This thesis examined the influence of fall-spawning coho salmon on the density, growth rate, body condition, and survival to outmigration of juvenile coho salmon rearing in beaver ponds on the Copper River Delta, Alaska. During the fall of 1999 and 2000 fish rearing in ponds that received spawning salmon were...
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,...
Intermittent, headwater streams recently have been recognized as important
components of forest ecosystems and have been provided increased protection by the
Northwest Forest Plan. However, few studies have examined their distribution,
dynamics, and ecological roles, such as habitat for wildlife. My goal was to provide
additional information on the ecology...
The coexistence of multiple predators may have important consequences for the structure and function of communities. Interactions between predators may strongly affect their combined direct and indirect effects on prey populations and lower trophic levels. Predators often have size-structured populations, which may result in intraguild predation characterized by complex trophic...
This study was undertaken to evaluate the spatial and temporal characteristics
of riparian groundwater tables adjacent to beaver ponds. The research was
conducted in two parts; in the first portion a two-dimensional, finite-difference
computer model was developed and utilized to simulate groundwater elevations
through time in pond-adjacent aquifers. Two types...
This study investigated the long-term consequences of timber stand removal on the recruitment, physical characteristics, and
spatial distribution of coarse woody debris in small (second- and third-order) streams of the Oregon Coast Range. A chronosequence of stream-stand systems, ranging from 21- to 140-years since disturbance (YSD), were sampled to determine...
Alcoves in some river systems are cooler than the mainstem of the river and provide thermal refugia for aquatic species. An energy balance and sensitivity analysis on 3 alcoves in the Willamette River, Oregon indicate that alcove size and alcove flux determine the degree to which meteorological conditions affect the...
Relationships between resident cutthroat trout (Oncorhynchus clarkii clarkii) and six hydrologic indices were investigated using correlation analysis in two experimental headwater catchments in the foothills of the Cascade Mountains of western Oregon. This investigation was to determine if characteristics of discharge explained inter-annual variability in trout abundance. Eight years of...
Alfalfa sprouts have been implicated in several salmonellosis outbreaks in recent years. Electrolysis of a NaCl solution generates, in the anode side of a two-chamber electrolyzer, acidic electrolyzed oxidizing (EO) water which contains Cl₂, HOC1, dissolved oxygen, and it is characterized by a low pH and a high oxidation reduction...