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.

Heritabilties and genetic correlations using Individual Animal Model, (IAM), analysis for weight, length and survivability were determined in both freshwater and saltwater rearing of s0 and si1 coho, (Oncorhynchus kisutch). The most important trait to salmon farmers is the saltwater market weight which was found to have heritability estimates of 0.21 and 0.45 for the s1 and s0 smolts. Estimates of heritability for survival were high, (0.29 and 0.21) for both s0 and s1 rearing strategies. Genetic correlations between freshwater and saltwater size were small, (0.33 to 0.59) indicating selection for market weight should be done during the saltwater market weight window. Significant differences were found for weight and length between strains during freshwater and saltwater rearing for both s0 and si1 coho. The northern strains, (Kitimat, Bella Coola and Pallant Creek) were significantly larger in weight and length thanthe southern strains, (Big Qualicum and Robertson Creek). The Kitimat strain was larger in weight and length than the Bella Coola and Pallant Creek strains but lower than these two strains for percent survivability. When comparing fish from the Kitimat strain reared on both a s0 and s1 rearing strategy, it was found that the s1 fish were significantly larger than the s0 fish at the market weight window. / Land and Food Systems, Faculty of / Graduate

Sightings and acoustic recordings from 1984 to 1989 of northern resident killer whales (Orcinus orca) from Johnstone Strait off north eastern Vancouver Island and from King Island on the central British Columbia coast were analysed to examine the hypothesis that northern resident whales move seasonally in their range to areas where salmon are available. Killer whales were most abundant in Johnstone Strait between July and October and infrequent during the remainder of the year. The increase in whale abundance during summer coincided with the migration of salmon (Oncorhynchus spp.) from offshore into Johnstone Strait. The occurrence near King Island in spring 1989 of the same resident whales that are seen in Johnstone Strait during summer, coincided with runs of sockeye and chinook salmon. During July, August and September of 1984 through 1988, killer whale sightings were recorded virtually daily in the Johnstone Strait. Observations of killer whales in Johnstone Strait during the summer of 1988 showed that whales foraged along shore and in areas of strong current where salmon occur in high densities. Of the 16 killer whale pods in the northern resident community, however, less than half were present more than 15% of summer days (1984 to 1988). Regression results between numbers of whale days per week from each pod and numbers of salmon per week showed that the occurrence pods that were present on more than 15% of summer days in Johnstone Strait was positively and significantly associated with the abundance of sockeye and pink salmon (six pods). In addition to these, the occurrence of one pod that spent less than 15% of summer days in the Strait was positively and significantly associated with chum salmon. Together these results support the hypothesis that northern resident killer whales select their habitat seasonally to feed on available salmon. The results also lead to the hypothesis that within the northern resident community each pod has a seasonal home ranges. / Land and Food Systems, Faculty of / Graduate

An experiment was designed to determine whether the response of fish to graded dietary levels of essential fatty acids (n3) was affected by the total dietary lipid concentration. Juvenile coho salmon were fed practical diets varying in lipid source and total lipid content. The diets were fed in duplicate during a 27-week and a 12-week period ran in succession. The effects of the different dietary fatty acid concentrations on body fatty acids composition were determined after each period. The dietary fatty acid classes were expressed either as percent of the dry diet or percent of the dietary lipid. Analysis of the body lipid fatty acid composition was performed for neutral and polar lipid fractions. The effect of dietary fatty acid concentration on growth and mortality was determined over a 12-week growth study (period 2). A 24-hour saltwater challenge was performed at the end of period 2. It was used to examine the effect of dietary fatty acid concentration on saltwater tolerance. Dietary n6 and n3 fatty acids appeared to be selectively incorporated into the body polar lipid pool. Linoleate and linolenate underwent elongation and desaturation which resulted in the inhibition of the elongation and desaturation of 18:ln9. The neutral lipid pool served as a source of n3 fatty acids for the polar lipid when dietary intake was limited by low temperatures during period 1. The body neutral monounsaturated and 18:1 monounsaturated fatty acids consistently reflected the composition of the diet. The n3 fatty acid concentration in the neutral lipid was also directly related to the dietary fatty acid composition during period 2. The effect of dietary fatty acids on the body neutral or polar fatty acid composition did not depend on the manner in which the dietary fatty acids were expressed. There was also no significant effect of dietary total lipid concentration on the relationship between dietary fatty acids and their incorporation into the body lipids. The growth response was difficult to interpret because of the high mortality. There was a significant difference in mortality among treatments. A positive relationship between dietary concentrations of total n3 fatty acids or n3 highly unsaturated fatty acids and mortality became evident following analysis of the regression of mortality as a function of dietary fatty acid composition. The dietary fatty acid composition did not appear to alter the saltwater tolerance of the 1+ coho salmon. / Land and Food Systems, Faculty of / Graduate

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. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate

Coho salmon (Oncorhynchus kisutch) from six hatcheries operated by the Canadian Department of Fisheries and Oceans Salmonid Enhancement Project, were reared in a common facility and then subjected to a series of standardized challenge tests. Results suggest that there are genetically based differences in the response to stressful challenges among stocks of coho salmon from southern British Columbia. The challenge tests were: saltwater (30ppt); saltwater and an increase in temperature (30ppt and 4°C); high pH (9.4 and 10.0); low pH (3.55, 3.65, 3.75 and 4.1); thermal tolerance (1°C/h); and handling (30s netting). The measured parameters were plasma sodium and chloride ion concentrations for the saline and pH challenges, time to dysfunction in the thermal tolerance challenge and plasma glucose concentration in the handling challenge. No differences among stocks were found in responses to the high pH and thermal tolerance challenges. The Chehalis River stock had the smallest plasma ion increase in salt water but showed the largest plasma ion decrease in acidic waters. In some of the low pH challenges the Tenderfoot Creek stock showed less plasma ion loss than other stocks. The stock from Eagle River had the lowest plasma glucose concentration increase during handling challenges. The combined saltwater and temperature increase challenge demonstrated the cumulative effect that stressors can have. Sampling associated with the handling challenges revealed a diurnal fluctuation in resting plasma glucose concentrations. The low pH and handling challenges showed that stock performance and the magnitude of the response observed varied with rearing conditions. Although there was some variation in the magnitude of the stock response to challenges between the two rearing conditions used, differences among stocks were consistent. When the response to all challenges were assembled into a relative challenge response profile (or performance profile), each stock was unique. / Land and Food Systems, Faculty of / Graduate

Digestible carbohydrate is commonly encountered by chinook salmon {Oncorhynchus tshawytscha) in practical culture diets, although little is known regarding its utilization. This study was undertaken to examine (1) the effects of a high carbohydrate diet and (2) glucose tolerance in chinook salmon of selected British Columbia strains. Yearling chinook salmon of three strains were fed to satiation either a high or a low carbohydrate diet for 63 days. The diets were isonitrogenous, and contained respectively 30 % gelatinized wheat starch or an equicaloric amount of herring oil. There was an overall reduction in growth of chinook fed the high-carbohydrate diet over the 63-day feeding period. Although specific growth rates declined initially in the high carbohydrate-fed groups, they were comparable to those of control groups in the final third of the trial, indicating an adaptation response. Chinook fed the high carbohydrate diet had increased carcass protein and ash, and decreased carcass fat levels relative to controls. Feed intake was generally lower in these groups, and differences in feeding response were observed between diets and strains. Although feed and energy efficiencies were reduced in chinook fed the high carbohydrate diet, protein utilization was comparable on the two diets, indicating a protein-sparing effect of the carbohydrate. Consumption of the high carbohydrate diet led to significant elevations in hepatosomatic indices (HSI) and liver glycogen (LG) concentrations. In Quesnel chinook, LG levels exceeding 10 % did not appear to have any detrimental effects on feeding, growth or health. LG concentrations and HSI fell to basal levels in all groups 21 days after feed withdrawal. Some strain differences were evident. For example, Big Qualicum chinook fed the high carbohydrate diet exhibited the lowest liver glycogen accumulation, highest rate of carcass fat deposition, and best energy efficiency ratios relative to control groups, suggesting a difference in carbohydrate metabolism in this strain. On the other hand, Quesnel chinook exhibited the highest relative growth on the high carbohydrate diet. Mortality, although unaffected by diet in the Quesnel and Robertson Creek chinook, appeared to be higher in high carbohydrate-fed Big Qualicum chinook. In the second part of the study, chinook salmon subjected to an oral glucose tolerance test displayed pronounced and persistent hyperglycaemia, indicative of poor glucose tolerance. Strain differences were evident in the magnitude of response. Acclimation to a high carbohydrate diet prior to testing resulted in a significantly reduced elevation of blood glucose, indicating an adaptation response. While plasma glucose concentrations approached 500 mg/dl in some trials, plasma insulin concentrations exhibited a two-fold rise, with indistinct peaks. Plasma glucose and plasma insulin concentrations were poorly correlated, indicating that glucose is a poor insulin secretagogue in chinook salmon. / Land and Food Systems, Faculty of / Graduate

An investigation was initiated in southern British Columbia during 1984 to determine the degree of similarity between populations of coho salmon, in terms of their demographic traits and exploitation patterns. Fourteen stocks of wild or hatchery origin were subject to coded-wire tagging in nine different streams located within a 150 km region of southeast Vancouver Island during 1985,1986, and 1987. Escapement enumeration and tag recovery were conducted during the 1985-1988 period in all streams by means of counting fences and stream surveys. A new mark-recapture model was formulated specifically for estimating escapement levels in natural streams where only a partial enumeration of spawners is possible. Estimates of the number of tags recovered in various sport and commercial fisheries were generated primarily on the basis of catch and sampling records extracted from the Mark-Recovery Program database, located at the Pacific Biological Station of the Canadian Department of Fisheries and Oceans. Estimates of sampling rates in the Strait of Georgia sport fishery were determined from simulation studies based on catch and sampling statistics associated with the Georgia Strait Creel Survey and Head Recovery programs. Populations were contrasted in terms of their juvenile migration patterns, smolt-to-adult survival, catch distributions, straying rates, escapement patterns, run composition, adult sizes, and exploitation rates. Considerable variation in smolt size and juvenile migration time was detected among populations each year. The most pronounced difference was the consistently shorter migration period of smolts released from public hatcheries. Estimates of ocean survival was highly variable across years and streams, and even among stocks within the same stream. No particular stock or stock type had consistently higher survival, but hatchery fish from the Big Qualicum River exhibited consistently lower survival. Considerable variation was observed in the duration and timing of various runs within the study area. On average, the contribution of strays to each spawning population was relatively small (< 2%), but strays could account for as much as 50% of the escapement to a given stream. Average exploitation rates were in the neighborhood of 80% each year, but were as high as 96% for some stocks. Substantial differences in exploitation rate were detected between stocks from the same stream, and between stocks from adjacent streams, but exploitation rates were not consistently higher or lower for any particular stock or stock type. The influence of specific factors upon straying rates, survival rates and exploitation patterns was estimated by means of log-linear models. Stock contributions to various fisheries appeared to be related to the release location, and two stock assemblages were identified within the study area based on the level of similarity among stocks in fishery contribution. Attempts to quantify the level of co-variation among stocks in survival and exploitation rates were hampered by the lack of sufficiently long time series of data, but preliminary results gave no indication of a high level of similarity among stocks or stock types. Still, it was possible to identify stocks which could be used as indicators of the general status of all stocks in the study area in terms of escapement trends, smolt-to-adult survival and exploitation rates. Based on the level of similarity observed, indicator stocks are considered to be useful stock-assessment tools, and can provide useful information for management purposes. / Science, Faculty of / Zoology, Department of / Graduate