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British Columbia (british + columbia)
Kinds of British Columbia Selected AbstractsConservation Status as a Biodiversity Trend Indicator: Recommendations from a Decade of Listing Species at Risk in British ColumbiaCONSERVATION BIOLOGY, Issue 4 2005JAMES F. QUAYLE especies amenazadas; especies en peligro; estado del ambiente Abstract:,Species conservation status is commonly used as a broad-scale indicator of the state of biological diversity. To learn about its value for tracking trends, we examined provincial lists of terrestrial vertebrate species and subspecies at risk in British Columbia, Canada, for 1992 and 2002 to see whether changes in these lists reflected changes in the status of the taxa they represent. Examination of the case histories of individual species and subspecies showed that 65% of additions and deletions to the British Columbia Red List were the result of improvement in knowledge of species status, changes in assessment procedures, and refinements in taxonomy rather than actual changes in a species' status. Comparison to an alternate set of rank scores provided by NatureServe for taxa that appeared on both 1992 and 2002 British Columbia Red Lists revealed changes in status that were not reflected by movement from the list. Estimates of historical conservation status for species on the 1992 British Columbia Red List demonstrated ambiguity around the natural baseline with regard to tracking changes in list composition over time. We discourage the continued use of indicators based solely on conservation status as a means of tracking biodiversity. Instead we recommend advancing strategic indicators around species at risk based on long-term monitoring data, deliberate and explicitly stated baselines, and consistent methods of conservation ranking. Resumen:,El estatus de conservación de las especies comúnmente es utilizado como un indicador de escala amplia del estado de la diversidad biológica. En un esfuerzo por aprender sobre su valor para el seguimiento de tendencias, examinamos listas provinciales, para 1992 y 2002, de especies y subespecies de vertebrados terrestres en riesgo en Columbia Británica, Canadá, para ver si los cambios en estas listas reflejaban cambios en el estatus de los taxa que representan. El examen de la historia del caso de especies y subespecies individuales mostró que 65% de las adiciones y supresiones en la Lista Roja de Columbia Británica fueron el resultado de avances en el conocimiento del estatus de la especie, de cambios en los procedimientos de evaluación y de refinamientos en la taxonomía y no de cambios en el estatus de una especie. La comparación con un conjunto alternativo de valores de clasificación proporcionado por NatureServe para taxa que aparecieron tanto en la Lista Roja de Columbia Británica de 1992 como de 2002 reveló cambios en el estatus que no se reflejaron en movimientos en la lista. Estimaciones del estatus de conservación histórico de especies en la Lista Roja de Columbia Británica de 1992 demostraron ambigüedad alrededor de la línea de base natural en relación con el seguimiento de cambios en el tiempo en la composición de la lista. Desalentamos el uso continuo de indicadores basados solamente en el estatus de conservación como un medio para el seguimiento de biodiversidad. En cambio, recomendamos avanzar con indicadores estratégicos en torno a especies en riesgo con base en datos de monitoreo de largo plazo, en líneas básicas puestas de manifiesto deliberada y explícitamente y en métodos consistentes para la clasificación de la conservación. [source] Psychosis and offending in British Columbia: characteristics of a secure hospital populationCRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 3 2001Nicola Hodelet Specialist Registrar Introduction There is an increased likelihood of violence in the mentally ill although the risk is small. Aims The study aimed to ascertain the features in a secure hospital population that linked offending and mental illness. Method A survey of patients in the high security hospital serving the province of British Columbia in Canada was carried out. Information on 175 mentally disordered offenders was extracted and included demographic data and specific characteristics of their offences, diagnoses and psychotic symptoms. Results The most prevalent offences were crimes of violence, but 39% of patients were not primarily violent offenders. Almost two-thirds (61%) had two or more diagnoses. A large majority of the patients were psychotic, schizophrenia being the most common diagnosis. There was a highly significant association between psychosis and violence, but the strength of the association was not increased by the presence of imperative hallucinations or delusions. The sample comprised various ethnic groups, one of which, Native Americans, was over-represented. However, no association was found between violent offending and ethnicity, or age or years of illness. Discussion The study replicates previous findings of the link between violent offending and psychosis, but not a specific link between violent offending and psychotic drive. A surprising finding was a lack of association between violent offences and substance misuse. Copyright © 2001 Whurr Publishers Ltd. [source] A Secondary School Career Education Program for ESL StudentsCURRICULUM INQUIRY, Issue 4 2001June Wyatt-Beynon Using Bourdieu's theory of different types of capital and social "fields," this paper analyzes one curriculum model, the ESL Co-op program, which is designed to meet the needs of immigrant adolescents who are primarily dependent on their first language. The program couples instruction in English as a second language (ESL) with work experience. ESL Co-op is offered in two secondary schools in a suburban Vancouver school district that is the most rapidly growing district in British Columbia. More than 30 percent of the approximately 50,000 students enrolled in the district speak a language other than, or in addition to, English in the home. A collaborative team of university researchers and district curriculum consultants inquired into the program's success in helping recent immigrant students become aware of possible future career and job opportunities and any other aspects of the program's operation deemed salient by the interviewees. We wondered if the folk theory of success embedded in federal, provincial, and district policy discourse, which emphasizes work experience, was in fact setting the stage for educational and occupational success of these young people. Interviews with 44 parents, 43 students, and six staff members from a total of 10 different language backgrounds revealed that staff perceive the program as a unique opportunity for students to gain exposure to Canadian work environments and to develop survival, language, and job-related skills or, in Bourdieu's terms, embodied capital. Students' and parents' overriding concern is that the program precludes the possibility of graduation with the grade-12 diploma (institutional capital) available from the mainstream program. [source] Medication decisions and clinical outcomes in the Canadian National Outcomes Measurement Study in SchizophreniaACTA PSYCHIATRICA SCANDINAVICA, Issue 2006R. Williams Objective:, To evaluate over a 2-year period, patients from academic/non-academic centres, from each region of Canada, to determine whether location or other variables such as medication type, gender or income was associated with outcome as defined by non-hospitalization and persistence on original treatment. Method:, A total of 448 patients were recruited from academic and non-academic centres across all provinces of Canada and followed up for 2 years. Results:, Patients from British Columbia had significantly lower rates of hospitalization than patients from other provinces. Male patients showed greater symptomatic improvement at 2 years from initial assessment compared to females. Patients on clozapine, risperidone and olanzapine were least likely to be hospitalized. Conclusion:, There were some regional differences noted in both utilization of types of antipsychotic medications and hospitalization rates. In this sample of stable out-patients over 70% who started on monotherapy with clozapine, risperidone, olanzapine and quetiapine remained on the same medication over the 2-year study period. [source] First record of the brachiopod Lingulella waptaensis with pedicle from the Middle Cambrian Burgess ShaleACTA ZOOLOGICA, Issue 2 2010Sandra Pettersson Stolk Abstract Pettersson Stolk, S., Holmer, L. E. and Caron, J -B. 2010. First record of the brachiopod Lingulella waptaensis with pedicle from the Middle Cambrian Burgess Shale. ,Acta Zoologica (Stockholm) 91: 150,162 The organophosphatic shells of linguloid brachiopods are a common component of normal Cambrian,Ordovician shelly assemblages. Preservation of linguloid soft-part anatomy, however, is extremely rare, and restricted to a few species in Lower Cambrian Konservat Lagerstätten. Such remarkable occurrences provide unique insights into the biology and ecology of early linguloids that are not available from the study of shells alone. Based on its shells, Lingulella waptaensis Walcott, was originally described in 1924 from the Middle Cambrian Burgess Shale but despite the widespread occurrence of soft-part preservation associated with fossils from the same levels, no preserved soft parts have been reported. Lingulella waptaensis is restudied herein based on 396 specimens collected by Royal Ontario Museum field parties from the Greater Phyllopod Bed (Walcott Quarry Shale Member, British Columbia). The new specimens, including three with exceptional preservation of the pedicle, were collected in situ in discrete obrution beds. Census counts show that L. waptaensis is rare but recurrent in the Greater Phyllopod Bed, suggesting that this species might have been generalist. The wrinkled pedicle protruded posteriorly between the valves, was composed of a central coelomic space, and was slender and flexible enough to be tightly folded, suggesting a thin chitinous cuticle and underlying muscular layers. The nearly circular shell and the long, slender and highly flexible pedicle suggest that L. waptaensis lived epifaunally, probably attached to the substrate. Vertical cross-sections of the shells show that L. waptaensis possessed a virgose secondary layer, which has previously only been known from Devonian to Recent members of the Family Lingulidae. [source] Postglacial topographic evolution of glaciated valleys: a stochastic landscape evolution modelEARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2005Simon J. Dadson Abstract The retreat of valley glaciers has a dramatic effect on the stability of glaciated valleys and exerts a prolonged influence on the subsequent fluvial sediment transport regime. We have studied the evolution of an idealized glaciated valley during the period following retreat of ice using a numerical model. The model incorporates a stochastic process to represent deep-seated landsliding, non-linear diffusion to represent shallow landsliding and an approximation of the Bagnold relation to represent fluvial sediment transport. It was calibrated using field data from several recent surveys within British Columbia, Canada. We present ensemble model results and compare them with results from a deterministic linear-diffusion model to show that explicit representation of large landslides is necessary to reproduce the morphology and channel network structure of a typical postglacial valley. Our model predicts a rapid rate of fluvial sediment transport following deglaciation with a subsequent gradual decline, similar to that inferred for Holocene time. We also describe how changes in the model parameters affect the estimated magnitude and duration of the paraglacial sediment pulse. Copyright © 2005 John Wiley & Sons, Ltd. [source] Testing bedload transport formulae using morphologic transport estimates and field data: lower Fraser River, British ColumbiaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2005Yvonne Martin Abstract Morphologic transport estimates available for a 65-km stretch of Fraser River over the period 1952,1999 provide a unique opportunity to evaluate the performance of bedload transport formulae for a large river over decadal time scales. Formulae tested in this paper include the original and rational versions of the Bagnold formula, the Meyer-Peter and Muller formula and a stream power correlation. The generalized approach adopted herein does not account for spatial variability in flow, bed structure and channel morphology. However, river managers and engineers, as well as those studying rivers within the context of long-term landscape change, may find this approach satisfactory as it has minimal data requirements and provides a level of process specification that may be commensurable with longer time scales. Hydraulic geometry equations for width and depth are defined using morphologic maps based on aerial photography and bathymetric survey data. Comparison of transport predictions with bedload transport measurements completed at Mission indicates that the original Bagnold formula most closely approximates the main trends in the field data. Sensitivity analyses are conducted to evaluate the impact of inaccuracies in input variables width, depth, slope and grain size on transport predictions. The formulae differ in their sensitivity to input variables and between reaches. Average annual bedload transport predictions for the four formulae show that they vary between each other as well as from the morphologic transport estimates. The original Bagnold and Meyer-Peter and Muller formulae provide the best transport predictions, although the former underestimates while the latter overestimates transport rates. Based on our findings, an error margin of up to an order of magnitude can be expected when adopting generalized approaches for the prediction of bedload transport. Copyright © 2005 John Wiley & Sons, Ltd. [source] Geomorphic and sedimentological signature of a two-phase outburst ,ood from moraine-dammed Queen Bess Lake, British Columbia, CanadaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 1 2005Jane A. Kershaw Abstract On 12 August 1997, the lower part of Diadem Glacier in the southern Coast Mountains of British Columbia fell into Queen Bess Lake and produced a train of large waves. The waves overtopped the broad end moraine at the east end of the lake and ,ooded the valley of the west fork of Nostetuko River. The displacement waves also incised the out,ow channel across the moraine. Stratigraphic and sedimentologic evidence supports the conclusion that the ,ood had two phases, one related to wave overtopping and a second to breach formation. Empirical equations were used to calculate the peak discharge of the ,ood at various points along the west fork of the Nostetuko valley and to describe the attenuation of the ,ood wave. The velocity of the ,ood was also calculated to determine the time it took for the ,ood to reach the main fork of Nostetuko River. The highest peak discharges were achieved in the upper reach of the valley during the displacement phase of the ,ood. Peak discharge declined rapidly just below the moraine dam, with little change thereafter for approximately 7 km. Empirical formulae and boulder measurements indicate a rise in peak discharge in the lower part of the west fork valley. We suggest that ,ow in the upper part of the valley records the passage of two separate ,ood peaks and that the rise in discharge in the lower part of the valley is due to amalgamation of the wave and breach peaks. Hydraulic ponding in con,ned reaches of the valley extended the duration of the ,ood. In addition, erosion of vegetation and sediment in the channel and valley sides may also have exerted an in,uence on the duration and nature of ,ooding. Sediments were deposited both upstream and downstream of channel constrictions and on a large fan extending out into the trunk Nostetuko River valley. This study extends our understanding of the variety and complexity of outburst ,oods from naturally dammed lakes. It also shows that simple empirical and other models for estimating peak discharges of outburst ,oods are likely to yield erroneous results. Copyright © 2005 John Wiley & Sons, Ltd. [source] Analysis of landslide frequencies and characteristics in a natural system, coastal British ColumbiaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 11 2004R. H. Guthrie Abstract Two hundred and one debris slides and debris ,ows were analyzed in a 286 km2 study area on the west coast of Vancouver Island, British Columbia, Canada. The study area remains essentially untouched by humans and therefore affords a natural setting in which to examine slope processes. Landslides were identi,ed and characterized on aerial photographs from 1:15 000 to 1:31 680, and were then mapped and transferred to a GIS for analysis. Based on detailed landslide surveys, we propose a new method to accurately determine volume of landslides of this type by measured total area. Results indicate average denudation rates of 56 m3 y,1 km,2, and higher natural rates of failure than analogous regions in coastal British Columbia. In contrast, the landslide rates are substantially less than those from forested watersheds. Landslide distribution is spatially clustered in air photograph epochs, and we propose intense storm cells within regional events as the causal mechanism. Further, failures occurred preferentially over the West Coast Crystalline Complex (by 1·4 times), a metamorphic assemblage of gabbros, schists and amphibolites, but 1·5 times less often over the Island Plutonic Suite, a granitic intrusive formation. The former result represents a new ,nding, while the latter corroborates ,ndings of previous authors. We examined magnitude,frequency relationships of the data set and present for the ,rst time a strong argument that the rollover effect is not merely an artefact, but is instead a consequence of the physical characteristics of the landslides themselves. We subsequently analyzed magnitude,frequency relationships from two other complete data sets from coastal British Columbia and produced a family of curves corroborating this result. Copyright © 2004 John Wiley & Sons, Ltd. [source] Measurement of the spatial distribution of fluvial bedload transport velocity in both sand and gravelEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2004Colin D. Rennie Abstract Maps are presented of the spatial distribution of two-dimensional bedload transport velocity vectors. Bedload velocity data were collected using the bottom tracking feature of an acoustic Doppler current pro,ler (aDcp) in both a gravel-bed reach and a sand-bed reach of Fraser River, British Columbia. Block-averaged bedload velocity vectors, and bedload velocity vectors interpolated onto a uniform grid, revealed coherent patterns in the bedload velocity distribution. Concurrent Helley-Smith bedload sampling in the sand-bed reach corroborated the trends observed in the bedload velocity map. Contemporaneous 2D vector maps of near-bed water velocity (velocity in bins centered between 25 cm and 50 cm from the bottom) and depth-averaged water velocity were also generated from the aDcp data. Using a vector correlation coef,cient, which is independent of the choice of coordinate system, the bedload velocity distribution was signi,cantly correlated to the near-bed and depth-averaged water velocity distributions. The bedload velocity distribution also compared favorably with variations in depth and estimates of the spatial distribution of shear stress. Published in 2004 by John Wiley & Sons, Ltd. [source] Interchannel hydraulic geometry and hydraulic efficiency of the anastomosing Columbia River, southeastern British Columbia, CanadaEARTH SURFACE PROCESSES AND LANDFORMS, Issue 8 2003Kevin K. Tabata Abstract The morphodynamics of the anastomosing channel system of upper Columbia River in southeastern British Columbia, Canada, is examined using an adaptation of conventional hydraulic geometry termed ,interchannel hydraulic geometry'. Interchannel hydraulic geometry has some of the characteristics of downstream hydraulic geometry but differs in that it describes the general bankfull channel form and hydraulics of primary and secondary channels in the anastomosing channel system. Interchannel hydraulic geometry generalizes these relationships and as such becomes a model of the geomorphology of channel division and combination. Interchannel hydraulic geometry of upper Columbia River, based on ,eld measurements of ,ow velocity and channel form at 16 test sections, is described well by simple power functions: wbf = 3·24Qbf0·64; dbf = 1·04Qbf0·19; vbf = 0·30Qbf0·17. These results, with other related measurements of ,ow resistance, imply that channel splitting leads to hydraulic inef,ciency (higher ,ow resistance) on the anastomosing Columbia River. Because these ,ndings differ from those reported in studies elsewhere, we conclude that hydraulic ef,ciency does not provide a general explanation for anabranching in river channels. Copyright © 2003 John Wiley & Sons, Ltd. [source] Empirical support for a multi-dimensional model of sensations experienced by youth during their initial smoking episodesADDICTION, Issue 10 2010Chris G. Richardson ABSTRACT Aims To examine the dimensionality of sensations experienced during initial tobacco smoking. Design Cross-sectional survey. Setting Thirteen secondary schools located in British Columbia, Canada. Participants Data from 1187 adolescents who responded ,yes' to the question: ,Have you ever tried cigarette smoking, even one or two puffs?'. Measurements Participants answered questions about their demographic characteristics, tobacco smoking history and sensations experienced during their initial smoking episodes. Findings The sensations appear to represent the following three separate but modestly correlated dimensions: a pleasant dimension defined by feeling good and relaxed; an unpleasant dimension defined by coughing, feeling sick and nervous; and a ,buzz' dimension defined by feeling high and dizzy. The three factors made statistically significant contributions to the prediction of transition to regular smoking (defined as having smoked at least 100 cigarettes in one's life-time) after adjusting for age, sex and age at first puff. Conclusions The results suggest that three relatively distinct physiological systems appear to explain the relationship between initial smoking sensations and probability of becoming a regular smoker. Researchers examining sensations experienced during initial tobacco smoking episodes should consider using a three-dimensional profile of symptoms composed of pleasant, unpleasant and buzz dimensions. [source] A multi-scale test for dispersal filters in an island plant communityECOGRAPHY, Issue 4 2005Kevin C. Burns Constraints on plant distributions resulting from seed limitation (i.e. dispersal filters) were evaluated on two scales of ecological organization on islands off the coast of British Columbia, Canada. First, island plant communities were separated into groups based on fruit morphology, and patterns in species diversity were compared between fruit-type groups. Second, abundance patterns in several common fleshy-fruited, woody angiosperm species were compared to species-specific patterns in seed dispersal by birds. Results from community-level analyses showed evidence for dispersal filters. Dry-fruited species were rare on islands, despite being common on the mainland. Island plant communities were instead dominated by fleshy-fruited species. Patterns in seed dispersal were consistent with differences in diversity, as birds dispersed thousands of fleshy-fruited seeds out to islands, while dry fruited species showed no evidence of mainland-island dispersal. Results from population-level analyses showed no evidence for dispersal filters. Population sizes of common fleshy-fruited species were unrelated to island isolation, as were rates of seed dispersal. Therefore, island isolation distances were not large enough to impose constraints on species' distributions resulting from seed limitation. Rates of seed dispersal were also unrelated to island area. However, several species increased in abundance with island area, indicating post-dispersal processes also help to shape species distributions. Overall results suggest that seed dispersal processes play an important role in determining the diversity and distribution of plants on islands. At the community-level, dry-fruited species were seed limited and island communities were instead dominated by fleshy-fruited species. At the population-level, common fleshy-fruited species were not seed limited and showed few differences in distribution among islands. Therefore, although evidence for dispersal filters was observed, their effects on plant distributions were scale-dependent. [source] Ground beetle responses to patch retention harvesting in high elevation forests of British ColumbiaECOGRAPHY, Issue 5 2004Jeffrey P. Lemieux The effect of a forest harvesting system whereby small (typically 0.1,2.0 ha) patches of standing timber are retained inside of harvests, was compared to conventional clearcutting for its effect on ground beetle assemblages. Two seasons of pitfall trapping entailed 46,451 trap days, and yielded 15,799 individuals of 28 species; abundance was dominated by four species comprising 92.4% of the catch. Most species were known to have wide geographic distributions in Canada and Alaska but many species seemed to respond to disturbance on a site-specific basis. Contrary to findings of similar studies, no species could be characterized as "mature-forest specialists", or "forest generalists". Forest patches and edge habitats immediately inside the forest canopy contained assemblages more closely related to mature forest than to cleared areas. Harvested areas with patches yielded catches distinct from typical clearcuts, based primarily on changes in abundance of one common species. Climatic regimes and landscape disturbance levels were the two important factors distinguishing our study from others, and we have suggested that these may influence the degree to which patches are an effective conservation tool. [source] Burying beetle Nicrophorus investigator reproduction on Pacific salmon carcassesECOLOGICAL ENTOMOLOGY, Issue 1 2006M. D. Hocking Abstract., 1.,In many undisturbed watersheds along the Pacific Rim, anadromous salmon (Oncorhynchus spp.) provide a predictable source of carrion to the riparian zone, largely due to horizontal transfer of salmon carcasses by bears (Ursus spp.) and other vertebrates. 2.,Burying beetles are important members of the north-temperate carrion fauna, and may utilise salmon carcasses and remnants for breeding. In this study, isotopic and observational data are reported that demonstrate previously unrecognised Nicrophorus investigator (Zetterstedt) reproduction on large salmon carcasses from five watersheds in coastal British Columbia. 3.,Stable isotope signatures (,15N and ,13C) of adult beetles collected in autumn indicate a diet of salmon origin in all but one individual from all watersheds, suggesting that this beetle,salmon association is widespread. Comparison of autumn isotope signatures to individuals collected randomly in summer suggests that isotope signatures represent the larval carrion source from the previous autumn rather than immediate adult diet. 4.,In a survey of N. investigator use of salmon carcasses from two watersheds, 35 broods were observed on chum and pink salmon carcasses, including 16 natural brood complexes containing over 100 larvae, and five ranging from 250 to 750 larvae. 5.,Overall, north-coastal populations of N. investigator breed on the rich and reliable salmon resource and may exhibit a system of communal breeding on these carcasses. This is most relevant when the dramatic reduction in salmon spawning biomass over the last century is considered. [source] Crossing Cultures, Learning to Export: Making Houses in British Columbia for Consumption in Japan,ECONOMIC GEOGRAPHY, Issue 2 2002Tim Reiffenstein Abstract: In this article, trade is conceptualized as a cultural as well as an economic and political process. In this view, exporting connects market intelligence with production intelligence on either side of national, typically cultural, borders. These connections frequently imply alternative, mutually influencing, forms of communication and learning that have various implications for local development. A model of relational market intelligence is outlined as a way of understanding this dimension of exporting. The model integrates production and market intelligence while emphasizing alternative pathways of learning and communication. It is applied to the newly emergent trade that features the export of houses from British Columbia to Japan. Within an extended case-study research design framework, information is based on interviews with manufacturing firms and related organizations in British Columbia. Implications for local development in British Columbia are noted. [source] Addiction research centres and the nurturing of creativity: The Centre for Addictions Research of British Columbia, CanadaADDICTION, Issue 2 2010Tim Stockwell ABSTRACT The Centre for Addictions Research of British Columbia (CARBC) was established as a multi-campus and multi-disciplinary research centre administered by the University of Victoria (UVic) in late 2003. Its core funding is provided from interest payments on an endowment of CAD$10.55 million. It is supported by a commitment to seven faculty appointments in various departments at UVic. The Centre has two offices, an administration and research office in Victoria and a knowledge exchange unit in Vancouver. The two offices are collaborating on the implementation of CARBC's first 5-year plan which seeks to build capacity in British Columbia for integrated multi-disciplinary research and knowledge exchange in the areas substance use, addictions and harm reduction. Present challenges include losses to the endowment caused by the 2008/2009 economic crisis and difficulties negotiating faculty positions with the university administration. Despite these hurdles, to date each year has seen increased capacity for the Centre in terms of affiliated scientists, funding and staffing as well as output in terms of published reports, electronic resources and impacts on policy and practice. Areas of special research interest include: drug testing in the work-place, epidemiological monitoring, substance use and injury, pricing and taxation policies, privatization of liquor monopolies, polysubstance use, health determinants of indigenous peoples, street-involved youth and other vulnerable populations at risk of substance use problems. Further information about the Centre and its activities can be found on http://www.carbc.ca. [source] Changes in per capita alcohol sales during the partial privatization of British Columbia's retail alcohol monopoly 2003,2008: a multi-level local area analysisADDICTION, Issue 11 2009Tim Stockwell ABSTRACT Aim To investigate the independent effects on liquor sales of an increase in (a) the density of liquor outlets and (b) the proportion of liquor stores in private rather than government ownership in British Columbia between 2003/4 and 2007/8. Design The British Columbia Liquor Distribution Branch provided data on litres of ethanol sold through different types of outlets in 89 local health areas of the province by beverage type. Multi-level regression models were used to examine the relationship between per capita alcohol sales and outlet densities for different types of liquor outlet after adjusting for potential confounding social, economic and demographic factors as well as spatial and temporal autocorrelation. Setting Liquor outlets in 89 local health areas of British Columbia, Canada. Findings The number of private stores per 10 000 residents was associated significantly and positively with per capita sales of ethanol in beer, coolers, spirits and wine, while the reverse held for government liquor stores. Significant positive effects were also identified for the number of bars and restaurants per head of population. The percentage of liquor stores in private versus government ownership was also associated significantly with per capita alcohol sales when controlling for density of liquor stores and of on-premise outlets (P < 0.01). Conclusion The trend towards privatisation of liquor outlets between 2003/04 and 2007/08 in British Columbia has contributed to increased per capita sales of alcohol and hence possibly also to increased alcohol-related harm. [source] Environmental concentrations of methoprene and its transformation products after the treatment of Altosid® XR Briquets in the city of Richmond, British Columbia, CanadaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2010Jen-ni Kuo Abstract Water runoff from catch basins treated with Altosid® XR Briquets for mosquito larvae control was sampled at 10 storm drainage pump stations along the outskirts of the city of Richmond, British Columbia, Canada after rainfall events in 2006 to determine the residual concentrations of methoprene and transformation products: citronellic acid, methoprene acid, and 7-methoxycitronellic acid. Runoff of prior-to-treatment, posttreatment, and 150-d-after-treatment was collected. No residues were detected in the prior-to-treatment samples. However, methoprene was detected in posttreatment, and citronellic acid was detected in posttreatment and one 150-d-after-treatment sample. The detected environmental concentrations of methoprene (0.04,0.14,µg/L) and methoprene acid (0.07,µg/L) at pump stations were below known/reported toxicity values to aquatic organisms. However, concentrations detected inside the storm drainage system in catch basins (methoprene 122,µg/L, methoprene acid 1.74,µg/L) and inspection chambers (methoprene 622,µg/L, methoprene acid 20,µg/L, citronellic acid 0.05,µg/L) are known to be toxic to invertebrates, have chronic early-life-stage fish effects, and exceeded the Draft Interim Ontario Water Quality Objective and the numerical benchmarks for protection of amphibians (1.6,µg/L), invertebrates (10,µg/L), and fish (80,µg/L). The limited detection in the present study may have resulted from significant absorption of methoprene to sample bottle walls, substance decay during sample storage before methoprene extraction, flushing of briquettes from catch basins following heavy rainfall, and the burial of briquettes under thick layers of debris. Environ. Toxicol. Chem. 2010;29:2200,2205. © 2010 SETAC [source] Dose-dependent uptake, elimination, and toxicity of monosodium methanearsonate in adult zebra finches (Taeniopygia guttata)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2008Courtney A. Albert Abstract Monosodium methanearsonate (MSMA), an arsenic-based pesticide, has been used for the past 10 years in attempts to suppress mountain pine beetle (Dendroctonus ponderosae) outbreaks in British Columbia, Canada. Previous studies have shown that cavity nesting forest birds such as woodpeckers forage and breed in MSMA treated pine stands. Here we examined the effects of MSMA in the laboratory using the zebra finch (Taeniopygia guttata), with the objective to examine tissue distribution and sublethal toxic effects in a model avian species. Zebra finches were exposed to this pesticide at doses similar to those found in bark beetle samples from MSMA stands of trees treated in the southern interior of British Columbia (8, 24, and 72 ,g/g/d and a control group). Results showed high excretion (>90%) of arsenic in all dose groups, as well as dose-dependent trends in accumulation of arsenic in the blood (p < 0.001) and specific tissues. Monomethylarsonic acid, MMA (V), was the predominant form of arsenic in the blood plasma. Dimethylarsinic acid was the major form of arsenic found in the liver (83%) and kidney (61%) tissues. The brain tissue contained primarily the MMA (V) form (57%). Significant weight loss occurred in the two highest dose groups (p < 0.05). Birds in the highest dose group lost up to 15% of initial body mass. [source] Emission of legacy chlorinated pesticides from agricultural and orchard soils in British Columbia, CanadaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2006Terry F. Bidleman Abstract Air samples were collected above agricultural fields in the Fraser Valley and orchards in the Okanagan Valley, British Columbia, Canada, to investigate volatilization of organochlorine pesticides used in the past. Concentrations of pesticides in air were elevated over soils that contained higher residues. Soil/air fugacity ratios at sites with the higher soil residues were calculated relative to air sampled at 40 cm height and background air. The fugacity ratios in the first case indicated net volatilization or soil-air equilibrium for most compounds and occasional net deposition for p,p, -dichlorodiphenyldichloroethene (p,p, -DDE), whereas those in the second case showed a strong potential for net volatilization of all compounds. The enantiomer fraction (EF) of chiral compounds ,-hexachlorocyclohexane (,-HCH), trans -chlordane, cis -chlordane, and o,p, -DDT were determined in overlying air samples and soils. Enantiomer fractions in air corresponded to those in soils at fields in which soil concentrations were high but were decoupled from soil signatures at fields with low soil residues. Mean EFs in air sampled over soils were significantly (p < 0.001) nonracemic for ,-HCH and the chlordanes and agreed with published EFs in regional ambient air. The mean EF of o,p, -DDT for all air samples did not show a significant deviation from racemic EFs (p > 0.2), but EFs of individual samples reflected the ambivalent nature of o,p, -DDT degradation, sometimes preferring the (+) enantiomer and other times the (,) enantiomer. The study indicates that soils are continuing to emit "legacy" pesticides into the regional atmosphere. [source] Trace metals, stable isotope ratios, and trophic relations in seabirds from the North Pacific OceanENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2005John E. Elliott Abstract Trace elements including mercury, cadmium, selenium, and stable nitrogen isotope ratios (,15N) were measured in tissues of Pacific seabirds. Two species of albatross (Diomedea immutabilis, Diomedea nigripes), four species of shearwaters (Puffinus bulleri, Puffinus carneipes, Puffinus griseus, Puffinus tenuirostris), northern fulmar (Fulmarus glacialis), and horned puffin (Fratercula corniculata) were collected opportunistically by an experimental fishery in the North Pacific Ocean. Two species each of petrels (Oceanodroma leucorhoa, Oceanodroma furcata) and auklets (Ptychoramphus aleuticus, Cerorhinca monocerata) were collected at breeding colonies on the north coast of British Columbia, Canada. Concentrations of toxic trace metals varied considerably among the pelagic nonbreeders; highest concentrations consistently were in D. nigripes (e.g., Hg), 70-fold greater than F. corniculata (e.g., Cd), eightfold greater than P. tenuirostris (e.g., Se), and fourfold greater than F. corniculata. Most essential trace elements varied little among species, consistent with physiological regulation. Values for ,15N correlated positively with hepatic Se (r = 0.771, p = 0.025) and negatively with Co (r = 0.817, p = 0.013). Among the four breeding species, there were significant positive associations for ,15N in muscle and hepatic Se (r = 0.822, p = 0.002), Hg (r = 0.744, p = 0.0001), and Cd (r = 0.589, p = 0.003). Differences in time scales integrated by ,15N versus trace metals in tissues probably reduced the apparent associations between trace-metal exposure and diet. [source] Association between lymphocyte proliferation and polychlorinated biphenyls in free-ranging harbor seal (Phoca vitulina) pups from British Columbia, CanadaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2005Milton Levin Abstract Recent pinniped die-offs have led to the speculation that persistent organic pollutants (POPs) are immunomodulatory, making individuals more susceptible to viral infections. Eighteen healthy harbor seal (Phoca vitulina) pups (aged 3,4 weeks) were live-captured from southern British Columbia, Canada, and maintained temporarily in captivity for an immunotoxicological assessment. The relationships between mitogen-induced peripheral blood lymphocyte proliferation and blubber concentrations of three major immunotoxic POP classes (the polychlorinated biphenyls [PCBs], polychlorinated dibenzo- p -dioxins [PCDDs], and the polychlorinated dibenzofurans [PCDFs]) were evaluated. A significant body weight-independent positive correlation was observed between both T-cell mitogen (phytohemagglutinin [PHA])- and B-cell mitogen (lipopolysaccharide [LPS])-induced lymphocyte proliferation and the blubber concentrations of total PCB. Best subset regression analysis revealed that total PCBs, and not total PCDD or total PCDF, explained 24 and 29% of the changes in both T-cell mitogen-and B-cell mitogen-induced lymphocyte proliferation, respectively. Further regression analysis performed on the PCB classes measured in this study showed that di - ortho PCBs accounted for 25 and 30% of the changes in both T-cell and B-cell lymphocyte proliferation, respectively. Results suggest that POPs, and PCBs in particular, are associated with changes in lymphocyte proliferation, something that could result in increased susceptibility to infections in harbor seal pups. Further research is needed to evaluate the relative roles of natural and contaminant-related influences on the immune system of marine mammals. [source] Assessing trace-metal exposure to American dippers in mountain streams of southwestern British Columbia, CanadaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2005Christy A. Morrissey Abstract To develop a suitable biomonitor of metal pollution in watersheds, we examined trends in exposure to nine trace elements in the diet (benthic invertebrates and fish), feathers (n = 104), and feces (n = 14) of an aquatic passerine, the American dipper (Cinclus mexicanus), from the Chilliwack watershed in British Columbia, Canada. We hypothesized that key differences may exist in exposure to metals for resident dippers that occupy the main river year-round and altitudinal migrants that breed on higher elevation tributaries because of differences in prey metal levels between locations or possible differences in diet composition. Metals most commonly detected in dipper feather samples in decreasing order were Zn > Cu > Hg > Se > Pb > Mn > Cd > Al > As. Resident dipper feathers contained significantly higher mean concentrations of mercury (0.64 ,g/g dry wt), cadmium (0.19 ,g/g dry wt), and copper (10.8 ,g/g dry wt) relative to migrants. Mass balance models used to predict daily metal exposure for dippers with different diets and breeding locations within a watershed showed that variation in metal levels primarily was attributed to differences in the proportion offish and invertebrates in the diet of residents and migrants. In comparing predicted metal exposure values to tolerable daily intakes (TDI), we found that most metals were below or within the range of TDI, except selenium, aluminum, and zinc. Other metals, such as cadmium, copper, and arsenic, were only of concern for dippers mainly feeding on insects; mercury was only of concern for dippers consuming high fish diets. The models were useful tools to demonstrate how shifts in diet and breeding location within a single watershed can result in changes in exposure that may be of toxicological significance. [source] Persistent organic pollutants in air and vegetation from the canadian rocky mountainsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2004Deborah A. Davidson Abstract The exchange of chlorinated organic pollutants between air and vegetation in cold, mountain environments was investigated through the extraction of coniferous vegetation and high-volume air samples collected from the Canadian Rocky Mountains during the summers of 1999 and 2000. Concentrations of several compounds in vegetation increased as temperatures decreased, whereas atmospheric concentrations were not related to temperature. Daily cycling of these compounds between air and vegetation as a result of diurnal temperature changes was not observed. Compared with concentrations in vegetation from the Canadian Rocky Mountains, plant samples from the western valley in British Columbia (Canada) showed higher pollutant levels. Chemical partitioning between vegetation and air was not correlated with temperature, indicating that air contamination is governed by long-range transport and not by local revolatilization events. Based on these observations, we show that both deposition at higher altitudes and long-range atmospheric transport influence chemical accumulation in vegetation from the Canadian Rocky Mountains. [source] Harbor seals (Phoca vitulina) in British Columbia, Canada, and Washington State, USA, reveal a combination of local and global polychlorinated biphenyl, dioxin, and furan signalsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2004Peter S. Ross Abstract The harbor seal (Phoca vitulina) can serve as a useful indicator of food web contamination by persistent organic pollutants (POPs) because of its high trophic level, wide distribution in temperate coastal waters of the Northern Hemisphere, and relative ease of capture. In 1996 through 1997, we live-captured 60 harbor seal pups from three regions, spanning remote (Queen Charlotte Strait, BC, Canada), moderately industrialized (Strait of Georgia, BC, Canada), and heavily industrialized (Puget Sound, WA, USA) marine basins straddling the Canada-United States border. Biopsy samples of blubber were taken and analyzed for congener-specific polychlorinated biphenyls (PCBs), polychlorinated dibenzo- p -dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) by using high-resolution gas chromatography-high-resolution mass spectrometry. Harbor seals in Puget Sound were heavily contaminated with PCBs, whereas seals from the Strait of Georgia had relatively high concentrations of PCDDs and PCDFs. Pattern evaluation and principal components analysis suggested that proximity to sources influenced the mixture to which seals were exposed, with those inhabiting more remote areas being exposed to lighter PCB congeners (those with lower Henry's law constant and KOW) that disperse more readily through atmospheric and other processes. Total toxic equivalents to 2,3,7,8-tetrachlorodibenzo- p -dioxin for the PCBs, PCDDs, and PCDFs suggest that Puget Sound seals are at greatest risk for adverse health effects, and that PCBs represent the class of dioxinlike contaminants of greatest concern at all sites. [source] Toxicity and chemistry of aspen wood leachate to aquatic life: Field studyENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2003Barry R. Taylor Abstract A dark, toxic leachate has been observed around woodpiles of trembling aspen (Populus tremuloides Michx.) cut in winter for pulp or structural lumber. We measured production of leachate from 18 m3 of harvestable aspen logs stacked in an open field near Dawson Creek, British Columbia, Canada. The logpile began producing leachate during the first winter thaw and continued to do so for the duration of the two-year study (mean, 250 L/collection). Aspen leachate was characterized by dark color, acidic pH (5.0-6.5), elevated conductivity (200-500 ,S/cm), high to very high biochemical oxygen demand (500-5,000 mg/L) and total organic carbon concentrations (500-2,000 mg/L), variable levels of phenolic compounds (2-27 mg/L), and low dissolved oxygen tensions (<2 mg/L). In tests with rainbow trout (Oncorhynchus mykiss), Daphnia magna, and luminescent bacteria, the leachate varied from weakly toxic (median lethal concentration, >10%) to very toxic (median lethal concentration, <1%). The volume of leachate generated by the logpile was correlated with total precipitation (rain or snow) since the last collection. Loads of chemical constituents or toxicity (lethal concentration × volume) in the leachate did not decline over the duration of the study. Less than 10% of the total mass of leachable material in the aspen logs was removed during two years of exposure. [source] Concentration dependency of biota-sediment accumulation factors for chlorinated dibenzo- p -dioxins and dibenzofurans in dungeness crab (Cancer magister) at marine pulp mill sites in British Columbia, CanadaENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2000Walter J. Cretney Abstract Biota-sediment accumulation factors (BSAFs) for some chlorinated dibenzo- p -dioxin and dibenzofuran congeners (PCDD/Fs) in Dungeness crab (Cancer magister) hepatopancreas and associated sediments are concentration independent as required by equilibrium partition models. In particular 2, 3, 7, 8-tetrachlorodibenzo- p -dioxin (2, 3, 7, 8-TCDD), 2, 3, 7, 8-tetrachlorodibenzofuran, the 2, 3, 7, 8-substituted pentachlorodibenzofurans, and the non-2, 3, 7, 8-hexachlorodibenzofurans (HxCDFs) seem to fall into this group. The BSAFs for other isomers exhibit significant, nonlinear variations with sediment or crab PCDD/F concentrations. For some of these other isomers (e.g., the non-2, 3, 7, 8 TCDDs and possibility the 2, 3, 7, 8-substituted HxCDFs), association of a variable fraction of the total present with soot carbon may provide a satisfactory explanation for the concentration behavior. For the HxCDDs we propose that the nonlinear concentration behavior may arise from the thermodynamic properties of fluids confined in hydrophobic voids within particulate and colloidal material produced by the pulp mills. The nonlinear relationship between BSAFs and PCDD/F concentrations greatly complicates prediction of the potential for dioxin and furan bioaccumulation in crabs and the formulation of sediment quality criteria. We provide a nonlinear equation relating toxic equivalency and sediment concentrations. [source] Seasonal confounding and residual correlation in analyses of health effects of air pollutionENVIRONMETRICS, Issue 4 2007Isabella R. Ghement Abstract To investigate the health effects of air pollution via a partially linear model, one must choose an appropriate amount of smoothing for accurate estimation of the linear pollution effects. This choice is complicated by the dependencies between the various covariates and by the potential residual correlation. Most existing approaches to making this choice are inadequate, as they neither target accurate estimation of the linear pollutant effects nor handle residual correlation. In this paper, we illustrate two new adaptive and objective methods for determining an appropriate amount of smoothing. We construct valid confidence intervals for the linear pollutant effects, intervals that account for residual correlation. We use our inferential methods to investigate the same-day effects of PM10 on daily mortality in two data sets for the period 1994 to 1996: one collected in Mexico City, an urban area with high levels of air pollution, and the other collected in Vancouver, British Columbia, an urban area with low levels of air pollution. For Mexico City, our methodology does not detect a PM10 effect. In contrast, for Vancouver, a PM10 effect corresponding to an expected 2.4% increase (95% confidence interval ranging from 0.0% to 4.7%) in daily mortality for every 10,µg/m3 increase in PM10 is identified. Copyright © 2006 John Wiley & Sons, Ltd. [source] Changes in Canadian heroin supply coinciding with the Australian heroin shortageADDICTION, Issue 5 2006Evan Wood ABSTRACT Aims Previous studies have largely attributed the Australian heroin shortage to increases in local law enforcement efforts. Because western Canada receives heroin from similar source nations, but has not measurably increased enforcement practices or funding levels, we sought to examine trends in Canadian heroin-related indices before and after the Australian heroin shortage, which began in approximately January 2001. Methods During periods before and after January 2001, we examined the number of fatal overdoses and ambulance responses to heroin-related overdoses that required the use of naloxone in British Columbia, Canada. As an overall marker of Canadian supply reduction, we also examined the quantity of heroin seized during this period. Lastly, we examined trends in daily heroin use among injection drug users enrolled in the Vancouver Injection Drug Users Study (VIDUS). Results There was a 35% reduction in overdose deaths, from an annual average of 297 deaths during the years 1998,2000 in comparison to an average of 192 deaths during 2001,03. Similarly, use of naloxone declined 45% in the period coinciding with the Australian heroin shortage. Interestingly, the weight of Canadian heroin seized declined 64% coinciding with the Australian heroin shortage, from an average of 184 kg during 1998,2000 to 67 kg on average during 2001,03. Among 1587 VIDUS participants, the period coinciding with the Australian heroin shortage was associated independently with reduced daily injection of heroin [adjusted odds ratio: 0.55 (95% CI: 0.50,0.61); P < 0.001]. Conclusions Massive decreases in three independent markers of heroin use have been observed in western Canada coinciding with the Australian heroin shortage, despite no increases in funding to Canadian enforcement efforts. Markedly reduced Canadian seizure activity also coincided with the Australian heroin shortage. These findings suggest that external global heroin supply forces deserve greater investigation and credence as a potential explanation for the Australian heroin shortage. [source] | ||||||||||||||||||||||||||||||||||||||||||||||