Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (leaves 198-219).

Thesis (M.A.) - Simon Fraser University, 2005. / Theses (Dept. of Archaeology) / Simon Fraser University. Also issued in digital format and available on the World Wide Web.

This thesis examines J. H. Todd & Sons Ltd., a British Columbia family-owned and run fish packing company during the years 1881 through 1954. The research presented in this paper outlines the contribution of individual Todd family members to both the success and eventual demise of the company. Also examined is the history of the B. C. salmon canning industry, the evolution of J. H. Todd & Sons Ltd., the role of the company in the broader context of the B. C. fishing industry; and the factors that led to the demise of the company. This thesis relies on documentary primary sources as well as an extensive oral history collection obtained from Todd family members and employees. / Graduate / 0334 / 0509 / 0510 / micfitz@shaw.ca

Recent years have seen considerable advances in the study of biological rhythms and the underlying molecular mechanisms that drive the daily and seasonal physiology of vertebrates. Amongst teleosts the majority of work in this field has focused on the model species the zebrafish to characterise clock genes and the molecular feedback loop that underpins circadian rhythms and physiology. Daily profiles of clock gene expression in a wide variety of tissues and cell types are now relatively well described. However the zebrafish is a tropical species that does not display distinct seasonality and therefore may not be the species of choice to investigate the entrainment of circannual physiology. In contrast, Atlantic salmon is a highly seasonal teleost that displays considerable temporal organisation of most physiological processes. In salmonids photoperiod is widely known to synchronise physiology to the environmental conditions and as such photoperiod manipulation is routinely used by the salmon industry throughout the production cycle to control and manipulate spawning, smoltification and puberty. Previous studies in salmonid species have already identified a set of clock genes that are linked to these seasonal physiological processes. However, to date, the molecular mechanisms regulating daily and seasonal physiology are largely unknown despite the strong commercial relevance in the Atlantic salmon. In the Atlantic salmon, Davie et al (2009) was the first to report the photoperiod dependent circadian expression of clock genes (Clock, Bmal and Per2 and Cry2) in the brain of the Atlantic salmon. In the same investigation the expression of clock genes was reported in a wide variety of peripheral tissues, however 24h profiles of expression in peripheral tissues were not characterised. In order to examine further the role of seasonal photoperiod on the circadian expression of clock genes, the present work first aimed to characterise diel profiles of Clock, Per1 and Per 2 expression in the brain together with plasma melatonin levels in II Atlantic salmon acclimated to either long day (LD), short day (SD), 12L:12D (referred to as experiment 1 throughout) and SNP (referred to as experiment 2 throughout). Photoperiod dependent clocks were also investigated in peripheral tissues, namely in the fin and liver. Results showed circadian profiles of melatonin under all photoperiods. In experiment 1 both Clock and Per2 displayed significant circadian expression in fish exposed to LD. This is in contrast to previous results where rhythmic clock gene expression was observed under SD. In addition, clock gene expression differed in response to experimental photoperiod in the liver, and diel rhythm differed to that of the brain. No rhythmic expression was observed in the fin. Levels of plasma melatonin exhibited a circadian rhythm peaking during the nocturnal phase as expected. However the amplitude of nocturnal melatonin was significantly elevated under LD (experiment 1) and the SNP long day photoperiod and 2010 autumnal equinox samples (experiment 2). Overall results from these experiments suggested that the control of clock gene expression would be photoperiod dependent in the brain and the liver however photoperiod history is also likely to influence clock gene expression. Interestingly, the gradual seasonal changes in photoperiod under SNP did not elicit similar profiles of clock gene expression as compared to experimental seasonal photoperiods and clock gene expression differed between experimental photoperiod and SNP treatments. In experiment 2 significant seasonal differences were also observed in the amplitude of individual clock gene expression. The mechanisms underlying this and potential impact on seasonal physiology are unknown. Developmental changes such as the smoltification process or abiotic factors such as temperature or salinity should be further investigated. In mammals previous work has focused on the molecular switch for photoperiod response and regulation of thyroid hormone bioactivity via deiodinase mediated conversion of T4 to the biologically active form T3. In mammals and birds expression of key seasonal molecular markers i.e. Tsh, Eya3 and Dio2, are up-regulated hours after exposure to the first LD and III persist under chronic LD conditions. In order to confirm the involvement of these genes in the seasonal photoperiodic response in salmon, a microarray study was first carried out. Results displayed transcriptome level differences in the seasonal expression of a wide variety of target genes including Eya3 and Dio1-3 in relation to LD and SD photoperiod suggesting that these genes may have a conserved role in salmon. qPCR validations of selected genes of interest were then performed (Dio1, Dio2 and Dio3, Eya3 and Tshover diel cycles in fish exposed to LD and SD photoperiod (autumn acclimated fish). In addition an unrelated qPCR study was undertaken in salmon parr acclimated to LD, 12L12D and SD photoperiod (spring acclimated fish)(Dio2, Eya3 and Tsh. Consistent with findings obtained in other vertebrate species, circadian expression of Dio2 was observed under LD. However expression of Eya3 and Tsh appeared to be dependent on photoperiod history prior to acclimation to the experimental photoperiods as already suggested for clock gene expression in this thesis. This is potentially a consequence of direct regulation by clock genes. To our knowledge, this is the first report on the expression of key molecular components that drive vertebrate seasonal rhythms in a salmonid species. The thesis then focused on another key component of the photoneuroendocrine axis in fish, the pineal organ. In the Atlantic salmon, as in other teleosts the photoreceptive pineal organ is considered by many to be essential to the generation, synchronisation and maintenance of circadian and seasonal rhythms. This would be primarily achieved via the action of melatonin although direct evidence is still lacking in fish. In salmonids the production of pineal melatonin is regulated directly by light and levels are continually elevated under constant darkness. In non salmonid teleosts the rhythmic high at night/ low during day melatonin levels persists endogenously under constant conditions and is hypothesised to be governed by light and intra- pineal clocks. The aims of the present in vitro and in vivo trials were to determine if circadian clocks and Aanat2 expression, the rate limiting enzyme for melatonin IV production, are present in salmon, test the ability of the pineal to independently re-entrain itself to a different photoperiod and establish whether the candidate clock genes and Aanat2 expression can be sustained under un-entrained conditions. Expression of clock genes was first studied in vitro with pineal organs exposed to either 12L:12D photoperiod, reversed 12D:12L photoperiod and 24D. Clock gene expression was also determined in vivo, in fish exposed to 12L:12D. Results were then contrasted with an in vitro (12L:12D) investigation in the European seabass, a species displaying endogenous melatonin synthesis. Results revealed no rhythmic clock gene (Clock, per1 and per2) expression in isolated salmon pineals in culture under any of the culture conditions. In the seabass, Clock and Per1 did not also display circadian expression in vitro. However rhythmic expression of Cry2 and Per1 was observed in vivo in the salmon pineal. This suggested some degree of extra-pineal regulation of clocks in the Atlantic salmon. In terms of Aanat2 no rhythmic expression was observed in the Atlantic salmon under any experimental conditions while rhythmic expression of Aanat2 mRNA was observed in seabass pineals. This is consistent with the hypothesis that in salmonids AANAT2 is regulated directly at the protein level by light while in other teleosts, such as seabass, AANAT2 is also regulated by clocks at a transcriptional level.

Atlantic salmon (Salmo salar) parr-smolts were exposed to sublethal concentrations of cypermethrin, chlorothalonil, quintozene or atrazine to determine if they affected osmoregulation. After 96 h of exposure to a pesticide, Na+K+-ATPase, hematocrit, liver somatic index (LSI), plasma sodium, chloride, and cortisol concentrations were determined. There were no mortalities observed following a 24-h seawater challenge. No effects were seen with cypermethrin exposure. Chlorothalonil exposure resulted in increases in plasma Na+ concentrations following the seawater challenge in the 0.18 and 3.6 μg/L groups. For quintozene, decreases in LSI was seen at each concentration, and decreases in Na+K+-ATPase activity was seen at 0.55 μg/L as well as a decrease in Na+ concentrations at the highest exposure concentration. Atrazine exposure increased Na+K+-ATPase activity in the 1 and 100 μg/L groups, and plasma cortisol concentrations at100 μg/L. Overall, the pesticides examined had minimal effects on fish osmoregulation and stress at the concentrations tested.

Salmon aquaculture is the rearing of salmonids for commercial purposes. These practices are typically carried out in saltwater farms located in coastal waters. The process of siting these facilities requires identifying and selecting areas that are economically, socially and environmentally suitable to locate them. Siting salmon aquaculture facilities has become a controversial resource management issue in British Columbia (B.C.), where distance-based criteria ultimately determine the location of these facilities. This thesis focuses on providing insights and concepts to inform and examine the salmon aquaculture facility siting process in B.C. It is argued that regulatory processes and outcomes in the context of a new industry could respond to mechanisms and factors that shape governmental agendas, illustrating how policy can behave reactively rather than in a precautionary manner. In this case, the outcomes of such reactive policies are reflected in siting criteria that yield implicit environmental and socio-economic disadvantages and tradeoffs. This way, siting criteria derive from expert judgements based on best available information while their associated uncertainties may lead to consider less-desirable sites while underestimating or overestimating risks, and overlooking important regional objectives, cumulative impacts and stakeholder values. The thesis further suggests that the future evolution of the salmon aquaculture facility siting process in B.C. could benefit from siting processes that have already been developed and implemented by other sectors. Different lines of reasoning that deal with processes of public negotiation, analytical decision-making and a systems' approach are explored as ways by which the salmon aquaculture facility siting process could evolve in the future toward creating more comprehensive policy.

This thesis focuses on the classic problem of investment per offspring. It is an attempt to (i) reconcile theoretical research with empirical methods that can be used to test theory, (ii) test a fundamental prediction that arises from classic theory, and (iii) test one of the more recent theoretical developments. We use Atlantic salmon (Salmo salar) as a model organism. Drawing from the classic Smith–Fretwell model, we provide defensible definitions of offspring fitness that can be used in empirical studies, and we show using simulation that the Weibull-1 statistical model provides the best estimates of optimal investment patterns. Next, we apply these methods to mark-recapture data collected for juvenile Atlantic salmon. This experiment supports the prediction that parental reproductive success is maximized by increasing investment per offspring when environmental conditions become unfavourable. Having verified this prediction, we test a general extension of classic theory which broadly suggests that large-bodied females decrease the quality of the offspring environment, such that larger females in a population ought to invest relatively heavily in investment per offspring. This might occur, for example, when larger females have a greater fecundity and if optimal investment per offspring increases with sibling competition among non-dispersive offspring. The results of this experiment generally do not support the idea that large females decrease the quality of the offspring environment in Atlantic salmon. Finally, we also provide evidence against a verbal hypothesis that attempts to explain inter-population variation in egg size of salmonids as an adaptation to population-specific spawning substrates. We conclude that the classic model of egg-size optimization can be a useful tool for understanding patterns of reproductive allocation in nature, but that investment per offspring is an extremely complex trait that cannot be fully understood by invoking a simple optimality model. Variation in investment per offspring, especially that which occurs within populations, is most parsimoniously attributed to the physiological factors (e.g., variation in testosterone levels), morphological constraints (e.g., the size of the pelvic aperture) and genetic factors (e.g., genetic correlations arising from pleiotropic genes) that affect this phenotype and that constrain adaptive evolution of this trait.

Research for this study built on the experience of salmon restoration by exploring the lived experience of children ages eight to 12 who participated in an eight-month salmon restoration education program, the Salmonid Enhancement Program (SEP), through the Kamloops School District and the Department of Fisheries and Oceans (DFO). The study used a qualitative multimodal phenomenological approach that is theoretically framed through deep ecology and systems theory to answer: What meanings and impacts do children experience when participating in restoration projects? Data was gathered through: children's reflections from the experience, observations from the field experience, researcher reflections, photographs, children's drawings, and six follow-up semi-structured interviews collected from five participating classes in the Kamloops School District. The research will support the Kamloops School District and participating teachers better understand the meaning and experiences of youth participating in Salmonid Enhancement Program in order to create more inclusive program design in the future.

The role and functions of Urotensin II (UII), Urotensin II-related peptide (URP) and proangiotensin-12 (PA12) are currently ambiguous, either due their relatively new identification and isolation from their host species, or due to contrasting and conflicting reports observing the physiological and pathophysiological role of these spasmogens within the mammalian cardiovascular system. Accordingly, we sought to determine the true physiological functions of these peptides in both healthy and diseased states. The initial task was to reveal potential reasons for the contrasting responses to UII, and to define the role of UII within the isolated rat heart. UII and URP retain a highly conserved cyclic region, shown to be necessary in receptor binding and activation, with the high inter-species variance within the N-terminus reported to be of little importance. Our research revealed UII to be highly species-specific, stimulating potent, sustained vasodilation of the coronary arteries in response to the native form infused, while non-native UII peptides had either no effect, or caused significant vasoconstriction. UII-induced vasodilative effects were found to be mediated by nitric oxide and prostaglandin activity combined. Reviewing publications to date it was evident that many studies employed UII foreign to the host species, reporting potentially untrue effects, based on our findings. Recent studies have identified UII as a potent agent in developing and promoting atherosclerosis and coronary artery disease through UII-induced mitogenic activity and promoting foam cell formation. Hence, we observed the effect of infusing the native species of UII and URP into a model of cardiac ischemia-reperfusion. Both preconditioning the heart with UII or URP, or infusing UII or URP upon reperfusion caused significant coronary vasodilation following ischemia, and significantly attenuated ischemic-induced myocardial injury. These studies indicated elevating UII and URP provided a level of cardioprotection, not only when administered into healthy hearts prior to an ischemic event, but also in hearts having already undergone ischemia and the resultant endothelial damage. PA12 was the third peptide tested in the current thesis. Being newly identified and suggested to be a new component of the renin-angiotensin system (RAS) it was important to define the physiological role of PA12 upon the cardiovasculature, as the RAS is heavily associated with the development and progression of cardiovascular disease. Utilising the Langendorff isolated rat heart technique, PA12 was found to cause potent vasoconstriction of the coronary arteries, mediated by the angiotensin II type 1 receptor (AT₁R). Furthermore, using subjecting the perfusate samples to radioimmunoassay and RP-HPLC revealed PA12 was converted to AngII. Both PA12-induced vasoconstriction and generation of AngII were found to be dependent upon chymase activity, with inhibition of ACE1 having little effect. Myography was employed to further study the vascular response to PA12 throughout the rat arterial system from the common carotid to the femoral arteries. PA12-induced vasoconstriction displayed a potency gradient, with greatest constriction observed in vessels closest to the heart, with potency reduced and eventually lost further from the heart. PA12-induced vasoactivity was shown to be dependent upon both chymase and ACE1 activity, with ACE1 regulating PA12 activity with greater potency. The intracellular pathways stimulated in response to PA12 were defined using western blotting, with PA12 stimulating phosphorylation of ERK1/2, JNK, p38 and PKCα/β₁₁, but having no influence on PKCδ/θ. Stimulation of these pathways is consistent with the observed PA12-induced vasoconstriction, and also indicates that PA12 activation of AT₁R and the subsequent cytokines, could potentially stimulate hypertrophy, apoptosis, cell growth and differentiation, and inflammation, promoting cadiovascular remodelling and progressing atherosclerosis, hypertension and other vascular diseases if not sufficiently regulated. Taken together, these studies indicate PA12 may have a primary role within the local, tissue-based RAS, providing an alternate substrate to angiotensin I, while ACE1 is the primary regulatory enzyme within the circulation. Our findings also display the chymase-dependent PA12/AT₁R pathway as potential novel targets for pharmacological inhibition of RAS activity to ameliorate hypertension and maladaptive vascular remodelling.

Anadromous Pacific salmon (Oncorhynchus spp.) return annually from marine ecosystems to their natal freshwater habitat to spawn and die. Runs of spawning salmon provide an important source of nutrients and energy to watersheds. However, in coastal systems, substantial amounts of salmon-derived nutrients can be exported back to estuaries. Human land use, including agriculture and urban development, also contribute substantial nutrients to coastal ecosystems, and have the potential to confound results from salmon-derived nutrient studies. This thesis examines the influences of spawning salmon and human land use on stream nutrient and particulate dynamics, including export to estuaries. It also investigates the use of the stable isotope composition (δ13C and δ15N) of estuarine clams, the varnish clam (Nuttalia obscurata: Reeve, 1857) and the manila clam (Tapes philippinarum), and their food sources, as indices of the freshwater export of salmon-derived nutrients to estuaries. Samples were collected from three nearby river-estuary systems along Southeast Vancouver Island, British Columbia. Study systems had either a large number of returning salmon and little human land use (Goldstream), few returning salmon and extensive human land use (Shawnigan), or few returning salmon and little human land use (Holland). In Goldstream River, high abundance of salmon carcasses increased concentrations of total nitrogen and total phosphorus stream water below a barrier to upstream salmon migration. Carcasses also contributed substantial amounts of organic matter to the stream, as indicated by high δ13C and δ15N, and corresponding low C:N ratios in suspended particulate organic matter. My calculations indicate that between 51-77% of the phosphorus transported upstream by migrating salmon, was exported back to the estuary. Human land use also increased downstream nutrient concentrations and raised baseline δ15N in stream ecosystems, which is cause for concern and caution for salmon-derived nutrient studies in land use-affected watersheds, or in the reverse situation, for anthropogenic nutrient studies in watersheds that support runs of anadromous salmon. The high δ15N of anthropogenic nitrogen was not evident in the Shawnigan Estuary. In the Goldstream Estuary salmon-derived nutrients appeared to increase the δ15N of clams, and both the δ13C and δ15N of sedimentary organic matter (SOM), with more enrichment in the high intertidal zone near the river mouth, than in the mid-intertidal zone. The stable isotope composition of clams and SOM was relatively constant across the period of salmon spawning and carcass decay, indicating that they may reflect a legacy salmon-derived nutrient input into estuaries. This study demonstrates that substantial amounts of salmon-derived nutrients are exported back downstream to the Goldstream Estuary where they appear to become integrated into the estuarine food web. Data from a series of estuaries receiving a range of nutrients inputs from salmon is needed to confirm indices of salmon-derived nutrients in estuaries. There is also need for more extensive examination regarding the downstream effects of salmon-derived nutrients in areas such as estuarine productivity, community composition, and positive feedback mechanisms that influence salmon populations. This last area of research is of particular importance considering the high number of salmon stocks at risk in B.C.