No. 21: LARVÆ OF THE HALIBUT (Hippoglossus hippoglossus L.) ON THE ATLANTIC COAST OF NOVA SCOTIA

AbstractUpwelling occurs on several coasts of the world, but it has mostly been studied on eastern ocean boundaries. We investigated upwelling on a western ocean boundary for which limited information exists. Using daily in-situ data on sea surface temperature (SST), we found a marked contrast in coastal cooling between July 2014 (pronounced) and July 2015 (weak) at two locations 110 km apart on the Atlantic coast of Nova Scotia, Canada. These findings are consistent with a marked interannual difference in wind-driven upwelling. On the one hand, southwesterlies (which cause upwelling on this coast) were more frequent in July 2014 than in July 2015. On the other hand, Bakun’s upwelling index (which is based on wind data and geographic information) indicated that coastal upwelling was more common and intense in July 2014 than in July 2015, while the reverse was true for downwelling. Interestingly, a strong El Niño event occurred in July 2015, while no El Niño (or La Niña) conditions happened in July 2014. In a recent book evaluating upwelling systems around the world, the system that is the focus of the present study was not included. Therefore, our findings should stimulate future research on upwelling on the Atlantic Canadian coast, in that way helping to further develop the knowledge base for western ocean boundaries.

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SEISMIC STUDIES ON THE EASTERN SEABOARD OF CANADA: THE ATLANTIC COAST OF NOVA SCOTIA

Canadian Journal of Earth Sciences ◽

10.1139/e64-002 ◽

1964 ◽

Vol 1 (1) ◽

pp. 10-22 ◽

Cited By ~ 24

Author(s):

D. L. Barrett ◽

M. Berry ◽

J. E. Blanchard ◽

M. J. Keen ◽

R. E. McAllister

Keyword(s):

Nova Scotia ◽

Upper Mantle ◽

Atlantic Coast ◽

Seismic Refraction ◽

Compressional Wave ◽

Crust And Upper Mantle ◽

Compressional Waves ◽

Wave Velocities ◽

Shear Wave Velocities ◽

Eastern Seaboard

The results of seismic refraction profiles on the Atlantic coast of Nova Scotia and on the continental shelf off Nova Scotia are presented. Compressional and shear waves have been observed in the crust and mantle and suggest that the thickness of the crust is about 34 km. The compressional wave velocities recorded in the main crust and upper mantle are 6.10 and 8.11 km s−1 respectively. No compressional waves with values of velocity between these values can be identified, and this suggests that any "intermediate" layer is thin or absent. The corresponding shear wave velocities are 3.68 and 4.53 km s−1. Values of Poisson's ratio in the crust and mantle are 0.22 and 0.28. Alternative models of the crust which, on the evidence of travel times, might fit the observed results are discussed.

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COD MOVEMENTS ON THE CANADIAN ATLANTIC COAST

Contributions to Canadian Biology and Fisheries ◽

10.1139/f33-031 ◽

1933 ◽

Vol 8 (1) ◽

pp. 433-458 ◽

Cited By ~ 6

Author(s):

R. A. McKENZIE

Keyword(s):

Nova Scotia ◽

Prince Edward Island ◽

Cold Water ◽

Atlantic Coast ◽

Summer Season ◽

Warm Water ◽

Early Winter ◽

Cape Breton ◽

Inshore Waters ◽

Glace Bay

From 1925 to 1933 inclusive, during the summer season, 8,774 cod were tagged at eight points along the coasts of Nova Scotia and Prince Edward Island and eight per cent were recaptured during the following years, none after the sixth.Cod performing a restricted migration (less than 40 kilometres) were found to be in the majority off Halifax from July to September and off Shelburne in June and August in certain areas.Near Seal island in June, off Shelburne in July and September, and off Glace Bay in July and August, the majority of the cod were found to show orderly extended migrations. In the first two instances this movement was shoreward in the summer and seaward to about 130 metres in the early winter. The Glace Bay cod moved from the offshore banks just west of the Laurentian channel to the Cape Breton vicinity in the summer, returning early in the winter.A small percentage of the various stocks of cod performed roving migrations.The complete forsaking of the Cape Breton district for the offshore banks in the winter is attributed to the unfavourable ice cold water, while south-westward of Canso the movement off shore is thought to be caused by the very warm water inshore in the autumn and continued through the influence of the cold inshore waters several months later.As they grow older, the Shelburne cod remain progressively a little farther off shore when they move to shoal water each summer.

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Biochemical Implications of Seasonal Trends in the Iodine Values and Free Fatty Acid Levels of Commercially Produced Atlantic Coast Herring Oils

Journal of the Fisheries Research Board of Canada ◽

10.1139/f70-189 ◽

1970 ◽

Vol 27 (10) ◽

pp. 1669-1683 ◽

Cited By ~ 19

Author(s):

R. G. Ackman ◽

C. A. Eaton

Keyword(s):

Fatty Acids ◽

Fatty Acid ◽

Nova Scotia ◽

Atlantic Coast ◽

Relative Proportion ◽

Short Term ◽

Iodine Values ◽

Seasonal Decline ◽

Fatty Acid Compositions

Annual surveys of commercial herring oils produced in summer and fall off southwestern Nova Scotia and in winter and spring off southwestern Newfoundland showed iodine values (IV) mostly within the range 135 to 105 in both locations for the years 1965–70. Two systematic trends in IV with season were detected. The first extended uniformly over the whole of each fishery season and was limited to no more than ± 5 IV units. It is believed to represent the influence of long-term average environmental conditions that may vary from year to year and that establish the basic fatty acid compositions of the fish entering the fishery. The second was observed as a seasonal decline, over 2–3 months, of 20 IV units in the Nova Scotia fishery, and of 10 IV units in the Newfoundland fishery. It is proposed that this short-term effect follows from an increase in the relative proportion of the low-density, long-chain, monoethylenic fatty acids characteristic of clupeid oils that could decrease residual fat density at a time of general fat depletion and corresponding density increase for the fish as a whole.Free fatty acids (FFA) in freshly produced oils were also examined. In both fisheries % FFA seldom exceeded 1 and under optimum conditions the % FFA were consistently about 0.2–0.3. Annual seasonal % FFA effects were apparently restricted to an increase in April in the Newfoundland fishery associated with high IV oils of a pink colour denoting heavy spring feeding.

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The distribution of dissolved aluminum in Atlantic salmon (Salmo salar) rivers of Atlantic Canada and its potential effect on aquatic populations

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2012-053 ◽

2012 ◽

Vol 69 (7) ◽

pp. 1174-1183 ◽

Cited By ~ 4

Author(s):

Ian F. Dennis ◽

Thomas A. Clair

Keyword(s):

Nova Scotia ◽

Atlantic Salmon ◽

Salmo Salar ◽

Atlantic Coast ◽

Data Interpretation ◽

Potential Effect ◽

Atlantic Canada ◽

Aquatic Life ◽

Atlantic Salmon Salmo Salar ◽

Advisory Commission

Studies from the 1980s concluded that aluminum (Al) was not a significant contributor to Atlantic salmon ( Salmo salar ) toxicity in Nova Scotia, located on Canada’s Atlantic coast, because of the presence of dissolved organic matter that rendered ionic Al (Ali) biologically inaccessible. Since this earlier work, new interpretations of Ali effects, as well as improved techniques for its measurement, have been developed. However, no new data interpretation has been done to see if the conclusions reached in earlier work for Atlantic Canada were still valid. We sampled 97 salmon rivers from the provinces of New Brunswick (NB), Nova Scotia (NS), and the island of Newfoundland (NF) to determine total and Ali concentrations to see if results exceeded newer toxicity standards established by the European Inland Fisheries Advisory Commission. We found that southwestern NS, the region with the greatest loss of salmon populations, has seven rivers where autumn Ali values exceed values identified as toxic to aquatic life. A further three rivers exceed guidelines in NF. Our work shows that the sources of toxicity for salmon and other aquatic species in acidified environments are more complex than previously thought.

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Productivity of riverine habitats may be changing for American eel

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2018-0188 ◽

2018 ◽

Vol 75 (11) ◽

pp. 1773-1777 ◽

Cited By ~ 2

Author(s):

Heather Dawn Bowlby

Keyword(s):

Nova Scotia ◽

Atlantic Coast ◽

American Eel ◽

Regional Productivity ◽

Glass Eel ◽

Watershed Characteristics ◽

High Productivity ◽

Enhanced Production ◽

Juvenile Abundance ◽

Riverine Habitats

The panmictic population of American eel (Anguilla rostrata) is at risk, making any region that supports enhanced production important from a recovery perspective. Strong glass eel runs to a small number of rivers along the Atlantic coast of Nova Scotia are thought to indicate high productivity, partially buffering declines occurring in other regions. However, contrary to glass eel indices of recruitment, an index representing older juveniles has strongly declined in riverine habitats throughout Nova Scotia from 1995 to 2005, with evidence of substantial differences in relative abundance among watersheds. This suggests that glass eel indices may not reflect trends of older juveniles and consequently that the contribution of Atlantic coast rivers to population persistence may be overstated. More recent monitoring from two rivers shows divergent trends in juvenile eel abundance, underscoring the importance of widespread surveys to assess changes in regional productivity. Further evaluation of the watershed characteristics associated with higher juvenile abundance would aid in understanding differences in productivity among watersheds and possibly in facilitating increased spawning escapement for American eel.

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A new sea-level curve from Nova Scotia: evidence for a rapid acceleration of sea-level rise in the late mid-Holocene

Canadian Journal of Earth Sciences ◽

10.1139/e95-160 ◽

1995 ◽

Vol 32 (12) ◽

pp. 2071-2080 ◽

Cited By ~ 25

Author(s):

D. B. Scott ◽

K. Brown ◽

E. S. Collins ◽

F. S. Medioli

Keyword(s):

South Carolina ◽

Nova Scotia ◽

Sea Level ◽

Late Holocene ◽

Atlantic Coast ◽

Level Curve ◽

Global Response ◽

Level Curves ◽

Ice Melt ◽

Vertical Extent

A new late Holocene sea-level curve is presented from the Atlantic coast of Nova Scotia. Contrary to earlier data from the same area, this curve starts at 4400 sidereal years before present (BP) and shows a rapid acceleration between 4400 and 3800 BP, which coincides with a similar acceleration already reported from the Northumberland Strait (Nova Scotia) and an oscillation observed in South Carolina. Comparing the two Nova Scotia curves suggests that the acceleration lasts just over 1000 years and has a vertical extent of 10 m. One puzzling fact is that the 10 m vertical extent in Nova Scotia is 8 m more than the same event measured in South Carolina and it cannot be accounted for simply by postglacial isostatic depression, since that occurs on a much longer time scale. A closer examination of most of the sea-level curves from northeastern North America reveals that either the record is missing from this interval or it is inconsistent. We suggest that this acceleration is part of a global response that coincides with the end of the mid-Holocene warming period, possibly indicating a lag response between warming and ice melt.

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Ecological determinants of intertidal recruitment and metacommunity structure on the Atlantic coast of Nova Scotia

10.7287/peerj.preprints.26945 ◽

2018 ◽

Author(s):

Ricardo A. Scrosati ◽

Julius A. Ellrich

Keyword(s):

Nova Scotia ◽

Atlantic Coast ◽

Seawater Temperature ◽

Rocky Intertidal ◽

Late Winter ◽

In Situ Data ◽

Sessile Invertebrates ◽

Filter Feeders ◽

Metacommunity Structure ◽

Rocky Habitats

Rocky-intertidal species are often distributed as metacommunities along marine shores, as rocky habitats are patchy. Nearshore pelagic conditions often explain variation among the local communities, but most studies have been done on eastern ocean boundary coasts. We investigated potential drivers of intertidal metacommunity structure on the Atlantic coast of Nova Scotia. We studied the high intertidal zone of nine wave-exposed bedrock locations spanning 425 km of coastline. At each location in the spring, we measured the recruitment of barnacles and mussels, the two predominant sessile invertebrates. Satellite data on coastal phytoplankton abundance and particulate organic carbon (food supply for intertidal filter-feeders) and in-situ data on coastal seawater temperature explained to varying degrees the geographic structure of recruitment. In turn, the summer abundance of both filter-feeders was positively related to their spring recruitment. Ultimately, predator (dogwhelk) abundance increased with the recruitment and abundance of barnacles and mussels (the main prey of dogwhelks), suggesting that bottom-up forcing influences metacommunity structure on this coast. Sea ice constituted an overlapping source of variation. Drift ice leaving the Gulf of St. Lawrence in late winter disturbed intertidal communities in the northern locations, limiting local biodiversity compared with central and southern locations.

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Ecological determinants of intertidal recruitment and metacommunity structure on the Atlantic coast of Nova Scotia

10.7287/peerj.preprints.26945v1 ◽

2018 ◽

Author(s):

Ricardo A. Scrosati ◽

Julius A. Ellrich

Keyword(s):

Nova Scotia ◽

Atlantic Coast ◽

Seawater Temperature ◽

Rocky Intertidal ◽

Late Winter ◽

In Situ Data ◽

Sessile Invertebrates ◽

Filter Feeders ◽

Metacommunity Structure ◽

Rocky Habitats

Rocky-intertidal species are often distributed as metacommunities along marine shores, as rocky habitats are patchy. Nearshore pelagic conditions often explain variation among the local communities, but most studies have been done on eastern ocean boundary coasts. We investigated potential drivers of intertidal metacommunity structure on the Atlantic coast of Nova Scotia. We studied the high intertidal zone of nine wave-exposed bedrock locations spanning 425 km of coastline. At each location in the spring, we measured the recruitment of barnacles and mussels, the two predominant sessile invertebrates. Satellite data on coastal phytoplankton abundance and particulate organic carbon (food supply for intertidal filter-feeders) and in-situ data on coastal seawater temperature explained to varying degrees the geographic structure of recruitment. In turn, the summer abundance of both filter-feeders was positively related to their spring recruitment. Ultimately, predator (dogwhelk) abundance increased with the recruitment and abundance of barnacles and mussels (the main prey of dogwhelks), suggesting that bottom-up forcing influences metacommunity structure on this coast. Sea ice constituted an overlapping source of variation. Drift ice leaving the Gulf of St. Lawrence in late winter disturbed intertidal communities in the northern locations, limiting local biodiversity compared with central and southern locations.

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Abdominal Width and Sexual Maturity of Female Lobsters on Canadian Atlantic Coast

Journal of the Fisheries Research Board of Canada ◽

10.1139/f42-034 ◽

1944 ◽

Vol 6c (3) ◽

pp. 281-290 ◽

Cited By ~ 9

Author(s):

Wilfred Templeman

Keyword(s):

Nova Scotia ◽

Sexual Maturity ◽

Abdominal Segment ◽

Atlantic Coast ◽

Relative Width ◽

Maritime Provinces ◽

Nova Scotian

The relative width of the second abdominal segment was used for comparing onset of sexual maturity of female lobsters in 18 different localities of the Maritime Provinces, after establishing a correlation between them. Judging by the abdominal width, the smallest lobsters to carry eggs range from 17.6 to 22.6 cm. long, and the sizes when approximately half the female lobsters are mature range from 23.5 to 29.2 cm. in the whole southern part of the gulf of St. Lawrence and along the outer Nova Scotian coast at least as far as Jeddore; in southern Nova Scotia and Grand Manan the corresponding ranges in size are higher, being 29 to 32 cm. and 36.7 to 40.4 cm. respectively. Graphs are given showing the relative abdominal width in 189 berried lobsters.

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