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Timber harvest alters structural characteristics in ponderosa pine forests. In the Black Hills, harvested stands with 40-70% overstory canopy cover are managed as sapling/pole (3.0 - 22.9 cm dbh) or mature (> 22.9 cm dbh) stands. Changing the forest structure to two size classes has unknown effects on bird communities in this region. We counted birds in 20 harvested and 20 unharvested ponderosa pine stands during May and June of 1993 and 1994. Harvested stands represented the desired long-term conditions of stands managed for timber production. Forty-seven bird species were recorded; 29...

The wildland-urban interface (W-UI) refers to residential areas surrounded by or adjacent to wildland areas. In recent years, significant W-UI residential fire losses have occurred nationwide in the United States that have focused attention on the principal W-UI problem - losses of life and property to fire. To assess potential ignitions, SIAM uses an analytical approach and worst-case assumptions to establish relationships between the design of a structure and its exposure to fire.

In this chapter, we summarize current knowledge about the effects of fire, logging, and grazing on coniferous forest birds and their habitats. We critically review the results of studies evaluating how these individual factors influence bird numbers, species diversity, nesting success, and habitat use in ponderosa pine forests. Documented and potential interactions among fire, fire exclusion, logging, livestock grazing, and range management are discussed in relation to habitat structure, succession, and avian use. Finally, we outline some areas where further research is needed to better...

This chapter reviews studies on songbird ecology conducted in Arizona, New Mexico, and Colorado; studies from outside this region are mentioned when they bear direct relevance to our primary region. The studies were conducted in sites where ponderosa pine occurred at least in equal coverage with other trees. We also include studies conducted in pine-oak (pine predominant) or oak-pine (oak predominant) woodlands of southeastern Arizona and Southwestern New Mexico. Our review begins with population studies, including research on distribution, abundance, and trends in population numbers. We...

Ponderosa pine forests are important because of their wide distribution, commercial value, and because they provide habitat for many plants and animals. Ponderosa pine forests are noted for their variety of passerine birds resulting from variation in forest composition and structure modified by past and present human use. Subsequent chapters discuss how ponderosa pine forests are associated with different types and number of passerine birds and how humans have modified these forests and affected its occupancy and use by passerine birds. This chapter discusses the ecology and dynamics of...

This publication reviews and synthesizes the literature about ponderosa pine forests of the Southwest, with emphasis on the biology, ecology, and conservation of songbirds. Critical bird-habitat management issues related to succession, snags, old growth, fire, logging, grazing, recreation, and landscape scale are addressed. Overviews of the ecology, current use, and history of Southwestern ponderosa pine forests are also provided. This report is one of the outcomes of the Silver vs Thomas court-settlement agreement of 1996. It is intended for planners, scientists, and conservationists in...

There are ways to improve the LAC process and its implementational procedures. One significant procedural modification is the addition of a new step. This step — which becomes the first step in the process — involves more explicitly defining goals and desired conditions. For other steps in the process, clarifications of concept and terminology are advanced, as are numerous suggestions about how to implement LAC more effectively.

Northern Arizona winters vary within and between years with occasional heavy snows (up to 0.6 m) and extreme cold (overnight lows -18 to -29°C) interspersed with dry periods, mild temperatures (daytime highs reaching 10°C), and general loss of snow cover at all but highest elevations. Lakes in the area may freeze and thaw partially or totally several times during a winter. The freezing and thawing of 1000-ha, 2-m deep Mormon Lake, 34 km south of Flagstaff, Arizona, during the winter of 1994-95 set the stage for the unusual Bald Eagle (Haliaeetus leucocephalus) ice fishing behaviors we...

Geostatistics provides a method to describe the spatial continuity of many natural phenomena. Spatial models are based upon the concept of scaling, kriging and conditional simulation. These techniques were used to describe the spatially-varied surface conditions on timber harvest and burned hillslopes. Geostatistical techniques provided estimates of the ground cover (organic forest floor commonly called duff), which was used to classify burned-over hillslopes into low- and high-severity burn conditions. Rainfall simulation was conducted and the results indicated variability in two important...

Wilderness managers and researchers have experienced implementation of the Limits of Acceptable Change planning system for over a decade. In a sense, implementation of LAC has been a broad scale experiment in planning, with the hypothesis being that LAC processes are more effective approaches to deal with questions of recreation management in protected areas than the carrying capacity paradigm. Workshop participants identified a number of both positive and negative consequences resulting from their experience with LAC. This paper synthesizes these outcomes by discussing the positive...