Stocks of salmon are declining in the Pacific Northwest. Based on region-wide studies that list and categorize the status of salmon stocks (Nehlsen et al., 1991; Huntington et al., 1994; and Nawa, 1995), I analyze the watersheds where stocks of salmon spawn for several anthropogenic variables, most of which are known to affect salmon. A total of 202 watersheds (stocks of salmon) in Washington, Oregon, California, and Idaho are coded for 13 anthropogenic variables such as dams, forest, agriculture, human population, hatcheries, Indian tribes, and watershed organizations. Most variables are ordinally coded 1 to 5 with the help of maps, some survey results, and visual assessment. Hypotheses are that the human activities that are detrimental to the health of salmon are associated with the poor status of salmon stocks in watersheds where they spawn. Salmon watersheds are also analyzed according to ecoregions and salmon management regions. Principal components analysis is performed to reduce the number of anthropogenic variables into factors. Kendall's tau, partial correlation, multiple linear regression, logistic regression, and discriminant analyses are performed separately for five species/races of salmon (coho, spring chinook, summer chinook, fall chinook, winter steelhead) and for the watershed average for salmon stock status, against the anthropogenic variables and factors. Statistical results using both variables and factors support most of the hypotheses relative to salmon and anthropogenic activities in watersheds. Results suggest that the 5 species/races of salmon are associated differently with most anthropogenic activities. The greater the amount of dams below watersheds where salmon spawn, the less healthy the salmon stocks. Summer chinook are least healthy where hatcheries are absent, while wild and scenic rivers are associated with healthier spring chinook. Coho are least healthy where there is more agriculture, more human population, and less forest. Fall chinook are least healthy where there is more US Forest Service land. Winter steelhead are least healthy where hatcheries are absent and less Indian tribal land. Ecoregional differences coupled with the absence of dams on the Coast compared to the Columbia Basin are associated with healthier coastal stocks. / Graduation date: 1998

No description available.

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 complexities. I investigated factors that influenced the susceptibility of western toad (Bufo boreas), Cascades frog (Rana cascadae), and Pacific treefrog (Hyla regilla) embryos to infection with the fungal pathogen Saprolegnia ferax. I found that there were considerable interspecific differences in susceptibility of anuran embryos to infection with Saprolegnia. Interspecific differences can be attributed to differences in egg-laying behavior and sensitivity to ambient levels of ultraviolet radiation. I studied the effect of Saprolegnia on competitive interactions between larval R. cascadae and H. regilla. The presence of Saprolegnia differentially affected larval recruitment of the two species and mediated competitive interactions. These results suggest that pathogens may have strong effects on species interactions and thus, when present may have strong influences on community composition. I examined population differences in response of native red-legged frogs (R. aurora) to introduced bullfrogs (R. catesbeiana). Syntopic R. aurora tadpoles reduced their activity and increased their refuge-use when presented with the chemical cues of R. catesbeiana, whereas allotopic R. aurora did not. Predation by R. catesbeiana was lower for syntopic R. aurora compared with animals from allotopic populations. Individuals that are unfamiliar with novel, introduced organisms may not possess adaptations that would prevent a negative encounter. In field experiments I demonstrated that introduced R. catesbeiana, and smallmouth bass Micropterus dolomieui, influenced the microhabitat use, growth, and survival of larval and metamorphic R. aurora. These results illustrate the potential complexities of interactions between native and exotic species. These results also stress the importance of understanding the mechanisms of interactions between native and exotic species to allow for the persistence of native biodiversity. / Graduation date: 1998

Thesis (M.L.S.)--University of Michigan, 1944. / "Designed to supplement the Subject index to the history of the Pacific Northwest and of Alaska ... prepared by Katharine B. Judson, and published by the Washington State Library, in 1913"--Introd. "Library Science 321." At head of title: University of Michigan, Department of Library Science.

Over the past decade, feeder cattle backgrounders in the Pacific Northwest have been subject to sharp price fluctuations for their output. The result has been variable profits and losses. This situation creates a need for management and marketing techniques which can provide Pacific Northwest cattle ranchers with protection against price risks while enhancing the profitability of their operations. Recent economic literature has shown hedging with futures contracts to be an effective tool for mitigating risk and/or increasing the net revenues of cattle producers in a number of regions of the United States. The objective of this research was to determine whether hedging with futures contracts could have increased the profitability of Pacific Northwest feeder cattle production while decreasing the effects of price volatiliy. To realize this objective, the economic performance of alternative hedging strategies were evaluated for several methods of feeder cattle backgrounding indigenous to the Pacific Northwest region. Four hedging strategies -- routine, moving average, profit objective, and triangular probability distribution — were evaluated for hedging the output of four simulated production systems. The mean and standard deviation of annual net returns were computed for each hedging strategy to serve as measures of profitability and risk, respectively. The results of not hedging were also obtained to provide a basis for comparing alternative hedging programs. Sample t and F tests were conducted to determine whether there were statistically significant differences between the means and standard deviations of the unhedged and hedged positions. Dominant hedging strategies were then identified for each production system. Based on the results of the mean-variance analysis, it appears that the use of selective futures market hedging strategies would have provided greater and more stable levels of profit compared to the net incomes obtained without hedging. Sample t and F tests, using 80 and 90 percent levels of significance respectively, showed that hedging could have significantly decreased the variability of the producer's flow of income without significantly changing the operation's average profitability. Moving average, profit objective, and triangular probability distribution strategies were dominant, increased average profitability, and significantly lowered risk for at least one production system each. Overall, moving average strategies generated the highest mean profits with the greatest risk. Profit objective strategies generally resulted in lower mean profit than moving average strategies but with less risk. The risks and returns from hedging with triangular probability distribution strategies were usually between the moving average and profit objective procedures. Strategies which performed well in this study should also perform well in the future if conditions in the feeder cattle markets do not vary substantially from those of the previous decade. Thus, hedging with futures market contracts may provide the Pacific Northwest feeder cattle producers with protection against price risk and enhanced profitability. / Graduation date: 1985

The objective of this study was to ascertain the magnitude and distribution of rainfall over coastal waters of the northwestern United States and to compare values with those at nearby land stations. Precipitation was measured with gauges at Totem, rainfall amounts were assessed from weather reports at lightships off the coast, and precipitation frequencies at lightships and land stations were examined. Results from the three methods were quite consistent; precipitation. on at sea was only about one-third that at coastal land stations. These values are appreciably less than previous estimates of oceanic rainfall in this area, and they support the view that a significant horizontal gradient of precipitation may exist between the coast and open sea. Rainfall typically occurs both at sea and ashore on the same day, but it rains fewer hours at sea. The relative amount of rain at sea varies with the type of atmospheric system, and rainfall at the coast appears to be intensified by frictional processes. Estimates of evaporation minus precipitation are less negative than earlier ones; consideration of their relation to surface salinity leads to distributions that are in good agreement with oceanographic knowledge. The newer values suggest that in this region the heat gain by the atmosphere may be less (but moisture entrainment may be greater) than was thought. / Graduation date: 1973

Graduation date: 1966

Graduation date: 1970

Graduation date: 1995

Thesis (Ph. D.)--University of Oregon. / Bibliography: p. [54]-55. Also available on the World Wide Web.