Canadian Arctic Region Research Articles

Homeless Inuit in Montreal

Migration of the Inuit into southern Canadian cities from the Arctic increased substantially during the 1980s. Approximately 10,000 out of a total of 50,000 Inuit lived outside the Canadian Arctic regions in 2006. As the number of urban Inuit is increasing, so too is that of homeless Inuit in large southern cities. It is estimated that there are more than 90 homeless Inuit in Montreal, which has an Inuit population of about 800. This paper describes the life and characteristics of homeless urban Inuit in Montreal, and the activities of the Native Friendship Centre of Montreal and of the Association of Montreal Inuit, which are essential for their survival. The Inuit of Montreal have yet to form useful social networks to ease their urban adaptation. An Inuit community centre, where information and food can be shared, should be established in Montreal to change the present situation of homeless Inuit.

Gowardia (Parmeliaceae)—a new alectorioid lichen genus with two species

In recent years, Alectoria in the Acharian sense has been shown to contain several discordant elements, now recognized as separate genera, including Bryoria, Nodobryoria, Pseudephebe and Sulcaria. Here we describe a new segregate genus Gowardia. At present, Gowardia contains two species: G. arctica sp. nov. and G. nigricans (Ach.) comb. nov. (syn. Alectoria nigricans). In addition to several morphological and chemical characters, our decision to recognize Gowardia as distinct from Alectoria is supported by phylogenetic analysis based on combined ITS and GAPDH data. Gowardia arctica is known from Arctic regions of Canada and Russia, while G. nigricans has a wider range. Alectoria vancouverensis is documented from Finland, which is the first report of the species outside the Pacific coast of North America.

Multi‐year sea‐ice conditions in the western Canadian arctic archipelago region of the northwest passage: 1968–2006

Numerous studies have reported decreases in Arctic sea‐ice cover over the past several decades and General Circulation Model (GCM) simulations continue to predict future decreases. These decreases — particularly in thick perennial or multi‐year ice (MYI) — have led to considerable speculation about a more accessible Northwest Passage (NWP) as a transit route through the Canadian Arctic Archipelago (CAA). The Canadian Ice Service Digital Archive (CISDA) is used to investigate dynamic import/export and in situ growth of MYI within the western CAA regions of the NWP from 1968 to 2006. This analysis finds that MYI conditions in the western CAA regions of the NWP have remained relatively stable because the M'Clintock Channel and Franklin regions continuously operate as a drain‐trap mechanism for MYI. Results also show that in addition to the Queen Elizabeth Islands (QEI) region, the Western Parry Channel and the M'Clintock Channel are also regions where a considerable amount of MYI forms in situ and combined with dynamic imports contributes to heavy MYI conditions. There is also evidence to suggest that more frequent dynamic import of MYI appears to have occurred since‐1999 compared to the formation of more MYI in situ before 1999. As a result, the drain‐trap mechanism that has historically maintained heavy MYI conditions in the NWP is perhaps operating faster now than it was in the past. Based on the 38‐year MYI record examined in this study, it is likely that the mechanisms operating within the western CAA regions of the NWP can facilitate the continued presence of MYI for quite some time.

Multidecadal hydroclimatic variability in northeastern North America since 1550 AD

A network of varve and dendrochronological time series that provide annual resolution of Boreal tree growth conditions and Arctic snow pack and melt variability were used to investigate the imprint of the Atlantic Multidecadal Oscillation (AMO) on continental hydroclimatic variability in northeastern and northern North America from 1550 to 1986 AD. The hydroclimatic proxies show a coherent, AMO-like spectral pattern active since the late sixteenth and the early eighteenth century in the Canadian Arctic and southeastern Boreal regions, respectively. Positive AMO phases are associated with more intense spring runoff in the Arctic and with longer growth season and increased summer moisture availability in the southeastern boreal forest. These results offer new insights about the widespread response of North American hydroclimate to low frequency changes in North Atlantic sea surface temperatures.

Toxicological Effects of In Utero and Lactational Exposure of Rats to a Mixture of Environmental Contaminants Detected in Canadian Arctic Human Populations

As part of the program to investigate mixture effects of environmental pollutants, this study describes clinical, biochemical, and histopathological effects in rats perinatally exposed to a mixture of persistent organochlorine pollutants and methylmercury that simulates the blood contaminant profile of humans residing in the Canadian Arctic. Groups of pregnant rats were administered orally 0, 0.05, 0.5, or 5 mg/kg body weight (bw)/d of a reconstituted mixture of organochlorine pollutants (referred to as mixture hereafter) from gestational day (GD) 1 to postnatal day (PND) 23. Positive and vehicle controls were given Aroclor 1254 (Aroclor hereafter, 15 mg/kg bw) and corn oil (vehicle), respectively. After parturition, the pups were colled to 8 per litter on PND 4, and killed on PND 35, 77, or 350, when tissues were collected for analysis. Gestational and lactational exposure of rats to mixture up to 5 mg/kg bw produced adverse effects in the offspring, including growth suppression, decreased spleen and thymic weights, increased serum cholesterol and liver microsomal enzyme activities, lower liver retinoid levels, and histological changes in the liver, thyroid, and spleen. Histological changes in the liver consisted of hepatic inflammation, vacuolation, and hypertrophy, while alterations in the thyroid were characterized by hypertrophy and hyperplasia of follicles. The hepatic and thyroidal effects were mild even at the highest dose. The spleen showed a dose-dependent atrophy in the lymphoid nodules and periarteriolar lymphatic sheath regions. Aroclor produced effects similar to those seen in the highest mixture group. In summary, this study demonstrates that exposure to the reconstituted mixture at 5 mg/kg bw produced growth suppression, changes in organ weights, and biochemical and histopathological changes in liver, thyroid, and spleen. This study also demonstrated that the blood level in rats given the 5-mg/kg dose, where most of the effects were observed, is 100-fold higher than the blood level in the 0.05-mg/kg group, which is comparable to that found in humans living in the Canadian Arctic region.

Assessment of spring snow cover duration variability over northern Canada from satellite datasets

Variability in northern hemisphere (NH) spring and summer snow extent is strongly influenced by snow cover duration (SCD) across the Canadian Arctic. In order to assess the accuracy with which satellite-derived snow extent datasets capture the dynamic melt period (1 April–31 July), SCD datasets derived from the weekly NOAA snow chart record (1979–2004), daily IMS product (2000–2004), passive microwave (PMW) brightness temperatures (1979–2004), and Ku-band QuikSCAT scatterometer data (2000–2004) were assessed against in situ measurements across the Canadian Arctic (north of 60°). The higher resolution IMS and QSCAT datasets showed the best ability to capture spatial variability in spring SCD over the Canadian Arctic, followed by the NOAA and PMW datasets. The poorer performance of the PMW was anticipated because of documented difficulties monitoring snow cover over forested and mountainous terrain. Both the IMS and the NOAA datasets exhibited positive biases of ∼ 22–26 days which can be related to elevation effects and frequent cloud cover. The NOAA dataset was unable to capture interannual variability in spring snow cover over the central Canadian Arctic tundra region (66–74° N, 80–120° W) while the PMW was able to capture a significant fraction of the observed variability. This fact, combined with anomalous snow-cover temperature responses in the NOAA data further reinforces the conclusions of Wang et al. [Wang, L., Sharp, M., Brown, R., Derksen, C., & Rivard, B., (2005a). Evaluation of spring snow covered area depletion in the Canadian Arctic from NOAA snow charts. Remote Sensing of Environment, 95, 453–463] that considerable care be taken when using NOAA data during the summer months (June–August) where NH snow cover variability is controlled by relatively small regions with frequent cloud cover. QuikSCAT data were able to provide comparable results to IMS over the 2000–2004 period, indicating that Ku-band scatterometer measurements can make an important contribution to monitoring terrestrial snow extent during spring melt.

Landsat ETM+ mosaic of northern Canada

Mapping northern Canada with medium spatial resolution (30 m) Landsat data is important to complement national multiagency activities in forested and agricultural regions, and thus to achieve full Canadian coverage. Northern mapping presents unique challenges due to limited availability of field data for calibration or class labeling. Additional problems are caused by variability between individual Landsat scenes acquired under different atmospheric conditions and at different times. Therefore, the generation of radiometrically consistent coverage is highly desirable to reduce the amount of reference data required for land cover mapping and to increase mapping efficiency and consistency by stabilizing spectra of land cover classes among hundreds of Landsat scenes. The production chain and dataset of a normalized, 90 m resolution Landsat enhanced thematic mapper plus (ETM+) mosaic of northern Canada is presented in this research note. A robust regression technique called Thiel–Sen (TS) is used to normalize Landsat scenes to consistent coarse-resolution VEGETATION (VGT) imagery. The derived dataset is available for any interested user and can be employed in applications aimed at studying processes in the Canadian Arctic regions above the tree line.

Effective resource estimates for primary diamond deposits from the EKATI Diamond Mine™, Canada

Primary economic diamond deposit modelling has rarely been documented in the public domain. This paper presents information collected from significantly diamondiferous kimberlite pipes located near Lac de Gras in the Arctic region of Canada's Northwest Territories. The resource estimation process is widely accepted as a cyclical iteration of data collection and evaluation processes. A resource database is typically assembled from a large inventory of exploration data. These data must be methodically quality checked before accepting the information for interpretive analysis. The foundation of a mineral resource model is based on clear understanding of the geology model along with subsidiary grade, volume, and density models. Defining these models is an iterative process of statistical analyses and interpretation. As a deposit progresses along a path towards development, reducing risk to acceptable levels is critical for identifying and realizing its maximum value.

In vitro modulation of prolactin mRNA by toxaphene and 3,3′,4,4′-tetrachlorobiphenyl

It is now well recognized that many environmental contaminants are capable of disrupting endocrine processes in a variety of species, including birds, mammals, reptiles, and fish. Among these contaminants are toxaphene and polychlorinated biphenyls (PCBs), two of the most prevalent contaminants present in aquatic food chains of the Great Lakes and the Canadian Arctic region. We set out to investigate the possible endocrine-modulating activities of toxaphene, the PCB congener 3,3′,4,4′-tetrachlorobiphenyl (TeCB), an equimolar mixture of both compounds (toxaphene/TeCB), and estradiol (E2) (E2/toxaphene, E2/TeCB) on prolactin (PRL) mRNA expression. Concentrations ranging from 10−7 to 10−11M for both toxaphene and TeCB were assayed but only toxaphene modulated PRL mRNA levels, as determined by relative quantitative reverse transcriptase-polymerase chain reaction. Maximal induction by toxaphene was seen at 10−7M, resulting in a fourfold increase in PRL mRNA levels. No interactions were observed for combinations of the test substances. Our study demonstrates that toxaphene may exhibit estrogen-like activity by modulating PRL mRNA levels in GH3 cells.

Climate Variability and Climatic Change: Potential Implications for Hudson Bay Coastal Communities

Hudson Bay (HB) is one of the largest inland seas in the world, and is located within the subarctic and arctic regions of Canada. Regional climates in the HB bioregion are influenced by yearly cycles of ice-covered and ice-free seasons, tending to contribute to high interannual variability. Cree and Inuit communities established along the HB coasts have adapted and responded to these seasonal fluctuations for generations. Their experiences have facilitated the development and refinement of intimate relationships with marine/terrestrial wildlife and ecosystems. This paper reviews the past and current land use and resource harvesting practices of coastal communities. Having identified the importance of certain renewable resources to distinct subregions of HB, local and scientific observations of a changing environment are presented. This interdisciplinary overview of experienced and observed changes is used to facilitate a conceptual evaluation of the potential effects of climate variability and/or climatic change on HB coastal communities.

FRESHWATER DIATOMS FROM THE CANADIAN ARCTIC TREELINE AND DEVELOPMENT OF PALEOLIMNOLOGICAL INFERENCE MODELS1

Relationships between surface sediment diatom assemblages and measured environmental variables from 77 lakes in the central Canadian arctic treeline region were examined using multivariate statistical methods. Lakes were distributed across the arctic treeline from boreal forest to arctic tundra ecozones, along steep climatic and environmental gradients. Forward selection in canonical correspondence analysis determined that dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), total nitrogen (TN), lake surface area, silica, lake‐water depth, and iron explained significant portions of diatom species variation. Weighted‐averaging (WA) regression and calibration techniques were used to develop inference models for DIC, DOC, and TN from the estimated optima of the diatom taxa to these environmental variables. Simple WA models with classical deshrinking produced models with the strongest predictive abilities for all three variables based on the bootstrapped root mean squared errors of prediction (RMSEP). WA partial least squares showed little improvement over the simpler WA models as judged by the jackknifed RMSEP. These models suggest that it is possible to infer trends in DIC, DOC, and TN from fossil diatom assemblages from suitably chosen lakes in the central Canadian arctic treeline region.

Wintertime precipitation behavior in the western Canadian Arctic region

To investigate the precipitation formation process in the two major types of weather systems (“Pacific origin” and “storm track” types) in the western Canadian Arctic region, an X‐band vertical pointing Doppler radar, microwave radiometer were installed at Inuvik, Northwest Territories, Canada, during the midwinter of 1995/1996. Precise precipitation observations specially for ice crystals with replicator, microscope, and close‐up photos were also conducted at the same place. Precipitation formation mechanisms were quite different between these two major weather systems. For the Pacific‐origin‐type disturbance, warm and moist air was advected from the Pacific Ocean between 1.5 and 3.5 km msl. Convective echo patterns appeared by radar, and a large amount of precipitable water vapor and liquid water path were estimated by a microwave radiometer. As the air temperature was below the freezing point, the liquid water was identified as being in the supercooled state. Densely rimed dendrites and graupel particles were observed predominantly on the ground. Collision and coalescence processes of supercooled cloud droplets were dominant. On the contrary, for the storm track disturbance the moisture came from the Arctic Ocean, and strong winds were observed on the ground. The air mass was colder than −20°C throughout the layer. Stratiform echo patterns were observed by radar, a smaller amount of precipitable water vapor, and only a small liquid water path were observed by a microwave radiometer. It was suggested that the condensation growth was predominant. Snow crystal shapes of plates, columns, and bullet rosettes were observed predominantly on the ground.

Correlation of Cenozoic Sequences of the Canadian Arctic Region and Greenland; Implications for the Tectonic History of Northern North America

Correlation of Cenozoic Sequences of the Canadian Arctic Region and Greenland; Implications for the Tectonic History of Northern North America

In Memoriam: David F. Parmelee, 1924-1998

winian view of natural selection on individuals. Thirty-five years later, and after much research, the idea of group selection is still rejected by most ecologists and evolutionists. However, the book stimulated an enormous amount of research, notably on aspects of bird behavior, forming what is perhaps Wynne-Edwards' greatest contribution to the development of ecological and behavior science. His contribution to the development and management of science was marked by numerous awards and accolades. He was elected Fellow of the Royal Society of Edinburgh in 1950. He held a visiting professorship at Louisville in Kentucky in 1959, and visited New Zealand as a British Council Commonwealth Interchange Fellow in 1962. He was also a Leverhulme Fellow from 1978 to 1980 and was awarded honorary fellowships in the American Ornithologists' Union (1959), the Cooper Ornithological Society (1961), the Societas Scientiarum Fennica (1965), the British Ecological Society (1977), and the Institute of Biology (1980); Wynne-Edwards was President of the British Ornithologists' Union from 1965 to 1970. He was awarded honorary degrees from Stirling and Aberdeen Universities, the BOU Godman-Salvin Medal, the Neill Prize of the Royal Society of Edinburgh in 1977 for his outstanding contribution to natural history in Scotland, and the Frink Medal of the Zoological Society of London in 1980. He was awarded a D.Sc. degree at Oxford and elected Fellow of the Royal Society of London in 1970, eight years after the publication of his magnum opus. Wynne is survived by his wife, son, daughter, seven grandchildren, and seven great grandchildren. All of his descendants live in Canada, and most have strong connections with Queen's University. As a result of these connections, and the value of Wynne's early work in the Canadian arctic and Gaspe regions, his surviving papers and books went to Kingston, Ontario. They include 80 years of daily diaries and correspondence notes and manuscripts for Animal Dispersion, all housed together as a Special Collection in the library system. The passing of Vero Wynne-Edwards has marked the end of an era in the development of ecological science. To those close to him, he will be remembered for his self confidence, erudition and scholarship, and for his authority, delivered with a firm but usually gentle touch; a somewhat unusual man, but one who had a great influence on the development of behavioral ecology.

In vitro investigation of toxaphene genotoxicity in S. typhimurium and Chinese hamster V79 lung fibroblasts

The polychlorinated pesticide toxaphene has been identified as a persistent environmental contaminant and is of particular concern in the Great Lakes and Arctic regions of Canada. Inconsistencies in published in vitro genotoxicology studies have hindered risk assessments of toxaphene exposure. When toxaphene mutagenicity was re-evaluated in the Ames Salmonella/microsome assay at 10–10,000 μg/plate, a dose-dependent increase in His revertants occurred in all five strains of S. typhimurium tested (TA97, TA98, TA100, TA102 and TA104) with higher mutation frequencies observed in the absence of S9 metabolic activation. However, the mutagenic potential of toxaphene was relatively low with concentrations greater than 500 μg/plate required to induce mutation. Toxaphene genotoxicity was also examined in a mammalian system using Chinese hamster V79 lung fibroblasts with metabolic activation provided by human HepG2 hepatoma cells. Genotoxicity of 1–10 μg/ml toxaphene was examined by measuring the frequency of sister chromatid exchange (SCE) and mutation induction at the hypoxanthine guanine phosphoribosyl transferase ( HGPRT) gene locus. Although small increases in SCE were observed at toxic concentrations of toxaphene approaching the LD 50 (10 μg/ml), they were not found to be statistically significant relative to control. Toxaphene was also unable to induce HGPRT mutagenesis at the concentrations tested. These results show that while toxaphene is a weak, direct-acting mutagen in the Ames Salmonella Test, convincing evidence of dose-dependent SCE induction and mutagenicity at the HGPRT gene locus could not be demonstrated in V79 cells.

General and Specific Biomarkers in some Tertiary Fossil Woods from Canadian Arctic

Four fossil woods, between 55 and 65 million years old, coming from the Canadian Arctic regions were analysed with respect to their dichloromethane extract components. In comparison with the extracts of younger fossils they contained only a limited number of components which belonged, furthermore, to relatively few classes of compounds namely aliphatic hydrocarbons, fatty acids, long chain alcohols and diterpenes. The fossil identified as a Douglas fir had only one of the expected compounds owing, perhaps, to the rather low amount of extractives or terpenes in the original wood. Another fossil, might have been a spruce. while of the remaining two unidentified fossils one could be attributed to a terpene-rich species (e. g. larch) while the other to a species rich in extractives different from diterpenes. However, much more data, based on samples taken from various locations and with a different composition of extractives are needed in order to determine the influence of a specific environment on aging.

Analysis of organochlorine pesticides using solid-phase microextraction

A solid-phase microextraction (SPME) procedure has been developed to successfully extract eighteen chlorine-containing pesticides from water. A fused-silica fiber coated with a non-polar polydimethylsiloxane stationary phase was used to extract the analytes from water samples over a concentration range of 0.001 to 100 ng/ml. Limits of detection at a ng/l level were achieved with GC and flame ionization detection, and improved to sub ng/l levels using GC-MS, or GC with electron-capture detection (ECD). The reproducibility of the measurements between fibers was found to ber very good, with precision typically below 20% R.S.D. within a single fiber. Qualitative analysis was performed on river and lake samples from Southern Ontario. Samples from the Arctic region of Canada were analyzed quantitatively using a dual ECD system.

Western Arctic Women Artists: An Ethnographic Study of the Historic Influences on the Artistic Education and Production of Women from Three Co-existing Cultures

Western Arctic Women Artists: An Ethnographic Study of the Historic Influences on the Artistic Education and Production of Women from Three Co-existing Cultures

The Northern Aquatic Food Chain Contamination Database: a research tool

During a review of data on the contamination of Canadian Arctic regions, it became apparent that a system should be developed to manage the vast array of information available. This conclusion led to the development of the Northern Aquatic Food Chain Contamination Database. It contains information on all contaminants for which data were available in the regions comprising the Yukon and Northwest Territories, the Hudson and James Bay basins, northern Que´bec (Nunavik), and Labrador. Data on Greenland were also included. Data were gathered from an extensive literature review, as well as from organizations and researchers. More than 30 variables are attached to each mean concentration value, including location, species, reference, % water, % lipids, age, sex, contaminant identification, standard deviation, minimum and maximum, and sampling date. All variables are subject to availability from the authors. The area under study is divided into 10 distinct regions to facilitate data management. Sample locations are geographically referenced to permit the use of geographical information systems. The database is mounted on the 4th DIMENSION software and was developed to provide an adequate standard of user friendliness. Since the database was developed for both immediate and future needs, it has sufficient flexibility to be useful to any researchers dealing with contaminants in northern regions.

Cadmium concentrations in recent snow and firn layers in the Canadian Arctic.

It is becoming increasingly evident that long-range transported pollutants can have a devastating effect on the fragile ecosystems of the Canadian Arctic region. The phenomenon of Arctic haze which prevails during the late winter-early spring period results in the flux of elevated quantities of toxic pollutants to the region. Although there have been studies of the atmospheric concentrations of pollutants in the region, there are no reliable measurements of the accumulation of trace metals in the snow and ice layers. Analysis of dated snow and ice layers in Greenland has furnished a wealth of information on the history of global air pollution with toxic metals. Similar studies in Arctic Canada should provide additional insights into the hemispheric transport processes and the sources of trace metals in this polar region. This report presents the first set of data on the concentrations of cadmium in recent snow layers (deposited during the past 7 years) of the Agassiz Ice Cap, Ellesmere Island, Canada. The data were obtained using an ultra-clean sampling and analysis procedures.