983 resultados para St. Lawrence Estuary


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Rainbow smelt (Osmerus mordax) are small anadromous fish that live in nearshore coastal waters during much of the year and migrate to tidal rivers to spawn during the spring. They are a key prey species in marine food webs, as they are consumed by larger organisms such as striped bass, bluefish, and seabirds. In addition, smelt are valued culturally and economically, as they support important recreational and commercial fisheries. The Atlantic Coast range of rainbow smelt has been contracting in recent decades. Historically, populations extended from the Delaware River to eastern Labrador and the Gulf of St. Lawrence (Buckley 1989). More recent observations indicate that rainbow smelt spawning populations have been extirpated south of Long Island Sound, and evidence of spawning activity is extremely limited between Long Island and Cape Cod, MA. In the Gulf of Maine region, spawning runs are still observed, but monitoring surveys as well as commercial and recreational catches indicate that these populations have also declined (e.g., Chase and Childs 2001). Many diverse factors could drive the recently noted declines in rainbow smelt populations, including spawning habitat conditions, fish health, marine environmental conditions, and fishing pressure. Few studies have assessed any of these potential threats or their joint implications. In 2004, the National Marine Fisheries Service (NMFS) listed rainbow smelt as a species of concern. Subsequently, the states of Maine, New Hampshire, and Massachusetts were awarded a grant through NMFS’s Proactive Conservation Program to gather new information on the status of rainbow smelt, identify factors that affect spawning populations, and develop a multi-state conservation program. This paper provides an overview of this collaborative project, highlighting key biological monitoring and threats assessment research that is being conducted throughout the Gulf of Maine. (PDF contains 4 pages)

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The natural diet of 506 American lobsters (Homarus americanus) ranging from instar V (4 mm cephalothorax length, CL) to the adult stage (112 mm CL) was determined by stomach content analysis for a site in the Magdalen Islands, Gulf of St. Lawrence, eastern Canada. Cluster and factor analyses determined four size groupings of lobsters based on their diet: <7.5 mm, 7.5 to <22.5 mm, 22.5 to <62.5 mm, and ≥62.5 mm CL. The ontogenetic shift in diet with increasing size of lobsters was especially apparent for the three dominant food items: the contribution of bivalves and animal tissue (flesh) to volume of stomach contents decreased from the smallest lobsters (28% and 39%, respectively) to the largest lobsters (2% and 11%, respectively), whereas the reverse trend was seen for rock crab Cancer irroratus (7% in smallest lobsters to 53% in largest lobsters). Large lobsters also ate larger rock crabs than did small lobsters.

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The results of Continuous Plankton Recorder sampling in the NW Atlantic between 1958 and 2006 are presented for 11 plankton taxa in eight shelf and deep ocean regions. For shelf regions, phytoplankton abundances increased in the early 1990s, mainly in winter, as the contribution of Arctic-derived freshwater to the Newfoundland (NLS) and Scotian shelves (SS) increased. Farther east, in the sub-polar gyre, phytoplankton levels increased with rising temperatures during the 1990s and 2000s. In both areas, the changes can be explained by increased stratification. The increased influx of arctic water to the NLS in the 1990s was also probably directly responsible for the increased abundances of two arctic Calanus species (C. glacialis and C. hyperboreus) and indirectly responsible for the decreased abundance of Calanus I–IV (mainly C. finmarchicus), perhaps via changes in food composition. On the SS the arctic Calanus species increased in abundance in the 2000s, likely as the result of increased transport from the Arctic via the Gulf of St Lawrence. In the deep ocean, plankton seasonal cycles changed little over the decades and increasing phytoplankton levels in the 2000s were accompanied by increases in zooplankton abundance, suggesting bottom-up control. In shelf regions, phytoplankton increases in the 1990s were in winter and Calanus I–IV appeared earlier in spring than in previous decades. Zooplankton levels generally did not change overall however, perhaps because the species examined were mainly inactive during winter.

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Glaciation over the Pleistocene induced dramatic range fluctuations for species across North America such that postglacial recolonization by southern refugial lineages has characterized the genetic structure of northern North American species. Based on the leading edge model of postglacial range expansion, dispersal and rapid population growth in these northern taxa is expected to produce vast areas of genetic homogeneity. Previous work on the widely distributed spring peeper (Pseudacris crucifer) revealed six distinct mitochondrial lineages that diverged between 3-11 mya, expanding and contracting with glacial cycles. Beginning 16,000 yBP, receding glaciers permitted Eastern lineage refugia residing in the southern Appalachians to migrate northward into the St. Lawrence Valley then westward through most of central Canada. Peripheral populations at the northwestern range limit of P. crucifer in central Manitoba are likely descended from this westward expanding Eastern lineage. According to the central-marginal hypothesis, founder effects from colonization as well as limited gene flow is expected to reveal genetic differentiation and lower genetic diversity in peripheral populations. The goal of my study is to further our understanding of peripheral range dynamics in peripheral Manitoba populations of P. crucifer by determining their genetic affinity and diversity relative to more central populations in Ontario and Minnesota. In this study I amplified and aligned cytochrome b sequences from sample sites across central Manitoba to reconstruct a Bayesian phylogeny for P. crucifer; additionally, microsatellite loci were genotyped to estimate genetic diversity. Results from this study affirmed Eastern lineage descent for peripheral Manitoba sites by aligning with Ontario. Initial colonization by the Interior lineage between glacial retreat and the appearance of arid vicariance events may explain the apparent introgression of non-Eastern lineages in Manitoba. However, genetic diversity measured in expected heterozygosity (H¬e) was not found to be significantly different in Manitoba genotypes. Greater isolation by distance and inbreeding relative to Ontario and Minnesota is likely the primary driver of genetic variation in these sites. Further sampling is necessary to generate a more complete genetic population structure for P. crucifer.

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De nouvelles recommandations dans la production de canneberges suggèrent l’utilisation de l’irrigation souterraine, une méthode susceptible d’augmenter l’accumulation de sels dans le sol. Par ailleurs, le prélèvement d’eaux souterraines saumâtres dans des nappes résiduelles de la mer Champlain sous les dépôts d’argile dans la vallée du St-Laurent ou résultant du rehaussement des niveaux marins dans les zones côtières dû aux changements climatiques pourrait affecter la productivité des canneberges cultivées dans l’Est du Canada. Puisque très peu de données concernant la tolérance de la canneberge à la salinité sont disponibles, cette étude a été menée afin de déterminer si ces nouvelles recommandations pourraient éventuellement affecter le rendement de la plante. Dans une serre, des plants de canneberge ont été soumis à huit traitements obtenus à partir de deux méthodes d’irrigation (aspersion et irrigation souterraine) et quatre niveaux de salinité créés par des quantités croissantes de K2SO4 (125, 2 500, 5 000 et 7 500 kg K2O ha-1). L’irrigation souterraine a entraîné des conditions édaphiques plus sèches. Cependant, aucune différence significative de la conductivité électrique de la solution du sol (CEss) n’a été observée entre les deux types d’irrigation. Pourtant, les taux de photosynthèse et la nouaison étaient significativement plus faibles chez les plantes sous traitement d’irrigation souterraine. Les paramètres de croissance ont diminué de façon linéaire avec l’augmentation de la salinité alors que les paramètres de rendement ont connu une diminution quadratique avec l’élévation de la CEss. Une CEss moyenne de 3,2 dS m-1 pendant la floraison a provoqué une chute de 22% du taux relatif de photosynthèse et une diminution de 56% du rendement par rapport au témoin. Le suivi de la conductivité électrique du sol lors de l’implantation d’une régie d’irrigation souterraine de déficit en production de canneberges serait donc recommandable afin d’éviter le stress salin.

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Sediment relationships observed during geological mapping in southeastern Ontario indicate a relatively simple deglaciation history for the area during late Wisconsin time. The ice from the north (part of the Lake Simcoe lobe) and the Lake Ontario ice lobe, which were coalesced during most of late Wisconsin time, initially separated along the crest of the Oak Ridges Moraine. Available data indicate that the Oak Ridges Moraine is composed primarily of sediments pre-late Wisconsin in age capped by late Wisconsin till and interlobate deposits. Retreat of the northern ice was relatively steady and resulted in the deposition of the Dummer Moraines, a facies of the drumlinized till to the south. Retreat of the Lake Ontario ice lobe into the Lake Ontario basin was interrupted by a re-advance which covered the southeastern half of the map area. The northern ice had already retreated from the area by this time. The Lake Ontario lobe was fed through the St. Lawrence Valley, indicating that the Ottawa Valley was ice filled at this time. High level glacial lakes fronted the ice during deglaciation. These waters quickly fell to low levels as the ice retreated from the St. Lawrence Valley, opening lower outlets.

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Reissue of original ed.: Boston : J.P. Jewett ; Cleveland : H.P.B. Jewett, 1857. Cf. TPL 3664.

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This archive contains materials relating to the Great Lakes Waterways Development Association. The collection contains correspondence, financial information, clippings, biographical materials, media releases, presentations and publications. The bulk of the materials are correspondence.

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Oliver Phelps, son of Noah and Sarah (Adams) Phelps, was born in 1779 in Connecticut. In 1800 he married Abigail St. John, daughter of Lt. Samuel St. John and his wife Lois Hamilton. They had 9 daughters and 7 sons. Oliver Phelps came to Canada as a contractor on the first Welland Canal. In addition, he became a land owner and mill owner in partnership with William Hamilton Merritt. Oliver Phelps died in 1851 in Cayuga, Ontario along the Grand River. Some correspondence originates from a place called “Deep Cut”, an earlier name for the village of Allanburg, Thorold Township, Welland County.

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Transcript (spelling and grammar retained): “Col Proctor Sir I hope your goodness will excuse the Liberty I have taken of Enclosing a Letter for my nephew Mr. Hailes to your care, and begging the favor of you to forward it to him, - not knowing myself at what Post he is – With Great Respect I am Sir Your Most Obed Serv David Todd”

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The Guernsey post office stamps consist of 2 exhibition series souvenir sheets commemorating Major-General Sir Issac Brock, 1769-1812. The stamp was issued in 1996 to celebrate Guernsey’s attendance at Canada’s international stamp exhibition CAPEX 96. The stamps issued by the United States postal service consist of 1 sheet of stamps commemorating the 50th anniversary of the Peace Bridge, 1927-1977. The stamps issued by Canada Post include 5 commemorative day-of-issue envelopes with stamps featuring William Hamilton Merritt and the Welland Canal. This stamp was issued in 1974 to celebrate the 150th anniversary of the canal. There is also a set of 4 inscription corner blocks of stamps. These items are contained in an envelope addressed to Mr. J.N. Jackson, St. Catharines, ON. There is also a separate sheet of the same stamp. Also issued by Canada Post are 2 full sheets of stamps, one commemorating the 50th anniversary of the Peace Bridge (1927-1977), and one commemorating 25 years of the St. Lawrence Seaway (1959-1984). Lastly, there are 2 full sheets of stamps commemorating the 100th anniversary of the Royal Henley Regatta, issued in 1982.

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Includes 41 copies of plans of Royal Navy ships, ranging in date from 1784 to 1816. Some of the ships included are the Bonne Citoyenne, Niagara, Epervier, Comet, Contest, Ferret, Childers, Anacreon, Florida, Hind, Hermes, Psyche, Princess Charlotte, Contest, Prince Regent, Caroline, Thetis, Statira, Forte, Pelican, Crescent, Euryalus, Chesapeake, Acasta, Banterer, Leda, Endymion, Amphion, President, Tonnant, Ramillies, Boyne, and St. Lawrence. Many of these ships were used by the British during the War of 1812. The original plans are at the National Maritime Museum in Greenwich, London. Also included is a copy of a handwritten chart with the number and size of the British and United States Squadrons on Lake Ontario, March 1814 (during the War of 1812). This includes the number and caliber of long guns and carronades, as well as the weight of metal, for different ships. British ships include the Prince Regent, Princess Charlotte, Wolfe, Royal George, Melville, Moira, Sir Sidney Smith, and Beresford. American ships include the [General] Pike, Madison, Oneida, Sylph, Gen’l Tompkins[?], Conquest, Fair American, Ontario, Pert, Asp, and Lady of the Lake. Also included is a copy of a map titled “Track of the Action”, tracking the movements of the HMS Java and the USS Constitution, dated December 29, 1812, and a copy of a map of Lake Champlain and Plattsburgh Bay showing the position of a vessel(s), undated.

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The recipient of the letters is John Henry Dunn who was born on St. Helena (a British territory island of volcanic origin located in the South Atlantic Ocean) in 1792 to John Charles Dunn and Elizabeth Bazette. He was married to Charlotte Roberts on May 4th, 1820 and they had 6 sons and 2 daughters. He came to Canada in 1820 in which year he became the Receiver General for Canada. He held this position until 1841.Charlotte died in 1835. In 1822 he was named to the Province’s Legislative Council. He was president of the Welland Canal Company from 1825-1833. In 1836 he was named to the executive council of Upper Canada but resigned 3 weeks later with fellow counselors when lieutenant governor Sir Francis Bond refused the advice of the council. Dunn was made the Receiver General for the newly formed Province of Canada in 1841, and was elected to represent Toronto in the legislative assembly that year. He married his second wife on March 9th, 1842. Her name was Sophie-Louise Juchereau Duchsnay. They had a son and a daughter. In 1843 he resigned, and was not re-elected in 1844. He returned to England with his family and died in London on April 21, 1854. Dunn was a supporter of the Welland Canal, St. Lawrence Canals and other public improvements. Between the passage of the Canada Trade Act and the Act of the Union he had tried to insure that projects received funding despite financial constraints. He claimed that he has saved Upper Canada from bankruptcy. His son, Alexander Roberts Dunn received the Victoria Cross for his role in the Charge of the Light Brigade at Balaclava. Dunn Street in Niagara Falls is named after John Henry Dunn. The town and township of Dunnville were also named for him. Sources: http://biographi.ca/009004-119.01-e.php?id_nbr=3889 http://www.niagarafrontier.com/cityfalls.html

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In the original set, there were 10 medals with inventory numbers 1740-1749. This included Tecumseh, Chief of the Shawnees and construction in 1812 of Fort Prescott in Upper Niagara. These are not included in this collection. The Franklin Mint purchased the Wellings Mint in 1973.