Snags provide critical habitat for nearly one-third of wildlife species in forests of the Pacific Northwest, so historic declines in snags are thought to have had a strong impact on biodiversity. Resource managers often create snags to mitigate the scarcity of snags within managed forests, but information regarding the function...
Developing accurate predictive distribution models requires adequately representing relevant spatial and temporal scales, as these scales are ultimately reflective of the relationships between distributions and influential environmental conditions. In this research, we considered both spatial and temporal scale and the influence each has on predicting broad-scale distributions of two disparate...
Population trends and patterns in species distributions are the major currencies used to examine responses by biodiversity to changing environments. Effective conservation recommendations require that models of both distribution dynamics and population trends accurately reflect reality. However, identification of the appropriate temporal and spatial scales of animal response, and then...
The combined effects of habitat loss, degradation, and fragmentation pose a serious threat to Earth's biodiversity, imperiling even relatively common species. 'Habitat' is necessarily a species-specific concept, and investigations of bird diversity relationships and subsequent efforts to prioritize conservation areas, are challenged by the difficulty of estimating complex habitat gradients...
Bird-vegetation associations are a base for bird conservation and management, as well as for predictions of the effects of resource management and climate change on wildlife populations. A recent shift in forest management priorities from timber production to native species' habitat conservation on federal lands has emphasized the need to...
Fire severity is hypothesized as an important driver of bird responses to wildfire. For those species that typically respond negatively to increasing severity, Accessibility of high-severity burned forest may be dependent on the proximity of unburned or low-severity burned forest to meet all of the needs of breeding bird species...
Recent evidence suggests that population declines of some avian species may be driven primarily by reduced quantity and diversity of early-successional habitat on the breeding grounds. Increasing intensity of forest management on private lands and decreased harvest rates on federal lands has resulted in a loss of the diverse early-successional...
High severity fire is a historical and integral disturbance process in coniferous
forest types. Compounded disturbances such as multiple fires or post-disturbance
management activities are increasingly common, but ecological responses are not well
understood and may represent novel types of disturbances. I studied bird and small
mammal communities in the...
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4.1. Mean density of seventeen bird species from unlogged plots in severely
burned forest of
Previous research examining the influences of post-fire salvage logging on abundances of birds has focused primarily on the response of cavity-nesting species. There is limited research in regard to the impact of salvage logging on a broader range of bird species. In addition, little is known about how different intensities...
In the interest of meeting multiple forest management goals that include maintenance of wildlife, particularly cavity-nesting birds, uneven-aged silvicultural treatments are used increasingly in the Pacific Northwest. However, questions remain regarding the responses of cavity-nesting birds and residual green trees to different harvest intensities and patterns. To study these issues,...
Characterization of canopy structure, the horizontal and vertical distribution of the tree crowns in a forest, is important for the management of forests in the Pacific Northwest. The canopy is an important habitat element for many wildlife species, canopy structure affects understory development, and influences various natural processes, such as...
Fifty-seven species of wildlife rely on or frequently use snags for breeding, roosting, or denning in Oregon and Washington. Several publications offer information on use of snags by wildlife, influence of management activities on snags and snag users, and approaches to managing snags to benefit wildlife. Because of the diverse...
Breeding bird communities were examined in 18 managed Douglas-fir stands in 6 age classes from 5 to 34 years old in spring and early
summer, 1993 on the Detroit Ranger District, Willamette National Forest, Oregon. The range of seral stages included early shrub/sapling, late shrub/sapling, and pole. In general, the...
Riparian zones provide habitat for breeding birds in the semiarid western United States; however, there are few data available that address the effects of livestock grazing strategies on riparian habitats and avian communities. Documenting avian community composition in different riparian vegetation communities and relating vegetation communities to livestock grazing strategies...
The ecology of female mallards (Anas platyrhynchos) and their
broods was studied during 1988-90 on Lower Klamath National Wildlife
Refuge, California. Survival of 127 radio-marked ducklings from 64
broods was 0.18 to 10 days of life, and 0.37 and 0.34 to fledging for
1988, 1989, and 1990, respectively. For the...
Previous studies of bird communities in the mid-Willamette Valley, Oregon, indicated that Oregon white oak (Ouercus garryana) stands supported more cavity-using bird
species than sympatric stands of Douglas-fir (Pseudotsuga menziesii). Mature Oregon oak stands are being harvested and few are regenerating. I compared cavity availability for hole-using fauna among 10...
I studied abundance patterns and habitat use of eight cavitynesting bird species in the Coast Ranges of Western Oregon during the
spring and summer of 1985 and 1986. Three age classes of unmanaged Douglas-fir (Pseudotsuga menziesii) stands were selected for study:
young (40-80 yrs), mature (80-200 yrs), and old-growth (>200...
Populations of breeding birds and forest composition and structure were examined in preconimercially thinned and unthinned ponderosa pine (Pinus ponderosa Laws.) stands in east-central Washington. Stands were composed of predominantly ponderosa pine with a multi-aged structure made up of small even-aged clumps. Thinning reduced the
density and foliage volume of...