scholarly journals Migration of Postsmolt Atlantic Salmon, Salmo salar, Off Northeastern Newfoundland, As Inferred by Tag Recoveries in a Seabird Colony

1988 ◽  
Vol 45 (3) ◽  
pp. 568-571 ◽  
Author(s):  
W. A. Montevecchi ◽  
D. K. Cairns ◽  
V. L. Birt

Northern gannets, Sula bassanus, and possibly other seabird species nesting on Funk Island off northeastern Newfoundland preyed on postsmolt Atlantic salmon, Salmo salar. Salmon comprised less than 1% of 2928 regurgitated food samples collected from gannets at the colony. Ten smolt tags were recovered in and near the gannetry during August or September in 1984 through 1986. The tags were from smolts released 3–4 mo earlier in the Penobscot River (Maine) (n = 7) and one each from the Saint John River (New Brunswick) and the Lower Clyde and LaHave rivers (Nova Scotia). These recoveries provide evidence that postsmolt Atlantic salmon from rivers in New England, the Bay of Fundy, and the Atlantic coast of Nova Scotia migrate off eastern Newfoundland This migratory pattern contrasts with that of postsmolts from the Gulf of St. Lawrence, which tend to move northwards along Newfoundland's west coast and through the Strait of Belle Isle.

2012 ◽  
Vol 69 (7) ◽  
pp. 1174-1183 ◽  
Author(s):  
Ian F. Dennis ◽  
Thomas A. Clair

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.


Author(s):  
Shelley K Denny ◽  
Lucia M Fanning

Issues related to fisheries governance are a source of debate and tension between the Indigenous Mi’kmaq people of Nova Scotia and the Canadian Department of Fisheries and Oceans (DFO) in matters concerning Atlantic salmon, Salmo salar. Within the context of the existing governance regime, this analysis compares the concept of salmon conservation and management from a Mi’kmaq perspective and proposes a collaborative co-existence approach for effective salmon governance in Nova Scotia. This approach begins by using co-management as a process, Two-Eyed Seeing as the design, and treaties as the model to achieve shared objectives of maintaining and improving abundances of salmon populations, in spite of differing mechanisms for addressing the interwoven complexities of multiple realities, conservation, and cultural identity.


1981 ◽  
Vol 38 (12) ◽  
pp. 1612-1625 ◽  
Author(s):  
Richard L. Saunders

This paper discusses the diversity of Atlantic salmon (Salmo salar) expressed as anatomical, physiological, and behavioral differences among stocks in the Atlantic Provinces of Canada and New England, USA. Evidence is reviewed for environmental and genetic influence on a number of stock-specific traits. Unique qualities of particular stocks are described. The loss of salmon from much of its former range is documented and discussed in relation to stock characteristics important in rehabilitation efforts. The mixed stock fisheries in Greenland and Newfoundland are considered from the point of view of interception. It is concluded that identification and management of specific stocks in the Greenland fishery are impracticable at present but that identification of North American components, using discriminant function analysis of scale growth patterns and smolt tagging, should be continued. In Newfoundland knowledge gained from tagging studies allows a significant degree of management of stocks from mainland Canada together with those from Newfoundland and Labrador. Since it is impracticable now to manage the fisheries off Greenland and Newfoundland and off the major Canadian Maritimes salmon-producing rivers—the Miramichi, Restigouche, and Saint John—in strict recognition of stocks, it is suggested that it may be possible to characterize an assemblage of like stocks from given areas and to identify and manage for these in large mixed-stock fisheries. Possible impacts of hatchery plantings are discussed in relation to prospects of success and effects on native stocks. It is concluded that we have the biological basis for evaluating likelihood of success and degree of danger to native stocks from extensive plantings of hatchery-reared juvenile salmon and that such evaluation should be conducted when embarking on projects involving use of hatchery-reared fish as part of a major salmon enhancement program in Atlantic Canada.Key words: genetics, environmental influence, rehabilitation, enhancement, interception, hatcheries, aquaculture


1989 ◽  
Vol 46 (11) ◽  
pp. 2003-2018 ◽  
Author(s):  
Gilles L. Lacroix

Densities, growth, and production of juvenile Atlantic salmon (Salmo salar) were estimated at sites in two acidic rivers of different pH, the Westfield and North rivers, in Nova Scotia, Canada, from 1982 to 1984. Annual production was significantly lower in the more acidic Westfield River (< 0.4 g∙m−2∙yr−1 at pH 4.7–5.4) than in the North River (1.4 g∙m−2∙yr−1 at pH 5.6–6.3). Low production rates in the more acidic river were attributable to the lower densities and poorer survival of juveniles at the lower pH levels. Low densities of parr in the more acidic river were a function of the high initial mortality of postemergent fry, and the mortality of parr during periods of pH minima such as over winter. Marking and recapture information and trapping at a weir for counting migrating fishes indicated that there was little emigration of parr other than in the spring when some movements occurred preceding and during smoltification. Average potential yield of 2-yr smolts was 0.8 smolt/100 m2 in the Westfield River and in the range of 2.7–6.6 smolts/100 m2 at higher pH levels in the North River. Growth was not limiting to production at the lower pH levels. After the first winter, 1-yr-old parr were much larger at the lower pH than they were at less acidic pH levels, the faster growth possibly resulting from the lower density of parr at the lowest pH. A temperature-related biphasic growth of 1-yr-old parr with periods of maximum growth in spring and autumn was recorded. Reduced production, a result of deleterious effects of low pH on survival and density in the Westfield River was probably sufficient to prevent the continued maintenance of a naturally produced salmon population in that river, whereas production at higher pH levels in the North River was comparable to that in near-neutral waters of other areas.


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