Habitats for juvenile chinook salmon (Oncorhynchus tshawytscha) were
observed at a high flow during the spring of 1989 and at a low flow during the
spring of 1991 in the lower American River of California. Parameters of
microhabitats in eight macrohabitats were measured. Mean column water velocity
and total water...
Redband trout density was examined in three forested streams in central
Oregon at two scales, pool channel unit and microhabitat. Two streams were in
roadless areas and one was in a "highly managed" watershed. At the larger
spatial scale, trout displayed a seasonal shift in habitat use from early to...
Rainbow trout (Salmo gairdneri) and bluegill (Lepomis macrochirus)
were exposed to flows of water containing low DO concentrations
produced by bubbling nitrogen through the water. Abrupt exposure of
fish to critical DO concentrations (The standard dose response) and by
a more gradual changing of DO levels (The "stepdown" approach) were...
The growth and production of brown trout, Salmo trutta Linnaeus, exposed to a concentration of 0.65 mg/l BOD (4.1 percent by volume) stabilized kraft mill effluent (KME) were studied from October 1973 until May 1974 in three experimental stream channels located near a kraft mill in Albany, Oregon. Growth rate...
Predator-prey interactions, as measured by the consumption
and growth rates of a predator (Micropterus salmoides) and by the
observed activities of both predator and prey (Gambusia affinis),
were found to be sensitive to sublethal levels of ammonium chloride
(reported as unionized ammonia NH₃).
One bass and 15, 30, 60 or...
Sixteen populations of guppies (Poecilia reticulata) were established
in laboratory aquariums. Eight populations were exposed to
dieldrin at a mean concentration of 0.525 ppb in the water and 2.11
ppm in the food, tubificid worms. Eight populations received control
water and food. All populations were fed three grams of tubificid...
A series of log storage experiments were conducted to determine
whether leachates derived from water storage of logs are acutely
toxic to fish. Log segments approximately 18 inches long and 16 inches
in diameter were stored in tanks and held submerged for a period of
7 days. The holding water...
A laboratory investigation was performed to determine the influence of 2,4-dichlorophenol on the flavor of fish. The study was conducted at the Oak Creek Fisheries Laboratory of the Department of Fisheries and Wildlife, Oregon State University. The three experimental apparatus used in this study were designed to deliver 250 ml/min...
Water treatments were applied to young ponderosa pine trees in the Eastern Cascades, Oregon during the 2003 growing season, and shade treatments were applied during the 2003 and 2004 growing seasons to understand how photosynthesis and soil respiration, particularly the root/rhizosphere fraction (R[subscript rrh]), would respond to increased moisture availability...
To begin to understand freshwater seasonal floodplain fish communities in the context of human alteration of the physical system, species introductions and wetland restoration efforts, I studied fish assemblages in fifteen seasonal floodplain wetlands within four geographic regions (coastal, upper Columbia River estuary, Puget Sound and eastern Oregon/Washington) in the...
Water availability is a critical limiting element in semi-arid ecosystem productivity and presents particular challenges in Sahelian countries such as Senegal. The landscapes are characterized by the presence of two common semi-arid shrubs (Piliostigma reticulatum and Guiera senegalensis), both of which may be important hydraulic regulators in these water-limited ecosystems....
Discrete coldwater patches within warm streams provide potential thermal refuge for coldwater fishes during periods of heat stress. This analysis focused on heterogeneity in stream water temperatures as influenced by local influx of cooler subsurface waters. Using field thermal probes and recording thermistors, we identified and characterized coldwater patches potentially...
We examined long-term changes in daily streamflow associated with forestry practices with two datasets (this one and the original Alsea Streamflow dataset (1972) over a 60-year period (1959–2017) in the Alsea Watershed Study, Oregon Coast Range, Pacific Northwest, USA. In this contemporary period, 2006 to 2017 (12 water years), data...
The lower Deschutes River of northcentral Oregon has a historically uniform discharge record. Significant reductions in discharge below the seasonal norms will degrade the environment for migratory and resident salmonids by increasing siltation and gravel compaction, and by reducing intragravel water dissolved oxygen content. Fish spawning will be limited by...
Population size of Clavibacter michiganensis subsp.
sepedonicus in potato cv Russet Burbank and plant response
as affected by drought were assessed in a greenhouse
experiment. Water deficit stress and no stress treatments,
and inoculum densities of 0 or 2 X 10⁷ cfu C. m.
sepedonicus/seed piece were arranged factorially. Stem...
In a field study, seedlings of Arizona pine (Pinus arizonica Engeim.), Apache pine (P. engelmannii Cam), and Durango pine (P. durangensis Mart.) were planted in an one open area and in canopy gaps of four forested sites of a pine-oak forest in the Sierra Madre Occidental in the state of...
An investigation of the fishes of the Willamette River and three of its larger tributaries was made during July, August, September, and November of 1951, to ascertain the possibility of using them as bio-indices of pollution. Thirteen stations were established on the Willamette River and tributaries. These stations were selected...
The growing demand for water in the arid regions of the West
increases the need for optimal allocation of water among competing
uses. An efficient allocation of water between instream and out-of-stream
uses has been impeded by institutional constraints and the
scarcity of information regarding instream flow benefits. The
objectives...
I studied the water relations traits, twig conductivity, C'3 isotopic composition,
and wood density of three conifer and five angiosperm species in western Oregon. This
study took place from spring 2002 to fall 2003 on four sites. Species were selected to
represent the diversity of drought tolerance of woody plants...
Concentrations of twenty-five PCBs, fifteen organochiorine pesticides and mercury were determined in recreational fish from the Willamette River, Oregon during the summer of 2000. Thirty-six fish samples of three fish species including black crappie, smalimouth bass and con-rn-ion carp were analyzed. The data reported here provides new information and recent...
Previous studies have shown that rainbow trout exposed to dieldrin via diet for 9 to 12 weeks increased biliary excretion of a subsequent dose of [¹⁴C]dieldrin by 500%. This was not explained by induction of the cytochrome P-450 (CYP) system involved in oxidative metabolism of these compounds. We hypothesized that...
Riparian areas in the arid western United States are critical ecosystems that have been severely degraded by a variety of land and water uses over the last 100 years. In this study, the composition and structure of floodplain vegetation along the Lower Owens River in eastern California was quantitatively described...
I tested the hypothesis that there is a correlation between inundation period and net primary production (NPP) in estuarine salt marshes through an observational experiment at South Slough National Estuarine Reserve, Oregon. I estimated primary production and inundation period for selected monotypic plant communities in (1) a naturally restored wetland...
For oysters, "The objective of these studies was to determine the biological feasibility of using the heated effluent from coastal nuclear power plants for culturing the Pacific oyster, Crassostrea gigas." (p.1) Work included oyster growth experiments, seasonal growth experiments and closed system studies. For salmon, "The objective of these studies...
Water temperature influenced interactions between redside
shiners and juvenile steelhead trout (≥1+) in the field and the
laboratory. Distribution of the two species within various habitats
was determined in three streams with different water temperature
regimes. The range of habitats occupied by trout in allopatry at
cool temperatures and at...
Rivers impacted by human activities often have multiple stressors present. The effects of multiple stressors on biological communities can often be difficult to predict, due to the potential for complex interactions between stressors and communities. This thesis explores the impacts of two stressors often associated with agricultural land use, increased...
A symposium presented before a joint meeting of the
American Society of Ichthyologists and Herpetologists
and the Western Society of Naturalists at Stanford University
on June 29, 1939, and published as a special issue
of the Stanford Ichthyological Bulletin through the cooperation
of the Fish Commission of the State of...
Field investigations were implemented to study the interrelationships between streamflows and salmonid production during the summer-fall low flow period in two natural stream channels. Elk Creek, near Cannon Beach in Clatsop County, was the site selected for intensive investigation.
Construction of streamflow control and diversion facilities was completed in November...
This report presents data collected during the first full field season of
a project designed to examine the streamflow requirements of juvenile salmonids. Problems encountered in the original design, changes made in the design and the application of the expected results are discussed.
I used current water management practices in central and eastern Oregon and Washington as natural experiments to quantify the effects of irrigation water withdrawals on macroinvertebrate community structure and life history strategies. Reduced discharge had direct (e.g. decreased velocity and wetted habitat) and indirect (e.g. increased conductivity and temperature) effects...
Two separate studies were conducted during this research
project. Oysters were irradiated with 500 and 1000 rads and 5, 10,
20, 50, 75, 100, 150, and 200 krads in the first study in order to
determine the effects of ionizing radiation on survival and growth
rates. Two periods of high...
Many environmental factors influence cardiovascular and
respiratory activities of crustaceans. The effects of natural
stressors (hypoxia, low salinity, high temperature) have been well
studied, but the effects of pollutants upon these two organ systems
have received less attention. The presence of the pesticide
carbaryl (Sevin, Union Carbide, Inc.) and its...
The effects of exposure to suspended silt, kaolin and fuller's
earth on growth and condition of Pacific oysters, 16 months of age,
were studied. The exposure apparatus maintained a continuous flow
of turbid water through chambers containing test oysters. Additional
studies measured the filtration rates of oysters exposed to suspended...
The Washington Cooperative Fishery Unit at the College of Fisheries, University of Washington, Is carrying on studies of fishes in Lake Washington as part of the International Biological Program sponsored by
the National Science Foundation. One of our interests Is. in the effects of temperature on the movements of fishes...
Until the 1930s, flows of the Colorado River maintained approximately 781,060 hectares of wetlands in its delta. These wetlands provided important feeding and nesting grounds for resident and migratory birds as well as spawning and protection habitat for many fish and other invertebrate species. However, the Delta's wetlands started to...
Although it is generally assumed that the intensifying abiotic environment is the primary effect of drought on aquatic organisms, drought-induced top predator extinctions may be an important underlying mechanism. I used manipulative experiments to disentangle the impacts of drying and top predator extinctions on arid-land aquatic invertebrate communities. I then...
During spring and early summer hydropower projects are often forced to spill water through their spillways due to increased river flows of the runoff season. Flows which are directed through spillways--instead of through turbines--contain a substantial amount of energy. Stemming from the high energy content, spillway flows entrain air at...
This annotated bibliography was compiled to provide forest managers with a comprehensive list of sources on the potential effects of silvicultural activities on wildlife and fish populations in Pacific Northwest forests. The bibliography emphasizes publications directly examining silvicultural activities and responses by these populations. Abstracts from 296 publications are indexed...