| detection of infection and susceptibility of different pacific salmon stocks (oncorhynchus spp.) to the haemoflagellate cryptobia salmositica. | the haematocrit centrifugation technique, modified by keeping the haematocrit tubes cold (between 1 and 10 c), was sensitive for detecting light infections of cryptobia salmositica (as few as 75 flagellates per ml of blood). in wet mount preparations, infections lighter than 7.5 x 10(3) flagellates per ml of blood could not be detected consistently. different pacific salmon stocks from british columbia demonstrated differences in susceptibility to c. salmositica in experimental studies using lab ... | 1984 | 6470889 |
| plasma levels on thyroid hormones in sockeye salmon (oncorhynchus nerka) decrease before spawning. | blood samples were taken from mature sockeye salmon (oncorhynchus nerka) at various stages in their upstream migration to spawn at adam's river in british columbia, canada. plasma t3 and t4 levels decreased significantly in both males and females between time of entry into fresh water and postspawning. | 1983 | 6667848 |
| postglacial genetic differentiation of reproductive ecotypes of kokanee oncorhynchus nerka in okanagan lake, british columbia. | okanagan lake, south-central interior of bc, contains two reproductive ecotypes of kokanee oncorhynchus nerka; individuals spawn in tributary streams ('stream-spawners') as well as on shoreline gravel areas ('beach-spawners'). we tested the hypothesis that these sympatric ecotypes comprise a single panmictic population by assaying variation in morphological traits and at allozyme, mitochondrial and minisatellite dna loci in fish collected from three stream-spawning and two beach-spawning sites. ... | 1997 | 9200826 |
| parvicapsula minibicornis n. sp. (myxozoa, myxosporea) from the kidney of sockeye salmon (oncorhynchus nerka) from british columbia, canada. | a new species of myxosporea parvicapsula minibicornis is described from the kidney of adult sockeye salmon (oncorhynchus nerka) that had recently returned from the pacific ocean to weaver creek, a tributary of the fraser river, british columbia, canada. spores are ovoid, symmetrical, with 2 pyriform polar capsules at the anterior pole. the posterior pole has 2 small, pointed projections. mean spore dimensions are length 11.0 microm, thickness (perpendicular to suture plane) 6.8 microm, and width ... | 1997 | 9406793 |
| renal infestation with parvicapsula minibicornis in wild sockeye salmon from the harrison and adams rivers in british columbia. | | 2000 | 10769771 |
| distribution, prevalence and severity of parvicapsula minibicornis infections among anadromous salmonids in the fraser river, british columbia, canada. | polymerase chain reaction (pcr) and microscopic examination of stained kidney sections were used to diagnose infections with the myxozoan parasite parvicapsula minibicornis in maturing fraser river salmon. in 2 series of collections, the parasite was detected in 109 of 406 migrating sockeye salmon oncorhynchus nerka belonging to early stuart, early summer and summer run-timing groups, mainly upper fraser river stocks. however, the parasite was detected neither in fish at sea nor once they had mi ... | 2003 | 12718470 |
| magnification and toxicity of pcbs, pcdds, and pcdfs in upriver-migrating pacific salmon. | the depletion of lipids associated with pre-spawning migration of pacific salmon has the potential to magnify concentrations of hydrophobic organic contaminants (hocs), which elevates risk of toxic effects. we present data from a field study of sockeye salmon (oncorhynchus nerka) migrating to spawn in great central lake, bc, which demonstrate that pre-spawning migration causes a magnification of pcb, pcdd, and pcdf concentrations in female gonads (1.9-2.5-fold), female soma (3.4-5.6-fold), and m ... | 2004 | 15597874 |
| assignment of sockeye salmon (oncorhynchus nerka) to spawning sites using dna markers. | randomly amplified polymorphic dna (rapd) markers were used to assign individual adult sockeye salmon to their spawning sites using a genotype assignment test. six primers were selected for use by screening bulked dna samples for markers missing in fish from one or more of 5 sites in british columbia or alaska. of 73 markers scored, 54 showed variation between or within sites among the sampled fish. thirty-seven of the variable markers were not detected in any fish from one or more sites; 18 var ... | 2005 | 15976939 |
| concentrations and fluxes of salmon-derived polychlorinated biphenyls (pcbs) in lake sediments. | fourteen sediment cores were collected from 10 lakes spanning a large gradient of sockeye salmon returns (0-40 000 spawners km(-2)) in alaska and british columbia in 1995-98 and 2002/03. the cores were analyzed for 210pb to determine sedimentation rates and focusing factors. polychlorinated biphenyl (pcbs) concentrations in the surface sediments (0-2 cm) were highly correlated with the number of sockeye salmon returns to each nursery lake. for 2002/03, the correlation between pcb concentration a ... | 2005 | 16201625 |
| mechanistic basis of individual mortality in pacific salmon during spawning migrations. | reproductive-based migration is a challenging period for many animals, but particularly for pacific salmonids, which must navigate from the high seas to freshwater natal streams. for the first time, we attempt to answer the question as to why some migratory adult pacific salmon die en route to spawning grounds. summer-run sockeye salmon (oncorhynchus nerka) were used as a model, and the migration behavior of 301 fish was followed by intercepting them in the ocean about 215 km from the mouth of t ... | 2006 | 16869433 |
| lipid reserve dynamics and magnification of persistent organic pollutants in spawning sockeye salmon (oncorhynchus nerka) from the fraser river, british columbia. | pacific sockeye salmon (oncorhynchus nerka) can travel several hundred kilometers to reach native spawning grounds and fulfill semelparous reproduction. the dramatic changes in lipid reserves during upstream migration can greatly affect internal toxicokinetics of persistent organic pollutants (pops) such as pcbs, pcdds, and pcdfs. we measured lipid content changes and contaminant concentrations in tissues (liver, muscle, roe/gonads) and biomarker responses (ethoxyresorufin o-deethylase or erod a ... | 2007 | 17539508 |
| bayesian decision analysis for evaluating management options to promote recovery of a depleted salmon population. | the endangered population of sockeye salmon (oncorhynchus nerka) in cultus lake, british columbia, canada, migrates through commercial fishing areas along with other, much more abundant sockeye salmon populations, but it is not feasible to selectively harvest only the latter, abundant populations. this situation creates controversial trade-offs between recovery actions and economic revenue. we conducted a bayesian decision analysis to evaluate options for recovery of cultus lake sockeye salmon. ... | 2008 | 18241234 |
| first record of human infection with the tapeworm diphyllobothrium nihonkaiense in north america. | the tapeworm diphyllobothrium nihonkaiense (cestoda: diphyllobothriidea), originally described from japan, is reported from a man in north america for the first time. species identification was based on sequences of ribosomal (partial 18s rrna) and mitochondrial (partial cytochrome c oxidase subunit i) genes of proglottids expelled from a czech tourist who ate raw pacific sockeye salmon (oncorhynchus nerka) from british columbia, canada. | 2008 | 18256421 |
| individual variation in migration speed of upriver-migrating sockeye salmon in the fraser river in relation to their physiological and energetic status at marine approach. | little research has examined individual variation in migration speeds of pacific salmon (oncorhynchus spp.) in natural river systems or attempted to link migratory behavior with physiological and energetic status on a large spatial scale in the wild. as a model, we used three stocks of summer-run sockeye salmon (oncorhynchus nerka) from the fraser river watershed, british columbia, to test the hypothesis that individual variation in migration speed is determined by a combination of environmental ... | 2008 | 18419519 |
| historical analysis of salmon-derived polychlorinated biphenyls (pcbs) in lake sediments. | several recent studies have highlighted the importance of salmon as a means to deliver biomagnifying contaminants to nursery lakes. there is a lack of studies, however, which demonstrate empirically how this source has varied through time. this is of great significance because past salmon-derived contaminant loading was potentially greater than it is today. by analyzing radiometrically dated sediment cores collected from ten lakes in alaska and british columbia (b.c.), we relate historical numbe ... | 2009 | 19162299 |
| mechanisms influencing the timing and success of reproductive migration in a capital breeding semelparous fish species, the sockeye salmon. | two populations of homing sockeye salmon (oncorhynchus nerka; adams and chilko) were intercepted in the marine approaches around the northern and southern ends of vancouver island (british columbia, canada) en route to a natal river. more than 500 salmon were nonlethally biopsied for blood plasma, gill filament tips, and gross somatic energy (gse) and were released with either acoustic or radio transmitters. at the time of capture, gse, body length, and circulating testosterone ([t]) differed be ... | 2009 | 19780650 |
| gene expression profiling and environmental contaminant assessment of migrating pacific salmon in the fraser river watershed of british columbia. | the health and physiological condition of anadromous salmon is of concern as their upriver migration requires navigation of human-impacted waterways and metabolism of stored energy reserves containing anthropogenic contaminants. such factors may affect reproductive success of fish stocks. this study investigates chemical contaminant burdens and select gene expression profiles in pacific sockeye (oncorhynchus nerka) and chinook (oncorhynchus tshawytscha) salmon which traverse the fraser river wat ... | 2010 | 19811841 |
| salmon spawning migration: metabolic shifts and environmental triggers. | a large-scale functional genomics study revealed shifting metabolic processes in white muscle during the final 1300 km migration of wild sockeye salmon to their spawning grounds in the fraser river, british columbia. in 2006, lower adams stock sockeye salmon ceased feeding after passing the queen charlotte islands, 850 km from the fraser river. enhanced protein turnover and reduced transcription of actin, muscle contractile and heme-related proteins were early starvation responses in saltwater. ... | 2009 | 20403740 |
| physiological, energetic and behavioural correlates of successful fishway passage of adult sockeye salmon oncorhynchus nerka in the seton river, british columbia. | electromyogram (emg) radio telemetry was used in conjunction with physiological biopsy to relate prior physiological condition and subsequent swimming energetics and behaviours to passage success of 13 wild adult sockeye salmon oncorhynchus nerka at a vertical-slot fishway on the seton river, british columbia. at the time of capture, plasma lactate, glucose and cortisol levels indicated that fish were not exhibiting unusually high levels of physiological stress. very few differences existed betw ... | 2009 | 20735634 |
| Transcriptomics of environmental acclimatization and survival in wild adult Pacific sockeye salmon (Oncorhynchus nerka) during spawning migration. | Environmental shifts accompanying salmon spawning migrations from ocean feeding grounds to natal freshwater streams can be severe, with the underlying stress often cited as a cause of increased mortality. Here, a salmonid microarray was used to characterize changes in gene expression occurring between ocean and river habitats in gill and liver tissues of wild migrating sockeye salmon (Oncorhynchus nerka Walbaum) returning to spawn in the Fraser River, British Columbia, Canada. Expression profile ... | 2011 | 21951593 |
| parental identity influences progeny responses to incubation thermal stress in sockeye salmon onchorhynchus nerka. | the influence of individual parentage on progeny responses to early developmental temperature stress was examined in a cross-fertilization experiment using sockeye salmon oncorhynchus nerka. differences in survival, hatch timing and size were examined among five paternally linked and five maternally linked offspring families (weaver creek population, british columbia, canada) incubated at 12, 14 and 16° c from just after fertilization to hatch. mean embryonic survival was significantly lower at ... | 2012 | 22268440 |
| resurrecting an extinct salmon evolutionarily significant unit: archived scales, historical dna and implications for restoration. | archival scales from 603 sockeye salmon (oncorhynchus nerka), sampled from may to july 1924 in the lower columbia river, were analysed for genetic variability at 12 microsatellite loci and compared to 17 present-day o. nerka populations-exhibiting either anadromous (sockeye salmon) or nonanadromous (kokanee) life histories-from throughout the columbia river basin, including areas upstream of impassable dams built subsequent to 1924. statistical analyses identified four major genetic assemblages ... | 2012 | 22221423 |
| piscine reovirus, but not jaundice syndrome, was transmissible to chinook salmon, oncorhynchus tshawytscha (walbaum), sockeye salmon, oncorhynchus nerka (walbaum), and atlantic salmon, salmo salar l. | a jaundice syndrome occurs sporadically among sea-pen-farmed chinook salmon in british columbia, the westernmost province of canada. affected salmon are easily identified by a distinctive yellow discolouration of the abdominal and periorbital regions. through traditional diagnostics, no bacterial or viral agents were cultured from tissues of jaundiced chinook salmon; however, piscine reovirus (prv) was identified via rt-rpcr in all 10 affected fish sampled. by histopathology, jaundice syndrome i ... | 2016 | 25630226 |
| recreational anglers' attitudes, beliefs, and behaviors related to catch-and-release practices of pacific salmon in british columbia. | the fate of captured and released fish in recreational fisheries depends in large part on fisher handling and behavior. as such, there is a need for promoting adoption of responsible fishing practices. we interviewed recreational sockeye salmon anglers in the lower fraser river, british columbia, to assess their awareness of responsible fishing practices and identify gaps where improved education could promote conservation-oriented behaviors. based on our interview data, we developed three laten ... | 2013 | 23872215 |
| using grizzly bears to assess harvest-ecosystem tradeoffs in salmon fisheries. | implementation of ecosystem-based fisheries management (ebfm) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. we address this social-ecological need for pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. we used grizzly bears, vectors of salmon nutrients and animal ... | 2012 | 22505845 |
| myxobolus arcticus and parvicapsula minibicornis infections in sockeye salmon oncorhynchus nerka following downstream migration in british columbia. | factors influencing the health of sockeye salmon oncorhynchus nerka in british columbia, canada, are important for fisheries management and conservation. juvenile salmon originating from the fraser river were screened for 3 enzootic parasites (myxobolus arcticus, parvicapsula minibicornis, ceratonova shasta) and the bacterium renibacterium salmoninarum. fish were collected from the strait of georgia in 2010, 2011 and 2012 and genotyped to stock of origin. trends in infection status were estimate ... | 2017 | 29044039 |