Articles de revues : « North Shore of the St. Lawrence »

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Ouellet, Jean-François, Pierre Fradette et Isabel Blouin. « Do Barrow's Goldeneyes, Bucephala islandica, Breed South of the St. Lawrence Estuary in the Gaspé Peninsula, Eastern Canada ? » Canadian Field-Naturalist 124, n^o 2 (1 avril 2010) : 179. http://dx.doi.org/10.22621/cfn.v124i2.1057.

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We report the first observations of Barrow's Goldeneyes south of the St. Lawrence estuary in typical breeding habitat during the breeding season. Until recently, the confirmed breeding locations for the species in Eastern North America were all located on the north shore of the Estuary and Gulf of St. Lawrence.

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Rail, Jean-François, et Gilles Chapdelaine. « Food of Double-crested Cormorants,Phalacrocorax auritus, in the Gulf and Estuary of the St. Lawrence River, Quebec, Canada ». Canadian Journal of Zoology 76, n^o 4 (1 avril 1998) : 635–43. http://dx.doi.org/10.1139/z97-237.

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Between 1994 and 1996, a total of 613 Double-crested Cormorant (Phalacrocorax auritus) regurgitations were collected at four colonies located in the St. Lawrence Estuary and one colony on the North Shore of the Gulf of St. Lawrence. The diet comprised a great variety of prey, with fishes well represented. Capelin (Mallotus villosus) and sand lance (Ammodytes sp.) together constituted most of the diet, (i.e., frequency of occurrence 66%, numerical frequency 68%, and volume 50%). Sand lance, which were nearly absent in regurgitations from the Estuary, were important in the diet of cormorants from the North Shore of the Gulf. At the North Shore colony, capelin were much more abundant in the diet in 1996 than in 1995, which correlates with independent fisheries data. In contrast to the results of previous studies of this cormorant's diet, our results show a preponderance of schooling fishes over benthic species. We suggest that this reflects a recent trend towards an increase in the abundance of schooling fishes in the St. Lawrence Estuary and Gulf. Overfishing of predatory fishes and oceanographic factors could be involved.

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Mingelbier, M., F. Lecomte et J. J. Dodson. « Climate change and abundance cycles of two sympatric populations of smelt (Osmerus mordax) in the middle estuary of the St. Lawrence River, Canada ». Canadian Journal of Fisheries and Aquatic Sciences 58, n^o 10 (1 octobre 2001) : 2048–58. http://dx.doi.org/10.1139/f01-140.

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Commercial catches of two ecologically distinct sympatric smelt (Osmerus mordax) populations segregated along the two shores of the St. Lawrence middle estuary exhibited inverse patterns with periodicities on the order of 30 years. The influence of water level in the St. Lawrence River and air temperature, chosen to reflect variations in hydrology and climate, differed markedly between the two populations. Analyses revealed that both water level and temperature were generally positively related with north-shore smelt landings and negatively related with south-shore smelt landings. For both populations, a number of significant climatic factors contributing to variance in smelt landings were lagged by one to three years relative to the year of landings, indicating that climatic variables influenced smelt recruitment. The contrasting role of hydroclimatic variables in driving these abundance cycles is likely related to differential exploitation of estuarine habitats; the south-shore population is associated with shallow shoal habitat, whereas the north-shore population is associated with deep channel habitat. The responses of the two smelt populations also reflect the fundamental ecological differences existing between shoal and channel habitats, indicating that future climate change may differentially affect other populations or species that are segregated between these two habitats.

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Pouliot, Daniel, et Jean-François Desroches. « Découverte de la Salamandre à quatre orteils, Hemidactylium scutatum, à Québec, Québec : limite nord-est de l'espèce sur la rive nord du fleuve Saint-Laurent ». Canadian Field-Naturalist 119, n^o 1 (1 janvier 2005) : 129. http://dx.doi.org/10.22621/cfn.v119i1.91.

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En 1999 trois spécimens de Salamandre à quatre orteils ont été observés à Québec, sur la rive nord du fleuve Saint-Laurent. Des recherches effectuées au même site en 2001 ont permis de découvrir d’autres spécimens de même que des pontes. Ces mentions élargissent la distribution connue de l’espèce de 90 km vers le nord-est-est et 80 km vers le nord-nord-ouest. Il s’agit vraisemblablement de la limite nord-est de cette salamandre, sur la rive nord du Saint-Laurent.In 1999, three Four-toed Salamanders were observed at Québec, north shore of the St. Lawrence River. Field searches in 2001 allowed the discovery of another specimen as well as egg clutches. These records extend the known range of the species 90 km north-east-east and 80 km north-north-west. This is probably the northeastern limit of this salamander’s range on the north shore of St. Lawrence River.

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Dionne, Jean-Claude. « Les erratiques de dolomie à Rivière-Blanche, côte sud de l'estuaire maritime du Saint-Laurent : un indicateur de transport glaciaire et glaciel ». Canadian Journal of Earth Sciences 39, n^o 8 (1 août 2002) : 1239–55. http://dx.doi.org/10.1139/e02-009.

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At Rivière-Blanche, a locality on the south shore of the lower St. Lawrence estuary, the clayey and rocky shore zone is largely covered by stones of various sizes and lithologies, from local and far-distant sources. A survey exceeding 31 000 boulders indicates that 31% are Precambrian clasts (granite, gneiss, anorthosite, etc.) from the Canadian Shield located on the north shore of the St. Lawrence, 40 km from Rivière-Blanche, and 69% are Appalachian lithologies, mainly (45%) sandstone and graywacke. There are also 1.5% of dolostone erratics, a lithology not widespread in the Canadian Shield nor in the Appalachians. Of the 1242 clasts of the various varieties of dolostone erratics observed, the grey coral (Cladopora) dolostone erratics are restricted to the Rivière-Blanche area, whereas many other varieties are common to both shores of the St. Lawrence estuary. The most likely far-distance source is the Proterozoic Mistassini sedimentary basin, while a few varieties such as the coral dolostone erratics are from the Appalachian Siluro-Devonian formations, of which the nearest outcrops are located in the northwestern area of Lake Matapedia, 2530 km south of Rivière-Blanche. Whatever their source, the dolostone erratics were first transported by a late Wisconsinian regional ice stream before being released by icebergs in the Goldthwait Sea. The coral dolostone (Clapodora) erratics provide additional evidence for a northward ice flow between Lake Matapedia and Rivière-Blanche during an early phase of deglaciation of the St. Lawrence Valley after the formation of an Appalachian ice divide located approximately at the latitude of Lac-au-Saumon.

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Pinet, Nicolas. « Southern continuation of the Wakeham Group and Robe-Noire mafic suite (eastern Grenville Province) from hydrocarbon-targeted seismic reflection data on Anticosti Island, Quebec, Canada ». Canadian Journal of Earth Sciences 53, n^o 9 (septembre 2016) : 875–82. http://dx.doi.org/10.1139/cjes-2016-0011.

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Hydrocarbon-targeted seismic reflection profiles acquired on eastern Anticosti Island (Quebec) image subparallel reflections with significant continuity below the Paleozoic St. Lawrence Platform. These intra-basement reflections define a seismic unit with a relatively simple geometry characterized by broad open folds, an array of subparallel markers, and east-northeast-dipping faults. The reflective seismic unit likely corresponds to the southern extension of the Mesoproterozoic Wakeham Group and Robe-Noire mafic sills that are exposed on the nearby north shore of the Gulf of St. Lawrence, in the eastern Grenville Province of Quebec.

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Lefèvre, Marylise A., Michael J. W. Stokesbury, Frederick G. Whoriskey et Michael J. Dadswell. « Atlantic salmon post-smolt migration routes in the Gulf of St. Lawrence ». ICES Journal of Marine Science 69, n^o 6 (1 juillet 2012) : 981–90. http://dx.doi.org/10.1093/icesjms/fss092.

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Abstract Lefèvre, M. A., Stokesbury, M. J. W., Whoriskey, F. G., and Dadswell, M. J. 2012. Atlantic salmon post-smolt migration routes in the Gulf of St. Lawrence – ICES Journal of Marine Science, 69: 981–990. The migration of Atlantic salmon (Salmo salar) post-smolts from the Rivière Saint-Jean on the north shore of the Gulf of St. Lawrence (Canada) was studied during 2009 and 2010. Salmon from rivers in this region spend ≥2 years at sea before returning to spawn, and are believed to migrate to ocean feeding areas off Greenland. To determine residency time in the nearshore environment, and to define the migration routes of post-smolts, tagged post-smolts were tracked passively in Jacques Cartier Strait and at the two exits of the Gulf of St. Lawrence to the Atlantic Ocean (Cabot Strait and the Strait of Belle Isle). Post-smolts moved rapidly south in the nearshore area; two of them were detected 45 km south of the estuary exit, suggesting that they were moving towards the centre of the Gulf of St. Lawrence. One tagged post-smolt was detected exiting the Gulf of St. Lawrence via the Strait of Belle Isle after 44 d and exhibited a minimum swimming speed of 14.4 km d−1. There was no apparent linkage between the detection patterns of post-smolts and surface water temperatures or surface water currents close to shore. Post-smolts, however, appeared to orient to higher salinity.

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Robert, Michel, Réjean Benoit et Jean-Pierre L. Savard. « Relationship Among Breeding, Molting, and Wintering Areas of Male Barrow's Goldeneyes (Bucephala Islandica) in Eastern North America ». Auk 119, n^o 3 (1 juillet 2002) : 676–84. http://dx.doi.org/10.1093/auk/119.3.676.

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Abstract Little is known of the eastern North American population of Barrow's Goldeneyes (Bucephala islandica), which was recently listed as “of special concern” in Canada. In 1998 and 1999, we marked 18 adult males wintering along the St. Lawrence River, Québec, with satellite transmitters to document their breeding, molting, and wintering distribution and phenology, and to describe timing and routes of their spring, molt, and fall migrations. Thirteen males moved inland from the St. Lawrence River to breed; the spring migration averaged 5.9 days, and birds arrived on breeding areas on average 9 May. All breeding areas were inland, on the north shore of the St. Lawrence River estuary and gulf. Breeding areas averaged 64.8 km from the St. Lawrence corridor. Males stayed on their respective breeding area a mean of 34.5 days, and left on average 11 June. Twelve males were tracked to their molting areas, one of which stayed on its wintering area until 5 June and flew directly to its molting area. Their molt migration averaged 18.6 days, and the mean arrival date on molting areas was 30 June. All molting areas were located north and averaged 986 km from breeding areas. Four males molted in Hudson Bay, four in Ungava Bay, two in northern Labrador, one on Baffin Island, and one inland, near the Québec–Labrador border. The mean length of stay on the molting areas was 105.3 days, and the mean date of departure from molting areas was 4 October. All goldeneyes for which the radio still functioned during fall migration returned to winter in the St. Lawrence River estuary, on average 6 November. Our results refute the idea that the main breeding area of the eastern North American population of Barrow's Goldeneyes is located in northern Québec and Labrador and rather indicate that it is in the boreal forest just north of the St. Lawrence River estuary and gulf. They also indicate that Barrow's Goldeneye males undertake a genuine molt migration, and highlight the importance of molting areas because birds stayed there approximately four months each year.

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Rail, Jean-François. « Eighteenth census of seabirds breeding in the sanctuaries of the North Shore of the Gulf of St. Lawrence, 2015 ». Canadian Field-Naturalist 135, n^o 3 (21 janvier 2022) : 221–33. http://dx.doi.org/10.22621/cfn.v135i3.2675.

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In 1925, ten migratory bird sanctuaries were created on the North Shore of the Gulf of St. Lawrence, and their breeding seabird populations have been censused every five years since. Between 2010 and 2015, only three alcid species exhibited positive population trends (Razorbill [Alca torda], Common Murre [Uria aalge], and Atlantic Puffin [Fratercula arctica]), while the remaining 13 species showed declining trends. Leach’s Storm-Petrel (Hydrobates leucorhous) and Caspian Tern (Hydroprogne caspia) are on the verge of disappearing from the sanctuaries, and the prolonged and rapid decline in Black-legged Kittiwake (Rissa tridactyla) is worrisome. Based on historical records since 1925, it appears that seabird communities are faring well in some sanctuaries (e.g., Baie de Brador, Îles aux Perroquets, and Îles Sainte-Marie), while numbers are at low levels in others (e.g., Île à la Brume, Baie des Loups, and Saint-Augustin). Human disturbance, harvest of seabirds (eggs and birds), and predation are among the issues potentially most affecting seabird populations on the North Shore of the Gulf of St. Lawrence.

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Allan, R. J. « The Saguenay Fjord : A Third Factor in the Toxic Chemical Contamination of the St. Lawrence River Estuary ». Water Quality Research Journal 25, n^o 1 (1 février 1990) : 1–14. http://dx.doi.org/10.2166/wqrj.1990.001.

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Abstract The Saguenay Fjord enters the north shore of the St. Lawrence River estuary. The St. Lawrence River is one source of a variety of toxic metals and organic chemicals to its estuary. Some of these chemicals are transported by the river from its source in Lake Ontario and others are added along its course. However, the second major source of water inflow to the St. Lawrence Estuary is the Saguenay Fjord, which is by no means free of contamination. This paper overviews the types of toxic metals and organic chemical contamination and sources in the fjord proper and upstream in its drainage basin. The principal contaminants recorded in bottom sediments are polyaromatic hydrocarbons and mercury. An extensive forest products industry may also be a source of toxic chlorinated organic chemicals. The combined (peak) inputs of these chemicals to the Saguenay Fjord system was in the past and may have continued for many years, even decades. The relationship between the type of contaminants introduced in the past to the St. Lawrence estuary by the St. Lawrence River and the Saguenay Fjord may have implications concerning contamination of the beluga whale population which is located most frequently in the estuary near the fjord inflow.

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Rutherford, Krysten, et Katja Fennel. « Diagnosing transit times on the northwestern North Atlantic continental shelf ». Ocean Science 14, n^o 5 (12 octobre 2018) : 1207–21. http://dx.doi.org/10.5194/os-14-1207-2018.

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Abstract. The circulation in the northwestern North Atlantic Ocean is highly complex, characterized by the confluence of two major western boundary current systems and several shelf currents. Here we present the first comprehensive analysis of transport paths and timescales for the northwestern North Atlantic shelf, which is useful for estimating ventilation rates, describing circulation and mixing, characterizing the composition of water masses with respect to different source regions, and elucidating rates and patterns of biogeochemical processing, species dispersal, and genetic connectivity. Our analysis uses dye and age tracers within a high-resolution circulation model of the region, divided into nine subregions, to diagnose retention times, transport pathways, and transit times. Retention times are shortest on the Scotian Shelf (∼ 3 months), where the inshore and shelf-break branches of the coastal current system result in high along-shelf transport to the southwest, and on the Grand Banks (∼ 3 months). Larger retention times are simulated in the Gulf of St. Lawrence (∼ 12 months) and the Gulf of Maine (∼ 6 months). Source water analysis shows that Scotian Shelf water is primarily comprised of waters from the Grand Banks and Gulf of St. Lawrence, with varying composition across the shelf. Contributions from the Gulf of St. Lawrence are larger at near-shore locations, whereas locations near the shelf break have larger contributions from the Grand Banks and slope waters. Waters from the deep slope have little connectivity with the shelf, because the shelf-break current inhibits transport across the shelf break. Grand Banks and Gulf of St. Lawrence waters are therefore dominant controls on biogeochemical properties, and on setting and sustaining planktonic communities on the Scotian Shelf.

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Pratte, Steve, Michelle Garneau et François De Vleeschouwer. « Late-Holocene atmospheric dust deposition in eastern Canada (St. Lawrence North Shore) ». Holocene 27, n^o 1 (28 juillet 2016) : 12–25. http://dx.doi.org/10.1177/0959683616646185.

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Dust deposition in two ombrotrophic peatlands (Baie and Ile du Havre peatland (IDH) bogs) of the Estuary and Gulf of the St. Lawrence in eastern Canada was reconstructed using elemental geochemistry. The rare earth elements (REEs) and other lithogenic element concentrations were measured by ICP-oES and Q-ICP-MS along two peat cores spanning the last 4000 years. Principal component analyses on the geochemical profiles show that REEs display the same behavior as Al, Ti, Sc, and Zr, all conservative elements, which suggests that REEs are immobile in the studied peat bogs and can be used as tracers of dust deposition. Plant macrofossils were also used to infer past environmental and humidity changes. The dust fluxes were reconstructed using the sum of REEs (ΣREE). The range of dust deposition varies from 0.2 to 3.8 g m−2 yr−1 in the Baie bog, while the IDH bog shows lower fluxes ranging between 0.1 and 1.2 g m−2 yr−1. The highest dust fluxes in the Baie bog were recorded from 1750–1000 cal. BP to 600–100 cal. BP and occur at the same time as periods of high variability in the macrofossil record (i.e. successive layers dominated by Sphagnum or Ericaceae). The timing of these events in the dust and macrofossil records also corresponds to documented cold periods. These two periods have been identified as episodes of climatic instability, which could have been caused by changes in the wind regime.

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Magnan, Gabriel, Michelle Garneau et Serge Payette. « Holocene development of maritime ombrotrophic peatlands of the St. Lawrence North Shore in eastern Canada ». Quaternary Research 82, n^o 1 (juillet 2014) : 96–106. http://dx.doi.org/10.1016/j.yqres.2014.04.016.

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AbstractMacrofossil analyses were used to reconstruct long-term vegetation successions within ombrotrophic peatlands (bogs) from the northern shorelines of the St. Lawrence Estuary (Baie-Comeau) and the Gulf of St. Lawrence (Havre-St-Pierre). Over the Holocene, the timing and the ecological context of peatland inception were similar in both regions and were mainly influenced by fluctuations in relative sea level. Peat accumulation started over deltaic sands after the withdrawal of the Goldthwait Sea from 7500 cal yr BP and above silt–clay deposits left by the Laurentian marine transgression after 4200 cal yr BP. In each region, the early vegetation communities were similar within these two edaphic contexts where poor fens with Cyperaceae and eastern larch (Larix laricina) established after land emergence. The rapid transitions to ombrotrophy in the peatlands of Baie-Comeau are associated with particularly high rates of peat accumulation during the early developmental stage. The results suggest that climate was more propitious to Sphagnum growth after land emergence in the Baie-Comeau area. Macrofossil data show that treeless Sphagnum-dominated bogs have persisted over millennia and that fires had few impacts on the vegetation dynamics. This study provides insight into peatland vegetation responses to climate in a poorly documented region of northeastern America.

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Roy, Gilles. « Une épidémie d’insectes, facteur de déboisement dans le Québec ». Cahiers de géographie du Québec 2, n^o 4 (12 avril 2005) : 233–40. http://dx.doi.org/10.7202/020090ar.

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Spruce budworm bas invaded the forest of Québec since 1939, especially the pines of the coniferous area. There are jour major infested regions : three are located on the North shore of the St. Lawrence river : in the Gatineau river bassin, in the Laurentians between the Lachute Area and lake St. John, and in the North Shore region behind Baie Comeau Sept-Iles. The fourth region starts behind Rimouski and spreads eastward, covering the whole Gaspé peninsula. In this last the authorities are quite concerned about this plague, which is becoming a serious menace to the forest industries. Various air-spays have been used during the past jour years in order to circumscribe the dammages, and more than 4,000,000 acres have been treated with DDT, first step toward the rehabilitation of the forest.

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Assani, Ali Arkamose, Ayoub Zeroual, Alexandre Roy et Christophe Kinnard. « Impacts of Agricultural Areas on Spatio-Temporal Variability of Daily Minimum Extreme Flows during the Transitional Seasons (Spring and Fall) in Southern Quebec ». Water 13, n^o 24 (7 décembre 2021) : 3487. http://dx.doi.org/10.3390/w13243487.

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Several statistical methods were used to analyze the spatio-temporal variability of daily minimum extreme flows (DMEF) in 17 watersheds—divided into three homogenous hydroclimatic regions of southern Quebec—during the transitional seasons (spring and fall), during the 1930–2019 period. Regarding spatial variability, there was a clear difference between the south and north shores of the St. Lawrence River, south of 47° N. DMEF were lower in the more agricultural watersheds on the south shore during transitional seasons compared to those on the north shore. A correlation analysis showed that this difference in flows was mainly due to more agricultural areas ((larger area (>20%) on the south than on the north shore (<5%)). An analysis of the long-term trend of these flows showed that the DMEF of south-shore rivers have increased significantly since the 1960s, during the fall (October to December), due to an increase in rainfall and a reduction in cultivated land, which increased the infiltration in the region. Although there was little difference between the two shores in the spring (April to June), we observed a decrease in minimum extreme flows in half (50%) of the south-shore rivers located north of 47° N.

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Burchsted, J. C. A., et Fred Burchsted. « Lady Crabs, Ovalipes ocellatus, in the Gulf of Maine ». Canadian Field-Naturalist 120, n^o 1 (1 janvier 2006) : 106. http://dx.doi.org/10.22621/cfn.v120i1.254.

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The Lady Crab (Ovalipes ocellatus), mainly found south of Cape Cod and in the southern Gulf of St. Lawrence, is reported from an ocean beach on the north shore of Massachusetts Bay (42°28'60"N, 70°46'20"W) in the Gulf of Maine. All previously known Gulf of Maine populations north of Cape Cod Bay are estuarine and thought to be relicts of a continuous range during the Hypsithermal. The population reported here is likely a recent local habitat expansion.

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Hein, Frances J., James P. M. Syvitski, Lynda A. Dredge et Bernard F. Long. « Quaternary sedimentation and marine placers along the North Shore, Gulf of St. Lawrence ». Canadian Journal of Earth Sciences 30, n^o 3 (1 mars 1993) : 553–74. http://dx.doi.org/10.1139/e93-043.

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Offshore areas, along the North Shore of the St. Lawrence Estuary, have major lithostratigraphic and seismostratigraphic units that relate to the advance or retreat of the Late Wisconsinan Ice Sheet, subsequent marine transgression or regression, and reworking of postglacial deposits. Glacial diamicton and glaciomarine units (acoustic units 1 and 2) were emplaced between >18 and 14.5 ka, by basal meltout or ice-marginal sedimentation; they reflect ice-proximal sedimentation associated with ice-terminal stillstands. Deep-water muds (acoustic unit 3) represent ice-distal accumulation of glaciomarine sediment from glaciofluvial plumes between 13.5 and 11 ka. After this time exceptionally thick nearshore coarse-grained deltaic and estuarine successions (acoustic unit 4) were deposited. The uppermost postglacial sediment (acoustic unit 5) forms the seabed and reflects a reworking phase concomitant with a lowering sea level and ablating Late Wisconsinan ice sheets.Glacioisostatic rebound, which occurred about 23 ka to the present, uplifted glacial and marine deposits and resulted in extensive reworking and production of modern placers. Heavy-mineral concentrations vary as follows: terrestrial tills, 9–20%; modem storm-berm and delta top deposits, 43–60%; delta slope deposits, 25–55%; and deep (170+ m) offshore sediments, 0–2%. Three stages occurred in marine placer formation: (1) 6700 BP, fluvial discharge was high, and fluvial-dominated deltas were built; marine limit was 30 m asl, with progradation of deltas and delivery of sediments with at most 2% heavy minerals; (2) 5200 BP, fluvial discharge was reduced; marine limit was 15 m asl, deltaic sediments were reworked, increasing heavy mineral concentration to 2–8%; (3) 2800 BP, fluvial input was greatly reduced, waves and tides were more influential, a strong littoral current system developed, causing significant reworking of nearshore sediments, heavy mineral concentrations increased, with values exceeding 20% locally. Mass budget calculations show that the second-cycle reworked sediment (acoustic unit 5) is a potential economic target (1 km3, or 1700 Mt). If 7% (using atomic weights) of this target sediment is ilmenite (FeTiO3). then 27 Mt of titanium may be available.

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Mellina, Eric, et Joseph B. Rasmussen. « Patterns in the Distribution and Abundance of Zebra Mussel (Dreissena polymorpha) in Rivers and Lakes in Relation to Substrate and Other Physicochemical Factors ». Canadian Journal of Fisheries and Aquatic Sciences 51, n^o 5 (1 mai 1994) : 1024–36. http://dx.doi.org/10.1139/f94-102.

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Using SCUBA and an in situ method of quantifying substrate characteristics, we describe patterns of zebra mussel (Dreissena polymorpha) distribution along the St. Lawrence and Hudson rivers and in Oneida Lake, New York, and develop empirical models for their abundance. Calcium-poor waters originating from rivers draining the Canadian Shield resulted in a complete lack of zebra mussel colonization along the north shore of the St. Lawrence River east of Montreal despite an abundance of suitable substrate. Calcium concentrations of 15 mg/L or less limited the distribution of zebra mussel. The entire south shore from Cornwall, Ontario, to île d'Orléans, Quebec, was colonized by zebra mussel wherever suitable substrate was found. Among the three systems, substrate size explained between 38 and 91% of the variability in density. Other factors such as Secchi depth, calcium concentration in the water, the presence of crayfish, native unionid abundance, and the maximum width of the river at the site increased the amount of explained variance across the different systems. A model based on substrate size also successfully explained patterns of zebra mussel abundance from published sources.

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Dionne, Jean-Claude. « A boulder-strewn tidal flat, north shore of the Gulf of St. Lawrence, Québec ». Géographie physique et Quaternaire 35, n^o 2 (1 février 2011) : 261–67. http://dx.doi.org/10.7202/1000443ar.

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A clay flat strewn with ice-drifted boulders occurs in a sheltered embayment near Harrington Harbour, North Shore of the Gulf of St. Lawrence. The embayment, approx. 7 km2 in area with a slope gradient less than 0.2°, is under the influence of tides ranging from 1.4 to 2.2 m and of a low wave energy regime. Ice entirely covers the flat during 3 to 4 months per year but may be present up to 5 months. Ice rafting, ice pushing, and ice gauging are moderately important processes in the embayment.

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Laforest, Sonia, Vincent Martin et Michel Boulé. « QUEBEC REGION'S SHORELINE SEGMENTATION IN THE ST. LAWRENCE RIVER : RESPONSE TOOL FOR OIL SPILL ». International Oil Spill Conference Proceedings 2005, n^o 1 (1 mai 2005) : 317–20. http://dx.doi.org/10.7901/2169-3358-2005-1-317.

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ABSTRACT The Quebec Region's shoreline description of the St. Lawrence River began in 1985 with the first shoreline interpretation by Environment Canada. This description was available as a paper version and was no longer adequate for oil spill response. An update was required in order to split the shoreline into segments and to digitize the information. A partnership was developed between Environment Canada, Eastern Canada Response Corporation and the Canadian Coast Guard to conduct the aerial survey and to do the segmentation. The cartography of segmentation covers the fluvial part of the St. Lawrence River (Montreal Region) up to the Gulf (including the Lower-North Shore and the St. Lawrence Islands). The database, developed specifically for that project, is oil spill-oriented. It includes geomorphologic information, from the supratidal to the lower intertidal zone, some statistical information and other requirements for the cleanup operation. For this operational database, useful for the response operation, links were developed with other databases and specialized oil spill software. The first system is GENIE Web, which is a Georeference Environmental Network for Information Exchange on the Web. The second system, ShoreAssess©, is a managing tool for SCAT teams in the field. Finally, a partnership with the Geography Department at the Université du Québec in Rimouski (UQAR) will help us to keep the St. Lawrence River coastal evolution up to date.

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Habbane, M. « Quaternary sedimentation and marine placers along the North Shore, Gulf of St. Lawrence : Discussion ». Canadian Journal of Earth Sciences 31, n^o 1 (1 janvier 1994) : 222–23. http://dx.doi.org/10.1139/e94-020.

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Hein, Frances J., et Bernard F. Long. « Quaternary sedimentation and marine placers along the North Shore, Gulf of St. Lawrence : Reply ». Canadian Journal of Earth Sciences 31, n^o 1 (1 janvier 1994) : 223–25. http://dx.doi.org/10.1139/e94-021.

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Turmel, Dominique, Jacques Locat, Jonathan Leblanc et Geneviève Cauchon-Voyer. « Tsunami modelling of the 7250 cal years BP Betsiamites submarine landslide ». Geological Society, London, Special Publications 477, n^o 1 (6 mars 2018) : 293–301. http://dx.doi.org/10.1144/sp477.9.

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AbstractOn the north shore of the St Lawrence Estuary (Québec, Canada), near the Betsiamites river delta, a large sub-aerial submarine landslide complex was mapped using multi-beam bathymetry and light detection and ranging (LiDAR) data. Previous analysis of this landslide complex revealed that, since 7250 cal years BP, at least four different landsliding events occurred to form the present morphology, in which over 2 km3 of material have been mobilized. The 7.25 cal ka BP landslide is of particular interest here: this landslide is entirely submarine and mobilized about 1.3 km3 of material, deposited over an area of 54 km2, which make this landslide the largest identified on the St Lawrence estuary seafloor. This landslide showed a runout distance of about 15 km. Landslide-generated tsunamis may be triggered by such a landslide, where a large volume of material is mobilized in a short time. Kinematic analysis of this landslide was previously performed, and here we use these analyses in order to perform tsunami wave generation and propagation modelling. It is shown in this analysis that, even if the mobilized volume is very high and there is a long runout, the tsunami generated is small with tsunami wave amplitudes of <1.5 m, except in the vicinity of the landslide. The highest tide elevation in this part of the St Lawrence Estuary is about 5.5 m, so the impact of such a tsunami wave may be limited.

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Assani, Ali A., David Landais, Mhamed Mesfioui et Martin Matteau. « Relationship between the Atlantic Multidecadal Oscillation index and variability of mean annual flows for catchments in the St. Lawrence watershed (Quebec, Canada) during the past century ». Hydrology Research 41, n^o 2 (1 février 2010) : 115–25. http://dx.doi.org/10.2166/nh.2010.055.

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This paper, based on an analysis of the mean annual flow (MAF) of 16 natural rivers over the period 1934–2000, has the following goals: (1) to determine the different temporal variability modes of the MAF in the St. Lawrence watershed, (2) to describe the temporal variability of the streamflow in each mode and (3) to analyze the influence of the AMO (Atlantic Multidecadal Oscillation) on the interannual and interdecadal variability of mean annual flows in this Quebec watershed. This paper shows that the interannual variability of mean annual flow was not synchronous on both sides of the river. During the period analyzed, MAF variability was characterized by a tendency to decrease on the south shore (right bank) but to increase on the north shore (left bank). A correlation analysis reveals that the influence of the AMO was limited exclusively to the north shore of the river, which is characterized by a continental climate. This correlation is negative. On the south shore, streamflow is correlated negatively to the AO (Arctic Oscillation).

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Dionne, Jean-Claude. « La mer de Goldthwait au Québec ». Les mers post-glaciaires : paléogéographie, paléoécologie et chronologie 31, n^o 1-2 (9 décembre 2010) : 61–80. http://dx.doi.org/10.7202/1000055ar.

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The Goldthwait Sea is defined as the late- and post-Glacial marine invasion in the St. Lawrence Estuary and Gulf east of Québec City. In Québec, this sea has submerged an area of about 25 000 km2. The largest areas submerged are the north shore of the St. Lawrence between Les Escoumins and Blanc-Sablon, the south shore between Levis and Tourelles, and the Anticosti Island. The upper limit of the Goldthwait Sea varies from place to place. The Goldthwait Sea began 14 000 years ago and land emergence is still in progress, since the pre-Wisconsin marine level has not been recovered yet. For a better chronology, this long interval needs to be subdivided. Three main periods have been recognized: Goldthwaitian I, II and III. However, a geographical subdivision is also needed. Numerous shorelines were observed at various elevations throughout the area formely submerged by the Goldthwait Sea. However, only a few shorelines are well developed and extensive, and correlations between former shorelines are difficult to establish. Only three levels are widespead and common to the Estuary and parts of the Gulf. The isostatic recovery has been rapid during the first three thousand years after déglaciation of the area: about 75%.

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Tessier, Nathalie, Sébastien Rioux Paquette et François-Joseph Lapointe. « Conservation genetics of the wood turtle (Glyptemys insculpta) in Quebec, Canada ». Canadian Journal of Zoology 83, n^o 6 (1 juin 2005) : 765–72. http://dx.doi.org/10.1139/z05-065.

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Throughout its range, the long-term persistence of the wood turtle (Glyptemys insculpta Le Conte, 1830) is jeopardized by habitat perturbations and commercial collection. The main objective of this study was to acquire knowledge on the genetic structure of wood turtle populations within Quebec, where the species reaches the northernmost limit of its range, to identify proper conservation units. The six known populations in Quebec were genetically characterized using five microsatellite loci. Genetic analyses revealed high variability among all populations (HO ranging from 0.561 to 0.886), suggesting that past population declines have not yet affected their genetic diversity. Since populations are located on both shores of the St. Lawrence River, two colonization hypotheses were tested to determine whether the River acted as a dispersal route or as a barrier. Results of AMOVA tests, phylogenetic analyses, and assignment tests demonstrated the clear distinction between populations from both shores, and three genetically different units were identified: the two populations on the north shore and a single homogenous group on the south shore.

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Rose, G. A., et W. C. Leggett. « Atmosphere–Ocean Coupling in the Northern Gulf of St. Lawrence : Frequency-Dependent Wind-Forced Variations in Nearshore Sea Temperatures and Currents ». Canadian Journal of Fisheries and Aquatic Sciences 45, n^o 7 (1 juillet 1988) : 1222–33. http://dx.doi.org/10.1139/f88-144.

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We found nearshore sea temperatures and currents on the north shore of the Gulf of St. Lawrence to be linked to wind-forced upwellings and downwellings. Multiple coherence of alongshore and cross-shore wind stresses with sea temperature (f > 1/d removed) was significant at periods > 3 d (maximum K2 = 0.90) and at 1.8 d. Partial coherences were frequency dependent. At periods > 3 d, which contained most of the variance alongshore forces dominated. Cross-shore winds were significant only at 1.8 d. A time domain model using lagged wind stress and cumulative air temperature as predictors explained 95% of the variance in post-stratification nearshore temperature. Temperature changes were virtually synchronous along 150 km of coastline. Alongshore currents were coherent with alongshore winds at periods > 2 d. Cross-shore currents were coherent with cross-shore winds at periods of 1–2 d. These results are compared with Csanady's models of wind-forced coastal thermocline oscillation. We conclude that alongshore winds force major upwellings and downwellings in this region. Cross-shore forces are important at f > 0.5/d. These dynamics regulate local primary biological processes and the transport of energy through their influence on fish migration.

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Rail, Jean-François, et Richard Cotter. « Sixteenth Census of Seabird Populations in the Sanctuaries of the North Shore of the Gulf of St. Lawrence, 2005 ». Canadian Field-Naturalist 121, n^o 3 (1 juillet 2007) : 287. http://dx.doi.org/10.22621/cfn.v121i3.476.

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The Migratory Bird Sanctuaries of the North Shore of the Gulf of St. Lawrence are important breeding grounds for many seabird species. The quinquennial censuses of seabirds in these sanctuaries have been carried out for 80 years (since 1925), in order to detect changes in the distribution and population levels of seabirds breeding on the North Shore. Between 1998-1999 and 2005, the most striking trends observed were the near doubling in numbers of Common Eiders in most sanctuaries, and the strong population growth rate of Razorbill. Unexplainable declines of Common Murre and Atlantic Puffin were observed at some of the larger colonies of these species. The last active colonies of Leach’s Storm-Petrel (Corossol Island) and Caspian Tern (Île à la Brume) on the North Shore seem on the verge of disappearing, with zero and three birds observed in 2005, respectively. Seabird populations in the larger, more accessible and disturbed sanctuaries are still markedly smaller than in historical times.Les refuges d’oiseaux migrateurs de la Côte-Nord du Golfe du Saint-Laurent constituent d’importants sites de nidification pour plusieurs espèces d’oiseaux marins. Des inventaires quinquennaux des oiseaux marins dans ces refuges sont effectués depuis 80 ans (depuis 1925), pour détecter les changements dans la répartition et les niveaux de population des oiseaux marins nichant sur la Côte-Nord. Entre 1998-99 et 2005, les tendances les plus marquantes étaient chez l’Eider à duvet, dont les effectifs ont pratiquement doublé dans la plupart des refuges, et chez le Petit Pingouin, dont les populations ont également connu une croissance rapide. Des déclins énigmatiques chez le Guillemot marmette et le Macareux moine ont été observés à plusieurs des colonies les plus importantes de ces espèces. Les dernières colonies actives d’Océanite cul-blanc (à l’île du Corossol) et de Sterne caspienne (à l’île à la Brume) sur la Côte-Nord semblent sur le point de disparaître, avec respectivement zéro et trois oiseaux observés en 2005. Les populations d’oiseaux marins demeurent à des niveaux bien endeça de ceux rapportés historiquement dans les refuges de grande superficie, davantage accessibles et sujets au dérangement.

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Guse, Nils, Nele Markones, François Bolduc et Stefan Garthe. « Distribution of seabirds in the Lower Estuary and Gulf of St Lawrence (Canada) during summer ». Seabird Journal, n^o 26 (2013) : 42–70. http://dx.doi.org/10.61350/sbj.26.42.

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We investigated the abundance and distribution patterns of a range of seabird species in the Lower Estuary and Gulf of St Lawrence in the western North Atlantic Ocean using ship-based surveys during the summers of 2007, 2008 and 2009. This area is known to be of particular importance for several seabird and cetacean species. We analysed distribution and abundance of common seabird species in mid and late summer, and estimated total numbers for the Southern Gulf, which was most intensively surveyed. Northern Gannets Morus bassanus were overall most abundant and widespread. Our at-sea estimate of 150,000 birds for the Southern Gulf constitutes 64% of the North American breeding population, rendering the site one of the most important areas for this species worldwide during this period. Our at-sea estimates suggest that according to the 1% threshold of the Ramsar Convention considerable proportions of the Canadian breeding population of Razorbills Alca torda (5-11%), Common Guillemots Uria aalge (2-3%), Black-legged Kittiwakes Rissa tridactyla (2-4%) and Black Guillemots Cepphus grylle (1-2%) use the Southern Gulf. Relative to their biogeographic populations, at-sea totals were also considerable in American Herring Gulls Larus smithsonianus (3-4%), Great Black-backed Gulls L. marinus (1-4%) and Great Northern Divers Gavia immer (1-4%). Areas of high seabird densities and multispecies aggregations (hotspots) occurred around the Gaspé Peninsula (Northern Gannets, alcids, Black-legged Kittiwakes, Larus gulls), in the Northwestern Gulf, along the Lower North Shore (near St Mary's Islands), along the west coast of Newfoundland (Bay of Islands to St Georges Bay), in Cabot Strait, around Cape Breton Island and the Magdalen Islands, as well as west and east of Prince Edward Island.

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Ryan, John J., Eric Dewailly, Andy Gilman, Claire Laliberté, Pierre Ayotte et Jean Rodrigue. « Dioxin-Like Compounds in Fishing People from the Lower North Shore of the St. Lawrence River, Québec, Canada ». Archives of Environmental Health : An International Journal 52, n^o 4 (juillet 1997) : 309–16. http://dx.doi.org/10.1080/00039899709602204.

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Edds, Peggy L., et J. Andrew F. Macfarlane. « Occurrence and general behavior of balaenopterid cetaceans summering in the St. Lawrence Estuary, Canada ». Canadian Journal of Zoology 65, n^o 6 (1 juin 1987) : 1363–76. http://dx.doi.org/10.1139/z87-216.

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Baleen whale movements were monitored from a hillside on the north shore of the St. Lawrence Estuary from 28 June to 27 September 1979. No diurnal or tidal relationships were apparent for the two most abundant species, the minke and finback. Single minke whales were seen almost daily. Adult pairs were only seen on four dates, and no adult-calf pairs were observed. Twenty-two small minkes were observed; three were possibly 1st-year calves. Finbacks occurred singly and in groups, particularly later in the field season. Resightings of distinctive finbacks indicate that adult pairings are temporary. One finback had been seen in the area in 1973–1975. Adult–calf pairs and seven single juveniles were also seen. Observations of finbacks pursued by whale watchers provide evidence that some regulation of the rapidly growing whale-watching industry may be warranted. Blue whales and humpback whales were seen far less frequently than minkes and finbacks. The relative abundances of minke, finback, and humpback were similar to 1973–1974 in the same area: however, blue whales were seen far more frequently in the past.

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Assani, Ali Arkamose. « Variability of Mean Annual Flows in Southern Quebec (Canada) ». Water 14, n^o 9 (23 avril 2022) : 1370. http://dx.doi.org/10.3390/w14091370.

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Snow is the main source of streamflow in temperate regions characterized by very cold and snowy winters. Due to global warming, these regions are experiencing a significant decrease in snowfall. The main objective of this study is to analyze the impacts of snowfall on the spatio-temporal variability of mean annual flows (MAFs) of 17 rivers, grouped into three hydroclimatic regions, from 1930 to 2019 in southern Quebec. In terms of spatial variability, snowfall is the variable most correlated with MAFs (positive correlation), followed by drainage density (positive correlation) and wetland surface areas (negative correlation). Due to the influence of these three factors, MAF values are generally higher in the most agricultural watersheds of the southeastern hydroclimatic region on the south shore than in the less agricultural watersheds of the southwestern hydroclimatic region on the north shore of the St. Lawrence River. As for temporal variability, the four statistical tests applied to the hydrological series detect no significant downward trend in MAFs, despite having reduced snowfall. Instead, they suggest an evolution toward an increase in mean annual flows, as a result of increased rainfall due to the increase in temperature. This evolution is more pronounced on the north shore than on the south shore, likely due to the presence of wetlands and others water bodies, whose runoff water storage capacity does not change over time to be able to store the surplus of the quantity of water brought by the increase in rain.

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Bourgeois-Roy, Andréanne, Hugo Crites, Pascal Bernatchez, Denis Lacelle et André Martel. « Abrupt mortality of marine invertebrates at the Younger Dryas-Holocene transition in a shallow inlet of the Goldthwait Sea ». Holocene 28, n^o 12 (10 septembre 2018) : 1894–908. http://dx.doi.org/10.1177/0959683618798130.

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The late Pleistocene–early Holocene transition period was characterized by rapid environmental change. Here, we investigate the impact of these changes on the marine invertebrates living in a shallow inlet of the post-glacial Goldthwait Sea. The site is located near Baie-Comeau (QC, Canada), where a number of remarkably well-preserved shell deposits are found along the Rivière aux Anglais Valley on the north shore of the St. Lawrence maritime estuary. Seven phyla of marine invertebrates with a minimum of 25 species or taxa were inventoried in a shell deposit, dominated by a community of Hiatella arctica with Mytilus edulis and barnacles composing the subcommunity. The majority of taxa identified in the shell deposit are boreal and sub-Arctic species; however, temperate species that exist today in the St. Lawrence maritime estuary have not been found. Based on marine invertebrate diversity and δ18O(CaCO3) of Mytilus edulis, the water in the shallow inlet of the Goldthwait Sea must have been cold and saline. The range of AMS 14C ages from 15 Mytilus edulis, constrained to 10,900 and 10,690 cal. yr BP, and exceptional state of preservation of adult and juvenile molluscan specimens suggest the abrupt mortality of entire invertebrate communities due to changing hydrodynamic conditions that included the combined effect of freshwater discharge from the receding Laurentide Ice Sheet and rapid isostatic uplift.

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Rail, Jean-François, et Richard Cotter. « Seventeenth census of seabird populations in the sanctuaries of the North Shore of the Gulf of St. Lawrence, 2010 ». Canadian Field-Naturalist 129, n^o 2 (4 août 2015) : 152. http://dx.doi.org/10.22621/cfn.v129i2.1695.

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Seabirds in the 10 migratory bird sanctuaries of the North Shore of the Gulf of St. Lawrence, Quebec, Canada, which were created in 1925, have been censused regularly for the last 85 years. The sanctuaries support 16 seabird species, many of which are found in significant numbers. From 2005 to 2010, some notable population changes were observed: large increases in Common Murres (Uria aalge), Razorbills (Alca torda), and two species of cormorants and continuing declines in Black-legged Kittiwakes (Rissa tridactyla) and Atlantic Puffins (Fratercula arctica). The status of Leach’s Storm-Petrel (Oceanodroma leucorhoa) and Caspian Tern (Hydroprogne caspia) is extremely precarious because of their small breeding populations. Between 2005 and 2010, seabird numbers in the sanctuaries increased 19% overall and were stable in most sanctuaries (≤ 15% change); however, notable increases were observed at Îles Sainte-Marie (60%), Baie des Loups (47%), and Île à la Brume (44%). Nonetheless, considering historical records, increased surveillance and raising of awareness of seabird conservation in local communities near the sanctuaries of Île à la Brume, Baie des Loups, and Saint-Augustin would be most beneficial.

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Lachance, Marius, Denis Brouard et Gordon Walsh. « Airborne transport of sulphur : Impacts on chemical composition of rivers on north shore of the St. Lawrence River (Québec) ». Water, Air, and Soil Pollution 39, n^o 3-4 (juin 1988) : 311–22. http://dx.doi.org/10.1007/bf00279477.

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Gagnon, Fabien, Thierry Tremblay, Justine Rouette et Jacques-François Cartier. « Chemical risks associated with consumption of shellfish harvested on the north shore of the St. Lawrence River's lower estuary. » Environmental Health Perspectives 112, n^o 8 (juin 2004) : 883–88. http://dx.doi.org/10.1289/ehp.6847.

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Chapdelaine, Gilles. « Fourteenth census of seabird populations in the sanctuaries of the North Shore of the Gulf of St. Lawrence, 1993 ». Canadian field-naturalist 109, n^o 2 (1995) : 220–26. http://dx.doi.org/10.5962/p.357616.

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NOËL, S., B. ANGERS et F. J. LAPOINTE. « Peromyscus populations and their Cuterebra parasites display congruent phylogeographical structure ». Parasitology 131, n^o 2 (15 avril 2005) : 237–45. http://dx.doi.org/10.1017/s0031182005007584.

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The relationships between populations of the Deer Mouse (Peromyscus maniculatus) and the White-footed Mouse (P. leucopus) and their respective Cuterebra parasites were examined. Population genetic structure of hosts and parasites was inferred using cytochrome oxidase mitochondrial sequences of specimens from 7 populations. Genetic analyses revealed that isolation-by-distance applies for P. maniculatus and its associated parasite (C. grisea). A significant correlation was also observed between the genetic distances of these host and parasite species. Furthermore, populations of P. maniculatus and C. grisea from the North and South shores of the St Lawrence River were found to be significantly different. This structure may be explained by the St Lawrence River being a dispersal barrier for both species. A robust analysis of the other species pair (P. leucopus and C. fontinella) could not be performed because of limited sample sizes.

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Kingsley, MCS, et R. R. Reeves. « Aerial surveys of cetaceans in the Gulf of St. Lawrence in 1995 and 1996 ». Canadian Journal of Zoology 76, n^o 8 (1 août 1998) : 1529–50. http://dx.doi.org/10.1139/z98-054.

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Aerial line-transect surveys of cetaceans were flown in the Gulf of St. Lawrence in late August and early September of 1995 and in late July and early August of 1996. Systematic north-south transects were spaced 15prime of longitude apart. In 1995, the study area comprised the entire Gulf, divided into three strata for analysis; 69% was flown. In 1996, a single stratum covered only the north shore shelf; 75% of the design was flown. The survey platform was a light high-winged aircraft with bubble windows flown at 213 m (700 ft). Ten species were seen. Minke whales (Balaenoptera acutorostrata), Atlantic white-sided dolphins (Lagenorhynchus acutus), and harbour porpoises (Phocoena phocoena) yielded enough sightings to support good estimates, while fin whales (Balaenoptera physalus), humpback whales (Megaptera novaeangliae), white-beaked dolphins (Lagenorhynchus albirostris), and long-finned pilot whales (Globicephala melas) yielded few sightings and unreliable estimates. Blue whales (Balaenoptera musculus) and belugas (Delphinapterus leucas) were seen too rarely to support any analysis. The tenth species was a small delphinid, not positively identified. Minke whales were ubiquitous, but more common in the northern strata. We estimated about 1000 in the whole Gulf in 1995 and about 600 in the northernmost stratum in 1996 (these numbers, and those following, are uncorrected for visibility bias). We estimated about 12 000 Atlantic white-sided dolphins in the Gulf in 1995, but in 1996 saw hardly any, perhaps because we flew the survey earlier. Harbour porpoises (12 000 in 1995 and 21 000 in 1996) were most numerous in the northern stratum, but were also widely distributed at lower densities in the central and southern Gulf. White-beaked dolphins (2500 in 1995 and 2500 in 1996) occurred only in the Strait of Belle Isle and the extreme northeastern Gulf. We estimated a few hundred fin whales in the northern and central strata and about 100 humpbacks, mostly in the northeast. Long-finned pilot whales were only seen in the southeastern Gulf, surveyed only in 1995 (about 1500).

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Ardisson, P. L., E. Bourget et P. Legendre. « Multivariate Approach to Study Species Assemblages at Large Spatiotemporal Scales : The Community Structure of the Epibenthic Fauna of the Estuary and Gulf of St. Lawrence ». Canadian Journal of Fisheries and Aquatic Sciences 47, n^o 7 (1 juillet 1990) : 1364–77. http://dx.doi.org/10.1139/f90-156.

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We investigated hierarchical organization and spatiotemporal discontinuities in species abundances in the epibenthic community of the Estuary and Gulf of St. Lawrence. Quantitative samples were obtained from 1975 to 1984, on 161 collectors (navigation buoys) moored yearly from May through November. Maximum biomass values of the dominant species, common to all regions studied, were used to assess epibenthic community structure. Numerical methods were used to characterize spatial structure and temporal variability of the dominant assemblage. Spatially constrained clustering and ordination techniques revealed six broad biogeographic zones whose limits vary yearly. However, spatially unconstrained clustering and ordination techniques showed two major sets of non-continguous localities, each characterized by a singular biotic structure. Further, spatial autocorrelation analyses showed a significant relationship between biomass and geographic distance. The resulting spatial structure of biomass was dependent on the species considered. The multidimensional Mantel technique showed an 8-yr period of variation in community structure at large (whole system, Gulf) and intermediate (North Shore plus Lower North Shore) spatial scales. The amplitude and asymmetry of this temporal cycle increased as the spatial scale decreased. In spite of the observed discontinuous spatial patterns, the temporal oscillations in community structure detected at different spatial scales suggest that the Estuary-Gulf system responds to the external input of auxiliary energy as an integrated system.

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Rail, Jean-François, et Gilles Chapdelaine. « Fifteenth Census of Seabird Populations in the Sanctuaries of the North Shore of the Gulf of St. Lawrence, 1998-1999 ». Canadian Field-Naturalist 118, n^o 2 (1 avril 2004) : 256. http://dx.doi.org/10.22621/cfn.v118i2.924.

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For the first time since the tradition began in 1925, the quinquennial census of seabirds in the Migratory Bird Sanctuaries of the North Shore of the Gulf of St. Lawrence was divided between two years in 1998-1999. Trends between 1993 and 1998-1999 were variable across species and sanctuaries. In particular, following the large decreases in both species noted in 1993, the 1998-1999 survey showed that Black-legged Kittiwakes had declined further, while the number of Herring Gulls had stabilized. Alcids were all doing well except for the Atlantic Puffin which showed severe yet unexplained drops at all major colonies. Law enforcement efforts appear reflected in seabird population trends, as well-patrolled sanctuaries such as St. Mary's Islands seem to do well, whereas many species at the Baie des Loups and Île à la Brume sanctuaries are far from their historical levels. In addition to a better law enforcement program, research is needed in order to identify other conservation problems that some species may be facing.Pour la première fois depuis 1925, l'inventaire quinquennal des oiseaux marins des refuges d'oiseaux migrateurs de la Côte-Nord du Golfe Saint-Laurent fut mené sur deux ans, soit en 1998 et 1999. Les tendances des populations entre 1993 et 1998-1999 étaient variables selon l'espèce et le refuge. En particulier, suite à une décroissance notée chez les deux espèces en 1993, l'inventaire de 1998-1999 a démontré que la Mouette tridactyle avait encore diminué, tandis que le nombre de Goélands argentés s'était stabilisé. Les populations d'Alcidés ont toutes semblé en bonne santé sauf celle du Macareux moine dont les colonies importantes ont diminué de façon sévère et inexpliquée. Les efforts de protection par l'application de la loi se reflètent visiblement dans les tendances des populations d'oiseaux de mer, puisque les refuges les mieux surveillés comme celui des Îles Sainte-Marie vont bien, alors que plusieurs espèces aux refuges de Baie des Loups et de l'île à la Brume sont loin de leurs niveaux historiques. En plus d'un meilleur programme d'application de la loi, la recherche est nécessaire pour identifier les autres problèmes de conservation auxquels certaines espèces font face.

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Lajeunesse, P., P. Dietrich et J. F. Ghienne. « Late Wisconsinan grounding zones of the Laurentide Ice Sheet margin off the Québec North Shore (NW Gulf of St Lawrence) ». Geological Society, London, Special Publications 475, n^o 1 (25 juin 2018) : 241–59. http://dx.doi.org/10.1144/sp475.10.

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Chapdelaine, Gilles, et Pierre Brousseau. « Thirteenth census of seabird populations in the sanctuaries of the North Shore of the Gulf of St. Lawrence, 1982-1988 ». Canadian field-naturalist 105, n^o 1 (1991) : 60–66. http://dx.doi.org/10.5962/p.357947.

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Brunton, Daniel F. « Great Plains Ladies’-tresses (Spiranthes magnicamporum) in the lower Great Lakes region and a new record for New York State ». Canadian Field-Naturalist 129, n^o 2 (5 août 2015) : 183. http://dx.doi.org/10.22621/cfn.v129i2.1700.

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Six populations of Great Plains Ladies’-tresses (Spiranthes magnicamporum Sheviak) have recently been discovered in three locations east of the lower Great Lakes region of Canada and the United States. The possible occurrence of S. cernua × magnicamporum hybrids was detected at one New York site. These discoveries are from both natural alvar and disturbed meadow and shore sites. The new records suggest that S. magnicamporum occurs more widely than was suspected previously, its presence perhaps masked by its similarity to the common S. cernua (L.) Richard. Eastern occurrences may represent a combination of post-glacial relict populations, responses to climate change, and the results of long-distance dispersal events. These range extensions constitute the most easterly known populations of S. magnicamporum in North America. They also represent new records for New York State (including Jefferson and St. Lawrence Counties) and for the City of Ottawa in Ontario.

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Clugston, David A., Jerry R. Longcore, Daniel G. McAuley et Pierre Dupuis. « Habitat use and movements of postfledging American black ducks (Anas rubripes) in the St. Lawrence estuary, Quebec ». Canadian Journal of Zoology 72, n^o 12 (1 décembre 1994) : 2100–2104. http://dx.doi.org/10.1139/z94-281.

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We used radiotelemetry to determine habitat use and movements of 38 female juvenile American black ducks (Anas rubripes) on the north shore of the St. Lawrence estuary, Quebec, from 28 August to 15 November 1991. Ducks separated into three groups based on habitat use: inland, estuarine, and those using a mixture of habitats. Ducks using mixed habitats used the greatest variety of habitat types, flew the greatest distances and most often between night roosts and day foraging areas, and were unlikely to be shot. The mean distance flown between night-use and day-use areas for all ducks increased nearly 50% after the hunting season began (overall mean = 6104 m, range 1500 – 26 384 m). Mean home range size was 27.6 ± 6.5 (SE) km2. Ducks exhibited stronger fidelity to wetlands used at night than to those used during the day. Ducks that were shot spent a high percentage of their time on the estuary (90.1 ± 7.4%) and exhibited high fidelity to a day-use area before the hunting season (73 ± 7.3%).

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Prinsenberg, S. J., A. Van Der Baaren et I. K. Peterson. « Ice ridging and ice drift in Southern Gulf of St Lawrence, Canada, during winter Storms ». Annals of Glaciology 44 (2006) : 411–17. http://dx.doi.org/10.3189/172756406781811439.

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AbstractDuring February and March 2004, Satellite-tracked ice beacons and helicopter-borne Sensors collected ice-drift and ice-thickness data from the Southern Gulf of St Lawrence, Canada, to Study the region’s ice-thickness evolution and ice-drift behavior in response to winter Storms. Three northeasterly Storms passed through the area during the observation period, pushing the pack ice against the north Shore of Prince Edward Island. The resulting Severe ice deformation caused major changes in the ice-thickness distribution of two pack-ice areas tracked by ice beacons that Survived the Storms. The ice drift ranged from 1.4% to 2.9% of the wind Speed during free ice-drift conditions, decreasing to 0% when the pack ice compacted against the Shoreline. Most of the thinner ice deformed first, increasing the mean ice thickness over 6–8 km line Sections around the beacons from 0.6 and 0.3 m before the Storms to 1.9 and 2.0 m after the Storms. The ice-thickness increases can be accounted for by the reduced pack-ice area due to ice ridging. Over the next 4weeks, deformation continued and the mean ice thickness around the beacons increased to 2.8 m, well in excess of the maximum undeformed possible ice growth of 65 cm. Ice charts captured the ice thickness of undeformed and composite ice floes but did not capture the ice volume in ice-rubble fields.

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Labbé-Morissette, Guillaume, Théau Leclercq, Patrick Charron-Morneau, Dominic Gonthier, Dany Doiron, Mohamed-Ali Chouaer et Dominic Ndeh Munang. « Classification of Coastal Benthic Substrates Using Supervised and Unsupervised Machine Learning Models on North Shore of the St. Lawrence Maritime Estuary (Canada) ». Geomatics 4, n^o 3 (30 juin 2024) : 237–52. http://dx.doi.org/10.3390/geomatics4030013.

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Classification of benthic substrates is a core necessity in many scientific fields like biology, ecology, or geology, with applications branching out to a variety of industries, from fisheries to oil and gas. In the first part, a comparative analysis of supervised learning algorithms has been conducted using geomorphometric features to generate benthic substrate maps of the coastal regions of the North Shore of Quebec in order to establish a quantitative assessment of performance to serve as a benchmark. In the second part, a new method using Gaussian mixture models is showcased on the same dataset. Finally, a side-by-side comparison of both methods is featured to provide a qualitative assessment of the new algorithm’s ability to match human intuition.

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Brêthes, Jean-Claude F., Gaston Desrosiers et Gilles Fortin Jr. « Croissance et production du bivalve Mesodesma arctatum (Conrad) sur la côte nord du golfe du Saint-Laurent ». Canadian Journal of Zoology 64, n^o 9 (1 septembre 1986) : 1914–19. http://dx.doi.org/10.1139/z86-287.

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Samples of Mesodesma arctatum (Pelecypoda) were collected during the summer of 1983 in the subtidal zone of the Saint-Jean River delta, on the north shore of the Gulf of St. Lawrence. Age was estimated by counting successive growth lines. Maximum longevity was estimated to be about 24 years. The von Bertalanffy growth equation was Lt = 48.1 (1−e−0,23(t−0,53)) mm. The instantaneous mortality rate was 0.26, estimated from a log regression of abundance versus age. The theoretical evolution of a single cohort was calculated; according to the model, biomass, expressed in dry weight, reached its maximum at 6 years and the ratio of somatic production to biomass was estimated to be 0.27. The age at first reproduction is between 3 and 4 years. The reproductive period seems to be during July. The reproductive effort was calculated from the weight difference between the reproductive and postreproductive periods and was determined to be 47% of the total production of the cohort.

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Rup, Michael P., Sarah A. Bailey, Chris J. Wiley, Mark S. Minton, A. Whitman Miller, Gregory M. Ruiz et Hugh J. MacIsaac. « Domestic ballast operations on the Great Lakes : potential importance of Lakers as a vector for introduction and spread of nonindigenous species ». Canadian Journal of Fisheries and Aquatic Sciences 67, n^o 2 (février 2010) : 256–68. http://dx.doi.org/10.1139/f09-180.

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Ballast water is recognized globally as a major vector of aquatic nonindigenous species (NIS) introductions; domestic ballast water transfers, however, have generally been considered low risk in North America. We characterize ballast operations of domestic ships in the Great Lakes – St. Lawrence River system (Lakers) during 2005–2007 to examine the risk of primary and secondary introductions associated with ballast water transfers over short distances. Results indicate that Lakers transported at least 68 million tonnes of ballast water annually. Approximately 71% of ballast water transfers were interregional, with net movement being from lower to upper lakes. A small proportion of ballast water discharged in the Great Lakes (<1%) originated from ports in the St. Lawrence River that may serve as sources for new NIS. These results indicate that domestic ballast water transfers may contribute to NIS introductions and are likely the most important ballast-mediated pathway of secondary spread within the Great Lakes. Future efforts to reduce invasion impacts should consider both primary and secondary introduction mechanisms.

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Brêthes, J. C., R. Saint-Pierre et G. Desrosiers. « Growth and Sexual Maturation of the American Sand Lance (Ammodytes americanus Dekay) off the North Shore of the Gulf of St. Lawrence ». Journal of Northwest Atlantic Fishery Science 12 (1 janvier 1992) : 41–48. http://dx.doi.org/10.2960/j.v12.a5.

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