Lake Trout Ecosystems in a Changing Environment - Chapter 5 pot

... in 85 lake trout lakes. A large number (50 ) of these lakes had drawdowns occurring after lake trout spawning. Draw- downs occurred before lake spawning on 39 lakes and during spawning on 14 lakes ... spawning areas in the littoral zones of Lake aux Sables using a tarp (Benoît and Legault, 2002) led lake trout to abandon these areas and reproduce in the artificial d...

Ngày tải lên: 11/08/2014, 10:21

... fourfold increase in stream SO 4 2- , a decrease in ANC from positive to negative values, a decrease in stream pH to below 5. 0, and increases in stream Al, largely occurring as the toxic inorganic ... 1982). Although Al is abundant in nature, it is relatively insoluble in the neutral pH range and thus unavailable biologically. Acid- neutralizing capacity largely controls...

Ngày tải lên: 11/08/2014, 10:22

... 8,000 years ago. Lake Agassiz was impounded between the retreating ice margins and the Manitoba Escarpment — the present-day remnants including Lakes Manitoba, Winnipeg, Dauphin, and Winnipegosis. ... banksiana) and red pine (Pinus resinosa); poorly drained sites are characterized by black and white spruce, balsam fir, tamarack (Larix laracina), eastern red cedar (Juniperus virginiana),...

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... Superior basin, and finally eastward into Lake Barlow-Ojib - way (Mandrak and Crossman, 1992). Lake Barlow-Ojibway extended across northeastern Ontario and northwestern Quebec, and drained into the ... America, 18,000 5, 000 years ago Geological Survey of Canada, Map 170 3A. Evans, D.O. and Olver, C.H., 19 95, Introduction of lake trout (Salvelinus namaycush) to inland lakes o...

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... propose stocking all available hatchery-reared lake trout allocated to a lake in a given year into one selected locality that has an abundance of spawning habitat, leaving other areas of the lake unstocked. ... obstacles faced by lake trout in the Great Lakes. Approximately 330 million yearling and fingerling lake trout were released into the Great Lakes from 1 950 to...

Ngày tải lên: 11/08/2014, 10:21

... m as a result of a twofold increase in atmospheric CO 2 levels. Acidification of lakes by the input of mineral acids also results in increased transparency (Effler et al., 19 85) , again via removal ... 1-m increase in transparency would result in an increase in Z 10 of ca. 1 m. Following a 2-m increase in transparency, optimal habitat volumes in the same lakes would be...

Ngày tải lên: 11/08/2014, 10:21

... of lake surface areas for 1916 Ontario lake trout lakes and 6824 other lakes in Ontario. 40 30 20 10 0 All Lakes Lake Trout Lakes 0-2 5 5 0-7 5 10 0-1 25 15 0-1 75 20 0-2 25 25 0-2 75 30 0-3 25 35 0-3 75 40 0-4 25 45 0-4 75 > ;50 0 Lake ... (m) 0-1 0 1 0-2 0 2 0-3 0 3 0-4 0 4 0 -5 0 5 0-6 0 6 0-7 0 7 0-8 0 8 0-9 0 9 0-1...

Ngày tải lên: 11/08/2014, 10:22

... Molot, L .A. , 2003, Predicting optimal habitat boundaries for lake trout (Salvelinus namaycush Walbaum) in Canadian Shield lakes, Canadian Journal of Fisheries and Aquatic Sciences (in press). Dillon, ... long-term integrity of lake trout habitat will require the management of activities in the catchments of lakes that affect DOC inputs to lakes. Climate change and acid rain als...

Ngày tải lên: 11/08/2014, 10:22

... pollutants may be increasing Hg concentrations in lake trout in small Boreal lakes. Experimental lake acidification was observed to increase Hg in fish (Wiener et al., 1990) and Hg in fish in lakes ... lakes in south-central Ontario, Canada, Archives of Environmental Contamination and Toxicology 15: 50 5 51 2. Franzin, W.G., Barton, B .A. , Remnant, R .A. , Wain, D.B., and...

Ngày tải lên: 11/08/2014, 10:22

... open-water lake trout fisheries occurred on Algonquin Park lakes in the late 1940s and early 1 950 s. Martin (1 954 ) found that in lakes where lake trout mature at a young age (5 years) and a small ... it and applying it to their seasonal or annual quota. An individual tag-and-quota system for lake trout has been in effect since 1991 in Clearwater Bay and adjacent Ec...

Ngày tải lên: 11/08/2014, 10:22