The movements of a population of adult sockeye salmon
(Oncorhynchus nerka) were followed in a small tributary of Brooks
Lake, Alaska until spawning was nearly complete in 1963. The objectives
of the study were to describe the movements of sockeye
salmon on the spawning ground of an entire small stream,...
The experiment was conducted at the Soap Creek farm ponds
near Corvallis, Oregon. Oregon Moist Pellet and Purina Trout
Chow at three different rates of feeding for each diet were used
to feed fingerling channel catfish stocked at the rate of 1,000 per
acre. A complete random design and Fisher's...
The effects of a sublethal concentration of dieldrin (0. 2 ppb)
in the water on the growth and body composition of underyearling rainbow
and cutthroat trout held in aquaria and fed different rations of tubificid
worms or Oregon moist pellets were studied at Oak Creek Fisheries
Research Laboratory, Oregon State...
A theoretical framework for economic fishery management was
developed. Extensive isocline analysis of a general fishery model
yielded a detailed look at the possible equilibrium behavior of a
system that was allowed to vary in terms of the levels of its
environmental parameters, its composition, and the response functions
governing...
Selected life history aspects of American shad, Alosa
sapidissima, collected in Lake Umatilla of the Columbia River
during 1980 and 1981 were examined and compared to other shad
populations. Mean fork lengths of adult shad captured in
1981 were 405-, 415- and 423-mm for age III, IV and V males;...
The goal of this study was to better understand stream communities through a perspective that might make their structure, organization, and development more understandable. This goal was approached
through the following objectives:
1. To determine the assemblages of stream organisms and define subsystems within a stream community.
2. To explain...
Two replications of a half dial lei cross experiment were performed among four inbred lines of mosquitofish, Gambusia affinis.
These inbred lines originated from three random-bred stocks: OR,
TX and CD. The experiment was conducted as a completely randomized
design. Experimental material consisted of parental lines and F₁ populations maintained...
The sample ratio of sublegal to legal male crabs retained in crab
pots was used in calculations to predict future harvest of Dungeness
crabs, Cancer magister, along the Oregon coast. Accurate predictions
by this method require a sample ratio representative of the population
ratio. I sampled the Oregon Dungeness crab...
Samples of weathervane scallops taken on Oregon Department of
Fish and Wildlife cruises off Oregon waters during 1981-1982 were
analyzed for a comparative growth study. No evidence of internal
growth marks were found in the shell structure when analyzed by the
acetate peel technique. Internal growth lines formed in the...
Factors that influenced the uptake, storage, and elimination of dietary quinoline by rainbow trout (Salmo gairdneri) were studied to obtain an understanding of the mechanisms affecting the bioaccumulation of dietary contaminants in teleosts. Rainbow trout readily absorbed ¹⁴C-quinoline from pelleted food (1% ration at 138 ug quinoline/g food) and most...
The morphology and ecological importance of habitats associated with the margin of third-order stream channels in the Oregon Cascades were studied in streams in three different riparian types: 450-year-old conifers, 40-year-old alder, and an open, herbaceous-dominated clearcut. Margins, backwaters, and side channels in streams create important habitat for fry of...
A comparative analysis of structures related to
capture and processing of food, in 624 specimens belonging
to 31 species of Sebastes of Oregon was made. The
structures studied were the following: the tooth-bearing
bones (premaxillary, dentary, vomer, palatine); the
maxillary, angular, articular, parasphenoid and glossohyal
bones; the lower limb of...
The abundance and biomass of cutthroat trout (Salmo clarki) have
been found to be greater in logged than in forested streams of the
Oregon Cascades. Although certain prey taxa increase in abundance
following logging, habitat stability generally decreases and cover
structures are removed. Research was conducted to examine the manner...
A generalized mathematical model of ecosystems is
developed. The model begins with the general class of
systems known as state-determined systems, in which the
time-derivative of each state variable is a function of some
subset of the set of all system state variables and
.environmental parameters. A formal basis is...
An analysis was conducted to estimate the minimum mesh
size for managing the common Chilean hake (Merluccius gayi)
fishery. Secondary objectives were to establish the
selective relationship between mesh size and fish length,
to examine growth patterns and related parameters, and to
estimate the critical age (or optimum size) at...
Seasonal habitat availability, utilization, and selection by young
of the year (< 25 mm) and adult (>25 mm) redside shiner, Richardsonius
balteatus, were studied for 1 year in sections of Greasy Creek, Benton
County, Oregon. Intensive stream mapping procedures and snorkling
observations provided most of the quantitative measures for habitat...
Natural and gabion modified habitats containing coho salmon
(Oncorhynchus kisutch) were observed and measured seasonally in East
Fork Lobster Creek, a fifth order stream in western Oregon. Coho
salmon usually inhabited backwater and secondary channel pools in
winter. Large wood debris complexes and undercut banks were the
primary sources of...
A framework is presented for a more causal explanation and ordering of stream characteristics than traditional means have used. Patterns of stream habitat distribution are related to particular characteristics of the geomorphology of watersheds. Variability in stream characteristics can be explained by the spatial distribution of properties of the watershed...
To understand the influence of selective harvesting on
the adaptive capacity of fish populations in changing
environments, a computer simulation model was developed. In
the model, hypothetical populations were composed of five
different life histories, which were genetically determined.
Each life history type had its own rate of survival and...
The abundance of the 1982 brood of juvenile coho salmon
(Oncorhynchus kisutch) was determined in August 1983, and January
and April 1984 at 20 study sites spread throughout Knowles Creek,
an Oregon coastal watershed. The timing of emigration of juvenile
coho from the watershed was monitored from October 1983
through...
In higher vertebrates, normal digestion and absorption by the
gastrointestinal tract are dependent on the orderly and controlled
transit of intraluminal contents. A relationship between fluid
passage through the gut and absorption from the gut has yet to be
examined in fish. In marine teleosts, the osmolality and ion concentration...
Juvenile English sole (Parophrys vetulus) were
collected in Yaquina Bay, Oregon from January, 1986 to
March, 1987. Recruitment of young-of-the-year sole
occurred from January to June, 1986 and again from
December, 1986 to February, 1987. Emigration from Yaquina
Bay started in September, 1986, but a small portion of the
English...
Many resource management controversies indicate
disagreement about the possible intended and unintended effects
of management actions on ecosystems. Researchers have
documented a variety of negative effects on specific ecosystems, e.
g. the degradation of salmonid habitat due to mass wasting
(Hagans et al. 1986). While the effects of some management...
Nine isolates of bacteria recovered from fish dying at
marine facilities were collected from different geographic areas.
The strains included: an isolate from chinook salmon (Oncorhynchus
tshawytscha) reared in net pens in New Zealand, an isolate
from chum salmon (Oncorhynchus keta) held at a laboratory in
Oregon, USA., and seven...
Crosses were made between a stock of summer steelhead (Salmo
gairdneri) known to be resistant to infection by Ceratomyxa
shasta and stocks of summer steelhead known to be susceptible.
Ceratomyxosis, the disease caused by C. shasta was initiated by
exposure to Willamette River water. I found that the crosses
were...
Once historically widespread throughout the Willamette and Umpqua
River drainages, the Willamette Oregon chub is now restricted to
scattered populations along 15 miles of the Middle Fork of the
Willamette River whereas the Umpqua Oregon chub is still widely
distributed. The decline in the Willamette drainage was more severe
because...
This study was an investigation to determine the distribution, abundance and general food habits of salmonids and non-game fishes residing in several selected coastal streams, Douglas and Coos Counties, Oregon. The physical conditions that characterize the various stream habitat types were monitored and the influence of physical conditions on the...
Juvenile fall chinook salmon were acclimated to full strength sea water at 66, 73, and 80 days after hatching. Survival in sea water for 14 days was used as the criterion for successful acclimation. The growth of salmon acclimated to sea water was slower over the period of observation (134...
Variation in growth rate of Dover sole (Microstomous pacificus) off Astoria and Brookings, and English sole (Parophrys vetulus) growth off Astoria and Coos Bay, Oregon was studied using the distance between annuli on scales and interoperculum bones indicating growth rate for Dover sole
and English sole respectively. The age at...
This study¹ was undertaken: (1) to obtain information on the distribution of the snail, Oxytrema silicula, in three coastal rivers in Oregon, and the seasonal incidence of infection in these snails and in snails from an inland stream, with the cercariae of the trematode, Nanophyetus salinincola; (2) to follow cercarial...
The distribution of adult Pacific herring (Clupea harengue
pallasi) near Auke Bay, Lynn Canal, southeastern Alaska, varied by
depth and geographic area over 24 successive months during 1973-75.
From June through September, schools concentrated at 5- to 37-m
depths where zooplankton was abundant, and moderate currents were
present in a...
The merits of fertilizing warmwater fish ponds with dry organic manure were studied from October, 1964 to November, 1965 using two experimental ponds in the Willamette Valley. One pond (pond II) was fertilized with urea and single superphosphate and the other (pond III) was fertilized with dried manure as well...
Classification of Streams and stream habitats is useful for research involving establishment of monitoring stations, determining local impacts of land use practices, generalization from site-specific data, and assessment of basin-wide, cumulative impacts of human activities on streams and their biota. This thesis presents a framework for a hierarchical classification system,...
English sole is a major contributor to Oregon and Washington groundfish resources. In accordance with the continued trend of increasing fishing effort, in 1975 Oregon State University Sea Grant
funded an extensive groundfish research program: the Pleuronectid Project. The purpose was to provide information to assist resource management agencies. This...
The osmoregulatory capabilities and tolerance of Kelp greenling, Hexagrammos decagramrnus, were studied in a series of seven salinities ranging from fresh water to concentrated sea water of 50 ppt. Results indicated that they were tolerant over a wide range of salinities but were incapable of surviving below 5 ppt and...
Genetic, ontogenetic, and environmental factors modified characteristic interrenal and glycemic responses to stress in juvenile salmonid fishes. During continuous confinement stress, plasma cortisol rose more quickly in chinook salmon, Oncorhynchus tshawytscha, acclimated to high rather than medium or low temperatures; hyperglycemia following either acute or chronic stress was also highest...
Hypotheses of phylogenetic and historical zoogeographic relationships of glyptocephalines (Glyptocephalus cynoglossus, G. zachirus, G. stelleri, Microstomus kitt, H. pacificus, H. achne,
Embassichthys bathybius, and Tanakius kitaharae) were constructed based on comparative anatomy and external morphology. The phylogenetic approach was cladistic and character polarity was
determined by using out-group comparison. One...
Numerous tests were applied to rainbow trout
of eleven months of age to determine whether
ascorbic acid is an essential element of the diet
of these fish. Although previous work had been
done on this question, conflicts in the results,
the large reliance upon abnormal symptoms such as
lordosis and...
The taxonomic placement of Gadopsidae is discussed and an evaluation of its osteological relationships with related families is given. Similarities to the more primitive genera of the trachinoids, notothenioids, and uranoscopoids are noted and the inclusion of Gadopsidae in the Trachinoidae is recommended. A description of the geological history of...
Several types of instream structures were evaluated for their
potential to provide rearing habitat and to increase reach carrying
capacity for steelhead trout (Salmo gairdneri). Evaluation was
conducted in each season over the course of 1 year.
Blast pools created in bedrock glides increased the carrying
capacity of stream reaches...
Regions of similar species composition and groups of demersal fish
species with similar distribution patterns from Cape Flattery,
Washington to Point Hueneme from 50-250 fm (93-460 rn) were defined based
on results of an agglomerative cluster analysis of National Marine
Fisheries Service Rockfish Survey data taken during the summer of...
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...
Seventeen populations of Gila Baird and Girard are identified from the Alvord Basin of southeastern Oregon and northwestern Nevada. Gila in the Alvord Basin occupy a wide range of habitats, including warm springs, cool springs, creeks, reservoirs, and a thermal lake. These populations became isolated in remnant habitats when waters...
A theory of the origin and distribution of fishes in the Harney Basin is presented. Blitzen River, the hydrographically and ecologically isolated creeks, and the upland tributaries of Silvies River all contain populations derived from the basin's Pleistocene connection with Malheur River of the Snake system. Colonization of many streams...
Production, food consumption and food habits by groups of small, mixed and large sizes of cutthroat trout were studied in enriched and unenriched sections of the Berry Creek Experimental Stream, Oregon State University. Continuous introduction of sucrose and urea to portions of the stream resulted in heavy growth of Sphaerotilus...
Aquatic communities consisting of guppies, amphipods, copepods, snails, nematodes, rotifers, protozoans, euglenoid flagellates, and other microorganisms were established in sixteen laboratory microcosms. Guppies were exploited at four different levels (0 percent, 10 percent, 20 percent, and 40 percent of the population biomass) with four communities at each level of exploitation....
The effects of two patterns of logging on the intragravel environment were studied in three Oregon coastal streams between June 1968 and June 1969. The watershed of one stream (Needle Branch) had been clearcut, and that of a second stream (Deer Creek) cut in staggered settings in 1966. A third...
The behavior of two species of stream salmonids, juvenile coho salmon, Oncorhynchus kisutch (Walbaurn) and cutthroat trout, Salmo clarki clarki Richardson, was studied in terms of the time spent by individual fish in carrying out various activities. Studies were conducted from June 1968, through May 1969, at Berry Creek, a...
Organization and the adaptation of aquatic laboratory ecosystems
to resource availability, exploitation, and a toxicant were examined in
a 34-month study. Sixteen 560-liter microcosms including prey,
predator, and competitor populations were employed over a wide range
of energy and habitat resource availability and exploitation of the top
predator. Chronic exposure...
Adequate management and scientific investigation of ecosystems
depends on classification of landscape systems based on all significant
bio-physical and associated cultural properties. The present
classification is a hierarchical systems design that can be modeled in
terms of a natural system interacting with its level-specific
environment. A watershed system in this...
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...
The effects of temperature, temperature fluctuation, and fish size on the growth of juvenile steelhead trout (Salmo gairdneri) were studied in experiments which lasted 10 to 25 days. Groups of fish were fed at ration levels varying from near-starvation to repletion. Decelerating, curvilinear relationships between rates of food consumption and...
The nature of the interaction between juvenile coho salmon, Oncorhynchus kisutch (Walbaum), and fall chinook salmon, 0. tshawytscha (Walbaum), was studied in Sixes River, Oregon. Seining, snorkeling, and tagging were used to determine distribution and patterns of growth of these two species in the stream environment. Experiments conducted in flowing-water...
A study of the effects of stabilized and unstabilized kraft mill effluents on the production of chinook salmon (Oncorhynchus tshawytscha) in six laboratory streams was conducted at the Pacific Cooperative Water Pollution Laboratories, Oregon State University-from May through August, 1969. Similar salmon biomasses were stocked in each stream. Changes in...
Periodic determinations of plasma hormone levels suggested that changes in interrenal activity are unrelated to changes in thyroidal or gonadal activity during development (smoltification) of juvenile coho salmon (Oncorhynchus kisutch). Moreover, in an experiment where fish were reared under various conditions of crowding and water inflow rate, it appeared that...
Based on the number of velar tentacles and the form of longitudinal
lingual laminae found in Lampetra (Entosphenus) t. tridentata
and its closely related forms, the taxon Entosphenus should not be
considered as a genus as commonly adopted, but, along with the taxa
Lethenteron and Lampetra, should be regarded as...
Acute toxicity bioassays and growth studies, with juvenile salmon
as test animals, were used to identify and characterize the major
toxic components of a zirconium process effluent (ZPE) produced by
Teledyne Wah Chang Albany Corporation.
The major toxic component of the ZPE is ammonia. Although
other components of the ZPE...
A study was conducted at the Pacific Cooperative Water Pollution
and Fisheries Research Laboratories, Oregon State University,
to determine the effects of pentachlorophenol (PCP) on the early developmental
stages of the steelhead trout (Salmo gairdneri). Experiments
were performed from May, 1965, through May, 1968, on the
survival, growth, and bioenergetics...
Ninety-six hour acute toxicity bioassays were employed to
determine the tolerance of juvenile coho salmon to chlorinated
stabilized kraft mill effluent (SKME). In addition the effect of
chlorinated SKME on the growth of juvenile coho salmon in six and
ten day experiments was studied.
Results of the acute toxicity tests...
A reliable, easy, and inexpensive method for determination of
molecular hydrocyanic acid (HCN) in solutions of simple and complex
metal cyanides is described. The method was used to determine
molecular HCN concentrations as low as 0.005 milligram per liter,
and can be used for determination of even lower levels. It...
Recreational angling pressure has recently increased in the neritic
reef areas off the central Oregon coast. This study describes
weight-length and age-length relationships as well as ages at sexual
maturity of the black, blue, canary, yelloweye, and yellowtail rockfish
(Sebastes melanops, S. mystinus, S. pinniger, S. ruberrimus, and
S. flavidus,...
Acute toxicity bioassays (96-hr TL₅₀) were employed to determine
the tolerance of coho salmon (Oncorhynchus kisutch) to inorganic
chloramines at the alevin (yolk sac fry), yolk absorption, and early
juvenile life stages. Any influence of changes in temperature, pH,
and total alkalinity on the tolerance of juvenile coho for chloramines...
A tagging study was conducted from June 1978 through January 1982
to provide information on the movements of adult neritic reef fishes
off the central Oregon coast. To evaluate the cause of low tag
returns of previous tagging studies of reef fish in this area, tag
retention, post-tagging mortality, and...
Growth characteristics of otoliths were used to determine age, and to separate known races and stocks of steelhead trout (Salmo
gairdneri). Otoliths were the first calcified structures observed in X-ray photographs of steelhead embryos, and a continuous record of events through life was interpreted from these structures. A direct
relationship...
This research was conducted on the life history of the blue
chub, Gila (Gila) coerulea (Girard), inhabiting Paulina Lake, Oregon,
and the tui chub, Gila (Siphateles) bicolor (Girard), East
Lake, Oregon. The results are applied to the fisheries management
of these lakes. Both species are endemic to the Klamath River...
The effects of sublethal concentrations of cyanide, pentachlorophenol and zinc individually and in combination on the growth and production of juvenile chinook salmon, Oncorhynchus tshawytscha (Walbaum), and aquatic invertebrates in model stream communities were studied in three experiments during 1971 and 1972 at the Oak Creek Fisheries Research Laboratory, Oregon...
In the fall and winter of 1965, 1966, and 1967, 298 ratfish (180 males, 118 females) were collected off the Pacific coast of
Oregon and Washington and examined for food habits , parasites, growth relationships and a method of age determination. The following
food organisms were found to be the...
This study was designed to provide life history information about juvenile fall Chinook salmon, Oncorhynchus tshawytscha
(Walbaum), in a small coastal river by 1) documenting the length of residence of the juveniles throughout the river, 2) exploring several factors possibly influencing their length of residence, and 3) assessing the relative...