To effectively manage for biodiversity at broad, ecosystem scales, the influences of habitat structure at multiple spatial scales on vertebrate species must be understood. There are few studies on the broad-scale habitat requirements of stream amphibians despite their importance in streams in forest ecosystems in the Pacific Northwest (PNW) as...
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...
My dissertation focuses on the evolutionary forces that have shaped the chemical signaling system of plethodontid salamanders. Pheromones mediate two phases of plethodontid reproduction: mate attraction prior to courtship and female persuasion during courtship. Substrate-borne chemical signals are believed to play an important role in mate attraction for these animals....
We have a poor understanding of the biotic communities in zero-order basins, drainages extending from ridgelines to the initiation of first-order streams. This study describes baseline plant and amphibian composition in unmanaged zero-order basins in the Oregon Coast Range. Specifically, I studied: i) the spatial distribution and diversity of species,...
I examined two amphibian communities to assess factors
that may impact amphibian biodiversity. The results suggest
that the potential factors which influence the maintenance
of amphibian biodiversity are multi-faceted and thus,
attempts to understand these factors must reflect these
I investigated factors that influenced the susceptibility
of western toad...
Headwater streams and their riparian zones are a common, yet poorly understood,
component of Pacific Northwest landscapes. I sought to describe the ecological significance of
headwater stream riparian zones as habitat for forest-floor invertebrate communities, and to
assess how alternative management strategies for riparian zones may impact these communities.