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Schneider, C.P., R.W. Owens, R.A. Bergstedt, and R. OGorman, 1996. Predation
by Sea Lamprey (Petromyzon marinus) on Lake Trout (Salvelinus namaycush) in
Southern Lake Ontario, 1982-1992, New York Department of Environmental Conservation
Reprinted from Canadian Journal of Fisheries and Aquatic Sciences(1996) 53:
1921-1932
Predation by Sea Lamprey (Petromyzon marinus) on Lake
Trout (Salvelinus namaycush) in Southern Lake Ontario, 1982-1992
Abstract:
Dead lake trout (Salvelinus namuycush) killed by sea lamprey (Petromyzon
marinus) were
collected from the bottom of Lake Ontario using bottom trawls. The number of dead lake
trout per hectare could be predicted from the number of type A-l sea lamprey marks
observed on live fish in September gillnet surveys (r 2 = 0.60, P < 0.01)
but not from the sum of marks of types A-l, A-2, and A-3 combined. Sea lamprey selectively
attacked and killed the largest lake trout. The lengths and ages of live fish with A-l
marks increased as the population of longer, older lake trout in the lake increased, and
the length distributions of fish killed by sea lamprey were not different (P > 0.05)
from those of live fish with A-l marks in 5 of 6 years where comparisons could be made.
Compared with Lake Superior strain lake trout, Seneca Lake strain fish were only 0.41
times as likely to be attacked by sea lamprey and were less likely to die from an attack
(both differences P < 0.05). Conservative estimates of the numbers of lake trout killed
by sea lamprey in southern Lake Ontario from October to mid-November ranged from 17 000 in
1988 to 121 000 in 1984.
Entire Paper:
Contact: C.P. Schneider, New York Department of
Environmental Conservation, Cape Vincent Fisheries Research Station, Cape Vincent, NY
13618
Keywords: Sea_lamprey, Ecological_interactions, Environmental_impacts
Product Type: Research,
Impact
User Type: Resource_management
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