Aquatic Exotics In Wisconsin

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Aquatic Exotics In Wisconsin
A Presentation Developed by
Wisconsin Sea Grant Advisory Services October
2006
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Aquatic Exotics In Wisconsin

• Wisconsin has become host to several aquatic
  species that never existed here naturally
• Some Atlantic Ocean species came in through the
  Welland Canal
• Lampreys, 1930s
• Alewife, 1949
• White perch, 1989
• Three-spine stickleback 1991

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Aquatic Exotics In Wisconsin

• Some were intentionally introduced
• Chinook and Coho salmon 1963
• Rainbow trout 1963
• Brown trout 1960s
• Carp in 1880s

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Aquatic Exotics In Wisconsin

• Some escaped from lakes, ponds or as bait
• Smelt
• Goldfish
• Grass Carp
• Rusty Crayfish
• Purple Loosestrife

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Aquatic Exotics In Wisconsin

• Some recent invaders came in the ballast water of
  sea-going ships
• Ruffe in 1986
• Zebra Mussels in 1988
• Spiny water flea in 1990
• Round goby in 1995

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Aquatic Exotics In Wisconsin

• Invasive species traits
• High reproductive rate
• Mature quickly
• Eat various types of food
• Tolerate poor water quality
• Easily adapt to new habitats

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Aquatic Exotics In Wisconsin

• Native species traits
• Have narrow food preferences
• Require certain spawning habitat
• Intolerant of poor water quality

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Aquatic Exotics In Wisconsin

• A Quick look at six recent invaders
• Zebra mussels
• Round goby
• Ruffe
• Purple loosestrife
• Eurasian milfoil
• Spiny water fleas

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Zebra Mussel
Max. size 2
Introduced via ballast water from Europe
First found in Lake St. Claire (MI) in 1988
Eats plankton, filters up to 1 liter of water
per day
Produce 40,000 eggs/year
Densities up to 700,000 per sq. meter
43,000 on a piece of notebook paper
Spread easily via planktonic larvae and adults
stuck on weeds and boats
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Zebra Mussel Life Cycle
Planktonic up to 1 month
Settle and attach to substrate
Wisconsin Sea Grant Advisory Services
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Zebra Mussels Colonize Lots of Things
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Zebra mussels get moved to new lakes by water in
and weeds on boats.
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Zebra Mussels 2008
(26 counties, 101 lakes)
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Wisconsin Lakes With Zebra Mussels
82
Why the big jump in 2006?
Better monitoring and additional infestations
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Ruffe
3-4 Long
Max. 10
S. Zienert
First found in 1986 in Lake Superior
Introduced via ballast water from Southern Europe
Affects perch, whitefish and minnows
Eats fish eggs, bottom-dwelling insects and worms
Now Present in Lakes Superior, Huron and Michigan
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Round Goby
3-4 Long
Max. 10
Introduced via ballast water from Europe
Affects sculpins and other bottom-dwelling species
Eats fish eggs, bottom-dwelling insects and worms
Present in all the Great Lakes, Chicago River
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• Purple Loosestrife

4-Sided Stem
2 Million Seeds per Year
Displaces Native Vegetation
Destroys Habitat

• Controlled by

Physical Removal
Beetles
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Galerucella beetles biocontrol for purple
loosestrife
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Purple Loosestrife
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• Eurasian Watermilfoil

• - Displaces native vegetation- Clogs boating and
  swimming areas- Spread by boaters through
  fragmentation
• ControlNorthern milfoil beetleChemical

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Eurasian milfoil compared to Northern milfoil
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Eurasian Milfoil
Present in62 counties gt 475 waters
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Rusty Crayfish

• Native to southern U.S.
• Introduced with bait
• Aggressive
• Destroys vegetation as they feed
• Displaces native crayfish
• Present in many Wisconsin lakes
• Often spread as bait

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Rusty Crayfish
Documented
Suspected
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Spiny Water Flea - BC CP
Bythotrephes cederstroemi Cercopagis pengoi
5mm Long
Max. 1/3
Long spines make them hard for fish to eat
Foul fishing lines and nets (look fuzzy or gooey)
Introduced via ballast water from Europe
Present in all the Great Lakes and Gile Flowage
in WI
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Preventing The Spread
Drain bilge water
Dispose of live bait
Clean off weeds
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If You Catch An Aquatic Exotic
KEEP It
Put it in a plastic bag or foil
FREEZE It
Put it in a freezer or ice chest
REPORT It
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Aquatic Exotics In Wisconsin

• How Can You Help?
• Learn To Identify Them
• Report If You Catch One
• Know Their Effects on the Ecosystem
• Prevent Their Spread
• Teach Others

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For More Information

• Visit the Sea Grant Nonindigenous Species Sites
• www.sgnis.org
• www.seagrant.wisc.edu
• Or Call
• Wisconsin Sea Grant
• [phone]
• Wisconsin Department of Natural Resources
• [phone]