NON-NATIVE SALMOINDS IN LAKE SUPERIOR

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NON-NATIVE SALMOINDS IN LAKE SUPERIOR

• Don Schreiner, MNDNR
• Steve Schram, WIDNR
• Shawn Sitar, MIDNR
• Mike Petzold, OMNR

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History

• First successful introductions began in late
  1800s with rainbow and brown trout
• Coho and chinook salmon first introduced by MI in
  mid 1960s, quickly followed by other agencies
• Introductions targeted at controlling exotic
  invaders and redirecting angling effort
• All species have become naturalized and are
  sustained largely by natural reproduction

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Fish Community ObjectiveNon-native Salmonids

• Manage populations of Pacific salmon, rainbow
  trout and brown trout that are predominately
  self-sustaining, but that may be supplemented by
  stocking that is compatible with restoration and
  management goals established for native fish
  species.

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Role on Non-native Salmonids in the Lake Superior
Fish Community

• Species are migratory - spawn in streams and
  migrate to the lake after smolting
• Thermal habitat is limited
• Impact on a lake-wide basis is minimal
• May have significant impact in tributaries and
  near-shore areas

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Waters of Lake Superior
0-240 ft (0-80 meters)
gt 240 ft (gt 80 meters)
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(No Transcript)
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The Fishery

• Approximately 1/3 of total angler catch
• Expanded sport fishing opportunities
• Provided increased shore and stream opportunity
• Created a surface water trolling fishery
• Contaminant levels less than lake trout

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Status Open Water Creel Surveys

• Wisconsin 1972 2000, May 1 Sept. 30
• Minnesota 1972 2000, Memorial W.E. Sept. 30
• Michigan 1987 2000, Selected sites May 1
  Sept. 30
• Ontario Intermittent - selected sites - diaries
  
• Lack of standardization in other recreational
  fisheries
• Spring and fall stream fisheries
• Winter fishery

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Distribution of Major Salmonids in U.S. Waters of
Lake Superior from 1990-2000
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Distribution of Major Non-native Salmonids in
U.S. Waters of Lake Superior from 1990-2000
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Distribution of Major Salmonids in Ontario Waters
of Lake Superior 1987-1999
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Distribution of Major Non-native Salmonids in
Ontario Waters of Lake Superior 1987-1999
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Status

• Stocking history
• Catch history
• CPUE in open water recreational fishery

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Rainbow Trout

• Introduced in 1895
• Present population largely a result of natural
  reproduction
• Return rate of stocked yearlings less than 1
  except Kamloops
• Increased control of angler exploitation
• Abundance has declined since the 1950s lake
  trout, pacific salmon, increased exploitation,
  stream habitat

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Number of Rainbow Trout Stocked in Lake Superior
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Number of Rainbow Trout Caught in U.S. Waters of
Lake Superior
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CPUE of Rainbow Trout in Lake Superior
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Brown Trout

• Introduced in late 1890s
• Have naturalized in a number of tributaries
• WI and MI still stock in localized areas
• Hatchery contribution 50 in WI and 40 in MI
• Brule River supports largest naturalized run

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Number of Brown Trout Stocked in Lake Superior
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Number of Brown Trout Caught in U.S. Waters of
Lake Superior
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CPUE of Brown Trout in U.S. Waters of Lake
Superior
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Coho Salmon

• Introduced by MI in 1966, MN from 1969-1974
• Quickly became naturalized, no longer stocked
• Life cycle of 3 years, anglers mostly exploit age
  2
• Harvest fluctuates greatly fishing mostly one
  YC
• Slower growth and smaller size than other Great
  Lakes

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Number of Coho Salmon Stocked in Lake Superior
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Number of Coho Salmon Caught in U.S. Waters of
Lake Superior
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CPUE of Coho Salmon in Lake Superior
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Chinook Salmon

• Introduced by MI in 1967, followed by other
  agencies
• Use larger rivers for spawning
• BKD relatively low compared to other Great Lakes
• Approximately 75 of chinook salmon are produced
  by natural reproduction Peck et al 1999
• All agencies continue to stock effectiveness
  ?????

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Number of Chinook Salmon Stocked in Lake Superior
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Number of Chinook Salmon Caught in U.S. Waters of
Lake Superior
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CPUE of Chinook Salmon in Lake Superior
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Chinook Salmon Study

• Contribution of hatchery fish to fishery
• Agency specific fin clips 1988-1990
• Returns assessed from 1990-1994
• Wild fish comprised 75 lake-wide
• Hatchery contribution greatest MN-WI-MI-ON
• Significant movement

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Hatchery Contributions of Chinook Salmon
1990-1994
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Pink Salmon

• Accidentally introduced in 1956
• Have become naturalized
• Life cycle of 2 years initially, 3 year life
  cycle common
• Harvest fluctuates greatly one year class
• Late fall boat fishery and fall stream fishery

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Number of Pink Salmon Caught in U.S. Waters of
Lake Superior
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Mean Size of Non-native Salmonids in U.S. Waters
of Lake Superior
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Mean Size of Non-native Salmonids Among States of
U.S. Waters of Lake Superior
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Recommendations

• Meeting FCOs based on present knowledge
• Determine impact on native species in tributaries
  and near-shore areas
• Standardized creel surveys
• Critically review present stocking programs
• Use of Lake Superior strains
• Effectiveness CostBenefit
• Realistic expectations
• Disease