Treesearch

In dealing with predicted changes in environmental conditions outside those experienced today, forest managers and researchers rely on process‐based models to inform physiological processes and predict future forest growth responses. The carbon and oxygen isotope ratios of tree‐ring cellulose (δ13Ccell, δ18Ocell) reveal long‐term, integrated physiological responses to environmental conditions. We incorporated a submodel of δ18Ocell into the widely used Physiological Principles in Predicting Growth (3‐PG) model for the first time, to complement a recently added δ13Ccell submodel. We...

Climate change is projected to impact ecosystem functioning, however its effect on the provision of ecosystem services is uncertain. This is particularly relevant on federal lands which harbor extensive tracts of natural vegetation. We assessed change in four ecosystem services (water runoff, groundwater recharge, carbon storage, and biodiversity) and one disservice (sediment export) in southern California between current and end-of-century (2070–2099). We used five general circulation models ranging from warmer wetter (CNRM-CM5, CCSM4) to hotter, marginally drier (IPSL-CM5A-LR) to hotter...

In this paper, we present a web-based decision support system (DSS)—wSADfLOR—to facilitate the access of stakeholders to tools that may contribute to enhancing forest management planning. The emphasis is on a web-based architecture and a web graphic user interface (wGUI) that may effectively support the analysis of trade-offs between ecosystem services in order to address participatory and sustainable forest management objectives. For that purpose, the wGUI provides remote access to a management information system, enabling users to analyze environmental and biometric data and topological...

Live trapping is a common tool used to assess demography of small mammals. However, live-trapping is often expensive and stressful to captured individuals. Thus, assessing the relative tradeoffs among study goals, project expenses, and animal well-being is necessary. Here, we evaluated how apparent bias and precision of estimates for apparent annual survival, abundance, capture probability, and recapture probability of Humboldt’s flying squirrels (Glaucomys oregonensis) varied with the number of secondary trapping occasions. We used data from forested sites trapped on 12 consecutive...

The Arctic and boreal regions are warming more than twice as rapidly as the rest of the world. The timing of plants’ flowering and fruiting is changing, with implications for insects, wildlife, and people who rely on these resources for food and livelihoods in Alaska. Alaska’s boreal forest will undergo significant functional and structural changes within the next few decades that are unprecedented in the past 6,000 years. The Bonanza Creek Long-Term Ecological Research program is critical to Forest Service research because it is the only Forest Service outpost in the boreal forest, which...

Dispersal among breeding sites in territorial animals (i.e. breeding dispersal) is driven by numerous selection pressures, including competition and spatiotemporal variation in habitat quality. The scale and trend of dispersal movements over time may signal changing conditions within the population or on the landscape. We examined 2,158 breeding dispersal events from 694 male and 608 female individually marked Northern Spotted Owls (Strix occidentalis caurina) monitored over 28 yr on 7 study areas to assess the relative importance of individual (sex, experience), reproductive (annual...

The life-and-death stakes of predator–prey encounters justify the high price of many anti-predator behaviors. In adopting these behaviors, prey incur substantial non-consumptive costs that can have population-level consequences. Because prey knowledge of risk is imperfect, individuals may even adopt these costly behaviors in the absence of a real threat. For example, rather than only avoid hunters, many species categorically avoid all anthropogenic activity. Although hunting seasons only increase risk for specific individuals (e.g., males), non-target individuals may still perceive human...

Keys to Greater Sage-Grouse (Centrocercus uropha-sianus) management are maintenance of expansive stands of sagebrush (Artemisia species [spp.]), especially varieties of big sagebrush (Artemisia tridentata) with abundant forbs in the understory, particularly during spring; undisturbed and somewhat open sites for leks; and healthy perennial grass and forb stands intermixed with sagebrush for brood rearing. Within suitable habitats, areas should have 15–25 percent canopy cover of sagebrush 30–80 centimeters (cm) tall for nesting and 10–25 percent canopy cover 40–80 cm tall for brood rearing...

Biomass mapping is used in variety of applications including carbon assessments, emission inventories, and wildland fire and fuel planning. Single values are often applied to individual pixels to represent biomass of classified vegetation, but each biomass estimate has associated uncertainty that is generally not acknowledged nor quantified. In this study, we developed a geospatial database of wildland fuel biomass values to characterize the inherent variability within and across major vegetation types of the United States and Canada. For vegetation types that had sufficient quantification...