Samples targeting crustacean zooplankton were collected from 3 upper Willamette Basin reservoirs during May-August 2015. Van Dorn sampling devices were used to collect samples at discrete depths from Fall Creek Reservoir, Lookout Point Reservoir, and Hills Creek Reservoir.
Zooplankton samples were collected during daytime and nighttime corresponding with the new...
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,...
The relation of nutria (Myocastor coypus) feeding to total abundance, species composition, and seasonal use of the marsh flora on
the William L. Finley National Wildlife Refuge was studied during
1969 and 1970. Nutria numbers were estimated by livetrapping. Food
habits data were compiled from observations of feeding nutria. Phenology,...
I used current water management practices in central and eastern Oregon and Washington as natural experiments to quantify the effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies. Reduced discharge had direct (e.g. decreased velocity and wetted habitat) and indirect (e.g. increased conductivity and temperature) effects...
Twenty-five gabion-type structures across the main stem and
tributaries of the Siuslaw River in the Oregon Coastal Range, installed
to expand the available spawning area for fish, were investigated for
their ability to perform gravel control functions such as trapping bedload
carried by the stream or holding gravel placed behind...
An impounded estuary was employed to study primary productivity, community respiration, and community structure as they
related to seasonal and temporal succession, salinity, and water
temperature. Plankton metabolism was studied by means of the
light-and dark-bottle technique. Benthic community metabolism
was determined by using the "diurnal oxygen curve" method.
Four...
This thesis reports a portion of a general ecological study of
a stream under conditions of controlled flow and low levels of organic
enrichment. It is concerned with the effects of experimental variations
of light intensity and concentration of soluble organic enrichment
imposed on seasonal variations of temperature and total...
Wetland restoration success in attaining wildlife conservation goals can be confounded by the presence of multiple biological invaders. Wetland management activities typically target invasive plants, but bottom-up responses of higher trophic levels in novel communities are difficult to predict. We surveyed plant and amphibian assemblages at 26 sites enrolled in...