Migration and Straying:
Cutthroat Trout and Dolly Varden Migration from Auke Lake
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Jerry Taylor
Fishery Research Biologist
(907) 789-6040
Jerry.Taylor@noaa.gov
The Auke Lake system is an important overwintering and rearing site
for Dolly Varden and cutthroat trout. Some spawning and rearing occurs
in the lake system, but spawner numbers and annual production are not
known. Dolly Varden were first counted during downstream migration in
1970, and Dolly Varden and cutthroat have been counted annually since
1979.
Dolly Varden are an important component of the marine and freshwater sport
fishery. Downstream migrants were first counted at Auke Creek in 1970,
and some or all fish were marked or tagged in 1970, 1980, 1983, and 1990
to learn more about their distribution and growth. Tagging studies
showed there is considerable movement between stream and lake systems in
the local area. It is important to continue studies on Dolly Varden at
Auke Creek, in order to document changes in population numbers. Weir
counts of Dolly Varden at Auke Creek indicate the runs have been in a
decreasing mode since 1995. Click here for
weir counts of Dolly Varden and cutthroat.
(To view and print this document,
Adobe Acrobat Reader freeware must be installed.)
Little was known of the life history of cutthroat trout in Auke Lake
before the start of meaningful tagging programs in 1994 and lake
population estimates in 1998. It is now apparent that Auke Lake
cutthroat trout have the most complex life history of any fish in the
system. Recent studies at Auke Creek and Auke Lake have produced
world-class information on these fish. Cutthroat trout tagged when they
leave Auke Creek in the spring may return the same year, or enter a
different lake to overwinter. Some trout return to Auke Creek after
several years. Some returned to Auke Lake, then stayed in the lake for
several years. Because all cutthroat leaving Auke Creek are tagged, the
occurrence of unmarked fish in the upstream migration shows there is
movement between lakes in the local area. Continued work on cutthroat
trout at Auke Creek is important to understand the status of the local
populations. Anecdotal information suggests that, historically, the
number of cutthroat trout in the system was greater than it is now, and
recent weir counts indicate the run is in a decreasing mode.
For more information on cutthroat trout and Dolly Varden at Auke
Creek, contact
Judy_Lum@adfg.state.ak.us.
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