(steelhead) are originally from the west coast.
•Rainbow trout first stocked in Lake Huron in 1876 in Michigan waters.
•First seen in Ontario waters in 1903.
•Abundance increased after the demise of lake trout in 1940-50’s.
•Numbers increased further with lamprey treatment in 1960’s.
• Hurricane Haze
in 1956 opened many rivers for spawning.
•Dam removal and fishways increased numbers to peak in 1970’s and early 1980’s.
•Loss of habitat and access is a concern for natural reproduction
•Increasing abundance resulted in more angling.
•Sanctuaries, varying open seasons, bag limit changes, and stocking were all used to reduced the effects of
increasing angler pressure.
•In 1970 and 1980’s most of fishing pressure was from stream anglers.
•With the creation of a significant salmon fishery in
the mid to late 1980’s the boat fishery
• Rainbow were
caught from both targeted and incidental boat
• The bulk of the cold water streams
accessible to annadromous salmonids occur
in the Ontario waters of Lake Huron
• The bulk of natural reproduction therefore
occurs in Ontario waters.
• Stocking was relatively stable through the
• In the mid 1980s volunteer groups were
allowed to develop private hatcheries for
stocking in Ontario waters which increased
the levels of stocking
• Stocking levels have been relatively stable
in the 1990s
Ontario waters declining rainbow numbers were evident in late 1980’s early 1990s in southern Georgian Bay.
• Some indications of declines also occurred
on Manitoulin Island
• Six fishways on streams in Ontario waters
allow for monitoring rainbow trout
fluctuations in abundance occur between years
• Indications indicate that declines have
occurred in rainbow trout runs.
• This supports anecdotal reports from anglers
that populations were down.
• At the same time increased stocking levels
at some tributaries has resulted in
increased abundance of stocked fish in
•Although declines have occurred stocking may have helped to dampen the effects of declining populations it
masked the loss of natural reproduction.
Concurrent assessment of Main Basin
tributaries did not indicate any decline in
rainbow trout abundance.
however been some indications of increased numbers
of stocked rainbow trout in the Main Basin
• As more stocked
fish are marked (Michigan) the percentage
of clipped fish could be increasing.
• Although any
reduction in abundance of wild fish could be
masked by stocking levels, the harvest levels of fish in the Ontario waters of the Main Basin are lower than Georgian Bay.
• In looking at the data it was determined
that rainbow trout populations were
depressed due to a series of dry years in
the late 1980s early 1990s which resulted in poor year classes
• The increase in angling pressure prevented
rainbow numbers from rebounding once more
favourable weather conditions
• Climatic conditions depressed the
populations but angling pressure kept them
• Harvest is much
larger in Georgian Bay than in the Main Basin.
• Although low water flows affected both
areas, Georgian Bay had the addition of
high harvest levels to keep the depressed
• Initially many of the public looked on
stocking as the salvation of rainbow
• Eventually through education they came to
realize that stocking is only part of any
•Through public consultation and discussions between PAC members and OMNR staff the recommendations were revised in the spring of 1997.
• The changes were finally accepted and were
passed in December of 1998.
bag limit reduction was retained for Georgian Bay, the southern main basin and the watershed rivers in Divisions 3 and 4.
• Many river specific changes were included in
the package which created seasonal
sanctuaries and changes rainbow trout
• These changes were intended to either reduce
harvest or address areas identified with
• Reduced seasons, sanctuaries, salmon
• MDNR started
stocking mainly Little Manistee River strain
rainbow trout in 1993 (naturalized stock 130 years in Lake Michigan).
• They since moved
to cessation of stocking domestic strain
•The catch rates of rainbow trout in U.S. waters of Lake Huron jumped in 1995 due to this change in strain.
• Catch rates declined in 1998 but have
increased since and the 2000 catch rate was
above the long-term average.
• Due to little natural reproduction and the
resulting dependance on stocking,
reductions in rainbow trout were not
evident in Michigan waters of Lake Huron.
• No evidence of
declines in rainbow trout runs are evident in
Main Basin tributaries in Ontario waters.
Michigan planted fish are sustaining numbers which are therefore not dependent on natural reproduction.
• Recent marking of rainbow trout by Michigan will soon determine the level of natural reproduction that is occurring in Ontario rivers on the Main Basin.
Ontario waters, where naturally reproducing populations are desired and important, there is a need to continue monitoring the populations
• If the rainbow trout populations decline
further more stringent regulations will
need to be considered.
• The concern is that changes made by that
time could be too late to avert a
decline, making rehabilitation a much longer process.
• The future of the rainbow trout populations
• There is concern that the regulation changes
made will not go far enough.
• The current drought conditions and low water
levels will result in more poor year
classes in the future.
• Additional monitoring is required.