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• I wanted to take the opportunity of this meeting to make everyone aware of the current state of lake trout rehabilitation in Lake Huron. • Contributions from Jim Johnson & Aaron Woldt MDNR,
•There are six sites of observed natural reproduction of lake trout in Lake Huron
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• The first and most successful is Parry Sound.
• Was once an historically significant lake trout fishery.
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•One of only two remnant stocks (Iroquois Bay being theother)
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• Parry Sound one of the largest and deepest Bays in Georgian Bay
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• No commercial fishing has been allowed in the bay
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• The bay was somewhat isolated which protected the fish from sea lamprey.
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•Parry Sound one of the largest and deepest Bays in GB
• 9207 ha, 112 m maximum depth, 41 m mean depth
• Shallow channel joining to GB (12 m)
• No commercial fishing
•The isolation of Parry Sound from Georgian Bay, combined with few local streams being suitable for sea lamprey reproduction, likely reduced the effect of sea lamprey predation on these lake trout and saved them from extirpation. •But by 1958 lamprey parasitism was 45 time higher than that observed in 1988 to 1998.
•Large lake trout are able to survive lamprey attacks better than small fish.
• The absence of a commercial fishery prevented the combined effects of sea lamprey parasitism on smaller lake trout and exploitation of larger/older fish which led to the extirpation of other stocks in the Great Lakes. • This lack of commercial fishing allowed the larger Parry Sound lake trout to survive until sea lamprey control was initiated in the early 1960s. • Residual sea lamprey and a continuing sport fishery appears to have prevented rehabilitation, however, and kept the population numbers depressed.
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•Wild eggs were first collected in 1979 from the few remaining fish • Wild progeny and backcross were both stocked starting in 1981, backcross was terminated in 1991 due to concerns with genetics and poor survival
• The planted trout attracted anglers by 1985
•  An outbreak of a disease in the Great Lakes (epizootic epitheliotrophic disease virus-EEDv) prevented wild egg collections and stocking of lake trout did not occur in 1989 to 1991. • Stocking in Parry Sound terminated in 1997due to sufficient natural reproduction and evidence that natural reproduction should be enhanced with a stocking cessation • MNR will continue to stock in Georgian Bay and Five Mile Bay with lake trout derived from the Parry Sound stock.
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•These are the current fishing regulation in Parry Sound
•The trend of management has been to lower bag limits (3 to 1), 
•The harvest season has been reduced to 8 weeks in winter, and 10 weeks in summer
•The area is closed to lake trout fishing - Oct., Nov. & Dec.
•The remainder of year is C&R seasons (21 weeks - winter, spring and fall)
• (5 weeks Jan, 12 weeks spring, 4 weeks fall)
•spawning fish are protected by a 61 cm max. size limit.
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• The number of fishing lines allowed in winter was reduced to one (to limit catch and release mortality).
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• The area protected by these regulations was further expanded into Georgian Bay in 1997.
• since 1988 progressive increase abundance of wild
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• Representative of all inner sites.
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•Low wild fish initially, major increases starting in 1995 and 1996.
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• Stocked abundance quite variable, recent decline is effects of no stocking in 1989 to 1991.
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•Slight decline in wild fish in 1999, suggest close watching.
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•in 1994 only 31% of 68 fish were wild, by 1999 84% of 214 fish were wild.
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• Lake trout numbers were always higher in refuge
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• Less dramatic increase in refuge
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• Supplemental stocking was therefore terminated in 1997.
•Although the role that hatchery fish played in the rehabilitation of Parry Sound is difficult to assess, some indication can be inferred from the timing of events.
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• The first fish stocked should have reached maturity by 1987. 
• And indeed by 1988 stocked fish accounted for 59% of spawners.
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• Stocked fish should therefore have contributed to the 1988 and 1989 year classes. • From this, an increase in progeny from these spawning events would be expected by 1995.
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• The proportion of unclipped/wild lake trout in the angler catch did increase significantly in 1995. • Wild lake trout we also being captured in areas of the bay where only clipped fish were caught in previous years. • This circumstantially indicated that stocked fish played an important role in the rehabilitation of Parry Sound lake trout.
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•additional protection for Parry Sound lake trout that migrate into GB
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•vulnerable to commercial and sport fisheries.
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•interim step - bag limit reduction to one
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•five year review of our Lake Trout Rehabilitation Plan and options for Parry Sound will be reviewed.
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•In summary what seemed to have worked for Parry Sound was:
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•Effective sea lamprey control
•Stocking of progeny from native stock
•Stocking at levels exceeding 4.5 yearlings/ha
•Significant angler exploitation control
•Cessation of stocking when sufficient natural reproduction occurs
•Protection of fish during all times of the year
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• Concerns with lake trout in southern Georgian Bay could be addressed by bag limit reduction
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• Starting to get pressure to liberalize regulations and fishery improves.
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• Cessation of stocking is the biggest change, need to proceed carefully.
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•Are stocking 5,000 lake trout into Five Mile Bay annually
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• The second remnant stock of lake trout is located in Iroquois Bay in northern Lake Huron
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• Iroquois is a deep isolated bay similar to Big Sound but much smaller.
• area = 496 ha    
•deep
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•Pre 1960's- popular recreational lake trout fishery
• Iroquois Bay broodstock used since 1995
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•Will be used for other locations in Lake Huron.
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•In South Bay - Iroquois Bay lake trout attain a larger size, mature later in life and survive longer than Lake Manitou and backcross lake trout
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• Seem distinctly different from other lake trout stocks in the Great Lakes
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• Mishubishi (inland lake strain)
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• mature lake trout captured during fall spawning shoal assessment netting, multi-gillnet spawning survey
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•few unclipped fish being seen
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•seeing fewer mature fish on spawning shoals
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•currently estimated there are 80 to 200 spawners
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• Worked with an advisory committee to come up with options
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• Regulations even more stringent than Big Sound. 
•Iroquois where the Big Sound was in the late 1960s
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• Will need much time to rehabilitate.
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•With factors of higher lamprey abundance and possible competition with chinook salmon could be further constraints. • need to develop assessment plan for monitoring the stock
• Third location of natural reproduction in Ontario waters.
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• Site where original population was completely gone.
• 8,600 ha basin,
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• another deep basin with a restricted opening to main lake
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• sheltered conditions make it attractive to anglers under most weather conditions
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• no special angling regulations for this location
• Have also planted Michipicoten, Slate Island, Iroquois Bay and Backcross strains
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•since 1995 all Lake Manitou strain
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•  Very high harvest from 1979-1983, very few survived past one year • Commercial exploitation controls in place from 1984 to 1992 •  Wild fish observed from 1986-1992 consisted of 321 fry and 67 age 0 to age 2 juveniles collected • 1990 revealed the first significant natural year class of lake trout since 1948
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•1988 some  brook trout genes
•1991 & 1992 no  brook trout genes
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• little monitoring from 1993 to 1998.
• In 1999 SLIN and fall trapnetting done by Wikwemikong First Nation •in 100 SLIN nets 15 lake trout were caught and only 2 were unclipped • in Sept. and Oct. of 1999 trapnets were set, captured 29 lake trout of which 28 were clipped.
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•South Bay both sport and gillnet fisheries
• Commercial exploitation controls in 1984 to 1992 helped rehabilitation •  As the population increased sport and commercial exploitation has increased. • High levels of exploitation observed in the early 1990s appear to have prevented full rehabilitation
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• The present level of reproduction insufficient to achieve rehabilitated population. •continue to annually stock 10,000 Lake Manitou strain lake trout
• Need additional harvest controls.
• In spring of 1981 fertilized lake trout eggs were found in the Rockport area near Alpena.
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•In 1983, five two year old unclipped lake trout were taken in same area.
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• Since 1984 young of the year lake trout have been regularly taken using a 30 foot bottom trawl at North Point, Thunder Bay This map shows the location of North Point •In addition, a few lake trout YOY were sampled in 1992, 1993 and 1994 of Mischley Reef in the centre of Thunder Bay • Significant numbers of unclipped spawners were sampled on Mischley Reef during the falls of 1991-93 and 1997-98.
• Few of the fish sampled were older than age seven.
• Many other reefs were investigated in area but only this one has any significant evidence of natural reproduction.
• In 1986,  42 YOY lake trout were sampled in the North Point area of Thunder Bay •From 1987 to 1990 there were consistent but lower numbers in trawls • Trawl catches declined in the early 1990s, recovered, then have declined again since 1995.
• Only two YOY were captured in 1999
• Much of the natural reproduction in U.S. waters of Lake Huron is centered in the Thunder Bay area. •Despite presence of more abundant lake trout in the south and more optimal spawning habitat in the north. •  It appears the main mortality to lake trout in the middle and north part of the Main Basin is from sea lamprey •Possibly with treatment of the St. Marys River survival of lake trout will increase and more natural reproduction can occur
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•  Six Fathom Bank was sampled from 1993 to 1998.
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• In all years except 1996 YOY lake trout were encountered.
•  Drop in spawning stock size may have contributed to the decline in catch. • Seneca strain lake trout were not available for several years, causing lapse in stocking of this strain. • Other strains stocked on Six Fathom have not contributed to the spawning population • Stocking of Seneca strain has resumed and it is expected the spawning population will increase over next five years • Seneca strain are better able to survive sea lamprey predation
• Site in Owen Sound
• Sampled by trapnet since 1994
•Initially no unclipped lake trout
• It was only in 1998 that significant numbers of unclipped lake trout were observed.
• The relative abundance of unclipped fish has remained stable from 1998 to 2000.
• High levels of commercial harvest has reduced planted fish abundance in recent years and likely has limited any accumulation of wild fish.
• First unclipped lake trout in 1998
• Increased to:
• 8% unclipped in 1998
• 12% in 1999
• 30% in 2000 
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• Aged lake trout from 2000 indicated that representation of wild fish is increasing • i.e. younger age classes higher proportion of unclipped fish.
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• Still very preliminary but encouraging
• Need to investigate further, look for spawning site(s) • Currently no evidence of wild fish in other nearby locations.
• First plan 1996
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• Included significant public consultation
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• Confirmed public’s desire to rehabilitate lake trout
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• Plan almost five years old now, and we know more about lake trout
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• Need to review and update the plan
•Had 16 rehabilitation sites
• Should we look at less sites?
• Difficult to assess all
• Different levels of assessment for different areas?
• high-Parry Sound, Iroquois Bay, Fitzwilliam Is.
• moderate-Owen Sound, South Bay
• lowest- other areas
• Considering options, will present options to public
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• Need  more protection provided from both commercial and sport fishing
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•  Currently  high and escalating commercial lake trout incidental catch,   trying to address this issue
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• More broad based sport fishing regulations (one fish, no harvest of unclipped fish?)
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• Rehabilitation is international goal
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• Need to coordinate efforts and regulations between Ont. and Mich.
• Tribal areas in the State of Michigan  waters of  Lakes Superior, Huron and Michigan have been co-managed by MDNR and COTFMA since the mid 1980s • This allowed Tribal commercial fisheries in the northern part of Lake Huron • The agreement was re-negotiated this year for 20 years. • The agreement spells out the allowable harvest of species, mainly whitefish, lake trout and chinook salmon.
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• Looked at different options to meet population size targets 
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• Example is northern LH, reduce commercial mortality by 60% and 24” minimum size limit for sport
• Many locations of Great Lakes excessive lake trout mortality by sea lamprey & exploitation has hindered or prevented rehabilitation. •All of success highlights the need for significant controls on exploitation to achieve rehabilitation • Low bag limits, maximum size limit, very short harvest seasons and refuge area were most effective management techniques used in Parry Sound to control angling mortality.
•May need to consider these in other areas
•OMNR is closely reviewing the commercial fish harvesting data to develop methods to reduce incidental harvest
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•Confounding factors such as Early Mortality Syndrome (associated with thiamin deficiency) may hinder lake trout rehabilitation in other locations.  •(Thiamine is above threshold levels for EMS in Parry Sound lake trout.) •And the ability to control mortality will give lake trout the best chance to increase natural reproduction and rehabilitate . • Even with severe angling restrictions in Parry Sound there are concerns, what about areas of lake with much less protection,  can we expect any rehabilitation success at all?
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