Lamont, Carole Ann

Rainbow trout {Oncorhynchus mykiss) and coho salmon (0. kisutch) produce males which mature at an abnormally early age. The objectives of this study were to critically describe the role of growth rate in early sexual maturation of male salmonids by monitoring growth rate and precocious sexual development in individually identified fish. Underyearling rainbow trout were individually identified using coded tags. These fish were reared at 9°C and 15°C and growth was monitored twice a month in both...

Ashton, Heather

In Experiment 1, eggs of Big Qualicum (BQ) and Robertson Creek (RC) wild and cultured Chinook salmon (Oncorhynchus tschawytcha) were analyzed for lipid composition and fatty acid profiles. Each of the cultured broodstocks had been fed two formulated diets designated as COMM and WV33. Significantly higher concentrations of saturated and n3 fatty acids and lower concentrations of n6 and n9 fatty acids were found in both the total and polar lipids of the eggs from the wild fish than in those from ...

Levy, David Alan

The widespread occurrence of diel vertical migration behavior in pelagic aquatic organisms suggests that there is a selective advantage of the behavior compared to a static vertical depth distribution in the water column. Juvenile sockeye salmon (Oncorhynchus nerka) are active diel vertical migrators within pelagic lacustrine habitats, usually migrating over vertical distances covering tens of meters. The migrations are timed such that the animals occupy shallow depths during crepuscular and noc...

Courtenay, Simon Charles

This study addressed the hypothesis that coho salmon (Oncorhynchus kisutch) learn and remember the odours of their natal environment. During one or more of the embryo, alevin and early fry (first 14 d) stages, fish were exposed to the artificial odorant morpholine, natural odorants generated by conspecifics, or creek water. After an interval of at least 1 month the preference of fry for an odorant was tested in a Y-maze and compared to that of naive fry. Increased preference was interpreted as r...

Taylor, Barbara Elan

To realise the potential for mussel culture in British Columbia, mariculture research must identify specific environments and suitable locations which promote maximum growth in mussels. The present study investigates the possible advantages, through nutritional enrichment, of salmon farms as sites for mussel culture. Mussels were cultured at different distances around two salmon farms on the east coast of Vancouver Island (Departure Bay and Genoa Bay). Three parameters of mussel growth: conditi...

Bernatsky, Ivor Paul

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 die...

Foote, Christopher J.

The genetic relationship of anadromous (sockeye salmon) and non-anadromous (kokanee) Oncorhynchus nerka was examined in conjunction with the breeding behaviour of the two forms to determine: (1) if there is evidence of genetic divergence between the forms where they spawn sympatrically; (2) if such divergence is associated with significant premating isolation between the forms and; (3) if premating isolation results directly from the size difference between the forms (sockeye are much larger tha...

Tolson, Graeme M.

The locomotor responses of juvenile and adult sockeye salmon (Oncorhynchus nerka) to concurrent changes in temperature and salinity were examined in a controlled laboratory setting. I hoped to better understand how these environmental factors influence the coastal movements of migrating salmon. Juvenile sockeye were captured during the downstream migration from Great Central Lake on Vancouver Island, British Columbia, Canada. The fish were acclimated for 1 wk at 10°C, 20 ppt, and then tested in...

O'Neill, Sandra M.

Evidence supporting the hypothesis that competitive interactions occur between juvenile sockeye salmon and limnetic sticklebacks in an oligotrophic lake was obtained by manipulating fish abundance, size and species combinations in limnetic zone enclosures in Kennedy Lake, British Columbia. Sockeye and sticklebacks were stocked at densities within the range known to commonly occur in British Columbia coastal lakes. In all fish-treatment enclosures, fish grazing pressure quickly reduced the abunda...

D'Amours, Denis

Within the environmental approach for the study of fluctuations in fish population abundance, factors that may regulate the overlap in time and space (phasing) of fishes, food supply, and predators, are sought. This trophic phasing analysis is based on the recognition that production of food is a process at least partially independent of the production of consumers. Trophic phasing analysis was applied in investigating production of chum salmon in the Fraser River estuary. Juvenile chum salmon w...

Forster, Ian

Highly unsaturated marine lipids are common ingredients in salmon diets, and they are prone to oxidative change. The present study was undertaken to examine the growth and health of coho salmon (Oncorhynchus kisutch) fed diets containing herring oil autoxidized to different degrees. The efficacy of dietary vitamin E in ameliorating any adverse effect on performance was investigated. Herring oil was oxidized to one of two levels (relative to a control) by aeration and mild heating (40 °C). Perox...

Borland, Marjory

Size-assortative mating was studied in freshwater Gasterosteus aculeatus from two sites on the Salmon River, British Columbia. In the upper river females tend to be larger than males but in the lower river females are generally smaller than males. Male size is similar in both areas. The hypothesis tested was that female size influences male mate choice. Freshwater males from the two areas showed a pronounced difference in mate preference with respect to female size. In choice tests, males from ...

Wood, Christopher Charles

Common mergansers (Mergus merganser) can inflict serious mortality on salmonid populations when abundant on salmon and trout-rearing waters. I examined the foraging behaviour and dispersion of mergansers to determine when, and where, aggregations of these ducks are likely to occur on salmonid streams on eastern Vancouver Island, B.C. First, I investigated the effect of fish availability on a merganser's hunting performance and its choice of feeding site by stocking enclosed sections of a natural...

Rosenau, Marvin Leslie

Interpopulation variability in electrophoretically detectable isozyme frequencies, morphology, meristics and migratory behaviour has been demonstrated in many studies for salmonids and these character differences are known to often have an inherited basis. In this study, agonistic behaviours were compared in two British Columbia lower mainland populations of juvenile coho salmon and inherited differences were shown to occur. Using mirror image stimulation techniques, recently emerged laboratory...

Moussalli, Elie Ibrahim

A simple life history model that analyzes the relationships between habitat capacity, survival rates, optimal escapement, and harvest rate for Pacific salmon (Oncorhynchus spp.), is implicit in nearly all considerations of salmon management. This model consists of density dependent events at spawning and rearing, and density independent prespawning mortality, egg-to-fry survival and smolt-to-adult survival. The analysis of this model yields simple relationships between key parameters and optimal...

Millington, Peter

Fishermen are predators whose functional and numerical responses to prey can be studied. I review the fishery literature and discuss how much of it can be viewed in the context of a predator-prey system. I examined the numerical response, aggregation and movement of boats in response to fish abundance, in the British Columbia salmon gillnet fleet using catch data by area for the period 1979 to 1981. In any one year, for the whole coast, there was a strong relationship between the return (catch ...

Berg, Linda

The territorial and feeding behaviour of juvenile coho salmon was studied in an artificial stream channel in response to short-term pulses of suspended sediment. Disruption of the social organization of the fish resulted at the higher turbidities tested. Dominance hierarchies were partially broken down, and territories were no longer defended. Only at lower turbidities were the hierarchies reformed and territories re-established. Behaviour following water clearance, closely resembled that observ...

Mace, Pamela M.

Mathematical models describing the components of predator-prey interactions are reviewed and evaluated, and new equations representing selected aspects of the relationship are proposed. A model of prey selection that distinguishes between predator performance and prey vulnerability is devised and shown to lead to conclusions that may be qualitatively different from those produced using previous methods. The feeding habits of staghorn sculpins (Leptocottus armatus), the extent to which they util...

Woodsworth, Eric John

The predatory functional response is one of the important components of the interaction between predator and prey populations. This response has not been measured for fish predators and fish prey, in spite of the demonstrated importance of predation in regulating numbers in populations such as the juvenile salmon system used in this thesis. Laboratory exeriments were conducted to determine the form of the functional response of the prickly sculpin (Cottus asper), a common freshwater predator, to...

English, Karl K.

A feeding experiment was designed to examine how fish growth rates are affected by the size abundance of pelagic zooplankton. Juvenile chinook salmon, Oncorhynchus tshawytscha , were raised in 90 m³ mesh enclosures in Saanich Inlet, B.C. The enclosures permitted ample water and zooplankton circulation while retaining 5-6 gram juvenile salmon. The enclosed fish grew at an average rate of 1.8% wet body weight/day for a six week experimental period. Weekly growth rates ranged from 3.9%/day while fo...

Pawaputanon, Kamonporn

Sockeye salmon parasitized with Salmincola californiensis were compared experimentally with unparasitized fish of the same age to determine: (1) its effects on growth; (2) effects on parasitized fish under some environmental stresses and (3) hematological effects of this parasite on its fish host. It was found that average infection levels of 31.25 parasites per fish can reduce the weight of the fish host by almost 34 % within a period of 112 DPI. The rate of increase in length of the infected...

Murray, Clyde Bruce

This study provides comparative data on the effects of temperature on zygote and alevin survival, rate of development to 50 percent hatching and emergence, and alevin and fry size for five species of Pacific salmon (Oncorhynchus) and for rainbow trout (Salmo gairdneri). Fertilized eggs from each species were incubated in controlled temperature baths at five constant temperatures (2°, 5°, 8°, 11° and 14°C). At 2°C, survival for coho salmon zygotes was high (85 percent), moderate for sockeye salmo...

Kruzynski, George M.

Laboratory experiments were conducted to study the effects of dehydro-abietic acid (DHA) on the physiology of the adaptation of sockeye salmon smolts (Oncorhynchus nerka) to sea water. Dehydroabietic acid occurs in the rosin of commercially important coniferous trees and is found in the untreated effluents of the pulp and paper industry at concentrations acutely toxic to salmonids. As this resin acid is known to be one of the more persistent toxic components of kraft mill effluent (KME) and alt...

Nomura, Daniel Kenichi

The purpose of this study was to determine whether or not weak electrical fields affect salmon troll success in target species Oncorhynchus tschawitscha Walbaum and Oncorhynchus nerka Walbaum. The study was conducted aboard a commercial salmon troller in two fishing areas of the Strait of Georgia, British Columbia. The two fishing areas were Canadian fishing statistical areas 29A and 17. There were two experimental fishing periods, 20 March to 22 May, 1978 and 2 September to 24 September, 1978 d...

Delaney, Peter Wayne

Various aspects of downstream migratory behavior of sockeye salmon fry (pncorhynchus nerka) were examined in a series of field and laboratory experiments. The field work at the Department of tie Environment (Fisheries and Marine Service) Fulton Eiver spawning channels, Babine Lake, British Columbia, was concerned with the predation by rainbow trout (Salmo gairdneri) and whitefish (Prosopium williamsoni) on sockeye fry with various kinds of prior experience. The laboratory studies focused on the ...

Jampolsky, Abey

An alkaline extract from the anterior lobe of the beef pituitary proved a potent source of a growth hormone with injections to rats. Injections of this extract to goldfish resulted in an 18% weight increase within eight days, which appears significant when compared to their controls. A similar method of preparation was used for an extract of the pituitary gland of the Pacific Salmon, Onoorhynohus tschawytscha. Injections of this extract failed to accelerate the growth of test rats. Injections to...

Foskett, Dudley Robert

Tie conditions in a geologically youthful area are outlined, and also the chemical and biological conditions in Bear Lake of the Skeena watershed. The life history of the sockeye, Qncorhynchus nerka, in this area is outlined as closely as information permits. The spawning of the sockeye where stream conditions are generally unfavourable and the probability of lake spawning in the deeper waters is discussed. The contribution of this area in relation to the whole Skeen sockeye run is estimated. / ...

Stringer, George Everett

Coho underyearlings settle toward the bottom when illumination decreases. The critical intensity for this response was found to be approximately 1 foot candle. A study of the nipping phenomenon in coho and kamloops trout revealed that coho nip more Intensively than trout in a homotypic group. However; in a heterotypic group of equal numbers, trout nip more readily. In a heterotypic group coho nip less frequently and show a preference to nip other coho. By comparison, the nipping Intensity of tr...

Parker, Robert Ray

Life history events of chinook salmon preclude determination of a critical size for this species by established methods. The use of size, rather than age, as a basic correlate of growth rate is discussed and compared to analagous treatment of physiological rates described in literature. Ecological opportunity and physiological opportunity are visualized as the two interacting components that determine growth, both of which are related to size attained. Growth opportunity occurs in stanzas which ...

Dales, Samuel

Chum salmon eggs were immersed in thyroxine, in thiourea, in halide salts, and in adrenalin on the day of fertilization and were maintained in these solutions until several months after hatching. All treatments affected growth either favourably or adversely, but only thyroxine and chloride changed body proportions. The changes due to chloride were significantly smaller than those following thyroxine treatment, and it is postulated that they are not “thyroxine-like” in nature. Thiourea inhibited ...

McInerney, John Edward

The seasonal salinity preference of four species of Pacific salmon was examined. Each species showed a strong preference for hypertonic seawater during the normal period of migration. Pink fry (Oncorhynchus gorbuscha) and coho yearlings (O. kisutch) lost this preference during the summer in contrast to Chum fry (O. keta) and sockeye yearlings (O. nerka). Three other types of behaviour showed seasonal changes consistent with a transitory "migration disposition". A preference for hypertonic seawa...

Platzer, Edward George

The life cycle of Phflonema oncorhynchi was studied in sockeye salmon, Oncorhynchus nerka, from Cultus Lake, British Columbia. Gravid female worms from the coelom of sockeye spawners burst in lake water releasing living first-stage larvae. These were ingested by Cyclops bicuspidatus and developed to the infective third stage in the haemocoele. Development required 17 days at 12 C or 70 days at 8 C. Each of six hatchery-reared sockeye fingerlings were fed 14-70 copepods infected with third-stage ...

Shelbourn, John Edward

Underyearling chum fry were held in fresh water and salt water at two different temperatures and under two different photoperiods. The first tests were made after forty days acclimation. Aggregations were greater in salt- than in freshwater (p < 0.01). At the lower temperature the fish were more aggregated than they were at the higher temperature (p < 0.05). Photoperiod effects were not significantly different. The biological meaning of these results is discussed. It is concluded that, under the...

Pletcher, Ferdinand Tony

The analysis of the life history was carried out from collections that were predominantly Lampetra planeri from the Salmon River and Entosphenus tridentatus from the Nicola and Thompson Rivers and from Vancouver Island streams. The taxonomy of British Columbian lampreys is reviewed and characteristics determined for separating large ammocoetes. The duration of adult life, distribution within streams, length, sex ratio, and fecundity was determined for both species. The spawning behaviour of bot...

Hafeez, Mohammad Abdul

The pineal organ in sockeye salmon and its relation with other epithalamic components has been studied. Histological and histochemlcal methods were used and the influence of experimental photoperiods on the histology and secretion in the juvenile pineals investigated. Photosensory and supporting ependymal cells have been identified. Lipofuchsin and melanin are absent in the pineal epithelium. Besides sensory fibres, efferent end-loops are present on the sensory and supporting cells. The dorsal p...

Fraser, Frederick James

The fry of the very similar salmonids, coho salmon (Oncorhynchus kisutch) and steelhead trout (Salmo gairdnerii), live in very close association with each other during their first year of life in fresh water. The present study was designed to measure the effects of competition between these species. Populations of different densities of coho and steelhead fry in four identical artificial stream-channels were studied. Observations were made on survival, growth rates, and some aspects of behavior....

Byrne, John Edward

Supervisor: N. R. Liley The endogenous and exogenous factors contributing to a diel rhythm of locomotor activity in juvenile sockeye salmon Oncorhynchus nerka (Walbaum) were examined in the laboratory. The basic measure employed in the investigation was spontaneous locomotor activity. High frequency sound (800 kHz) was used as a monitoring technique to collect continuous activity records. Three major areas received attention. First, a description and analysis were provided for the entrained di...

Wilson, Nadine

The neurohypophysial hormones of Pacific chinook salmon (Oncorhynchus tschawytscha) were purified and the amino acid sequence of both hormones determined. The extraction and purification procedure was developed in an effort to maximize the yields of pure hormones. Pituitary glands were extracted at 4°C using 0.2 M acetic acid. Purification consisted of gel filtration, ultrafiltration, and ion exchange. Gel filtration on Sephadex G-15 columns was used to separate neurohypophysial peptides from ...

Todd, Ian St. Pierre

Exploitation of Skeena River sockeye salmon (Oncorhynchus nerka) has been conducted almost solely by drift gillnets since inception of the commercial fishery in 1877. Selective action of gillnets is a factor which may have contributed to a long term decline in sockeye production and to other features of the population biology. This study was designed to determine the selective properties of nylon gillnets presently in use; to compare these with properties of linen nets used prior to 1955; to adj...

McLeay, Donald J.

The activity of the pituitary-interrenal axis in juvenile coho salmon (Oncorhynchus kisutch) and the relationship of this activity to the numbers of circulating leucocytes has been studied, using histological and histometric techniques. To this end, the effects of injections of mammalian ACTH, of Cortisol acetate and of dexamethasone on the interrenal tissue, on the epsilon cells in the pituitary gland, and on the differential leucocyte counts were investigated. In addition, the activity of the ...

Urquhart, Ian Thomas

This study explores the politics of regulating the British Columbia and Washington commercial salmon fisheries between 1937 and 1984. The principal focus of this comparative-historical study is upon one particularly striking exception to the tendency of regulators to tighten commercial salmon fishing restrictions over time - the persistence of liberal offshore trolling regulations. The dissertation argues that the anomalous treatment of the offshore troll fishery during this period may be ascrib...

Groot, Erick P.

Intertidal spawning of chum salmon, Oncorhynchus keta. was investigated by measuring egg survival, development, and saltwater tolerance under actual and simulated intertidal conditions. Intragravel salinity and temperature were monitored in the intertidal zone of Carnation Creek, British Columbia, using salinity and temperature probes implanted in the gravel at five locations, ranging from the 1.9- to 2.9-meter tide level. Artificially implanted eggs, placed adjacent to these probes, were monito...

Radcliffe, Roland Wootton

Goldfish (Carassius auratus L.) and cohoe salmon fry (Oncorhynchus kisutch Walbaum) were acclimatized to 20°C. and 3°C. respectively. The fish were placed one at a time once a day for ten days in a rotating annular chamber and the cruising speed was found. Then various fin combinations were clipped off and the fish were given ten more trials. The mean cruising speeds before and after clipping were compared. The clipped fish suffered no loss in ability to swim at a constant rate. Cruising-speed ...

McDonald, John George

The seasonal and diurnal movements of sockeye, pink and coho salmon fry are described. For sockeye, at least, the time of the seasonal migration froa the spawning area is related to the temperature "budget" during their period of development in the gravel. Their seasonal migration occurs earlier following an incubatory period in which above average temperature prevailed and later following relatively low temperatures. Emergence from the gravel appears to occur normally only after a certain...

Chowdhury, Niranjan Krishna

The activity of the tryptic enzymes occurring in the pyloric caeca of several salmons has been measured with respect to the effects of pH, ammonium chloride concentration and temperature on the enzyme bate material prepared from it. Several defferent methods of preparing a commercial bate have been investigated. From these data, an economic estimate of the feasibility of the production of leather bates from salmon pyloric caeca has been made. A sample of bate has been submitted for commercial te...

Chong, Shiow Ying

Parasitic isolates of Saprolegnia diclina Humphrey from Coho salmon (Oncorhynchus kitsutch Walbaum) were grown under controlled laboratory conditions to test the effect of environmental parameters on growth. This study points out the significance of medium selection and methods of determining growth in introducing variability into the results of experimental studies of parasitic Saprolegniaceae. The results indicate that there is a significant effect of temperature and pH on growth and morpholog...

Levy, David Alan

The feeding behaviour of juvenile chum salmon, Oncorhynchus keta, was analysed using a combination laboratory and field technique. The effects of experience with a single prey type were simulated by feeding animals in the laboratory with one of the following food types - the amphipod Anisogammarus confervicolus, the mysid Heomysis mercedis, or Oregon Moist Fish Pellets. After 30 days of laboratory experience, the experimental animals were marked and released into an intertidal creek of the Squam...

Iwama, George Katsushi

The interrelationship of bacterial kidney disease, a chronic disease of cultured salmonids, and an environmental toxicant, sodium pentachlorophenate, in juvenile chinook salmon, over time, was studied. This was carried out by monitoring various haematological parameters in the fish exposed to the two factors, singularly and in combination. An evaluation of these parameters as useful indices of stressful states imposed by the treatment was also attempted. Furthermore, external and internal physic...

Funk, James D.

This study was undertaken to determine whether the gonads of pink salmon (Oncorhynchus gorbuscha), could be stimulated with exogenous hormones to reproductive maturity one year earlier than normal. This procedure, if successful, could be used as a method for repopulating ‘off’ year cycles of pink salmon in numerous rivers in British Columbia and Washington. In the juvenile males, complete sexual maturity was attained by September in the year of hatching with thrice-weekly treatments of 10.0 mi...

Mänttäri, S. (Satu)

Abstract The dihydropyridine receptor (DHPR) in the skeletal muscle plasma membrane functions as a voltage sensor for excitation-contraction coupling. In the present work the expression and special features of DHPR were studied under various conditions. In order to localize and visualize the DHPRs, a method using fluorophore-conjugated dihydropyridine molecules as a probe was developed. In addition, different laboratory assays and electrophysiological measurements were used to study the express...