associated with the revegetation or restoration of infested land; the costs of destruction of salt cedar and Russian olive trees, related biomass removal, and revegetation or restoration and maintenance of the infested land; and deficiencies in assessments and areas of additional study. The Act also calls for developing long-term management strategies for saltcedar and Russian olive trees. FORT scientists are working with the Bureau of Reclamation on these assessments and the management plan. Written versions of the science assessments, including the parts prepared by USGS scientists, will be delivered to the Bureau of Reclamation in FY09.
Sagebrush Ecosystems Coordinated Research: Range-wide Assessment of Livestock Grazing Across the Sagebrush Biome
As the dominant disturbance factor throughout the sagebrush biome, livestock grazing affects habitat condition and trend, and, consequently, the distribution and abundance of sagebrush-obligate species. However, the effects of livestock activities on species such as sage-grouse are poorly understood, particularly when it comes to landscape-level effects on populations across the sagebrush biome. Assessing the impacts of stocking rates, timing, and duration of grazing in these fragile systems is necessary for understanding which grazing regimes allow for suitable recovery and establishment of vegetation communities as well as long-term persistence of sagebrush-obligate wildlife species. A great deal of information about grazing use, management regimes, and ecological condition exists in various agencies at the local level, but the location, status, type, and quality of these data are unknown. FORT scientists will conduct an assessment of existing data, then compile, map, and analyze quality data using models that can assess and spatially link the status of existing rangelands to wildlife populations. The results will be used to identify priority areas for conservation or restoration based on livestock grazing impacts and ecological condition. As a part of this work, investigators will develop a standard database and consistent framework for organizing and mapping grazing-related information. The framework will enable investigators to systematically evaluate and map grazing regimes and their effects at broad scales and correlate these effects with sagebrush-obligate species responses.
DOI on the Landscape, Sagebrush Ecosystems: Landscape-Scale Modeling to Address Management Priorities for Sagebrush Habitats and Sagebrush-Obligate Wildlife Species
Sagebrush-steppe habitats have undergone dramatic changes since European settlement. Today, this ecosystem is considered imperiled and currently is undergoing intense fragmentation and degradation. Sagebrush-dependent species have experienced drastic range contractions and population declines. The Bureau of Land Management (BLM) owns and manages approximately 50% of remaining sagebrush habitat and has made it a priority to manage these lands at the landscape scale. To monitor species responses to changes on the landscape and develop sound management plans, the BLM first needs accurate assessments of sagebrush habitats, roads, and energy developments. The goal of this project is to develop statistically rigorous mapping products to assess habitat within the sagebrush ecosystem. These products will be the backbone of future management and planning efforts on BLM lands, and they will assist directly with species and ecosystem assessments, like the BLM-funded Wyoming Basins Ecoregional Assessment. Therefore, task objectives are to (1) accurately assess and map the distribution of roads, trails, and oil and gas infrastructure; (2) develop, assess, and compare remote sensing methodologies that identify and map the cover, height and distribution of various sagebrush species at three specific study sites; and (3) determine the feasibility of applying these techniques to additional BLM Field offices and at much larger landscapes--such as the state of Wyoming.