The Pacific Salmon Treaty was established by Canada and the United States to secure sustainability of salmon harvests within the Pacific Northwest. Renewed in June 1999, the treaty functions to legitimize and empower the Pacific Salmon Commission as the agent of fishery sustainability. The Pacific Salmon Commission serves as a bilateral recommendation-making body. Through its formal and informal, communications, the commission suggests action and defines regional salmon policy. Over the past decade pressures related to overharvest, changing oceanic conditions, and an increasing demand for production have challenged the commission and the fishery as never before. The Pacific Salmon Treaty was officially signed into existence in 1985. It was supposed to be re-ratified in 1992. This did not occur. From 1992 until 1999 numerous ratification processes were attempted, all but one failed. During this time tensions mounted and expressed frustrations nearly prompted overt violence. In August 1997 Canadian fishermen angered at the lack of a solution blockaded a U.S. passenger ferry thrusting the issue onto the world stage. In response to the crisis Canada and the U.S. empowered a joint commission to find resolution. While the resultant Strangway-Ruckelshaus Initiative proved to be a failure, its findings paved the way for eventual re-ratification. The Pacific Salmon Treaty exists because salmon within the Pacific Northwest represent different but simultaneous values within rooted world view orientations. The respective political cultures of Canada and the U.S. have sustained administrative regimes consistent with their dominant understanding of salmon and its values. Divergent cultural expectations and shared economic pressures have sustained conflict over the fishery and led to political and economic uncertainty. The Pacific Salmon Treaty is a work in progress. Understanding the treaty's context, historical development and function is vital for the sustainability of the fishery. The recent ratification of the Pacific Salmon Treaty represents an evolution in shared resource management. Based upon an "abundance-based management" regime the 1999 agreement provides the Pacific Salmon Commission with more discretionary capacity. However, the new pact may prove to be incomplete in form and function because of contradictory world view orientations. This research suggests that an emphasis on struggle management instead of conflict avoidance coupled with an enhanced bilateral commitment to the sustainability of the fishery may prove most helpful for the long-term outlook of the salmon. It also suggests that it is simply too early to tell whether this most recent attempt can or will "save the salmon." / Graduation date: 2001

Genetic differences between early and late forms of Alaskan chinook salmon (Oncorhynchus tshawytscha) were identified using two genetic approaches: mitochondrial DNA (mtDNA) analysis and protein electrophoresis. The study populations consisted of early- and late-run chinook salmon in each of the Kenai and Kasilof rivers in Alaska, and a single population from the Minam River, Oregon, that provided a relative scale for the differences among the Alaskan populations. Two segments of mtDNA were amplified separately using the polymerase chain reaction (PCR) and then digested with 14 to 16 restriction enzymes. Results showed that the two early runs were genetically similar to each other but different from either of the late runs. The late runs were different from each other based on the frequency of the common haplotypes. The Minam River stock shared two haplotypes with the Alaskan stocks and displayed one unique haplotype. The frequency difference in the shared haplotypes together with the presence of a unique haplotype allowed us to separate the Oregon population from those in Alaska. In the protein analysis, each of the five populations was examined at 30 allozyme loci to determine variation within and between the runs. Based on 14 polymorphic loci, Minam River chinook salmon were genetically distinct from the Alaskan populations. Within the Alaskan populations, the two early runs were most similar to each other but different from the two late runs; the two late runs were also genetically most similar to each other. Based on all loci, protein electrophoresis proved to be a useful technique to separate stocks of chinook salmon. On a locus by locus basis, however, mtDNA was more powerful. Both mtDNA and allozyme analysis suggest that chinook salmon may segregate into genetically different early and late forms within a drainage. / Graduation date: 1995

An approach to understanding and managing anadromous salmon, steelhead, and sea-run cutthroat trout (Oncorhynchus spp.) based on life history and evolutionary adaptive capacities of species and stocks is presented. Species, stocks, and local populations are viewed as systems that are continuously adapting to changing environmental conditions. They have the potential capacity to evolve in different ways in different environments through both life history and evolutionary adaptation. Habitat organization forms a template for genus, species, stock, and local population life history organization. Harvesting, habitat alteration resulting from land use practices and other human activities can alter the organization and adaptive capacities of species and stocks, and thus their long term persistence. The adaptive capacity of Oncorhynchus relative to its habitat and management environment is examined at the species, stock, and local population levels. Life history characteristics of representative stocks and local populations are analyzed using Detrended Correspondence Analysis (DECORANA). Fresh water migration distance and latitude are used to "explain" ordination patterns of Oncorhynchus species in the North Pacific Basin. Fresh water migration difficulty and mean annual runoff are used to interpret life history patterns of Columbia Basin chinook salmon stocks. Upstream migration difficulty and fall water temperatures are used to explain the ordination patterns of local populations of Willamette spring chinook salmon. Fishery management practices are examined in terms of their impacts on the organization and adaptive capacity of species, stocks, and local populations of Oncorhynchus. Management generalizations and guidelines derived from the life history theory are applied to management of Willamette spring chinook salmon. Maintaining habitat changes in the Willamette Basin within the historic range of fluctuations will tend to maximize co-organization of local populations. Management activities should provide relatively constant habitat and fishery conditions for natural selection processes to "organize" life history traits over a period of at least a few generations. Fisheries should selectively harvest local populations that show a high degree of realization of their adaptive capacity. By focusing instead on maximizing the co-organization of stocks, their habitat and fishery environments, and protecting the adaptive capacities of stocks, we will go a long way toward providing long-term sustainability for social communities dependent on fisheries. / Graduation date: 1994

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

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 290-299).

Numerous populations of wild Atlantic salmon have declined in recent years. The Atlantic salmon in Girnock Burn, an upland spate tributary of the River Dee, Scotland have been monitored intensely by government scientists since 1966. The burn is equipped with upstream and downstream traps, which have enabled monitoring of juveniles leaving the burn and adults returning to it since 1966. Recently, due to a decline in numbers of female returns, a supportive breeding program was instigated. Using microsatellite-based DNA profiling, this study exploited existing and novel tissue samples to investigate aspects of Atlantic salmon biology and conservation. A panel of up to 12, mainly highly polymorphic, microsatellite loci were employed to derive allele frequency data and to resolve parentage in egg, parr, smolt and anadromous adult samples taken between 1991 and 2004. Genotyping error was investigated and rectified where possible. Overall, the detected error was low (c.0.5%), providing confidence in subsequent population and parentage analyses. The error rate involved in estimating the age of salmon in Girnock Burn from scale readings was also estimated (c.2-8%). A study of the dynamics of natural spawning, based on the parentage of parr, confirmed that multiple matings by anadromous returns of both sexes were prevalent. Not all anadromous returns were apparently successful spawners; data from parr and existing redd samples failed to detect a contribution from 35% of males and 29% of females. An important aspect of the work was to determine the success of the supportive breeding program. Results showed that, in comparison to natural spawning, the program gave a more complete and even representation of adult spawners in offspring. In addition, there was no detectable difference in the output (number of smolts) of the two schemes when the number of eggs used in each was taken into account. The distribution of juvenile kin (parr aged 1+) within the burn was determined, which revealed clustering of full and half sib groups. This was found to impact on standard population genetic analyses. Adjacent samples (n = 50), each sampled over a c.1.5 km stretch of river were shown to exhibit significant allelic differentiation, while samples from individuals selected at random over a 7.5km stretch did not. Parentage analysis of adult returns showed that the number of returns likely to be philopatric was higher than would be predicted solely from physical tagging data. This was attributed to ‘leakage’ of the downstream parr/smolt trap. An initial investigation into the role of mature parr in adaptation of populations to the environment was made, although sire type (i.e. anadromous male or mature parr) was not found to affect survival in the freshwater environment in this case. More research into this aspect is warranted, particularly with the possible impact of predicted climate change on male parr maturity. A comparison of genetic diversity through time (measured by allelic richness) revealed no detectable change between 1991 and 2004. Estimates of the effective population size using different genetic (temporal) methods were associated with a large degree of uncertainty, and were surprisingly high (ranging from 595 to 1992) c.f. demographic based estimates (ranging from 95 to 144), which was likely to be due in part to violation of assumptions made in the calculations. These findings have highlighted a range of avenues for future lines of research, should aid in the management of Atlantic salmon within Girnock Burn and assist in the design of sampling regimes.

Estuarine residence and growth of juvenile chum salmon (Oncorhynchus keta) from Netarts Bay, Oregon were estimated from daily-formed growth increments of sagittal otoliths which are distinguishable from accretion patterns formed during freshwater residence. Estuarine residence time was inversely related to the average size at which juvenile chum salmon entered Netarts Bay. Among fin-clipped, hatchery fish, large individuals disappeared from Netarts Bay more rapidly than smaller members of the same release group during the first 9 days of estuarine residence. This selective removal was not evident among creek-reared chum which were smaller than the fin-clipped fish. Size-related emigration explains this variation in residence time. Growth rates were estimated from back-calculations of fork length from otoliths. The growth rates of juvenile chum salmon in Netarts Bay (0.6 mm FL/d; 3.5% bw/d) were lower than growth rates in other estuaries where harpacticoid copepods were a major prey item. Juvenile chum salmon that entered the estuary early in the spring grew faster than those which entered later in the year, possibly because of lower water temperature and lower density of small (50 mm FL) chum during the early period. High water temperature reduced apparent growth rates by slowing growth and causing emigration of larger, faster-growing individuals. / Graduation date: 1990

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 93-102). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Washington, 1993. / Vita. Includes bibliographical references (leaves [134]-148).

Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 63-68). Also available on the World Wide Web.