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Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fryNoble, Sandra M. (Sandra Marie) 24 January 1991 (has links)
Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and
wild origins were studied in laboratory stream channels and natural
streams. Objectives of the study were to determine if and how earlier
emerging hatchery fry influence the emigration, realized densities,
growth, habitat use, social structure, and activity patterns of
localized populations of wild steelhead fry when the hatchery fry have
a competitive advantage conferred by larger size and prior residence.
During 1986 and 1987, the above variables were observed daily among
hatchery and wild steelhead fry in laboratory stream channels for 8
weeks following emergence in June. The habitat use and social
activities for fry of both origins were observed weekly in natural
stream reaches from June through August in 1987 to corroborate lab
findings. In lab channels, both hatchery and wild fry received 2
treatments: living alone (allopatry) and living together (sympatry).
In the lab, fry of hatchery origin emerged 7 to 10 d prior to wild fry
and remained larger in size during the 8 weeks of study both years.
In natural stream reaches, fry of each origin were observed only in
allopatric situations. Wild fry in the field emerged from natural redds
while hatchery fry were released in stream reaches as unfed, newly
emerged (swim-up) fry.
Hatchery and wild fry in lab sections were found to be very similar
in their emigration rates, distances to nearest neighbor, growth rates,
and use of habitat. Both fry types, regardless of treatment or
environment (lab or field), established similar stable social structure
and used the same types of aggressive acts. Among all lab groups, once
a fry became dominant, it retained that social status to the end of the
study period.
Significant differences (P<.05 both years) among comparison tests
were: 1) in allopatric lab sections, wild fry maintained larger
densities than hatchery fry, 2) in sympatry, hatchery fry had a greater
tendency to establish stable focal points and social hierarchies more
readily, defend larger areas, have better condition, prefer pools with
overhead cover more frequently, be more aggressive, and reach stable
densities more quickly than the wild fry, 3) fewer hatchery fry in
sympatry maintained nomadic positions than wild fry in both treatments,
4) in sympatry, hatchery fry directed more acts of overt aggression
toward wild fry than other hatchery fry, 5) wild fry in sympatry usually
used defensive or less offensive acts of aggression when interacting
with other fry, 6) fry of both origins in natural stream reaches
maintained greater distances to their nearest neighbor than fry in
allopatric lab sections, 7) dominant hatchery fry in both treatments
maintained larger focal areas than subdominant fry, 8) hatchery fry
maintained longer lengths than wild fry through the duration of the
study, and 9) hatchery fry were more aggressive in sympatry than in
allopatry.
Potential differences (P<.05 in one year and P<.1 in the other
year) were: 1) wild fry in sympatry had lower realized densities,
maintained smaller focal areas, had greater proportions of nomadic
individuals, and established stable social hierarchies slower than wild
fry in allopatric lab sections, 2) wild fry in sympatry had poorer
condition than all other fry groups in lab sections, 3) in sympatry,
wild fry were the recipients of the majority of aggressive acts
perpetrated by hatchery fry and other wild fry and usually assumed the
subordinate positions within the social hierarchy, 4) all fry in the lab
showed a high preference for pools with overhead cover and low
preference for gravel and fines and run areas, and 5) wild fry in
allopatric lab sections were more socially active than hatchery fry
while the reverse was observed in the natural streams.
Any influences that could be attributed to inherent differences between stock origins were probably masked by size differences between
fry types. The study would have been more complete had I included
sympatric lab sections where wild fry emerged first and where fry types
emerged simultaneously, and sympatric reaches in natural streams.
Results were further confounded by the limited number of wild adults
used for broodstock in the lab segment of this study. Progeny produced
from so few adults (5 adults of each sex each year) would have very
limited genotypic variation compared to what occurs in natural streams.
This may partially explain why some findings from lab sections and
natural stream reaches differed. Likewise, genotypic expression among
wild fry in lab sections may have varied greatly between years. This
could explain differences found between years in behavior of wild fry
in similar lab treatments.
Although this study does not simulate all possible scenarios,
results support suspicions that introductions of hatchery fry of larger
size and earlier emergence into streams containing wild stocks could
disrupt the social structure and negatively influence the realized
densities, spatial distribution, growth, and behavior of wild juveniles
in recipient streams. / Graduation date: 1991
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Managing adult hatchery summer steelhead for a recreational fishery with reduced hatchery and wild interactions /Schemmel, Eva M. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.
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The value of short run in-stream temperature forecasts : an application to salmonids in the Klamath and John Day Rivers /Huang, Biao. January 2009 (has links)
Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 80-94). Also available on the World Wide Web.
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Metal accumulation in gill epithelium and liver tissue in steelhead (Oncorhynchus mykiss) reared in reclaimed wastewater /Kreye, Melissa M. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2008. / Includes bibliographical references (leaves 50-54). Also available via Humboldt Digital Scholar.
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Born to run? Integrating individual behavior, physiology, and life histories in partially migratory steelhead and rainbow trout (Oncorhynchus mykiss)Sloat, Matthew R. 18 March 2013 (has links)
Steelhead and rainbow trout are common names for marine-migratory (anadromous) and freshwater-resident forms of Oncorhynchus mykiss, a partially migratory salmonid fish. Anadromous and resident forms are sympatric and can produce offspring with a life history different from their own (i.e., steelhead parents can produce rainbow trout offspring and vice versa). The expression of these alternative life histories is a plastic response to individual patterns of energy acquisition, assimilation, and allocation during juvenile life stages. Individual performance during early stream life is of particular interest because of potential carry-over effects on subsequent growth and developmental trajectories. In a series of experiments in laboratory streams, I determined the influence of individual variation in energy metabolism on behavior, growth, and life-history expression in O. mykiss. Individual variation in energy metabolism was a strong predictor of feeding territory acquisition by juvenile fish during the transition from dependence on maternal provisioning of egg yolk reserves to independent feeding. Feeding territory acquisition was positively associated with standard metabolic rate (SMR) under conditions of an abundant and predictable food supply. When the density of intraspecific competitors was manipulated, the association between SMR and territory acquisition was strongest at intermediate stocking densities, moderate at the highest stocking densities, and weakest at the lowest stocking densities. However, reducing the spatial predictability of food resources within streams reversed the influence of SMR on competitive outcomes. These experiments determined that variation in ecological conditions during early life stages imposes different selection regimes on juvenile O. mykiss and results in physiological divergence among cohorts. Subsequent rearing experiments determined that behavioral dominance influences rates of anadromy and freshwater maturation, most likely through the association between SMR and territory acquisition. In addition to the effects of behavioral dominance, I observed a significant influence of sex, rearing temperature, and individual growth trajectories on the expression of anadromy and freshwater maturation. Partially migratory populations of O. mykiss maintain an exceptionally diverse portfolio of life-history strategies. Results from this work lend insight into a suite of behavioral and physiological processes influencing individual life histories. / Graduation date: 2013
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A bioeconomic analysis of altering instream flows anadromous fish production and competing demands for water in the John Day River basin, OregonJohnson, Neal S. 28 July 1987 (has links)
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 of this thesis were to provide preliminary economic data on
the value of instream water in "producing" recreational fishing and to
examine the effect of forestry, agriculture, and livestock practices
on temporal streamflow patterns and anadromous fish production. The
steelhead trout (Salmo gairdneri) sport fishery within the John Day
River basin in north-central Oregon provided the setting for this
research.
The interdisciplinary methodology employed in estimating the
marginal value of water with respect to steelhead production consisted
of two tasks. The first task involved valuing a marginal change in
the quality of the steelhead recreational fishery. The contingent valuation method (CVM) was selected for this purpose. Both open- and
closed-ended willingness-to-pay (WTP) questions were included in a
questionnaire administered to John Day River steelhead anglers during
the 1986/87 steelhead fishing season. Survey data were analyzed to
arrive at individual and aggregate bid functions relating WTP to
expected angling success rates. Results indicate that, under current
conditions, the average angler is willing to pay approximately $7.20
to catch an additional steelhead.
The second task of the instream water valuation methodology was
directed at deriving a streamflow/steelhead production relationship.
By including variables influencing steelhead production in a Ricker
stock-recruitment model, it was possible to develop a model which
could be estimated using linear regression techniques. Some
difficulty arose, however, with interpretation of the model due to the
unavailability of cohort escapement data and the subsequent use of
standing crop data. While possibly masking the true magnitude of
streamflow's effect on fish production, this drawback was not deemed
limiting within the general context of the interdisciplinary
methodology. Results of the biological model conformed to a priori
expectations. Increases in summer and winter streamflows led to
increased steelhead survival, whereas higher spring flows increased
mortality levels. Other results indicate that the John Day Dam was
responsible for a 31.5 percent decline in the population index for the
1969-1983 period.
Combining the economic and biological results into one equation
yielded an estimate of the marginal value of summer instream water in
"producing" recreational steelhead angling. Similar equations were developed for winter and spring flows. The marginal value of water in producing recreational steelhead fishing within the John Day basin was
estimated at $0.56 per acre-foot for summer flows, $0.046 for winter
flows, and -$0.075 for spring flows. By including out-of-basin
benefits, these values increased to $2.26, $0.19, and -$0.30,
respectively. In comparison, water's value in irrigation within the
John Day basin has been estimated at between $10 to $24 per acre-foot.
However, nonuse values of steelhead, as well as the increased
production of other fish species (such as spring chinook salmon) were
not included in the instream water values. In addition, no attempt
was made at valuing instream water's contribution to boating, camping,
or other benefit-producing activities.
A secondary objective of this thesis was to briefly examine the
possible benefits accruing to other instream and out-of-stream users
due to an alteration in streamflow patterns. In addition, the impact
of activities by other resource users -- namely forestry, agriculture,
and livestock production --on anadromous fish production was
reviewed. Improper management practices by these activities can
negatively impact the aquatic and riparian ecosystems. While no firm
conclusions were drawn, it appears the quality of these ecosystems, as
opposed to the amount of streamflow, has the largest marginal impact
on anadromous fish populations. / Graduation date: 1988
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Long-term effects of habitat and management changes on steelhead production: results from an individual-based modelBolduc, Melanie B 04 May 2006 (has links)
Steelhead populations support an economically valuable fishery in the Great Lakes region. Development of the region, resulting in land use changes and the introduction of hydropower, has affected the riverine habitat used by steelhead. I have developed an individual-based model of steelhead in the Manistee River, Michigan that simulates the long-term production of steelhead from the river. The model begins each year with a spawning population that produces redds for that year and then follows the offspring from each redd as individuals until they smolt one, two, or three years after spawning. Simulations run for ten-year periods. The simulated individuals are subjected to mortality from predation, starvation, and temperature extremes. Predation is a length-based mortality and is thereby affected by growth. Growth is determined by an individual's foraging success and bioenergetics. I conducted simulation experiments to examine the effect of changes in spawning numbers, temperature, and flow regime, on the number of individuals smolting in the river each year. Simulations reveal that the current flow regime and colder water temperatures are most beneficial for steelhead production and increasing the number of spawners does not increase steelhead production. The results also suggest that the young-of-the-year (YOY) stages have the greatest impact on steelhead production because the model showed no indication that steelhead life stages older than the YOY could compensate for density-related losses that occurred during the first year.
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Gene Expression Life History Markers in a Hatchery and a Wild Population of Young-of-the-Year Oncorhynchus mykissGarrett, Ian D. F. 20 September 2013 (has links)
Life history within a single species can vary significantly. Many of these differences are associated with varying environmental conditions. Understanding what environmental conditions cue alternate life histories within a single species has been researched extensively. In salmonid fishes, more than almost any other group, varying environmental conditions give rise to individuals within species that take markedly different life history trajectories.
Oncorhynchus mykissis a species of salmonid native to the Pacific Northwest region of North America. This species has two life history forms, anadromous and resident. The anadromous form spends a portion of its life in ocean while the resident life history form completes its entire life history in freshwater. Until the decision to migrate and morphological changes associated with smoltification occur, the two life history variants of this species are indistinguishable from each other. This ambiguity in juvenile O. mykiss morphology presents challenges for conservation managers charged with protecting and increasing threatened O. mykiss populations around the Pacific Northwest because conservation efforts cannot be evaluated until juvenile fish make the decision to migrate.
Microarray gene expression analysis was used to profile gene expression in juvenile populations of wild and hatchery O. mykiss to identify gene expression variation associated with alternate life history variants. This analysis identified 8 DNA sequences present in both brain and gill tissues that differ in expression in rainbow trout and steelhead hatchery stocks. Differential expression as quantified by microarrays was validated with quantitative real-time PCR. Lastly, the expression of these putative life history markers was preliminarily evaluated in a wild population of O. mykiss at sample locations in the South Fork John Day River Basin, Oregon with known ratios of juvenile anadromous and resident fish.
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"In common with all citizens" : sportsmen, Indians, fish, and conservation in Oregon and Washington /Rawson, Timothy Mark, January 2002 (has links)
Thesis (Ph. D.)--University of Oregon, 2002. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 330-363). Also available for download via the World Wide Web; free to University of Oregon users.
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Predatation by hatchery steelhead on natural salmon fry in the Upper-Trinity River, California /Naman, Seth W. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2008. / Includes bibliographical references (leaves 58-66). Also available via Humboldt Digital Scholar.
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