Treesearch

This past year has been a period of transition for the Rocky Mountain Research Station. In 2006, we identified the need to move from an organization of approximately 30 research work units whose work was formed around national Strategic Program Areas, to a more streamlined team-oriented organization composed of Science Programs and Research, Development, and Application programs (RD&A's). Much planning, study, and employee input went into how the new Station would be configured and managed.

The ability of populations to be connected across large landscapes via dispersal is critical to longterm viability for many species. One means to mitigate population isolation is the protection of movement corridors among habitat patches. Nevertheless, the utility of small, narrow, linear features as habitat corridors has been hotly debated. Here, we argue that analysis of movement across continuously resistant landscapes allows a shift to a broader consideration of how landscape patterns influence connectivity at scales relevant to conservation. We further argue that this change in scale...

The following matrix provides a comparison of wilderness laws around the world. This matrix is divided into four parts, each focusing on a key area of wilderness legislation: the definition of wilderness; the overall legislative purpose; uses allowed by the legislation; and administration and management requirements under law. A more thorough analysis of individual wilderness laws follows in the ensuing chapters. The purpose of this matrix is to provide a highly condensed overview of the subject matter and to facilitate quick comparisons of the different approaches used in different...

Intrusion by humans into wildlife habitat during recreational activities has become a worldwide conservation concern. Low levels of intrusion, which occur frequently in many wildlands, could influence use of sites by red squirrels (Tamiasciurus hudsonicus) and have important ramifications for conservation. Red squirrels can influence forest composition and regeneration by feeding on conifer buds, seeds, and vascular tissues, and they prey on avian nests. Attraction of red squirrels could increase the risk of these activities, whereas displacement of red squirrels may exacerbate demographic...

Wilderness managers must balance providing access for wilderness recreation with protecting the special experiences wilderness provides. This balancing act is particularly challenging at popular destinations close to large metropolitan areas. Such destinations provide substantial societal benefits by allowing respite from city life and immersion in natural environments for thousands; however, the thousands that throng to these places detract from the wildness and sense of solitude that wilderness should provide. Managers are left wondering what sorts of experiences are appropriate in such...

This paper describes the Local Analysis and Prediction System (LAPS) and the 20-km horizontal grid version of the Rapid Update Cycle (RUC20) atmospheric analyses datasets, which are available as part of the Cold Land Processes Field Experiment (CLPX) data archive. The LAPS dataset contains spatially and temporally continuous atmospheric and surface variables over Colorado, Wyoming, and parts of the surrounding states. The analysis used a 10-km horizontal grid with 21 vertical levels and an hourly temporal resolution. The LAPS archive includes forty-six 1D surface fields and nine 3D...

The Cold Land Processes Experiment (CLPX) had a goal of describing snow-related features over a wide range of spatial and temporal scales. This required linking disparate snow tools and datasets into one coherent, integrated package. Simulating realistic high-resolution snow distributions and features requires a snow-evolution modeling system (SnowModel) that can distribute meteorological forcings, simulate snowpack accumulation and ablation processes, and assimilate snow-related observations. A SnowModel was developed and used to simulate winter snow accumulation across three 30 km x 30...

Bird species that specialize in the use of burned forest conditions can provide insight into the prehistoric fire regimes associated with the forest types that they have occupied over evolutionary time. The nature of their adaptations reflects the specific post-fire conditions that occurred prior to the unnatural influence of humans after European settlement. Specifically, the post-fire conditions, nest site locations, and social systems of two species (Bachman's sparrow [Aimophila aestivalis] and red-cockaded woodpecker [Picoides borealis]) suggest that, prehistorically, a frequent,...

Widespread encroachment of the fire-intolerant species Juniperus virginiana L. into North American grasslands and savannahs where fire has largely been removed has prompted the need to identify mechanisms driving J. virginiana encroachment. We tested whether encroachment success of J. virginiana is related to plant species diversity and composition across three plant communities. We predicted J. virginiana encroachment success would (i) decrease with increasing diversity, and (ii) J. virginiana encroachment success would be unrelated to species composition. We simulated encroachment by...

This study investigated the effect of cumulative overland flow on rill erodibility and critical shear stress on native surface roads in central Idaho. Rill erodibility decreased exponentially with increasing cumulative overland flow depth; however, critical shear stress did not change. The study demonstrated that road erodibility on the studied road changes over the course of one or more consecutive overland flow events. Therefore, model simulations that fail to take into consideration this change will probably over-estimate sediment yields. An exponential function describing the relationsh...