West Coast Of Canada Research Articles

Beta2-adrenergic receptor allele frequencies in the Quechua, a high altitude native population.

The beta2-adrenergic receptor is involved in the control of numerous physiological processes and, as the primary catecholamine receptor in the lungs, is of particular importance in the regulation of pulmonary function. There are several polymorphic loci in the beta2-adrenergic receptor gene that have alleles that alter receptor function, including two (A/G46, G/C79) that increase agonist sensitivity. As such a phenotype may increase vaso and bronchial dilation, thereby facilitating air and blood flow through the lungs, we hypothesized that selection may have favoured these alleles in high altitude populations as part of an adaptive strategy to deal with the hypoxic conditions characteristic of such environments. We tested this hypothesis by determining the allele frequencies for these two polymorphisms, as well one additional missense mutation (C/T491) and two silent mutations (G/A252 and C/A523) in 63 Quechua speaking natives from communities located between 3200 and 4200 m on the Peruvian altiplano. These frequencies were compared with those of two lowland populations, one native American (Na-Dene from the west coast of Canada) and one Caucasian of Western European descent. The Quechua manifest many of the pulmonary characteristics of high altitude populations and differences in allele frequencies between the Quechua and lowlanders could be indicative of a selective advantage conferred by certain genotypes in high altitude environments. Allele frequencies varied between populations at some loci and patterns of linkage disequilibrium differed between the old-world and new-world samples; however, as these populations are not closely related, significant variation would be expected due to stochastic effects alone. Neither of the alleles associated with increased receptor sensitivity (A46, G79) was significantly over-represented in the Quechua compared with either lowland group. The Quechua were monomorphic for the C allele at base 79. This variant has been associated with body mass index; however no clearly defined metabolic phenotype has been established. In addition, we sequenced the coding region of the gene in three unrelated Quechua to determine if there were any other polymorphisms common in this population. None were detected.

Stand delineation and composition estimation using semi-automated individual tree crown analysis

Stand delineation and species composition estimation are cornerstones of forest inventory mapping and key elements to forest management decision making. Improved mapping techniques are constantly being sought in terms of speed, consistency, accuracy, level of detail, and overall effectiveness. Semi-automated analysis of high-resolution imagery at the individual tree crown level may offer such benefits. Methods, however, need to be developed and tested under a variety of forest conditions. High-resolution (60 cm) multispectral airborne imagery was acquired over a predominantly young conifer forest and plantation test area on the west coast of Canada. Automated tree isolation algorithms were applied to the data in order to delineate tree crowns or clusters of crowns. An object-oriented single tree classification was conducted using a maximum likelihood classifier. Stands of similar species composition, closure, and stem density were defined through a sequence that first generated images of these parameters from the automated delineation and classification, used these as input to an unsupervised classification, and then filtered and smoothed the resulting classification clusters. Because of the dense nature of the stands and small crowns on the site, the isolation process often delineated clusters of several trees. Species classification accuracy was determined by comparing the average stand composition from the automated technique to that derived from ground transects or plots. Species classification was good, with average composition error (difference between field measured and automated composition) over all 16 test stands being 7.25%. Most errors for individual species in stands were below 20%, but a few were up to 30%. The automatically generated stand boundaries mimicked well those of known plantation and interpreted inventory boundaries. The automated technique created a few larger stands and some additional small stands in areas of complex forest structure. Overall, for the young fairly uniform stands of the site, both stand delineation and species composition estimation were of a quality suitable for operational use in inventory and forest management. Further development and testing is needed to extend results to situations covering large areas, multiple flight lines, varied topography, and different forest conditions.

Dissertation Titles and Synopses

Dissertation Titles and Synopses

Temperature, Wind and Wave Climatologies, and Trends from Marine Meteorological Buoys in the Northeast Pacific

Time series of sea surface temperature, wind speed, and significant wave height from meteorological buoys off the west coast of Canada and the adjacent United States are long enough and of sufficient quality to be useful for studying interannual variability and trends. Long-term averages of data provide a precise climatology of surface temperature, wind speed, and wave height for locations along- and offshore. Data from many of the buoys suggest a warming trend, but only three buoys show statistical significance, and sheltered buoys show no increases. Both the wind speed and the wave height data show an increasing trend with more statistical significance. Future data from these buoys should benefit from better calibration and a wider variety of sensors, as well as from longer time series.

A bicriteria knapsack program for planning remediation of contaminated lightstation sites

The Coastguard manages over 40 lighthouse sites on the West Coast of Canada. All of these have some ground contamination from lighthouse activities or other earlier uses of the location, such as military fortification. Now the federal government is requiring its departments to identify all pollution on land that it owns or leases, and develop an environmental management plan for contaminated sites. The author has worked with the Canadian Coast Guard, Pacific Region (CCG-PR) to develop a set of environmental criteria for prioritizing management and remediation at the lighthouse sites. The next step is to apply these criteria to determine the best action to take once preliminary environmental assessments of the sites have been completed. Two criteria dominate the immediate next actions at a site. One is the Canadian Council of Ministers of the Environment (CCME) Score, which is a measure of estimated environmental risk, and would be reduced by some immediate remediation. The other is Uncertainty, which estimates the incompleteness of the preliminary assessment and would be reduced by further testing. Working with these two criteria and a limited budget, deciding the best next step can be formulated as a bicriterion 0–1 knapsack problem. A comprehensive solution of the problem would require a parametric analysis over all possible relative weights of the two criteria, and also a parametric analysis for the budget. An exact solution would require much computation, and such a solution process could not easily be handed over to CCG-PR personnel. However, if the integer requirement in the formulation is relaxed, the problem becomes simply a matter of ranking projects by their best benefit/cost ratio, and selecting projects down the list until all the budget is allocated. This is the solution approach used here, and which is being passed to CCG-PR headquarters for their continued use. The paper illustrates the method with some disguised data from the actual CCG-PR studies.

PCBs in dungeness crab reflect distinct source fingerprints among harbor/industrial sites in British Columbia.

Dungeness crab (Cancer magister) samples were collected from various pulp mill and principal harbor sites on the West Coast of Canada. Full congener PCB analysis was performed on several composite and single hepatopancreas samples from each site, and the spatial variability of PCB patterns was explored. A recently developed direct mixing model (DMM) which relies on iteration of representative Aroclor end-members was used to make source predictions based on congener-specific PCB data from biota. Additionally, factor analysis and principal component analysis (FA/PCA) were applied to examine the intersite variability for potential PCB-source patterns. This unsupervised exploratory analysis (i.e., FA/PCA) revealed three distinct clusters of variables containing either low (di-tetra), moderate (penta-hexa), and high (hepta-nona) levels of chlorination, which were related to common Aroclor mixtures (e.g., A1242, A1248, A1254, and A1260). Overall, the PCA scores for each site qualitatively agreed with the source predictions provided by the DMM, and distinct source compositions were predicted for various sites examined.

Evolution of the Dawson caribou (Rangifer tarandus dawsoni)

The Dawson caribou (Rangifer tarandus dawsoni) was a rare subspecies of caribou that inhabited Haida Gwaii, an archipelago located 80 km off the west coast of Canada. It became extinct during the early part of the 20th century and to this day all that remains of Dawson caribou are several pelts, skulls, and antlers. With the exception of a physical description based on these remains, not much is known about the taxonomy of this subspecies of caribou. Using molecular and ancient-DNA techniques, we sequenced 215 base pairs of the mitochondrial gene cytochrome b and compared these sequences with those from conspecifics Rangifer tarandus caribou (woodland caribou) and Rangifer tarandus granti (barren-ground caribou). These analyses suggest that the Dawson caribou was not genetically distinct. The unique morphology characterizing this extinct form of caribou may have been of recent origin, either from local selection pressures or from environmentally induced phenotypic plasticity.

Implications of a late-glacial pollen record for the glacial and climatic history of the Fraser Lowland, British Columbia

Late-glacial sediments at Mike Lake in the Fraser Lowland of southwestern British Columbia shed light on the timing and significance of the Younger Dryas and Sumas events on the west coast of Canada. Five pollen zones span the period from about 11 700 to 9700 radiocarbon years before present (yr BP) or 13 700 to 11 200 calibrated calendar years before present (cal BP). Climate during this interval is inferred to have ranged from cool continental to warm and dry. Changes in pollen assemblages, lithology, and loss on ignition in Mike Lake sediments deposited prior to 11 000 yr BP (13 000 cal BP) may signal the Sumas glacial advance, which has been dated elsewhere in the Fraser Lowland to this time. Palynologic and sedimentological data indicate that there was much climatic and ecological variability in southwestern British Columbia during the Younger Dryas chronozone. Detrended correspondence analysis of modern pollen from lake-sediment surface samples collected throughout British Columbia is used to compare Mike Lake fossil pollen assemblages to modern vegetation zones. The inferred vegetation assemblage during most of the Younger Dryas chronozone indicates a progressively warming climate with a cool interval between 10 400 and 10 000 yr BP. The pollen assemblage in this interval is similar to that of present subalpine forests on the west coast of Canada. The cooling coincides with the later part of the Younger Dryas chronozone and occurred too late to be the driving mechanism for the final Sumas advance, which peaked around 11 300 14C yr BP (13 200 cal BP).

An analysis of intermodal transport carrier selection criteria for pacific-rim imports to New England

The introduction of double stack rail services opened up a variety of transportation options for shippers located in the North Eastern parts of the U.S. The availability of transcontinental double stack service from the Canadian West Coast has increased this option even further particularly because of a recent new service introduced by a small U.S. railroad company. The paper uses Analytical Hierarchy Process (AHP) methodology to provide a decision-making framework for the intermodal choices of shippers located in the region suitable for duplication elsewhere where similar options exist.

Moving Pictures and Costume Songs at the 1927 “Exhibition of Canadian West Coast Art, Native and Modern”

En 1927, Nass River Indians et Totem Land furent produits spécifiquement pour être présentés à l'intérieur d'une exposition au Musée des beaux arts du Canada qui réunissait des oeuvres autochtones de la côte ouest et des tableaux et sculptures d’artistes euro-canadiens importants. Il ne s’agit là que de l’un des nombreux contextes dans lesquels ces films anthropologiques ont circulé. Il est donc important de ne pas examiner ces textes isolément dans le cadre d’une histoire du film ethnographique canadien. On se doit plutôt de les situer dans le cadre beaucoup plus large d’une « histoire de l’art » de cette culture matérielle que Fatima Tobing Rony a appelé « l’ethnographique », c’est-à-dire, ces peuples que le cinéma ethnographique présenta comme « n’ayant aucune histoire, aucune écriture, aucune civilisation, aucune technologie et aucune archive ».

Deep Water Renewal in the Strait of Georgia

The Strait of Georgia is a semi-enclosed basin on the Canadian west coast in which exchange with the shelf is restricted by narrow constrictions and shallow sills. The local dynamics are mostly dominated by the mixed tides and by the estuarine circulation that is forced mainly by discharge of fresh water from the Fraser River. The intermediate and deep water of the Strait are renewed through discrete deep water renewal events during which dense water flows over the sills and into the interior basin. Several data sets are closely examined to better understand the nature and variability of the deep water renewal process over a wide range of time scales. Measured deep water renewal (DWR) events are clearly identified, as well as their effects on the water properties in the deep basin. It is found that the events can be classified into two categories: late winter intrusions bring cold, oxygen rich water, and late summer events bring warm, saline, low oxygen water. These two DWR seasons determine the annual cycle of the deep water properties in the Strait of Georgia.For both seasons, the DWR events always occur following a neap tide, at which time the density of bottom water in the sill area peaks. However, not all neap tides are followed by a DWR event. During the DWR seasons, discrete events are found to occur every second neap tide. It is believed that this monthly periodicity is required to allow enough time for the salinity (density) of the deep water near the sill to increase sufficiently following the flushing of dense local water by the previous DWR event. Also, the timing of the two DWR seasons is explained in terms of the yearly cycle of the surface and bottom water density in the estuary: DWR events are more likely to happen at the beginning (spring) and end (fall) of the coastal upwelling season, when the Fraser River discharge is not too large. Finally, it is shown that, during El Niño years, unfavorable conditions develop that can shut down the late winter DWR season, leading to much warmer deep water during the following winter.

First record of blooms of Cochlodinium sp. (Gymnodiniales, Dinophyceae) causing mortality to aquacultured salmon on the west coast of Canada

Blooms of Cochlodinium sp., monitored for the first time on the west coast of Vancouver Island from August to October 1999, caused substantial mortality to farmed salmon, accounting for economic losses of about CAN $2 million. Cells of the alga were 25–40 μm long, 20–30 μm wide and had a torsion of 1.8 to 2 turns. Pairs of cells were common, forming up to 25% of the biomass; apart from the absence of longer chains, the morphology of the species, including the anteriorly placed nucleus and numerous golden chloroplasts, matched the gross morphological description of Cochlodinium polykrikoides. A strong diurnal pattern was observed in blooms at farm sites, with high cell concentrations overnight at depths of up to 25 m and dense surface blooms during the day. Surface concentrations of up to 60,000 cells ml−1 peaked in early September. Fish stopped feeding when cell counts exceeded 500 cells ml−1 in the net-pens, and mortality was observed above 2000 cells ml−1. Bioassays in the field with Atlantic salmon (Salmo salar) smolts demonstrated lethality after 120 min exposure and over 90% mortality after 500 min, when cell concentrations varied from 10,800 to 2700 cells ml−1 as the bloom moved through the test site. Under controlled laboratory conditions, S. salar smolts died within 27 min of exposure to 7200 cells ml−1 and 55 min with 3400 cells ml−1; although fish appeared distressed at 1000 cells ml−1, only 20% died within the 24 h bioassay. Enhanced toxicity of Cochlodinium sp., observed when the dinoflagellate was oxygenated or aerated, may have been a function of agitation, leading to increased release of lethal reactive oxygen species. Mitigation protocols of net-pen enclosures, with 14 m deep tarps and upwelling of deep water by aeration, proved less effective against Cochlodinium sp. than for Heterosigma akashiwo, the major harmful algal bloom killer of farmed salmon on the west coast of Canada.

Past and Present Acts of Exclusion

Past and Present Acts of Exclusion

Quit blubbering: an examination of Nuu'chah'nulth (Nootkan) whale butchery

AbstractArchaeological research on North America's northwest coast has produced evidence of aboriginal whale use spanning the past 4000 years. The Toquaht Archaeological Project, on the west coast of Canada's Vancouver Island, recovered numerous whale skeletal elements, many of which show butchering marks. This paper examines these elements from the points of view of element frequency, and of type and location of butchering marks. The examination of these marks reveals the portions into which the whales were cut, the sequence of butchering events, the kinds of tools used, and the frequency with which these elements were transported onto the site. These observations are compared with other archaeological data, especially from the Ozette site in neighbouring Washington state, and with ethnographic records. The importance of a variety of whale products, not just blubber and the oil rendered from it, is emphasized. Copyright © 2001 John Wiley & Sons, Ltd.

Fishing down Canadian aquatic food webs

The mean trophic level (TL) of fish landed in fisheries on the east and west coasts of Canada is declining by 0.03–0.10·decade–1, similar to global trends. This finding is based on data from United Nations Food and Agriculture Organization and the Canadian Department of Fisheries and Oceans and other Canadian sources for the period 1873–1997. Significant rates of decline in mean TL were obtained even when key species — Atlantic cod (Gadus morhua) on the east coast and Pacific herring (Clupea pallasi) and Pacific hake (Merluccius productus) on the west coast — were omitted from the analysis. Fish taken in inland water fisheries did not exhibit a decline in mean TL. Two models were developed, based on length and age, respectively, for correcting TL estimates of individual species for the effects of changes in body size due to changes in fishing mortality. Both produced corrections that were small relative to changes in mean TL that resulted from changes in species composition of the catch over time. Overall, these results suggest that the mean TL of fish landed can be used as an index of sustainability in multispecies fisheries and that its reliability will depend on the quality of the data and length of the time series available for analysis.

Spatial and temporal distribution of airborne Bacillus thuringiensis var. kurstaki during an aerial spray program for gypsy moth eradication.

We measured airborne exposures to the biological insecticide Bacillus thuringiensis var. kurstaki (Btk) during an aerial spray program to eradicate gypsy moths on the west coast of Canada. We aimed to determine whether staying indoors during spraying reduced exposures, to determine the rate of temporal decay of airborne concentrations, and to determine whether drift occurred outside the spray zone. During spraying, the average culturable airborne Btk concentration measured outdoors within the spray zone was 739 colony-forming units (CFU)/m3 of air. Outdoor air concentrations decreased over time, quickly in an initial phase with a half time of 3.3 hr, and then more slowly over the following 9 days, with an overall half-time of about 2.4 days. Inside residences during spraying, average concentrations were initially 2-5 times lower than outdoors, but at 5-6 hr after spraying began, indoor concentrations exceeded those outdoors, with an average of 244 CFU/m3 vs. 77 CFU/m3 outdoors, suggesting that the initial benefits of remaining indoors during spraying may not persist as outside air moves indoors with normal daily activities. There was drift of culturable Btk throughout a 125- to 1,000-meter band outside the spray zone where measurements were made, a consequence of the fine aerosol sizes that remained airborne (count median diameters of 4.3 to 7.2 microm). Btk concentrations outside the spray zone were related to wind speed and direction, but not to distance from the spray zone.

Balancing Act: Environmental Issues in Forestry (2nd ed.)

Review: Balancing Act: Environmental Issues in Forestry (2nd ed.) By J. P. Kimmins Reviewed by Joseph J. Nocera Nova Scotia Department of Natural Resources, Canada Kimmins, J. P. Balancing Act: Environmental Issues in Forestry. (2nd ed.) Vancouver, Canada: UBC Press, 1997. 305 pp. ISBN 0-7748-0574-9 (softcover). Finding a balance in a debate of extremes is a daunting task. In Balancing Act, the author attempts to describe all points between aggressive environmental protectionism and outright resource exploitation. Throughout the book, the reader is presented with numerous facts, theories, and research concerning the effects of exploitation and the fallacy of eternal hands-off protectionism. His facts are precise, and his presentation of all aspects of forestry is thorough—from climate change to groundwater issues. J. P. ( Hamish ) Kimmins offers a complete and extensive primer on forestry, forest science, and relevant topics. This background consists of five full chapters (73 pp.) and provides, as the author states, the average concerned citizen or forester with an introduction to the ecological aspects of the major environmental issues facing the managers of Canada’s great forest resource (p. 4). Even those readers armed with intricate knowledge of these disciplines will take home something new, or at least be reminded of something they may have forgotten. This lengthy introduction is well written and is the greatest strength of this book. Has the author managed to find a balance, as the title suggests? Throughout, Kimmins disclaims this work as not being a vehicle meant to resolve a debate. I suggest that he has accomplished neither the intended, or unintended, objectives. The entire work is one of a pro-forestry nature, albeit against blatant exploitation, where forests are considered a resource (e.g. see quote above). The objectivity that the author desires is lost in his repeated advocating of active forestry over forest protection. This is most evident in the very limited discussion on some sensitive wildlife issues. Wildlife that are dependent upon old-growth (requiring the least intensive style of forest management), seemingly receive a brush-off, with only one paragraph devoted to their discussion (p. 150). The reader is told how harvested forests beget different suites of species, but that overall diversity is unharmed. What about the inherent value of wildlife that resided there? Many of the issues raised and information presented are generated from the west coast of Canada, particularly the author’s home province of British

Out of the Woods: Tsimshian Women and Forestry Work

T story of work on the west coast of Canada has traditionally been one of rugged (white) men in fish-boats, mines and forests. The experiences of Aboriginal peoples as laborers and producers in resource industries have rarely been the focus of mainstream historical accounts (Knight 1996: 5). While such gaps in historical and ethographic records are being tackled by contemporary scholars, many of the less conspicuous stories of resource work in British Columbia remain untold. Recent research has tended to focus on Native men's experiences as fishers (Menzies 1992, Stevens 1992) and on Native women's wage labor in salmon canneries (Newell 1993, Muszynski 1992). Aboriginal women's long and complex history of involvement with the forest industry in British Columbia remains largely unexplored. In this article we will discuss some of the key social and economic processes at work during the colonization and industrialization of western Canada that have affected Aboriginal women's involvement in the forestry industry. The experiences of women of the Tsimshian Nation on the north coast of British Columbia offer a case study that spans over a century and a half of involvement in forestry work. In this case study we describe an alternative, gendered history of forestry and also highlight the forces working to dispossess Aboriginal peoples and, specifically, to disadvantage Aboriginal women. Tsimshian women's early involvement as laborers and producers, and their subsequent exclusion from both wage work and independent harvesting, illuminates the way that colonialism and capitalism have cooperated in the economic marginalization of Aboriginal women. Drawing from archival sources and life history interviews, Tsimshian women's involvement with commercial forestry is traced from the establishment of a Hudson Bay trading post in Tsimshian territory in 1834 until the present time. The exclusion of women from forestry, coincident with the shift from an Aboriginal economy to industrial resource extraction, will be related to the social and economic changes encouraged by church and state and dictated by the needs of capital. The shifting position of Aboriginal women in the resource

The effect of speckle filtering on scale-dependent texture estimation of a forested scene

Spatial fluctuations in microwave backscatter may be an important piece of information in discriminating tree stands. However, the presence of speckle in synthetic aperture radar (SAR) image data is a barrier to the exploitation of image texture. The authors explored a new methodology that combines a recent adaptive speckle reduction algorithm by Lopes et al. (1990) with a generic texture estimation scheme. They investigated the claim that this filter was capable of preserving backscatter texture. To understand if speckle reduction was destroying backscatter texture, they compared the strength of the relationship between forest inventory parameters and image texture as a function of spatial scale for both filtered and unfiltered images. They used Radarsat Fine mode image data: single look resolution is approximately 8.5 m, and pixel spacing is 3 m. Their study area was northern Vancouver Island, B.C., on the west coast of Canada. For the unfiltered data, they found that the ability of image texture to predict the forest parameters decreased as the texture scale increased from 3 to 13 m, suggesting greater information content in the small scale texture. For the filtered data, this relationship was much weaker at small scales and was not a function of distance. Their results suggest that the speckle filter was not retaining small scale texture, which is consistent with the theoretical hypotheses underlying its multiplicative noise model. They also show that there is significant information in small state SAR image texture that may be used as an adjunct to other spatial information for discriminating tree stands in the temperate rain forest.

What Determines Seasonal and Interannual Variability of Phytoplankton and Zooplankton in Strongly Estuarine Systems?

A coupled biological–physical box model is developed to investigate the seasonal and interannual variability of marine plankton in strongly estuarine systems such as the semi-enclosed estuary of the Strait of Georgia and Juan de Fuca Strait on the west coast of Canada. The estuarine circulation not only supplies nutrients to the euphotic layer but also transports plankton between the straits, causing an asymmetrical distribution of plankton biomass in the estuary. A specific set of biological parameters can be chosen so that the model predicts a large spring bloom and nutrient limitation in the Strait of Georgia but high nutrient levels and no spring bloom in the Juan de Fuca Strait, in agreement with observations. However, as the plankton growth and mortality rate parameters are varied over a realistic range, the plankton also exhibit two other ecosystem behaviours: one with a large spring bloom in the Juan de Fuca Strait and one with a low zooplankton stock in the Strait of Georgia.To determine possible causes for observed interannual variability of the planktonic ecosystem, we have run the coupled biophysical model with stochastic variation of the Fraser River runoff and the shelf salinity. The plankton populations are found to be insensitive to the interannual variability in the estuarine circulation. It is suggested that marine phytoplankton and zooplankton might respond more significantly to climate variability (or change) through changes in their biological rate parameters.