I studied selection of winter den sites by northern flying squirrels (Glaucomys sabrinus) in forests of the Oregon Cascades. Fifty-six squirrels were radio-collared in three managed, 80- to 1 30-year-old Douglas-fir stands on the Umpqua Nationa Forest during the winters of 1994-95 and 1995-96. Squirrels were located at their den...
Knowledge about vegetation patterns and ecological processes in unmanaged, late-successional
watersheds is needed to provide a foundation for forest management strategies
aimed at conserving native biodiversity. I examined influences of environmental variability
and disturbance history on forest structure and composition in the Cummins Creek
Wilderness, located on the central Oregon...
The species compositions and densities of the littoral and pelagic zooplankton
assemblages in Crater Lake were compared. The littoral and pelagic zooplankton
assemblages of most lakes are typically different due to different habitat conditions in the
two zones. The littoral zone of Crater Lake lacks many of the habitat characteristics,...
Salmonberry community structure was examined in alder-dominated
riparian buffer strips in the Oregon Coast Range. Salmonberry growing on slopes
was found to respond differently, to both characteristics of the buffer strips and
to environmental factors, than salmonberry growing on terraces.
Salmonberry, as measured by total height, number of ramets or...
The influence of loss of diversity on community dynamics and ecosystem functioning has recently received considerable attention. Although study of biodiversity has a long history within ecology, empirical investigations exploring consequences of loss have been rare. Because many factors confound diversity comparisons, experimental manipulations of diversity offer the most direct...
The National Park Service initiated a backcountry campsite restoration project
in 1987 to restore native vegetation on severely degraded campsites in three subalpine
lake basins in Yosemite National Park. Restoration treatments included soil
scarification, transplanting, manual seeding and site protection. Eight of the treated
campsites were monitored in 1990 to...
National Forest management in the Pacific Northwest is shifting
from a focus on commodity production to ecosystem management, in which
the health of the entire forest ecosystem is considered, rather than that
of a few key species. Ecosystem management includes retention of some
live trees following timber harvest (green-tree retention)...
Pendent Usnea species were collected in western Oregon and examined.
Character states, such as cortex-medulla-axis ratio; fibril length; papilla diameter;
branching patterns; and presence or absence of fibrils, papillae, soredia, isidia; plus
chemistry, were recorded and analyzed by inspection for differences. Historical
names were researched in the literature. A comparison...
As ecologists are being called upon to predict the consequences of human
perturbations to natural communities, an important goal is to understand what factors
drive variability or consistency in nature.
In the rocky intertidal of San Juan Island, Washington, a comparative
experimental approach was used to investigate spatial and temporal...
The general objective of this study was to develop
models and datasets that would significantly advance our
ability to assess the current and future effects of global
change on the biosphere. The focus was in two areas: (1)
preparing environmental datasets at regional to small
watershed scales; and (2) developing...
