In this study, I examine the influence of habitat gradients created by the 1980 eruption of Mount St. Helens, Washington USA on a recently established Rainbow Trout (Oncorhynchus mykiss) population in the Spirit Lake basin. My goal was to evaluate the responses of fish in seven streams across a volcanic...
Sustainable elk (Cervus canadensis) habitat management on U.S. Forest Service (USFS) lands involves a complex relationship between management practices and ecological processes. A relatively novel Rocky Mountain elk population (Cervus canadensis nelsoni) on the Plumas National Forest (PNF) in northeastern California became established in the early 2000s, but there is...
Embryonic diapause is a reproductive strategy widespread in the animal kingdom. This phenomenon is defined by a temporary arrest in blastocyst growth and metabolic activity within a quiescent uterus without implantation until the environmental and maternal milieu become favorable for pregnancy to progress. We found that uterine Msx expression persists...
Early seral forests regenerating from stand-replacing disturbances provide unique habitat for many species in productive, temperate forest landscapes and contribute to supporting biodiversity. Population declines in some species associated with early seral forests have prompted concerns about the conservation of these habitats, particularly the characteristic structural and compositional complexity associated...
Aggregate piers have been used for centuries, with increasing occurrence in the last few decades. Their usage has been driven by land development demand and enabled through equipment and engineering improvements. Understanding the principles controlling bearing capacities and serviceability performance has been an ongoing area of interest for structures supported...
Columbian black-tailed deer (Odocoileus hemionus columbianus) are important economically, ecologically, and culturally as an indigenous species in western Oregon. Oregon Department of Fish and Wildlife (ODFW) observed declines in black-tailed deer populations since the late 1980’s and attributes these declines to reduction in quality and availability of habitat, following the...
The seismic response of deep deposits of liquefiable and cyclic-softening susceptible soils has presented the geotechnical profession with significant engineering challenges. Strong ground motions may serve to soften soils under cyclic shear, trigger liquefaction, and produce damaging displacements as a consequence. This study improves the understanding of the in-situ, nonlinear,...
Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order...
Algae can be used in a variety of wastewater systems to capture nutrients while fixing carbon dioxide from the atmosphere. I conducted field trials at three locations in Oregon with both corn and potato crops to assess the agronomic value and environmental impact of using the resulting algal biomass as...
This study uses an existing database of dynamic loading tests of driven piles installed in the Puget Sound Lowlands to improve the reliability of axial performance. First, the unit shaft resistances developed from stress wave signal matching to dynamic records of pile installation are used to develop an effective stress-based...