Treesearch

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 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...

Previous chapters outlined the biology and ecology of boreal owls as well as the ecology of important vegetation communities based on literature from North America and Europe. That technical review provides the basis to assess the current conservation status of boreal owls in the United States. By conservation status, we mean the demographic condition of the species as it relates to the likelihood of local and national persistence of wild populations over the long term. Are populations of boreal owls in the United States currently threatened? Are current land management practices likely to...

Most humans are reluctant to make decisions without thorough knowledge of the consequences of those decisions. Therefore, a desire for further research is almost universal in any complex management arena. The value of further study is determined, in part, by the cost in time and resources to obtain new information and the cost of making incorrect decisions without the desired knowledge. In the case of managing forest lands and conserving boreal owls, our knowledge is so limited that well directed research on distribution, habitat use at many scales linked with studies of local demography,...

The breeding range of great gray owls (Strix nebulosa) in the United States includes portions of Alaska, mountains in the western United States including portions of the Cascades and Sierra Nevada ranges and the northern Rockies, and portions of Minnesota, Michigan, Wisconsin, and New York (see Chapter 14 and Map 3). The species is sometimes observed in more southerly states during severe winters. Based on the species' documented distribution (see National Geographic Society 1987, Johnsgard 1988, and others), the owl may occur on National Forests across seven Regions. To document the...

The great gray owl (Strix nebulosa) is the longest, but not heaviest, of the northern forest owls. Distributed holarctically across the boreal forests of North America and Eurasia, the great gray owl extends its range southward into the contiguous states by inhabiting forests other than the boreal type. The subalpine and montane forests of the Cascade Range, Sierra Nevada Range, and the Rocky Mountains support great gray owl populations in central Washington; central and northwestern Oregon; north-central and eastern California; northern, central, and southeastern Idaho; western Montana;...

Many kinds of basic information are required to devise a comprehensive and well-informed conservation strategy for this species. It is imperative that a unified, centrally directed approach be taken to obtain this information. Central oversight will make the effort more efficient and cost effective.