Environmental History of Estuarine Dissolved Oxygen Inferred from Trace-Metal Geochemistry and Organic Matter

Environmental history recorded in sediments can track estuarine water quality through the use of geochemical and biological proxies. I collected sediment cores from two locations in the Coos Bay Estuary, at South Slough and Haynes Inlet, spanning from ~1680 AD to the present. To address the historical water column oxygen in the estuary I measured geochemical proxies including organic matter, magnetic susceptibility, and redox-sensitive metals to calibrate against a detailed 15-year record of dissolved oxygen observations.

Agent-based Tsunami Evacuation Model: Life Safety and Network Resilience

Natural disasters could result in unnecessary loss of life and disproportionat​e suffering to families and communities if evacuation plans are not in place or understood by the public. In the Pacific Northwest, a magnitude 9.0 earthquake and tsunami from the Cascadia Subduction Zone (CSZ) represents one of the most pressing natural disasters with an astonishing high 7%-12% chance of occurrence by 2060.

A Landscape-Scale Watershed Assessment Method to Support Fish Passage Restoration in Puget Sound, Washington State: An Analysis for the Fish Barrier Removal Board

In 2014, the Washington State Legislature directed the creation of the Fish Barrier Removal Board (FBRB), a multi-entity committee tasked with the development of a statewide strategy for removing anadromous fish barriers. The strategy shall identify watersheds with the greatest potential for salmon and steelhead recovery and implement the removal of multiple barriers within those watersheds. Prioritizing whole watersheds for barrier removal is a new and untested approach to fish passage restoration in Washington State.

Evaluating coastal protection services associated with restoration management of an endangered shorebird in Oregon, U.S.A.

Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem services offered by dunes and beaches is challenging when ecosystem services interact across the landscape. Management focusing only on one ecosystem service may result in unintended consequences and trade-offs between other key services.

Potential Impacts of Timber Harvesting, Climate, and Conservation on Sediment Accumulation and Dispersal in the South Slough National Estuarine Reserve, Oregon

Accurate sediment flux histories are critical data for deciphering the relative importance of climate and land use factors such as logging and road construction on sediment production and deposition. We use 210Pb activities derived from sediment cores taken on the tidal flats of the South Slough of the Coos Bay estuary to establish temporal variations in sediment accumulation rates. We determined that average deposition varied between 0.4 and 0.81 cm/yr based on two ~80 cm sediment cores.

Orientation Behavior and Feeding Ecology of the Scyphomedusa Chrysaora fuscescens

Chrysaora fuscescens is a cnidarian scyphomedusa that occurs in the northern California Current. In this upwelling system, medusae are seasonally abundant, and individuals can ingest 10-60% of the standing stock of vulnerable zooplankton taxa per day. Yet little is known about this medusa’s feeding ecology. Using laboratory pseudokreisels, C. fuscescens feeding rates and behavior were quantified in the presence of a controlled flow field. C.

An Evaluation of the Effects of Hatchery and Management Practices on Geomagnetic Orientation Behavior in Juvenile Pacific Steelhead Trout (Oncorhynchus mykiss)

Numerous populations of salmon and trout undergo extensive migrations, migrating from freshwater to the sea and throughout ocean basins. Years later they return to their natal streams with remarkable accuracy and precision. The outward migration is accomplished without the benefit of following experienced migrants or prior individual experience. Evidence suggests that Pacific salmon and trout use the earth’s geomagnetic fields when undertaking these migrations.

Essays on Regional Economic Impact Assessment and Demand Analysis Using Disaggregated Data

The appropriate use of disaggregated economic data not only improves the accuracy and robustness of economic analyses, but also extends the existing economic models to address new aspects of the issue. This dissertation consists of three essays: two essays use disaggregated economic-engineering data to address spatial heterogeneity in economic losses and regional interdependencies for Tsunami impact assessment and resilience planning in State of Oregon.

Oregon’s Fishing Community Adapting to Change in Policy, Management, and Markets: Documenting Women’s Roles and Adaptive Capacity in an Evolving Industry

Commercial fishing research often focuses on ecological (gear, stock assessment, traceability) or economic factors. Truly understanding the social-ecological system requires considering the entire “human dimension” and this includes the social, cultural, and legal/policy aspects as well. An understudied yet important factor is women’s contribution to fishing at the family and community level.

An Experimental Investigation of the Effects of Temperature and Dissolved Oxygen on the Growth of Juvenile English Sole and Juvenile Dungeness Crab

In the past two decades, occurrences of summertime upwelling-driven low dissolved oxygen (DO) events, or hypoxia, have increased along the northeast Pacific coast. If hypoxic events are severe enough to cause marine species mortality, the areas affected are often called “dead zones.” In 2002 and again in 2006, the events were lethal, resulting in mass invertebrate and fish kills. Many organisms are impacted by these events, but less mobile juvenile fishes and crabs are potentially more vulnerable to the long-term effects of these stressful conditions than adults.