Management strategies to prevent overfishing while achieving optimum yield vary according to the available data and life history of the fished stock. I evaluated two sets of management strategies for Pacific coast rockfish: strategies to set harvest limits for data-poor stocks, and strategies intended to protect the age structure of...
The relationship between population characteristics and population productivity is fundamental to sustainable fisheries management, but predicting productivity remains a challenging task. Proposed mechanisms driving the variability in productivity at a given population size have included environmental and demographic factors related to the age structure of the population, but the broad-scale...
This project was designed to test the biological effects of three
levels of dietary protein (12.7, 16.3 and 19.3% CP on a dry matter
basis) on high producing Holstein-Friesian dairy cows. Forty five
second lactation or older cows that showed the potential to produce
over 31.75 kg (70 lbs) per...
The fuzzy front end of engineering design can present a difficult challenge, and as such, recent engineering design research has focused on guiding and influencing the way a designer ideates. Early ideation can be especially difficult when attempting to integrate specific design objectives in product design, called Design for X...
Pacific Northwest and California freshwater resources are key elements in the life history and ecology of Pacific salmon and steelhead listed as threatened or endangered under the Endangered Species Act. Risk to listed Pacific salmonid species can be assessed by evaluating the spatial and temporal co-occurrence of salmonid species at...
Depletion-Based Stock Reduction Analysis (DB-SRA; Dick and MacCall, 2011) is a catch-only fisheries stock assessment model that has been developed to estimate an overfishing limit (OFL) in data-poor situations. DB-SRA projects the biomass trajectories of a stock by means of a catch time series and five parameters: the instantaneous, per...
In February 1905 the Oregon State Academy of Sciences formed in
Portland to promote scientific research and diffusion of scientific
knowledge in Oregon. The founders also planned to assist in the
discovery and development of the state's natural resources. The
Academy was the first scientific society in Oregon with professional...
Biological organisms, phenomena and strategies, herein referred to as biological systems, provide a rich set of analogies that can be used to inspire engineering innovation. Biologically-inspired, or biomimetic, designs are publicly viewed as creative and novel solutions to human problems. Moreover, some biomimetic designs have become so commonplace that it...
Interannual variability of Humboldt squid (Dosidicus gigas) occurrence in the northern California Current System is largely unknown. In Oregon, the distribution of this versatile predator and what is influencing their range expansion from Mexico is poorly understood due to the recent nature of their "invasion" and a lack of monitoring....
Ornamental landscapes require considerable amounts of inputs, including but not limited to irrigation, mowing or pruning, fertilization, and pest management. However, school systems have limited budgets, which reduce their access to resources and labor hours. Therefore, the objective of this project is to identify ground covers that can compete with...
Researchers rely on bioeconomic models to guide research and generate fishery management advice for commercial fisheries. Due partly to a paradigm shift towards ecosystem based fishery management, increasing complexity in the characteristics of the problems has meant that bioeconomic simulation models are becoming more prevalent in the fisheries literature. However...
A fundamental objective of ecology and population biology is to identify factors that drive population dynamics and determine the population-level consequences of their interaction with the environment. Studies of reproductive performance can illuminate population dynamic processes, including the links between organismal biology, the environment, and life history theory. A central...
Urban landscape water use is increasingly a focus of water conservation efforts. This is especially true in the arid and semi-arid regions of the western United States where increased demand, environmental concerns, and extended periods of drought have created chronic water shortages. However, until recently, little attention has been paid...