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Stream reaches that have been rested from livestock grazing appear to have stable banks and more bank undercuts than grazed stream sections. Ungrazed reference streams that are similar in parent geology, precipitation, channel type, habitat types, drainage area, and stream width had greater bank stability values and lower width-todepth ratios than those of grazed and rested management sections of Silver King Creek. Power curve analysis was used to suggest the sample sizes required to monitor progress toward the desired condition.

Variance approximations are derived for the weighted and unweighted kappa statistics, the conditional kappa statistic, and conditional probabilities. These statistics are useful to assess classification accuracy, such as accuracy of remotely sensed classifications in thematic maps when compared to a sample of reference classifications made in the field. Published variance approximations assume multinomial sampling errors, which implies simple random sampling where each sample unit is classified into one and only one mutually exclusive category with each of two classification methods. The...

The bark beetle antiaggregative pheromones, verbenone and ipsdienol, were tested in protecting heat-injured lodgepole pine (Pinus contorta Dougl. ex Loud.) from mountain pine beetle (Dendroctonus ponderosae Hopkins) infestation in the Sawtooth National Recreation Area in central Idaho. Peat moss was placed around 70 percent of the basal circumference of lodgepole pines. When the peat moss was ignited, it simulated the smoldering of natural duff, generating temperatures that killed the cambium. The four treatments tested were uninjured tree, heat-injured tree, heat-injured tree treated with...

Great gray owls (Strix nebulosa) inhabit forests, but not all forests possess identical characteristics. To understand the owl, we must understand the dynamics of the vegetation communities that support them. Those dynamics operate differently in the Northern Rocky Mountains and the Cascade-Sierra Nevada complex, both of which are inhabited by great gray owls.

Previous chapters outlined the biology and ecology of great gray owls as well as the ecology of this species in the western United States. That technical review provides the basis to assess the current conservation status of great gray owls in the United States. Are populations of great gray owls in the United States currently threatened? Are current land management practices likely to lead toward the peril of these populations?

Current understanding of great gray owl biology and ecology is based on studies of less than five populations. In an ideal world, a strong conservation strategy would require significant new information. However, current knowledge suggests that conservation of this forest owl should involve fewer conflicts than either the boreal or flammulated owl. The mix of forest habitats used by great gray owls fit patterns that occur in managed forest landscapes when the maintenance of mature and older forest is an integral part of management planning. Therefore, immediate threats to the persistence...

The flammulated owl (Otus flammeolus) is a tiny, common predator on invertebrates that nests in cavities in western North American coniferous forests. It was thought by early workers to be rare (Bendire 1892, Bent 1938), but more recent opinion is that it is common but secretive (Marshall 1967, Winter 1971, 1974, Richmond et al. 1980). The combination of its very small size (Earhart and Johnson 1970), ventriloquial but low-pitched voice (Miller 1947), strictly invertebrate diet (Ross 1969, but see below), and probable migratory behavior (Winter 1974, Balda et al. 1975, but see Johnson...

The status of the flammulated owl will be evaluated in this chapter by asking a series of critical questions about the species and its habitat. Answers to these questions will be used to reach one of the following conclusions: (1) populations in the United States are secure and will likely remain so given current land management practices; (2) populations are in peril (declining or experiencing some demographic trauma) or are likely to be in peril in the future given current land management practices; or (3) we currently have insufficient knowledge to determine the conservation status of...

The range of boreal owls (Aegolius funereus) in the United States includes Alaska, the mountains of the western United States, and the northern tier states from the Atlantic to Pacific (see Chapter 9). Based on the species' documented distribution (see National Geographic Society 1987, Hayward et al. 1987, Johnsgard 1988, and others) the owl may occur on 81 National Forests across 7 Regions. To document the management status of the boreal owl throughout its range we queried management personnel on all National Forests where the species is likely to occur.

The boreal owl (Aegolius funereus), known as Tengmalm's owl in Eurasia, occurs throughout the holarctic in boreal climatic zones. This medium-size owl (100-170 g) occupies boreal and subalpine forests in an almost continuous circumboreal distribution that extends from Scandinavia eastward across the northern forests of Siberia and from Alaska across Canada to the Atlantic (Dement'ev and Gladkov 1954). On each continent, disjunct populations occur in mountains south of the broad transcontinental boreal forest populations (Cramp 1977, Voous 1988). Boreal owls in the mountain regions of...