There is a paucity of information concerning the invertebrate food resources available to juvenile salmonids in the Columbia River as they migrate seaward. Construction of mainstream dams has altered the temperature cycle, flow regime, and substrate which indigenous invertebrates were adapted to. Studies on how the macroinvertebrate community has adapted to these alterations have been neglected. This study was undertaken to help fill this void. Macroinvertebrate drift samples were collected over a three year period in the Columbia . River downstream from Bonneville Dam. Samples were collected with a D-ring plankton net fished on the bottom for one-half hour. Two sites were sampled; Ives Island (RKM 230), from 1987 through 1989, and Lady Island (RKM 193), in 1988 and 1989.

The average size and age of chinook salmon (Oncorhynchus tshawytscha) caught in commercial fisheries along the Pacific Coast of North America have decreased substantially in this century. These declines might be caused in part by changes in size and age at maturity within the stocks contributing to those fisheries. Upriver Brights (Brights), a stock of fall chinook salmon in the Columbia River, are one of those stocks. The purposes of this study were to (1) determine if average size and age at maturity of Brights have declined, (2) gain a better understanding of the factors that may contribute to such declines, and (3) describe potential consequences of these changes. Data from in-river fisheries suggest that the average weight of mature Brights returning to the Columbia River has decreased approximately 2.7 kg since the 1910s, an average rate of about 0.1 lb·yr⁻¹ (45 g·yr⁻¹ ). Most of the potential biases in these data tend to make this estimate conservative. Insufficient data were available to describe changes in average age at maturity. There are many potential causes for the decline in average size of mature Brights, including factors that affect very early life stages. Other researchers have determined that size at maturity appears to be highly influenced by inheritance, gender, and growth rate. I describe how maternal size can influence -- through time of spawning, choice of spawning site, and egg size -- the viability of the young, which carry the dam's genes for size. The size-related ability to produce viable offspring may have been changed by modifications in the environment. Very little is known about how changes in the natural environment for spawning, incubation, and rearing may have contributed to a decline in average size at maturity. Artificial propagation and rearing, such as at Priest Rapids Hatchery, seems to produce adult Brights that are smaller, younger, and more likely to be male than their natural counterparts. The net result is that the average hatchery fish may have only about 0.80 of the reproductive potential of the average natural fish. Changes in growth conditions in the ocean probably did not contribute to the change in size, although the ocean fisheries of Southeast Alaska and British Columbia appear to select, in the genetic sense, against large size and old age in Brights. Since 1978, in-river commercial fisheries have caught larger Brights and a higher proportion of females than are found in the escapement of the Priest Rapids Hatchery component of the stock, but the fisheries impact the two sexes differently by taking the larger males and the smaller females. The effect on the natural component may differ because of their apparently larger average size. I found no evidence that larger fish or more females were caught when 8-in. minimum restrictions were in effect on gillnet mesh size relative to periods when mesh size was not restricted. Impounding the mainstem during the last 50+ yr may have removed obstacles to migration (e.g., Celilo Falls) that selected for large size in Brights, but that hypothesis could not be tested. The perserverance of larger and older phenotypes in the Bright stock suggests that countervailing selection -- perhaps during spawning, incubation, and/or early rearing -- may have resisted the effects of a century of size- and age-selective fisheries. That resistance, however, may reduce the productivity of the stock. Declines in average size and age at maturity can have undesireable consequences. Lower average size means less biomass landed and lower commercial value. Lower average fecundity and a diminished ability to reproduce in some environments are also expected. Loss of size and age classes may reduce the ability of the stock to adapt to environmental variations. These results are relevant to several management practices. A holistic approach to fishery management issues is necessary to avoid erroneous conclusions based on narrow perspectives. Measuring reproductive potential of the catch and escapement would be superior to the conventional practice of simply counting numbers of fish. Many aspects of artificial propagation can be improved, including broodstock aquisition, mating regimes, and rearing practices. Stock abundance is a major factor in determining the effect of many management practices on the stock. In general, fisheries managers must be mindful that they manage very complex natural systems. / Graduation date: 1992

River systems, such as the Columbia River in the Pacific Northwest, USA have been influenced by human activities, resulting in changes to the physical processes that drive landform evolution. This work describes an inventory of landforms along the Columbia River estuary between the Pacific Ocean and Bonneville Dam in Oregon and Washington. Groupings of landforms are assigned to formative process regimes that are used to assess historical changes to floodplain features. The estuary was historically a complex system of channels with a floodplain dominated by extensive tidal wetlands in the lower reaches and backswamp lakes and wetlands in upper reaches. Natural levees flank most channels in the upper reaches, locally including areas of ridge and swale topography and crevasse splays that intrude into backswamps. Other Holocene process regimes affecting floodplain morphology have included volcanogenic deltas, tributary fans, dunes, and landslides. Pre-Holocene landforms are locally prominent and include ancient fluvial deposits and bedrock. Historical changes to streamflow regimes, floodplain isolation by flood-control systems, and direct anthropogenic disturbance have resulted in channel narrowing and limited the amount of floodplain that can be shaped by flowing water. Floodplain isolation has caused relative subsidence of tidal floodplains along much of the lower estuary. Most extant landforms are on trajectories controlled by humans and new landforms are mostly created by humans.

Graduation date: 1995

This thesis examines how the construction of news stories reveals relationships among groups of stakeholders and how their views unfold within environmental conflict coverage. This study uses a content analysis of 161 newspaper articles concerning the sea lion and salmon controversy at the Bonneville Dam, focusing on source use and blame and solution frames in environmental conflict coverage. This analysis of articles published between January 2003 and June 2010 in Oregon, Washington, Idaho, California, and Montana contributes to research concerning journalistic norms (i.e., balance and objectivity) and news production routines, specifically within the field of environmental reporting. The findings indicate governmental sources were most frequently quoted and presented the most successful solution frames; while advocacy/non-profit sources were quoted less frequently (in addition to tribal sources) and presented the most blame and failed solution frames. Additionally, this research reflects on the role of news filters, including journalistic norms and legal issues, and explores the relationship between blame frames and failed solution frames, which is perhaps a reflection of the role of spokespeople and media jargon.

Studies of episodic shoreline accretion of the Columbia River Littoral Cell (CRLC) have been ongoing since 1964. In this study, the sediment volumes in the late Holocene barriers and beach plains are compiled and formatted in GIS compatible databases for the four sub-cells of the CRLC. Initial evaluation involved the creation of a geodatabase of 160 dated retreat scarp positions, that were identified on across-shore GPR and borehole profiles. Ten primary timelines were identified throughout the CRLC (0-4700 ybp) and those were used to develop polygon cells. Elevation, distance measurements, and position information were all linked to the polygon through a centroid location within the geodatabase. Once the geodatabase was completed, data was imported into MSAccessTM to create a relational database that would allow for examination of the littoral cell in its entirety or of the individual sub-cells. Within the database, sediment volumes, ages, accretion rates, sediment thicknesses, and timeline relationships were calculated and recorded. Using the database, the accretion history of the Columbia River Littoral Cell was evaluated and this examination illustrated the complexity of the system. Northern littoral transport was shown to be an important factor in the development of the littoral cell as a whole. Total sediment volume in the littoral cell was calculated to be 1.74 x 109 m3, with a mean accretion rate of 1.90 x 104 m3/yr, which is significantly less than some previous studies. This is due to a more detailed analysis of the beach and foredune facies themselves. This is likely the result of the higher precision of beach and foredune surface information using LiDAR. The database shows that the developmental history of the CRLC is dependent on temporal and spatial constraints that can be coupled with reverse modeling to predict shoreline erosion trends from impounded river sediments and potential global sea level rise. The North Beaches and Grayland Plains sub-cells have the greatest potential for future erosion; followed by the Clatsop Plains sub-cell.

In this research a model is developed to predict population for relatively rural areas experiencing rapid economic development. Of the many ways to predict population size, in this research a "demographic-economic" model is chosen for use. The economic variables which aid in projecting population are total employment, and net changes in employment associated with economic growth. The model developed for this research is applied to Oregon's Northern Columbia River Basin Counties of Morrow, Umatilla, and Gilliam. Each county is or is expected to experience rapid growth in its agricultural and/or industrial sectors in the next few years. Using employment projections to the year 1990, population projections are made at five-year intervals between the years 1970 and 1990. / Graduation date: 1977

Graduation date: 1966

Graduation date: 1966

In situ salinity, turbidity and temperature were measured at discrete depths and water samples for radioanalysis were simultaneously collected in the Columbia River Estuary using a specially designed instrument package. Particulate radioactivity was concentrated by filtration and the dissolved radioactivity by evaporation or ferric oxide bulk precipitation. Radioanalysis was by gamma-ray spectrometry and data reduction by computer. Chromium-51 was mostly dissolved and conservative in brackish water, while zinc-65 was mostly particulate and non-conservative. The intrusion of salt water into the estuary was seen to greatly increase the concentrations of particulate chromium-51, zinc-65 and scandium-46 near the bottom. The fall and rise in estuarine radioactivity levels were followed during an infrequent pause in Hanford reactor operations. Changes in radioactivity levels of up to three orders of magnitude were recorded at Astoria, Oregon, some 380 miles from the reactors. The pause in reactor operations enabled the determination of river flow times from the reactors to Astoria. Flow times of 12 and 19 days were measured for average river discharges of 290,000 and 130,000 c.f.s., respectively. / Graduation date: 1967